Sternal wound infections in patients after coronary artery bypass graftingusing bilateral skeletonized internal mammary arteries

Objectives This study evaluated the risks of sternal wound infections in pa tients undergoing myocardial revascularization using bilateral skeletonized internal mammary arteries (IMAs). Background The skeletonized IMA is longer than the pedicled one, thus provi ding the cardiac surgeon with increased versatility for arterial myocardial revascularization without the use of vein grafts. It is isolated from the chest wall gently with scissors and silver clips, and no cauterization is e mployed. Presentation of collateral blood supply to the sternum and avoidan ce of thermal injury enable more rapid healing and decrease the risk of ste rnal wound infection. Methods From April 1996 to August 1997, 545 patients underwent arterial myo cardial revascularization using bilateral skeletonized IMAs. The right gast roepiploic artery was used in 100 patients (18%). The average age of the pa tients was 65 years; 431 (79%) were men and 114 (21%) were women; 179 (33%) were older than 70 years of age; 166 (30%) were diabetics. The average num ber of grafts was 3.2 per patient. Results The 30-day operative mortality rate was 2% (n = 11). There were six perioperative infarcts (1.1%) and six strokes (1.1%); 9 patients had stern al infection (1.7%) and 15(2.8%) had superficial infection. Risk factors fo r sternal infection were chronic obstructive pulmonary disease and emergenc y operation. Superficial sternal wound infections were more common in women and in patients with chronic obstructive pulmonary disease, renal failure, or peripheral vascular disease. The 1-year actuarial survival rate was 97% . Two of the six late deaths were not cardiac-related. Late dehiscence occu rred in three patients (0.6%). The death rate (early and late) of patients with any sternal complication was higher than that of patients without thos e complications (33% vs. 2.7%). Conclusions Routine arterial myocardial revascularization using bilateral s keletonized IMAs is safe, and postoperative morbidity and mortality rates a re low, even in elderly patients and those with diabetes. Chronic obstructi ve pulmonary disease and emergency operations were found to be associated w ith an increased risk of sternal infections, and the authors recommend avoi ding the use of bilateral skeletonized IMAs in patients with these preopera tive risk factors.