Abstract 13183: Dual Antiplatelet Therapy in Patients With Aspirin Resistance Following Coronary Artery Bypass Grafting
Background: Coronary artery bypass grafting (CABG) is pivotal in the contemporary management of complex coronary artery disease. Interpatient variability to antiplatelet agents, however, harbors potential to compromise the revascularization benefit by increasing the incidence of adverse events. Little is known about the impact of dual antiplatelet therapy (dAPT) in aspirin-resistant patients after CABG.
Methods: This prospective randomized trial evaluated 208 patients with aggregometry-documented aspirin resistance after CABG. Patients were randomized to either continue on their current antiplatelet regime of 300 mg of aspirin (control group), or to undergo intensified platelet inhibition with dual antiplatelet therapy (dAPT group; 300 mg aspirin+75 mg clopidogrel).
The primary endpoint was a composite MACCE outcome (all-cause death, non-fatal MI, stroke or cardiovascular hospitalization) at 6-month follow up. Bleeding events and individual MACCE components were recorded as secondary endpoints.
Results: Baseline patient characteristics were similar between the two groups (Table 1). The incidence of MACCE was 6% in the dAPT and 11% in the control group (P=0.21). The secondary composite endpoint of stroke/MI/death was observed in 3% in dAPT and 8% in the control group (P=0.13). Bleeding events occurred with similar frequency between the groups (P=0.41).
Conclusions: Intensifying platelet inhibition in aspirin resistant CABG patients did not reliably reduce the incidence of the primary endpoint. A non-significant reduction in the incidence of the composite endpoint of stroke/MI/death was observed with dual antiplatelet therapy. The cumulative platelet inhibition strategy did not come at the cost of increasing bleeding events.
- © 2013 by American Heart Association, Inc.