Outcomes associated with the use of secondary prevention medications after coronary artery bypass graft surgery

Background. Secondary prevention medications are beneficial after acute coronary syndromes, but these benefits are less clear after coronary artery bypass graft surgery. We investigated whether greater use of secondary prevention medications after coronary artery bypass graft surgery is associated with improved clinical outcomes. Methods. Patients undergoing coronary artery bypass graft surgery in the PREVENT IV trial (n = 2970) were surveyed for use of antiplatelet agents, beta-blockers, angiotensin-converting enzyme inhibitors or angiotensin receptor blockers, and lipid-lowering agents after hospital discharge and at 1 year. Patients were categorized based on their percentage use of indicated medications after hospital discharge. Cox modeling was used to determine the association between medication use categories and rates of death or myocardial infarction through 2 years after adjustment for clinical factors, the number of indicated medications, and treatment propensity. Results. Rates of use of antiplatelet agents and lipid-lowering agents were high at discharge and at 1 year, but use of beta-blockers and angiotensin-converting enzyme inhibitors or angiotensin receptor blockers was suboptimal. There was a stepwise association between medication use at discharge and patient outcomes (p for trend = 0.014). Patients taking 50% or less of indicated medications at discharge had a significantly higher 2-year rate of death or myocardial infarction (8.0% versus 4.2%; adjusted hazard ratio, 1.69; 95% confidence interval, 1.12 to 2.55; p = 0.013) than those taking all indicated medications. Conclusions. Greater use of indicated secondary prevention medications after coronary artery bypass graft surgery is associated with a lower 2-year rate of death or myocardial infarction. These data underscore the importance of appropriate secondary prevention measures to improve long-term clinical outcomes after coronary artery bypass graft surgery.