Further Observations on the Pathology of the Atrioventricular Canal Malformation

Abstract
THIRTY-TWO human hearts having atrioventricular (AV) canal malformation were recently studied. The attention was drawn to the anatomical and geometric aspects of the diseased hearts. It was noted that the defect included a significant portion of the muscular septum as far as its junction with the diaphragmatic wall and significant deficiency in the posterior base of the heart. Also, there were major anomalies of the right ventricle, mainly hypoplasia of the septal portion of the right ventricular sinus, and hyperdevelopment of the conal portion of the right ventricle. To the best of our knowledge, the anomalies involving the base of the heart and the ventricles were not described before and they may have some implication as to the surgical approach as well as to the developmental anomaly. The purpose of this communication is to give an anatomic description of the AV canal heart and to define the involved structures, morphologically.