Composite outcomes in coronary bypass surgery versus percutaneous intervention

Recent observational studies show that patients with multivessel coronary disease have a long-term survival advantage with coronary artery bypass grafting (CABG) compared with percutaneous coronary intervention (PCI). Important nonfatal outcomes may also affect optimal treatment recommendation.

CABG was compared with percutaneous catheter intervention by using a composite of death, myocardial infarction (MI), or stroke. Medicare patients undergoing revascularization for stable multivessel coronary disease from 2004 through 2008 were identified in national registries. Short-term clinical information from the registries was linked to Medicare data to obtain long-term follow-up out to 4 years from the time of the procedure. Propensity scoring with inverse probability weighting was used to adjust for baseline risk factors.

There were 86,244 CABG and 103,549 PCI patients. The mean age was 74 years, with a median 2.67 years of follow-up. At 4 years, the propensity-adjusted adjusted cumulative incidence of MI was 3.2% in CABG compared with 6.6% in PCI (risk ratio, 0.49; 95% confidence interval, 0.45 to 0.53). At 4 years, the cumulative incidence of stroke was 4.5% in CABG compared with 3.1% in PCI patients (risk ratio, 1.43; 95% confidence interval, 1.31 to 1.54). This difference was primarily due to the higher 30-day stroke rate for CABG (1.55% vs 0.37%). For the composite of death, MI, or stroke, the 4-year adjusted cumulative incidence was 21.6% for CABG and 26.7% for PCI (risk ratio, 0.81; 95% confidence interval, 0.78 to 0.83).

The 4-year composite event rate of death, MI, and stroke favored CABG, whereas the risk of stroke alone favored PCI.