Published online by Cambridge University Press: 19 August 2008
To identify the echocardiographic features and natural history of dilated cardiomyopathy in fetal life, we reviewed records of all fetal echocardiograms over the 10 year period 1980–1989 to identify cases of dilated cardiomyopathy without left ventricular outflow obstruction and conducted a retrospective review of the fetal echocardiograms and clinical course of those fetuses with dilated cardiomyopathy. In addition, all fetal losses, perinatal deaths and live-born infants presenting with dilated cardiomyopathy in the first seven days of life were identified from the British Columbia Pediatric Cardiovascular Pathology Registry and from inpatient records. The pathological findings and outcome for this group were also reviewed. Marked left ventricular dilatation and dysfunction without left ventricular outflow obstruction was diagnosed in five of 1,158 fetuses undergoing feta lechocardiography. These five fetuses were correctly distinguished from two others with critical aortic stenosis and severe left ventricular dysfunction. Two of the five fetuses had additional right ventricular dysfunction and dilatation and developed hydrops, while the remaining three with isolated severe left ventricular dysfunction did not and showed normal somatic growth. All fetuses were live-born with spontaneous labour occurring in four of five cases at a mean gestational age of 36.5 weeks. Four of the five infants died, with three deaths occurring in the first week of life. During the same 10 year period, two of 2450 autopsied stillbirths (both hydropic) were diagnosed with dilated cardiomyopathy. An additional 15 neonates (including the five identified by fetal echocardiography) were diagnosed in the first week of life with dilated cardiomyopathy, congenital myocarditis or endocardial fibroelastosis. Four were hydropic (all with associated right ventricular dysfunction). Only three of the 15 survive. Fetal echocardiography can accurately distinguish dilated cardiomyopathy from left ventricular outflow obstruction. In the absence of right-sided disease or premature closure of the oval fossa, severe left ventricular dysfunction is well tolerated in utero. The prognosis for fetal dilated cardiomyopathy is very poor.