The Obstetrician & Gynaecologist 2007;9:2:83-87
doi: 10.1576/toag.9.2.083.27308
Copyright © 2007 by the Royal College of Obstetricians and Gynaecologists.
Cardiac disease in pregnancy. Part 2: acquired heart disease
Emily Gelson, BS MB BCh, Clinical Fellow in Pregnancy and Heart Disease1,
Mark Johnson, PhD MRCP MRCOG, Reader in Obstetrics and Obstetric Medicine2,
Michael Gatzoulis, MD PhD MRCP, Professor of Cardiology, Congenital Heart Disease3 and
Uebing Abselm, MD, Fellow in Adult Congenital Heart Disease3
1. Chelsea and Westminster Hospital, 369 Fulham Road, London SW10 9NH, UK Email: e.gelson{at}imperial.ac.uk (corresponding author)
2. Chelsea and Westminster Hospital, London, UK
3. Adult Congenital Heart Disease Unit, Royal Brompton and Harefield NHS Trust and; National Heart and Lung Institute, Imperial College, London SW3 6NP, UK
4. Adult Congenital Heart Disease Unit, Royal Brompton and Harefield NHS Trust and; National Heart and Lung Institute, Imperial College, London, UK
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Abstract
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Key content:- The incidence of both rheumatic and ischaemic heart disease is expected to increase in the UK because of changes in ethnicity and increasing maternal age.
- Effective management of valvular heart lesions is based on the treatment of symptoms, with the option of balloon valvuloplasty and valve replacement.
- Acute myocardial infarction poses a significant risk of maternal mortality and requires prompt treatment with heparin, beta-blockers and nitrates.
- Peripartum cardiomyopathy, although rare, is associated with significant maternal mortality and morbidity.
Learning objectives:
- To know about the causes of acquired heart disease in pregnancy.
- To understand the general management principles for valvular heart lesions, ischaemic heart disease and cardiac arrhythmias when encountered during pregnancy.
Ethical issues:
- Warfarin is teratogenic if used in the first trimester. Is it ethical not to use it, knowing that it reduces the risk of valve thrombosis and maternal mortality?
Please cite this article as: Gelson E, Johnson M, Gatzoulis M, Uebing A. Cardiac disease in pregnancy. Part 2: acquired heart disease. The Obstetrician & Gynaecologist 2007;9:83–87.
Keywords cardiac arrhythmias / cardiomyopathy / ischaemic heart disease / pregnancy / valvular heart disease
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Introduction
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The incidence of heart disease during pregnancy in the United Kingdom has remained constant at 0.9% for several decades.1 However, the severity of heart disease and the risk it poses during pregnancy appear to be increasing. Heart disease recently re-emerged as one of the leading causes of maternal mortality (2.2 per 100 000) and is now the most common cause of indirect maternal death in the UK (Figure 1).2 Pregnancy not only poses a risk of maternal mortality but also of serious morbidity such as heart failure, stroke and cardiac arrhythmia. The fetus is not spared: neonatal morbidity and mortality from fetal growth restriction and prematurity are markedly increased.3 In the second part of this article we review acquired heart disease and cardiac arrhythmias in pregnancy.
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Causes of acquired heart disease
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The decline in rheumatic fever in the developed world has led to a decrease in the incidence of valvular heart disease in pregnancy in the UK. With increasing immigration from countries where rheumatic fever remains prevalent, valvular heart disease is set to become a significant problem. In this context, valvular heart disease is often first recognised during pregnancy, when increased demands on the heart trigger symptoms.4 Although rare, ischaemic heart disease is increasing in pregnancy. This is the result of changes in UK ethnicity, leading to an increasing incidence of diabetes, obesity and smoking, and an increase in maternal age at first pregnancy.
Pregnancy induced cardiomyopathy occurs predominantly around the time of delivery in women with multiple pregnancy and/or pre-eclampsia.5 Cardiac arrhythmias are also an important cause of maternal morbidity.
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Valvular heart disease
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Regurgitant valvular abnormalities are generally better tolerated in pregnancy than stenotic valvular abnormalities.
