Section 4: Antenatal Care: Specifi c Maternal Conditions
Aortic stenosis: Introduction and
• there is no exercise-induced systolic pulmonary artery hypertension (pulmonary artery pressure
<60 mmHg) .
It follows that patients with severe isolated aortic stenosis should be considered for prepregnancy aortic valve replacement if they have [ 5 ]:
• symptoms at rest or on exercise
• left ventricular dysfunction (e.g. ejection fraction
<50%) at rest
• no increase in left ventricular ejection fraction during exercise
• ECG changes at rest or during exercise
• a failure to increase, or a fall in, blood pressure during exercise
• an exercise-induced rise in mean aortic valve gradient of ≥20 mmHg
• exercise-induced systolic pulmonary artery hypertension ≥60 mmHg .
Women with critical aortic stenosis (valve area
<0.75 cm 2 ) should be off ered prepregnancy aortic valve replacement regardless of symptoms or other parame- ters, since decompensation during pregnancy is highly probable .
Antenatal monitoring
Termination of pregnancy should be discussed as an option for all women with critical aortic stenosis or for women with severe aortic stenosis and adverse prog- nostic markers, depending on gestational age at diag- nosis/presentation and the wishes and views of the mother.
Signs and symptoms of decompensation during pregnancy include:
• progressive dyspnea and or tachycardia beyond what would normally be expected during pregnancy
• new-onset angina
• presyncope (light-headedness) on exertion
• pulmonary edema and or syncope.
New ischemic ECG changes may also indicate decom- pensation . During pregnancy, the Doppler velocity across the stenotic aortic valve should increase as the cardiac output increases. A fall in the Doppler-derived echocardiography aortic valve gradient suggests that left ventricular function is impaired, and this should be verifi ed by echocardiography. A fall in aortic valve velocity may thus be a sign of a failing left ventricle and impending cardiovascular collapse—delivery or aortic
valve intervention should be considered as a matter of urgency .
Medical management
As with mitral stenosis, medical treatment is aimed at reducing the heart rate to allow time for left ventricu- lar ejection and coronary fi lling. Bed rest with oxygen therapy and, if there is no left ventricular dysfunc- tion or pulmonary edema, beta-blockade may allow the pregnancy to progress until the fetus can be safely delivered. However, medical management of decom- pensating severe aortic stenosis in a pregnant patient is unlikely to be suffi cient and delivery with or without aortic valve intervention should not be delayed .
Intervention
If the woman’s condition deteriorates and the gesta- tional age does not allow for delivery of a baby with a reasonable prognosis, then intervention without inter- rupting the pregnancy can be considered. Th e options are balloon aortic valvotomy, surgical aortic valvotomy, or aortic valve replacement. Compared with the exten- sive literature on balloon valvotomy for mitral stenosis, there are only a few case reports of balloon aortic val- votomy during pregnancy: this probably refl ects both the rarity of decompensated severe aortic stenosis and, perhaps, inferior results of balloon aortic valvotomy in adults.[ 16 ] Th e latter is usually a palliative procedure in adults, and may be seen as a bridge to aortic valve replacement, merely allowing suffi cient relief of the stenosis to permit the pregnancy to progress. Careful echocardiographic assessment is needed to assess the suitability of the valve for balloon valvotomy since it may result in poorly tolerated severe aortic regurgita- tion or aortic rupture requiring higher-risk emergency surgery .
Cardiopulmonary bypass surgery during pregnancy
If surgery for aortic stenosis during pregnancy is neces- sary, valve replacement is likely to be necessary because surgical valvotomy (as with balloon valvotomy) may not result in adequate relief of stenosis. Th e additional advantage of aortic valve replacement is that it provides relief of stenosis with valve competence.
Cardiopulmonary bypass in pregnancy carries a high risk of maternal and fetal demise. Th e risk of mater- nal death is up to 15%, whereas the risk of fetal death
Section 4: Antenatal Care: Specifi c Maternal Conditions
is between 19% and 33%.[ 17 – 19 ] A number of factors contribute to the high maternal or fetal risk. Operations may need to be performed as an emergency with a hemo- dynamically unstable woman at a time when the most experienced team members may be unavailable. Th e hormonal eff ects of pregnancy render maternal tissues more elastic and friable than in the nonpregnant state, thus contributing to additional maternal risk. While the woman is on cardiopulmonary bypass there is a risk of heparin-induced placental bleeding . Low-pressure, nonpulsatile perfusion during bypass reduces placen- tal perfusion. Pulsatile pressure is thought to reduce uterine contractions by inducing nitric oxide release.
