title: Randomized comparison of anterolateral versus anteroposterior electrode position for biphasic external cardioversion of atrial fibrillation.
abstract: BACKGROUND
  In biphasic external cardioversion (CV) of atrial fibrillation (AF), the influence of different electrode positions on efficacy and incidence of early recurrent atrial fibrillation is not known. This study compared anteroposterior (AP) vs anterolateral (AL) electrode positioning.
  
  
  METHODS
  Consecutive patients referred for CV of persistent AF were randomized either to an AP or an AL electrode position. Biphasic external CV was performed with standardized electrode positions and rising energy delivery.
  
  
  RESULTS
  Both groups (N = 123, mean age 66 years, 71% male, 83% with structural cardiovascular disease or hypertension) did not differ concerning age, sex, body mass index, chronic antiarrhythmic therapy, duration of AF, left ventricular ejection fraction, and left atrial diameter. Cumulative success rates were comparable (AP 94.9% vs AL 95.2%, P = ns). First-shock efficacy did not differ (AP 78.3% vs AL 74.6%, P = ns). Early recurrent atrial fibrillation (AF relapse < 1 minute after successful CV) occurred in 8.1% (AP 11.6% vs AL 4.8%, P = ns). Mean number of shocks was 1.3 per patient with the AP configuration and 1.4 per patient with the AL configuration (P = ns). Mean cumulative energy delivery was also comparable (AP 171 WS vs AL 198 WS, P = ns).
  
  
  CONCLUSIONS
  Both electrode positions are similar in biphasic external CV of AF with regard to acute success and early recurrent atrial fibrillation. Also, the number of shocks needed and energy delivery are comparable with both electrode configurations.
authors.affiliation: Klinik für Innere Medizin III (Kardiologie, Angiologie und Internistische, Intensivmedizin), Universitätsklinikum des Saarlandes, Homburg/Saar, Germany. siaplaouras@aol.com
authors.forename: Stephanos
authors.initials: S
authors.lastname: Siaplaouras
authors.forename: Axel
authors.initials: A
authors.lastname: Buob
authors.forename: Carsten
authors.initials: C
authors.lastname: Rötter
authors.forename: Michael
authors.initials: M
authors.lastname: Böhm
authors.forename: Jens
authors.initials: J
authors.lastname: Jung
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000628:therapy*; D004554:Electric Countershock / Q000295:instrumentation / Q000379:methods*; D004566:Electrodes; D005260:Female; D006801:Humans; D008297:Male; D012008:Recurrence; D013997:Time Factors