Background: We planned the usage of both bolus and infusion lidocaine in our study in CABG and in the efficiency of myocardial protection with serum Troponin-T (Tn-T) levels.

Methods: After ethic committee’s approval, 45 patients scheduled for an elective CABG were randomised to three groups (n = 15). First group (control) with standart cold crystalloid cardioplegia, 2. group with additional lidocaine bolus (1 mg/kg) and 3. group lidocaine infusion (20 µg/kg/min) before cardiac cannulation. Troponin-T, creatinin kinase (CK), CK-MB and lactic dehydrogenase were assessed before the operation and postoperative 6, 12, 24 and 48 hours. Twelve-lead electrocardiogram was recorded peroperative and repeated during the first 48 postoperative hours in parallel with biochemical analyses.

Results: Elevated circulating Tn-T, CK and lactic dehydrogenase levels were no significant between the groups. But the change of CK-MB level was significantly. Troponin-T and CK-MB changes with respect to control group were lower using lidocaine both 2 and 3. groups. Electrocardiographic changes were observed in 8 patients (60%) in first group, in 4 patients (26.6%) in the bolus lidocaine group and in 3 patients (20%) in the infusion lidocaine group.

Conclusion: Lidocaine infusion may be a useful adjunct to myocardial protection, as determined by the analysis of Tn-T and CK-MB.

Keywords : Coronary artery bypass grafting, myocardial protection, lidocaine, troponin