Heart Disease and Pregnancy [2nd ed.] 9781316156063

Table of contents :
Cover......Page 1
Half-title......Page 3
Title page......Page 5
Copyright information......Page 6
Table of contents......Page 7
List of contributors......Page 9
Preface......Page 11
Consensus statements......Page 12
Components of preconception counseling......Page 17
Informed choice and understanding......Page 18
Preparing for pregnancy......Page 19
Risk of congenital abnormality......Page 20
References......Page 21
Counseling patients on the risks of pregnancy......Page 22
Classification of cardiac conditions......Page 23
Efficacy of use of contraceptive agents......Page 24
Combined hormonal contraceptives......Page 27
Desogestrel......Page 28
Injectable progestogens (Nexplanon®—previously Implanon®)......Page 29
Barrier methods......Page 30
Pulmonary arterial hypertension......Page 31
References......Page 32
Clinical implications......Page 35
Clinical implications......Page 37
Cardiac anatomical change......Page 38
Cardiac functional change......Page 39
Clinical implications......Page 41
References......Page 42
Introduction......Page 45
Recognition of the cardiac condition......Page 46
Trivial and low-risk cardiac lesions......Page 47
What should the woman be told?......Page 48
The fetus and fetal surveillance......Page 49
References......Page 50
Introduction......Page 52
The spectrum of maternal heart disease......Page 53
Organization of antenatal care......Page 54
Recommendations for organization of antenatal care......Page 56
References......Page 58
Initial assessment of the patient......Page 59
Risk assessment......Page 60
Organizing care and monitoring......Page 61
Echocardiography......Page 63
Ventricular size and function......Page 64
Valvar abnormalities and function......Page 65
Electrocardiography......Page 66
References......Page 67
Potential adverse effects of drugs......Page 69
Thiazide diuretics......Page 70
Hydralazine......Page 71
Angiotensin II inhibitors......Page 72
Sotalol......Page 73
Beta-adrenergic receptor blockers......Page 74
Breastfeeding......Page 75
Oxytocin......Page 76
Ritodrine......Page 77
References......Page 78
Introduction......Page 81
Fetal and maternal risks of cardiopulmonary bypass......Page 82
Key points regarding cardiopulmonary bypass in pregnancy......Page 84
Radiation and contrast agent risks to fetus and mother......Page 85
Mitral valve stenosis......Page 87
Aortic valve stenosis......Page 89
Mitral or aortic regurgitation......Page 90
Dissection of the aorta......Page 91
Coronary interventions......Page 92
Congenital heart disease......Page 94
Miscellaneous interventions......Page 95
References......Page 96
The effect of prenatal diagnosis on outcome......Page 100
Level 2......Page 101
Previous affected child......Page 102
Metabolic risk factors......Page 103
Equipment required......Page 104
Counseling......Page 105
Ongoing assessment: Fetal well-being......Page 106
Fetal tachycardia......Page 107
Early detection of congenital heart disease......Page 108
References......Page 109
Maternal risk factors......Page 112
Maternal indices......Page 113
Cyanotic vs acyanotic heart disease......Page 114
Fetal surveillance......Page 115
Fetal assessment......Page 117
Women needing heart surgery in pregnancy......Page 118
References......Page 119
Tissue prostheses......Page 122
Unfractionated heparin......Page 123
Warfarin......Page 125
Low-molecular-weight heparin......Page 126
References......Page 128
Aortopathies and related conditions......Page 131
Nonaortopathy complications of Marfan syndrome......Page 132
Risk stratification......Page 133
Monitoring during pregnancy......Page 134
Delivery issues......Page 135
Hypertension......Page 136
Aneurysm formation......Page 137
Conclusions......Page 138
References......Page 139
Mitral and aortic stenosis......Page 141
Treatment......Page 142
Congenital mitral stenosis......Page 143
Prepregnancy assessment of isolated aortic stenosis......Page 144
Cardiopulmonary bypass surgery during pregnancy......Page 145
References......Page 146
Preconception evaluation and counseling......Page 147
Congenital right heart lesions......Page 148
Atrial septal defect......Page 149
Tetralogy of Fallot......Page 150
Pulmonary stenosis......Page 151
Congenitally corrected transposition of the great arteries......Page 152
Transposition of the great arteries......Page 153
Univentricular hearts after Fontan-type operations......Page 154
Summary......Page 156
References......Page 158
Definition of PH......Page 160
Pathophysiology of PH......Page 161
Making the diagnosis of PH......Page 162
The challenges of managing a pregnant patient with PH......Page 163
Management of PH in pregnancy in the pre-PAH treatment era......Page 164
Management of PH in pregnancy in the PAH treatment era......Page 166
Preconception counseling......Page 168
Monitoring the mother at delivery and in the early postpartum period......Page 171
Mode of delivery and anesthetic management......Page 172
References......Page 173
Introduction......Page 176
Pregnancy outcome......Page 177
Incidence......Page 178
Pathophysiology......Page 179
Clinical features......Page 180
Long-term management......Page 181
Mortality and prognosis......Page 182
Recurrence and risks in future pregnancies......Page 183
Hypertrophic cardiomyopathy......Page 185
References......Page 186
Introduction......Page 190
Treatment of acute coronary syndrome......Page 191
References......Page 193
Incidence of arrhythmias during pregnancy......Page 196
Mechanism of arrhythmia in women with heart disease during pregnancy......Page 197
Ventricular tachycardia......Page 198
Atrial flutter......Page 199
Electrophysiological study and catheter ablation......Page 200
Considerations with specific antiarrhythmic drugs......Page 201
Arrhythmia during pregnancy in specific categories of CHD......Page 202
Anesthetic management of women with arrhythmias during delivery......Page 203
References......Page 204
Epidemiology......Page 207
Predisposing factors......Page 208
Preventative measures......Page 209
Diagnosis......Page 212
References......Page 213
Epidemiology......Page 215
Hemodynamic changes during pregnancy......Page 216
Heart transplant physiology......Page 217
Rejection......Page 218
Death......Page 219
Surveillance during pregnancy......Page 220
References......Page 222
Significance of cardiac disease in the peripartum period......Page 224
Mode of delivery......Page 225
Third-stage management......Page 226
Regional anesthesia/analgesia......Page 227
Regional analgesia......Page 228
Disadvantages of general anesthesia......Page 229
Noninvasive cardiac output monitoring......Page 230
Equipment and environment......Page 231
References......Page 232
Hemodynamic changes......Page 234
Circulating volume changes......Page 235
Alteration in cardiac shunting of blood......Page 236
Timing of maternal deaths during the puerperium......Page 237
Valvular and aortic disease......Page 238
Multidisciplinary care during the puerperium......Page 239
Pain relief, oxygen, and posture......Page 240
References......Page 241
Introduction......Page 243
Pulmonary hypertension......Page 244
Tetralogy of Fallot......Page 245
Valvar heart disease......Page 246
Aortopathy......Page 247
References......Page 248
Introduction......Page 250
Peripartum cardiomyopathy......Page 251
Connective tissue disorders and aortopathies......Page 252
References......Page 253
Appendix A: New York Heart Association classification of cardiovascular disease......Page 256
Appendix B: Antenatal care pathway......Page 257
Index......Page 271
Colour Plates......Page 283

Citation preview

Heart Disease and Pregnancy

Heart Disease and Pregnancy Second Edition Edited by

Philip J. Steer, BSc MD FRCOG

Emeritus Professor, Imperial College London, Academic Department of Obstetrics and Gynaecology, Chelsea and Westminster Hospital, London, UK

Michael A. Gatzoulis, MD PhD FACC FESC

Professor of Cardiology, Congenital Heart Disease and Consultant Cardiologist, Adult Congenital Heart Centre and Centre for Pulmonary Hypertension, Royal Brompton Hospital, and the National Heart & Lung Institute, Imperial College London, UK

University Printing House, Cambridge CB2 8BS, United Kingdom Cambridge University Press is part of the University of Cambridge. It furthers the University’s mission by disseminating knowledge in the pursuit of education, learning and research at the highest international levels of excellence. www.cambridge.org Information on this title: www.cambridge.org/9781107095946 © Cambridge University Press (2006) 2016 This publication is in copyright. Subject to statutory exception and to the provisions of relevant collective licensing agreements, no reproduction of any part may take place without the written permission of Cambridge University Press. First published: 2006 by RCOG Press Second edition Year 2016 Printed in the United Kingdom by TJ International Ltd. Padstow Cornwall A catalog record for this publication is available from the British Library Library of Congress Cataloging in Publication data Names: Steer, Philip J., editor. | Gatzoulis, Michael A., editor. Title: Heart disease and pregnancy / edited by Philip J. Steer, Philip J. Steer, BSc MD FRCOG, Emeritus Professor, Imperial College London, Academic Department of Obstetrics and Gynaecology, Chelsea and Westminster Hospital, London, UK, Michael A. Gatzoulis, MD PhD FACC FESC, Professor of Cardiology, Congenital Heart Disease and Consultant Cardiologist Adult Congenital Heart Centre and Centre for Pulmonary Hypertension Royal Brompton Hospital, and the National Heart & Lung Institute, Imperial College, London, UK. Description: Second edition. | Cambridge, United Kingdom : Cambridge University Press, 2016. | Includes bibliographical references and index. Identifiers: LCCN 2015041127 | ISBN 9781107095946 (hardback) Subjects: LCSH: Heart diseases in pregnancy. Classification: LCC RG580.H4 H42 2016 | DDC 618.3/61–dc23 LC record available at http://lccn.loc.gov/2015041127 ISBN 978-1-107-09594-6 Hardback Cambridge University Press has no responsibility for the persistence or accuracy of URLs for external or third-party internet websites referred to in this publication, and does not guarantee that any content on such websites is, or will remain, accurate or appropriate. Every effort has been made in preparing this book to provide accurate and up-to-date information which is in accord with accepted standards and practice at the time of publication. Although case histories are drawn from actual cases, every effort has been made to disguise the identities of the individuals involved. Nevertheless, the authors, editors and publishers can make no warranties that the information contained herein is totally free from error, not least because clinical standards are constantly changing through research and regulation. The authors, editors and publishers therefore disclaim all liability for direct or ­consequential damages resulting from the use of material contained in this book. Readers are strongly advised to pay careful attention to information provided by the manufacturer of any drugs or equipment that they plan to use.

Contents List of contributors  vii Preface  ix Consensus statements  x

Section 1 – Pregnancy Counseling and Contraception 1. Preconception counseling for women with cardiac disease  1 Sarah Vause, Sara Thorne, and Bernard Clarke 2. Contraception in women with heart disease  6 Mandish K. Dhanjal

Section 2 – Antenatal Care: General Considerations 3. Cardiovascular changes in normal pregnancy  19 Mark Johnson and Katherine von Klemperer 4. Antenatal care of women with cardiac disease: An obstetric perspective  29 Matthew Cauldwell, Martin Lupton, and Roshni R. Patel 5. Antenatal care of women with cardiac disease: A cardiac perspective  36 Fiona Walker 6. Cardiac monitoring during pregnancy  43 Henryk Kafka, Sonya V. Babu-Narayan, and Wei Li 7. Cardiac drugs in pregnancy  53 Asma Khalil, Gerhard-Paul Diller, and Patrick O’Brien 8. Surgical and catheter intervention during pregnancy in women with heart disease  65 Henryk Kafka, Hideki Uemura, and Anselm Uebing

Section 3 – Antenatal Care: Fetal Considerations 9. Antenatal diagnosis of congenital heart disease  84 Victoria Jowett and Julene S. Carvalho 10. Fetal care and surveillance in women with congenital heart disease  96 Christina K. H. Yu and Tiong Ghee Teoh

Section 4 – Antenatal Care: Specific Maternal Conditions 11. Management of women with prosthetic heart valves during pregnancy  106 Carole A. Warnes 12. Management of aortopathies, including Marfan syndrome and coarctation, in pregnancy  115 Lorna Swan 13. Management of mitral and aortic stenosis in pregnancy  125 Sara Thorne 14. Management of right heart lesions in pregnancy  131 Annette Schophuus Jensen, Lars Søndergaard, and Anselm Uebing 15. Management of pulmonary hypertension in pregnancy  144 David G. Kiely, Charlie A. Elliot, Victoria J. Wilson, Saurabh V. Gandhi, and Robin Condliffe

v

Contents

16. Management of cardiomyopathies in pregnancy  160 Catherine Nelson-Piercy and Catherine Head 17. Management of ischemic heart disease in pregnancy  174 Jolien W. Roos-Hesselink and Iris M. van Hagen 18. Management of maternal cardiac arrhythmias in pregnancy  180 Koichiro Niwa and Chizuko Kamiya 19. Management of maternal endocarditis in pregnancy  191 Stephanie L. Curtis and Graham Stuart 20. Management of women with heart and lung transplantation in pregnancy  199 Coralie Blanche and Maurice Beghetti

Section 5 – Intrapartum Care 21. Pregnancy and cardiac disease: Peripartum aspects  208 David Alexander, Kate Langford, and Martin Dresner

vi

Section 6 – Postpartum Care 22. Management of the puerperium in women with heart disease  218 Margaret Ramsay 23. Impact of pregnancy on long-term outcomes in women with heart disease  227 Henryk Kafka and Natali A. Y. Chung 24. Long-term outcome of pregnancy with heart disease  234 Carole A. Warnes

Appendix A: New York Heart Association classification of cardiovascular disease  240 Appendix B: Antenatal care pathway  241 Index  255 The colour plate section appears between pages 154 and 155.

List of contributors

David Alexander FRCA Department of Anaesthetics, Royal Brompton Hospital, London, UK

Mandish K. Dhanjal BSc MRCP FRCOG Queen Charlotte’s and Chelsea Hospital, Imperial College Healthcare NHS Trust, London, UK

Sonya V. Babu-Narayan BSc MRCP PhD Cardiovascular Biomedical Research Unit, Royal Brompton Hospital and Imperial College, London, UK

Gerhard-Paul Diller MD PhD MSc Division of Adult Congenital & Valvular Heart Disease, University Hospital Münster, Münster, Germany

Maurice Beghetti MD Pediatric Cardiology Unit, Children’s University Hospital, Geneva, Switzerland Coralie Blanche MD Adult Congenital Heart Disease Centre, Royal Brompton Hospital, London, UK Julene S. Carvalho MD PhD FRCPCH Royal Brompton Hospital and Fetal Medicine Unit, St George’s University Hospitals, St George’s University of London, London, UK Matthew Cauldwell BSc MRCOG MRCP MEd Department of Obstetrics & Gynaecology, Chelsea & Westminster Hospital, London, UK Natali A. Y. Chung MD FRCP Department of Cardiology, Guy’s and St Thomas’ NHS Foundation Trust, London, UK Bernard Clarke BSc MD FRCP FESC FACC FRAeS FRCOG(Hon) Department of Cardiology, Manchester Royal Infirmary and Institute of Cardiovascular Sciences, University of Manchester, Manchester, UK

Martin Dresner FRCA Department of Anaesthetics, Leeds Royal Infirmary, Leeds, UK Charlie A. Elliot FRCP Sheffield Pulmonary Vascular Disease Unit, Royal Hallamshire Hospital, Sheffield, UK Saurabh V. Gandhi MD MRCOG Department of Obstetrics & Gynaecology, Royal Hallamshire Hospital, Sheffield, UK Catherine Head MS PhD FRCP Department of Cardiology, Guy’s and St Thomas’ NHS Foundation Trust, London, UK Annette Schophuus Jensen Department of Cardiology, Copenhagen University Hospital, Copenhagen, Denmark Mark Johnson MRCP PhD MRCOG Department of Obstetrics & Gynaecology, Chelsea & Westminster Hospital, London, UK Victoria Jowett MRCPCH Royal Brompton Hospital and Centre of Fetal Care, Queen Charlotte’s & Chelsea Hospital, Imperial College Healthcare NHS Trust, London, UK

Robin Condliffe MD Sheffield Pulmonary Vascular Disease Unit, Royal Hallamshire Hospital, Sheffield, UK

Henryk Kafka MD FRCPC FACC Division of Cardiology, Queen’s University, Kingston, Canada

Stephanie L. Curtis BSc (Hons) MD FRCP Bristol Heart Institute, University Hospitals Bristol NHS Foundation Trust, Bristol, UK

Chizuko Kamiya MD Department of Perinatology, National Cardiovascular Center, Osaka, Japan

vii

List of contributors

Asma Khalil MD MRCOG MSc St George’s Medical School, University of London, London, UK.