Mitral stenosis
Rheumatic mitral stenosis is the most common clinically significant valvular lesion in pregnancy.6 The rise in heart rate and stroke volume increases the pressure gradient across the narrowed mitral valve. This leads to an increase in left atrial pressure and the development or worsening of symptoms including dyspnoea, decreased exercise capacity, orthopnoea, paroxysmal nocturnal dyspnoea and pulmonary oedema. The risk of deterioration persists into the puerperium. Increased left atrial pressure also increases the risk of atrial fibrillation, which can lead to an uncontrolled ventricular rate and heart failure. Mortality among pregnant women with minimal symptoms is less than 1%, with a neonatal mortality rate of 12–31%.7 Women with severe symptoms (New York Heart Association [NYHA] class III or IV) or severe stenosis (valve area <1 cm) should delay conception until after surgical correction. During pregnancy medical therapy is directed at minimising volume overload through bed rest and diuretics and optimising ventricular filling with beta blockade. Atrial fibrillation requires prompt treatment with DC cardioversion, beta-blockers or digoxin. Balloon mitral valvuloplasty is indicated with refractory symptoms despite optimal medical therapy and is safe and effective during pregnancy.8
Mitral valve prolapse
Mitral valve prolapse is the most common cardiac abnormality in the pregnant population, affecting 12–17% of women of childbearing age. Mitral valve prolapse without regurgitation does not affect the cardiovascular response to pregnancy and, thus, seldom gives rise to cardiovascular complications.9
Mitral regurgitation
Mitral regurgitation during pregnancy is usually due to rheumatic valvular disease or mitral valve prolapse. Because of the fall in systemic vascular resistance and reduced left ventricular afterload, mitral regurgitation is usually well tolerated during pregnancy. Asymptomatic women do not require therapy during pregnancy. Symptomatic heart failure can be treated with nitrates, hydralazine, diuretics and digoxin.
Aortic stenosis
In young women aortic stenosis is usually congenital in origin. Pregnancy outcome is dependent on the degree of stenosis.10 The limited ability of the left ventricle to augment cardiac output results in an abnormal elevation of left ventricular systolic and filling pressures. The hypertrophied ventricle is sensitive to falls in preload, leading to a risk of angina, hypertension, heart failure and arrhythmia.10 Women who are symptomatic or who have severe stenosis (peak outflow gradient >80 mmHg) or left ventricular dysfunction are advised to delay conception until after surgical correction. If a pregnant woman becomes symptomatic or is so when pregnancy is confirmed, bed rest should be advised and valve replacement considered. Wherever possible, open heart surgery with the need for cardiac bypass should be avoided as it carries a 1.5–5% maternal mortality and a 16–33% fetal mortality, with no relation to gestational age.11 Fetal mortality can, however, be reduced to 10% by avoiding hypothermia and maintaining perfusion pressures. Aortic balloon valvuloplasty may be used as a palliative procedure, allowing deferral of valve replacement until after delivery.12
Prosthetic heart valves
Bioprosthetic valves are not associated with increased risk and they do not degenerate more rapidly during pregnancy.13 In contrast, pregnancy in women who have had mechanical valve replacement is associated with a 45% incidence of thrombotic episodes, with a maternal mortality rate of 1–4%. Effective anticoagulation is critical and the risks to the mother and fetus need to be carefully balanced; several approaches are available (Table 1).14 To avoid valve thrombosis the most effective option for the mother is to take warfarin for the duration of the pregnancy, stopping at 38 weeks for elective caesarean delivery, with intravenous heparin perioperatively. The benefit is a low rate of maternal thromboembolism (4%) while, in contrast, the risk of fetal abnormality is high (6%). A strategy of substituting low molecular weight heparin (LMWH) for warfarin during the period of organogenesis (6–12 weeks of gestation) abolishes the risk of warfarin embryopathy but doubles the maternal thromboembolism rate to 9%. Low molecular weight heparin throughout pregnancy again abolishes the risk of warfarin embryopathy but is associated with a 25% risk of valve thrombosis. Low dose aspirin has been used as an adjunct to heparin with successful outcomes. Monthly anti-factor Xa levels should be used to monitor the therapeutic effect of LMWH, with levels ideally maintained within the high therapeutic range. Regardless of whether heparin or warfarin is used, the risk of fetal loss is up to 30%. Women should be advised of this and an informed choice must be made based on relative risk and benefit.
