| Objective: The study is to compare the postoperative release of cardiac troponin I(cTnI) and CK-MB between off-pump coronary artery bypass graft ing(OPCAB) and conventional coronary artery bypass graft ing(CCABG) in attempt to detect myocardial injury .Patients and Methods: One hundred and two patients with instable angina underent coronary artery bypass grafting by OPCAB in 71 patients aged(61. 35#8. 82) years or CCABG in 31 patients aged(60. 32#7. 02) years. Baseline characteristics of the two groups were similar. Serial venous blood samples were drawn before operation and at 4,12,24, 72, 120 hours after backing to ICU and were centrifuged immediately. Plasma for cTnl and CK-MB mass measurements was stored at - 20癈 untilanalysis. The normal range of CK-MB is <16U/L and cTnl is <2. 8ug/L. In all patients , ECG recordings were obtained before operation and on the 7th postoperative day. The diagnosis of perioperative myocardial infarction (PMI) was based on the presence of following critetria: 1. a new Q wave on postoperative ECG tracing;2.peak CK-MB mass level in excess of 50U/L.Result: The number of grafts was similar (OPCAB, mean 2.69;CCABG, mean2. 97). No patient had evidence of PMI and there were no in-hospital deaths. Postoperative myocardial cTnl measures were significantly lower in OPCAB group than in CCABG group at every time point, with the largest differences occurring 4 hours , 12 hours and 24 hours after operation(p<0. 01), peak value was at 12 hours. Similar trend was present with CK-MB, but peak value was at 4 hours. cTnl returned to normal in 5 days and CK-MB in 3 days. Patients' age and the number of bypass grafts were not correlated with postoperative peak value of cTnl in either group. Conclusion: The results of this study suggest that OPCAB is a safe method of myocardial revascularization. Compared with CCABG, OPCAB may create less myocardial injury .
|
PDF Full Text Request