Bilateral Internal Mammary Artery Grafting and Risk of Sternal Wound Infection: Evidence From Observational Studies

Background. The advantageous survival outcome of bilateral internal mammary artery grafting (BIMA) has been well established. However, this meta-analysis aims to make clear whether BIMA grafting increases the risk of sternal wound infection (SWI) when compared with single internal mammary artery grafting (SIMA). Methods. A literature search was performed in PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials. The observational studies reporting a comparison between SIMA and BIMA were included. The outcome of interest was the risk of SWI. Literature search, data extraction, and quality assessment were performed. Sensitivity and publication bias were also assessed in this research. Results. We identified 4,701 titles and included 32 studies finally. The meta-analysis showed that the risk of SWI in the BIMA group was higher (relative risk [RR] 0.62, 95% confidence interval [CI] 0.55 to 0.71) than that in the SIMA group. Moreover, BIMA grafting was also associated with a higher risk of SWI in diabetic patients (RR 0.65, 95% CI 0.52 to 0.81) as well as elderly patients (RR 0.45, 95% CI 0.33 to 0.62). When skeletonization technique was adopted, the risk of SWI in BIMA patients was just a little higher than that in SIMA patients, but the difference did not reach statistical significance (RR 0.84, 95% CI 0.54 to 1.31). Conclusions. The BIMA grafting increases the risk of SWI when compared with SIMA grafting. This adverse effect further extends to diabetic and elderly patients. As regarding the method of procurement, skeletonized BIMA is safe and effective, thus it should be the procedure recommended. (C) 2013 by The Society of Thoracic Surgeons