Birthing the Genetics of Peripartum Cardiomyopathy

Abstract

Peripartum cardiomyopathy (PPCM) is an uncommon but increasingly recognized and potentially devastating idiopathic cardiomyopathy that affects women during pregnancy or shortly after delivery.1–3 The medical literature provides reference to PPCM as early as 1849.4 Its recognition as a distinct clinical entity first occurred in 1937,5 and the term PPCM was introduced in 1971 when Demakis proposed the specific diagnostic criterion of onset between the last month of pregnancy and 5 months postpartum.6 Subsequently, the criterion of systolic dysfunction (ie, left ventricular ejection fraction <45% and left ventricular enlargement) was added.7 PPCM was to be applied only when no specific cause or preceding history of heart failure was evident. More recently, Elkayam and colleagues recognized 23 cases of idiopathic dilated cardiomyopathy (IDCM) with onset earlier in pregnancy (as early as week 17), designated them early pregnancy-associated cardiomyopathy (PACM), and found them to be clinically indistinguishable from late PACM (ie, classical PPCM),2 suggesting that the 2 groups may be considered under the inclusive term of PACM. Articles see pp 2169 and 2176 The incidence of PPCM shows large temporal and geographic variations, with more recent articles suggesting an incidence of 1 in ≈2000 to 4000 deliveries (ie, affecting 1000 to 2000 women annually in the United States).1,8 Even higher rates have been reported from South Africa (1:1000), Haiti (1:300), and Nigeria (1:100).1,3 Some of these differences may be accounted for by diagnostic criteria (eg, clinical only versus echocardiographic) and others by pathogenic factors (eg, dietary salt, hypertension, genetic background).3 The clinical presentation of PPCM is indistinguishable from IDCM (ie, new appearance of clinical signs and symptoms of heart failure due to systolic dysfunction, such as fatigue, dyspnea, pulmonary and peripheral edema, and thromboembolic risk).1,3 Treatment goals also are generally similar to that …