20 Pregnancy and Heart Disease Patrizia Presbitero, Giacomo G. Boccuzzi, Christianne J.M.
Transcription
20 Pregnancy and Heart Disease Patrizia Presbitero, Giacomo G. Boccuzzi, Christianne J.M.
TETC20 12/2/05 9:41 Page 607 20 Pregnancy and Heart Disease Patrizia Presbitero, Giacomo G. Boccuzzi, Christianne J.M. de Groot and Jolien W. Roos-Hesselink Summary Heart disease, though rare, can be present or discovered during pregnancy because of haemodynamic overload of the heart particulary during the third trimester when cardiac output doubles. Most of the knowledge in recognition and treatment of cardiac disease during pregnancy is not based on evidence from randomized trials, but is derived from clinical experience, few case reports and small consecutive series. These are summarized in the guidelines on “Management of Cardiovascular Diseases During Pregnancy” from the European Society of Cardiology, the basis for this chapter. The physiological changes that occur during pregnancy have a different impact depending on the type and severity of cardiac anomalies. Differential diagnosis with normal pregnancy related physiological changes is also discussed. Particular emphasis is placed on early and accurate diagnosis of congenital or acquired cardiac anomalies Cardiovascular adaptations during normal pregnancy Pregnancy physiology is characterized by significant haemodynamic changes that allow the uterus and developing fetus to receive an adequate blood supply. These adaptations are well tolerated by the normal heart but may result in haemodynamic problems for the diseased heart. This implies that pregnancy may unmask previously silent heart disease. Heart disease is present in 0.5–1% [1,2] of all pregnant because often early intervention is essential for a safe pregnancy and delivery. Women at low risk are those in NYHA class I or II with good ventricular function, without severe left ventricular inflow or outflow obstruction or pulmonary hypertension and who do not need to take anticoagulants. Women at high risk are those showing symptoms, of severe mitral or aortic stenosis or unoperated coarctation, with cyanotic congenital heart disease with or without pulmonary hypertension, with impaired left ventricular function and/or life-threatening arrhythmias. The same conditions that endanger the mother also affect fetal survival. Multiple therapeutic options including percutaneous or surgical intervention are now available to allow for a safe completion of the pregnancy. Management of these patients requires teamwork from cardiologists, obstetricians, anaesthetists, neonatologists and, sometimes cardiac surgeons. women and accounts for about 10–15% of all maternal mortality [3]. Although the incidence of acquired disease has fallen (to below 0.2%) in Western countries due to the reduction in the incidence of rheumatic fever following the introduction of penicillin [1,2], rheumatic heart disease is still the prevalent cause. Congenital heart disease is becoming an increasing problem during pregnancy as a result of the success of neonatal corrective or palliative cardiac surgery. Because of the increased delay to first pregnancy, maternal older age and the increase in women’s smoking habits, symptomatic coronary disease, although rare, can occur and is likely to increase. 607 TETC20 12/2/05 9:41 Page 608 Chapter 20 Haemodynamic changes during pregnancy The evaluation and management of heart disease in pregnant women require knowledge of the normal physiological changes associated with gestation, labour, delivery and the early postpartum period (Fig. 20.1). Blood volume and cardiac output The most remarkable change related to pregnancy is the increase in blood volume, which almost doubles by the end of pregnancy. It starts to increase from the sixth week, rising rapidly in the second trimester and becoming stable in the last 8 weeks [4]. Red cell mass increases later in pregnancy but to a lesser extent than the plasma volume, leading to slight haemodilution and the physiological anaemia of pregnancy, with haematocrit at about 33–34% and haemoglobin around 11–12 g/dl [5]. These changes are more marked in twin or multiple pregnancies. In the last trimester, peripheral arterial vasodilatation may reduce arterial vascular filling and thereby induce sodium and water retention mediated by aldosterone. In an average pregnancy, there is a gradual accumulation of 500–900 mEq of sodium and total body water increases by 6–8 litres, mostly extracellular. All these haemodynamic changes, which evolved to protect the mother from blood loss at delivery, could play a role in the pathogenesis of heart failure. Cardiac output also increases to about 40% above the non-pregnant value. Most of this increment is achieved early in pregnancy, with peak values at 20–24 weeks [6]. This is achieved by an increase in stroke volume and heart rate. In late pregnancy the increase in venous return is sensitive to posture: a sharp drop in preload due to inferior vena cava compression by the gravid uterus in the supine position may cause hypotension, with weak- 50 Increase (%) 608 CO 40 30 SV 20 HR 10 0 0 5 8 12 16 20 24 28 32 36 38 Weeks Figure 20.1 Increase in cardiac output (CO), stroke volume (SV) and heart rate (HR) during pregnancy. ness and light-headedness or syncope and even (short) fetal distress. These symptoms are easily resolved by turning the woman from the supine to the lateral decubitus position. Heart rate Heart rate starts to increase in the first weeks of pregnancy and peaks in the first half of the third trimester. The increase in resting heart rate averages 10–20 b.p.m. Atrial tachyarrhythmias can be present in normal pregnancy due to increased plasma catecholamine concentrations and/or adrenoreceptor sensitivity, and to the stretched atrial wall because of increased heart volumes [7]. Peripheral vascular resistance Maternal peripheral and pulmonary vascular resistance fall as a result of the low-resistance uteroplacental circulation, decreased mean aortic pressure and endogenous hormones. Recently, there has been a focus on the role of nitric oxide in the pathogenesis of vasodilatation [8]. Venous return increases, with a consequent rise in left ventricular end-diastolic volume, although the filling pressure does not rise because of ventricular structural changes (increased compliance). In the first two trimesters, the fall in systemic vascular resistance, which exceeds the increase in cardiac output, leads to a drop in both systolic and, especially, diastolic blood pressure, resulting in a wide pulse pressure. Labour, delivery and early postpartum period The most dramatic swings in haemodynamic parameters occur during labour, delivery and the immediate postpartum period. Uterine contractions significantly increase venous return, and during a contraction cardiac output may rise by a further 25%. Pain and anxiety cause an increase in sympathetic tone during the second stage of labour, which in turn enhances cardiac output and blood pressure. These changes may be influenced by the type of anaesthesia and analgesia used in labour and by the mode of delivery [9]. Reduction of pain and apprehension can be achieved by local and caudal anaesthesia. The patient should be lying in the left lateral position during labour. During the early postpartum period, cardiac output increases as a result of a blood shift from the contracting uterus to the systemic circulation and because of inferior vena cava decompression (autotransfusion) [10]. There are no haemodynamic differences between lactating and non-lactating mothers. The cardiovascular adaptations associated with pregnancy regress by approximately 6 weeks after delivery. TETC20 12/2/05 9:41 Page 609 Pregnancy and Heart Disease Cardiac evaluation in normal pregnancy During pregnancy, cardiovascular disease or worsening of a previous cardiac disease is difficult to detect: cardiopulmonary signs and symptoms typically reported during normal pregnancy may mimic heart disease. Fatigue and decreased exercise capacity are common, along with chest pain at rest that may be caused by oesophageal reflux. As many as 75% of women may complain of mild dyspnoea, whereas progressive orthopnoea or paroxysmal nocturnal dyspnoea are rare. Palpitations are very common and are due to either a physiological increase in the resting heart rate or atrial or ventricular ectopic beats [11] (Table 20.1). Physical examination The physical examination of a healthy pregnant woman shows a slightly fast resting heart, a bounding pulse, a widened pulse pressure and warm flushed peripheries. In addition, a slight elevation of venous pressure, the presence of ‘tense’ soft tissues and peripheral oedema (pedal oedema) are common. The precordial impulse is hyperkinetic and the first heart sound (S1) is increased, with prominent splitting that may be misinterpreted as a fourth heart sound (S4) or as a systolic click. During the later stages of pregnancy, the physiological splitting of the second heart sound (S2) may seem fixed. Third sound gallop (S3) is frequently present by week 20 of gestation, whereas S4 is uncommon and requires further evaluation. Murmurs develop in nearly all women during pregnancy. They are usually soft, mid-systolic and heard