PLATELET GLYCOPROTEIN IIB IIIA RECEPTOR BLOCKADE AND LOW-DOSE HEPARINDURING PERCUTANEOUS CORONARY REVASCULARIZATION/

Background Blockade of the platelet glycoprotein IIb/IIIa receptor wit h abciximab (a monoclonal-antibody Fab fragment directed against the r eceptor) has been shown to diminish ischemic complications among patie nts undergoing high-risk coronary angioplasty or atherectomy but incre ases bleeding complications. The widespread applicability of this trea tment is unknown, particularly in view of the observed risk of hemorrh age. Methods In a prospective, double-blind trial, we randomly assigne d patients undergoing urgent or elective percutaneous coronary revascu larization at 69 centers to receive abciximab with standard-dose, weig ht-adjusted heparin (initial bolus of 100 U per kilogram of body weigh t); abciximab with low-dose, weight-adjusted heparin (initial bolus of 70 U per kilogram); or placebo with standard-dose, weight-adjusted he parin. The primary efficacy end point was death from any cause, myocar dial infarction, or urgent revascularization within 30 days of randomi zation. Results The trial was terminated at the first interim analysis , with 2792 of the planned 4800 patients enrolled. At 30 days, the com posite event rate was 11.7 percent in the group assigned to placebo wi th standard-dose heparin; 5.2 percent in the group assigned to abcixim ab with low-dose heparin (hazard ratio, 0.43; 95 percent confidence in terval, 0.30 to 0.60; P<0.001); and 5.4 percent in the group as signed to abciximab with standard-dose heparin (hazard ratio, 0.45; 95 perce nt confidence interval, 0.32 to 0.63; P<0.001). There were no signific ant differences among the groups in the risk of major bleeding, althou gh minor bleeding was more frequent among patients receiving abciximab with standard-dose heparin. Conclusions Inhibition of the platelet gl ycoprotein IIb/IIIa receptor with abciximab, together with low-dose, w eight-adjusted heparin, markedly reduces the risk of acute ischemic co mplications in patients undergoing percutaneous coronary revasculariza tion. (C) 1997, Massachusetts Medical Society.