title: Electrophysiologic characteristics and catheter ablation of ventricular tachyarrhythmias among patients with heart failure on ventricular assist device support.
abstract: BACKGROUND
  Ventricular tachyarrhythmias (VT) are common among ventricular assist device (VAD) recipients, yet electrophysiologic (EP) characteristics and catheter ablation outcomes remain uncharacterized.
  
  
  OBJECTIVE
  To evaluate the EP characteristics and catheter ablation outcomes for VTs among heart failure patients on VAD support.
  
  
  METHODS
  The Cleveland Clinic registry of consecutive patients undergoing VAD placement in 1991-2010 with medically refractory, symptomatic VT referred for EP study and catheter ablation.
  
  
  RESULTS
  Among 611 recipients of VAD (mean age 53.3 ± 12.4 years, 80% men), 21 patients (3.4%) were referred for 32 EP procedures, including 11 patients (52%) presenting with implantable cardioverter-defibrillator therapy (13 shocks, 26 antitachycardia pacing). Data from 44 inducible tachycardias (mean cycle length 339 ± 59 ms) demonstrated monomorphic VT (n = 40, 91%; superior axis 52%, right bundle branch block morphology 41%) and polymorphic ventricular tachycardia (PMVT)/ventricular fibrillation (n = 4, 8%). Electroanatomic mapping of 28 tachycardias in 20 patients demonstrated reentrant VT related to intrinsic scar (n = 21 of 28, 75%) more commonly than the apical inflow cannulation site (n = 4 of 28, 14%), focal/microreentry VT (n = 2 of 28, 7%), or bundle branch reentry (n = 1 of 28, 3.5%). Catheter ablation succeeded in 18 of 21 patients (86%). VT recurred in 7 of 21 patients (33%) at a mean of 133 ± 98 days, and 6 patients (29%) required repeat procedures, with subsequent recurrence in 4 of 21 patients (19%).
  
  
  CONCLUSIONS
  Catheter ablation of VT is effective among recipients of VAD. Intrinsic myocardial scar, rather than the apical device cannulation site, appears to be the dominant substrate.
authors.affiliation: Cleveland Clinic, Sydell and Arnold Miller Family Heart and Vascular Institute, Cleveland, OH 44195, USA. cantild@ccf.org
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Cantillon
authors.forename: Christopher
authors.initials: C
authors.lastname: Bianco
authors.forename: Oussama M
authors.initials: OM
authors.lastname: Wazni
authors.forename: Mohamed
authors.initials: M
authors.lastname: Kanj
authors.forename: Nicholas G
authors.initials: NG
authors.lastname: Smedira
authors.forename: Bruce L
authors.initials: BL
authors.lastname: Wilkoff
authors.forename: Randall C
authors.initials: RC
authors.lastname: Starling
authors.forename: Walid I
authors.initials: WI
authors.lastname: Saliba
mesh_terms: D017115:Catheter Ablation / Q000379:methods*; D022062:Electrophysiologic Techniques, Cardiac / Q000379:methods*; D055724:Electrophysiological Phenomena; D005260:Female; D005500:Follow-Up Studies; D006329:Heart Conduction System / Q000503:physiopathology / Q000601:surgery*; D006333:Heart Failure / Q000503:physiopathology / Q000628:therapy*; D006352:Heart Ventricles / Q000503:physiopathology*; D006353:Heart-Assist Devices / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D017180:Tachycardia, Ventricular / Q000209:etiology / Q000503:physiopathology* / Q000601:surgery