Since this is the “American Heart Month,” we felt it was time to address the fact that cardiovascular diseases are the most frequent cause of maternal death in pregnancy. Because ever older women are now conceiving, often with donated eggs from younger women, we have started to see cardiovascular diseases in pregnant women - especially after fertility treatments – which, only a few decades ago, were practically unknown.
It is important to initiate his brief review by being very clear that, just because a woman suffers from a cardiovascular disease does not mean she cannot or should not conceive. A large majority of women with such disorders, indeed, can safely go through pregnancy, though there are a few conditions that are, usually, considered contraindications to pregnancy. Those are, primary pulmonary hypertension and the so-called Eisenmenger syndrome, characterized by a cardiac septal defect and resulting secondary pulmonary hypertension. Some of the earliest publications of The CHR’s Medical Director and Chief Scientist, Norbert Gleicher, MD, were, indeed, on Eisenmenger syndrome in pregnancy.1,2 In both of these conditions maternal mortality in pregnancy used to be so high that both conditions were considered absolute contraindications to pregnancy and, if pregnancy occurred, medical termination was considered indicated. But cardiac medical treatment greatly improved since the late 1990s, and now a more measured approach appears indicated. A very recent Chinese study, for example, offered new food for thought regarding pulmonary hypertension in general because these investigators were able to accumulate data on 154 affected women, a very large number for a very rare condition in pregnancy: In this study population, 3.9% had idiopathic pulmonary arterial hypertension iPAH) 26.6% had pulmonary arterial hypertension (PAH) associated with congenital heart disease (CHD-PAH), 29.2% had PAH related to other diseases (oPAH), and 40.3% had PH related to left heart disease (LHD-PH).
Only 3.2% of these women- less than 10% of what the mortality, likely, would have been in the 1990s – died within one week from delivery (this time frame is important because most deaths in association with this condition happen shortly after delivery). This number may, however, be misleading because among iPAH patients 3/6(50%) died, - a very similar number to 1990s rates. At 35.1%, ICU admissions were, overall, surprisingly low since patients with PH in the 1990s would in almost all cases have been delivered in an ICU setting. Moreover, congestive heart failure (CHF) was also unexpectedly low at 14.9%. Unsurprisingly, 70.1% of women delivered by Cesarean section, even though in the old days operative delivery was actually considered a risk factor.
As one would expect offspring were also affected: 42.0% of pregnancies had premature deliveries; 28.6% had low birth weight, 13.0% had very low birthweight, and 3.2% had extremely low birth weight infants; 61.0% had small for gestational age infants, and 1.9% of offspring succumbed.
Though numbers of iPAH patients was relatively small, that they experienced a so much higher mortality than other forms of the disease, led the authors to the recommendation that, in iPAH patients, pregnancy should, still, be considered as contraindicated. But, without explicitly saying so, this also means that in other conditions accompanied by PH, including Eisenmenger syndrome, pregnancy may be considered. Another very recent study, this time from India, however, in a much smaller group of 12 pregnancies with Eisenmenger syndrome reported a 37% maternal mortality rate in the postpartum period,4 - not very different from rates reported in the 1990s. This much higher mortality in this group than in the Chinese study may be due to the fact that almost 80% of patients in the Indian study were diagnosed with Eisenmenger only while already pregnant.
This potential explanation also points out one of the most important principles in management of maternal diseases in pregnancy: Correct diagnosis before pregnancy is essential if best outcomes are to be achieved. First diagnosis in pregnancy almost universally will produce poorer results, with two reasons contributing: First early diagnosis allows for proper preparation of the patient, so conception can be planned when she, considering her medical problem, is in best possible physical and mental shape. Cardiac problems are a very good example: If, for example, a cardiac patient constantly veers on the verge of CHF, this is not the time to conceive. Indeed, acute CHF is also considered a contraindication for pregnancy. But once a woman’s hemodynamics have been appropriately controlled, she will be in a much safer condition to conceive. A second reason is that medical treatments will always be better if need for treatment is expected than when it comes as a surprise. In other words, it is, of course, always better to be prepared than to be surprised.
If these ground rules are followed, most women with cardiovascular problems will sail safely through pregnancy, - even if older. They, of course, should be managed by a team made up of gynecologists, infertility specialists, perinatologists, neonatologists, anesthesiologists and, of course, cardiologists that, ideally is assembled before the patient conceived. The responsibility for the assembly, therefore, usually falls on the patient’s general gynecologist or fertility specialist. Suffice to say, cardiac patients should deliver in a tertiary medical center with ICU and advanced neonatal care, at which all members of the assembled team have privileges.
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