Endocarditis prophylaxis
Antibiotic prophylaxis should be given during labour and delivery for all women with valvular lesions except mitral valve prolapse without regurgitation.
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Ischaemic heart disease
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Acute myocardial infarction is rare during pregnancy and the puerperium, occurring in one in 10 000 pregnancies. Maternal mortality rates of 37–50% have been reported, with most deaths occurring at the time of infarction.15 Pregnancy itself has not been identified as a risk factor for acute myocardial infarction. However, the increased blood volume, altered haemodynamics and increase in estrogen and progesterone levels are likely to be risk factors for cardiovascular disease.16 The incidence of pregnancy-related acute myocardial infarction and prevalence of certain cardiovascular risk factors are increasing because of increases in maternal age, diabetes and obesity.17 Treatment of myocardial infarction during pregnancy is the same as that outside pregnancy, with heparin, beta-blockers and nitrates. Coronary angiography is safe in pregnancy and percutaneous catheter intervention is used as the first-line treatment. Thrombolysis can cause bleeding from the placental site but is still indicated in the management of acute myocardial infarction.
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Cardiac arrhythmias
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Pregnancy increases the incidence of cardiac arrhythmia. This is the result of hormonal changes, alterations in autonomic tone, increased haemodynamic demands and mild hypokalemia. These factors act to precipitate cardiac arrhythmias not present before pregnancy or to exacerbate pre-existing arrhythmias. The risk is highest during labour and delivery.
Atrial and ventricular premature beats are frequently present during pregnancy. They have no adverse effects on the mother or fetus and require no further investigation. The risk of both new onset and exacerbation of supraventricular tachycardia (SVT) is increased during pregnancy.18 Atrial fibrillation and atrial flutter are rare and can be caused by pre-existing congenital or valvular heart disease, thyrotoxicosis or electrolyte imbalance. Because of the risk of thromboembolism and the potential detrimental effect on the fetus, early treatment, either with conversion to sinus rhythm or ventricular rate control, is important. Other causes of SVT encountered in pregnancy are re-entrant tachycardias; for example, Wolff–Parkinson–White syndrome and Lown–Ganong–Levine syndrome. Initial treatment in the haemodynamically stable woman to terminate an SVT should involve the vagal manoeuvre. If this fails, intravenous adenosine can be used safely. Second-line treatments include digoxin, beta-blockers and calcium channel blockers.
Ventricular tachycardia is uncommon in pregnancy. It is usually associated with underlying heart disease but new onset ventricular tachycardia without structural heart disease has been reported.19 Initial therapy with lidocaine or procainamide should be considered in haemodynamically stable women. Amiodarone is contraindicated, as it is associated with fetal hypothyroidism, growth restriction and prematurity. Beta-blockers and sotalol are used prophylactically. Electrical cardioversion is safe in pregnancy and necessary in all women with tachyarrhythmias who are haemodynamically unstable. Attention should be paid to airway management to reduce the risk of aspiration/regurgitation of gastric content and care should be taken to avoid the supine position and, thus, aortocaval compression.
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Cardiomyopathy
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Dilated
Pregnancy is poorly tolerated in women with dilated cardiomyopathy. There is a 7% mortality rate with NYHA class III or IV and a risk of heart failure, irreversible left ventricular dysfunction and fetal loss. Women should be advised of these risks when contemplating pregnancy. In the event of an unplanned pregnancy a termination of pregnancy should be offered.
