Ablation of the ligament of Marshall reduces the incidence of ventricular arrhythmias post-acute myocardial infarction in canine

Abstract

Objective The present study aimed to investigate the effects of ablation of ligament of Marshall (LOM) or left stellate ganglion (LSG) on ventricular arrhythmias post-acute myocardial infarction in canine. Methods Twenty-nine adult mongrel male dogs were randomized into the sham-ablation group (n=9) , LOMLSPV ablation group (n=10) and LSG ablation group (n=10) . The dogs underwent LOMLSPV or LSG ablation before left anterior descending diagonal occlusion in the two ablation groups, while only left anterior descending diagonal occlusion without ablation was performed in the sham-ablation group. Blood pressure (BP) , heart rate (HR) , heart rate variability (HRV) and ventricular effective refractory period (ERP) were measured before and after ablation. The BP change as response to LSG stimulation was observed as well before and after ablation in LOMLSPV ablation group. AMI was induced by ligating the left anterior descending diagonal, then ventricular arrhythmias was recorded during 1-hour of AMI. Results No obvious changes of BP and HR were observed after the ablation of LOMLSPV or LSG when compared to the baseline. Both LOMLSPV ablation and LSG ablation can significantly prolong ventricular ERP, reduce the LF components and LF/HF, and increase the HF components compared with the sham-ablation group (all P<0.05) . LOMLSPV ablation evidently attenuated the elevation of BP induced by LSG stimulation. Besides, the occurrence of ventricular premature contraction and ventricular tachycardia was significantly decreased both in LOMLSPV ablation group and LSG ablation group (all P<0.05) . 1 dog died of ventricular fibrillation in each group. Conclusion LOMLSPV ablation reduces the incidence of ventricular arrhythmias post-acute myocardial infarction as LSG ablation, and the possible mechanism may be that ablation of LOMLSPV blocks the sympathetic pathway from LSG to ventricle. Key words: Ligament of Marshall; Stellate ganglion; Arrhythmias