Isolated congenital pulmonary regurgitation with right ventricular outflow tract aneurysm--a rare variant of Uhl's anomaly.

Isolated absent pulmonary valve syndrome is a very rare entity. We report the case of a four-year-old boy who had congenital absent pulmonary valve with a thin and aneurysmal right ventricular infundibulum. The histological picture was suggestive of Uhl's anomaly. This association of partial right ventricular Uhl's anomaly with absent pulmonary valve syndrome has not been described before. We discuss the embryological and clinical significance of this association.