Ventricular fibrillation resulting from synchronized internal atrial defibrillation in a patient with ventricular preexcitation

J Cardiovasc Electrophysiol. 1997 Apr;8(4):436-40. doi: 10.1111/j.1540-8167.1997.tb00809.x.


This case describes ventricular proarrhythmia as a result of a synchronized internal atrial defibrillation shock in a 29-year-old man with Ebstein's anomaly referred for radiofrequency ablation of a right posterior accessory pathway. During the electrophysiologic study, atrial fibrillation was induced and 3/3 msec shocks of various strengths were delivered between two decapolar defibrillation catheters in the coronary sinus and right atrial appendage. A 2.0-J biphasic shock synchronized to an R wave after a short-long-short ventricular cycle length pattern with a preshock coupling interval of 245 msec induced ventricular fibrillation, which was externally defibrillated with 200 J. This observation has implications for the development of implantable atrial defibrillators.

Publication types

  • Case Reports

MeSH terms

  • Adult
  • Catheter Ablation
  • Ebstein Anomaly / complications
  • Ebstein Anomaly / physiopathology
  • Ebstein Anomaly / surgery
  • Electric Countershock / adverse effects*
  • Electrocardiography
  • Humans
  • Male
  • Pre-Excitation Syndromes / complications
  • Pre-Excitation Syndromes / physiopathology
  • Pre-Excitation Syndromes / therapy*
  • Ventricular Fibrillation / etiology*
  • Ventricular Fibrillation / physiopathology