Long-term effect of dual antiplatelet treatment after off-pump coronary artery bypass grafting.

OBJECTIVES: Recent studies have found increased long-term cardiovascular morbidity after off-pump coronary artery bypass surgery (OPCAB). We evaluated the efficacy and safety of dual antiplatelet therapy (DAT) in the prevention of cardiovascular events at two years after OPCAB surgery.

METHODS: Retrospective study that included all patients that underwent OPCAB surgery in our institution between 2009 and 2010. Single or dual antiplatelet therapy was initiated at hospital discharge, and its effect in patients' prognosis was analyzed. Follow-up was conducted by telephone and using the hospital databases. The primary end-point was the composite of acute coronary syndrome (ACS), revascularization, stroke, or cardiovascular death.

RESULTS: The study included 237 patients divided into: (A) 128 patients who received single antiplatelet therapy and (B) 109 patients who received dual antiplatelet therapy. The mean follow-up was 23.85 months (standard deviation 0.5 months). 13.9% of patients had a primary end-point event. Patients in group A had a higher event rate compared with group B (18.8% vs. 8.3%, p = 0.02), with a significant reduction in hospital readmissions for ACS (10.9% vs. 3.7%, p = 0.035). In the multivariate analysis, dual antiplatelet therapy was an independent protective factor in the occurrence of events (hazard ratio = 0.395, 95% CI, 0.176 to 0.885, p = 0.024). There were no significant differences between the two groups with respect to bleeding events.

CONCLUSION: Dual antiplatelet therapy after OPCAB surgery is associated with a decrease in the appearance of new cardiovascular events, due to a reduction in the number of hospital readmissions for ACS.