Does bilateral ITA grafting increase perioperative complications? Outcome of 4462 patients with bilateral versus 4204 patients with single ITA bypass.

Objective: Superior patency of internal thoracic artery (ITA) grafting to saphenous veins is conclusive. The aim of the present study was to compare the early outcome of patients receiving either bilateral ITA (BITA) or single ITA (SITA) grafts and to identify risk factors for perioperative complications, such as obesity, diabetes mellitus, or advanced age.

Methods: All 8666 patients with isolated coronary artery bypass grafting (CABG, including emergent cases or redos) operated between January 1994 and June 2004 receiving either BITA (n=4462) or SITA (n=4204) grafting were analyzed retrospectively. Demographic data were comparable for both groups concerning mean age (65.3+/-9.4 years vs 64.9+/-9.3 years), range (35-89 years (p=0.05)), diabetes incidence (29.3% vs 2.6% (p=0.08)), dialysis-dependent renal failure (0.7% vs 0.6% (p=0.4)), preoperative ejection fraction (EF) mean (61.8% vs 61.2% (p=0.07)) but not for gender (80.4% vs 76.7% males (p=0.00)), body mass index (BMI) mean (27.2+/-3.6 vs 26.9+/-3.5 (p=0.00)), COPD (7.0% vs 8.5% (p=0.00)), and hyperlipidemia (78.3% vs 74.3% (p=0.00)). In the BITA group, right ITA (RITA) was directed preferentially to the left anterior descending artery (LAD), left ITA (LITA) to the lateral wall. In the SITA group, the LAD was revascularized with the left ITA. Additional bypasses were performed with saphenous vein grafts (SVG).

Results: The number of anastomoses was higher in the BITA group (3.8+/-0.9 vs 3.1+/-0.9 (p=0.00)); therefore, duration of surgery (mean: 189+/-46.3 min vs 164+/-46.2 min) and cross-clamp time (62.0+/-17.9 min vs 51.0+/-18.0 min) significantly prolonged (p=0.00). Incidence of rethoracotomy due to bleeding (2.9% vs 0.6%; p=0.00) or sternal refixation with (0.7% vs 0.2%; p=0.00) or without infection (1.4% vs 0.6%; p=0.00) was higher in the BITA group, strongly associated with diabetes mellitus and duration of surgery but not with BMI>27. Thirty-day mortality revealed 2.6% versus 3.2% (p=0.1) but was significantly lower for diabetic patients in the BITA group (3.1% vs 4.7%; p=0.00).

Conclusions: CABG using both ITAs can be performed routinely with good clinical results and low mortality. Compared with single ITA grafting, sternal and bleeding complications were slightly increased. Diabetes mellitus, BITA grafting, duration of surgery but not obesity or COPD could be identified as independent risk factors for sternal complications. Dialysis-dependent renal failure, EF<30%, emergent cases, and the absence of BITA grafting were predictors for increased perioperative mortality.