title: Idiopathic ventricular arrhythmias originating from the moderator band: Electrocardiographic characteristics and treatment by catheter ablation.
abstract: BACKGROUND
  The moderator band (MB) can be a source of premature ventricular contractions (PVCs), monomorphic ventricular tachycardia (VT), and idiopathic ventricular fibrillation (IVF).
  
  
  OBJECTIVE
  The purpose of this study was to define the electrocardiographic (ECG) characteristics and procedural techniques to successfully identify and ablate MB PVCs/VT.
  
  
  METHODS
  In 10 patients with left bundle branch block morphology PVCs/VT, electroanatomic mapping in conjunction with intracardiac echocardiography (ICE) localized the site of origin of the PVCs to the MB. Clinical characteristics of the patients, ECG features, and procedural data were collected and analyzed.
  
  
  RESULTS
  Seven patients presented with IVF and 3 presented with monomorphic VT. In all patients, the ventricular arrhythmias (VAs) had a left bundle branch block QRS with a late precordial transition (>V4), a rapid downstroke of the QRS in the precordial leads, and a left superior frontal plane axis. Mean QRS duration was 152.7 ± 15.2 ms. Six patients required a repeat procedure. After mean follow-up of 21.5 ± 11.6 months, all patients were free of sustained VAs, with only 1 patient requiring antiarrhythmic drug therapy and 1 patient having isolated PVCs no longer inducing VF. There were no procedural complications.
  
  
  CONCLUSIONS
  VAs originating from the MB have a distinctive morphology and often are associated with PVC-induced ventricular fibrillation. Catheter ablation can be safely performed and is facilitated by ICE imaging.
authors.affiliation: Section of Cardiac Electrophysiology, Cardiovascular Division, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Mouhannad M
authors.initials: MM
authors.lastname: Sadek
authors.affiliation: Section of Cardiac Electrophysiology, Cardiovascular Division, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Daniel
authors.initials: D
authors.lastname: Benhayon
authors.affiliation: Section of Cardiac Electrophysiology, Cardiovascular Division, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Ravi
authors.initials: R
authors.lastname: Sureddi
authors.affiliation: Section of Cardiac Electrophysiology, Cardiovascular Division, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: William
authors.initials: W
authors.lastname: Chik
authors.affiliation: Section of Cardiac Electrophysiology, Cardiovascular Division, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Pasquale
authors.initials: P
authors.lastname: Santangeli
authors.affiliation: Section of Cardiac Electrophysiology, Cardiovascular Division, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Gregory E
authors.initials: GE
authors.lastname: Supple
authors.affiliation: Section of Cardiac Electrophysiology, Cardiovascular Division, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Mathew D
authors.initials: MD
authors.lastname: Hutchinson
authors.affiliation: Section of Cardiac Electrophysiology, Cardiovascular Division, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Rupa
authors.initials: R
authors.lastname: Bala
authors.affiliation: Section of Cardiac Electrophysiology, Cardiovascular Division, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Lidia
authors.initials: L
authors.lastname: Carballeira
authors.affiliation: Section of Cardiac Electrophysiology, Cardiovascular Division, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Erica S
authors.initials: ES
authors.lastname: Zado
authors.affiliation: Section of Cardiac Electrophysiology, Cardiovascular Division, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Vickas V
authors.initials: VV
authors.lastname: Patel
authors.affiliation: Section of Cardiac Electrophysiology, Cardiovascular Division, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: David J
authors.initials: DJ
authors.lastname: Callans
authors.affiliation: Section of Cardiac Electrophysiology, Cardiovascular Division, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Francis E
authors.initials: FE
authors.lastname: Marchlinski
authors.affiliation: Section of Cardiac Electrophysiology, Cardiovascular Division, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania. Electronic address: fermin.garcia@uphs.upenn.edu.
authors.forename: Fermin C
authors.initials: FC
authors.lastname: Garcia
mesh_terms: D000328:Adult; D017115:Catheter Ablation; D015331:Cohort Studies; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017180:Tachycardia, Ventricular / Q000175:diagnosis / Q000503:physiopathology* / Q000601:surgery*; D016896:Treatment Outcome; D014693:Ventricular Fibrillation / Q000175:diagnosis / Q000503:physiopathology* / Q000601:surgery*; D018879:Ventricular Premature Complexes / Q000175:diagnosis / Q000503:physiopathology* / Q000601:surgery*
keywords: Catheter ablation; Idiopathic ventricular fibrillation; Intracardiac echocardiography; Moderator band; Premature ventricular contractions