Lorna Swan FRCP MD Adult Congenital Heart Disease Unit, Royal Brompton Hospital, London, UK

David G. Kiely MD FCCP Sheffield Pulmonary Vascular Disease Unit, Royal Hallamshire Hospital, Sheffield, UK

Tiong Ghee Teoh MD FRCOG Department of Obstetrics & Gynaecology, Imperial College Healthcare NHS Trust, St Mary’s Hospital, London, UK

Kate Langford MA MD MBA FRCOG Department of Obstetrics & Gynaecology, Guy’s and St Thomas’ Hospitals NHS Trust, London, UK Wei Li MBBS MD PhD FESC FACC Department of Echocardiography, Royal Brompton Hospital, London, UK Martin Lupton MA MRCOG Department of Obstetrics & Gynaecology, Chelsea & Westminster Hospital, London, UK Catherine Nelson-Piercy MA FRCP FRCOG Women’s Health Academic Centre, St Thomas’ Hospital, London, UK Koichiro Niwa MD PhD FACC FAHA FJCC Cardiovascular Center, St Luke’s International Hospital, Tokyo, Japan Patrick O’Brien FRCOG FFSRH FICOG Institute for Women’s Health, University College London Hospitals, London, UK

Sara Thorne MD FRCP Department of Cardiology, University Hospital Birmingham, Birmingham, UK Anselm Uebing MD PhD Adult Congenital Heart Disease Centre, Royal Brompton Hospital, London, UK Hideki Uemura MD MPhil FRCS Department of Cardiothoracic Surgery, Royal Brompton Hospital, London, UK; Congenital Heart Disease Center, Nara Medical University, Nara, Japan Iris M. van Hagen MD Department of Cardiology, Erasmus Medical Center, Rotterdam, Netherlands Sarah Vause MD FRCOG St Mary’s Hospital, Manchester, UK Katherine von Klemperer MRCP Royal Brompton Hospital, London, UK

Roshni R. Patel MSc MRCOG Department of Obstetrics & Gynaecology, Chelsea & Westminster Hospital, London, UK

Fiona Walker FRCP FESC Lead for Pregnancy & Heart Disease Program, UCLH and Barts Health NHS Trust, London, UK

Margaret Ramsay MA MD MRCP FRCOG Department of Obstetrics and Fetomaternal Medicine, Nottingham University Hospitals, Queen’s Medical Centre Campus, Nottingham, UK

Carole A. Warnes MD FRCP Adult Congenital Heart Disease Clinic, Division of Cardiovascular Diseases, Mayo Clinic, Rochester, MN, USA

Jolien W. Roos-Hesselink MD PhD Department of Cardiology, Erasmus Medical Center, Rotterdam, Netherlands

Victoria J. Wilson FRCA Department of Anaesthesia & Critical Care, Royal Hallamshire Hospital, Sheffield, UK

Lars Søndergaard MD Department of Cardiology, Copenhagen University Hospital, Copenhagen, Denmark

Christina K. H. Yu BSc MD MRCOG Department of Obstetrics & Gynaecology, Imperial College Healthcare NHS Trust, St Mary’s Hospital, London, UK

Graham Stuart FRCP FRCPCH Bristol Heart Institute, University Hospitals Bristol NHS Foundation Trust, Bristol, UK

viii

Preface

Since the turn of the twenty-first century, cardiac disease has become the leading medical cause of death in relation to pregnancy in the United Kingdom. In response to this, the meetings committee of the Royal College of Obstetricians and Gynaecologists in London put together an international study group of 28 obstetricians, cardiologists, anesthetists and other experts in related fields to discuss this challenge to maternal health. The group met on February 13–15, 2006 at the RCOG in London, and out of this meeting came the first edition of Heart Disease and Pregnancy, published in the same year. Both the first and second printing sold out, so clearly the book was meeting a need. From 2010 onwards, there were increasing requests for an update to a volume that so many people had found useful. Unfortunately, the RCOG no longer funds such activities; study groups now concentrate on developing research proposals, and the publishing department has been closed, and its booklist transferred to Cambridge University Press. Fortunately, we were able to persuade Cambridge University Press of the need for a second edition, and we are grateful to Nick Dunton for taking our proposals forward to success. In addition, one of us (MAG) runs a regular international meeting on congenital heart disease, and he was able to arrange a consensus session at one of the meetings (held at the Royal College of Surgeons in September 2014) where many of the original participants (and some new ones) gathered together to update the consensus statements. Consensus statements are necessary because there is a paucity of randomized trials in relation to heart disease in pregnancy, and therefore clinical guidelines rely heavily upon expert opinion. Funding for randomized trials or international collaborative studies is difficult to obtain because globally, maternal and child health have a low political priority. In addition, the increasing number of international regulations applying to

any studies involving drug therapy make randomized trials extremely expensive, especially when the conditions studied are individually relatively uncommon. However, the growing number of surviving women with corrected or ameliorated congenital heart disease, and the increasing attempts to improve maternal health globally, means that guidelines are required for the growing number of centers dealing with pregnant women with heart disease. We are grateful to those authors who have updated their previous chapters, and there have been a considerable number of new contributors, who have looked at things afresh, and sometimes contributed entirely new chapters (for example, on transplantation). The chapters are laid out in a way that we hope readers will find intuitive, starting with prepregnancy counseling and contraception, moving through the antenatal period to delivery and the puerperium, and finishing with long-term outcome. There is some overlap between chapters, for example the physiological changes of pregnancy are often recapped at the beginning. The purpose of this is to make each chapter comprehensible in its own right, both for easy initial reading, and for rapid revision. We have done our best to make sure that there is no significant conflict between the content of the various chapters. In the first edition, we had a special section at the end for the consensus statements, both “overarching” and specific to individual chapters. In response to feedback from the many readers who felt the consensus statements were particularly useful, we have now put the overarching statements right at the front of the book, and those that are more specifically condition related are included at the beginning of their appropriate chapters as “practical practice points.” We hope that this innovation will make the book even more useful than the first edition.

ix

Consensus statements

The following consensus statements were drafted at a face to face meeting at the Royal College of Surgeons (London) on September 30, 2014, and subsequently agreed by email. They are followed by the list of participants in the meeting, and a photograph of them on the steps of the Royal College of Surgeons.

Definitions 1. Multidisciplinary Team (MDT). The core members of the MDT should be appropriately trained obstetricians, cardiologists, and anesthetists, and the wider team who should also be involved in care when appropriate may include midwives, neonatologists, intensivists, obstetric physicians, hematologists, specialist nurses and geneticists. 2. A tertiary unit is defined as a hospital (or group of hospitals) able to provide combined obstetric, cardiological, anesthetic and cardiac surgical expertise in the care of women with heart disease. Any tertiary center caring for pregnant women with heart disease should have facilities for prolonged high-level maternal surveillance with direct access to adult critical care facilities.

Overarching consensus views General 1. There should be national and international registries for the collection of data on pregnancy in women with heart disease. These data should be collected centrally to enable a more detailed analysis of risk factors for poor pregnancy and long-term outcomes (including maternal survival and infant disability). Such information would greatly improve the counseling of women with heart disease.

x

2. There should be recognized networks for the provision of care for women with both acquired and congenital heart disease and appropriate referral links should be established. These will need to be specifically funded as the care of these women cannot be provided from routine obstetric and cardiac resources. 3. If any pregnant or postpartum woman has unexpected and persistent cardiorespiratory symptoms she should have thorough evaluation of possible cardiovascular causes such as cardiomyopathy, acute coronary syndrome, aortic dissection and pulmonary embolism.

Preconception 1. A proactive approach to preconception counseling should be started in adolescence (at age 12–15 years, depending on individual maturity) and should include advice on safe and effective contraception. Comprehensive advice should be given at the appropriate age and not delayed until transfer to the adult cardiological services. 2. All women of reproductive age with congenital or acquired heart disease should have access to specialized multidisciplinary preconception counseling with regular reevaluation to enable them to make a fully informed choice about pregnancy. 3. When assisted conception is being planned, the advice of the MDT should be sought before any such treatment is commenced. 4. In counseling women about motherhood, alternatives to the woman carrying the baby herself can be considered (for example surrogacy or adoption). 5. Women with a family history of inherited cardiac conditions should be screened before pregnancy.

Consensus statements

6. Any cardiac surgical interventions in women of childbearing age should take into account the effect they may have on pregnancy. For example, because of the risks associated with prosthetic mechanical valves in pregnancy, consideration should be given to valve repair or using tissue valves for valve replacement. 7. Contraceptive choice for women with heart disease should be tailored to the particular patient, taking into account any increased risks of thrombosis or infection associated with the various contraceptive methods and their interaction with the various heart lesions or drugs being taken.

Antenatal care 1. Once women with heart disease are pregnant, they should be referred to the MDT as soon as possible. The timing and frequency of follow-up visits should be determined by the MDT. Direct self-referral should also be allowed, to avoid delays. 2. Medication should be reviewed and adjusted as necessary. 3. The threshold for starting thromboprophylaxis should be determined by the MDT. 4. Thrombolysis may cause bleeding from the placental site but should be given in women with life-threatening thrombotic disease. 5. Following assessment by the MDT, care can be arranged at a local hospital or tertiary unit (where the MDT is based), according to the complexity of the heart disease, the risk assessment and the locally available facilities and expertise. Shared care between the local and tertiary hospitals may be appropriate, in which case a detailed plan of care should be documented and accessible to all care providers. 6. A copy of the plan should be carried by the woman herself, so it is available in an emergency to care providers other than her usual team. 7. Women with congenital heart disease should be offered fetal echocardiography. 8. Tertiary units should offer a hotel facility to enable women who live some distance from the hospital to stay on site, to avoid (a) a delay in receiving appropriate care when they go into labor and (b) the need to induce labor solely to avoid this risk.

Intrapartum care 1. Management of intrapartum care should be supervised by a team experienced in the care of women with heart disease (obstetrician, anesthetist and midwife), with a cardiologist or appropriately experienced obstetric physician readily available. 2. A clear plan for management of delivery and the puerperium in women with heart disease should be established in advance, be well documented and be distributed widely (including to the woman herself) so that all personnel likely to be involved in the woman’s intrapartum and postpartum care are fully informed. It is recommended that the woman should carry her own notes (or at least a copy of them) at all times. There should be clear arrangements for contacting the MDT in case of an emergency. 3. Vaginal delivery is the preferred mode of delivery over cesarean section for most women with heart disease—whether congenital or acquired—unless obstetric or specific cardiac considerations determine otherwise. This can be facilitated where appropriate by the use of regional anesthesia and assisted vaginal delivery. 4. Induction of labor may be appropriate, to optimize the timing of delivery in relation to anticoagulation and the availability of specific medical staff or because of deteriorating maternal cardiac function. 5. In the management of the third stage of labor in women with heart disease, low-dose oxytocin infusions are safer than bolus doses of oxytocin, which can cause hypotension. Ergometrine is best avoided if systemic hypertension is a concern. Misoprostol is an effective uterotonic although it can cause problems such as hyperthermia. 6. When planning care, specific instructions should be recorded regarding intrapartum antibiotic prophylaxis. There is no evidence that prophylactic antibiotics prevent endocarditis in an uncomplicated vaginal delivery. However, prophylactic antibiotic cover should be given to women undergoing an operative delivery, and to women at increased risk of infectious endocarditis, such as those with mechanical valves or a history of previous endocarditis and to women before any intervention that is likely to be associated with significant or recurrent bacteremia. The possibility of endocarditis should always be borne in mind.

xi

Consensus statements

Postpartum care 1. High-level maternal surveillance is required until the main hemodynamic challenges following delivery have passed. Multidisciplinary

surveillance should be maintained until it is judged the woman is well enough to leave hospital. Follow-up assessment should be arranged by the MDT. Contraceptive advice must be given.

List of participants in the consensus meeting

xii

Adamson

Dawn

Cardiologist

Coventry

Chung

Natali

Cardiologist

Guy’s and St Thomas’

Clarke

Bernard

Cardiologist

Manchester

Curtis

Stephanie

Cardiologist

Bristol

Dhanjal

Mandish

Obstetrician

Queen Charlotte’s Hospital

Gatzoulis

Michael

Cardiologist

Imperial College London

Head

Cathy

Cardiologist

Guy’s and St Thomas’

Jensen

Annette

Cardiologist

Copenhagen, Denmark

Johnson

Mark

Obstetrician

Imperial College London

Kamiya

Chizuko

Cardiologist

Osaka, Japan

Li

Wei

Cardiologist

Royal Brompton Hospital

Nelson-Piercy

Catherine

Obstetric Physician

Guy’s and St Thomas’

Patel

Roshni

Obstetrician

Chelsea and Westminster Hospital

Ramsay

Margaret

Obstetrician

Nottingham

Roos-Hesslink

Jolien

Cardiologist

Rotterdam, Netherlands

Søndergaard

Lars

Cardiologist

Copenhagen, Denmark

Steer

Philip

Obstetrician

Imperial College London

Van Hagen

Iris

Cardiologist

Rotterdam, Netherlands

Vause

Sarah

Obstetrician

Manchester

Von Klemperer

Kate

Cardiologist

Royal Brompton Hospital

Warnes

Carole

Cardiologist

Mayo Clinic, USA

Yu

Chrissie

Obstetrician

St Mary’s Hospital, London

newgenprepdf

Consensus statements

Picture of the participants in the consensus meeting

Figure X.1.  Front row, left to right Michael Gatzoulis, Philip Steer, Mandish Dhanjal, Bernard Clarke, Margaret Ramsay, Natali Chung, Sarah Vause, Jolien Roos-Hesslink, Cathy Nelson-Piercy, Stephanie Curtis Behind, from left Mark Johnson, Roshni Patel, Iris van Hagen, Kate von Klemperer, Chrissie Yu, Dawn Adamson, (partially obscured, Annette Jensen), Carole Warnes, Lars Søndergaard, Kamiya Chizuko, Cathy Head, Wei Li

xiii

Section 1 Chapter

1

Pregnancy Counseling and Contraception

Preconception counseling for women with cardiac disease Sarah Vause, Sara Thorne, and Bernard Clarke

Practical practice points 1. All women of reproductive age with congenital or acquired heart disease should have access to specialized multidisciplinary preconception counseling with regular reevaluation so as to empower them to make choices about pregnancy. 2. Preconception counseling should include assessment and optimization of the woman’s cardiac condition to minimize the risk of pregnancy. 3. Preconception counseling should include a discussion of contraceptive choices, and should be tailored to the woman’s individual medical and social circumstances.

Introduction The majority of women want to have children, and women with heart disease are no exception. Complex heart disease is no bar to sexual activity. Most women with heart disease do have some awareness of the risks of pregnancy but their ideas are often inaccurate, ranging from overly optimistic to overly pessimistic.[1] They may be equally poorly informed about the prognosis of their heart condition, even in the absence of pregnancy. Many doctors do not have a good understanding of the risks of pregnancy in women with heart disease and thus such women may be deprived of appropriate advice and counseling unless a specialist referral is made. In the 2011 UK maternal mortality report, there was some degree of substandard care in 51% of deaths from cardiac causes: lack of preconception care was one aspect identified as substandard. [2] Better provision of preconception care was one of the “top ten recommendations” from this report.[2] Discussions with a cardiologist and/or an obstetric

physician with a specialist interest in pregnancy and heart disease should begin in adolescence. These discussions should cover future pregnancies and their prevention, both to prevent accidental and possibly dangerous pregnancies and to allow patients to come to terms with their future childbearing potential. They also need to be able to plan their families in the knowledge of their likely future health and life expectancy. In the UK, the majority of women seen preconception by cardiologists and/or obstetricians will be women with congenital heart disease (CHD). This is because the incidence of CHD (0.8%) in pregnant women in the UK is higher than the incidence of acquired heart disease (0.1%). Furthermore, most women with CHD are already known to cardiac services, while women with acquired heart disease may be unaware of their condition, or the condition itself may only present during pregnancy or in the postnatal period.

Components of preconception counseling Preconception counseling should ideally [3]: • display attitudes and practices that value pregnant women, children and families and respect the diversity of people’s lives and experiences • incorporate informed choice, thus encouraging women and men to understand health issues that may affect conception and pregnancy • encourage women and men to prepare actively for pregnancy, and enable them to be as healthy as possible • attempt to identify couples who are at increased risk of having babies with a congenital

Heart Disease and Pregnancy, 2nd edn. ed. Philip J. Steer and Michael A. Gatzoulis. Published by Cambridge University Press. © Cambridge University Press 2016.

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Section 1: Pregnancy Counseling and Contraception

abnormality and provide them with sufficient knowledge to make informed decisions. These four components will be discussed below in relation to cardiac disease in pregnancy.

Valuing the cultural background of the woman and her family, and respecting diversity Preconception counseling should display attitudes and practices that value pregnant women, children and families and respect the diversity of people’s lives and experiences. All women have a cultural context within a multicultural society. For some women, issues related to culture may need specific attention, including: • their religious beliefs (particularly in relation to contraception and termination of pregnancy) • the role of the partner and extended family in pregnancy decisions • communication, where English is not the first language. Assumptions are often made about the anticipated views of certain racial, cultural, or religious groups and this may consciously or subconsciously affect the way in which doctors counsel women. Addressing these overtly helps one to compensate for any unintentional bias. All people have a social and emotional context, and when women and their partners seek advice this context must be considered. Their attitudes and expectations are likely to have been influenced by their previous experiences and those of their family. These may include the anxieties of overprotective parents or worries relating to their inability to embark on, or continue, a meaningful relationship if pregnancy is contraindicated. While it is important to explore and respect the context of a woman’s cultural background, preconception counseling should promote the autonomy of the woman. It should enable her to determine her own personal priorities and support her decision-making.

Informed choice and understanding Preconception counseling should provide information in a frank, honest and understandable way so as to give the woman a realistic estimate of both maternal and fetal risk and allow her to make an informed decision as to whether to embark on a pregnancy or not. The counseling should include information on:

2

• the effects of cardiac disease on pregnancy, in terms of both maternal and fetal risks • the effects of pregnancy on cardiac disease, including the risk of dying or long-term deterioration • whether these effects will change with time or treatment • the other options that may be available, such as contraception, surrogacy or adoption • the long-term outlook—a woman with a short life expectancy may feel that pregnancy, surrogacy, or adoption is not appropriate, as a child may then have to deal with the terminal illness and death of the mother. The difficulty for the cardiologist and obstetrician is to provide an accurate assessment of risk. For some complex conditions, there is little or no information available, either because of the rarity of the woman’s disease or because they represent a new cohort of survivors to adulthood with a surgically modified disease. Scoring systems, such as CARPREG (“CARdiac disease in PREGnancy”) and ZAHARA (“Zwangerschap bij Aangeboren HARtAfwijkingen I”), have been devised to predict the chance of maternal cardiac or neonatal complications during pregnancy.[4,5] However, such scoring systems do not predict complications that are specific to certain conditions, e.g. aortic dissection in Marfan syndrome. Perhaps the most important message to take from these scoring systems is which risk factors can be useful in predicting poor outcome. The European Society for Cardiology (ESC) guidelines on cardiovascular diseases in pregnancy provide an overall classification of the risk of maternal mortality and morbidity.[6] For specific conditions, data can be obtained from the literature. However, studies are frequently small, retrospective and derived from women managed in a single center. A literature review of papers relating to pregnancy outcomes in women with structural CHD was published by Drenthen et  al., and informed the ESC guidelines.[6,7] Cardiopulmonary exercise testing has been studied to determine whether the increase in cardiac output during exercise would act as a surrogate for that seen in pregnancy and, therefore, whether it could be used to predict pregnancy outcome. Impaired maximal oxygen uptake and chronotropic response (failure to raise heart rate adequately) during exercise correlate with poor pregnancy outcome,[8] and, therefore, may be included in the preconception assessment. A woman should be informed that the main risks to her include:

Chapter 1: Preconception counseling for women with cardiac disease

• maternal death—the highest risk is in women with pulmonary arterial hypertension; those with poor systemic ventricular function, severe left-sided obstruction and severe aortopathy are also at high risk • arrhythmias (particularly in women with Fontan circulation or atrial repair of transposition of the great arteries), heart failure (particularly in women with pre-existing ventricular impairment with or without coexistent valve disease, ischemic heart disease, cyanotic CHD, a systemic right ventricle or a Fontan circulation), including progression of ventricular dysfunction and permanent deterioration following pregnancy • acute coronary syndrome in women with known pre-existing coronary disease • aortic dissection in women with inherited aortopathies (particularly Marfan and Loeys-Dietz syndromes, but also with bicuspid aortopathy) • thromboembolism (particularly in women with cyanotic CHD, prosthetic valves or a Fontan circulation) • the potential need for earlier intervention for valve disease as a result of pregnancy. The risks to the fetus include the following: • fetal growth restriction, particularly in women taking beta-blockers or with cyanotic heart disease or a Fontan circulation • iatrogenic or spontaneous preterm delivery, which may result in long-term disability in the child • recurrence of CHD (typical risk of 3–5%, but this varies with the type of maternal lesion, and is also related to paternal lesions) or a genetically inherited cardiac condition • teratogenesis or fetotoxicity from drugs, for example from warfarin or angiotensin-convertingenzyme (ACE) inhibitors • fetal loss resulting from invasive prenatal testing. One successful pregnancy should not engender complacency. Some conditions, such as peripartum cardiomyopathy, have a high recurrence risk and preconception counseling before embarking on a subsequent pregnancy is recommended.[2,9] Other conditions can worsen with age and the risks will be higher in each subsequent pregnancy.