Cardiopulmonary bypass with pulsatile perfusion has been reported as a possible technique to improve fetal outcome [ 20 ]: in four cases, there was one fetal death, with no maternal deaths . For more details on cardiac interventions in pregnancy see Chapter 8 .
Labor and delivery in aortic stenosis
Vaginal birth is usually the safest mode of delivery, unless there is an obstetric indication for a cesarean section.
Slow and incremental low-dose epidural analgesia is appropriate, taking care to avoid vasodilatation.[ 21 , 22 ] Women with severe aortic stenosis should be monitored invasively (with an arterial line and external pressure transducer, and central venous access) and careful fl uid balance maintained. Monitoring in a high dependency unit should be continued for 24–48 h postdelivery .
References
1. Haththotuwa HR , Attygalle D , Jayatilleka AC , et al.
Maternal mortality due to cardiac disease in Sri Lanka . Int J Gynecol Obstet 2009 ; 104 : 194–8 .
2. Naidoo DP , Desai DK , Moodley J. Maternal deaths due to pre-existing cardiac disease . Cardiovasc J South Afr 2002 ; 13 : 17 – 20 .
3. Lewis G , ed. Why Mothers Die 2000–2002: Th e Sixth Report of Confi dential Enquiries into Maternal Deaths in the United Kingdom . London : RCOG Press ; 2004 . 4. Silversides CK , Colman JM , Sermer M , et al. Cardiac
risk in pregnant women with rheumatic mitral stenosis . Am J Cardiol 2003 ; 91 : 1382–5 .
5. European Society of Gynecology (ESG) , Association for European Paediatric Cardiology (AEPC) , German Society for Gender Medicine (DGesGM) , et al.
ESC Guidelines on the management of cardiovascular diseases during pregnancy: Th e Task Force on the Management of Cardiovascular Diseases during Pregnancy of the European Society of Cardiology (ESC) . Eur Heart J 2011 ; 32 : 3147–97 .
6. Nercolini DC , da Rocha Loures Bueno R , Eduardo Guerios E , et al. Percutaneous mitral balloon valvuloplasty in pregnant women with mitral stenosis . Catheter Cardiovasc Interv 2002 ; 57 : 318–22 .
7. Routray SN , Mishra TK , Swain S , et al. Balloon mitral valvuloplasty during pregnancy . Int J Gynaecol Obstet 2004 ; 85 : 18 – 23 .
8. Gupta A , Lokhandwala YY , Satoskar PR , et al. Balloon mitral valvotomy in pregnancy: Maternal and fetal outcomes . J Am Coll Cardiol 1998 ; 187 : 409–15 . 9. Sivadasanpillai H , Srinivasan A , Sivasubramoniam
S , et al. Long term outcome of patients undergoing balloon mitral valvotomy in pregnancy . Am J Cardiol 2005 ; 95 : 1504–6 .
10. Aggarwal N , Suri V , Goyal A , et al. Closed mitral valvotomy in pregnancy and labour . Int J Gynecol Obstet ; 2005 : 118–21 .
11. Hameed A , Karaalp IS , Tummala PP , et al. Th e eff ects of valvular heart disease on maternal and fetal outcome of pregnancy . J Am Coll Cardiol 2001 ; 37 : 893–9 .
12. Aria F , Pineda J . Aortic stenosis and pregnancy . J Reprod Med 1978 ; 20 : 229–32 .
13. Silversides C , Colman J , Sermer M , et al. Early and intermediate-term outcomes of pregnancy with congenital aortic stenosis . Am J Cardiol 2003 ; 91 : 1386–9 .
14. Tzemos N , Silversides CK , Colman JM , et al. Late cardiac outcomes aft er pregnancy in women with congenital aortic stenosis . Am Heart J 2009 ; 157 : 474–80 . 15. Magne J , Lancellotti P , Pierard LA . Exercise testing in
asymptomatic severe aortic stenosis . J Am Coll Cardol Cardiovasc Imaging 2014 ; 7 ( 2 ): 188–99 .
