Effectiveness of radial artery–based multiarterial coronary artery bypass grafting: Role of body habitus

Abstract

Background: The multiarterial grafting survival advantage noted in the overall population undergoing coronary artery bypass grafting is not well defined in the obese. We investigated the early to late survival effects of the radial artery in left internal thoracic artery–based multiarterial bypass grafting (radial artery-multiarterial bypass grafting) versus single arterial bypass grafting (left internal thoracic artery-single arterial bypass grafting) in obese patients. Methods: We analyzed 15-year Kaplan–Meier survival in 6102 patients receiving primary, left internal thoracic artery–based coronary artery bypass grafting with 2 or more grafts divided into body mass index groups: nonobese (<30 kg/m2) and all-obese, comprised of mildly obese (30-35 kg/m2) and morbidly obese (>35 kg/m2). Risk-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of radial artery-multiarterial bypass grafting versus left internal thoracic artery-single arterial bypass grafting were derived via Cox regression and applied separately for early (<0.5 years), intermediate (0.5-5 years), and late (5-15 years) follow-up in each body mass index cohort. Propensity score matching between radial artery-multiarterial bypass grafting and left internal thoracic artery-single arterial bypass grafting cohorts within the body mass index groups was performed as a corroborating analysis. Results: Radial artery-multiarterial bypass grafting was more frequently used in obese patients who were younger (62 ± 10 years; mild/morbid: 45.4%/54.4% radial artery-multiarterial bypass grafting) compared with nonobese patients (66 ± 10 years; 37.4% radial artery-multiarterial bypass grafting). Unadjusted 15-year survival was significantly better for radial artery-multiarterial bypass grafting in all body mass index groups. Multivariate analysis showed a survival benefit of radial artery-multiarterial bypass grafting over the entire 0- to 15-year study period in the all-obese cohort (HR, 0.85; 95% CI, 0.74-0.98) and was more pronounced in the mildly obese (HR, 0.79; 95% CI, 0.66-0.96) versus morbidly obese (HR, 0.88; 95% CI, 0.69-1.13). The radial artery-multiarterial bypass grafting survival benefit was realized between 0.5 and 5 years postoperatively and was comparable for all-obese (HR, 0.69; 95% CI, 0.51-0.94) and nonobese (HR, 0.68; 95% CI, 0.52-0.88) groups. Propensity score matching was confirmatory. Conclusions: Radial artery-multiarterial bypass grafting confers a long-term survival advantage in both obese and nonobese patients. © 2018 The American Association for Thoracic Surgery