Are two internal thoracic grafts better than one in patients with peripheral vascular disease?

Background The use of two bilateral internal thoracic artery grafting (BITA) was shown to lead to survival benefit. However, operators are reluctant to use BITA with peripheral vascular disease (PVD) because of concerns of increased rates of sternal wound infection and lack of studies supporting survival benefit compared with single internal thoracic artery (SITA) grafting. The aim of this study is to compare outcome BITA grafting versus of SITA and vein grafts in PVD patients. Patients and methods Six hundred and twenty-one PVD patients who underwent BITA between 1996 and 2011 were compared with 372 patients who underwent SITA. Results SITA patients were older and more likely more likely to have comorbidities (female, insulin-dependent diabetes, chronic obstructive lung disease, congestive heart failure, previous coronary artery bypass grafting, renal insufficiency, cerebrovascular disease, and emergency operation). Operative mortality (5.1 vs. 4.5%, in the SITA and BITA, respectively, P=0.758), rate of sternal wound infection (5.1 vs. 3.9%, P=0.421), and strokes (4.8 vs. 7.4%, P=0.141) were not significantly different between groups. BITA patients did not have significantly better 10-year survival (52.6 vs. 45.9%, P=0.087) and after propensity score matching (302 well-matched pairs), BITA was not associated with improved survival (hazard ratio: 0.902; 95% confidence interval: 0.742-1.283; P=0.784) (Cox model). Conclusion The routine use of BITA versus SITA in PVD patients does not improve long-term survival. Selective use of BITA in lower risk patients might unmask the benefits of BITA.