Information about contraception and termination Facilitating informed choice also means that doctors must provide information relating to the choice of not

being pregnant. This includes advice about appropriate contraception and information about termination of pregnancy services. The assurance that clinicians will be nonjudgmental and supportive of a decision to terminate a pregnancy is important. Open discussion of these options and provision of contact numbers to facilitate access to these services reinforces that these are options available to the woman.[10] Termination of pregnancy in women with heart disease is not without risks, and it should be performed in a center with appropriate anesthetic and cardiac facilities. Specialist advice on contraception may need to be obtained from specialist sexual health services.

Information about clinical management During the preconception appointment the proposed plan of care for the pregnancy should be outlined. Women with significant cardiac disease should be managed in a center with appropriate expertise, preferably in a joint obstetric–cardiac clinic, even though for some women this may mean traveling long distances. Women should be made aware of how likely, or not, it would be that they would need admission antenatally, iatrogenic preterm delivery, lower segment cesarean section (LSCS) or high dependency care in a hospital that may be many miles from home.

Information in an appropriate language If the woman and her doctor do not speak the same language, a professional interpreter should be employed. Interpreters from within the family, including the husband, should be avoided as in the family’s desire to help the woman have a successful pregnancy the risks may not be accurately relayed to her. This has been a recommendation from three UK maternal mortality reports. [2,10,11]

Preparing for pregnancy The preconception consultation provides the ideal opportunity to minimize risks and optimize cardiac function before pregnancy [12]: • valvotomy, valve repair or replacement before pregnancy—if valve replacement is performed, the choice of the type of valve used may be influenced by the desire for future pregnancy. Risks should be balanced between the use of tissue valves, obviating the need for anticoagulation during pregnancy but carrying the risk of inevitable reoperation, and the use of mechanical valves,

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Section 1: Pregnancy Counseling and Contraception

mandating the use of anticoagulation during pregnancy, but (potentially) obviating the need for future surgery • treatment of arrhythmias (interventional or medical) • treatment of underlying medical conditions, such as hypertension or diabetes • avoidance of teratogens—medication may need to be changed before pregnancy • discussion about anticoagulation—women using warfarin need to be aware of its teratogenic potential and the risk of fetal intracranial hemorrhage, and should understand the advisability in most cases for conversion to heparin once pregnancy is confirmed. Contact numbers should be provided to facilitate this as early as possible in pregnancy. For women with mechanical valves, the risks of warfarin vs the risks of low-molecular-weight heparin should be discussed to enable them to make an informed choice about which anticoagulant regime should be used during pregnancy • dental treatment—women with complex heart disease may need to be referred to a tertiary dental hospital for dental care. It is preferable for any dental problems to be addressed and resolved before pregnancy • timing of pregnancy—for those with progressive disease (e.g. a systemic right ventricle or univentricular heart), pregnancy is likely to be tolerated better when the woman is younger. Such women should be discouraged from purposely delaying pregnancy because of other considerations such as a career • contraception—until the above cardiac problems have been appropriately addressed, the provision of appropriate contraception is paramount • general prepregnancy advice should not be forgotten, for example taking folic acid to reduce the risk of neural tube defect in the baby, smoking cessation, weight management etc. • provision of phone numbers to facilitate prompt contact and reassessment once pregnancy is confirmed. Women undergoing assisted conception often have additional risk factors such as increased age and the risk of ovarian hyperstimulation and multiple pregnancy, with a concomitant increase in the risk of

4

preeclampsia. These conditions can compound the risk of heart disease, and ovarian hyperstimulation may be fatal in women with impaired ventricular function or a Fontan circulation. In women undergoing assisted conception, it is important that precautions should be taken to avoid hyperstimulated cycles and to minimize the chance of multiple pregnancy by carrying out single-embryo replacements during in vitro fertilization (IVF) cycles.

Risk of congenital abnormality Many couples have worries about the risk of CHD in their unborn baby. For the majority of women with CHD (with no family history and no chromosomal abnormality), the risk of recurrence of CHD in the fetus is around 3–5%. Prenatal fetal echocardiography should be arranged and couples can be reassured that the most likely outcome is a healthy baby. For women known to have, or suspected of having, a genetically inherited cardiac condition, the preconception appointment offers the opportunity to refer a woman to a clinical geneticist. Tetralogy of Fallot, when associated with underlying genetic disorders such as 22q11.2 deletion (DiGeorge syndrome), carries a much higher recurrence risk than when tetralogy of Fallot occurs in the absence of an underlying genetic syndrome. It can be difficult for most clinicians to recognize rare genetic syndromes, so doctors should have a low threshold to make a genetics referral, especially if there is a family history of CHD. Although a woman may have previously been seen by a geneticist, she may welcome the opportunity to discuss the risks to the fetus again once she begins to contemplate pregnancy. Preconception care should also include a discussion of the various prenatal tests available for the detection of fetal abnormality, their risks and limitations, the timing of the tests, and the way in which they are performed. Information about how to access these tests, including contact numbers, should be provided. Discussion should include the options available, including termination, if the fetus is found to be abnormal. Women should be encouraged to carefully consider the implications of testing, and whether they would terminate the pregnancy if the baby is found to be abnormal, prior to embarking on testing (the choice may vary according to the nature of the fetal abnormality).

Chapter 1: Preconception counseling for women with cardiac disease

For women with conditions such as Marfan syndrome, the preconception appointment offers the opportunity to discuss the risk that their baby will be affected (which is 50% as it is a single dominant gene abnormality, assuming the father is unaffected) and whether they would like early screening, for example preimplantation diagnosis (which requires IVF), or no screening at all. If a decision for no screening is made, the infant needs to be followed up postnatally to establish a diagnosis. If Marfan syndrome is diagnosed, long-term surveillance needs to be implemented.

Conclusion Successful preconception counseling will empower a woman with cardiac disease to make informed choices relating to pregnancy by providing nondirective counseling and access to the appropriate multidisciplinary specialized services. Optimizing her health before pregnancy will improve the likelihood of a successful pregnancy outcome.

References 1. Moons P, De Volder E, Budts W, et al. What do adult patients with congenital heart disease know about their disease, treatment and prevention of complications? A call for structured patient education. Heart 2001;86:74–80. 2. Cantwell R, Clutton-Brock T, Cooper G. Saving Mothers’ Lives: Reviewing maternal deaths to make motherhood safer: 2006–2008. The Eighth Report of the Confidential Enquiries into Maternal Deaths in the United Kingdom. BJOG 2011;118(Suppl. 1):1–203. 3. Health Canada. Family-Centred Maternity and Newborn Care: National Guidelines. Ottawa: Ministry of Public Works and Government Services; 2000 [www.hc-sc. gc.ca]

4. Siu SC, Sermer M, Colman JM, et al. Prospective Multicenter Study of Pregnancy Outcomes in Women With Heart Disease Circulation 2001;104;515–21. 5. Drenthen W, Boersma E, Balci A, et al. Predictors of pregnancy complications in women with congenital heart disease. Eur Heart J 2010;31:2124–32. 6. European Society of Gynecology (ESG), Association for European Paediatric Cardiology (AEPC), German Society for Gender Medicine (DGesGM), et al. ESC Guidelines on the management of cardiovascular diseases during pregnancy: The Task Force on the Management of Cardiovascular Diseases during Pregnancy of the European Society of Cardiology (ESC). Eur Heart J 2011;32:3147–97. 7. Drenthen W, Pieper PG, Roos-Hesselink JW, et al. on behalf of the ZAHARA Investigators. Outcome of pregnancy in women with congenital heart disease: A literature review. JACC 2007;49 (24):2303–11. 8. Lui GK, Silversides CK, Khairy P, et al. Alliance for Adult Research in Congenital Cardiology (AARCC). Heart rate response during exercise and pregnancy outcome in women with congenital heart disease. Circulation 2011;123:242–8. 9. Elkayam U, Tummala PP, Rao K, et al. Maternal and fetal outcomes of subsequent pregnancies in women with peripartum cardiomyopathy. N Engl J Med 2001;344:1567–71. 10. Drife JO, Lewis G, Clutton-Brock T, eds. Why Mothers Die: The Sixth Report of the Confidential Enquiries into Maternal Deaths in the United Kingdom 2000–2002. London: RCOG Press; 2004. 11. Lewis G, ed. Saving Mothers’ Lives: Reviewing maternal deaths to make motherhood safer 2003– 2005. The Seventh Report on Confidential Enquiries into Maternal Deaths in the United Kingdom. London: CEMACH 2007. 12. Thorne SA. Pregnancy in heart disease. Heart 2004;90:450–6.

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Section 1 Chapter

2

Pregnancy Counseling and Contraception

Contraception in women with heart disease Mandish K. Dhanjal

Practical practice points 1. A key requirement for contraception in women with severe heart disease is maximum efficacy because the consequences of contraceptive failure can be fatal. 2. Subdermal progestogen implants (such as Nexplanon®) and progestogen-loaded intrauterine devices (such as Mirena®) are the most efficacious forms of contraception and are also safe methods for most women with significant heart disease. 3. In the event of unprotected sexual intercourse, women with heart disease should be aware that emergency contraception, known to be safe for women with heart disease, is available. 4. Urgent access to termination of pregnancy should be readily available within a hospital equipped to deal with the woman’s cardiac condition.

has been incorporated into the subsequently developed UK Medical Eligibility Criteria (UKMEC) shown in Table 2.1.[3] The UKMEC classification for an individual agent will vary according to circumstance and concomitant medical illnesses such as cardiac disease, hypertension, and diabetes. For example, a woman starting the combined oral contraceptive (COC) pill will be classified as: • UKMEC 1 if she is aged under 40 years • UKMEC 2 if she is aged 40 years or older • UKMEC 3 if she has adequately controlled hypertension • UKMEC 4 if she is hypertensive with systolic blood pressure ≥160 mmHg or diastolic blood pressure ≥95 mmHg.

Introduction

Counseling patients on the risks of pregnancy

Cardiac disease is the main cause of maternal mortality in the UK, being responsible for 20% of maternal deaths.[1] The major pathologies causing mortality are cardiomyopathy (mainly peripartum cardiomyopathy), ischemic heart disease, sudden adult death syndrome, and dissection of the thoracic aorta. There are a handful of cardiac conditions in which pregnancy is not advisable because of mortality rates approaching 25%. It is imperative that women with these conditions have the most reliable methods of contraception available. However, contraceptive agents may themselves influence heart disease or may interact with medications used by such women. The World Health Organization (WHO) has classified contraceptive agents into four classes depending on their suitability for use in medical conditions (WHO Medical Eligibility Criteria [WHOMEC]).[2] This classification

Adolescents with congenital heart disease (CHD) should have the issue of pregnancy and contraception discussed with them at age 12–15 years (depending on the individual’s maturity). This will usually take place in the pediatric cardiology clinic. Transition from pediatric to adult services should include information about the individual’s cardiac disease, her risks from pregnancy, and her risks from contraceptive use, specifically of venous thrombosis, severe vasovagal reaction, and endocarditis.[4] Suitable contraception should be offered to all women with heart disease who are sexually active and who either do not yet wish to conceive or for whom pregnancy is not advisable. Any competent young person in the UK can consent to medical treatment. If they are under 16 years old their parents or carers should be informed, although if it is judged that providing contraception is in the best interest of an adolescent

Heart Disease and Pregnancy, 2nd edn. ed. Philip J. Steer and Michael A. Gatzoulis. Published by Cambridge University Press. © Cambridge University Press 2016.

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Chapter 2: Contraception in women with heart disease

Table 2.1  WHOMEC and UKMEC classification and interpretation of medical eligibility for contraceptives

WHOMEC/UKMEC class

Eligibility for contraceptives with medical conditions

“ABCD” classification

1

No restriction for use

Always usable

2

Advantages of method generally outweigh theoretical or proven risk

Broadly usable

3

Theoretical or proven risks generally outweigh advantages

Caution/counseling

4

Unacceptable health risk

Do not use

UKMEC = UK Medical Eligibility Criteria; WHOMEC = World Health Organization Medical Eligibility Criteria Adapted from World Health Organization and Faculty of Sexual & Reproductive Healthcare [2,3] Table 2.2  Classification of medical illness (e.g. heart disease) according to risk to maternal health if pregnant

Class

Risk of maternal morbidity and mortality resulting from pregnancy with medical illness

Counseling required if pregnancy considered

1

No detectable increased risk

No contraindication to pregnancy

2

Slightly increased risk

Can consider pregnancy

3

Significantly increased risk

If pregnancy still desired after counseling, intensive specialist cardiac and obstetric monitoring will be required antenatally, in labor and postnatally

4

Unacceptably high risk

Pregnancy not advisable; offer emergency contraception or termination if pregnancy occurs; if declined care for as class 3

Adapted from Thorne et al. [5]

who understands the information given then parental (or carer) consent is not required. All women with heart disease considering pregnancy should be offered preconception counseling. In women with CHD, counseling should be provided by a specialist in adult CHD in tandem with an appropriately experienced obstetrician. A risk assessment should be carried out to specifically ascertain cardiovascular and cerebrovascular risk factors, history of hypertension, thrombosis, and migraines, smoking status, and personal or family history of thrombophilia, hyperlipidemia, stroke, and diabetes. A similarly thorough assessment is necessary before prescribing contraception. The WHO classification for contraceptives can be extended and adapted to cover the risk of maternal morbidity and mortality resulting from pregnancy in women with specific medical conditions, such as heart disease (Table 2.2).[5] Fetal consequences should also be taken into consideration when discussing whether pregnancy is advisable. Heart disease causing cyanosis can result in chronic fetal hypoxia that significantly reduces the chances of a live birth. A prepregnancy resting arterial oxygen saturation of 85–90% is associated with a 45% chance of a live birth, but this drops to only 12% with oxygen saturation 70% of their maximum predicted HR and 20% of their study group were within 10% of their maximum. It is currently unknown how far cardiac output rises during active pushing. Analgesia and anesthesia can also alter maternal hemodynamics peri-delivery.[60] The acute sympathetic blockade of regional anesthesia often causes a transient initial hypotension due to acute arterial, arteriolar, and venous dilatation. Subsequently, the decreased cardiac preload and attenuated blood pressure and heart-rate response associated with epidural anesthesia leads to increased hemodynamic stability during labor. (Anesthesia is discussed in more detail in Chapter  21.) Delivery is typically associated with a blood loss of approximately 500–1000 ml. Yet, due to the volume expansion in pregnancy and the fall in volume of the circulation due to the contraction of the uterus and placental bed after delivery of the baby, this has very little effect on blood pressure. However, immediately after delivery, there is a dramatic increase in stroke volume and cardiac output because aortocaval compression is removed and blood is no longer diverted to the uteroplacental circuit.[47]

Clinical implications Women with a “fragile aorta” (e.g. with Marfan or Loeys-Dietz syndrome) are vulnerable to the hypertensive state and to the increased workload of delivery, particularly during active pushing. Therefore, we advise epidural analgesia to control the hypertensive response to pain and we limit the active pushing phase to 20 min

25

Section 2: Antenatal Care: General Considerations

before offering assisted delivery. Women who are unable to cope with increased preload (e.g. those with pulmonary hypertension, left ventricular outflow tract obstruction, or cardiomyopathy) may develop right or left heart failure with the dramatic increase in preload postdelivery. For this reason, such patients need very careful hemodynamic monitoring, preferably in a high dependency unit, for 12–24 h postdelivery.

Postpartum Robson demonstrated a dramatic fall in stroke volume after delivery, coinciding with an increase in ANP levels, which play a part in the diuresis that typically starts within 24 h of delivery. HR has been shown to decrease more gradually (by 20%) over 10 days postdelivery.[61,62] Capeless and Clapp showed, however, that the vascular remodeling of pregnancy persists for an extended period of time; in their study the vascular parameters described in this chapter had not reached the prepregnancy baseline up to a year after delivery. [45,63] This is important because many of the studies of hemodynamic change in pregnancy have used postpartum values (taken as early as 6 weeks) as surrogates for baseline, which makes them difficult to interpret. There have not been any significant hemodynamic differences shown between women who do and do not breastfeed.[62]

Conclusion Pregnancy is associated with an early decrease in SVR that facilitates a progressive increase in circulating blood volume. Cardiac output is increased by the increased preload and decreased afterload, as well as by ventricular remodeling and changes in the renin–angiotensin–aldosterone system. The response to pregnancy is not uniform. Although knowledge has improved since the work of Angus Macdonald, it has not improved as much as for other cardiovascular challenges. For example, we know more about the cardiovascular changes in ischemic heart disease than in pregnancy. There remains a need for well-powered longitudinal studies of pregnancy-related cardiovascular changes in women with and without cardiac disease.

