A second arterial conduit to the circumflex circulation significantly improves survival after coronary artery bypass surgery.

Objectives: Conventional coronary artery bypass surgery involves the use of a single left internal mammary artery to the left anterior descending artery and saphenous vein grafts reserved for other sites. This retrospective propensity-matched study investigated the impact of a second arterial conduit to the left-sided circulation on early and long-term survival after coronary artery bypass surgery.

Methods: Data were retrospectively collected from 2004 to 2014 for all revascularizations with at least 1 arterial and/or 1 venous graft to the circumflex circulation, in addition to an internal mammary artery to the left anterior descending artery. Propensity-matched groups were created based on baseline characteristics. Hazard functions were estimated using Cox multivariable regression, and the Kaplan-Meier survival curves were compared between the matched cohorts.

Results: A total of 1226 patients with a venous conduit to the left-sided circulation were successfully matched to an equal number of patients with an arterial conduit. Regression analysis identified a second arterial conduit, logistic European System for Cardiac Operative Risk Evaluation score (EuroSCORE), pulmonary disease, left ventricular ejection fraction, New York Heart Association (NYHA) Class and previous myocardial infarction as significant predictors of survival. A second arterial graft to the left circumflex circulation was a predictor of improved survival (hazard ratio 0.64, 95% confidence interval 0.51-0.80; P < 0.001). There were significant early and late survival benefits (arterial vs venous: 98.2% vs 96.3%, P = 0.003 at 1 year; 82.4% vs 62.2%, P < 0.001 at 10 years) from a second arterial conduit to the circumflex circulation.

Conclusions: There are significant early and late incremental survival benefits from a second arterial conduit to the circumflex circulation.