Effect of Diltiazem on Coronary Hemodynamics and Its Clinical Significance

Cardiovascular Effects of Diltiazem in the Dog

“…Diltiazem proved to be a potent systemic vasodilator. This is in accordance with previous studies [3,22]. Except during the low-dose infusion, the reductions in SVR were accompanied by a decrease in AoP.…”

Diltiazem

“…In only one report was diltiazem found to reduce blood flow; this occurred in the renal bed of the anesthetized rat (8). Prior to ours, only two studies investigated the effect of diltiazem in a conscious animal preparation (27,148). In both cases, diltiazem increased coronary blood flow substantially, but the magnitude of the effect was similar to that obtained in anesthetized preparations by other investigators.…”

“…In the intact conscious dog, diltiazem (2 mg/kg i.v.) has been shown to increase coronary blood flow acutely by as much as 90%, with proportionate decreases in coronary vascular resistance (148). Franklin et al (27) obtained a similar effect in a conscious canine model at a dose of 0.02 mg/kg.…”

Diltiazem

“…TM On the other hand, in humans with variant angina pectoris, diltiazem exerts a powerful and longlasting vasodilating action on the coronary vasculature, including the diseased narrowed portions of the vessels. 56 In dogs in whom an acute total occlusion of the left anterior descending coronary artery has been induced, an intravenous injection of a large bolus of diltiazem 75 or a four-hour diltiazem infusion 76 increases regional myocardial blood flow in the control area and in the moderately and mildly ischacmic areas but does not improve myocardial blood flow of the severely ischaemic areas. 75'~6 Flow to, and therefore function of, ischaemic myocardial segments which are not dyskinetic is improved.…”