title: Effectiveness of VF induction with DC fibber versus conventional induction methods in patients on chronic amiodarone therapy.
abstract: BACKGROUND
  Amiodarone therapy, especially chronic, can result in difficult ventricular fibrillation (VF) inductions during implantable cardioverter defibrillator (ICD) testing. The efficacy of various VF induction methods on patients treated with amiodarone has not been well described. This prospective analysis evaluated the impact of direct current (DC) fibber, burst fibber, and synchronized T-wave shock VF induction methods.
  
  
  METHODS
  Data were collected from one study and two enrolling centers totaling 14 ICD patients (92.9 % male, age 64.3 years (range 23.6-81.2)). A minimum of two successful VF inductions from each patient were required to be included in the study analysis. Each VF induction method was attempted in each patient. Non-sustained VF resulting in an aborted shock was considered an induction failure. All 14 patients were on chronic amiodarone therapy.
  
  
  RESULTS
  From a total of 42 attempted inductions, 25 (59.5 %) were successful at inducing VF. The success rates of effective induction of VF during the first attempt using DC, burst, and Shock-on-T are 100, 50, and 28.6 %, respectively. DC fibber had significantly higher VF induction rates than Shock-on-T (p = 0.004) or burst fibber (p = 0.02). There was no difference between Shock-on-T and burst fibber (p = 0.45).
  
  
  CONCLUSIONS
  The success rate of VF induction using DC fibber method is significantly higher than either Shock-on-T or burst fibber induction methods for patients on chronic amiodarone therapy. This may facilitate defibrillation threshold testing in such patients.
authors.affiliation: Division of Cardiology, Department of Medicine, Medical College of Wisconsin, Milwaukee, WI, USA.
authors.forename: Jason C
authors.initials: JC
authors.lastname: Rubenstein
authors.forename: Manish S
authors.initials: MS
authors.lastname: Gupta
authors.forename: Michael H
authors.initials: MH
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000638:Amiodarone / Q000008:administration & dosage*; D000889:Anti-Arrhythmia Agents / Q000008:administration & dosage; D002908:Chronic Disease; D017147:Defibrillators, Implantable; D004562:Electrocardiography / Q000187:drug effects*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016896:Treatment Outcome; D014481:United States; D014693:Ventricular Fibrillation / Q000175:diagnosis* / Q000517:prevention & control*; D055815:Young Adult
chemical_list: D000889:Anti-Arrhythmia Agents; D000638:Amiodarone