Apical diastolic and presystolic murmurs of proved functional nature

Abstract

We have collected a series of thirty-two clinical cases in which a diastolic or presystolic murmur simulating that of mitral stenosis was recorded in the phonocardiogram. The functional nature of the murmur was proved in nine by autopsy, in ten by right heart catheterization (pulmonic stenosis or septal defect), and in thirteen by left heart catheterization, which revealed the absence of a mitral gradient. A clinical error was made in most cases, except those in which an entirely different clinical picture was present (congenital heart disease, recent myocardial infarct). The phonocardiogram was correctly interpreted in most cases. However, in five cases the tracing was interpreted as being consistent with mitral stenosis. In two of them a “dynamically insignificant” mitral stenosis was suspected, although not proved. In the other three, no stenosis whatsoever was finally admitted. A case in which the murmur was probably due to acute rheumatic carditis is discussed in detail and repeated tracings are presented. The various causes which can lead to a clinical error are listed and it is shown that, in many of these cases, a phonocardiogram helps to rule out mitral stenosis. It is further shown that in a few exceptions even the phonocardiogram can be misinterpreted. Left heart catheterization often reveals the absence of a mitral block thus reducing the doubtful cases (dynamically insignificant lesion) to a minority.