Wide splitting of the first heart sound secondary to tricuspid valve endocarditis. A phonocardiographic-echocardiographic study.

A patient is described with tricuspid valve endocarditis in whom the vegetation interfered with valve closure resulting in marked wide splitting of the first heart sound. M-mode and two-dimensional echocardiographic studies detected the presence of a vegetation. Simultaneous phonocardiographic and echocardiographic studies documented the marked delay in tricuspid valve closure and differentiated wide splitting of the first heart sound from other causes of early and mid-systolic sounds. Following pulmonary embolization, the first heart sound returned to normal. Echocardiographic disappearance of the vegetation of the tricuspid valve was also noted. Regrowth of the vegetation again produced the abnormal phonocardiographic and echocardiographic findings.