title: Ventricular fibrillation resulting from synchronized internal atrial defibrillation in a patient with ventricular preexcitation.
abstract: 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.
authors.affiliation: Department of Medicine, Duke University Medical Center, Durham, North Carolina 27710, USA.
authors.forename: H S
authors.initials: HS
authors.lastname: Barold
authors.forename: J M
authors.initials: JM
authors.lastname: Wharton
mesh_terms: D000328:Adult; D017115:Catheter Ablation; D004437:Ebstein Anomaly / Q000150:complications / Q000503:physiopathology / Q000601:surgery; D004554:Electric Countershock / Q000009:adverse effects*; D004562:Electrocardiography; D006801:Humans; D008297:Male; D011226:Pre-Excitation Syndromes / Q000150:complications / Q000503:physiopathology / Q000628:therapy*; D014693:Ventricular Fibrillation / Q000209:etiology* / Q000503:physiopathology