Surgery for Coronary Artery Disease Five-Year Follow-Up of a Randomized Comparison Between Off-Pump and On-Pump Stable Multivessel Coronary Artery Bypass Grafting. The MASS III Trial

Background—Coronary artery bypass graft surgery with cardiopulmonary bypass is a safe, routine procedure. Nevertheless, significant morbidity remains, mostly because of the body’s response to the nonphysiological nature of cardiopulmonary bypass. Few data are available on the effects of off-pump coronary artery bypass graft surgery (OPCAB) on cardiac events and long-term clinical outcomes. Methods and Results—In a single-center randomized trial, 308 patients undergoing coronary artery bypass graft surgery were randomly assigned: 155 to OPCAB and 153 to on-pump CAB (ONCAB). Primary composite end points were death, myocardial infarction, further revascularization (surgery or angioplasty), or stroke. After 5-year follow-up, the primary composite end point was not different between groups (hazard ratio 0.71, 95% CI 0.41 to 1.22; P 0.21). A statistical difference was found between OPCAB and ONCAB groups in the duration of surgery (240 65 versus 300 87.5 minutes; P 0.001), in the length of ICU stay (19.5 17.8 versus 43 17.0 hours; P 0.001), time to extubation (4.6 6.8 versus 9.3 5.7 hours; P 0.001), hospital stay (6 2 versus 9 2 days; P 0.001), higher incidence of atrial fibrillation (35 versus 4% of patients; P 0.001), and blood requirements (31 versus 61% of patients; P 0.001), respectively. The number of grafts per patient was higher in the ONCAB than the OPCAB group (2.97 versus 2.49 grafts/patient; P 0.001). Conclusions—No difference was found between groups in the primary composite end point at 5-years follow-up. Although OPCAB surgery was related to a lower number of grafts and higher episodes of atrial fibrillation, it had no significant implications related to long-term outcomes. Clinical Trial Registration—URL: http://www.controlled-trials.com. Unique identifier: ISRCTN66068876. (Circulation. 2010;122[suppl 1]:S48–S52.)