Impact of prior coronary stenting on the outcome of subsequent coronary artery bypass grafting

Background: The percentage of patients referred for coronary artery bypass grafting (CABG) who have previously undergone percutaneous coronary interventions (PCIs) is increasing. The purpose of this study was to review the outcomes of patients who had received coronary stenting before CABG, and to examine the validity of a mortality risk stratification system in this patient group. Methods: From 2010 to 2012, 439 patients who underwent isolated CABG at our medical center were reviewed. The patients were divided into two study groups: those who had previously received coronary artery stenting (97 patients, 24.7%), and those who had not (342 patients, 75.3%). The patients who received balloon angioplasty were excluded. Results: There were no significant differences in baseline characteristics. The prior stenting group had a lower risk of mortality, although the difference was not significant. The prior stenting group had fewer graft anastomoses (p = 0.005), and hence a significantly shorter cardiopulmonary bypass time (p = 0.045) and shorter aortic cross-clamping time. Surgical mortality was similar between the two groups. The durations of intensive care unit stay and hospitalization were also similar. The discriminatory power of the logistic European System for Cardiac Operative Risk Evaluation (EuroSCORE) was lower in both group. Conclusions: Prior coronary stenting does not affect short-term mortality in patients subsequently undergoing CABG surgery. The EuroSCORE does not predict perioperative mortality well for the patients who undergo coronary stenting before CABG.