References 1. Macdonald A. The Bearings of Chronic Disease of the Heart Upon Pregnancy, Parturition, and Childbed, London: J&A Churchill; 1878.

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2. Clapp JF 3rd, Seaward BL, Sleamaker RH, Hiser J. Maternal physiologic adaptations to early human pregnancy. Am J Obstet Gynecol 1988;159(6):1456–60. 3. Capeless EL, Clapp JF. Cardiovascular changes in early phase of pregnancy. Am J Obstet Gynecol 1989;161(6 Pt 1):1449–53. 4. Jauniaux E, Johnson MR, Jurkovic D, Ramsay B, Campbell S, Meuris S. The role of relaxin in the development of the uteroplacental circulation in early pregnancy. Obstet Gynecol 1994;84(3):338–42. 5. McGuane JT, Debrah JE, Debrah DO, et al. Role of relaxin in maternal systemic and renal vascular adaptations during gestation. Ann N Y Acad Sci 2009;1160:304–12. 6. Paller MS. Mechanisms of decreased pressor responsiveness to ANG II, NE and vasopressin in pregnant rats. Am J Physiol 1984;247:H100–8. 7. Podjarney E, Mandelbaum A, Bernheim J. Does nitric-oxide play a role in normal pregnancy and pregnancy-induced hypertension? Nephrol Dial Transplant 1994;9:1527–40. 8. Myatt L, Brewer A, Brockman DE. The action of nitric oxide in the perfused human fetal-placental circulation. Am J Obstet Gynecol 1991;164:687–92. 9. Valensise H, Novelli GP, Vasapollo B, Borzi M, Arduini D, Galante A, et al. Maternal cardiac systolic and diastolic function: Relationship with uteroplacental resistances. A Doppler and echocardiographic longitudinal study. Ultrasound Obstet Gynecol 2000;15:487–97. 10. Duvekot JJ, Cheriex EC, Pieters FA, et al. Early pregnancy changes in hemodynamics and volume homeostasis are consecutive adjustments triggered by a primary fall in systemic vascular tone. Am J Obstet Gynecol 1993;169:1382–92. 11. Robson SC, Hunter S, Boys RJ, Dunlop W. Serial study of factors influencing changes in cardiac output during human pregnancy. Am J Physiol 1989;256:H1060–5. 12. Mabie WC, DiSessa TG, Crocker LG, Sibai BM, Arheart KL. A longitudinal study of cardiac output in normal human pregnancy. Am J Obstet Gynecol 1994;170:849–56. 13. Jensen E, Wood C, Keller-Wood M. The normal increase in adrenal secretion during pregnancy contributes to maternal volume expansion and fetal homeostasis. J Soc Gynecol Investig 2002;9:362–71. 14. Longo LD. Maternal blood volume and cardiac output during pregnancy: A hypothesis of endocrinologic control. Am J Physiol 1983;245:R720–9. 15. Crane MG, Harris JJ. Plasma rennin activity and aldosterone excretion rate in normal subjects. II. Effect

Chapter 3: Cardiovascular changes in normal pregnancy

of oral contraceptive agents. J Clin Endocrinol Metab 1969;29:558–62. 16. Lund CJ, Donovan JC. Blood volume during pregnancy. Am J Obstet Gynecol 1967;98:393–403. 17. Ueland K. Maternal cardiovascular dynamics. VII. Intrapartum blood volume changes. Am J Obstet Gynecol 1976;126:671–7. 18. Jansen AJ, van Rhenen DJ, Steegers EA, Duvekot JJ. Postpartum hemorrhage and transfusion of blood and blood components. Obstet Gynecol Surv 2005;60(10):663. 19. Rovinsky JJ, Jaffin H. Cardiovascular hemodynamics in pregnancy. I. Blood and plasma volumes in multiple pregnancy. Am J Obstet Gynecol 1965;93:1–15. 20. Robson SC, Hunter S, Boys RJ, Dunlop W. Hemodynamic changes during twin pregnancy. A Doppler and M-mode echocardiographic study. Am J Obstet Gynecol 1989 Nov;161(5):1273–8. 21. Pieters LLH, Verkeste CM, Saxena PR, et al. Relationship between maternal hemodynamics and hematocrit and hemodynamic effects of isovolemic hemodilution and hemoconcentration in the awake late-pregnant guinea pig. Pediatr Res 21:584, 1987. 22. Sala C, Campise M, Ambroso G, et al. Atrial natriuretic peptide and hemodynamic changes during normal human pregnancy. Hypertension 1995;25:631–6. 23. Chapman AB, Abraham WT, Zamudio S, et al. Temporal relationships between hormonal and hemodynamic changes in early human pregnancy. Kidney Int 1998;54:2056–63.

30. De Paco C, Kametas N, Rencoret G, et al. Maternal cardiac output between 11 and 13 weeks of gestation in the prediction of preeclampsia and small for gestational age. Obstet Gynecol 2008;111:292–300. 31. Duvecot J, Peeters L. Very early changes in cardiovascular physiology. In: Chamberlain G, Broughton-Pipkin F, eds. Clinical physiology in obstetrics, 3rd ed. Malden, MA: Blackwell Science; 1998. pp. 3–32. 32. Atkins AFJ, Watt JM, Milan P, Davies P, Crawford JS. A longitudinal study of cardiovascular dynamic changes throughout pregnancy. Eur J Obstet Reprod Biol 1981;12:215–24. 33. Katz R, Karliner JS, Resnik R. Effects of a natural volume overload state (pregnancy) on left ventricular performance in normal human subjects. Circulation 1978;5:434–41. 34. Veille JC, Morton MJ, Burry KJ. Maternal cardiovascular adaptations to twin pregnancy. Am J Obstet Gynecol 1985;153:261–3. 35. Bosio PM, McKenna PJ, Conroy R, O’Herlihy C. Maternal central hemodynamics in hypertensive disorders of pregnancy. Obstet Gynecol 1999; 94(6):978–84. 36. Kametas NA, McAuliffe F, Cook B, Nicolaides KH, Chambers J. Maternal left ventricular transverse and long-axis systolic function during pregnancy. Ultrasound Obstet Gynecol 2001;18:467–74. 37. Desai DK, Moodley J, Naidoo DP. Echocardiographic assessment of cardiovascular hemodynamics in normal pregnancy. Obstet Gynecol 2004;104:20–9.

24. Lowe, SA, Macdonald GJ, Brown, MA. Regulation of atrial natriuretic peptide in pregnancy: Response to posture. Am J Obstet Gynecol 1991 165:591–5.

38. van Oppen AC, Stigter RH, Bruinse HW. Cardiac output in normal pregnancy: A critical review. Obstet Gynecol 1996;87:310–18.

25. Davison JM. Kidney function in pregnant women. Am J Kidney Dis 1987:9:248–52.

39. Bamfo JE, Kametas NA, Turan O, Khaw A, Nicolaides KH. Maternal cardiac function in fetal growth restriction. BJOG 2006;113(7):784–91.

26. Quinn J, Von Klemperer K, Brooks R, Peebles D, Walker F, Cohen H. Use of high intensity adjusted dose low molecular weight heparin in women with mechanical heart valves during pregnancy: A single-center experience. Haematologica 2009;94(11):1608–12. 27. Shotan A, Ostrzega E, Mehra A, et al. Incidence of arrhythmias in normal pregnancy and relation to palpitations, dizziness, and syncope. Am J Cardiol 1997;79:1061–4. 28. Gowda R M, Khan I A, Mehta N J, et al. Cardiac arrhythmias in pregnancy: Clinical and therapeutic considerations. Int J Cardiol 2003;88:129–33. 29. Bamfo JE, Kametas NA, Nicolaides KH, Chambers JB. Maternal left ventricular diastolic and systolic long-axis function during normal pregnancy. Eur J Echocardiogr 2007;8:360–68.

40. Estensen ME, Beitnes J, Grindheim G, et al. Altered left ventricular contractility and function during normal pregnancy. Ultrasound Obstet Gynecol 2013;41:659–66. 41. Savu O, Jurcut R, Giusca S, et al. Morphological and functional adaptation of the maternal heart during pregnancy. Circ Cardiovasc Imaging 2012;5:289–97. 42. Mesa A, Jessurun C, Hernandez A, et al. Left ventricular diastolic function in normal human pregnancy. Circulation 1999;99:511–17. 43. Geva T, Mauer MB, Striker L, Kirshon B, Pivarnik JM. Effects of physiologic load of pregnancy on left ventricular contractility and remodeling. Am Heart J 1997;133:53–9. 44. Gilson GJ, Samaan S, Crawford MH, et al. Changes in hemodynamics, ventricular remodeling,

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45. 46.

47. 48.

49.

50.

51. 52. 53.

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and ventricular contractility during normal pregnancy: A longitudinal study. Obstet Gynecol 1997;89:957–62. Capeless EL, Clapp JF. When do cardiovascular parameters return to their preconceptional values? Am J Obstet Gynecol 1991;165:683–6. Rossi A, Cornette J, Johnson MR, et al. Quantitative cardiovascular magnetic resonance in pregnant women: Cross-sectional analysis of physiological parameters throughout pregnancy and the impact of the supine position. J Cardiovasc Magn Reson 2011;13:31. Duvekot JJ1, Peeters LL. Maternal cardiovascular hemodynamic adaptation to pregnancy. Obstet Gynecol Surv 1994;49(12 Suppl):S1–14. Lang RM, Bierig M, Devereux RB, et al. Recommendations for chamber quantification: A report from the American Society of Echocardiography’s Guidelines and Standards Committee and the Chamber Quantification Writing Group, developed in conjunction with the European Association of Echocardiography, a branch of the European Society of Cardiology. J Am Soc Echocardiogr 2005;18:1440–63. Simmons LA, Gillin AG, Jeremy RW. Structural and functional changes in left ventricle during normotensive and preeclamptic pregnancy. Am J Physiol Heart Circ Physiol 2002;283:H1627–33. Ducas RA, Elliott JE, Melnyk SF, et al. Cardiovascular magnetic resonance in pregnancy: Insights from the cardiac hemodynamic imaging and remodeling in pregnancy (CHIRP) study. J Cardiovasc Magn Reson 2014;16(1):1. Clark SL, Cotton DB, Lee W, et al. Central hemodynamic assessment of normal term pregnancy. Am J Obstet Gynecol 1989;161:1439–42. Adduljabbar HS, Marzouki KM, Zawawi TH, Kahn AS. Pericardial effusion in normal pregnant women. Acta Obstet Gynecol Scand 1991;70:291–4. Campos O. Doppler echocardiography during pregnancy: physiological and abnormal findings. Echocardiography 1996;13:135–46.

54. Zentner D, du Plessis M, Brennecke S, et al. Deterioration in cardiac systolic and diastolic function late in normal human pregnancy. Clin Sci (Lond) 2009;116:599–606. 55. Robson SC, Dunlop W, Boys RJ, et al. Cardiac output during labour. Br Med J (Clin Res Ed) 1987;295:1169–72. 56. Lee W, Rokey R, Miller J, Cotton DB Maternal hemodynamics effects of uterine contractions by M-mode and pulsed-Doppler echocardiography. Am J Obstet Gynecol 1989;161:974–7. 57. Ueland K, Hansen JM. Maternal cardiovascular dynamics. 3. Labour and delivery under local and caudal analgesia. Am J Obstet Gynecol 1969;103:8–18. 58. Bonica JJ, McDonald JS. Principles and Practice of Obstetric Analgesia and Anesthesia, 2nd edn. Baltimore: Williams & Wilkins; 1994. 59. Adams JG, Alexander AM. Alterations in cardiovascular physiology during labor. Obstet Gynecol 1958;12:542–9. 60. Söhnchen N1, Melzer K, Tejada BM, et al. Maternal heart rate changes during labour. Eur J Obstet Gynecol Reprod Biol 2011;158(2):173–8. 61. Pouta AM, Raasanen JP, Airaksinen KEJ, et al. Changes in maternal heart dimensions and plasma atrial natriuretic peptide levels in the early puerperium of normal and preeclamptic pregnancies. BJOG 1996;103(10):988–92. 62. Robson SC, Hunter S, Moore M, Dunlop W. Haemodynamic changes during the puerperium: A Doppler and M-mode echocardiographic study. Br J Obstet Gynaecol 1987;94:1028–39. 63. Clapp JF III, Capeless E. Cardiovascular function before, during and after the first and subsequent pregnancies. Am J Cardiol 1997;80:1469–73.

Section 2 Chapter

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Antenatal Care: General Considerations

Antenatal care of women with cardiac disease: An obstetric perspective Matthew Cauldwell, Martin Lupton, and Roshni R. Patel

Practical practice points 1. The obstetrician/multidisciplinary team must be meticulous when booking a cardiac patient into the antenatal clinic. They must have access to all relevant hospital notes and recent investigations. 2. Patients with congenital heart disease may have been operated on as children and may have been “lost to follow-up” or be unable to provide a clear history. It is therefore highly important to gather all background information (cardiac anatomy/ diagnosis, interventions, and current physiology/ clinical status) in a timely fashion in order to be able to plan their antenatal care effectively. 3. Prepregnancy counseling for women with heart disease should ideally have taken place prior to the first antenatal visit. Pregnant women with heart disease, nevertheless, need to be risk stratified and a discussion regarding the risk of the pregnancy to the mother and fetus should take place and be documented in the antenatal notes. 4. Antenatal care for women with cardiac disease should take place in centers with appropriate expertise and the need for this should be explained to the patient.

Introduction The burden of heart disease continues to grow in obstetric practice. The reasons for this are a combination of societal change and medical intervention. In the developed world at least, women are increasingly older and more likely to have acquired heart disease by the time they reproduce. Additionally, those born with congenital heart disease (CHD) are more likely to survive into adult life and desire a pregnancy.[1]

Ever since the work of medical pioneers such as Dr Forest Dewey Dodrill, who is credited with the development of the first operational mechanical heart used to allow the performance of open heart surgery in 1952, cardiac surgery has undergone a revolution. His device, alongside other new cardiothoracic interventions and improved medications, has led to a large cohort of people with congenital heart disease (CHD) surviving into adult life. Today about 85% of children born with structural heart disease will survive to adulthood. CHD comprises more than half of all cardiac disease seen in pregnancy. The UK Department of Health has estimated that there are about 135 000 young people and adults in England living with CHD.[2] Half of these adults will be women, most of reproductive age, and many will wish to have children. Since the 1950s, the capacity of medicine to “do things to people” has accelerated and the philosophical framework within which medicine is practiced has also undergone startling changes. The most significant change has been the ascendancy of the principle of patient autonomy and the rapid demise of medical paternalism. Obstetrics has had to confront this philosophical paradigm shift more directly than most other specialties. For example, it is no longer considered appropriate for the obstetrician alone to decide what risks it is reasonable for a woman to undertake. Her own opinion is now the key determinant of the choice that she will make. Who other than the woman, it is argued, can know whether a 30% risk of death is reasonable to accept in order to create a new life? The obstetrician’s role is therefore complex. A  modern obstetrician needs to be an educator, counselor, facilitator, and coordinator. Interestingly, this concept of the obstetrician resonates with the original meaning of the

Heart Disease and Pregnancy, 2nd edn. ed. Philip J. Steer and Michael A. Gatzoulis. Published by Cambridge University Press. © Cambridge University Press 2016.

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word “obstetric,” which is derived from the Latin word “obstare,” meaning “to stand by or next to.” When caring for pregnant women with cardiac conditions, the obstetrician needs to remember two things. The first is that women with heart disease can die or suffer long-term harm during pregnancy if they are not properly cared for. The second is that women with heart disease can die or suffer long-term harm during pregnancy even if their care is exemplary. In the 2011 UK Confidential Enquiry into Maternal Deaths, cardiac disease was found to be the major single cause of maternal death in the UK.[3] If the mother does die, the obstetrician will be held to account for her care. It is therefore in the interests of the obstetrician, as well as of the woman, to make use of the best available multidisciplinary advice at all stages in her pregnancy. It is vital for the obstetrician to be aware of the basic cardiovascular physiology of pregnancy because this poses a major challenge to women with heart disease who become pregnant.

Hemodynamic changes in normal pregnancy Pregnancy causes major cardiovascular changes in healthy women. However, these changes may be poorly tolerated by women with cardiac disease. These are dealt with in detail in Chapter 3 but for convenience a summary is given here. During pregnancy there is a 50% increase in cardiac output, taking place mainly over the first and second trimesters.[4] Despite this increase, blood pressure initially falls, secondary to an even greater fall in peripheral resistance; it then rises again from approximately 34 weeks of gestation. The fall in peripheral resistance drives an increase in plasma volume of 40–45% of the prepregnancy volume.[5–7] There is also a corresponding increase in pulmonary blood flow, which in normal pregnancy does not lead to an increase in pulmonary artery pressure because it is balanced by a decrease in pulmonary vascular resistance.[8] Significant structural changes to the heart during the third trimester include myocardial hypertrophy, chamber enlargement, and mild multivalvar regurgitation. During labor, cardiac output is increased by a further 10–40% above the prelabor level, with up to 500 ml blood joining the circulation with each contraction even in women with effective anesthesia.[9] There are also significant and rapid volume shifts in the first 2 weeks postpartum.[10] Women are also six times more likely to have a thrombosis during pregnancy and 11 times more likely

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to have a thrombosis in the immediate puerperium. This is due to the activation of the coagulation cascade and is a normal physiological process. The likelihood of thrombosis is further increased in the presence of secondary erythrocytosis due to cyanotic heart disease. This hypercoagulable state is of particular importance in women who require anticoagulation even when they are not pregnant. Clearly, each of these changes to the cardiovascular system has the potential to affect women with heart disease and lead to cardiac decompensation. Most obstetricians are familiar with the normal physiology of pregnancy but are less comfortable with the altered physiology induced by cardiac disease.

