Electrocardiographic and radiofrequency catheter ablation for ventricular arrhythmias arising from the right bundle branch ot the moderator band / 中国介入心脏病学杂志

ABSTRACT

Objective To investigate the electrophysiological characteristics and curative effect of radiofrequency ablation(RFA)of idiopathic ventricular arrhythmias(VAs)originating from the right bundle branch of the moderator band.Methods The patients(n=10)with idiopathic VAs originating from the right bundle branch of the moderator band verified by electrophysiological examination and RFA were chosen from Department of Cardiology in Beijing Anzhen Hospital affiliated to Capital Medical University from April 2019 to July 2022.Excited sequence mapping and pacing mapping were performed respectively on the moderator band.The characteristics of surface ECG,electrophysiological characteristics and potential characteristics at successful ablation targets were analyzed,and curative effect of RFA was observed and analyzed.Results Idiopathic VAs originated from the moderator band,and surface ECG showed mostly graph of left bundle branch block(LBBB)with left superior axis deviation and a narrower QRS complex.All patients showed an rS wave in leads V,and V2,and no notching on the S wave downstroke.The R-wave transition lead was at leads V4-V6 during VAs,which was later than that during sinus rhythm in all patients.All patients had an R wave in lead V6.A leading RBB potential at the target during VAs was observed for all patients.Ablation of the leading RBB potential effectively eliminated the arrhythmia.6 patients showed RBB block after ablation and 2 of them were recovered during follow-up.Conclusions Electrocardiographic of MB-RBB VAs is characterized by a typical left bundle branch block pattern with a relatively narrow QRS complex,and left superior axis deviation.The R-wave transition lead was later than that during sinus rhythm.Ablation of the leading RBB potential are effective in eliminating VAs.