Hypertrophic
Clinical and genetic screening of families with hypertrophic cardiomyopathy and the widespread use of echocardiography has led to the identification of increasing numbers of women with the condition who previously would have been unaware of it. Pregnancy in asymptomatic women is usually well tolerated.20 However, in those women with heart failure or severe symptoms before pregnancy, there is a risk of symptomatic progression, atrial fibrillation, syncope and maternal death.21
Peripartum
Peripartum cardiomyopathy is a disorder in which left ventricular systolic dysfunction and heart failure present in the last month of pregnancy and the first 5 months post delivery. It is a rare condition, with an estimated incidence of 1 case per 2 289 live births.22 Women present with signs and symptoms of left ventricular failure. Peripartum cardiomyopathy is a diagnosis of exclusion. Therefore, all other causes of dilated cardiomyopathy with heart failure must be excluded. Adequate treatment with beta-blockers, diuretics, hydralazine and digoxin reduce mortality rates and improve overall prognosis. ACE inhibitors replace hydralazine post partum. Twenty percent of women with the disorder either die or survive only because they receive cardiac transplantation. The remainder of women recover partially or completely. Subsequent pregnancy after a diagnosis of peripartum cardiomyopathy carries a higher risk of relapse if left ventricular systolic function is not fully recovered first and, even with full recovery, some additional risk of relapse remains.24 There is no consensus regarding recommendations for future pregnancies in women who have had peripartum cardiomyopathy.24
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Conclusion
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Cardiac disease in pregnancy is a leading cause of maternal and neonatal morbidity and mortality. The incidence of both rheumatic and ischaemic heart disease is expected to increase in the UK because of changes in ethnicity and increasing maternal age. Effective management of valvular heart lesions is based on the treatment of symptoms, with the option of balloon valvuloplasty and valve replacement. Acute myocardial infarction poses a significant risk of maternal mortality and requires prompt treatment with heparin, beta-blockers and nitrates. Peripartum cardiomyopathy, although rare, is associated with significant maternal mortality and morbidity. There is, as yet, no consensus on recommendations for future pregnancies.
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References
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- Steer PJ. Pregnancy and contraception. In: Gatzoulis MA, Swan L, Therrien J, Pantely GA, editors. Adult Congenital Heart Disease: a Practical Guide. Oxford: BMJ/Blackwell Publishing; 2005. p. 16–3.
- de Swiet M, Nelson-Piercy C. Cardiac disease. In: Confidential Enquiry into Maternal and Child Health. In: Why Mothers Die 2000–2002. The Sixth Report of the Confidential Enquiries into Maternal Deaths in the United Kingdom. London: RCOG Press; 2004. p. 137–5.
- Siu SC, Sermer M, Colman JM, Alverez AN, Mercier LA, Morton BC, et al. on behalf of the Cardiac Disease in Pregnancy (CARPREG) Investigators. Prospective multicenter study of pregnancy outcome in women with heart disease. Circulation 2001;104:515–21.[Abstract/Free Full Text]
- Tan J, de Swiet M. Prevalence of heart disease diagnosed de novo in pregnancy in a West London population. BJOG 1998;105:1185–8. doi:10.1111/j.1471-0528.1998.tb09972.x
- Sliwa K, Fett J, Elkayam U. Peripartum cardiomyopathy. Lancet 2006;368:687–93. doi:10.1016/S0140-6736(06)69253-2[Medline]
- Hameed A, Karaalp IS, Tummala PP, Wani OR, Canetti M, Akhter MW, et al. The effect of valvular heart disease on maternal and fetal outcome of pregnancy. J Am Coll Cardiol 2001;37:893–9. doi:10.1016/S0735-1097(00)01198-0[Abstract/Free Full Text]
