title: [Ventricular fibrillation in intra-atrial cardioversion of atrial fibrillation].
abstract: Recently intra-atrial defibrillation has become an interesting alternative to external defibrillation and drug therapy for the treatment of atrial fibrillation. Low-energy intra-atrial defibrillation can be used to restore sinus rhythm f.ex. after a failed external cardioversion or during an electrophysiologic study when the administration of antiarrhythmic drugs should be avoided. Additionally this new technique has led to the development of implantable atrial defibrillators for the treatment of selected patients suffering from chronic atrial fibrillation. Intra-atrial defibrillation seems to be a highly effective and safe method, but little experience exists concerning the outcome so far. Especially the potential risk of inducing ventricular pro-arrhythmia is subject of current controversy. We report the case of a 79-year-old patient suffering from WPW syndrome with a concealed bypass tract who was subject to an intra-atrial defibrillation during an electrophysiologic study. At the beginning of the study atrial fibrillation could be converted to sinus rhythm by a single low-energy atrial defibrillation (3 J.). After a short period of time a second intra-atrial defibrillation had to be performed in the same way because of recurrent atrial fibrillation. By this atrial shock ventricular fibrillation was induced, so that high energy external defibrillation became necessary. Analyzing the ECG a correct R-wave synchronization was found, but a rather short preceding RR interval (252 ms). In conclusion, low energy atrial defibrillation is gaining importance as a highly effective new technique to restore sinus rhythm in patients suffering from atrial fibrillation resistant to conventional therapies. Nevertheless potential risks have to be considered such as the induction of ventricular pro-arrhythmia. Therefore, a correct R-wave synchronization is obligatory and shock delivery should be withheld after short RR intervals. Future prospective randomized studies will have to show whether this new technique is really safe enough and superior to the conventional methods for restoring sinus rhythm in patients suffering from atrial fibrillation.
authors.affiliation: Medizinische Klinik III (Kardiologie), Universität Tübingen.
authors.forename: K
authors.initials: K
authors.lastname: Kettering
authors.forename: C
authors.initials: C
authors.lastname: Mewis
authors.forename: M
authors.initials: M
authors.lastname: Riemer
authors.forename: V
authors.initials: V
authors.lastname: Kühlkamp
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000503:physiopathology / Q000628:therapy*; D002036:Bundle of His / Q000503:physiopathology; D002304:Cardiac Pacing, Artificial; D017115:Catheter Ablation; D004554:Electric Countershock; D004562:Electrocardiography; D006325:Heart Atria / Q000503:physiopathology; D006801:Humans; D008297:Male; D012008:Recurrence; D019233:Retreatment; D014693:Ventricular Fibrillation / Q000209:etiology* / Q000503:physiopathology / Q000628:therapy; D014927:Wolff-Parkinson-White Syndrome / Q000503:physiopathology / Q000628:therapy*
vernacular_title: Kammerflimmern bei intraatrialer Kardioversion von Vorhofflimmern.