One or Two Internal Thoracic Grafts? Long-Term Follow-up of 957 Off Pump Coronary Bypass Surgeries

Background:
The potential survival benefit of a bilateral internal thoracic artery grafting (BITA) in patients undergoing off pump surgery (OPCAB) is controversial due to the technical complexity of these operations. Our objective was to compare outcome of patients undergoing OPCAB with BITA to outcome of patients undergoing OPCAB with single internal thoracic artery (SITA) and saphenous vein grafts or radial artery .

Methods:
Five hundred and thirty five consecutive patients who underwent OPCAB BITA at our institute between 2000 and 2008, were compared with 422 who underwent OPCAB with SITA .

Results:
Female gender (20.9% vs. 36.0%, p .<0.001), diabetes (36.6% vs. 55.7%, p > 0.001) recent myocardial infarction (23.6% vs. 33.2%, p > 0.001), age 70+ years (41.1% vs. 49.8%, p = 0.001), peripheral vascular disease (26.1% vs.46.7%, p > 0.001) and chronic renal failure (7.9% vs. 15.9%, p > 0.001) were less frequent in the BITA group vs. the SITA group, respectively. The SITA group’s Euro-SCORE was significantly higher (7.62 vs. 5.46 BITA group, p = 0.001), while operative mortality (1.8% BITA vs. 2.8% SITA) and sternal wound infections (2% BITA vs. 2.1% SITA) were similar. The mean follow-up was 11.58 ± 3.49 years. The BITA group’s 10-year survival (Kaplan-Meier) was significantly better (72.2% vs. 55.1% SITA, , p > 0.001 log-rank test). Assignment to BITA was also associated with better propensity-adjusted survival (p = 0.001 vs. SITA, Cox model).

Conclusions:
This large cohort study suggests that long-term outcome for patients undergoing OPCAB is better with BITA grafting.