Recognition of the cardiac condition Most women with CHD will already be aware of their diagnosis although this is not always the case. For example, sudden death in young athletes is most commonly the result of undiagnosed cardiac disease.[11] Given that the incidence of serious maternal morbidity in cardiac disease has been shown to be around 2.3 per 10 000 deliveries with a high case fatality rate of 13%,[12] all women booking for antenatal care should have a “cardiac history” taken. The key questions to ask are [13]: 1. Do you ever suffer from chest pain? 2. Do you have severe breathlessness? 3. Do you have prolonged or symptomatic palpitations? 4. Do you have a history of syncope? 5. Do you have any family history of heart disease or sudden death? Once the cardiac history has been taken, the woman should be examined. Signs such as clubbing of the fingers and cyanosis should be looked for. Her blood pressure should be measured with care, and should be recorded clearly. (The British Hypertension Society recommends using Korotkoff sounds 1 and 5, measured to the nearest 2 mmHg, with the woman seated comfortably and the arm cuff at the level of the atria. [14]) It is important that the blood pressure is taken manually because most automated blood pressure measuring devices are not calibrated correctly for pregnancy and can under-read the true blood pressure by as much as 30 mmHg. See also Beevers et al. [15] and the BHS video tutorial.[16] The woman’s urine should be tested for protein, and her heart and lungs should be auscultated. If a murmur

Chapter 4: Antenatal care of women with cardiac disease: An obstetric perspective

is heard, the obstetrician must decide whether it is physiological or pathological. If the murmur is diastolic, it is considered pathological until proven otherwise. If the murmur is systolic and louder than 2/6, then it should be investigated. If there is persistent splitting of S-2 or persistent jugular venous distension, then further cardiac assessment is required. Investigations should include an echocardiogram, an electrocardiogram, and possibly a chest X-ray. If an abnormality is found, an appropriate referral should be made. If the woman is hypertensive (has a raised systolic or diastolic blood pressure), this should be investigated and treatment instituted along with an appropriate referral. If a woman reports a new history of palpitations, after excluding thyroid disease, ambulatory cardiac telemetry (Holter monitor) should be considered to exclude episodes of abnormal heart rhythm (ventricular tachycardia/supraventricular tachycardia). Additionally, echocardiography may need to be performed. Other additional cardiac investigations such as magnetic resonance imaging (MRI) may sometimes need to be undertaken in pregnancy. Understandably, there is often concern expressed about the safety of these investigations in pregnancy by not only the mother but also other physicians. MRI, in particular, is considered to be safe beyond the first trimester, although gadolinium contrast agent (employed to demonstrate fibrosis) should be avoided unless absolutely essential because it crosses the placenta and its effects on the fetus are not known (it is nephrotoxic in adults and can lead to gadolinium-induced nephrogenic systemic fibrosis).[17]

Where should the woman be managed? The first Confidential Enquiry into Maternal Deaths for the period 1952–1954 recommended that “all patients known or suspected to be suffering from heart disease should be referred for their care in pregnancy to a hospital where they can receive the necessary supervision,” and this recommendation remains valid today.[18] If a woman has a known cardiac disorder, the obstetrician needs to decide whether it is appropriate for her to remain under local care or whether she would be best served by a referral to a tertiary unit which can provide joint obstetric/cardiac care at a specialist level (“maternal cardiac center”). If there is obstetric uncertainty, then it is appropriate to refer the woman to such a center for advice. The advice from specialists may simply

indicate how the woman could best be managed locally by providing a clear pregnancy care and delivery plan.

Assessment of risk In order to decide where a woman should be cared for, the obstetrician needs to make a risk assessment. As discussed elsewhere, “risk stratification is best accomplished before conception,”[19] but in practice this does not always happen. Siu and Colman set out four areas that should be considered in an assessment of maternal cardiac risk [20]: 1. The underlying cardiac lesion 2. Maternal functional status 3. The need for further palliative or corrective surgery 4. Additional associated risk factors.

The underlying cardiac lesion Women with cardiac disease can be divided into those with trivial conditions that are unlikely to have an effect on either her or the fetus, and those with moderate or severe lesions that might have an effect on her, the fetus, or both.

Trivial and low-risk cardiac lesions Trivial or insignificant lesions include small ventricular septal defects (VSDs), repaired VSDs with normal cardiac function, and trivial valve prolapse (commonly mitral), which affects twice as many women as men.[21] Cardiac lesions posing a low risk to the mother (i.e. 1% but generally 10%). These major risk lesions include critical left-side obstruction, left ventricular failure, and pulmonary hypertension including Eisenmenger syndrome.

NYHA classification of cardiac function Further risk stratification can be achieved using the NYHA system, which has four classes (see Appendix A): • Class I—uncompromised (no limitation of physical activity) • Class II—slight limitation of physical activity • Class III—marked limitation of physical activity • Class IV—severely compromised. Siu et al. demonstrated a correlation between maternal outcome and NYHA functional status, with those women classified with NYHA higher than II having a significantly higher chance of a poor outcome.[19] Poor maternal functional class was also predictive of a poor fetal outcome.

Additional associated risk factors The primary associated risk factors are related to the use of medication, particularly warfarin and angiotensin-converting enzyme (ACE) inhibitors. These both carry a significant risk to the fetus. Warfarin in particular presents a therapeutic dilemma, predominantly in the presence of an artificial heart valve. In this situation, the woman and her obstetrician need to make a stark choice between therapeutic regimens that favor the fetus (a change to other forms of anticoagulation, such as low-molecular-weight heparin [LMWH] and aspirin) but carry an increased risk to the mother, and those that favor the mother (e.g. remaining on warfarin) but represent a significant risk to the fetus. This is covered in detail in Chapter 7.

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What should the woman be told? Having defined the mother’s underlying cardiac lesion and established the pertinent risks associated with her lesion in pregnancy, the obstetrician is in a position to determine where the woman will receive the most appropriate management and care. Wherever this might be, the primary duty of the obstetrician at the first antenatal clinic attendance is to explain the risks inherent in her choice to remain pregnant. This discussion should also include how her cardiac condition might affect her fetus. The 2002 report by the British Cardiac Society (BCS) on the needs of adolescents and adults with CHD in the UK expressed the view that poor advice before pregnancy often leads to poor choices and consequent morbidity and mortality from heart disease in pregnancy.[24] The obstetrician thus needs to discover whether or not the woman has had prepregnancy counseling and, if she has, what she has remembered and, more importantly, what she has understood. If she has not had counseling, the woman needs to be properly counseled. The issues that need to be covered are set out in Table 4.1 of the BCS report.[24] It is important that this counseling is done by an expert, and it must include both the risk of maternal mortality and morbidity and the chance of a successful outcome for the pregnancy. The 2011 European Society of Cardiology guideline outlines the different scoring systems for risk stratification and gives a worked example.[25] Counseling should also include the risk of the fetus inheriting CHD and issues of child care should the mother die or become too ill to care for the child. Part of this counseling may also need to include a discussion about the possibility of terminating the pregnancy if the health of the mother deteriorates rapidly as a consequence of the pregnancy. The standard for such counseling should be very high, in terms of both content and communication. The obstetrician needs to be sure that the woman has received the information that she needs to make a valid choice. In the event of an adverse outcome, the quality of the counseling given may be subject to legal challenge. This is particularly important when the woman has a condition such as pulmonary hypertension, a dilated aortopathy, or a failing heart (systemic ventricular dysfunction), all of which carry a high risk of maternal mortality. Following counseling, the choices the woman makes are ones that she, her family, and her medical team will have to manage whatever the outcome.

Chapter 4: Antenatal care of women with cardiac disease: An obstetric perspective

Planning antenatal care Having established a diagnosis and counseled the woman appropriately, the next task for the obstetrician and the multidisciplinary team (MDT) is to plan the antenatal care and determine how it should be delivered. The obstetrician has the role of “care coordinator” and has overall responsibility for both the mother and her fetus. Obstetricians do not have the particular expertise of the cardiologist, the anesthetist, or the midwife but they do have a particular understanding both of the physiological changes to the woman brought about by her pregnancy and of fetal growth and well-being. Obstetricians are also accustomed to making judgments involving the well-being of both the mother and her fetus and to helping decide when and how a baby should be delivered. The purpose of antenatal care is to ensure the continued well-being of both the mother and her fetus and to manage any deviation from the norm. Ideally, the same team should review the woman at each of her antenatal visits in order to provide continuity of care. This level of personalized care increases the chance that the team will recognize subtle changes in the woman’s status. Prompt intervention before major cardiac decompensation ensues can prevent significant problems, as can the early diagnosis and management of preeclampsia. Scrupulous attention to detail is therefore paramount when managing women with cardiac disease in pregnancy.

The multidisciplinary team and antenatal care The MDT team should include a cardiologist, an anesthetist, a specialist midwife, an obstetrician, a fetal medicine specialist, a pediatrician, and trainees. Each pregnant woman’s case should be considered in detail by the whole team early in the pregnancy and a careful plan should be made for the mother’s antenatal care and delivery. The plan should be recorded and should include such basic things as the frequency of appointments, the number and frequency of investigations of the mother, and the number and frequency of investigations of the fetus. In view of the large number of medical staff working in any particular unit and the fact that they will not all be familiar with cardiovascular disease in pregnancy, the record should be easy to interpret and should consider foreseeable contingencies such as labor. The record should also act as an aid to the team, reminding them to perform routine tasks

(which are easy to forget) at each antenatal visit. These tasks should usually include [26]: • measuring the pulse rate and blood pressure • assessing the heart rhythm • auscultating the heart sounds • listening to the lung bases • checking the urine for protein (mandatory if the blood pressure is raised) • assessing fetal growth. They should also record all medications the woman is on and any alterations to the dose of these medications. An example of an integrated antenatal care pathway and record for women with heart disease is shown in Appendix B.

The fetus and fetal surveillance The primary risks to the fetus are inheriting a congenital cardiac disorder, the potential for harm as a result of maternal medication, fetal growth restriction (FGR), which may be secondary to compromised maternal cardiac output, and preterm birth (often iatrogenic). Overall, in women with coexisting heart disease, the rate of preterm delivery is increased (16% overall in one study,[27] with rates as high as 65% in high-risk disease such as Eisenmenger syndrome). This results from a combination of higher rates of spontaneous preterm rupture of membranes and obstetric intervention before 37 weeks of gestation. In addition, women with cyanotic heart disease, dilated cardiomyopathy and a reduced ejection fraction, or hypertrophic cardiomyopathy and severe restrictive physiology have fetuses at a particularly high risk of FGR. Significant mitral stenosis may also lead to FGR because of the effect of stenosis on reduced cardiac output but perhaps also because medical treatment classically includes beta-blockade. Fetuses of women with coarctation of the aorta, for example, may be at risk of FGR at least in part because a common medical treatment is beta-blockade. In the presence of good hemodynamics, however, and for women in NYHA classes I and II, fetal outcome is generally good. All women should be offered nuchal translucency screening in early pregnancy.[28] While this screening test was developed for the assessment of the risk of Down syndrome, it has also been shown to have an association with CHD. Fetal CHD is associated with an almost 60% incidence of increased nuchal thickness.[29] Early fetal echocardiography at between 14 and 16 weeks of gestation is available at some centers.

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This can detect severe CHD, but detection of less severe disorders requires additional echocardiography when the fetus is larger and easier to image. This is generally done both at the 20-week anomaly scan and at the standard fetal echocardiogram, usually performed at between 18 and 22  weeks. The fetal echocardiogram should be performed by a trained fetal cardiologist. Providing there are no specific risk factors for growth restriction, such as cyanotic heart disease, significant hypertension, or beta-blockade, the routine measurement of symphysis-fundal height for the assessment of fetal growth is probably sufficient. Where there is serious concern that the fetus might be growth restricted, serial ultrasound is indicated.

Frequency of visits and admission to hospital The care of women with cardiac lesions during pregnancy is not cheap. This is currently a particular problem for maternity units within the UK National Health Service. The introduction of the “tariff system,” which pays hospitals for the provision of maternity care, is likely to have an adverse effect on specialist services because it fails to compensate for the full expense of caring for a pregnant woman with heart disease. Specialist care for women at high risk during their pregnancy is expensive because of the cost of repeated antenatal checks, prolonged admissions to hospital, and the need for a MDT. Antenatal appointments need to be frequent and senior members of the MDT should provide the antenatal care. At the Chelsea and Westminster/Royal Brompton obstetric clinic, visits are often booked every fortnight until 24 weeks of gestation, and weekly thereafter. The threshold for admission should be low and it is not uncommon to admit women to the unit early in the third trimester for both medical and organizational reasons (many women live a long way from their tertiary referral unit).

Postnatal care The postpartum period remains a period of high risk for women with cardiac disease. Cardiac output is at its highest just after delivery and the obstetrician needs to be alert to complications such as the rapid development of heart failure or aortic dissection. Furthermore, there is a significant increase in the risk of thrombosis in the puerperium. As part of delivery planning, there should be careful consideration of the appropriate postpartum

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care, such as elective admission to an obstetric high dependency unit with its continued monitoring and multidisciplinary management.

References 1. Stout K. Pregnancy in women with congenital heart disease: The importance of evaluation and counseling. Heart 2005;91:713–14. 2. National Health Service. Adult Congenital Heart Disease (A commissioning guide for services for young people and Grown Ups with Congenital Heart Disease (GUCH) London: Dept of Health; 2006. 3. Cantwell R, Clutton-Brock T, Cooper G. Saving Mothers’ Lives: Reviewing maternal deaths to make motherhood safer 2006–2008. The Eighth Report of the Confidential Enquiries into Maternal Deaths in the United Kingdom. BJOG 2011;118:1–203. 4. Hunter S, Robson SC. Adaptation of the maternal heart in pregnancy. Br Heart J 1992;68:540–3. 5. Whittaker PG, Macphail S, Lind T. Serial hematologic changes and pregnancy outcome. Obstet Gynecol 1996;88:33–9. 6. Pritchard JA. Changes in the blood volume during pregnancy and delivery. Anesthesiology 1965;26:393–9. 7. Chesley LC. Plasma and red cell volumes during pregnancy. Am J Obstet Gynecol 1972;112:440–50. 8. Robson SC, Hunter S, Boys RJ, Dunlop W. Serial changes in pulmonary haemodynamics during human pregnancy: A non-invasive study using Doppler echocardiography. Clin Sci (Lond) 1991;80:113–17. 9. Robson SC, Dunlop W, Boys RJ, Hunter S. Cardiac output during labour. Br Med J (Clin Res Ed) 1987;295:1169–72. 10. Robson SC, Hunter S, Moore M, Dunlop W. Haemodynamic changes during the puerperium: A Doppler and M-mode echocardiographic study. Br J Obstet Gynaecol 1987;94:1028–39. 11. Kenny A, Shapiro LM. Sudden cardiac death in athletes. Br Med Bull 1992;48:534–45. 12. Huisman CM, Zwart JJ, Roos-Hesselink JW, Duvekot JJ, van Roosmalen J. Incidence and predictors of maternal cardiovascular mortality and severe morbidity in The Netherlands: A prospective cohort study. PLoS One 2013;8(2):e56494. 13. Burrow G, Duffy T, Copel J, eds. Medical Complications During Pregnancy, 6th edn. Philadelphia: Elsevier Saunders; 2004. 14. British Hypertension Society. [http://www.bhsoc.org/ resources/bhs-dvd/] [accessed September 22, 2015]

Chapter 4: Antenatal care of women with cardiac disease: An obstetric perspective

15. Beevers G, Lip GY, O’Brien E. ABC of hypertension. Blood pressure measurement. Part I –sphygmomanometry: Factors common to all techniques. BMJ 2001;323:805. 16. British Hypertension Society. Video tutorial. [www. abdn.ac.uk/medical/bhs/tutorial/tutorial.htm]. [Accessed September 21, 2015] 17. Kilner PJ, Geva T, Kaemmerer H, Trindade PT, Schwitter J, Webb GD. Recommendations for cardiovascular magnetic resonance in adults with congenital heart disease from the respective working groups of the European Society of Cardiology. Eur Heart J 2010;31:794–805. 18. Lewis, G, ed. Why Mothers Die 2000–2002: The Sixth Report of Confidential Enquiries into Maternal Deaths in the United Kingdom. London: RCOG Press; 2004. 19. Siu SC, Sermer M, Colman JM, et al. Cardiac Disease in Pregnancy (CARPREG) Investigators. Prospective multicenter study of pregnancy outcomes in women with heart disease. Circulation 2001;104:515–21. 20. Siu SC, Colman JM. Heart disease and pregnancy. Heart 2001;85:710–15. 21. Freed LA, Levy D, Levine RA, et al. Prevalence and clinical outcome of mitral-valve prolapse. N Engl J Med 1999;341(1):1–7. 22. Head CE, Thorne SA. Congenital heart disease in pregnancy. Postgrad Med J 2005;81(955):292–8. 23. RCOG Heart Disease and Pregnancy Study Group. Cardiac Disease and Pregnancy (Good Practice No. 13). [https://www.rcog.org.uk/

en/guidelines-research-services/guidelines/ good-practice-13/] [Accessed September 21, 2015] 24. Report of the British Cardiac Society Working Party. Grown-up congenital heart (GUCH) disease: Current needs and provision of service for adolescents and adults with congenital heart disease in the UK. Heart 2002;88 (Suppl 1):11–14. 25. European Society of Gynecology (ESG), Association for European Paediatric Cardiology (AEPC), German Society for Gender Medicine (DGesGM), et al. ESC Guidelines on the management of cardiovascular diseases during pregnancy: The Task Force on the Management of Cardiovascular Diseases during Pregnancy of the European Society of Cardiology (ESC). Eur Heart J 2011;32:3147–97. 26. Steer PJ. Pregnancy and contraception. In: Gatzoulis M, Swan L, Therrien J, Pantley G, eds. Adult Congenital Heart Disease. London: Blackwell; 2005. pp. 16–36. 27. Drenthen W, Boersma E, Balci A, et al. Predictors of pregnancy complications in women with congenital heart disease. Eur Heart J 2010;31(17):2142–32. 28. National Collaborating Centre for Women’s and Children’s Health. Antenatal Care: Routine Care for the Healthy Pregnant Woman. NICE Clinical Guideline. London: RCOG Press; 2008. [www.nice.org.uk/ guidance/CG62]. [Accessed September 21, 2015] 29. Makrydimas G, Sortidiadis A, Huggon I, et al. Nuchal translucency and fetal cardiac defects: A pooled analysis of major fetal echocardiography centers. AJOG 2005;192 (1):89–95.

