Is the radial artery associated with improved survival in older patients undergoing coronary artery bypass grafting? An analysis of a multicentre experience

Abstract

OBJECTIVES: Studies suggest that the radial artery (RA) may exhibit superior patency compared with the saphenous vein (SV). It is unclear whether older patients undergoing coronary artery bypass grafting (CABG) derive any survival benefit from the use of RAs. We sought to evaluate this using a multicentre database. METHODS: From 1995 to 2010, 6059 patients with three-vessel coronary artery disease underwent primary isolated CABG at 8 centres. A study cohort of 4006 patients was formed with 3220 (80%) receiving at least 1 RA to supplement a single in situ internal thoracic artery (RA group) while 786 (20%) received only veins to supplement a single ITA (SV group). In the RA group, bilateral RAs were used in 1418 (44%) cases, while total arterial revascularization was achieved in 1859 (58%). RAs were mostly grafted to the left circumflex and right coronary territories. Survival data were obtained using the National Death Index and propensity-score matching was used for risk adjustment. Separate propensity-score analyses were conducted for the 2149 patients (1645 RA, 504 SV) who were 70 years or older. RESULTS: Patients receiving RAs were younger (mean age in years RA: 68 ± 9.7 vs SV: 71 ± 7.9, P < 0.001) and less likely to have cerebrovascular disease, obstructive airways disease, myocardial infarction within 7 days and left-main coronary disease. At 30 days, RA patients experienced reduced unadjusted mortality (49 of 3220, 1.5% vs 25 of 786, 3.2%, P = 0.004). At 15 years, the RA group showed superior unadjusted survival (51 ± 1.1 vs 35 ± 1.9%, P < 0.001). After propensity-score matching of 507 patient pairs, there was comparable 30-day mortality between groups (RA: 9, 1.8 vs SV: 14, 2.8%, P = 0.41). However, at 15 years, the RA group still showed superior survival (42 ± 2.6 vs 35 ± 2.5%, P = 0.008). Among those 70 years and older (327 matched pairs), despite similar 30-day mortality (RA: 6, 1.8% vs SV: 10, 3.1%, P = 0.42), RA patients again exhibited improved survival (35 ± 3.3 vs 22 ± 2.8%, P = 0.004) at 15 years. CONCLUSIONS: This multicentre analysis suggests that the use of an RA is associated with a survival benefit in older patients undergoing CABG.