Coronary artery bypass grafting with bilateral internal thoracic arteries and without cardiopulmonary bypass: very long-term survival.

introductionCoronary artery bypass grafting (CABG) using bilateral internal thoracic arteries (BITA) without cardiopulmonary bypass (off-pump) has demonstrated improved mid-term survival with reduced perioperative risk. However, evidence regarding its long-term effectiveness and safety is lacking, particularly in Latin American populations.

objectivesTo describe long-term survival (20 years) in a consecutive cohort of patients undergoing exclusively off-pump CABG with BITA and to assess the impact of age, ventricular function, angina type, diabetic status, and body mass index (BMI) on survival. MATERIALS AND

methodsWe conducted a retrospective, open-cohort study of patients who underwent exclusively off-pump CABG with BITA between January 2003 and December 2023. Emergency surgeries, combined procedures, and patients with prior cardiac surgery were excluded. Follow-up ranged from at least 1 year to 20 years after surgery. Demographic data were obtained from medical records, and survival status was assessed through telephone contact. For the primary endpoint, survival tables and Kaplan-Meier curves were generated. Cox proportional hazards regression models were applied to compare time to death according to age, ventricular function, angina type, diabetic status, and BMI. Crude and adjusted hazard ratios (HR) with 95% confidence intervals (CI) were reported.

resultsA total of 4,495 patients were included during the study period, with a median follow-up of 6.3 years (interquartile range [IQR] 3-10). Of these, 95 patients reached 20 years of follow-up and 39 were followed for more than 20 years. Mean age was 64.07 years (SD 9.26), mean BMI 28.70 (SD 6.47); 91.6% (n = 4,120) were male, 28,2% (n = 1,269) were diabetic, and 48.7% (n = 2,182) presented with unstable angina. Overall survival was 70% (95% CI: 68-72%) at 10 years and 31% (95% CI: 28-34%) at 20 years. Among patients younger than 65 years, survival was 88% (95% CI: 85-89%) at 10 years and 60% (95% CI: 55-65%) at 20 years. Age ≥ 65 years and severe ventricular dysfunction were independently associated with higher postoperative mortality (adjusted HR 4.99; 95% CI: 4.33-5.75; p < 0.01 and adjusted HR 2.20; § 95% CI: 1.73-2.80; p < 0.01, respectively). Angina type was not an independent predictor of survival (adjusted HR 0.93; 95% CI: 0.81-1.06). Diabetes, both without obesity (adjusted HR 1.28; 95% CI: 1.10-1.48; p = 0.001) and with obesity (adjusted HR 1.35; 95% CI: 1.11-1.65; p < 0.01), was independently associated with increased mortality. Obesity without diabetes, however, was not (adjusted HR 1.05; 95% CI: 0.88-1.24; p = 0.603).

conclusionIn this 20-year retrospective cohort, off-pump CABG with BITA demonstrated high long-term survival in younger patients. Severe ventricular dysfunction and diabetes-particularly when combined with obesity-were independently associated with increased mortality. Neither obesity alone nor angina type were independent predictors of mortality.