Clinical significance of early or mid-systolic apical murmurs: analysis by phonocardiography, two-dimensional echocardiography and pulsed Doppler echocardiography.

The records of 2,000 consecutive patients who had been examined by auscultation, phonocardiography (PCG), two-dimensional echocardiography and pulsed Doppler echocardiography (PDE) were reviewed to assess the clinical significance of apical systolic murmurs which cease well before the aortic closure sound. Fifty-five patients were verified to have early or mid-systolic apical murmurs. Mitral regurgitation (MR) was detected in 32 patients by PDE (29/32) and/or PCG with methoxamine test (27/32). The degree of MR was judged to be mild by PDE in all cases. Apical systolic murmurs due to MR began mainly with the first heart sound (27/32), were confined to the apex (27/32), and high-pitched (25/32). Their intensity was grade III/VI or less in all cases. Mitral valve prolapse (12 patients) was the most common cause of MR. Other causes were rheumatic mitral involvement in seven patients, dilated or ischemic cardiomyopathy in five, mitral annular calcification in three, and hypertrophic cardiomyopathy in two. The causes of the MR in the remaining three patients could not be identified. Thus, early or mid-systolic apical murmurs are mainly attributable to mild MR which can be diagnosed by careful auscultation, PDE and/or PCG with the methoxamine test.