Assessment of Ventricular Electrophysiological Characteristics at Periinfarct Zone of Postmyocardial Infarction in Rabbits following Stellate Ganglion Block

Abstract

Assessment of Ventricular Electrophysiological Characteristics. The aim of this study was to investigate the characteristics of ventricular electrophysiology following stellate ganglion block (SGB) at periinfarct zone in rabbits with myocardial infarction (MI). Sixty-four rabbits were randomly assigned to 2 groups: MI (n = 32), ligation of the anterior descending coronary and sham operation (SO) (n = 32), without coronary ligation. Both MI and SO groups were divided into 4 subgroups according to right or left SGB and corresponding control (n = 8, each). After 8 weeks, 90% of monophasic action potential duration (MAPD90) of epicardium, midmyocardium and endocardium, transmural dispersion of repolarization (TDR), effective refractory period (ERP), and ventricular fibrillation threshold (VFT) were measured at the infarct border zone (MI group) and corresponding zone (SO group) following SGB. For SGB, 0.5 mL of 0.25% bupivacaine was used. Compared with the corresponding control group, in both the MI and SO groups, left SGB (LSGB) prolonged the MAPD90 of the 3 layers, reduced TDR, and increased ERP and VFT (P < 0.05). However, right SGB (RSGB) shortened MAPD90, increased TDR, and reduced ERP and VFT (P < 0.05). The results of this study demonstrate that LSGB can increase the electrophysiological stability of ventricular myocardium.