Prognostic Impact of Prolonged Cross-Clamp Time in Coronary Artery Bypass Grafting

Abstract

The prognostic impact of cross-clamp time (XCT) in patients undergoing isolated coronary artery bypass grafting (CABG) has not been thoroughly investigated. 2957 patients who underwent on-pump isolated CABG from the prospective multicentre E-CABG study were the subjects of this analysis. The mean XCT in this series was 58±25minutes Cross-clamp time was >60 minutes in 1134 patients (38.3%), >75minutes in 619 patients (20.9%) and >90minutes in 296 patients (10.0%). Multivariate analysis showed that XCT was an independent predictor of 30-day mortality (p<0.0001, OR 1.027, 95%CI 1.015-1.039) along with age (p<0.0001), female gender (p=0.001), pulmonary disease (p=0.001), poor mobility (p=0.002), urgency status (p=0.007), critical preoperative status (p=0.002) and participating centres (p=0.015). Adjusted risk of 30-day mortality was highest for XCT >75minutes (2.9% vs. 1.7%, p=0.002, OR 3.479, 95%CI 1.609-7.520). Analysis of 428 propensity score matched pairs showed that XCT >75minutes was associated with significantly increased risk of early mortality, prolonged use of inotropes, postoperative use of intra-aortic balloon pump, use of extracorporeal membrane oxygenation, atrial fibrillation, prolonged stay in the intensive care unit and of composite major adverse events. Isolated CABG is currently performed with prolonged XCT in a significant number of patients and this seems to be a determinant of poor early outcome.