Abstract 16232: Early Morbidity Affects Survival Beyond the Perioperative Period in On-Pump vs. Off-Pump Coronary Artery Bypass Graft Surgery - A Quantitative Morbidity Analysis of the CORONARY Trial

Introduction: Previous large trials found similar outcomes between on- and off-pump CABG. We assessed the hypothesis that quantified early morbidity affects survival after 30 postoperative days by applying the Clavien-Dindo Complications Classification (CDCC) and the Comprehensive Complication Index (CCI) to the CORONARY trial. Methods: All postoperative hospitalization and 30-days follow-up complications were assigned a CDCC grade. CCI were calculated for all patients (n=4752) ( Table 1 ). Kaplan-Meier analysis was used to examine 1-year mortality by CDCC grade in patients alive after 30 postoperative days. Wilcoxon and log-rank were used for comparisons. Results: Median CDCC was 1 [interquartile range: 0, 2] for off-pump and 2 [1, 2] for on-pump CABG (p<0.001). Median CCI was 8.7 [0, 22.6] for off-pump and 20.9 [8.7, 29.6] for on-pump CABG (p<0.001). In on-pump CABG, there were more grade I complications (off: n=1093, 46.0% vs. on: n=1280, 53.8%; p<0.001) and grade II complication (off: n=903, 38.0% vs. on: n=1012, 42.6%; p<0.001) ( Figure 1a ). In on-pump CABG, 17.5% (n=417) had grade IIIa or greater morbidity versus 15.9% (n=378) in off-pump (p=0.133). Survival curves differed significantly based on CDCC grade ( Figure 1b , p<0.001). The CCI was 8.7 [0, 22.6] in patients who survived (n=4514) and 22.6 [8.7, 44.3] in patients who died (n=94) at one year (p<0.001). Conclusions: On-pump CABG is associated with greater early morbidity graded by CDCC and CCI. This affects survival beyond the immediate postoperative period. Similar quantitative analyses have not been used to compare the two techniques and could prove useful to better quantify procedural morbidity in clinical trials.