Impact of Incomplete Revascularization on Long-term Survival Based on Revascularization Strategy

Background: This study investigated the impact of complete revascularization (CR) and incomplete revascularization (IR) on long-term survival in patients undergoing isolated coronary artery bypass grafting (CABG) using multiple arterial graft (MAGs) or a single artery with saphenous vein grafts (SAGs). Methods: Between January 2006 and December 2020, 12,625 patients underwent CABG and were divided into 4 groups: MAG CR (n = 1066), MAG IR (n = 286), SAG CR (n = 8360), and SAG IR (n = 2913). Inverse probability of treatment weighting based on the generalized propensity score was used to minimize imbalance between the groups. Results: In the weighted cohort, median follow-up time was 8.35 years (interquartile range, 5.01-11.6 years). MAG CR was associated with similar long-term survival compared with MAG IR (hazard ratio [HR], 0.79; 95% CI, 0.60-1.03; P = .084). SAG CR was associated with improved long-term survival compared with SAG IR (HR, 0.67; 95% CI, 0.52-0.84; P = .01). MAG CR was associated with better long-term survival compared with SAG CR (HR, 0.45; 95% CI, 0.35-0.57; P < .001). Moreover, MAG IR was protective compared with SAG IR (HR, 0.62; 95% CI, 0.45-0.85; P = .033). Additional analysis was performed comparing perfect CR vs imperfect CR vs IR in MAG and SAG patients, separately. In the weighted sample of MAG, there were no differences in the long-term survival between perfect CR, imperfect CR, and IR. However, in the weighted sample of the SAG cohort, SAG perfect CR was associated with improved survival compared with SAG imperfect CR (HR, 0.81; 95% CI, 0.0.72-0.92; P = .001). Whereas, SAG perfect and imperfect CR were both associated with improved survival compared with SAG IR (HR, 0.51; 95% CI, 0.0.35-0.87; P = .006 and HR, 0.72; 95% CI, 0.64-0.82; P < .001), respectively. Conclusions: MAG CR is associated with better survival compared with SAG CR. If IR is inevitable, patients with MAG IR had better long-term survival compared with patients receiving SAG IR. Moreover, similar long-term survival is observed whether perfect CR, imperfect CR, or IR is achieved in the MAG population but not in SAG patients.