The effect of oral diltiazem on left ventricular performance in postinfarction patients

Abstract

The purpose of the present study was to evaluate the effect of diltiazem on the left ventricular function in postinfarction patients. Twelve patients without cardiac decompensation at rest began diltiazem therapy beginning 3 months after an acute myocardial Q-wave infarction. Oral diltiazem was administered on the first day in a single dose (120 mg) and the following 2 weeks in a 60 mg three times a day (tid) regimen. The therapeutic effect was studied by isotope angiocardiography at rest using equilibrium measurements with technetium-99m. Acute as well as continuous treatment improved left ventricular function in terms of increased synergy of the contraction (decreased phase deviation from a median of 20.0 degrees to median of 12.4 degrees and 13.0 degrees, respectively, p less than 0.01) and increased ejection fraction from a median of 46% to a median of 50% and 51%, respectively, p less than 0.05. It is suggested that the improvement of left ventricular function may be due in part to decreased pressure rate product. This improved left ventricular function during diltiazem treatment may explain the improved prognosis induced by diltiazem in postinfarction patients.