16. Radford D , Walters DL . Balloon aortic valvotomy in pregnancy . Aust N Z J Obstet Gynaecol 2004 ; 44 : 577–9 . 17. Gopal K , Hudson IM , Ludmir J , et al. Homograft aortic
root replacement during pregnancy . Ann Th orac Surg 2002 ; 74 : 243–5 .
18. Parry AJ , Westaby S . Cardiopulmonary bypass during pregnancy . Ann Th orac Surg 1996 ; 61 : 1865–9 . 19. Chambers CE , Clark SL . Cardiac surgery during
pregnancy . Clin Obstet Gynecol 1994 ; 37 : 316–23 . 20. Jahangiri M , Clarke J , Prefumo F , et al. Cardiac surgery
during pregnancy: Pulsatile or non-pulsatile perfusion?
J Th orac Cardiovasc Surg 2003 ; 126 : 894–5 . 21. Ioscovich AM , Goldszmidt E , Fadeev AV , et al.
Peripartum anesthetic management of patients with aortic valve stenosis: A retrospective study and literature review . Int J Obstst Anesth 2009 ; 18 : 379–86 . 22. Suntharalingam G , Dob D , Yentis SM . Obstetric
epidural analgesia in aortic stenosis: A low-dose technique for labour and instrumental delivery . Int J Obstet Anesth 2001 ; 10 : 129–34 .
Heart Disease and Pregnancy, 2nd edn. ed. Philip J. Steer and Michael A. Gatzoulis. Published by Cambridge University Press.
© Cambridge University Press 2016.
Chapter
Practical practice points
1. Right heart lesions usually lead to abnormal loading conditions for the right ventricle, which are particularly important if the right ventricle has to support the systemic circulation.
2. Pregnancy may have a long-term deleterious eff ect on right heart function in such cases.
3. Stenosis is more important than regurgitation.
4. Atrial arrhythmia is an important complication.
5. In women with cyanosis, thromboprophylaxis is particularly important.
6. Miscarriage is more common, especially in women with a Fontan circulation, and fetal growth is oft en impaired .
Introduction
Congenital heart disease (CHD) is the most common birth defect, with an incidence of 0.8% among infants around the world. Th e continual improvement in med- ical and surgical therapy over the past decades has led to >85% of children with congenital heart lesions now surviving into adulthood.[ 1 , 2 ] It can therefore be esti- mated that more than 250 000 adults with congenital heart lesions are currently living in the UK.[ 3 ] Half of these are women, mostly of reproductive age. About 40% of people born with congenital heart defects have lesions predominantly aff ecting the right heart.[ 4 ] Right heart lesions increase the risks of pregnancy to both the mother and the fetus, and the women aff ected require specifi c care to minimize maternal and fetal morbidity and mortality .
Th is chapter highlights some key issues that women with right-sided congenital heart lesions face. It fi rst summarizes some general considerations related to their management and then focuses on specifi c lesions
that predominantly aff ect the right heart and discusses how these may aff ect women going through pregnancy.
General considerations
Preconception evaluation and counseling
Th e management of women with congenital right heart lesions should ideally begin before conception.[ 5 – 7 ] A careful assessment of functional capacity is needed to estimate the likelihood that the women will tolerate the hemodynamic burden of pregnancy and its poten- tial complications. Preconception evaluation should include a careful history and physical examination, an echocardiogram, electrocardiography (ECG) and a cardiopulmonary exercise test. Cardiac magnetic reso- nance imaging (CMR) should be a routine part of this evaluation in women with systemic right ventricles (transposition of the great arteries [TGA] aft er an atrial switch operation [Mustard or Senning]), or congenitally
“corrected” transposition of the great arteries [ccTGA]) and functional univentricular hearts with or without a Fontan-type operation because trans thoracic echocar- diography may provide only limited information on ventricular function. On the basis of this evaluation, the potential risks of pregnancy should be discussed with the woman and her family, ideally in a joint clinic involving, at least, a cardiologist specializing in CHD and an obstetrician specializing in high-risk pregnancy.
Th e risk of pregnant women with CHD suff ering adverse cardiovascular events such as symptomatic arrhythmia, stroke, pulmonary edema, overt heart failure, or death increases with the anatomical com- plexity of the congenital heart lesion, the degree of cya- nosis, myocardial dysfunction, poor functional class, and the severity of systemic outfl ow tract obstruction.
Based on retrospective and prospective data from a