A comparison of off-pump and on-pump coronary bypass surgery in patients with low EuroSCORE

BACKGROUND The aim of the present study was to evaluate and compare postoperative short-term, mid-term and long-term outcomes of coronary artery bypass surgery performed with or without cardiopulmonary bypass in patients with a low European System for Cardiac Operative Risk Evaluation score. METHODS A retrospective analysis of 478 consecutive low risk patients undergoing coronary bypass surgery between January 2002 and December 2007 was performed. Of these patients, 83 cases had undergone on-pump and 395 cases had undergone off-pump coronary bypass surgery. The patients were assessed in terms peri-operative complications, survival, mortality due to cardiac events, need for rehospitalization and repeated coronary revascularization. RESULTS There was no significant difference between the two groups in terms of preoperative characteristics, except for chronic obstructive pulmonary disease. The number of distal anastomosis per patient was significantly lower in the off-pump group than in the on-pump group (2.66 ± 0.74 vs. 3.21 ± 0.85, p < 0.001). Early mortality rates were similar in both groups (1.01% for the off-pump group and 1.2% for the on-pump group, p = 0.687). Neurological complications were significantly lower in the off-pump group than in the on-pump group (1.1% vs. 6%, p = 0.01). The mean follow-up period was 80 ± 19.1 months (range, 3-112 months). The need for revascularization during long-term follow-up was 10.1% in the off-pump group and 7.2% in the on-pump group (p = 0.416). The 5-year survival was 95.2 ± 1.1% and 95.5 ± 2.7% in the off-pump and on-pump groups, respectively (p = 0.8), whereas the 7-year survival was 91.9 ± 1.6% and 84.7 ± 6.8% in the off-pump and on-pump groups, respectively (p = 0.274). The 5-year revascularization-free period was 89.5 ± 1.6% and 89.7 ± 3.5% in the off-pump and on-pump groups, respectively (p = 0.785). The 7-year revascularization-free period was 71.1 ± 3.1% and 73.5 ± 7.3% in the off-pump and on-pump groups, respectively (p = 0.075). The 7-year event-free survival was 80.1 ± 2.2% and 73.4 ± 7.3% in the off-pump and on-pump groups, respectively (p = 0.377). CONCLUSIONS The present study demonstrated that off-pump cardiac surgery had advantages over on-pump cardiac surgery in the short term; however, both interventions had similar mid-term and long-term outcomes, when performed in low-risk patient.