at the mid to upper left sternal border, and are secondary to increased pulmonary blood flow. Benign murmurs Table 20.1 Symptoms and signs during pregnancy include the continuous bruit resulting from increased blood flow to the breasts, the ‘mammary soufflé’, and the suprasternal venous hums, which can be obliterated through ipsilateral jugular digital compression or by firm pressure of the stethoscope. Diastolic murmurs are unusual and therefore call for further evaluation. The murmurs of stenotic heart valves (aortic stenosis, pulmonary stenosis, mitral stenosis) may increase in intensity because of the physiological increase in cardiac output and fall in systemic vascular resistance. On the other hand, the murmurs of incompetent heart valves (aortic insufficiency, mitral insufficiency) may decrease. Detection of murmurs as diastolic murmurs, continuous murmurs and loud systolic murmurs equal or greater than grade III in intensity cannot be considered physiological and hence need further careful examination, starting with transthoracic echocardiography (Table 20.1) [12]. Additional diagnostic tools Electrocardiogram In normal pregnancy, there are non-characteristic electrocardiographic changes except for a slight leftward shift of the electrical axis, which can give rise to a small Q wave in lead III [13]. Severe left-axis deviation is not a normal pregnancy variant and needs further evaluation. Doppler echocardiography Because of its safety and diagnostic power, Doppler echocardiography is the first advisable diagnostic tool. In a normal pregnancy, serial echocardiography usually shows a significant increase in cardiac output, cardiac index, left ventricular end-diastolic volume and left ventricular wall thickness. An increase in left (up to 6%) Normal pregnancy Indicators of heart disease Symptoms Mild dyspnoea Fatiguability Decreased exercise tolerance Rest chest pain Palpitations Severe or progressive dyspnoea Paroxysmal nocturnal dyspnoea Syncope with exertion Effort or emotion chest pain Signs Pedal oedema Warm extremities Full, sharp and collapsing pulse Prominent left ventricular impulse Third heart sound (S3) Grade 1–2 systolic ejection murmurs Premature beats Continuous murmurs Severe peripheral oedema Clubbing and cyanosis Persistent neck vein distension Cardiomegaly Fourth heart sound (S4) Grade ≥ 3 systolic ejection murmurs Sustained arrhythmias Diastolic murmurs 609 TETC20 12/2/05 9:41 Page 610 610 Chapter 20 and right (up to 12%) ventricular diastolic dimensions is present [14]. A mild increase in right atrial size (up to 20%) and transvalvular flow velocities and the presence of mild atrioventricular valve regurgitation are normal echocardiographic findings during pregnancy [15]. Chest radiography Exposure to ionizing radiation should be avoided whenever possible, especially during early pregnancy since malignancies and congenital abnormalities in offspring have been described. Routine chest radiography (1.5 mGy) exposes the uterus to a minimal (0.05 mGy) radiation dose. Chest radiography should therefore be used only if clinically indicated and performed with the minimum amount of radiation, shielding the pelvic area. In addition, whenever possible it should be delayed until at least the completion of the first trimester. In normal pregnancy, the heart may appear enlarged due to the horizontal position, and increased lung markings and small pleural effusions can be detected [16]. Assessment of heart disease in pregnancy The assessment of women with heart disease should take place before conception in order to counsel them adequately and to minimize maternal and fetal morbidity and mortality. The type and severity of cardiac disease, general conditions, previous cardiovascular and cerebral events, NYHA class, medications and obstetric and family history should be taken into account in evaluating the risks and possibility of successful pregnancy. For example, aortic insufficiency is normally well tolerated during pregnancy because of the low peripheral resistance; however, if systemic hypertension, NYHA class III– IV, an ejection fraction around 40% or ventricular arrhythmias are present, it becomes a high-risk condition. Counselling, surveillance and treatment of women with cardiac disease should be a collaborative effort including obstetric, cardiological and anaesthesiological services. The risk of recurrence in the offspring should be discussed. All patients with congenital heart diseases should have informed genetic counselling before conception (Table 20.2). An exercise test before pregnancy is very important for evaluating functional capacity. The physiological changes of pregnancy are similar to the ones that occur during exercise but over an extended period, so a good exercise test will predict a well-tolerated pregnancy. Echocardiography is required to assess cardiac haemodynamics, particularly pulmonary pressure, left ventricular systolic function and severity of valve obstructions. When the heart disease is severe (e.g. severe mitral stenosis), balloon valvuloplasty or mitral valve surgery should be considered before pregnancy. If a woman with heart disease presents already pregnant, her cardiac status and medication should be evaluated and should be treated by a specialized team of cardiologist, obstetricians and anaesthesiologist. A detailed plan for her pregnancy and delivery should be made early in pregnancy and changed if cardiac deterioration occurs. Table 20.2 Recurrence risks of congenital heart disease in offspring* Type of heart disease Total risk (%) Mother affected (%) Father affected (%) Acyanotic congenital heart disease Atrial septal defect Ventricular septal defect Atrioventricular septal defect Patent ductus arteriosus Pulmonary stenosis Left ventricular obstruction Coarctation of aorta 3 –5 4 –8 10 –15 3–4 4 11–15 6 4.5– 6 6–9.5 7.5–15 4 6.5 10 –11 4 1.5 2–2.5 1–7 2 2 3 2.5 Cyanotic congenital heart disease Tetralogy of Fallot Transposition of great vessels 2.2–3.1 0.5 2.5 1.5 Mendelian disorders Holt–Oram syndrome Noonan’s syndrome Marfan’s syndrome 50 50 50 50 50 50 50 50 50 *Based on multiple studies [36 – 40]. TETC20 12/2/05 9:41 Page 611 Pregnancy and Heart Disease Maternal low-risk conditions All the conditions which benefit from the decrease in systemic vascular resistance that occurs during pregnancy are very well tolerated regardless of their severity, provided that left and right ventricular function is not impaired. These conditions include mild and moderate valve regurgitation [16,17] and small–moderate left-toright shunts without pulmonary hypertension. Mild, moderate and moderately severe right ventricular outflow tract obstruction are very well tolerated during pregnancy, as shown by previous series in which no deaths and a low incidence of complications have been reported [18]. However, the severe form of pulmonary valve stenosis and moderate stenosis with impaired right ventricular function should be treated before conception. Percutaneous pulmonary balloon valvuloplasty during pregnancy may be indicated in very severe (gradient suprasystemic) and/or symptomatic cases. A few successful cases have been reported [16] (Fig. 20.2). Stenting of pulmonary arteries can also be performed successfully during pregnancy. Mild left ventricular outflow tract obstruction is well tolerated during pregnancy even if pressure gradient doubles due to the increased cardiac output (Fig. 20.3) [18], whereas the moderate form must be followed carefully due to the possibility of rapid clinical deterioration. Aortic coarctation carries a small risk of dissection [19] and should be corrected before pregnancy. During pregnancy women with mild coarctation should undergo close monitoring of blood pressure and treatment with a beta-blocking agent will be indicated if hypertension develops [20]. Percutaneous balloon angioplasty should be avoided in coarctation during pregnancy because of the risk of aortic dissection or rupture [21]. Because of the risk of restenosis after repair of coarctation in childhood, all women with a history of operated coarctation who consider pregnancy should be assessed. In patients who have undergone previous successful surgical repair without mechanical heart valve implantation (tetralogy of Fallot, atrial repair for transposition of the great arteries [22], atrial and ventricular defects, aortic coarctation [19,20]), pregnancy is well tolerated if normal exercise tolerance, good functional status and normal ventricular function are present. Close follow-up is recommended (cardiac assessment every trimester). Although women with some conditions are at low risk during pregnancy, other conditions can worsen after delivery, including intra-atrial repair of transposition of the great arteries [22,23], Ebstein’s anomaly [24], mild valve stenosis and mild cardiomyopathies (ejection fraction 45–55%). For example, 25% of women with intra-atrial repair of transposition experience deterioration of their right ventricular function during pregnancy and most of them do not recover to the baseline level [25]. Figure 20.2 (A,B) Echocardiographic (A, parasternal short-axis view; B, continous-wave Doppler) and (C) angiographic image of a pregnant woman with severe pulmonic stenosis. Peak