title: Effect of electrode position on outcome of low-energy intracardiac cardioversion of atrial fibrillation.
abstract: The aim of this study was to evaluate the new method of low-energy, catheter-based intracardiac cardioversion in patients with chronic atrial fibrillation (AF) and to compare 2 different lead positions. Accordingly, we prospectively studied 80 consecutive patients with chronic AF (9.8 +/- 7.9 months) who were randomly assigned to undergo internal cardioversion either via defibrillation electrodes placed in the right atrium and coronary sinus (coronary sinus group) or via defibrillation electrodes placed in the right atrium and left pulmonary artery (pulmonary artery group). Intracardiac shocks were delivered by an external defibrillator synchronized to the QRS complex. After conversion, all patients were treated orally with sotalol (mean daily dose, 189 +/- 63 mg/day). For conversion to sinus rhythm, the overall mean energy requirement was 5.6 +/- 3.1 J. In the coronary sinus group, cardioversion was achieved in 35 of 38 patients at a mean energy level of 4.1 +/- 2.3 J (range 1.0 to 9.9), and in the pulmonary artery group in 39 of 42 patients with 7.2 +/- 3.1 J (range 2.5 to 14.8). Although there was no difference with regard to success rate, the energy differed significantly between the 2 groups (p < 0.01). Mean lead impedance was 56.4 +/- 7.0 omega and 54.6 +/- 8.5 omega, respectively (p = NS). No serious complications were observed in either lead group. At a mean follow-up of 14.2 +/- 7.0 months, 54% and 56%, respectively, of patients who had been converted successfully remained in sinus rhythm. Thus, low-energy biphasic shocks delivered between the right atrium and coronary sinus or pulmonary artery are equally effective for cardioversion of patients with chronic AF. The energy requirements for conversion from a pulmonary artery electrode position are higher than for the coronary sinus position.
authors.affiliation: 1. Medizinische Klinik, Klinikum rechts der Isar, Technischen Universitat München, Germany.
authors.forename: E
authors.initials: E
authors.lastname: Alt
authors.forename: C
authors.initials: C
authors.lastname: Schmitt
authors.forename: R
authors.initials: R
authors.lastname: Ammer
authors.forename: A
authors.initials: A
authors.lastname: Plewan
authors.forename: F
authors.initials: F
authors.lastname: Evans
authors.forename: J
authors.initials: J
authors.lastname: Pasquantonio
authors.forename: T
authors.initials: T
authors.lastname: Ideker
authors.forename: G
authors.initials: G
authors.lastname: Lehmann
authors.forename: K
authors.initials: K
authors.lastname: Pütter
authors.forename: A
authors.initials: A
authors.lastname: Schömig
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000368:Aged; D000889:Anti-Arrhythmia Agents / Q000008:administration & dosage / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000628:therapy*; D006328:Cardiac Catheterization / Q000295:instrumentation; D002908:Chronic Disease; D003331:Coronary Vessels; D004553:Electric Conductivity; D004554:Electric Countershock / Q000295:instrumentation* / Q000379:methods; D017097:Electric Impedance; D004562:Electrocardiography; D004567:Electrodes, Implanted; D005260:Female; D005500:Follow-Up Studies; D006325:Heart Atria; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011651:Pulmonary Artery; D013015:Sotalol / Q000008:administration & dosage / Q000627:therapeutic use; D016896:Treatment Outcome
chemical_list: D000889:Anti-Arrhythmia Agents; D013015:Sotalol