Pooled Analysis Comparing the Efficacy of Intracoronary Versus Intravenous Abciximab in Smokers Versus Nonsmokers Undergoing Primary Percutaneous Coronary Revascularization for Acute ST-Elevation Myocardial Infarction

Abstract

Cigarette smokers with ST-segment elevation myocardial infarction (STEMI) may present different response to potent antithrombotic therapy compared to nonsmokers. We assessed the impact of smoking status and intracoronary abciximab in patients with STEMI undergoing primary percutaneous coronary intervention (PCI). We pooled data from 5 randomized trials comparing intracoronary versus intravenous abciximab bolus in patients undergoing primary PCI. The primary end point was the composite of death or reinfarction at a mean follow-up of 292 ± 138 days. Of 3,158 participants, 1,369 (43.3%) were smokers, and they had a lower risk of the primary end point in crude, but not in adjusted analyses (hazard ratio [HR] 0.87, 95% confidence interval [CI] 0.63 to 1.21, p = 0.405). Intracoronary versus intravenous abciximab was associated with a significant reduction in the risk of primary end point among smokers (3.6% vs 8.0%; HR 0.43, 95% CI 0.26 to 0.72, p = 0.001), but not in nonsmokers (10.2% vs 9.9%; HR 0.99, 95% CI 0.72 to 1.36, p = 0.96), with a significant interaction (p = 0.009). Furthermore, intracoronary abciximab decreased the risk of reinfarction in smokers (HR 0.30, 95% CI 0.15 to 0.62, p = 0.001), with no difference in nonsmokers (HR 1.20, 95% CI 0.71 to 2.01, p = 0.50). Stent thrombosis was lowered by intracoronary abciximab in smokers (HR 0.28, 95% CI 0.06 to 0.66, p = 0.009), but was ineffective in nonsmokers (HR 1.04, 95% CI 0.54 to 2.00, p = 0.903). Interaction testing showed heterogeneity in treatment effect for reinfarction (p = 0.002) and stent thrombosis (p = 0.018) according to smoking status. In conclusion, among patients with STEMI undergoing primary PCI, smoking status did not affect the adjusted risk of clinical events. Intracoronary abciximab bolus improved clinical outcomes by reducing the risk of death or reinfarction.