BACKGROUND: CABG surgery on the beating heart (off-pump) is increasingly used to lessen injury to the brain, kidneys and other organs. However, the perioperative incidence of myocardial injury and its effect on outcome vs conventional CABG (on-pump) remains unclear. MATERIAL AND METHODS: Retrospective study of 303 patients (122 off-pump, 181 on-pump) after isolated CABG from Feb/97-Feb/99. CPK and EKG were obtained pre and post-op, MB fraction and troponin T levels were measured postoperatively. Complications were also recorded. The groups were comparable in terms of age (65 ± 10 vs 65 ± 9 yr), CCS and NYHA class. RESULTS: Mean number of grafts was 3.10 on-pump vs 2.26 off-pump. Perioperative myocardial infarction, morbidity and mortality (7/181 vs 6/122) were also comparable. There were higher postoperative CK levels in the on-pump group compared to the off-pump (548 ± 420 vs 236 ± 365). MB fraction was slightly higher in the on-pump group, but not significantly different (62 ± 197 vs 29 ± 46) nor was troponin T levels (3.5 ± 16 vs 3.5 ± 17) were An inverse correlation between the number of grafts and troponin T release in the off-pump group occurred early during our off-pump experience. There was no correlation between graft location and the incidence of infarcts or troponin T release. CONCLUSION: The higher troponin T release during our initial experience subsequently decreased. This suggests that improvements in operative technique (e.g. better exposure allowing more posterior grafts without surface trauma) may be responsible. Current techniques make off-pump CABG a safe alternative for revascularization.
Myocardium; Myocardial revascularization; Myocardial revascularization; Myocardial revascularization; Extracorporeal circulation; Extracorporeal circulation