Congenital absence of the pulmonary valve

Abstract

Clinical manifestations, diagnostic studies, and pathologic findings in 5 autopsyproved cases of congenital absence of the pulmonary valves are summarized. Anatomically, only scattered flat nubbins or ridges, apparently representing rudimentary valve tissue, were found in a well-delineated annular zone in place of the normal semilunar pulmonary cusps. In each case, a large ventricular septal defect and aneurysmal dilatation of the main pulmonary arteries were present. Three, and possibly 4, of the infants had tetralogy of Fallot as well, and thus belonged to the increasingly recognized group of patients with this combination of lesions. The fifth infant had a severe form of common atrioventricular canal, double-outlet right ventricle, and an abnormal aortic sinus of Valsalva-right ventricular communication in addition to absence of the valves. Each of the patients died in early infancy (1 month to 6 months), and the cause of death was attributed to two factors: obstruction of the respiratory tract due to the aneurysmal pulmonary arteries, and heart failure. Hence, the prognosis for infants with these findings appears to be poor. Characteristic auscultatory findings consist of a loud, rough systolic murmur and an early diastolic (to-and-fro) murmur which, together with absence of the pulmonary closure sound and normal systemic pulse pressure, strongly suggest an absence of the pulmonary valves. Markedly dilated pulmonary arteries are seen radiologically.