N tusi and associates (2015) analyzed the clinical features of 30 women with peripartum cardiomyopathy compared with 53 women with hypertensive heart failure. With cardiomyopathy, the symptoms began postpartum in all women, whereas symptoms began antepartum in 85 percent of women with hypertensive heart failure. Peripartum cardiomyopathy was significantly linked with twin gestation, smoking, and echo cardiographic abnormalities. In contrast, hypertensive heart failure patients more often had a family history of hypertension, hypertension and preeclampsia in a prior pregnancy, tachycardia, and left ventricular hypertrophy on echo cardiography.
he incidence of peripartum cardiomyopathy varies considerably and depends on the diligence for the search of a cause. In a review of the Nationwide Inpatient Sample database, the incidence rose from 1 in 1181 live births in 2004 to 1 in 849 in 2011 (Kolte, 2014). Two other large population-based studies cite a frequency of 1 in 2000 to 2800 live births (Gunderson, 2011; Harper, 2012). In an earlier study from Parkland Hospital, we identified idiopathic cardiomyopathy in only approximately 1 in 15,000 deliveries-an incidence similar to that of idiopathic cardiomyopathy in young nonpregnant women (Cunningham, 1986).
Approximately half of women sufering from peripartum cardiomyopathy recover baseline ventricular function within 6 months of delivery. But in those with persistent cardiac failure, the mortality rate approaches 85 percent over 5 years (Moioli, 2010). In a group of 100 women with newly diagnosed peripartum cardiomyopathy, 72 percent had a left ventricular ejection fraction ::50 percent, and 93 percent had event-free survival (McNamara, 2015). However, six women experienced nine major events that included four deaths, four left ventricular assist device implantations, and one heart transplantation. Recovery to a left ventricular ejection fraction ::50 percent occurred in almost 90 percent of women whose baseline ejection fraction was at least 30 percent. This compared with <40 percent in women whose baseline ventricular ejection fraction was < 30 percent. Recovery was also related to the baseline left ventricular end-diastolic diameter. Li and colleagues (2016) also found that a baseline left ventricular ejection fraction <34 percent and a brain natriuretic peptide (BNP) level > 1860 pg/ mL were associated with an approximately threefold greater risk of persistent left ventricular systolic dysfunction.
From the largest studies on the topic, approximately one third of women with a history of peripartum cardiomyopathy will sufer relapse with worsening of symptoms and deterioration of left ventricular function during another pregnancy (Elkayam, 20 14a). The risk of relapse in women with persistent left ventricular dysfunction is substantially higher than in those who have developed normal ventricular function before a subsequent pregnancy (Hiliker-Kleiner, 2017). But, normalization of let ventricular function does not guarantee an uncomplicated pregnancy, because approximately 20 percent of these women are at risk for deterioration in left ventricular function.