gradient was 144 mmHg. She was treated with balloon dilatation during pregnancy (D), the peak gradient decreasing to 40 mmHg after dilatation (E). RV, right ventricle; LV, left ventricle; PA, pulmonary artery; Vmax, maximal velocity (m/s) measured over the pulmonic valve. (Continued p. 612) 611 TETC20 12/2/05 9:41 Page 612 612 Chapter 20 C D E Figure 20.2 (cont’d ). Maternal high-risk conditions Previous studies have recognized that prior cardiac events or arrhythmias, poor functional class, cyanosis, left heart obstruction and left ventricular systolic dysfunction independently predict maternal cardiac complications [26,27]. There are some specific conditions at particular risk during pregnancy. Pulmonary hypertension A 30–50% maternal mortality risk is still reported in patients with severe pulmonary vascular disease, either with septal defects (Eisenmenger’s syndrome) or without [28,29], and fetal loss is of a similar magnitude. Systemic vasodilatation increases the right-to-left shunt and decreases pulmonary output, leading to a low-output status. Death occurs in the last months of pregnancy or in the first few days after delivery because of pulmon- TETC20 12/2/05 9:41 Page 613 Pregnancy and Heart Disease 613 A B Figure 20.3 Echocardiographic continous-wave Doppler images of a severe aortic stenosis in a pregnant woman. The peak gradient changed from 45 mmHg before pregnancy (A) to 85 mmHg after 18 weeks of pregnancy (B). ary hypertensive crises, mostly due to fibrinoid necrosis, rarely to pulmonary thrombosis. It can happen even in patients with little or no disability before or during pregnancy. The level of pulmonary hypertension that should be considered at risk is around 70 mmHg systolic or > 30 mmHg mean pulmonary pressure. Even moderate forms of pulmonary vascular disease can worsen during pregnancy as a result of the decrease in systemic resistance and of overload of the right ventricle. Termination of pregnancy is advisable. If pregnancy continues, patients should restrict their physical activity, avoid the supine position and take subcutaneous heparin as prophylaxis against thromboembolism [17,30]. Intravenous or pulmonary infusion of prostacyclin (epoprostenol) has been occasionally used to decrease pulmonary pressure during delivery and postpartum in order to manage pulmonary hypertensive crises [31,32]. Further evaluation is needed before using new drugs such as the oral phosphodiesterase inhibitor sildenafil and the endothelin receptor antagonist bosentan during pregnancy [33,34]. Invasive monitoring during labour and delivery is recommended. Severe left ventricular tract obstruction Congenital, most often bicuspid, aortic valve stenosis is rare during pregnancy because patients have usually had percutaneous or surgical valvuloplasty in childhood or before conception. Women with an aortic valve area < 1.0 cm2 should be discouraged from conceiving before treatment especially when they are symptomatic. In severe aortic stenosis, the fixed resistance may not be able to accommodate the increased cardiac output that occurs during pregnancy. An increase in both gradient and left ventricular end-diastolic pressure is induced and can cause heart failure, low output and reduction in uteroplacental perfusion. Important ECG changes of left ventricular overload in a previously normal ECG, signs of TETC20 12/2/05 9:41 Page 614 Chapter 20 A B PREGNANCY IN CYANOTIC CHD Logistic regression analysis of risk factors determinant for fetal survival RISK FACTORS Maternal disease Hb O2 saturation Age Aortic insufficiency Previous shunt PREDICTIVE POWER + + + – – + P-VALUE 0.002 <0.0001 0.0001 0.74 0.02 0.16 100 Fetal survival (%) 614 80 60 40 20 0 <85% 85–90% >90% Oxygen saturation (%) Figure 20.4 Risk factors affecting fetal survival: (A) multiple regression analysis shows that maternal disease, haemoglobin and oxygen saturation are significantly related to fetal survival; (B) fetal survival declines with the decrease in maternal oxygen saturation. heart failure and low systemic blood pressure can appear. The clinical symptoms occur at 20–24 weeks of gestation. Previous series which reported high mortality in aortic stenosis [35] were probably due to the underestimation of these signs during pregnancy as well as the lack of immediate intervention. If the fetus is viable (> 34 weeks) delivery is advised, thus restoring the pre-pregnancy haemodynamic status. If the valve is not heavily calcified and no regurgitation is present, percutaneous balloon valvotomy can be successfully performed. Five cases have been reported, with significant reduction of valve gradient, enabling the pregnancy to continue [21,36]. Surgery can be an alternative [37]. Most recent series [38] of pregnancy in aortic stenosis reported no deaths but some complications, such as pulmonary oedema and further valve deterioration requiring surgery. Cyanotic heart disease without pulmonary hypertension Cyanotic congenital heart diseases are usually corrected before pregnancy, but some inoperable or palliated cases can reach child-bearing age. The degree of maternal hypoxaemia is the most important predictor of maternal and fetal outcome (Fig. 20.4). With resting maternal blood saturation below 85%, maternal mortality is 2–5%, fetal loss is 85% and premature delivery or a low-birthweight neonate is around 50%; pregnancy should therefore be discouraged [39]. Maternal complications (heart failure, pulmonary or systemic thrombosis, supraventricular arrhythmias) occur in 30% of cases. Low-dose heparin prophylaxis is widely used and recommended, although its value has not been proved. If oxygen saturation is 85–92%, it is advisable to measure it during exercise. If there is a sudden and important drop in oxygen saturation during exercise, the pregnancy has a poor prognosis and should be discouraged. Tetralogy of Fallot is the most common cyanotic 80 72 70 Unoperated or palliated Radical correction 60 50 42 40 31 30 20 10 8,6 2 2 8 7,4 0 Maternal mortality Live born Maternal complications Offspring cardial defect Figure 20.5 Maternal and fetal complications in cyanotic patients (mostly tetralogy of Fallot) selected to receive either no operation/palliation or radical correction. Maternal complications decreased and live births increased substantially with radical correction. congenital heart defect. Comparing fetal and maternal outcome in uncorrected (i.e. cyanotic) and corrected tetralogy of Fallot, it is evident that persistent cyanosis is the most important determinant of maternal and fetal outcome (Fig. 20.5). Offspring of mothers with tetralogy of Fallot regardless of correction carry a risk of having congenital heart disease (3–10%) (see Table 20.2). Impaired left ventricular function Besides basic cardiac disease, left ventricular function is one of the main determinants of maternal and neonatal outcome. No reviews are available that indicate a cut-off value for left ventricular ejection fraction below which pregnancy is contraindicated. An echocardiographic ejection fraction > 40% with a good rise in systemic arterial pressure on exercise testing allows the continuation of pregnancy, although complications can still occur. Pregnancy termination should be advised if ejection fraction is below 40% with increased left ventricular dimensions [17]. TETC20 12/2/05 9:41 Page 615 Pregnancy and Heart Disease During pregnancy, restriction of physical activity and serial echocardiogram evaluation should be performed. Particular attention should be focused on the recognition of ventricular arrhythmias during pregnancy and after delivery, in which case 24-h Holter registration should be indicated. Particular attention should be paid when valvular disease with impaired ventricular function is present because the prognosis can be worse. Fetal high-risk conditions The fetal risks are as follows. 1 The recurrence risk of congenital malformations in the offspring of patients with major heart defects (see Table 20.2) ranges from 2 to 50% depending on the type of parental disease, with an excess in the offspring of affected women [17,40–44]. Fetal echocardiography can detect the presence of congenital heart disease and should be performed if the mother or father has congenital heart disease. 2 Abortion. 3 Intrauterine growth retardation. 