Aortic valve replacement and concomitant coronary artery bypass: assessing the impact of multiple grafts.

BACKGROUND: The impact of multivessel coronary artery disease and multivessel coronary artery bypass grafting on outcomes after combined aortic valve replacement and coronary artery bypass grafting (AVR-CABG) has not been sufficiently evaluated.

METHODS: We retrospectively reviewed all patients who underwent AVR-CABG at our institution between January 2000 and December 2004. Patients with any previous or concomitant procedures were excluded. The Kaplan-Meier method was used to calculate survival and freedom from postoperative repeat revascularization. Predictors of mortality were determined by Cox regression analysis.

RESULTS: The study cohort consisted of 233 AVR-CABG patients. Mean follow-up was 2.2 +/- 1.7 years with one patient lost to follow-up. Preoperative clinical characteristics were well-matched between patients who received one (n = 86), two (n = 81), or three or four (n = 66) bypass grafts. Operative mortality was 9.3%, 11.1%, and 7.6%, respectively (p = 0.76). Patients in all groups demonstrated significant improvement in New York Heart Association (NYHA) status (p < 0.01). Freedom from postoperative repeat revascularization for all patients after five years was 96.8% and did not differ among groups (p = 0.93). Five-year survival for each group was 63.6%, 72.4%, and 63.9%, respectively (p = 0.91). Emergent operation, ejection fraction less than 0.30, operative age greater than 65 years, NYHA class III/IV, and chronic obstructive pulmonary disease were significant predictors of mortality. The number of stenosed vessels, the number of bypass grafts, incomplete revascularization, and the presence of aortic stenosis or aortic insufficiency did not predict mortality.

CONCLUSIONS: For patients undergoing AVR-CABG, the number of bypass grafts does not adversely affect survival. Rather, a patient's preoperative risk factors are a better predictor of outcome.