Familial Congenital Complete Heart Block

Abstract

In general, the occurrence of congenital heart disease may be considered to be due to genetic factors, environmental factors, or a combination of the two. When an identical defect is found in more than one member of the same family, a genetic etiology is suggested. The medical literature reveals numerous reports of a wide variety of congenital heart lesions occurring in families. Taussig,¹for example, reported on a family in which patent ductus arteriosus appeared in 3 successive generations. This experience provides strong exidence that at least certain types of congenital heart lesions may have a genetic basis. Complete congenital heart block is an uncommon lesion, having been reported only slightly over 100 times in the world literature. The etiology of this condition remains unsettled. Autopsy reports^2-9which include detailed histologic study of the conduction system have revealed that most often the atrioventricular node was separated from the