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Section 2 Chapter

5

Antenatal Care: General Considerations

Antenatal care of women with cardiac disease: A cardiac perspective Fiona Walker

Practical practice points 1. Antenatal care plans should be based on careful assessment by the multidisciplinary team. 2. Stratification using the World Health Organization criteria is helpful for determining the level of care required. 3. The key to high quality care is good communication between all members of the team. 4. Cardiac clinical nurse specialists can enhance this communication and play a useful coordinating role.

Introduction Depending on the obstetric population and the profile of referral, 0.5–3.0% of women have a form of heart disease that is already known before or diagnosed during pregnancy. There is usually a favorable maternal and fetal outcome, but it must be borne in mind that heart disease is now the single leading cause of maternal death in the UK.[1] Better maternity care over the years has improved outcomes, but the fact that cardiac disease remains a major contributor to maternal mortality statistics is a cause of concern. It is also noteworthy that the majority of cardiac deaths are in those with undiagnosed heart disease and that substandard care is identified as causal in approximately 50%. This highlights the need for a greater awareness and recognition of the problem by medical professionals, as well as better organization of antenatal care for women with heart disease overall. In the UK, maternal mortality data are collected by the Confidential Enquiry into Maternal and Child Health.[1] There is, however, no national initiative or database that records the overall prevalence of maternal heart disease across the UK, nor are there any

national guidelines for the management of women with heart disease in pregnancy, apart from a “good practice guide” (number 13)  published by the Royal College of Obstetricians and Gynaecologists on their website (https://www.rcog.org.uk/en/guidelinesresearch-services/guidelines/good-practice-13/). How­ ever, in 2011, the European Society of Cardiology (ESC) produced guidelines for the management of pregnancy in heart disease.[2] They provide a useful reference text, although it must be borne in mind that guidelines on the whole tend to précis and generalize, whereas in clinical practice problems are often multiple and patient specific. Moreover, heart disease in pregnancy is a truly multidisciplinary specialty, with clinical interdependencies that are particularly difficult to incorporate into lesion-specific guidelines. It is clear that a model for the organization and delivery of antenatal care for these women needs to be adopted nationally. The consensus view following the 51st Royal College of Obstetricians and Gynaecologists (RCOG) Study Group on Heart Disease in Pregnancy was that there was a need for specialist high-risk obstetric teams and a network of recognized care providers. Changes to models of care delivery, however, are often slow to evolve from such recommendations and these networks have yet to become a reality in UK practice. There is, however, a new initiative from UK National Health Service (NHS) England that may expedite this process. They are currently reviewing services for children and adults with congenital heart disease (CHD) have completed the consultation phase with implementation likely in early 2016.[3] These standards include recommendations for pregnancy care, which generally concur with the RCOG study group consensus view. Although the main focus on these standards relates to services for patients with CHD, if they are adopted and implemented they will be

Heart Disease and Pregnancy, 2nd edn. ed. Philip J. Steer and Michael A. Gatzoulis. Published by Cambridge University Press. © Cambridge University Press 2016.

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Chapter 5: Antenatal care of women with cardiac disease: A cardiac perspective

applicable to all women with heart disease. With NHS England as the main driver of this process, it is likely that these care models will be more readily adopted, thanks to their alignment with funding streams. In this chapter, I will discuss the current and evolving spectrum of maternal heart disease based on my own clinical practice and suggest strategies for providing safe, high quality care for these women. I will also draw on 2011 Centre for Maternal and Child Enquiries (CMACE) recommendations, the new NHS England standards, and ESC guidelines. (Editors’ note: CMACE was until 2011 responsible for the Confidential Enquiry into Maternal Mortality in the UK. Owing to changes in European procurement legislation, the enquiry was put out to tender and a reduced level contract was awarded to the MBRRACE-UK collaboration (“Mothers and Babies: Reducing Risk through Audits and Confidential Enquiries across the UK”) and CMACE closed on March 31, 2011. Because of the reduced funding and the requirement to produce annual reports, a further assessment of maternal deaths associated with cardiac disease will not now be produced until 2016.)

The spectrum of maternal heart disease There has been a significant change in the nature of maternal heart disease over the last 40  years. Fifty years ago, rheumatic disease was highly prevalent, found in up to 1% of young pregnant women, but it is now uncommon and is largely confined to areas in which there are immigrant communities. This means that some perceive heart disease in pregnancy to be a vanishing problem, but this is of course not the case. If anything, it will be encountered with increasing frequency and with disease of greater complexity thanks to the improved survival of young patients with all forms of heart disease. CHD is now more common in pregnancy than any other heart disease. This is thanks to improvements in infant cardiac surgery and pediatric cardiology care over the same period. About 85–90% of children born with CHD now survive to adulthood and about half are women of reproductive age. For these patients, “total correction” or “cure” of CHD is the exception. The majority are palliated, with an ongoing requirement for long-term specialist follow-up. Many lesions surgically repaired in infancy can recur or deteriorate in adulthood. Some have residual lesions following their primary repair, which although well tolerated in childhood can lead to problems in adulthood,

with a need for redo surgery or intervention. Some may have simply “outgrown” their initial repairs and need larger conduits or valves implanted. Although most should have life-long specialist follow-up, many are lost to follow-up, particularly during transition between pediatric and adult cardiology services. They may only re-present to hospital services when pregnant; in this case, urgent cardiac review and assessment are needed. Women with CHD represent a unique patient population reaching childbearing age. They have a wide variety of cardiac lesions, with any combination of valvar heart disease (regurgitation, stenosis, mechanical), myocardial disease (hypertrophy, dilatation, dysfunction, single ventricle), lung problems (pulmonary hypertension [PH], restrictive ventilatory defects, single lung), cyanosis, and/or arrhythmias. Accurate prevalence data are lacking but CHD occurs in almost 1% of live born babies and is the commonest birth defect, so they represent a large patient population that may come to require antenatal care. Another important patient group I see in increasing numbers are those with inherited heart disease, including the cardiomyopathies (hypertrophic, dilated, arrhythmogenic right ventricular dysplasia, left ventricular noncompaction), Marfan syndrome, and inherited arrhythmias. There is now a greater awareness and better diagnosis of the inherited cardiomyopathies, as well as improved genetic screening. This, coupled with better medical treatment and risk stratification for sudden cardiac death, has significantly improved the prognosis and survival of this patient group. These women also pose a management challenge during pregnancy, and may have any combination of myocardial dysfunction, left ventricular outflow tract obstruction, atrioventricular valve regurgitation, and/or atrial or ventricular dysrhythmias. They will often have devices in situ for the treatment of arrhythmias (implantable cardiac defibrillators) and/or heart failure (biventricular pacemakers), which adds another layer of complexity to their management. For women with Marfan syndrome, familial screening has improved prognosis. Even outside the context of pregnancy, those with aortic root dilatation (>50 mm in diameter) are operated on electively to prevent acute aortic dissection. There is, however, a risk that most cardiologists seem to be less familiar with:  50% of all acute aortic dissections in women under 40 years of age occur in pregnancy. Pregnancy therefore represents a high risk even in the absence of aortic root dilatation.[4,5]

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Section 2: Antenatal Care: General Considerations

Other conditions I see with increasing frequency are women with impaired left ventricular function and women with coronary heart disease. Those with impaired ventricles are made up mainly of patients with peripartum cardiomyopathy (PPCM), familial dilated cardiomyopathy, and chemotherapy cardiomyopathy. For women with PPCM, outcome in a subsequent pregnancy can be unpredictable and the risks high, especially if left ventricular function has not normalized. Similarly, for survivors of childhood and teenage cancer who have impaired left ventricular function following the use of cytotoxic therapy, outcome can be unpredictable, with a possibility that left ventricular function can deteriorate during pregnancy. The fact that ischemic heart disease is now one of the main causes of maternal cardiac death reflects the startling growth of obesity and poor diets in the general population in recent years, and cigarette smoking (although fortunately the incidence of the latter is now in decline). Symptoms of chest pain and or breathlessness in a woman of childbearing age, or during pregnancy, can therefore no longer be confidently diagnosed as “noncardiac,” unless appropriately considered and investigated. Along with these changing trends in the prevalence and complexity of maternal heart disease, patient expectations have increased. Many patients believe that modern medicine can “cure all,” and even if complications occur they would rarely consider that treatment might be unsuccessful or that death is a possibility. Risk assessment in this area is, however, not an exact science and there is much unpredictability and

uncertainty. Providing a wholly accurate prediction of the outcome or a percentage probability of complications is therefore impracticable. Despite this, as clinicians we must do our best to counsel, organize, and coordinate care to provide best outcomes for mother and child with the resources available and, although precise estimates of risk are not possible, we must give women and their families our best assessment. For medicolegal purposes, giving at least an approximate assessment of risk as a percentage is important.

Organization of antenatal care A useful template for organizing antenatal care for women with heart disease can be derived by modifying the current pregnancy recommendations of the ESC. [3] Cardiac lesions are categorized by modified World Health Organization (WHO) criteria from I  (undetectable increased risk of death/mild increase morbidity) to IV (extremely high risk of death/severe risk of morbidity; Figure 5.1). Patients are then triaged into an appropriate care setting following review by a specialist high-risk obstetric multidisciplinary team (MDT). The MDT and the specialist pregnancy unit should fulfill specific criteria for a minimum standard of care provision (Figure  5.2). In our center, the core team includes the following professionals:  an obstetrician with experience in high-risk obstetrics, a cardiologist experienced in maternal heart disease with an in-depth knowledge of congenital heart disease, an obstetric anesthetist with cardiac experience, an intensivist and level III intensive care facilities, a neonatologist and a

WHO risk classification

Description

I: No detectable increased risk of death or nil/mild increased morbidity

Repaired conditions without residua, small VSD, isolated PFO/ASD, repaired anomalous pulmonary venous drainage, pulmonary stenosis

II: Small increased risk of mortality or moderate increased morbidity

Hypertrophic cardiomyopathy, mild LV dysfunction, Marfan syndrome with normal aorta, bicuspid aortic valve aorta 45 mm, Marfan aortopathy aorta >40 mm

IV: Extremely high risk or of mortality or severe morbidity—pregnancy contraindicated

Pulmonary hypertension, severe LV dysfunction EF 45 mm, bicuspid aortopathy with aorta >50 mm, severe coarctation of the aorta

Figure 5.1  WHO risk classification. ASD = atrial septal defect; AV = atrioventricular; EF = ejection fraction; LV, left ventricle; PFO = patent foramen ovale; VSD = ventricular septal defect.

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Chapter 5: Antenatal care of women with cardiac disease: A cardiac perspective

1. 2. 3. 4. 5. 6. 7. 8.

9. 10. 11. 12. 13. 14. 15.

The unit must be located in an adult medical environment. Multidisciplinary specialty provision should be available. There must be an association with strong pediatric cardiology groups with defined care pathways for the appropriate transfer of patients to the adult service when deemed appropriate. The specialist unit should serve a population of approximately 5-10 million people and it should function within the local medical community. Local cardiologists and primary care physicians should be encouraged to establish a referral relationship with the specialist unit. Specialist units should provide timely telephone advice, informal consultation, rapid consultant referrals as well as collaboration in patient follow-up. The specialist unit should include cardiologist(s) with training in management of grown-ups with congenital heart disease in a collaborative team including cardiac surgeons, anesthetists and intensivists. Specialist consultants should be familiar with echocardiography (including transesophageal echocardiography) and diagnostic cardiac catheterization and one consultant per center should have experience in interventional catheterization. Specialist units should have access to an electrophysiologist with expertise in arrhythmia management in congenital heart disease, pacemaker insertion, ablation and defibrillator implantation. Specialist imaging including MRI and CT should be available. The specialist unit should have close links with other specialist departments and, in particular, the provision of a joint service with obstetrics to manage high-risk pregnancies. Access to a cardiac pathologist with an interest in congenital cardiac malformations is also highly desirable. A minimum of two congenital heart surgeons (often shared with pediatric cardiology units) should be available. Anesthetists, intensive care and surgical teams with interest in congenital heart disease is desirable. The specialist unit should have an association with a transplant center.

level III neonatal intensive care unit, a fetal–maternal medicine specialist with expertise in fetal echocardiography, a hematologist with experience in maternal medicine, a midwife with general/intensive-care training and experience, and a cardiac clinical nurse specialist. A cardiac clinical nurse specialist and link midwife can together act as intermediaries between cardiology and obstetrics. Together, they can develop care pathways and provide clear guidance to nursing and midwifery staff in each of their areas. In the event that a mother has to deliver in the cardiac unit, this co-worker relationship across the two specialties is invaluable. Despite preconception counseling and a prepregnancy investigation, early delivery might be needed for maternal health reasons. Obstetric complications, such as twin pregnancy, preeclampsia, or the development of unheralded arrhythmias may exacerbate minor hemodynamic problems, leading to clinical deterioration even in the setting of noncomplex heart disease. Good neonatal intensive care unit services

Figure 5.2  Criteria for a specialist congenital heart disease unit.

permit timely delivery, thus ensuring maternal health is prioritized while fetal welfare is not significantly compromised. Other services that should be in close proximity and readily accessible, with defined referral protocols, include cardiac surgery, a coronary interventionist, an experienced structural interventionist, and a transplant center that offers mechanical circulatory support. These specialist services provide a “comfort zone” when in the face of unexpected and or serious complications. Not all women will have remained under specialist follow-up for their cardiac disease, and therefore some re-present in pregnancy with significant disease that needs urgent treatment, for example aortic valvuloplasty for aortic stenosis. Cardiac surgery, although rarely needed, can be life-saving if there has been an acute catastrophic event such as mechanical valve thrombosis or aortic dissection, while ventricular assist devices are life-saving for those with severe impairment of ventricular function and hemodynamic collapse.

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Section 2: Antenatal Care: General Considerations

Recommendations for organization of antenatal care All pregnant women with heart disease should be referred to a specialist high-risk obstetric service with a MDT as defined above. They should have at least one specialist cardiology and obstetric review, with clinical assessment and transthoracic echocardiogram. Thereafter, based on the risk assessment (WHO I–IV), they can be stratified to the following antenatal care pathways:

Level I care—exclusive care by a specialist high-risk antenatal service Level II care—shared care; regular specialist cardiology review and local obstetric care, with clear lines of communication between specialists Level III care—local care; local cardiology review and local obstetric care, with clearly defined lines of communication between specialists. Following each review, a report should be generated that includes diagnosis, a heart diagram, a clinical summary, recent investigations, and the anticipated

Obstetric cardiac case Name: LS D.O.B.: G2P1 EDD: 30/07/2004 Diagnosis: Transposition of the great vessels. Mustard repair 1975. LV–PA conduit for LVOTO 1984. Replacement conduit 1993. DDDR pacemaker for tachy–brady syndrome 1998.

Prepregnancy status: Medications: Clinical examination findings: Current status @ x/40: Past obstetric history: Recent investigations: TTE/ETT/MRI/Angio Hemodynamic issues: Delivery plan: Labor and delivery: Elective CS planned for 38/40 with epidural anaesthesia (previous CS). Endocarditis prophylaxis to be given at induction. Drugs to be available on labor ward: Hemodynamic monitoring and intrapartum care: Postpartum care and monitoring: Discharge plan and follow up: Plan provided by:

40

Figure 5.3  Template for high-risk cardiac obstetric cases.

Chapter 5: Antenatal care of women with cardiac disease: A cardiac perspective

Level l Exclusive care in a specialist unit with a multidisciplinary team

Repairs with conduits, Fontan, Marfan syndrome, Ebstein anomaly, pulmonary atresia, Eisenmenger syndrome, repaired complete transposition of great arteries (arterial switch or atrial switch), congenitally corrected transposition of great arteries, pulmonary hypertension, cyanotic congenital heart disease, native coarctation of the aorta, aortic stenosis, tetralogy of Fallot with pulmonary regurgitation (moderate), ventricular septal defect/aortic regurgitation, mechanical valves, hypertrophic cardiomyopathy, dilated cardiomyopathy

Figure 5.4  Hierarchy of care for pregnant women with congenital heart disease.

Toronto score ≥ 1 Level lI Shared care between a specialist cardiologist and a local obstetric team

Coarctation of the aorta (repaired), atrioventricular septal defect, aortic stenosis, pulmonary stenosis/pulmonary regurgitation (mild), tetralogy of Fallot with minimal residua, ventricular septal defect and aortic regurgitation Toronto score 0

Level lI Shared care between a general adult cardiology unit and a local obstetric team

Repaired patent ductus arteriosus, mild pulmonary stenosis, small ventricular septal defect, repaired atrial septal defect Toronto score 0

hemodynamic impact of pregnancy. In the later stages of pregnancy, the report should also provide guidance on delivery planning (monitoring requirements, drugs to be available on labor ward, requirements for endocarditis prophylaxis, and peri-/postpartum care requirements). A copy should be given to the patient and all medical personnel involved both within the specialist center and in the local unit. A template for such a report is shown in Figure 5.3. This care model needs to be flexible to the needs of the patient, and easily transferable between centers so that if there are unexpected complications or if any of the care providers do not feel comfortable, then the patient can be moved to a higher level of care provision. An overall schema for this pattern of care is shown in Figure 5.4. At present, most of the specialist high-risk pregnancy services in the UK have developed allied to units that provide specialist care to adults with congenital heart disease. These units and their pregnancy services often form the “hub” of an ever-increasing number of “spoke” centers. This model of care will evolve over time, eventually forming a regional network of recognized care providers. At present, cardiology and maternal medicine trainees are expected to gain knowledge and exposure

to heart disease in pregnancy, and many colleges recognize the importance of this subject with dedicated training days and conferences. With these improvements in education and awareness, the hub and spoke model will eventually map out across geographical sectors, allowing the appropriate level of care for all women with heart disease. On a practical level, there are several possible ways to organize service. Each specialist unit should have input to the care plan by the core physicians on a regular basis, with patients reviewed by all members of the MDT either simultaneously or individually. At University College London Hospital, complex cases are discussed at a multidisciplinary case conference. The focus is on the patient care pathway, delivery planning, and staff education. A final delivery plan is formulated at this meeting and copied to the electronic patient record, the family doctor, and all health care professionals involved in care. The essence of a good high-risk antenatal care team is good communication and teamwork. All members must fulfill their individual commitments and responsibilities while they communicate and function as a single unit. Good communication is also key to sharing care with spoke centers, with concerns and queries responded to promptly.

