The Incremental Value of Three or More Arterial Grafts in CABG: The Effect of Native Vessel Disease.

Background: We investigated whether extended arterial grafting with three or more arterial grafts in patients with a left internal thoracic artery to left anterior descending artery graft improves survival in coronary artery bypass graft surgery patients and whether its effects will depend on the extent of coronary artery disease; specifically three-vessel disease (3VD) versus two-vessel disease (2VD).

Methods: Fifteen-year mortality was analyzed in 11,931 patients with multivessel disease and primary isolated left internal thoracic artery to left anterior descending artery coronary artery bypass graft surgery with 2 or more grafts. Patients were aged 64.3 ± 10.5 years; 3,484 (29.2%) were women; 2,532 (21.2%) had 2VD and 9,399 (78.8%) had 3VD. Patients were grouped into one single-artery group (n = 6,782, 56.9%; reference group), and two multiple artery groups: two arteries (n = 3,678, 30.8%) and three arteries (n = 1,471, 12.3%). Long-term survival was compared by Kaplan-Meier estimates. Risk-adjusted mortality hazard ratio (HR) with 95% confidence interval (CI) were derived by covariate adjusted Cox regression to quantify multiple artery effects versus one artery in the overall cohort and separately among patients with 2VD and 3VD.

Results: Radial artery (94%) and right internal thoracic artery (6%) conduits were used for additional arterial grafts. For the entire multivessel cohort, increasing number of arterial grafts was associated with incrementally improved 15-year survival (two arteries HR 0.85, 95% CI: 0.78 to 0.92; three arteries HR 0.75, 95% CI: 0.65 to 0.85). The three arteries versus two arteries comparison was consistent, even if not significant (HR 0.89, 95% CI: 0.77 to 1.03). The benefits derived from additional arterial grafts were more pronounced in case of 3VD (two arteries HR 0.84 95% CI: 0.76 to 0.92; three arteries HR 0.73, 95% CI: 0.63 to 0.84), without survival benefit with 2VD.

Conclusions: Our results support the use of extended arterial grafting to maximize long-term coronary artery bypass graft surgery patient survival, especially for 3VD patients.