- Silversides CK, Colman JM, Sermer M, Siu SC. Cardiac risk in pregnant women with rheumatic mitral stenosis. Am J Cardiol 2003;11:1382–5. doi:10.1016/S0002-9149(03)00339-4
- Sivadasanpillai H, Srinivasan A, Sivasubramoniam S, Mahadevan KK, Kumar A, Titus T, et al. Long-term outcome of patients undergoing balloon mitral valvotomy in pregnancy. Am J Cardiol 2005;95:1504–6. doi:10.1016/j.amjcard.2005.02.025[Medline]
- Lesniak-Sobelga A, Tracz W, KostKiewicz M, Podolec P, Pasowicz M. Clinical and echocardiographic assessment of pregnant women with valvular heart diseases – maternal and fetal outcome. Int J Cardiol 2004;94:15–23. doi:10.1016/j.ijcard.2003.03.017[Medline]
- Silversides CK, Colman JM, Sermer M, Farine D, Siu SC. Early and intermediate-term outcomes of pregnancy with congenital aortic stenosis. Am J Cardiol 2003;91:1386–9. doi:10.1016/S0002-9149(03)00340-0[Medline]
- Parry AJ, Westaby S. Cardiopulmonary bypass during pregnancy. Ann Thorac Surg 1996;61:1865–9. doi:10.1016/0003-4975(96)00150-6[Abstract/Free Full Text]
- Myerson SG, Mitchell AR, Ormerod OJ, Banning AP. What is the role of balloon dilatation for severe aortic stenosis during pregnancy? J Heart Valve Dis 2005;14:147–50.[Medline]
- El SF, Hassan W, Latroche B, Helaly S, Hegazy H, Shahid M, et al. Pregnancy has no effect on the rate of structural deterioration of bioprosthetic valves: long-term 18-year follow up results. J Heart Valve Dis 2005;14:481–5.[Medline]
- Chan WS, Anand S, Ginsberg JS. Anticoagulation of pregnant women with mechanical heart valves: a systematic review of the literature. Arch Intern Med 2000;160:191–6. doi:10.1001/archinte.160.2.191[Abstract/Free Full Text]
- Hankins GD, Wendel GD Jr, Leveno KJ, Stoneham J. Myocardial infarction during pregnancy: a review. Obstet Gynecol 1985;65:139–46.[Medline]
- Roth A, Elkayam U. Acute myocardial infarction associated with pregnancy. Ann Intern Med 1996;125:751–62.[Abstract/Free Full Text]
- James AH, Jamison MG, Bisawas MS, Brancazio LR, Myers ER. Acute myocardial infarction in pregnancy: a United States population-based study. Circulation 2006;113:1564–71. doi:10.1161/CIRCULATIONAHA.105.576751[Abstract/Free Full Text]
- Tawam M, Levine J, Mendelson M, Goldberger J, Dyer A, Kadish A. Effect of pregnancy on paroxysmal supraventricular tachycardia. Am J Cardiol 1992;72:838–40. doi:10.1016/0002-9149(93)91078-V
- Brodsky M, Doria R, Allen B, Sato D, Thomas G, Sada M. New onset ventricular tachycardia during pregnancy. Am Heart J 1992;123:933–41. doi:10.1016/0002-8703(92)90699-V[Medline]
- Thaman R, Varnava A, Hamid MS, Firoozi S, Sachdev B, Condon M, et al. Pregnancy related complications in women with hypertrophic cardiomyopathy. Heart 2003;89:752–6. doi:10.1136/heart.89.7.752[Abstract/Free Full Text]
- Autore C, Conte MR, Piccininno M, Bernabò P, Bonfiglio G, Bruzzi P, et al. Risk associated with pregnancy in hypertrophic cardiomyopathy. J Am Coll Cardiol 2002;40:1864–9. doi:10.1016/S0735-1097(02)02495-6[Abstract/Free Full Text]
- Mielniczuk LM, Williams K, Davis DR, Tang AS, Lemery R, Green MS, et al. Frequency of peripartum cardiomyopathy. Am J Cardiol 2006;97:1765–8. doi:10.1016/j.amjcard.2006.01.039[Medline]
- Elkayam U, Tummala PP, Rao K, Akhter MW, Karaalp IS, Wani OR, et al. Maternal and fetal outcomes of subsequent pregnancies in women with peripartum cardiomyopathy. N Eng J Med 2001;344:1567–71. doi:10.1056/NEJM200105243442101[Abstract/Free Full Text]
- Pearson GD, Veille JC, Rahimtoola S, Hsisa J, Oakley CM, Hosenpud JD, et al. Peripartum cardiomyopathy: National Heart, Lung, and Blood Institute and Office of Rare Diseases (National Institutes of Health) workshop recommendations and review. In: JAMA. 283, 2000. p. 1183–8.doi:10.1001/jama.283.9.1183.[Abstract/Free Full Text]
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Abstract
Introduction
