Heart sounds and murmurs in arterial hypertension

Forty-three patients with hypertension were studied by an improved method of phonocardiography. On graphic analysis, the first heart sound at the apex and aortic area was generally normal in amplitude and duration. The second heart sound at the aortic area was increased in amplitude and duration in almost all instances. It was usually composed of regular high frequency vibrations. Third and fourth heart sounds of low frequency and low amplitude were found quite often. A third heart sound was noted only in the presence of left ventricular hypertrophy. An apical presystolic murmur of low frequency and low amplitude was recorded in five patients. Aortic and apical systolic murmurs were noted often; these murmurs were usually low in intensity and of low to medium frequency. A basal diastolic murmur was recorded in nine of ten patients in whom the murmur was heard clinically. We believe that it suggests insufficiency of the aortic valve. The diastolic vibrations were low in amplitude and more readily detected when a frequency band of 150 to 200 c.p.s. was selected. They immediately followed the second heart sound and were best visualized at the third left parasternal area. The presence of the murmur did not seem to be related to the level of the systolic, diastolic or pulse pressures at the time of the technical procedure. It was found only in patients with left ventricular hypertrophy. The Q-1 interval was prolonged, particularly in the group with aortic insufficiency.