Bilateral internal mammary artery grafts, mortality and morbidity: an analysis of 1 526 360 coronary bypass operations
- 1Department of Cardiothoracic Surgery, The Mount Sinai Medical Center, New York, New York, USA
- 2Department of Cardiothoracic Surgery, The Mount Sinai School of Medicine, New York, New York, USA
- Correspondence to Dr Joanna Chikwe, Department of Cardiothoracic Surgery, Mount Sinai Medical Center, 1190 Fifth Avenue, New York, NY 10029, USA;
- Received 17 January 2013
- Revised 18 February 2013
- Accepted 19 February 2013
- Published Online First 20 March 2013
Objectives The objective of this study was to investigate the impact of bilateral internal mammary artery (BIMA) on early outcomes after coronary artery bypass grafting.
Design Retrospective database analysis.
Setting US hospitals.
Patients 1 526 360 patients (mean age 65 years, 73% male) from the Nationwide Inpatient Sample from 2002–2008 who underwent isolated coronary artery bypass grafting with at least one internal mammary artery.
Interventions Single versus BIMA bypass grafting.
Main outcome measures Inhospital mortality, deep sternal wound infection (DSWI).
Results The rate of BIMA use was 3.9%. Use of BIMA was independently associated with slightly lower inhospital mortality (unadjusted rate 1.1% vs 1.7%, adjusted OR 0.86, 95% CI 0.79 to 0.93). The DSWI rate was 1.4%. The independent predictors of DSWI were female gender (OR 1.06), congestive heart failure (OR 6.22), chronic pulmonary disease (OR 1.57), obesity (OR 1.17), diabetes mellitus (OR 1.04; OR 1.51 with chronic complication) and chronic renal failure (OR 2.13; OR 2.63 with dialysis). The use of BIMA was not an independent predictor of DSWI (OR 1.03, 95% CI 0.96 to 1.10). BIMA was associated with higher incidence of DSWI in patients with chronic complications of diabetes mellitus (OR 1.90, 95% CI 1.51 to 2.41).
Conclusions BIMA grafting is associated with increased risk of DSWI only in patients with severe, chronic diabetes. The incremental morbidity and mortality of DSWI does not justify denial of BIMA in the majority of patients.