4 Prematurity (Fig. 20.6). The last three complications depend on type and severity of maternal disease and poor maternal functional class (NYHA > II) [25]. Additional risk factors for adverse fetal/ neonatal events, besides the conventional obstetric ones (history of premature delivery or rupture of membranes, incompetent cervix, or caesarean section; intrauterine growth retardation, antepartum bleeding > 12 weeks’ gestation, febrile illness, or uterine/placental abnormalit- ies during present pregnancy), include maternal age > 35, multiple gestation, smoking during pregnancy and anticoagulation therapy [45]. Besides cyanotic heart disease, another condition that carries an adverse fetal outcome (45% fetal survival) is the Fontan repair for tricuspid atresia or single ventricle. In this condition the venous congestion that occurs during pregnancy leads to congestion of the intrauterine veins, with a very high incidence of spontaneous abortion. Nowadays conversion from classic Fontan to total cavopulmonary connection should be considered before pregnancy. We have to emphasize that the prematurity associated with poor maternal condition carries a high risk of newborn disabilities: 30% when the fetus is delivered at 27 weeks, 60% at 24 weeks [43]. Specific conditions Mitral valve stenosis Although its incidence is decreasing in Europe, rheumatic heart disease is still responsible for most of the cardiac complications during pregnancy. Mitral valve stenosis, nearly always of rheumatic origin, is the most common (90%) and important cardiac valvular problem during pregnancy. Mortality among pregnant women with minimal symptoms is less than 1% but in severe disease can reach 5%. Labour, delivery and the immediate puerperium appear to be the periods most at risk [17,46–48]. The pressure gradient across the narrowed mitral valve may increase greatly during pregnancy because of Figure 20.6 Creation of an atrial septal defect in utero for fetus with hypoplastic left heart syndrome and intact atrial septum. Transabdominal ultrasound image of the heart in a fetus with dilated left atrium and thin bulging atrial septum before atrial septal puncture (A), during septal puncture with Chuba needle (B) and during dilatation with 3-mm coronary angloplasty balloon (C). With permission of James E. Lock Circulation (2004) 110: 253–258. 615 TETC20 12/2/05 9:42 Page 616 616 Chapter 20 the physiological increase in heart rate (decreasing left ventricular diastolic filling time) and cardiac output. This can lead to a rise in left atrial and pulmonary wedge pressures and inability of cardiac output to increase appropriately with exercise. The onset of clinical symptoms (excessive fatigue, breathlessness on exertion, orthopnoea and nocturnal dyspnoea) may occur even in women with moderate valve stenosis or who were previously symptom-free, usually in the middle trimester. Development of atrial fibrillation could further aggravate the clinical status, leading to acute pulmonary oedema. Predictors of adverse maternal outcomes include degree of mitral valve stenosis (valve area < 1.5 cm2), NYHA functional class II or more before pregnancy and history of cardiac events [25,45]. Patients with mild valve stenosis (valve area > 1.5 cm2) who are either asymptomatic or have minor symptoms can almost always be managed with behavioural advice (restriction of salt intake, reduction of physical activity up to complete bed rest) and judicious medical therapy (diuretics to reduce pulmonary and venous congestion; beta-blockers to reduce heart rate and increase diastolic filling period). The onset of tachyarrhythmias such as atrial fibrillation or supraventricular tachycardia requires immediate treatment with cardioversion. Anticoagulation therapy is indicated in patients with atrial fibrillation. In patients with moderate mitral valve stenosis (valve area 1.1– 1.5 cm2), the different therapeutic strategies depend on the severity of symptoms before and during pregnancy and the rise in pulmonary pressure: patients who are either asymptomatic or mildly symptomatic (NYHA I–II) should undergo close follow-up with serial echocardiographic assessment (measurement of mean transmitral gradient and pulmonary artery pressure) and clinical evaluation; percutaneous balloon valvuloplasty or valve repair/replacement during pregnancy should be considered in cases with persistent symptoms despite optimal medical therapy. In patients with severe mitral valve stenosis (valve area < 1 cm2), percutaneous balloon valvuloplasty or surgical intervention before conception is indicated. In pregnant women, careful monitoring and performance of these procedures at the right time have to be planned. Percutaneous balloon valvuloplasty has been shown to be a successful and safe procedure during pregnancy in experienced centres, and has become the first-choice interventional treatment in anatomically suitable valves (young patients with non-calcified pliable valves without too much subvalvular thickening or significant mitral regurgitation) are present as a result of the significant reduction in fetal and neonatal mortality [21,49]. Labour and delivery should be planned carefully. Effective anaesthesia to minimize pain and anxiety, in addition to shortening of the second stage of labour, will decrease the haemodynamic demand on the maternal heart. Bedside ECG monitoring should be used to document rhythm disturbances. Swan–Ganz catheters are frequently used in moderate and severe mitral stenosis to monitor fluid balance. The safety of breast-feeding depends on the mother’s medication in the postpartum period. Hypertrophic cardiomyopathy Although symptoms, particularly chest pain, may increase, pregnancy is generally well tolerated and absolute maternal mortality is very low and mostly limited to high-risk patients [50,51]. Management of hypertrophic cardiomyopathy during pregnancy should not differ from that outside pregnancy. No treatment other than reassurance should be indicated in asymptomatic or mild symptomatic women, whereas in symptomatic patients beta-blockers and low-dose diuretic therapy may be indicated. Because of the negative impact of tachycardia, if supraventricular arrhythmias develop, rate-control therapy and prompt electrical cardioversion are needed. Normal vaginal delivery is safe but careful monitoring of blood loss is needed [50]. Prosthetic heart valves In women of child-bearing age, surgical valve repair is always preferable to replacement and must be performed whenever possible. If valve replacement is needed, the decision about the best type of valve prosthesis to use should take into account the woman’s age (in very young women rapid tissue valve degeneration is common), the presence of other conditions such as atrial fibrillation requiring anticoagulant therapy, and the risk of reoperation (complex anatomy, re-repeat). Bioprosthetic valve appears to be the best choice provided that the woman is informed about the structural valve deterioration associated with pregnancy and the inevitability and risk of reoperation. Previous studies have shown that pregnancy is associated with an accelerated rate of structural valve deterioration (12–60%) [49,54,55]. The incidence of prosthetic valve reoperation is 60–80% at 5–10 years follow-up, and the mortality of reoperation is 2–3.8% [54]. The management of women with bioprosthetic valves should include serial clinical evaluation and twodimensional echocardiography for early detection of valve structural deterioration, and antibiotic prophylaxis at delivery. In women with mechanical valves, pregnancy is associated with a 10% risk of prosthetic valve thrombosis and/or systemic embolization, necessitating the use of some form of anticoagulation during pregnancy throughout pregnancy. On the other hand, the use of warfarin, particularly between weeks 6 and 12 of pregnancy, is TETC20 12/2/05 9:42 Page 617 Pregnancy and Heart Disease Table 20.3 Risks of anticoagulant treatment during pregnancy reported in the literature series Fetal risk Death Embryopathy Maternal risk Death Thromboembolism Warfarin Heparin (in first trimester) Heparin throughout pregnancy Low molecular weight heparinH 30% 4–10% 24% 2% – – ? ? 1.8% 3.9% 4.2% 9–24% 7% 25% ? ? associated with fetal embryopathy (nasal hypoplasia, bone stippling and optic atrophy) that occurs in approximately 6% of cases and an increased risk of miscarriage or stillbirth (cerebral fetal haemorrhage). Because of this maternal and fetal ‘double jeopardy’, women with mechanical valves should be informed about the risks of pregnancy and the necessity for immediate pregnancy testing if menstrual periods are missed. The most appropriate anticoagulation regimen will be based on several factors: type of valve prosthesis (e.g. old generation caged-ball prosthesis vs. new bileaflet tilting disc), valve position (mitral vs. aortic), warfarin dose and the desires of prospective parents. Low-risk patients are those with an aortic new-generation valve prosthesis or those who need low doses of warfarin (≤ 5 mg) to maintain an adequate international normalized ratio (INR). The risks of anticoagulant treatment (Table 20.3) always have to be discussed with the mother. As a result of the controversial recommendations of the cardiology societies about the use of low-molecularweight heparin (LMWH), there is no consensus of opinion [47,52–57]. The management options, which await confirmation, include the following. 1 Heparin and warfarin combination: stop warfarin treatment as soon as the pregnancy test is positive. Unfractioned heparin in the first 13 weeks of pregnancy, switching to warfarin in the second trimester, continuing it until week 36 of gestation or 2 days before the planned delivery and then changing again to heparin until 4 –5 days after delivery. Heparin should be terminated at the onset of labour and re-instituted shortly (12–24 h) after delivery. During pregnancy heparin should be given subcutaneously two or three times daily and the dose adjusted to maintain the partial thromboplastin time at greater than twice control levels at all times; the monitoring should be performed at least twice weekly. In clinical practice this option is rarely chosen. 