Fetal cardiomyopathy--in utero evaluation and clinical significance.

OBJECTIVE: To describe the prenatal diagnosis and outcome of fetal cardiomyopathy (CM).

METHODS: The charts, photographs and videotapes of all fetuses with CM, who were assessed during pregnancy at two referral centers, were reviewed.

RESULTS: The diagnosis of CM was established in 12 fetuses. All had structurally normal hearts, and all cases were diagnosed after 23 weeks of gestation, following normal early fetal echocardiogram. Three clusters of fetal CM appeared: Familial--two sib fetuses of a mother, who is a second generation of CM. Both had dilated CM and pathological findings were consistent with the diagnosis of endocardial fibroelastosis. Secondary--CM that was induced by another factor. Idiopathic--six cases of CM without an underlying specific etiology. Three women elected to terminate their pregnancy. Among the nine who delivered, four had a favorable outcome with normal cardiac function at the age of 1 month, in which three belonged to the secondary category, and five cases were complicated by fetal/infant death.

CONCLUSIONS: CM may develop during fetal life and might be diagnosed by prenatal echocardiography. Normal cardiac findings in a midtrimester fetus do not exclude subsequent development of CM. Detailed prenatal sonographic examination may aid in determining the neonatal outcome.