A PHONOCARDIOGRAPHIC STUDY OF APICAL DIASTOLIC MURMURS SIMULATING THOSE OF MITRAL STENOSIS

Abstract

A clinical and graphic study of apical diastolic murmurs simulating those of mitral stenosis is reported. The study includes cages of mitral insufficiency without appreciable stenosis, aortic insufficiency (Austin Flint murmur), coronary and hypertensive heart disease, adhesive pericarditis, and disturbances of the rate and rhythm. In a 1st group of cases, the phonocardiogram revealed that the murmur was not caused by mitral stenosis. This group included cases with arrhythmia, mitral insufficiency, adhesive pericarditis, and some cases of coronary and hypertensive heart disease. In most of the cases the so-called murmur resulted from an auscultatory illusion and was caused either by a gallop or by a crescendo-type 1st sound. In a 2d group of cases, the phonocardiogram revealed diastolic-presystolic vibrations simulating those of mitral stenosis; the functional nature of the murmur was revealed by either the subsequent clinical course or negative postmortem findings. This group included patients with aortic insufficiency (Austin Flint murmur), coronary heart disease, and auricular flutter. It is concluded that, while the phonocardiogram permits recognition of the nature of the murmur in a large number of cases, it fails to do so in a minority. The cause of the functional diastolic murmur at the apex is discussed.