2 LMWH and warfarin combination: stop warfarin treatment as soon as the pregnancy test is positive. LMWH (nadroparin calcium or enoxaparin) in the first 13 weeks of pregnancy, switching to warfarin in the second trimester, continuing it until week 36 of gestation or 2 days before the planned delivery and then changing to heparin. LMWH should be given subcutaneously twice daily and the dose adjusted to body weight to maintain anti-Xa between 0.5 and 1.0 U/ml 4–6 h after injection. LMWH does not cross the placenta. Meticulous attention should be paid when shifting from one regimen to the other because most of the complications reported occur during these periods. These therapy changes are best followed with a hospitalized regimen. This option is probably best in high risk patients. 3 Warfarin throughout the whole of pregnancy if low doses are needed to maintain appropriate INR, with patients’ consensus. 4 LMWH throughout the whole of pregnancy, administered twice daily with dose adjusted to body weight. (This option awaits confirmation and should therefore be considered only in low-risk patients.) Marfan’s syndrome With a population incidence of 1 in 5000, Marfan’s syndrome is the most frequently encountered fibrillin-1 deficiency disorder. It is transmitted as an autosomal dominant trait and is characterized by multiorgan dysfunction, predominantly affecting the eyes, skeleton and cardiovascular system. There are two main problems in a woman with Marfan’s syndrome who is contemplating pregnancy: (1) the risk of serious maternal complications during or shortly after pregnancy and (2) the risk of recurrence in offspring. Whenever possible before starting pregnancy, any woman with Marfan’s syndrome should undergo a full clinical assessment (family history, ultrasound examination of the entire aorta, echocardiography, magnetic resonance imaging) and a careful counselling of maternal and fetal risk. The risk of aortic dissection or other serious cardiovascular complication (endocarditis or congestive heart failure) during pregnancy is 1% even in the absence of aortic root dilatation, and may further increase, reaching 10%, in the presence of poor family history, aortic root diameter > 45 mm and significant mitral or aortic valve regurgitation [25,58]. The recommendations are as follows. 617 TETC20 12/2/05 9:42 Page 618 618 Chapter 20 1 Patients with aortic root enlargement > 4.5–5 cm and aortic or mitral severe regurgitation should undergo elective surgery before pregnancy; if they refuse, they will be advised against pregnancy. 2 In patients with aortic root enlargement of 4–4.5 cm, aortic root dimension assessment with serial echocardiography (each trimester until 6 months after delivery) should be recommended. During pregnancy, physical activity should be limited and the use of beta-blocker therapy is recommended. 3 Even in patients without cardiovascular involvement, the relatively ‘small’ risk of complications should be discussed, as these can occur outside pregnancy. Clinical and echocardiographic monitoring should be performed during pregnancy and normal vaginal delivery should be conducted. Besides the risk of cardiovascular involvement, women with Marfan’s syndrome must know and accept that there is a 50% risk of their offspring having Marfan’s and that the degree of severity of the disease could be worse than that of the parent. Coronary heart disease Acute myocardial infarction rarely occurs in women of child-bearing age and has been estimated to occur in only 1 in 10 000 women during pregnancy [59]. However, with the current trend of child-bearing at an older age and the ongoing effects of cigarette smoking, diabetes and stress, the occurrence of acute myocardial infarction during pregnancy can be expected to increase. Myocardial infarction occurs mostly in multiple pregnancies and most commonly in the anterior wall. The reported maternal mortality rate, before the current practice of primary percutaneous coronary angioplasty, varies from 21 to 48%, either at the time of infarction (mostly in the third trimester) or within 2 weeks of the infarction [59,60]. The differential diagnosis of ischaemic chest pain includes haemorrhage, sickle crises, pre-eclampsia, acute pulmonary embolism and aortic dissection [61]. It is confirmed by ECG changes and increase in enzyme levels. Management includes coronary angiography with abdominal shielding. Spontaneous coronary dissection of the proximal left anterior coronary artery is the most common cause of myocardial infarction, especially in the postpartum period. Successful treatment includes coronary stenting, emergency coronary artery bypass grafting or administration of tissue plasminogen activator, as described in case reports [62]. The delivery should be postponed for at least 2 or 3 weeks after the myocardial infarction to allow adequate healing. The mode of delivery should be determined by obstetric reasons and the clinical status of the mother. Cardiac transplantation If ventricular function is normal and there are no signs of rejection, pregnancy is usually successful. The absence of rejection should be established before conception and needs to be assessed during pregnancy. Preconceptional genetic counselling is necessary depending on the indication for transplantation, such as mitochondrial myopathy or familial dilated cardiomyopathy. Management during pregnancy includes monitoring left ventricular function and preventing complications such as hypertension, infection, preterm labour, intrauterine growth restriction and pre-eclampsia [61,63,64]. The choice of delivery mode is based on obstetric indications. Cardiovascular treatment during pregnancy Treatment in pregnancy is not based on randomized trials but on limited data from case reports (successes tend to be reported), observational studies and clinical individual experience. The safety of both mother and fetus has to be taken into account because treatment for one can have adverse effects on the other. Pregnant patients with heart disease and their close relatives should receive general advice such as limitation of physical activity, with complete bed rest in severe cases, and salt and fluid restriction. Self-weighing should be encouraged and in the case of sudden unexpected weight gain the physician should be contacted. Other general advice includes stopping smoking and avoiding excessive alcohol intake and all unnecessary medications. Pharmacological therapy The use of any medication in pregnancy and during lactation has to consider the safety and tolerability for the fetus and infant, the physiological maternal changes and the risk–benefit ratio. In patients who are already taking cardiovascular medications, discontinuation or the switch to a ‘safer’ drug should be discussed before conception. Because of the lack of randomized trials and the fear of tragedies such as the thalidomide disaster, there is an extreme reluctance to introduce any new drugs in pregnancy. Drugs with the longest record of safety should be used as the first-choice therapy [65,66]. However, the fear of ‘unpredictable’ complications must not overcome the correct use of drug treatment in pregnancy, because most of the drugs used to treat heart disease can be prescribed safely during pregnancy. TETC20 12/2/05 9:42 Page 619 Pregnancy and Heart Disease The effective plasma concentration of drugs varies during pregnancy. For example, the progesterone-induced reduction in gastrointestinal motility and the estrogeninduced increase in gastric secretion may result in altered drug absorption. Intravascular volume is increased during pregnancy, resulting in enhanced volume distribution and lower serum concentrations that may require an increase in the loading dose. Serum protein concentration falls during pregnancy, causing a reduction in protein binding and an increase in the non-protein-bound fraction. Increases in renal blood flow and glomerular filtration rate may augment drug clearance. The transplacental transfer of drugs depends on liposolubility or hydrosolubility and molecular weight of the drug, the pH of maternal and fetal fluids, the link with carrier protein and the gradient between maternal and fetal concentration [67,68]. Table 20.4 categorizes drugs according to the reliability of evidence of fetal risk and the potential risk–benefit ratio [65–81]. Therapy of heart failure Diuretics are the first drugs to be employed in order to reduce hypervolaemia in patients with severe symptomatic congestive heart failure not responding to water and salt restriction. Diuretics are not recommended for management of pedal oedema or prophylaxis of eclampsia. In patients already receiving diuretics, the therapy should be continued during pregnancy and the peripartum period independently of the presence of mild hypotension. Although furosemide crosses the placental barrier, it is the drug of choice because no teratogenic or cardiovascular fetal effects have been described. Collateral effects to be controlled are hypovolaemia and hypokalaemia. Particular caution should be taken in cyanotic patients because haemoconcentration can cause thrombosis. No adverse events have been reported in patients treated with spironolactone, particularly indicated in cases