Abstract 1998: Short- and Long-Term Effects of Abciximab in Patients Undergoing Primary Stenting for Acute Myocardial Infarction: Meta-Analysis of Randomized Trials

Background: Both short- and long-term benefits of abciximab therapy in primary angioplasty for acute myocardial infarction (AMI) have been reported. However, primary stenting is the preferred treatment of AMI and conflicting data exists on the effect of abciximab therapy on outcomes following primary stent treatment of AMI. We therefore performed a meta-analysis of all randomized trials of abciximab in primary stenting for AMI for which there was short-term (30-day) and long-term (≥ 1 year) follow-up. Methods: We searched the MEDLINE and Cochrane databases using the following key words: stent, acute myocardial infarction, abciximab and randomized trial. Four studies (ISAR-2, ADMIRAL, CADILLAC and ACE) were included in this analysis. The incidence of the individual end points of death, reinfarction and target vessel revascularization (TVR) at 30 days and at long-term follow-up was extracted. Follow-up data was available at 1 year for ACE and CADILLAC, at 3 years for ADMIRAL and 5 years for ISAR-2. A random effects model was used to calculate the combined odds ratio (OR) of reinfarction, TVR and mortality associated with the use of abciximab. Results: The 4 trials enrolled 2137 patients of whom 1074 were randomized to abciximab and 1063 to placebo. Long-term follow up was available for 2107 patients, 1064 in the abciximab group and 1043 in the control group. At 30 days, abciximab resulted in a significant reduction in the odds of TVR (OR 0.45, 95% CI, 0.27–0.75, P=0.003) and a non-significant reduction in the odds of reinfarction (OR 0.43, 95% CI, 0.18–1.0, P=0.06) but no reduction in 30-day mortality (OR 0.78, 95% CI, 0.47–1.2, P=0.34). During long-term follow up, abciximab treatment resulted in a non-significant reduction in the risk of TVR (OR 0.77, 95% CI 0.58–1.0, P=0.06) but no reduction in reinfarction (OR 0.58, 95% CI, 0.3–1.1, P=0.12) or mortality (OR 0.90, 95% CI, 0.48–1.6, P=0.74). Conclusions: Abciximab resulted in a significant reduction in TVR at 30 days that diminished over time. We were unable to demonstrate a significant reduction in reinfarction or mortality at 30 days or at 1–5 years. These results suggest the need for an appropriately powered clinical trial to define the role of abciximab during primary stenting for AMI.