Does lidocaine protect the heart during coronary revascularisation?

Abstract

Lidocaine has been used as the primary antiarrhythmic agent for ventricular arrhythmias during acute myocardial infarction (MI) and open heart surgery. Its cardioprotective effects have been studied in experimental settings and also during angioplastic reperfusion and coronary revascularisation. The basic mechanism of action, probably also involved with cardioprotection, has been demonstrated to be blockade of cardiac sodium channels. In this open study we investigated the contribution of continuous lidocaine infusion to cardioprotection during coronary revascularisation with blood cardioplegia. During coronary revascularisation with cold blood cardioplegia, a study group of 50 patients received a prophylactic lidocaine infusion for 20 h started with a bolus dose before aortic clamping; another group of 50 patients without the infusion served as a control group. Serum troponin T concentration, serum creatine kinase MB activity and electrocardiography were the main parameters recorded. Serial measurement of Troponin T (P = 0.06) and CK-MB values: (P = 0.09) were slightly lower in the lidocaine group, but the differences were not statistically significant. Lacking statistically significant evidence of improved cardioprotection, lidocaine infusion cannot be recommended as a routine treatment during coronary revascularisation.