of hypokalaemia. Thiazides are not recommended due to the reported neonatal thrombocytopenia, jaundice, hyponatraemia and bradycardia [67,68]. Angiotensin-converting enzyme (ACE) inhibitors should be withdrawn during pregnancy because of teratogenic effects. Reported complications include fetal and neonatal renal failure, oligohydramnios, intrauterine growth retardation and hypoplasia of skull bones especially in the second and third trimester [69]. There are no data available about angiotensin II receptor antagonists in pregnancy, but because their actions are similar to those of ACE inhibitors their use is contraindicated. Specific information on the safety of nitrates and sodium nitroprusside is lacking. Intravenous as well as oral nitrates have been used in a few patients for the treatment of hypertension, myocardial ischaemia and heart failure, although case reports of fetal heart decelerations have been reported. Dopamine and dobutamine can be used in low-output congestive heart failure. A few cases have been reported with no adverse effect [67–69]. However, during pregnancy with a viable fetus, fetal monitoring is advisable. The experience with digoxin is extensive and there are no reports of teratogenicity associated with its use. It is considered a preferred choice for treatment of congestive heart failure, especially when supraventricular arrhythmias and systolic dysfunction are present. Furthermore, digoxin is the first-line drug for maternal and fetal rate control in atrial fibrillation/flutter and for the treatment of fetal supraventricular tachycardias [70,71]. Because of increased renal clearance, the serum digoxin concentration may be lower and so maternal dose should be increased. In the presence of decreased renal function or concomitant administration of amiodarone, maintenance doses may require reduction. Even if higher doses are required during pregnancy, caution in changing the amount of digitalis is advised because digitalis toxicity has been associated with miscarriage and fetal death. In the third trimester, serum digoxin levels may appear falsely elevated because of the presence of digoxin-like substances interfering with radioimmunoassays. Hence, the monitoring of digoxin levels would not be helpful in guiding treatment [71]. Management of arrhythmias Pregnancy may increase the incidence of arrhythmias. Knowledge of the underlying heart disease is important for the correct treatment. Most of the antiarrhythmic drugs can be prescribed safely in pregnancy but an attempt to recognize a correctable cause should be undertaken before starting therapy. All antiarrhythmic drugs cross the placental barrier and their potentially toxic effect on the fetus should be taken into consideration, particularly during the first weeks of pregnancy [71]. maternal tachyarrhythmias Ectopic beats are present in one-third of pregnant women but are generally benign and well tolerated. No treatment other than reassurance and correction/elimination of potential stimulants are indicated. An increased risk of new-onset, and exacerbation of, supraventricular tachycardia during pregnancy has been reported (3%), while ventricular tachycardia is rare. When dysrhythmias such as atrial fibrillation or flutter are present during pregnancy, an underlying cause should be considered. Electrical cardioversion is the treatment of choice for all drug-refractory maternal arrhythmias or those 619 TETC20 12/2/05 9:42 Page 620 620 Chapter 20 Table 20.4 Cardiovascular drugs during pregnancy* Drug Use during pregnancy Antiarrhythmic agents Adenosine First-line treatment: paroxysmal supraventricular tachycardia Amiodarone Refractory maternal and fetal arrhythmias Maternal arrhythmias in presence of impaired left ventricular function Beta-blockers Control ventricular rate in atrial (atenolol, fibrillation propranolol, Second-line treatment of maternal metoprolol) supraventricular arrhythmias Prophylactic therapy for supraventricular and ventricular tachycardias Digoxin (see heart failure) Flecainide Second-line therapy for maternal and fetal supraventricular arrhythmias Lidocaine Maternal ventricular arrhythmias Local anaesthesia Propafenone Second-line therapy for maternal supraventricular arrhythmias Sotalol Second-line therapy for maternal supraventricular arrhythmias Fetal tachycardia Verapamil Second-line therapy for maternal supraventricular arrhythmias Heart failure therapy ACE inhibitors Not recommended Angiotensin II Not recommended receptor antagonists Digoxin Prophylactic therapy for supraventricular tachycardias Control of ventricular rate in atrial fibrillation Fetal tachycardia Heart failure Loop diuretics Severe symptomatic congestive heart (furosemide) failure Sparing diuretics Congestive heart failure and (spironolactone) hypokalaemia Nitrates Myocardial ischaemia Heart failure Hypertension Hypertensive disease therapy Prophylactic treatment in women with historical risk factors Aspirin Reduces the risk of perinatal death and pre-eclampsia Calcium Positive impact on maternal and fetal supplementation morbidity needs to be confirmed Magnesium sulphate Reduces the risk of eclampsia in women with severe pre-eclampsia Severe hypertension Hydralazine Labetalol Nifedipine Nitroprusside Second-line therapy First-line therapy First-line therapy Second-line therapy *Based on multiple studies [57–73]. Adverse fetal or neonatal effects Breast-feeding No teratogenicity or other adverse effects Intrauterine growth retardation, premature birth, fetal hypothyroidism No teratogenicity Fetal bradycardia, hypoglycaemia, premature labour and metabolic abnormalities Intrauterine growth retardation? Short half-life makes a problem unlikely Secreted in maternal milk so not recommended No reports of teratogenicity Limited data Fetal bradycardia, central nervous system toxicity Limited data Compatible Limited data Fetal bradycardia, intrauterine growth retardation Limited data Maternal hypotension and subsequent fetal hypoperfusion Limited data Teratogenic effects Limited data Compatible Limited data No reports of teratogenicity Compatible No teratogenic or cardiovascular fetal effects No teratogenic effects Compatible Fetal heart deceleration, maternal hypotension and subsequent fetal hypoperfusion Limited data Compatible Haemorrhage, prolongation of labour Limited data Limited data Neonatal bradycardia Neonatal bradycardia Fetal distress Thiocyanate poisoning Compatible Limited data Limited data Limited data TETC20 12/2/05 9:42 Page 621 Pregnancy and Heart Disease causing haemodynamic compromise and can be performed safely at any time during pregnancy. Paroxysmal supraventricular tachycardias are usually well tolerated and require active therapy only if very frequent or long-lasting or with haemodynamic instability. Vagal manoeuvre should be tried first and, if ineffective, intravenous adenosine would be the first-choice drug. Maternal effects may include facial flushing, headache, dyspnoea and nausea. Adenosine crosses the placenta but no adverse fetal effects have been described. Secondline drugs include beta-blocking agents or propafenone. Intravenous verapamil can be used but maternal hypotension, heart failure and inhibition of labour have been reported. If prophylactic drug therapy is needed, then β1 receptor blockers or digoxin are the first choice [69,70]. Atrial fibrillation and flutter are rare in pregnancy and often secondary to congenital or valvular heart disease. Therapy includes ventricular rate control using digoxin or beta-blocking agents and conversion to sinus rhythm using propafenone or amiodarone (termination of atrial episodes should be attempted in order to avoid anticoagulation therapy). Ventricular tachycardia during pregnancy is rare in healthy women without organic disease but it can occur when ventricular scars are present (e.g. tetralogy of Fallot). Beta-blockers are the first-line therapy when ventricular function is preserved. Some forms of non-sustained ventricular tachycardia in normal hearts respond well to verapamil. If ventricular function is impaired, amiodarone is the only option. Chronic administration of amiodarone can have adverse effects on the mother in 3–5% of cases, including thyroid malfunction, photosensitivity and corneal deposition. In the fetus, long-term treatment with amiodarone can cause neonatal hypothyroidism [71,72], which is however reversible. Although catheter ablation has been performed in a pregnant patient, it should be recommended only in patients with drug-refractory, poorly tolerated or lifethreatening arrhythmias [68]. The presence of an implantable cardioverter–defibrillator should not be considered a contraindication to pregnancy [73], but implantation during pregnancy has never been reported in the literature. maternal bradyarrhythmias Compared with the tachyarrhythmias, bradyarrhythmias are uncommon, but when they occur are usually well tolerated. Management should not be influenced by pregnancy. Temporary or permanent pacemaker, if required, can be implanted at any stage of pregnancy, although treatment is generally not indicated unless the conduction abnormality causes symptoms. Women with congenital complete heart block, as previously reported, can accomplish an uneventful and successful