Influence of abciximab on evolution of left ventricular function in patients with non-ST-segment elevation acute coronary syndromes undergoing PCI after clopidogrel pretreatment: lessons from the ISAR-REACT 2 trial

Abstract

Background: Abciximab reduced the combined endpoint of death, myocardial infarction (MI) and target vessel revascularization in patients with non-ST-segment elevation acute coronary syndromes (NSTE-ACS) undergoing percutaneous coronary intervention (PCI) with stent implantation after a 600-mg loading dose of clopidogrel. The aim of the present study was to investigate the impact of abciximab on the evolution of left ventricular ejection fraction (LVEF) in these patients.

Methods: The current study included 1,158 patients enrolled in the randomized, double-blind ISAR-REACT 2 (the Intracoronary Stenting and Antithrombotic Regimen: Rapid Early Action for Coronary Treatment) trial who had paired angiograms obtained at baseline and 6-8 months after randomization. Of them, 586 patients received abciximab and 572 patients received placebo. The primary outcome analysis was LVEF at 6-8-month follow-up.

Results: Baseline LVEF was comparable in patients assigned to abciximab or placebo (53.2 ± 12.6 vs. 53.7 ± 12.1%; P = 0.393). At 6-8-month follow-up angiography, there was no difference in LVEF between the abciximab and placebo groups (55.4 ± 11.5 vs. 55.8 ± 11.2%; P = 0.743). Subgroup analysis of patients with elevated baseline troponin (>0.03 μg/L) also revealed comparable LVEF at follow-up in both treatment groups (P = 0.527). The multivariate analysis identified age, arterial hypertension, prior MI, prior coronary artery bypass graft surgery, baseline LVEF, MI at 30 days and repeat PCI as independent correlates of follow-up LVEF.

Conclusion: Although abciximab reduced the 30-day and 1-year incidence of major adverse cardiac events in patients with NSTE-ACS undergoing primary PCI after pre-treatment with a 600-mg loading dose of clopidogrel, the agent did not improve or impact on the evolution of LVEF over 6-8 months of follow-up.