Pregnancy outcomes in women with dilated cardiomyopathy: Peripartum cardiovascular events predict post delivery prognosis

Background: The number of pregnant women with dilated cardiomyopathy (DCM) is relatively small, and therefore their prognosis after pregnancy is unknown. This study aims to elucidate pregnancy outcomes among women with DCM, as well as the long-term prognosis after pregnancy. Methods: Thirty-five pregnancies and deliveries in 30 women, diagnosed with DCM before pregnancy, were retrospectively analyzed. Results: All women had a left ventricular ejection fraction (LVEF) over 30% and belonged to the New York Heart Association (NYHA) class I or II before pregnancy. The mean gestational age at delivery was 36 weeks with 15 (43%) preterm deliveries. Eight pregnancies (23%) were complicated by peripartum cardiac events including 1 ventricular arrhythmia, 6 heart failures, and 1 significant deterioration in LVEF requiring termination of pregnancy. NYHA class II, pre-pregnancy use of angiotensin-converting enzyme inhibitor/angiotensin II receptor blocker/diuretics, elevated brain natriuretic peptide (BNP), and advanced diastolic dysfunction assessed by Doppler echocardiography were defined as risk factors for cardiac events. Although the more severe cases took beta-blockers during pregnancy, the rates of cardiac events and decreasing LVEF did not differ significantly between those taking beta-blockers and those who were not. Values of LVEF decreased by almost 10% after the average 4-year post-delivery follow-up period. The long-term event-free survival was considerably worse among women with peripartum cardiac events than in those without (p < 0.0001). Conclusions: DCM women with pre-pregnancy LVEF over 30% tolerated pregnancy, but the rate of preterm delivery was high. Peripartum cardiovascular events occurred more often in women with NYHA class II, as well as those who received medications before and during pregnancy and showed more elevated BNP and advanced diastolic dysfunction before pregnancy. Beta-blockers likely allowed similar outcomes for DCM patients with lower initial LVEFs. Close monitoring later in life is required, particularly among the women with peripartum cardiac events.