Abstract
BACKGROUND: Internal thoracic artery (ITA) use is a benchmark of quality in coronary artery bypass grafting (CABG), yet its value in contemporary practice among octogenarians remains uncertain. We compared mid-term major adverse cardiac events and all-cause mortality among octogenarians undergoing CABG with ITA plus saphenous vein grafts (SVGs) vs SVG-only. METHODS: We identified 13,925 octogenarians who underwent isolated first-time elective CABG with 2-4 grafts from 2015 to 2022 in the US Centers for Medicare and Medicaid database validated against individual clinical records: 12,280 received ITA+SVG and 1105 received SVG-only. The primary outcome was 6-year freedom from major adverse cardiac events (MACE) defined as death, myocardial infarction, or repeated revascularisation. The secondary outcome was 6-year all-cause mortality. Median follow-up time was 4.3 years (interquartile range [IQR] 4.2-4.5 years). Outcomes were compared in a Cox proportional hazards model after propensity matching across 28 covariates with an exact number of grafts. RESULTS: Patients receiving ITA+SVG were of similar age (81 years [IQR 80-83 years] vs 82 years [IQR 80-84 years]; P = 0.13) and less often female (24% vs 31.1%; P < 0.001). Propensity score matching yielded 1101 well matched pairs. Six-year freedom from MACE was 49.7% in the ITA+SVG group vs 48% in the SVG-only group (adjusted hazard ratio [aHR] 0.92, 95% confidence interval [CI] 0.79-1.06; P = 0.23). There was no difference in 6-year all-cause mortality (54.8% vs 52.7%; aHR 0.90, 95% CI 0.78-1.05; P = 0.19). CONCLUSIONS: Among octogenarians undergoing elective multivessel CABG, ITA use was not associated with improved 6-year freedom from MACE or all-cause mortality. These findings suggest that universal ITA-based quality metrics may need reassessment for octogenarians.