Evaluation of myocardial protection in off-pump vs on-pump coronary bypass surgery by troponin I estimation

Abstract

Background: This prospective non-randomized clinical study was done to compare Off-pump and On-pump myocardial revascularization by Troponin I release in patients undergoing first elective coronary artery bypass graft used to evaluate myocardial injury. Methods: One hundred an twenty patients were non-randomly assigned to a Off-pump or On-pump myocardial revascularization group. Cardiac Troponin I (CTnI) were measured in serial venous blood samples drawn preoperatively in both groups. In On-pump group after aortic unclamping at 12 and 24 hours and in Off-pump group after the last distal anastomosis at 12 and 24 hours. Results: The total amount of CTnI release were significantly higher in On-pump group than in Off-pump group. In On-pump group it was 2.1±1.9 (mean±SD) ng/ml vs in Off-pump group it was 1.0±1.7 (mean±SD) ng/ml at 12 hours and in On-pump group it was 1.6±1.6 (mean±SD) ng/ml vs in Off-pump group it was .9±1.6 (mean±SD) ng/ml at 24 hours (P<0.0001 for the pattern). Conclusion: The lower release of CTnI in the Off-pump myocardial revascularization group indicates that the arrested heart coronary revascularization group causes more damage to the heart due to cardiopulmonary bypass than Off-pump myocardial revascularization group.