title: Double sequential external shocks for refractory ventricular fibrillation.
abstract: OBJECTIVE
  A technique for terminating refractory ventricular fibrillation is described.
  
  
  BACKGROUND
  Refractory ventricular fibrillation can occur in up to 0.1% of electrophysiologic studies. Animal studies have shown that rapid sequential shocks may reduce ventricular fibrillation threshold.
  
  
  METHODS
  Five patients of 2,990 consecutive patients in a 3-year period experienced refractory ventricular fibrillation during 5,450 routine electrophysiologic studies. Multiple shocks were delivered by means of a single defibrillator. Double sequential shocks were delivered externally 0.5 to 4.5 s apart by means of two defibrillators with separate pairs of electrodes.
  
  
  RESULTS
  In all patients, standard defibrillation was unsuccessful, but all were successfully resuscitated using the double sequential shocks.
  
  
  CONCLUSIONS
  This report stresses the importance of an additional defibrillator being readily available during electrophysiologic testing. This technique of rapid, double sequential external shocks may have general applicability, providing a simple and potentially lifesaving approach to refractory ventricular fibrillation.
authors.affiliation: Cardiac Arrhythmia and Pacemaker Center, St. Francis Hospital, Roslyn, New York 11576.
authors.forename: D H
authors.initials: DH
authors.lastname: Hoch
authors.forename: W P
authors.initials: WP
authors.lastname: Batsford
authors.forename: S M
authors.initials: SM
authors.lastname: Greenberg
authors.forename: C M
authors.initials: CM
authors.lastname: McPherson
authors.forename: L E
authors.initials: LE
authors.lastname: Rosenfeld
authors.forename: M
authors.initials: M
authors.lastname: Marieb
authors.forename: J H
authors.initials: JH
authors.lastname: Levine
mesh_terms: D004554:Electric Countershock / Q000379:methods*; D004594:Electrophysiology; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D014693:Ventricular Fibrillation / Q000209:etiology / Q000628:therapy*