Contractility of the hypertrophied human left ventricle in chronic pressure and volume overload.

Abstract Nine patients with normal left ventricles (C), 10 patients with pressure load (PL) due to predominant aortic stenosis, and 9 patients with predominant volume load (VL) due to aortic incompetence were studied by left ventricular high-fidelity pressure measurements and cineangiography. Peak measured velocity of the contractile elements (V pm ) used as index of contractility and left ventricular muscle mass (LMMI) were determined. The patients with PL and VL were matched with respect to LMMI. In PL LMMI was 241 ± 41 and in VL 254 ± 42 gm. per square meter. Both were sizably increased (P pm was 1.41 ± 0.20 ML per second in C. In PL and VL V pm was reduced to 1.05 ± 0.26 (P pm in PL was not different from V pm in VL. Heart rate showed no major difference in the three groups. It is concluded that in two groups of patients with predominant PL and VL matched with respect to LMMI left ventricular contractility was depressed to a similar extent regardless of the stimulus to hypertrophy.