Regional coronary hemodynamic effects of diltiazem in man.
We evaluated the changes in regional coronary hemodynamics induced by diltiazem, 0.25 mg/kg intravenously, in nine patients with 75% to 90% diameter stenosis of the left anterior descending coronary artery (LAD) (group 1) and in 10 patients with 100% occlusion of the LAD and collaterals to the distal LAD (group 2). Although diltiazem induced similar changes in systemic hemodynamics in the two groups, a decrease in anterior coronary vascular resistance (ACVR) and an increase in great cardiac vein flow (GCVF) were observed after administration of diltiazem in all patients in group 1 but in only 6 of 10 patients in group 2 (subgroup 2B). ACVR increased and GCVF decreased after administration of diltiazem in 4 of 10 patients in group 2 (subgroup 2A). Clinico-angiographic characteristics, origin of collaterals, and diltiazem-induced changes in systemic hemodynamics were similar in subgroups 2A and 2B. Thus diltiazem increases coronary flow distal to a stenotic coronary artery but can decrease regional coronary flow and increase regional coronary resistance in a minority of patients with an occluded coronary artery supplied by collaterals, probably through a steal mechanism.
I Cattedra di Medicina Interna, Istituto di Medicina Interna, University of Naples, Italy.
C
C
Vigorito
A
A
Giordano
L
L
De Caprio
V
V
Canonico
P
P
Ferraro
N
N
Farese
P
P
Silvestri
M
M
Catanzaro
F
F
Rengo
D003326:Coronary Circulation / Q000187:drug effects*; D003327:Coronary Disease / Q000145:classification / Q000503:physiopathology*; D004110:Diltiazem / Q000008:administration & dosage / Q000494:pharmacology*; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D008875:Middle Aged
D004110:Diltiazem