pregnancy [74] with or without a pacemaker. fetal arrhythmias Fetal tachycardia, defined as a heart rate greater than 180 b.p.m., is a condition that occurs in approximately 0.4–0.6% of all pregnancies, and may cause non-immune fetal hydrops and lead to fetal morbidity and mortality. Maternal full-dose digoxin is the first-line antiarrhythmic agent in non-hydropic fetuses, while verapamil and beta-blocking agents are second-line therapy. In drugrefractory fetal tachycardia, particularly if accompanied by hydrops fetalis or ventricular dysfunction, amiodarone represents a safe and effective option [75]. Sotalol should be considered a valuable treatment option for fetal atrial fibrillation, which is extremely rare [76]. Prophylaxis of endocarditis As in the non-pregnant state, antibiotic prophylaxis is indicated before undergoing a procedure likely to cause bacteraemia. Since the incidence of bacteraemia following vaginal delivery has been reported to be low (0–5%), routine antibiotic prophylaxis for uncomplicated vaginal delivery or primary (or planned) caesarean section in women with heart disease is not recommended [17,46,77]. However, the high morbidity and mortality associated with cardiac infection, the risk of unpredictable complications and the relatively safety of antibiotic prophylaxis in patients who are already receiving it should lead to consideration of antibiotic prophylaxis in all high-risk cardiac conditions. Antibiotic therapy should be administered 30 min before caesarean section or at the beginning of spontaneous delivery. Percutaneous therapy Over the last 20 years, interventional cardiology has emerged as a new therapeutic tool and as an effective alternative to surgical therapy in several cardiac diseases, such as valve stenosis and coronary artery disease [21]. Cardiac catheterization in the pregnant patient carries the risk of fetal radiation exposure. The effects of radiation on the fetus depend on the radiation dose and the gestational age at which exposure occurs. As previously reported, the maximum permissible dose of radiation to the pregnant woman has been set at 5 mGy. During cardiac catheterization the mean radiation exposure to the unshielded abdomen is 1.5 mGy, and less than 20% of this reaches the fetus because of tissue attenuation. Shielding the gravid uterus from direct radiation, shortening fluoroscopic time and delaying the procedure until at least the completion of the period of major organogenesis (> 12 weeks after menses) will minimize radiation exposure. With these provisions, cardiac catheterization and interventional procedures during 621 TETC20 12/2/05 9:42 Page 622 622 Chapter 20 pregnancy are safe for the fetus but should be considered only in patients not manageable with medical therapy (see Fig. 20.2). Cardiac surgery Open heart surgery can be performed during pregnancy, with the same risk to the mother as outside pregnancy but with a high incidence of fetal death (20–33%). The best period to perform surgery is early in the second trimester because in the first trimester it may cause abortion and later in the third trimester premature labour. The poor fetal outcome is due to non-pulsatile blood flow and hypotension associated with cardiopulmonary bypass that can adversely affect placental blood flow. Cardiopulmonary bypass in pregnancy must be performed at high flow and high pressure, in normothermia, with the shortest possible cross-clamping time. Personal perspective Pregnancy is a part of a woman’s life and not a disease and most of the time is surprisingly well tolerated in patients with mild or moderate heart disease. The important rise in cardiac output that occurs particularly in the second and third trimesters of pregnancy is well balanced by the decrease in peripheral vascular resistance. Pregnancy continuation should be encouraged in the majority of cases, although patients with a severe degree of mitral or aortic valve stenosis remain particularly at risk. Pregnancy must be followed by an experienced team, particularly in the third trimester and during and after delivery. The panorama of heart disease in women of child-bearing age has changed and will change further. The profile of the cases at risk has become different: pulmonary hypertension and cyanotic heart disease have become rare because of early correction during infancy; palliated or corrected forms of congenital heart disease with residual defects, valvular heart disease in immigrants and cardiomyopathies with or without coronary artery disease in older women have become more frequent. Multiple other factors can increase the risk during pregnancy in women with heart disease. Older age at pregnancy, smoking habits and twin or triple pregnancy References 1 Lupton M, Otehng-Ntim E, Ayida G et al. Cardiac disease in pregnancy. Curr Opin Obstet Gynecol 2002; 14: 137–143. 2 Thilen U, Olsson SB. Pregnancy and heart disease: a review. Eur J Obstet Gynecol Reprod Biol 1997; 75: 43 –50. 3 Presbitero P, Contrafatto I. Pregnancy and the heart. In: Crawford MH, Dimarco JP (eds.). Cardiology, 1999. London: McGraw-Hill, pp. 530 –543. 4 Robson SC, Hunter S, Boys RJ et al. Serial study of factors influencing changes in cardiac output during human pregnancy. Am J Physiol 1989; 256: H1060 –H1065. secondary to frequent in vitro fertilization are much more common and have to be taken into consideration when assessing the risk. Heart failure secondary to impaired left or right ventricular function has become a common complication in this setting and its early recognition and treatment is mandatory. Correction of residual defects or aortic or mitral valve disease, particularly stenotic valves even with moderate degrees of stenosis, should be considered before pregnancy. Percutaneous procedures or minimally invasive surgical repair can today be performed in these young women with low rates of complications, making it easier to accomplish pregnancy without problems. Rest is the first step in all patients at risk. Heart failure should be managed according to conventional guidelines, except for the use of ACE inhibitors because of their known fetal toxicity. Particular attention should be paid to fluid retention in the immediate postpartum period. Interventional procedures or heart surgery, particularly during the second and third trimesters, can be done with acceptable risks for mother and fetus. From the surgical standpoint, short pump runs with high flow rates are essential criteria, ensuring low levels of fetal loss. 5 Letsky E. Haematological changes during pregnancy. In: Oakley C (ed.). Heart Disease in Pregnancy, 1997. London: BMJ Publishing Group, pp. 19 –51. 6 Van Oppen ACA, Van Der Tweel I, Alsbach GPJ et al. A longitudinal study of maternal hemodynamics during normal pregnancy. Obstet Gynecol 1996; 88: 40–46. 7 Doig JC, McComb JM, Reid DS. Incessant atrial tachycardia accelerated by pregnancy. Br Heart J 1992; 67: 266 –268. 8 Granger JP. Maternal and fetal adaptations during pregnancy: lessons in regulatory and integrative physiology. Am J Physiol 2002; 283: R1289–R1292. 9 Robson SC, Dunlop W, Boys RJ et al. Cardiac output during labour. Br Med J 1987; 295: 1169 –1172. TETC20 12/2/05 9:42 Page 623 Pregnancy and Heart Disease 10 Elkayam U. Pregnancy and cardiovascular disease. In: Braunwald E (ed.). Heart Disease. A Textbook of Cardiovascular Medicine, 1997, 5th edn. Philadelphia: WB Saunders, pp. 1843 –1864. 11 Cole PL, Sutton MJ. Cardiovascular physiology of pregnancy. In: Douglas PS (ed.). Cardiovascular Health and Disease in Women, 1993. Philadelphia: WB Saunders, pp. 305–328. 12 Mishra M, Chambers JB, Jakson G. Murmurs in pregnancy: an audit of echocardiography. Br Med J 1992; 304: 1413–1414. 13 Wenger N, Hurst J, Strozier V. Electrocardiographic changes in pregnancy. Am J Cardiol 1964; 13: 774 –778. 14 Mesa A, Jessurun C, Hernandez A et al. Left ventricular diastolic function in normal human pregnancy. Circulation 1999; 99: 511–517. 15 Campos O, Andrade JL, Bocanegra J et al. Physiologic multivalvular regurgitation during pregnancy: a longitudinal Doppler echocardiographic study. Int J Cardiol 1993; 40: 265 –272. 16 Nihoyannopoulos P. Cardiovascular examination in pregnancy and the approach to diagnosis of cardiac disorder. In: Oakley C (ed.). Heart Disease in Pregnancy, 1997. London: BMJ Publishing Group. 17 Oakley C, Child A, Lung B et al. Expert consensus document on management of cardiovascular diseases during pregnancy: The Task force on Management of Cardiovascular Diseases During Pregnancy of the European Society of Cardiology. Eur Heart J 2003; 24: 761–781. 18 Oakley C. Acyanotic congenital heart disease. In: Oakley C (ed.). Heart Disease in Pregnancy, 1997 London: BMJ Publishing Group. 19 Deal K, Wooley CF. Coarctation of the aorta and pregnancy. Ann Intern Med 1973; 78: 706 –710. 20 Beauchesne LM, Connolly HM, Ammash NM et al. Coarctation of the aorta: outcome in pregnancy. J Am Coll Cardiol 2001; 38: 1728–1733. 21 Presbitero P, Prever SB, Brusca A. Interventional cardiology in pregnancy. Eur Heart J 1996; 17: 182 –188. 22 Genoni M, Jenni R, Hoerstrup SP et al. Pregnancy after atrial repair for transposition of the great arteries. Heart 1999; 81: 276–277. 