RF44 OUTCOME AFTER BILATERAL INTERNAL MAMMARY ARTERY GRAFTING IN HIGH- AND LOW-VOLUME HOSPITALS: AN ANALYSIS OF THE E-CABG REGISTRY

Abstract

Background: Bilateral internal mammary artery (BIMA) grafting is largely underutilized in patients undergoing coronary artery bypass grafting (CABG), partly because of the perceived increased complexity of the procedure. In this study we evaluated whether BIMA grafting can be safely performed also in centers in which this revascularization strategy is infrequently adopted. Methods: Out of 6783 patients from the prospective multicenter E-CABG study, who underwent isolated non-emergent CABG from January 2015 to December 2016, 2457 underwent BIMA grafting and their outcome was evaluated in this analysis. Results: The mean number of BIMA grafting per center was 82 cases/year and hospitals were defined as high- or low-volume according to this cutoff value. Six hospitals were considered as centers with high-volume of BIMA grafting (no. of procedures ranging from 120 to 267/year; overall: 2156; prevalence: 62.2%) and nine hospitals as centers with low-volume of BIMA grafting (no. of procedures ranging from 2 to 39/year; overall: 301; prevalence: 9.1%). Multilevel mixed-effects regression analysis showed that the low- and high-volume cohorts had similar outcomes. Propensity score one-to-one matching analysis of 292 pairs showed that the low-volume cohort had a significantly shorter intensive care unit stay (2.2 ± 2.3 vs. 2.9 ± 4.8 days, p = 0.020). The rates of in-hospital death (1.0% vs. 0.3%, p = 0.625), deep sternal wound infection/mediastinits (3.8% vs. 3.1%, p = 0.824) and 1-year survival (98.1% vs. 99.7%, p = 0.180) as well as other outcomes were similar between the high- and low-volume cohorts. Conclusions: BIMA grafting can be safely performed also in centers in which this revascularization strategy is infrequently performed.