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Section 2: Antenatal Care: General Considerations

The University College London Hospital experience Over 1400 successful pregnancies in women with heart disease have now been cared for by the team. Each year the number of referrals increases, and there are now around 180–200 deliveries/year in women with heart disease. The majority of women (~60%) have moderate or complex heart disease (WHO II–IV) and 40% have simple heart disease (WHO I–II); 95% of pregnancies have had no cardiovascular morbidity. Of the 5% of pregnancies with cardiovascular complications, most women were advised that complications were likely when counseled prior to pregnancy, and unanticipated complications have been very rare. Sadly, there were two maternal deaths: one acute aortic dissection in a patient with a bicuspid aortopathy (aortic diameter of 50 mm) with a surgically modified aorta; and one obstetric death from sepsis in a patient with congenital complete heart block (not paced).

Current limitations and solutions Thanks to specialist cardiac units serving patients with congenital heart disease and high-risk maternity services experienced in managing women with heart disease, the so-called “hub” centers are accessible in most

42

regions the UK. There are still, however, too few spoke centers, and a national formalized network of care providers is not well developed, representing the next challenge.

References 1. www.npeu.ox.ac.uk/mbrrace-uk accessed December 1, 2015. 2. European Society of Gynecology (ESG), Association for European Paediatric Cardiology (AEPC), German Society for Gender Medicine (DGesGM), et al. ESC Guidelines on the management of cardiovascular diseases during pregnancy: The Task Force on the Management of Cardiovascular Diseases during Pregnancy of the European Society of Cardiology (ESC). Eur Heart J 2011;32:3147–97. 3. NHS England. Proposed congenital heart disease standards and service specifications. A consultation. September 2014. www.england.nhs.uk/qual-clin-lead/ chd/consultation/ [Accessed September 21, 2015] 4. Meijboom LJ, Vos FE, Timmermans J, Boers GH, Zwinderman AH, Mulder BJ. Pregnancy and aortic root growth in the Marfan syndrome: A prospective study. Eur Heart J 2005;26:914–20. 5. Rossiter JP, Repke JT, Morales AJ, Murphy EA, Pyeritz RE. A prospective longitudinal evaluation of pregnancy in the Marfan syndrome. Am J Obstet Gynecol 1995;173:1599–606.

Section 2 Chapter

6

Antenatal Care: General Considerations

Cardiac monitoring during pregnancy Henryk Kafka, Sonya V. Babu-Narayan, and Wei Li

Practical practice points 1. Echocardiography is central to the management of pregnant women with heart disease. For all cases, the following assessments should be made initially and then repeated as necessary: (a) ventricular size and function (b) valvar abnormality and function (c) estimation of cardiac pressures, in particular, pulmonary artery pressure (d) aortic dimensions. 2. Measurement of ventricular function is particularly important in relation to cardiomyopathy. 3. Serial measurement of aortic root dimensions is important in all women with aortopathy. 4. Magnetic resonance imaging is generally safe during pregnancy. 5. Computed tomography scans, nuclear imaging, and cardiac catheterization should be reserved for cases of suspected pulmonary embolism, aortic dissection, severe mitral stenosis, or suspected myocardial infarction.

Introduction To formulate the best plan for optimal cardiac monitoring for any pregnant patient with heart disease, it is necessary to understand the specific type of heart disease, as well as the severity of that heart disease in the patient, and then use that information to develop a risk profile. Once the risk profile has been established, the type of monitoring and its frequency can be determined. It needs to be emphasized that neither the cardiologist nor the obstetrician alone has the training,

experience, or expertise to deal with all aspects of the pregnancy in such patients. A collaborative team approach is thus necessary.[1,2]

Initial assessment of the patient Pregnant women who are referred to the cardiologist with heart disease will fall into one of four categories, and this will have a bearing on the scope and pace of the initial assessment. 1. Previously diagnosed heart disease—well documented with ongoing follow-up 2. Previously diagnosed heart disease—lost to follow-up 3. Previously undiagnosed heart disease that is chronic—for example, mitral stenosis 4. Previously undiagnosed heart disease that is acute—for example, myocardial infarction. The approach for each of these types of patients differs. Ideally, a woman with previously diagnosed heart disease would already have had preconception counseling (Chapter 1). Since the majority of teenage pregnancies are unplanned, it would be ideal if much of this counseling had already occurred in adolescence. In practice, such counseling has often not taken place and the patient arrives pregnant and unaware of the severity of her cardiac situation and of the inherent risks of the pregnancy. Therefore, a complete initial assessment is necessary not only for the cardiologist and obstetrician but also to ensure that the patient understands her situation and the situation of her unborn child. For some women, pregnancy may be the first occasion in which they have a comprehensive medical assessment and it may be the first time a diagnosis of a previously unknown lesion such as mitral stenosis is made.[3] The

Heart Disease and Pregnancy, 2nd edn. ed. Philip J. Steer and Michael A. Gatzoulis. Published by Cambridge University Press. © Cambridge University Press 2016.

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Section 2: Antenatal Care: General Considerations

Table 6.1  Predictors of maternal cardiovascular events and risk score from the CARPREG study Prior cardiac event (heart failure, transient ischemic attack, stroke before pregnancy, or arrhythmia) Baseline NYHA functional class >II or cyanosis Left heart obstruction (mitral valve area 50 mmHg)   Mechanical valve prosthesis   Moderate–severe systemic atrioventricular valve regurgitation (possibly related to ventricular dysfunction)   Moderate–severe subpulmonary atrioventricular valve regurgitation (possibly related to ventricular dysfunction)   Use of cardiac medication prepregnancy   Repaired or unrepaired cyanotic heart disease Predictors from Khairy [5]   Smoking history   Reduced subpulmonary ventricular function and/or severe pulmonary regurgitation NYHA = New York Heart Association Adapted from Regitz-Zagrosek et al. [9] ] with permission Table 6.3  Modified WHO classification of maternal cardiovascular risk: Principles

Risk class

Risk in pregnancy by medical condition

I

No detectable increased risk of maternal mortality and no/mild increase in morbidity.

II

Small increased risk of maternal mortality or moderate increase in morbidity.

III

Significantly increased risk of maternal mortality or severe morbidity. Expert counseling required. If pregnancy is decided upon, intensive specialist cardiac and obstetric monitoring needed throughout pregnancy, childbirth, and the puerperium.

IV

Extremely high risk of maternal mortality or severe morbidity; pregnancy contraindicated. If pregnancy occurs, termination should be discussed. If pregnancy continues, care as for class III.

WHO = World Health Organization Adapted from Regitz-Zagrosek et al. [9] with permission

The risk of a child being born with CHD in the general population is estimated to be 0.8%. The risk of a structural cardiac lesion in the offspring of a parent with CHD ranges from 2% to 50% (e.g. for 22q11 deletion or Marfan syndrome). This requires a detailed discussion with the woman and her partner. The woman’s own experience with her heart disease may affect how she views the risk of her child being born with a congenital heart defect. The long-term prognosis for the woman should be discussed as well.[11] She may have a significantly

increased risk of premature death or disability, even without the pregnancy. This will be relevant to planning future childcare if she decides to go ahead with a pregnancy. There are also concerns about whether this pregnancy will worsen her long-term prognosis. This is certainly the case with peripartum cardiomyopathy and possibly with systemic right ventricle and tetralogy of Fallot.[12,13] Data on the effect of pregnancy on long-term outcome in these women are still very preliminary (Chapters 23 and 24). After these risks are understood and have been discussed, the focus will next be placed on what needs to be done to reduce these risks. This may involve some invasive intervention (Chapter  8), preferably prior to conception, and/or initiation of medication (e.g. severe aortic stenosis or a patient with atrial septal defect) and lifestyle changes (e.g. careful attention to salt intake for a patient with decreased systolic function). For some patients, termination of pregnancy needs to be seriously considered and the related discussion sensitively handled.

Organizing care and monitoring Once the maternal and fetal risk assessment has been completed and the decision has been made to continue with the pregnancy, arrangements can be made for their ongoing follow-up. Women who fall into the low-risk group of WHO I and II can reasonably be cared for by their local obstetrician and local cardiologist (Table  6.4). This group would include women with normal left ventricular

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Section 2: Antenatal Care: General Considerations

Table 6.4  Modified WHO classification of maternal cardiovascular risk: Application WHO I pregnancy risk   Uncomplicated, small, or mild:   pulmonary stenosis    patent ductus arteriosus    mitral valve prolapse

Table 6.5  Maternal factors that increase the risk of neonatal complications: Preterm birth, FGR, RDS, intraventricular hemorrhage, fetal/neonatal death Baseline NYHA class >II or cyanosis Maternal left heart obstruction Smoking during pregnancy Multiple gestation

 Successfully repaired simple lesions (atrial or ventricular septal defect, patent ductus arteriosus, anomalous pulmonary venous drainage)

Use of oral anticoagulants during pregnancy

  Atrial or ventricular ectopic beats, isolated

FGR = fetal growth restriction; NYHA = New York Heart Association; RDS = respiratory distress syndrome Adapted from Regitz-Zagrosek et al. [9] with permission

WHO II or WHO III pregnancy risk   WHO II (if otherwise well and uncomplicated)

Mechanical valve prosthesis

   Unoperated atrial or ventricular septal defect    Repaired tetralogy of Fallot   Most arrhythmias   WHO II–III (depending on individual)    Mild left ventricular impairment   Hypertrophic cardiomyopathy   Native or tissue valvar heart disease not considered WHO I or IV    Marfan syndrome without aortic dilatation   Aorta 50 mm in aortic disease associated with bicuspid aortic valve   Native severe coarctation LVEF = left ventricular ejection fraction; NYHA = New York Heart Association; WHO = World Health Organization Adapted from Regitz-Zagrosek et al. [9] with permission

46

systolic function, small left-to-right shunts, valvar regurgitation without ventricular dysfunction, or repaired defects without significant sequelae. This assumes that they have been fully evaluated and that the risk assessment is accurate. At times, it may be reasonable to refer even these individuals to a specialized center for an initial assessment and confirmation of their low-risk status. Patients in WHO class  III and WHO class  II–III are best managed by experienced and expert teams and specialized centers.[2] Such centers should be able to provide the full range of medical and perinatal care. The team should consist of an obstetrician and a cardiologist, as well as an anesthetist and later a neonatologist, as well as providing midwife support and social support as necessary. Care will be easier if the obstetrician and the cardiologist can see the woman together at the same location. Such an arrangement enhances communication among all members of the team. Careful planning and communication are essential in the management of the higher risk pregnancy. The frequency of the antenatal visits will depend significantly on the severity of the woman’s underlying cardiac problem and will have to be adjusted to deal with changes in her status. It cannot be emphasized enough that careful documentation of findings and plan of management should be discussed with the patient and all members of the team, and should be available for review by the on-call cardiologist. Decisions about endocarditis prophylaxis, as well as plans for anesthesia, labor and delivery, and pediatric care need to be clearly spelled out. Some women will require increased postpartum monitoring and prolonged postpartum hospital stay because of their particular lesion. The availability of the plans for management and delivery is critical because the patient may present at any time,

Chapter 6: Cardiac monitoring during pregnancy

and not necessarily when the usual members of her team are on duty. This is also important for the woman who is being cared for by a specialized unit but who may live some distance away. She may well present to her local hospital and it will be important that all her information is freely available to the local physician as well as to the specialized unit cardiologist who is being called about her. The use of electronic medical records can facilitate such availability; however, an acceptable alternative is the UK system, whereby women carry their own clinical records and a copy of the key data is kept in the hospital. Many years’ experience of this approach shows that it is very rare for women to lose their own notes (after all, their proper care depends upon the notes being readily available when needed, so they have a major incentive to keep them safe), whereas lost or unavailable notes within the hospital system is a common phenomenon. A complete history and physical examination should be documented at the initial assessment. The cardiologist will need to make a careful repeat assessment at each visit, looking for changes of significance. It is common for pregnant women even without heart disease to complain of fatigue, dyspnea, palpitation, or pedal edema. It can be challenging to distinguish the symptoms of a normal pregnancy from those of early heart failure. On examination, pregnancy can frequently be associated with a systolic ejection murmur as well as a physiological third heart sound. It is important to decide under which circumstances a third heart sound becomes a concern. Blood pressure deserves special attention. Pre-existing cardiac disease does not protect the woman from preeclampsia, and preeclampsia can be particularly troublesome in the setting of complex cardiac disease. Oxygen saturation should be measured regularly and may be of special concern in women with open shunts. The usual decrease in peripheral vascular resistance may facilitate right to left shunting and will need to be carefully followed. Regular fetal assessment is very important and will have implications regarding the cardiac management of the woman. Evidence of fetal growth restriction may indicate inadequate cardiac output and may prompt a change in treatment or constitute sufficient grounds for invasive intervention. For the patient on medication, it is important to establish their usual level of compliance. This is especially true of the pregnant patient with PH who is receiving advanced therapies. Careful monitoring of anticoagulation is critical and the patient needs to

understand how important it is for her to have ongoing blood investigations for optimal anticoagulation. Patients on diuretics and those with decreased systolic function should have regular assessment of electrolytes and renal function. The urine should be checked for protein. Patient monitoring in hospital and postpartum will depend on the complexity and the severity of the heart disease, and the progression of the pregnancy. The previously formulated plans will provide guidance on the degree of monitoring required, keeping in mind that the clinical situation may change and warrant reconsideration of the degree of monitoring. Usually, close attention to blood pressure, heart rate, and rhythm is sufficient, with oxygen saturation monitoring needed for those with heart failure and cyanotic lesions. Invasive monitoring is usually only considered for patients with symptomatic aortic stenosis or mitral stenosis, worsening hypotension, Eisenmenger syndrome, or PH. Invasive monitoring with an arterial line and a central venous catheter is recommended for patients with Eisenmenger syndrome or PH. The use of a pulmonary artery catheter in this setting remains controversial.[14] Some women, such as those with Marfan syndrome or PH, may require more prolonged monitoring in hospital after delivery, as well as closer attention for weeks and months postpartum. In general, a follow-up assessment at 6–8  weeks is advisable and plans are necessary regarding long-term cardiology follow-up because the woman still has her underlying cardiac disease that continues to require ongoing assessment and management. Repeat imaging is frequently undertaken at 6–9 months, after the majority of the cardiovascular remodeling effects of pregnancy have worn off. There have been concerns that the pregnancy itself may contribute to worsening of the underlying cardiac lesion but there are insufficient data to provide good guidance (Chapters 23 and 24).

Echocardiography Echocardiography is central to the management of the pregnant woman with heart disease. It is readily available, can be performed safely throughout gestation, and allows a more precise definition of the presence and severity of cardiac lesions and serial assessment of ventricular function compared with clinical assessment alone. A  detailed description of physiological changes and cardiac remodeling related to pregnancy

47

Section 2: Antenatal Care: General Considerations

Figure 6.1  Left, apical four-chamber view in a patient showing increased wall thickness of left ventricular lateral wall and mid to distal septum (arrows). The restrictive physiology was unmasked during pregnancy by increased circulatory volume and patient developed pulmonary edema during delivery. The four pictures to the right show speckle tracking of the left ventricle of the same patient showing decreased left ventricular global strain suggesting myocardial disease. For the color version, please refer to the plate section. In some formats this figure will only appear in black and white.

is given in Chapter 3. Understanding these changes is crucial to anticipating and recognizing the effects of these changes on various cardiac lesions. The added hemodynamic burden of pregnancy may unmask a previously well-compensated or undiagnosed lesion. The frequency of echocardiography surveillance required is related to the cardiac condition and the clinical assessment. In our practice, echocardiography is usually performed at the initial assessment during pregnancy and then repeated (in all except the low-risk patients) toward the end of the second trimester when the hemodynamic changes have almost reached a maximum. In high-risk conditions, for example cardiomyopathy, PH, or aortopathy, more frequent echocardiographic studies are recommended.[1,2] Congenital and structural heart disease encompasses a broad spectrum of lesions and each patient is potentially unique. Therefore, an exhaustive approach to their echocardiographic assessment is outside the scope of this chapter. However, for all heart disease and pregnancy the essential information provided should include: 1. Ventricular size and function 2. Valvar abnormality and function 3. Estimation of cardiac pressures, in particular pulmonary artery pressure 4. Aortic dimensions.

48

Ventricular size and function Measurement of systolic ventricular function has been shown to enable a degree of prediction of future cardiac events. A systemic ventricular ejection fraction 70 mmHg) cardiopulmonary bypass to match expected maternal cardiac output (cardiac index of 2.6–3 l/min/m2) is recommended. The necessity of pulsatile perfusion remains controversial. 7. Avoid deep hypothermia. The maternal temperature should not be allowed to fall below 30°C. 8. Avoid hyperkalemia by using cardioplegia recovery techniques and close monitoring of maternal potassium levels. 9. Continuous monitoring of uterine contractions and fetal HR are recommended. Intraoperative fetal echocardiography should be considered.

