Congenital pulmonary valvular insufficiency complicating tetralogy of fallot: Intracardiac sound and pressure correlates

Abstract

A case of tetralogy of Fallot with organic pulmonic insufficiency is presented with confirmation by cardiac catheterization with angiocardiography and simultaneous intracardiac phonocardiography and pressure measurements. Simultaneous intracardiac sound and pressure correlates proved valuable in elucidating the mechanism for the production of the unusual murmur of organic pulmonic insufficiency. The murmur occurs simultaneously with the low diastolic pressure gradient between the pulmonary artery and the right ventricle during low velocity regurgitation, and is delayed in onset following aortic closure. The silent interval in this study represents the period during isometric relaxation of the hemodynamically functioning “single” ventricle and during early diastole when the respective systolic and diastolic gradients are insufficient to generate audible sound. This case occupies a unique position in the spectrum of pulmonic insufficiency, with hypertensive pulmonic insufficiency and the Graham Steell murmur at one end, and nonhypertensive, isolated congenital pulmonic valvular insufficiency at the other end.