Comparison between apexcardiographic and angiographic indexes of left ventricular performance in patients with aortic incompetence.

Left ventricular (LV) apexcardiogram (ACG) and its first derivative (dA/dt) was obtained in 104 normal subjects and 34 patients with chronic aortic incompetence (AI). In the patients with AI the ACG was recorded simultaneously with LV pressure (tipmanometer). The systolic upstroke time (SUT), the time to peak dA/dt (t-dA/dt) and the a wave percentage amplitude (a/H) of the ACG was measured. In normal subjects SUT averaged 99 +/- 17 (SD) msec. In 17 patients with AI and normal ejection fraction (EF) (group 1) SUT was within normal limits; in 17 patients with AI and decreased EF (group 2) it was prolonged (142 +/- 19 msec) (P less than 0.001). The SUT was closely correlated with EF (r = 0.85) and less with contractile indexes derived from pressure curves. The indexes t-dA/dt and a/H were not significantly different in groups 1 and 2; they were weakly correlated only with the time to peak rate of LV pressure rise (r = +0.56) and the LV end-diastolic pressure (r = +0.59), respectively. These results demonstrate the superiority of SUT over the other apexcardiographic parameters. The measure provides another means of noninvasive assessment of the LV performance in patients with AI.