The left ventricle in congenital isolated pulmonary valve stenosis. A morphological study.

The wall thickness of the left ventricle was measured in the hearts of 16 children and 2 adults who died of congenital pulmonary valve stenosis. A right-to-left shunt through a patent foramen ovale had existed in 12 cases and was excluded in the other 6. The thickness of the left ventricular wall and the interventricular septum was increased in the majority of hearts, especially in the older patients. There was a good correlation between wall thickness and histological appearance of the left ventricular myocardium; in 2 cases there was also evidence of left ventricular myocardial fibrosis. The coronary arteries appeared normal in all cases. A direct interaction between the ventricles was thought to be a possible mechanism.