Impact of Off-pump and On-pump Coronary Artery Bypass Grafting on In-hospital Mortality and Mid-term Survival of Octogenarians

Background: Octogenarians are being increasingly referred for coronary artery bypass grafting (CABG). However, there is a paucity of studies reporting impact of choice of surgical revascularization strategy on in-hospital mortality and mid-term survival of octogenarians. We evaluated our institutional experience to determine the impact of off-pump and on-pump CABG on in-hospital mortality and mid-term survival of octogenarians. Methods: We retrospectively analysed prospectively collected data from the Patients Analysis and Tracking System database (Dendrite Clinical Systems, Oxford, UK) for all isolated first-time CABG procedures with at least 2 grafts performed at our institution from January 2000 to September 2017. Over the study period, 566 octogenarians underwent either off-pump (N = 374) or on-pump CABG (N = 192). Short-term outcomes including in-hospital mortality as well as mid-term survival was compared for the two groups. Results: The two groups had similar preoperative demographics and mean number of distal anastomoses (off-pump: 2.7 ± 0.6 [median 3] vs on-pump: 2.7 ± 0.3 [median 3]; P=0.6). However, more bilateral internal mammary artery grafts were performed in the off-pump cohort compared to on-pump cohort (117 [31.3%] vs 22 [11.5%]; P <0.001). In-hospital mortality for the entire cohort was 5.7% with significantly fewer deaths in the off-pump cohort (4.3% vs 8.3%; P=0.04). The remaining in-hospital outcomes were similar. Kaplan-Meier survival at 1 year (89.7% vs 82.9%; P=0.048) and 5 year (71.1% vs 61.3%; P=0.038) was significantly better for the off-pump cohort. Conclusion: Octogenarians experience lower in-hospital mortality and improved mid-term survival after off-pump CABG compared to on-pump CABG.