Long-term outcomes of patients receiving right internal thoracic artery or radial artery as a second arterial conduit. A propensity score matching study

Objective: This study aimed to compare the long-term outcomes in propensity matched patients receiving right internal thoracic artery(RITA) or radial artery(RA) as second arterial conduit during coronary artery bypass grafting(CABG) with internal thoracic artery to the left anterior descending artery(LAD). Methods: In this retrospective study, propensity score matching was performed including 1198 patients from 3 centers resulting in 389-pairs who received either RITA or RA. Results: In the matched cohort, median follow-up time was 7.53 years(interquartile range, 4.35–11.81). Survival probabilities at 5, 10 and 15-years were 93.8% versus 94.5%, 81.2% versus 76.2% and 63.2% vs 62.5% in the RITA and RA groups, respectively(HR: 1.11; 95%CI;0.80–1.53; P = 0.533) Freedom from MACCE in the matched cohort at 5, 10 and 15-years were 92.0% versus 93.7%, 75.0% versus 73.8%, 72.2% and 46.9% vs 47.2% in the RITA and RA groups, respectively(HR: 0.96; 95%CI;0.74–1.26; P = 0.774). Subgroup analyses of the matched cohort showed comparable long-term outcomes in terms of MACCE at follow-up in patients with age older than 65-years, obese patients, diabetics, female patients and with impaired EF. As for target vessel revascularization, RITA and RA had comparable outcomes in terms of MACCE when the conduit was used to graft either the left coronary system or the right coronary system. Conclusions: The use of RITA or RA as second arterial conduit during CABG with internal thoracic artery to the LAD is safe and associated with comparable long-term clinical outcomes. The choice of optimal second arterial conduit should be guided mainly by patients' characteristics and surgeons' preferences.