Chapter 8: Surgical and catheter intervention during pregnancy in women with heart disease

Table 8.2  Relevant radiation quantities

Conversion between old and new units

Units of measurement

What it is

What it measures

Absorbed dose

gray (Gy) or milligray (mGy) (rad or millirad [mrad])

The amount of energy locally deposited in tissue per unit mass of tissue

Measures concentration of energy deposition in tissue

Assesses the potential biological risk to that specific tissue

1 rad = 10 mGy

Effective dose

sievert (Sv) or millisievert (mSv) (rem or millirem [mrem])

An attributed whole-body dose that produces the same whole-person stochastic risk as an absorbed dose to a limited portion of the body

Converts any localized absorbed or equivalent dose to a whole-body risk factor

Permits comparison of risks among several exposed individuals, even though the doses might be delivered to different sets of organs in these individuals

1 rem = 10 mSv

Equivalent dose

sievert (Sv) or millisievert (mSv) (rem or millirem [mrem])

A dose quantity that factors in the relative biological damage caused by different types of radiations

Provides a relative dose that accounts for increased biological damage from some types of radiations

This is the most common unit used to measure radiation risk to specific tissues for radiation protection of personnel

1 rem = 10 mSv

Quantity

Why it’s useful

Adapted with permission from Hirshfeld et al. [35]

10. The presence of an experienced obstetric team is required for fetal monitoring and to deal with precipitous delivery or the need for cesarean section (surgical equipment for cesarean section must be readily available). 11. Consideration should be given to postponing the surgery for as long as possible to allow fetal maturity. Delivery of the fetus prior to cardiopulmonary bypass avoids the risk of fetal loss but incurs the risks of prematurity for the child. Careful consultation with the obstetrician and neonatologist are necessary before considering such a preterm delivery.

Radiation and contrast agent risks to fetus and mother Percutaneous cardiac interventions during pregnancy have ranged from PBMV, to percutaneous coronary intervention, and to implantable automatic cardioverter defibrillator insertion.[31–33] These percutaneous cardiac interventions for specific lesions during pregnancy appear to be associated with a lower risk of fetal loss compared with surgery with cardiopulmonary bypass, but they expose the mother and fetus to the risks of ionizing radiation and the use of contrast medium. The maternal radiation risks for complications such as

skin injury, cataracts, neoplasm, and heritable genetic effects are likely to be similar to those of nonpregnant patients, although the risk of breast cancer may be a little higher because of increased cellular activity in the breast during pregnancy. The estimated effective dose during invasive cardiology procedures is between 1 and 20 mSv, but can be as high as 45 mSv for a long, complex percutaneous coronary intervention or ablation.[34] To put this into perspective, it is important to note that the annual effective dose delivered to an individual in the USA by natural background radiation is 3–4  mSv.[35] The major concern about the radiation risk focuses on the fetus, and the extent of that risk depends on the absorbed radiation dose and gestational age at the time of exposure. Recent reviews and guidelines have helped to put the issue of fetal risks from radiation exposure into perspective.[35–37] Much of the data on the safety and long-term consequences of radiation have involved follow-up monitoring of non-X-ray exposure, such as in survivors of the atomic bombings in Japan. Any discussion of radiation risks requires some understanding of the measurement of radiation dose and its nomenclature. There have been changes in the nomenclature over the years. There are a number of radiation measurement parameters: the most clinically valuable ones are summarized in Table 8.2. The older units are also included to allow

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Section 2: Antenatal Care: General Considerations

comparison with previously quoted standards and reports.[37] It should be noted that for X-rays, gamma rays, and electrons there is really no difference between absorbed dose and equivalent dose, i.e. 1 mGy = 1 mSv. For the clinical purposes of this discussion, there is no practical difference between measurements in milli­ grays and those in millisieverts. The risk to the fetus is best expressed by the absorbed dose.[36] Ionizing radiation exposure to the fetus can manifest its deleterious effects in three main ways: 1. Cell death and teratogenesis (deterministic effect) 2. Carcinogenesis (stochastic effect) 3. Genetic effects or mutations in germ cells, for which there are no long-term data. Exposure to extremely high-dose radiation (1000–2000 mGy) in pregnant animals results in teratogenic effects in all. During the time of active organogenesis (up to 42 days), radiation exposure may cause severe structural abnormalities. The greatest risk of central nervous system effects occurs at 8–15 weeks of gestation. It can be stated confidently that the fetal risks of malformation, growth restriction, resorption, or miscarriage are not increased with radiation doses of II or cyanosis during the baseline prenatal visit

Baseline NYHA class >II or cyanosis

Maternal left ventricular obstruction

Left heart obstruction (mitral valve area 44% is associated with an increase in birthweights

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Section 3: Antenatal Care: Fetal Considerations

Table 10.3  Live birth rates associated with various maternal oxygen saturation and hemoglobin levels

Live birth rate (%)

Hb (g/dl)

Live birth rate (%)

>90

92

20

 8

SaO2 (%)

Data from Whittemore et al. (1982) [8]

below the 50th centile, and the live birth rate falls to 8% if the maternal hemoglobin is >20 g/dl. If the maternal oxygen saturation falls below 85%, it is predictive of poor pregnancy outcome, with a 12% live birth rate (Table 10.3).[8] Another series reported by Presbitero et al. examined 1238 women with CHD in London and Italy.[9] The incidence of maternal cardiovascular complications was high (32%) and included one death from endocarditis 2  months after delivery. Of 96 pregnancies, 43% resulted in a live birth, 37% (n=15) of which were premature. There were 49 spontaneous miscarriages at between 6  weeks and 5  months of gestation and 6 stillbirths at 26–38 weeks. The mean birthweight at term was 2575 g (range 2100–3600 g). The basic maternal cardiac abnormality also influences fetal outcome. Women with single ventricles, tricuspid atresia, tetralogy of Fallot, or pulmonary atresia were found to have a worse pregnancy prognosis compared with those with, for example, Ebstein anomaly with an atrial septal defect, corrected transposition of the great arteries, a ventricular septal defect, or pulmonary stenosis.

Cyanotic vs acyanotic heart disease The fetal and maternal outcome for pregnant women with acyanotic heart disease is more favorable. Chia et al. retrospectively examined 19 151 deliveries with 143 cases of acyanotic heart disease.[10] The study found no significant difference in the rate of induction, use of epidurals, or operative deliveries between the acyanotic heart disease group and the group without heart disease. Perinatal mortality rates were not significantly different in the two groups (15.3 per 1000 vs 14 per 1000). Conversely, cyanotic CHD is associated with reduced fertility as well as increased fetal loss. This is because cyanosis worsens owing to increased intracardiac right to left shunting as peripheral vascular resistance falls. For example, the right to left shunt

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in Eisenmenger syndrome, which occurs as a result of a fixed and high pulmonary vascular resistance, increases during pregnancy. Thromboembolic risk is increased owing to erythrocytosis secondary to hypoxemia. Maternal cyanosis is poorly tolerated by the fetus and is associated with a high incidence of fetal loss (28%), stillbirths, FGR (30%), and preterm delivery (55%), both iatrogenic and spontaneous. [11] This is especially true if oxygen saturation falls below 80–85%. Sawhney et  al. compared 251 pregnancies in women with acyanotic heart disease with 24 pregnancies in women with cyanotic heart disease.[12] The incidences of miscarriage (8.3%), stillbirth (0.8%), and SGA babies (36.4%) were higher in women with cyanotic heart disease than in those with acyanotic heart disease (stillbirth 0.8%, SGA 6.9%). Cyanotic conditions that have been surgically repaired are not associated with an increased risk to either mother or fetus. Cardiac surgery improves perinatal outcome in women with cyanotic heart disease. A  recent review of women with surgically corrected tetralogy of Fallot showed that pregnancy is well tolerated, generally with a good neonatal outcome. However, the risk of congenital cardiac disease in the offspring is increased.[13] Whittemore et al. observed that live births occurred in only 42% of pregnancies with unrelieved cyanosis, but in 72% with palliative shunts and in 78% with surgical repair.[8] These data were reported in 1982 and should thus be interpreted with caution because there have since been major advances in the treatment of CHD. There are about 100 new Fontan repairs performed each year in the UK. This is a form of surgical palliation for patients who have only one effective ventricular chamber. It involves directly connecting the systemic venous return to the pulmonary arteries, although the precise method of doing this has varied over the last 20 years. While it is likely that not all of these patients will reach reproductive age in 10–20 years’ time, and half are men, they clearly represent a relatively small but important group of women at high risk during pregnancy. Pregnancy carries additional risk owing to the increased hemodynamic burden on the Fontan circulation itself and the single ventricular chamber. It is associated with a 2% risk of maternal mortality. Spontaneous miscarriage is frequent and occurs in up to 40% of pregnancies, probably as a result of congestion of the intrauterine veins. Women with a successful Fontan repair with a small right atrium or total

Chapter 10: Fetal care and surveillance in women with congenital heart disease

Table 10.4  Risk of recurrent disease in offspring of parents with congenital heart disease

Lesion

Mother affected risk of transmission (%)

n (%)

11.6

43 (5)

4.3

23 (1)

Atrioventricular septal defect

Father affected risk of transmission (%)

n (%)

Aortic stenosis

8.0

248 (36)

3.8

469 (18)

Coarctation

6.3

222 (14)

3.0

299 (9)

Atrial septal defect

6.1

969 (59)

3.5

451 (16)

Ventricular septal defect

6.0

731 (44)

3.6

717 (26)

Pulmonary stenosis

5.3

453 (24)

3.5

396 (14)

Persistent ductus arteriosus

4.1

828 (39)

2.0

245 (5)

Tetralogy of Fallot

2.0

301 (6)

1.4

362 (5)

Total

5.8

3795 (222)

3.1

2961 (93)

Data from Nora (1994) [18]

cavopulmonary connection and in NYHA class  I  or II can probably complete pregnancy, with a successful live birth rate of 45%, if not more.[14]

Valvar heart disease Regurgitant valvular disease is much better tolerated than stenotic. Mitral stenosis is associated with 10% maternal mortality, which increases to 50% when patients are in NYHA class III or IV; fetal mortality is accordingly high (12–31%). This is because a gradient develops between the left atrium and ventricle and the resultant increase in left atrial pressure can cause pulmonary edema, a rise in pulmonary arterial and right ventricular pressures, and eventually right ventricular dysfunction and failure. Surgical commissurotomy or, nowadays, balloon mitral valvotomy has been performed for severe mitral stenosis (mostly in the second trimester of pregnancy) with marked symptomatic relief and good maternal and fetal outcomes. However, mitral valve surgery, in particular, should be reserved only for selected women (see Chapter 8).[15] Hameed et  al. reported a significantly increased preterm delivery rate (23% vs 6%; p=0.03) and FGR (21% vs 0%; p50 mm.

Turner syndrome Assisted fertility techniques are now available to enable pregnancy in patients with Turner syndrome. This has highlighted the potential for dissection in this population. In the nonpregnant Turner population, about

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16–33% has a degree of aortic root enlargement.[47] Dissection can occur in the absence of any known risk factors. These risks go up in those with a 45X karyotype or hypertension, or those who have multiple pregnancies. When assessing risk in these patients, the aortic measurements need to be corrected for body surface area because of their short stature. The risk of dissection increases once the aorta is >2 cm/m2. The largest series of pregnancies in Turner patients was reported from Scandinavia. It described 122 pregnancies: 50% were complicated by hypertensive disorders and only 2 with cardiovascular complications.[48] However, pregnancy is thought to be a significant risk for these women and patients should be encouraged to seek cardiology review prior to embarking on any fertility treatments.

Ehlers–Danlos type IV syndrome: Vascular Ehlers–Danlos type IV syndrome produces a widespread vasculopathy in addition to its more generalized connective tissue effects. This disorder is secondary to a mutation in the COL3A1 gene, and by the age of 40 years 80% of patients will have already experienced a life-threatening cardiovascular event. In addition to large artery rupture, visceral (bowel and uterus) and vein rupture have been reported during pregnancy. Uterine hemorrhage is also common, and elective cesarean is recommended rather than vaginal delivery because of the risk of uterine rupture. Overall maternal mortality may be as high as 20%.[49] The beta-blocker celiprolol may ameliorate these risks in the nonpregnancy setting, but there are no data on its utility during pregnancy. Fortunately, type IV is relatively rare and other more common forms have a more benign course.

Takayasu’s arteritis Another rare cause of aortopathy in pregnancy is Takayasu’s arteritis. Dissection is rare. Severe hypertension, arterial occlusions, and acute aortic regurgitation are more common. In the largest series, about 25% of pregnancies resulted in fetal death.[50]

Conclusions Aortopathies include a wide range of acquired, genetic, and congenital disorders, many of which have multisystem involvement. Prepregnancy counseling is mandatory in women with a known or suspected aortopathy.

Chapter 12: Management of aortopathies, including Marfan syndrome and coarctation, in pregnancy

This should include a multidisciplinary discussion with appropriate genetic, cardiac, obstetric, anesthetic, and neonatal input. Although a diverse group of diseases, there are guiding principles that assist in making appropriate complex management plans that these patients require.

References   1. Huisman CM, Zwart JJ, Roos-Hesselink JW et al. Incidence and predictors of maternal cardiovascular mortality and severe morbidity in the Netherlands: A prospective cohort study. PLoS ONE 2013;8:e56494.   2. Cantwell R, Clutton-Brock T, Cooper G. Saving Mothers’ Lives. Reviewing maternal death to make motherhood safer 2006–2008. BJOG 2011;118(Supp.1):1–203.   3. Mabie WC, DiSessa TG, Crocker LG, et al. A longitudinal study of cardiac output in normal human pregnancy. Am J Obstet Gynecol 1994;170:849–56.   4. Robson SC, Hunter S, Boys RJ. et al. Serial study of factors influencing changes in cardiac output during pregnancy. Am J Physiol 1989;256:H1060–5.   5. Poppas A, Shroff SG, Korcarz CE et al. Serial assessment of the cardiovascular system in normal pregnancy. Role of arterial compliance and pulsatile arterial load. Circulation 1997;95:2407–15.   6. Gutin LS, Merz AE, Bakalov VK et al. Parity and aortic dimensions in healthy women. Int J Cardiol 2013;165(2):383–4.   7. Campisi D, Cutolo M, Carruba G et al. Evidence for soluble and nuclear site I binding of estrogens in human aorta. Atherosclerosis 1993;103:267–77.   8. Wingrove CS, Garr E, Godsland IF et al. 17-beta-oestradiol enhances release of matrix metalloproteinase-2 from human vascular smooth muscle cells. Biochim Biophys Acta 1998;1406:169–74.   9. Manallo-Estrella P, Barker AE. Histopathologic findings in human aortic media associated with pregnancy. Arch Path 1967;83:336–41. 10. Pedowitz P, Perell A. Aneurysms complicated by pregnancy. I. Aneurysms of the aorta and its major branches. Am J Obstet Gynecol 1957;73(4):720–35. 11. Pyeritz RE. Disorders of fibrillins and microfibrilogenesis: Marfan syndrome, MASS phenotype, contractural arachnodactyly and related conditions. In: Principles and Practice of Medical Genetics, 3rd edn. New York: Churchill Livingstone; 1996. 12. Lind J, Wallenburg HC. The Marfan syndrome and pregnancy: A retrospective study in a Dutch

population. Eur J Obstet Gynecol Reprod Biol 2001;98(1):28–35. 13. Meijboom LJ, Drenthen W, Pieper PG et al. Obstetric complications in Marfan syndrome. Int J Cardiol 2006;110:53–9. 14. Pini R, Roman MJ, Kramer-Fox R et al. Mitral valve dimensions and motion in Marfan patients with and without mitral valve prolapse. Comparison to primary mitral valve prolapse and normal subjects. Circulation 1989;80:915–24. 15. Schnitker MA, Bayer CA. Dissection aneurysm of the aorta in young individuals, particularly in association with pregnancy. Ann Intern Med 1944;29:486–511. 16. Williams GM, Gott VL, Brawley RK. et al. Aortic disease associated with pregnancy. J Vasc Surg 1988;8:470–5. 17. Hirst AE, Johns VJ, Kime SW. Dissecting aneurysm of the aorta: A review of 505 cases. Medicine (Baltimore) 1958;37:217–79. 18. Oskoui R, Lindsay J. Aortic dissection in women 1.5 1.0–1.5 80

  All of these estimates are influenced by ventricular function: the severity of aortic stenosis may be underestimated in the presence of impaired ventricular function a

Aortic stenosis: Introduction and pathophysiology In the UK, significant aortic stenosis is usually secondary to bicuspid aortic valve disease. Coexisting congenital cardiac lesions such as bicuspid aortopathy, aortic coarctation, and Shone syndrome should be considered when assessing the risk and management of pregnancy. Severe rheumatic aortic stenosis is not common in women of childbearing age; if present, it will almost certainly be in association with severe rheumatic mitral valve disease. Pregnancy is usually well tolerated in women with isolated mild and moderate aortic stenosis with good ventricular function. However, the increased circulating and stroke volumes of pregnancy result in an increase in left ventricular pressure and in pressure gradients across the stenotic aortic valve. This may result in a failure to increase coronary blood flow with consequent compromise to myocardial perfusion. Thus, pregnant women with severe aortic stenosis are at risk of developing symptoms for the first time, including dyspnea, angina, syncope, pulmonary edema, left ventricular failure, and sudden cardiac death. The risk of maternal death in severe aortic stenosis has been quoted as 17%, with a fetal mortality rate of 30%;[12] however, more recent data are encouraging,[13] with no pregnancy-related deaths in a series published in 2009.[14] Women with moderate or severe aortic stenosis, especially if symptomatic, are at an increased risk of needing aortic valve intervention within the first postpartum year.[14]

Prepregnancy assessment of isolated aortic stenosis As long as left ventricular dimensions and function are normal, coexistent aortic regurgitation does not appear to increase the risk of pregnancy in women with aortic stenosis.

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A history of symptoms including exertional dyspnea, chest tightness, or light-headedness in a woman with aortic stenosis is highly significant and suggests that aortic valve replacement should be performed before pregnancy. However, the majority of women with aortic stenosis seeking prepregnancy counseling are asymptomatic; they require careful assessment of their valve, ventricular function, and response to exercise (the latter being a surrogate for the increased cardiovascular demands of pregnancy). An asymptomatic woman with isolated aortic stenosis is likely to tolerate pregnancy well if: • the resting echocardiogram shows that ◦◦ left ventricular function is normal ◦◦ the pregnancy mean Doppler-derived aortic valve pressure gradient is