Clavicular Auscultation. Preferential clavicular transmission and amplification of aortic valve murmurs.

Clavicular transmission of aortic valve murmurs was investigated in 15 consecutive patients. In all patients, transmission to the clavicle of aortic systolic murmurs was detected both by auscultation and by phonocardiographic studies. Of seven patients with aortic diastolic murmurs, auscultation revealed clavicular transmission in six, but only four were recordable. There was increased murmur amplitude over the clavicle in 13 out of 15 cases. In contrast, murmurs were attenuated over the subclavian artery in eight out of nine and over the carotid artery in nine out of 11 patients. We conclude that clavicular auscultation regularly discloses aortic valve murmurs. The aortic systolic murmurs are consistently propagated to the clavicle, where they are usually conspicuously amplified. Aortic systolic murmurs are less frequently transmitted to the carotid and subclavian arteries, where they are usually considerably attenuated. Clavicular auscultation appears to be more rewarding than the traditional search for transmission of aortic murmurs to the carotid artery.

Auscultatory perception of the fourth heart sound: effects of interval form fourth to first sound (S4-S1) and aging.

A clinically heterogeneous group of 48 subjects (aged 19 to 76 years) were searched for a fourth heart sound (S4) by three independent "blind" auscultators. Phonocardiograms recorded immediately after auscultation were measured by another "blind" observer. An S4 was identified in 32 subjects (67 per cent) in phonocardiograms with nominal filter peaks of both 70 and 35 hertz. Results in these subjects revealed two groups by auscultatory performance: those with an "easily heard" and those with an "easily missed" S4. Subjects with an "easily missed" S4 were significantly younger than those with an "easily heard" S4 (31.2 +/- 2.8 years versus 50.0 +/- 4.0 years, P less than 0.001). P-R and P-S4 intervals and relative amplitude of S4 (ratio of fourth to first heart sound [S1] amplitude) were not significantly different in the two groups. Splitting of the first heart sound (S1) was observed more frequently in the phonocardiogram of patients with an "easily missed" S4, but this trend did not reach statistical significance. The interval between S4 and the low frequency component of S1 was significantly short in those with an "easily heard" S4 (49.4 +/- 4.1 msec versus 70.0 +/- 5.0 msec, P less than 0.005). The mean S4-S1 (low frequency component) interval for the group with an "easily heard" S4 approximated 1 cycle length for S4 vibrations, a finding consistent with temporal acoustic summation. An alternate hypothesis is modification of S1.

Effects of age on responses to isometric exercise. Isometric handgrip in noninvasive screening for cardiovascular disease.

Isometric handgrip (IHG) imposes an acutely increased afterload on the left ventricle. Utilizing systolic time intervals, we studied various responses to IHG, measured as changes from resting values with near-maximum IHG, in old normal (ON) subjects, young normal (YN) subjects, and old patients with hypertensive heart disease (HHD) and patients with coronary artery disease (CAD). There were no differences in responses to IHG between ON and patients with HHD or patients with CAD. However, there were clear differences between the responses of ON and YN subjects. Increase in heart rate (HR) was much more prominent in YN (ON vs. YN = +11.6 +/- 2.6 vs. +15.6 +/- 5.7 beats per minute p less than 0.001). Pre-ejection period (PEP) end isovolumic contraction time (IVCT) increased in ON but decreased in YN (PEP + 6.2 +/- 1.7 vs. -11.0 +/- 3.7 msec., p less than 0.001; IVCT +8.1 +/- 2.2 vs. -13.8 +/- 3.4 msec., p less than 0.001. Shortening of LVET was much more marked in YN (-6.5 +/- 4.1 VS. -63.3 +/- 9.9 msec. p less than 0.001), but this was entirely due to the HR differences since there was no difference in ejection time index (+ 5.1 +/- 3.4 vs. -0.4 +/- 7.3 msec. p greater than 0.5). IHG produced no significant differences between ON and YN in the timing of the "mitral" component of the first heart sound (q-Im), in the ratio PEP/LVET, or in pulse transmission time (PTT). By contrast, resting control PTT was markedly short in ON, especially those with CAD. Resting PTT in ON was 27.1 +/- 2.6 msec.; in YN 43.7 +/- 1.4 msec.; in CAD patients 20.7 +/- 1.3 msec. We conclude that even near-maximal IHG does not seem to be an adequate noninvasive screening test for cardiovascular disease in that age alone seems to have the most significant influence on the responses.