23 Presbitero P, Somerville J, Rabajoli F et al. Corrected transposition of the great arteries without associated defects in adult patients: clinical profile and follow up. Br Heart J 1995; 53: 357–358. 24 Connolly HM, Warnes CA. Ebstein’s anomaly: outcome of pregnancy. J Am Coll Cardiol 1994; 23: 1194 –1198. 25 Guèdes A, Mercier LA, Leduc L et al. Impact of pregnancy on the systemic right ventricle after Mustard operation for transposition of the great arteries. J Am Coll Cardiol 2004; 44: 433 – 437. 26 Siu SC, Sermer M, Colman JM et al. Prospective multicenter study of pregnancy outcomes in women with heart disease. Circulation 2001; 104: 515 –521. 27 Siu SC, Sermer M, Harrison D et al. Risk and predictors for pregnancy related complications in women with heart disease. Circulation 1997; 96: 2789 –2794. 28 Weiss BM, Zemp L, Seifert B et al. Outcome of pulmonary vascular disease in pregnancy: a systematic overview from 1978 through 1996. J Am Coll Cardiol 1998; 31: 1650–1657. 29 Yentis SM, Steer PJ, Plaat F et al. Eisenmenger’s syndrome in pregnancy: maternal and fetal mortality in the 1990s. Br J Obstet Gynaecol 1998; 105: 921–922. 30 Oakley C. Pulmonary hypertension. In: Oakley C (ed.). Heart Disease in Pregnancy, 1997. London: BMJ Publishing Group pp. 97–111. 31 Geohas C, McLaughlin V. Successful management of pregnancy in a patient with Eisenmenger syndrome with epoprostenol. Chest 2003; 124: 1170 –1173. 32 Bildirici I, Shumway JB. Intravenous and inhaled epoprostenol for primary pulmonary hypertension during pregnancy and delivery. Obstet Gynecol 2004; 103: 1102 –1105. 33 Lacassie HJ, Germain AM, Valdes G et al. Management of Eisenmenger syndrome in pregnancy with sildenafil and l-arginine. Obstet Gynecol 2004; 103: 1118–1120. 34 Rubin LJ, Badesch DB, Barst RJ et al. Bosentan therapy for pulmonary arterial hypertension. N Engl J Med 2002; 346: 896–903. 35 Arias F, Pineda J. Aortic stenosis and pregnancy. J Reprod Med 1978; 20: 229 –232. 36 Banning AP, Pearson JF, Hall RJ. Role of balloon dilatation of the aortic valve in pregnant patients with severe aortic stenosis. Br Heart J 1993; 70: 544 –545. 37 Ben Ami M, Battino S, Rosenfeld T et al. Aortic valve replacement during pregnancy. A case report and review of the literature. Acta Obstet Gynecol Scand 1990; 69: 651–653. 38 Silversides CK, Colman JM, Sermer M et al. Early and intermediate-term outcomes of pregnancy with congenital aortic stenosis. Am J Cardiol 2003; 91: 1386–1389. 39 Presbitero P, Somerville J, Stone S et al. Pregnancy in cyanotic congenital heart disease. Outcome of mother and fetus. Circulation 1994; 89: 2673 –2676. 40 Burn J, Brennan P, Little J et al. Recurrence risks in offspring of adults with major heart defects: results from first cohort of British collaborative study. Lancet 1998; 351: 311–316. 41 Deanfield J, Thaulow E, Warnes C et al. Management of grown-up congenital heart disease. Eur Heart J 2003: 24: 1035 –1084. 42 Nora JJ, Berg K, Nora AH. Cardiovascular Diseases. Genetics, Epidemiology and Prevention, 1991. New York: Oxford University Press. 43 Holder SE. Genetic counselling. In: Oakley C (ed.). Heart Disease in Pregnancy, 1997. London: BMJ Publishing Group, pp. 401–411. 44 Digilio MC, Casey B, Toscano A et al. Complete transposition of the great arteries: patterns of congenital heart disease in familial precurrence. Circulation 2001; 104: 2809 –2814. 45 Siu SC, Colman JM, Sorensen S et al. Adverse neonatal and cardiac outcome are more common in pregnant women with cardiac disease. Circulation 2002; 105: 2178–2184. 46 Bonow RO, Carabello B, de Leon AC. ACC/AHA guidelines for management of patients with valvular heart disease: a 623 TETC20 12/2/05 9:42 Page 624 624 Chapter 20 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. J Am Coll Cardiol 1998; 32: 1486 –1588. Reimold SC, Rutherford MB. Valvular heart disease in pregnancy. N Engl J Med 2003; 349: 52 – 59. Silversides CK, Colman JM, Sermer M et al. Cardiac risk in pregnant women with rheumatic mitral stenosis. Am J Cardiol 2003; 91: 1382 –1385. de Souza JAM, Martinez EE, Ambrose JA et al. Percutaneous balloon mitral valvuloplasty in comparison with open mitral valve commissurotomy for mitral stenosis during pregnancy. J Am Coll Cardiol 2001; 37: 900 –903. Maron BJ, McKenna WJ, Vogel RA et al. ACC/AHA/ESC clinical expert consensus document on hypertrophic cardiomyopathy. J Am Coll Cardiol 2003; 42: 1–27. Autore C, Conte MR, Piccininno M et al. Risk associated with pregnancy in hypertrophic cardiomyopathy. J Am Coll Cardiol 2002; 40: 1864 –1869. Hung L, Rahimtoola S. Prosthetic heart valves and pregnancy. Circulation 2003; 107: 1240 –1246. Hanania G, Thomas D, Michel PL et al. Pregnancy in patients with valvular prostheses: retrospective cooperative study in France (155 cases). Arch Mal Coeur Vaiss 1994; 87: 429– 437. Hirsh J, Fuster V, Ansell J et al. American Heart Association/ American College of Cardiology Foundation Guide to warfarin therapy. Circulation 2003; 107: 1692 –1711. Rowan JA, McCowan LME, Raudkivi PJ et al. Enoxaparin treatment in women with mechanical heart valves during pregnancy. Am J Obstet Gynecol 2001; 185: 633 –637. Anticoagulation in Prosthetic Valves and Pregnancy Consensus Report Panel and Scientific Roundtable Discussion. Anticoagulation and enoxaparin use in patients with prosthetic heart valves and/or pregnancy. Clinical Cardiology Consensus Reports Atlanta, 2002, pp. 1–20. Ginsberg JS, Greer I, Hirsh J. Use of antithrombotic agents during pregnancy. Chest 2001; 119 (suppl.): 122 –131. Child AH. Management of pregnancy in Marfan syndrome, Ehlers–Danlos syndrome, and other heritable connective tissue disorders. In: Oakley C (ed.). Heart Disease in Pregnancy, 1997. London: BMJ Publishing Group, pp. 153–162. Roth A, Elkayam U. Acute myocardial infarction associated with pregnancy. Ann Intern Med 1996; 125: 751–762. Ascarelli MH, Grider AR, Hsu HW. Acute myocardial infarction during pregnancy managed with immediate percutaneous transluminal coronary angioplasty. Obstet Gynecol 1996; 88: 655 – 657. Ray P, Murphy GJ, Shutt LE. Recognition and management of maternal cardiac disease in pregnancy. Br J Anaesth 2004; 93: 428 – 439. Collins JS, Bossone E, Eagle KA et al. Asymptomatic coronary artery disease in a pregnant patient. A case report and review of literature. Herz 2002; 27: 548 –554. Cowan SW, Coscia LC, Philips LZ et al. Pregnancy outcomes in female heart and heart–lung transplant recipients. Transplant Proc 2002; 34: 1855 –1856. Baron O, Hubaut J, Galetta D et al. Pregnancy and 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 heart–lung transplantation. J Heart Lung Transplant 2002; 21: 914 –917. Brigs GC, Freeman RK, Yaffe SJ. Drugs in Pregnancy and Lactation: A Reference Guide to Fetal and Neonatal Risk, 1998. Baltimore: Williams & Wilkins. Bloomfield TH, Hawkins DF. The effect of drugs on the human fetus. In Setchell M, Ginsberg J (eds). Scientific Foundations of Obstetrics and Gynaecology, 1991. Oxford: Butterworth Heinemann, pp. 320 –336. Elkayam U. Pregnancy and cardiovascular disease. In: Braunwald E (ed.). Heart Disease. A Textbook of Cardiovascular Medicine, 1997, 5th edn. Philadelphia: WB Saunders, pp. 1843 –1864. Opasich C, Russo A, Colombo E et al. Your cardiac patient wants to become a mother. Risk considerations and advice. Ital Heart J 2000; 1: 667–673. Buttar HS. An overview of the influence of ACE inhibitors on fetal–placental circulation and perinatal development. Mol Cell Biochem 1997; 176: 61–71. Blomstrom-Lundquist C, Scheiman MM, Aliot EM et al. ACC/AHA/ESC Guidelines for the management of patients with supraventricular arrhythmias. Circulation 2003; 108: 1871–1909. Tan HL, Lie KI. Treatment of tachyarrhythmias during pregnancy and lactation. Eur Heart J 2001; 22: 458–464. Magee LA, Downar E, Sevner M et al. Pregnancy outcome after gestational exposure to amiodarone in Canada. Am J Obstet Gynecol 1995; 172: 1307–1311. Natale A, Davidson T, Geiger MJ et al. Implantable cardioverter defibrillators and pregnancy. A safe combination? Circulation 1997; 96: 2808–2812. Gowda RM, Khan IA, Mehta NJ et al. Cardiac arrhythmias in pregnancy: clinical and therapeutic considerations. Int J Cardiol 2003; 88: 129 –133. Strasburger JF, Cuneo BF, Michon MM et al. Amiodarone therapy for drug-refractory fetal tachycardia. Circulation 2004; 109: 375 –379. Oudijk MA, Ruskamp JM, Ververs T et al. Treatment of fetal tachycardia with sotalol: transplacental pharmacokinetics and pharmacodynamics. J Am Coll Cardiol 2003; 42: 765 –770. Sugrue D, Troy P, McDonald D et al. Antibiotic prophylaxis against infective endocarditis: recommendations by the American Heart Association. JAMA 1997; 277: 1794 –1801. Montan S. Drugs used in hypertensive diseases in pregnancy. Curr Opin Obstet Gynecol 2004; 16: 111–115. Magee LA, Cham C, Waterman EJ et al. Hydralazine for treatment of severe hypertension in pregnancy: metaanalysis. Br Med J 2003; 327: 955 –965. Chiaffarino F, Parazzini F, Paladini D et al. A small randomised trial of low-dose aspirin in women at high risk of pre-eclampsia. Eur J Obstet Gynecol Reprod Biol 2004; 112: 142 –144. Coomarasamy A, Honest H, Papaioannou S et al. Aspirin for prevention of preeclampsia in women with historical risk factors: a systematic review. Obstet Gynecol 2003; 101: 1319 –1332.