Congenital dysplastic left ventricle simulating anomalous origin of the left coronary artery

ABSTRACT

The authors describe a rare case of congenital dysplasia of the left ventricle. Clinical findings were suggestive of anomalous origin of the left coronary artery from the pulmonary artery. The left ventricle showed areas of endocardial fibroelastosis, with an abnormal and unusually fine, sometimes lacy, filigreelike trabeculation of the internal surface of the endocardium. The endocardium resembled a mat of webbing on the endocardial surface. Many of these fine bands traversed the ventricular cavity from wall to wall. The abnormal Q waves seen on the electrocardiogram may have been caused by an abnormal depolarization process that may have been taking place in the left ventricular trabecular net. Experimental embryologic work in the chick embryo demonstrated that the development of trabecular sheaths in the primitive ventricle that are oriented in a dorsoventral direction are an essential step in ventricular formation. The authors speculate that perhaps an arrest or delay in the full fusion of some trabecular sheaths may give rise to the intracavitary trabeculations demonstrated here.