The following is a summary of “Vein Graft Use and Long-Term Survival Following Coronary Bypass Grafting,” published in the February 2023 issue of Cardiology by Shih, et al.
It had been established that placing at least one arterial graft during coronary artery bypass grafting (CABG) improved survival, however, it was unclear how much revascularization with saphenous vein grafting (SVG) affected survival. For a study, researchers set out to investigate if having a surgeon who uses vein grafts liberally was associated with better survival in patients having single arterial graft CABG (SAG-CABG).
The study examined the effects of SAG-CABG on Medicare beneficiaries between 2001 and 2015. It was retrospective and observational study. Conservative (≥1 SD below mean), moderate (≥1 SD of mean), and liberal (≥1 SD above mean) surgeons were classified according to the number of SVG used per SAG-CABG. Using Kaplan-Meier analysis, long-term survival was calculated and compared between surgeon groups before and after augmented inverse-probability weighting.
Between 2001 and 2015, 1,028,264 Medicare beneficiaries had SAG-CABG procedures (mean age 72.0 ± 7.9 years, 68.3% male). Utilization of 1- and 2-vein SAG-CABG rose throughout time, whereas 3- and ≥4-vein SAG-CABG utilization declined (P< 0.001). The average number of vein grafts used by conservative surgeons per SAG-CABG was 1.7± 0.2, but the average number of vein grafts used by liberal surgeons per SAG-CABG was 2.9± 0.2. Patients who underwent SAG-CABG with liberal vs. conservative vein graft users showed no difference in median survival, according to weighted analysis (adjusted median survival difference 27 days).
A conservative approach to vein graft utilization was justified given that there is no correlation between a surgeon’s proclivity for using vein grafts and long-term survival among Medicare beneficiaries following SAG-CABG.