Sternal Wound Complications of Coronary Artery Bypass Grafting Using Bilateral Internal Mammary Arteries

Abstract

The use of bilateral internal mammary arteries (BIMA) in coronary artery bypass grafting (CABG) confers greater freedom from myocardial infarction, angina recurrence, repeat intervention and survival benefit. The main disadvantage of BIMA use is the risk of sternal dehiscence and deep sternal infection from ischemia. This has been challenged over the years. The objectives of this descriptive study were: to determine the frequency of patients who developed sternal wound complications, and describe the sternal complications seen, their treatment and duration. A secondary objective of this study was to determine factors associated with increased risk of sternal wound morbidity. Methods: Forty-five (45) patients who underwent CABG using BIMA as performed by the authors in 3 medical centers from January 2007 until May 2012 were included. The preoperative and postoperative characteristics and outcome were recorded. Results: The mean age was 53.2 years (range: 37-71). All except one patient were males. No patient developed sternal dehiscence or deep sternal infection – 0/45. Eight patients (17.8%) developed minor sternal wound morbidities. These morbidities included skin dehiscence, superficial sternal wound infection and foreign body granuloma. All the sternal wound morbidities were treated as outpatients and majority resolved within the first postoperative month. Multiple logistic regression analysis showed that diabetes mellitus was a risk factor for minor sternal wound morbidity with an adjusted odds ratio of 11.4 (95% CI: 1.4 – 96.1). Conclusion: The use of BIMA during CABG was not associated with sternal wound dehiscence or mediastinitis. Diabetes mellitus was a risk factor for minor sternal wound morbidity Key words: Coronary artery bypass, internal mammary – coronary, anastomosis, complication, surgical wound infection, diabetes