Risk Factors and Outcomes in Redo Coronary Artery Bypass Grafting

Background Reoperative coronary artery bypass grafting (redo-CABG) has declined during the last decade, while use of percutaneous coronary intervention (PCI) has increased. The aim of this retrospective study was to evaluate risk factors, in-hospital mortality, and long-term survival between first-time CABG and redo-CABG. Methods From January 2009 to December 2015, 2,581 patients underwent first-time CABG procedures while 132 underwent isolated redo-CABG. Logistic regression was used to identify risk factors predictive of redo-CABG and after propensity matching the in-hospital morbidity and long-term all-cause mortality were compared. Results Risk factors for redo-CABG were prior PCI, dyslipidaemia, diabetes and hypertension. After propensity matching there were no significant differences between the redo-CABG (n = 126) and first-time CABG groups (n = 232) in baseline characteristics. The adjusted in-hospital mortality was 3.1% for redo-CABG and 2.1% for first-time CABG (p = 0.55). Redo-CABG required significantly more intraoperative red blood cells (p = 0.03), platelets (p < 0.001), cryoprecipitate (p < 0.007) and fresh frozen plasma (p < 0.001) than first-time CABG. There was no significant difference in reoperation for bleeding (p = 0.72), prolonged ventilation (p = 0.98), postoperative stroke (p = 0.92) or dialysis (p = 0.44). The survival at 1, 3 and 5 years for redo-CABG was 93.5%, 90%, and 85% respectively, and 95.5%, 94.5%, 93% for first-time CABG, respectively (p = 0.2). Conclusions Prior PCI after first time CABG and the risk factors for atherosclerotic disease are predictive for redo-CABG. An increased use of blood products is required during redo-CABG. After propensity matching, in-hospital mortality and long-term survival for redo-CABG is comparable to first-time operation. Re-sternotomy does not impact the survival in redo-CABG.