The Click-Murmur Syndrome

Abstract

AUSCULTATORY sounds of a late systolic murmur, with or without a preceding nonejection click, have been generally recognized since the late 1950s to result from abnormal movement of the mitral valve apparatus during systole. Although the mitral valvular origin of these sounds was suspected before, it was only after left ventricular angiography showed the late systolic murmur to result from mitral insufficiency, which was secondary to the abnormal billowing of the mitral leaflets into the left atrium, that the true nature of these auscultatory findings was recognized. The patient with a nonejection click, with and without a systolic murmur, has been described in the literature under a wide variety of names (Table 1). With the demonstration by echocardiography of the abnormal posterior systolic movement of both aortic and mural leaflets of the mitral valve, it has been possible to identify noninvasively the patients with an abnormally prolapsing mitral valve, even