The balance between short-term and long-term outcomes of bilateral internal thoracic artery skeletonization in coronary artery bypass surgery: a propensity-matched cohort study

OBJECTIVES: There is growing interest in the use of bilateral internal thoracic arteries (BITAs) for myocardial revascularization. This study sought to compare the balance between early benefits and long-term outcomes of skeletonized or non-skeletonized conduits and to determine whether differences in outcomes are affected by other patient risk factors. METHODS: BITAs were used in 1504 cases with either SK or NSK conduits. Propensity matching was completed using 22 covariates identifying 441 pairs of patients. The primary outcomes are the sternal wound infection in the short term and the composite outcome of all-cause mortality, myocardial infarction, revascularization and congestive heart failure. Outcomes were assessed using paired analysis techniques and Cox proportional hazards regression models stratified using the matched pairs. RESULTS: Incidences of in-hospital mortality and perioperative myocardial infarction were similar in both groups. There were fewer sternal wound infections in the SK group (5.4 vs 9.1%, P = 0.033). Homogeneity testing of the relative risk estimates confirmed that there was a protective effect of skeletonization in men that was not demonstrated in women (P = 0.020). SK had a protective effect in diabetics not seen in non-diabetics (P = 0.048). The composite outcome of all-cause mortality, myocardial infarction, revascularization and congestive heart failure at a median of 5.6 years was comparable in both groups (hazard ratio 0.81, 95% confidence interval 0.57-1.15). CONCLUSION: Skeletonization results in better perioperative outcomes and comparable cardiac outcomes in patients undergoing BITA with the greatest benefit in men and patients with chronic obstructive pulmonary disease.