Ebstein's anomaly and extracardiac defects.

Ebstein's anomaly of the tricuspid valve occurs as an isolated defect with other forms of congenital heart disease such as transposition of the great arteries or tetralogy of Fallot or, rarely, in association with extracardiac malformations. Because so little is known about this latter group, we studied four cases clinically, at autopsy, and by means of a retrospective chart review. Major extracardiac changes most often involved the craniofacial region, central nervous system, and limbs. Karyotypes were normal, and no distinctive syndromes or anatomic patterns were identified. Since the timing of Ebstein's anomaly is quite precise, ascertainment of such cases on the basis of cardiac morphology may enhance the understanding of etiology and pathogenesis. Both causes and mechanisms may well be diverse, for the clinical histories and anatomic findings in present and previously reported cases vary considerably. Isolated Ebstein's anomaly may develop from topographically and temporally localized damage. Ebstein's anomaly with extracardiac defects may involve damage during a longer, and perhaps earlier, period.