title: Catheter ablation of ventricular fibrillation: importance of left ventricular outflow tract and papillary muscle triggers.
abstract: BACKGROUND
  Monomorphic ventricular premature depolarizations (VPDs) have been found to initiate ventricular fibrillation (VF) or polymorphic ventricular tachycardia (PMVT) in patients with and without structural heart disease.
  
  
  OBJECTIVE
  The purpose of this study was to describe and characterize sites of origin of VPDs triggering VF and PMVT.
  
  
  METHODS
  The distribution of mapping-confirmed VPDs, electrophysiology laboratory findings, and results of radiofrequency catheter ablation were analyzed.
  
  
  RESULTS
  Among 1132 consecutive patients who underwent ablation for ventricular arrhythmias, 30 patients (2.7%) with documented VF/PMVT initiation were identified. In 21 patients, VF/PMVT occurred in the setting of cardiomyopathy; in 9 patients, VF/PMVT was idiopathic. The origin of VPD trigger was from the Purkinje network in 9, papillary muscles in 8, left ventricular outflow tract in 9, and other low-voltage areas unrelated to Purkinje activity in 4. Each distinct anatomic area of origin was associated with VF/PMVT triggers in patients with and without heart disease. Acute VPD elimination was achieved in 26 patients (87%), with a decrease in VPDs in another 3 patients (97%). During median follow-up of 418 days (interquartile range [IQR] 144-866), 5 patients developed a VF/PMVT recurrence after a median of 34 days (IQR 1-259). Rare recurrence was noted in patients with and without structural disease and from each distinct anatomic origin. The total burden of VF/PMVT episodes/shocks was reduced from a median of 9 (IQR 2.5-22.5) in the 3 months before ablation to 0 (IQR 0-0, total range 0-2) during follow-up (P <.0001).
  
  
  CONCLUSIONS
  Catheter ablation of VPD-triggered VF/PMVT is highly successful. Left ventricular outflow tract and papillary muscles are common and are previously unrecognized sites of origin of these triggers in patients with and without structural heart disease.
authors.affiliation: Electrophysiology Section, Cardiovascular Division, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Hugo
authors.initials: H
authors.lastname: Van Herendael
authors.affiliation: Electrophysiology Section, 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: School of Medicine, The University of Queensland, Department of Cardiology, The Prince Charles Hospital, Brisbane, Australia.
authors.forename: Haris
authors.initials: H
authors.lastname: Haqqani
authors.affiliation: Electrophysiology Section, Cardiovascular Division, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Cory M
authors.initials: CM
authors.lastname: Tschabrunn
authors.affiliation: Electrophysiology Section, 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: Electrophysiology Section, Cardiovascular Division, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: David S
authors.initials: DS
authors.lastname: Frankel
authors.affiliation: Electrophysiology Section, Cardiovascular Division, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: David
authors.initials: D
authors.lastname: Lin
authors.affiliation: Electrophysiology Section, Cardiovascular Division, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Fermin
authors.initials: F
authors.lastname: Garcia
authors.affiliation: Electrophysiology Section, 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: Electrophysiology Section, Cardiovascular Division, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Michael
authors.initials: M
authors.lastname: Riley
authors.affiliation: Electrophysiology Section, Cardiovascular Division, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Rupa
authors.initials: R
authors.lastname: Bala
authors.affiliation: Electrophysiology Section, Cardiovascular Division, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Sanjay
authors.initials: S
authors.lastname: Dixit
authors.affiliation: Electrophysiology Section, Cardiovascular Division, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Mrinal
authors.initials: M
authors.lastname: Yadava
authors.affiliation: Electrophysiology Section, Cardiovascular Division, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania. Electronic address: francis.marchlinski@uphs.upenn.edu.
authors.forename: Francis E
authors.initials: FE
authors.lastname: Marchlinski
mesh_terms: D009202:Cardiomyopathies / Q000150:complications; D017115:Catheter Ablation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010210:Papillary Muscles / Q000502:physiology*; D012008:Recurrence; D012189:Retrospective Studies; D017180:Tachycardia, Ventricular / Q000209:etiology / Q000503:physiopathology; D016896:Treatment Outcome; D014693:Ventricular Fibrillation / Q000209:etiology / Q000503:physiopathology* / Q000601:surgery*; D016276:Ventricular Function
keywords: Catheter ablation; Outflow tract; Papillary muscle; Ventricular fibrillation; Ventricular premature depolarization