Benefits and risks of abciximab use in primary angioplasty for acute myocardial infarction: the Controlled Abciximab and Device Investigation to Lower Late Angioplasty Complications (CADILLAC) trial.

BACKGROUND

Trials of platelet glycoprotein IIb/IIIa inhibitors as adjuncts to primary percutaneous coronary intervention for acute myocardial infarction (MI) have shown improved early clinical and angiographic outcomes with treatment. However, variations in trial designs, modest sample sizes, and limited long-term follow-up have precluded these studies from being definitive.

METHODS AND RESULTS

As a prespecified secondary analysis of the CADILLAC trial, we compared early and late outcomes by abciximab assignment among 2082 patients randomized in an open-label, 2x2 factorial-design trial of primary stenting versus angioplasty and abciximab treatment (n=1052) versus no abciximab treatment (n=1030). Baseline characteristics were balanced between groups. Abciximab treatment was associated with a significant reduction in the composite end point of death, MI, ischemia-driven target-vessel revascularization (TVR), or disabling stroke at 30 days (4.6% versus 7.0%; relative risk, 0.65; 95% CI, 0.46 to 0.93; P=0.01). Subacute thrombosis also was significantly reduced with abciximab treatment. At 12 months, however, rates of the composite end point did not differ significantly (18.4% for controls versus 16.9% for abciximab-treated patients; relative risk, 0.92; 95% CI, 0.76 to 1.10; P=0.29), reflecting a decrease in the relative difference in TVR rates (ie, no effect of abciximab on reducing restenosis). In an angiographic substudy (n=656), myocardial salvage, restenosis, and infarct-artery reocclusion at 7 months were unaffected by abciximab treatment. There was no significant interaction between stenting and abciximab treatment.

CONCLUSIONS

Adjunctive abciximab treatment during primary percutaneous coronary intervention significantly enhanced 30-day event-free survival, predominantly by reducing ischemia-driven TVR. Abciximab treatment did not affect the composite end point at 1 year, reflecting a lack of effect on restenosis.