A single sequential snake saphenous vein graft versus separate left and right vein grafts in coronary artery bypass surgery: a population-based cohort study from the SWEDEHEART registry†.

Abstract

Our goal was to compare short- and midterm outcomes after coronary artery bypass grafting (CABG) using 2 different revascularization strategies.A total of 6895 patients were included who had CABG in Sweden from 2009 to 2015 using the left internal mammary artery to the left anterior descending artery and either a single sequential saphenous vein graft connecting the left and right coronary territories to the aorta (snake graft, n = 2122) or separate vein grafts to both territories (n = 4773). Data were obtained from the Swedish Web System for Enhancement of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies (SWEDEHEART) and the Swedish Patient Registry. The groups were compared using adjusted logistic regression for short-term (30-day) and Cox regression and flexible parametric survival models for midterm outcomes. Primary outcome was a composite of all-cause mortality, myocardial infarction (MI), reangiography and new revascularization. The median follow-up time was 35 months.At 30 days, the incidences of the composite end point [odds ratio (OR) 1.31, 95% confidence interval (CI) 1.03-1.68; P = 0.03] and reangiography (OR 1.51, 95% CI 1.07-2.14; P = 0.02) were higher in the snake group. There was also a trend towards higher mortality (OR 1.47, 95% CI 0.97-2.22; P = 0.07). The event rates during the complete follow-up period were 6.5 (5.9-7.2) and 5.7 (5.3-6.1) per 100 person-years for the snake group and the separate vein group, respectively. At the midterm follow-up, no significant difference between the groups could be shown for the composite end point [hazard ratio (HR) 1.08, 95% CI 0.95-1.22; P = 0.24], mortality (HR 0.95, 95% CI 0.79-1.14; P = 0.56), MI (HR 1.11, 95% CI 0.88-1.41; P = 0.39) or new revascularization (HR 1.19, 95% CI 0.94-1.50; P = 0.15), whereas reangiography remained more common in the snake group (HR 1.25, 95% CI 1.05-1.48; P = 0.01).Snake grafts were associated with a higher rate of early postoperative complications, possibly reflecting a more demanding surgical technique, whereas midterm outcomes were comparable. Based on these data, one strategy cannot be recommended over the other.