Abnormalities of the coronary circulation in pulmonary atresia and intact ventricular septum

To identify developmental aspects and establish morphologic criteria useful for clinical recognition of sinusoids and coronary artery abnormalities in pulmonary atresia and intact ventricular septum, we studied 17 autopsy hearts with this lesion. Hearts from age- and weight-matched infants served as controls. There were two stillborn fetuses, 12 full-term neonates, and 3 infants. None of the eight hearts with normal or large-sized right ventricular chambers had sinusoids or coronary artery abnormalities. Five of nine hearts with small right ventricular chambers had sinusoids; all five lacked trabecular and outlet portions of the ventricle. Four of these five contained major coronary artery abnormalities: atrophy of one or both coronaries proximal to a communication between a sinusoid and the coronary artery. We conclude (1) there is a strong association between the presence of sinusoids and coronary anomalies, supporting the developmental concept of abnormal persistence of embryonic right ventricular sinusoid--coronary artery communications in pulmonary atresia and intact ventricular septum; (2) the absence of trabecular and outlet portions of the small right ventricle indicates a strong possibility of coronary artery abnormalities; and (3) this initial report of a fully-developed lesion in a mid-gestation fetus documents that the coronary artery problem may arise early in fetal life.