title: Coronary sinus pacing prevents induction of atrial fibrillation.
abstract: BACKGROUND
  Atrial fibrillation (AF) is due to reentry, and its incidence has been shown to decrease after dual-site atrial or biatrial pacing. We investigated whether a simpler pacing approach via the distal coronary sinus (CSd) could eliminate AF inducibility by high right atrial (HRA) extrastimuli (APDs). We based our hypothesis on our previous observation that AF inducibility by HRA APDs was associated with conduction delays to the posterior triangle of Koch, whereas AF was never induced with CSd APDs, which were associated with minimal intra-atrial conduction delays.
  
  
  RESULTS
  Programmed electrical stimulation was performed from the high right atrium and CSd, and bipolar recordings were obtained from the high right atrium, His bundle, posterior triangle of Koch, and coronary sinus. In 13 patients (age, 44+/-18 years), AF was reproducibly induced with a critically timed HRA APD (220+/-22 ms) delivered during HRA pacing. AF was not induced in any of the patients when HRA APDs were delivered during CSd pacing at the same critical coupling intervals. Coronary sinus APDs delivered during HRA pacing also were not associated with AF induction. The APD coupling interval measured at the posterior triangle of Koch during CSd pacing was significantly prolonged compared with the one measured during HRA pacing and AF induction (381+/-58 versus 263+/-37 ms; P<.0001).
  
  
  CONCLUSIONS
  We propose that CSd pacing suppresses the propensity of HRA APDs to induce AF by limiting their prematurity at the posterior triangle of Koch and not allowing local conduction delay and local reentry to occur.
authors.affiliation: Harvard-Thorndike Institute of Electrophysiology, Cardiovascular Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Mass 02215, USA.
authors.forename: P
authors.initials: P
authors.lastname: Papageorgiou
authors.forename: F
authors.initials: F
authors.lastname: Anselme
authors.forename: C J
authors.initials: CJ
authors.lastname: Kirchhof
authors.forename: K
authors.initials: K
authors.lastname: Monahan
authors.forename: C A
authors.initials: CA
authors.lastname: Rasmussen
authors.forename: L M
authors.initials: LM
authors.lastname: Epstein
authors.forename: M E
authors.initials: ME
authors.lastname: Josephson
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001281:Atrial Fibrillation / Q000209:etiology / Q000517:prevention & control*; D004562:Electrocardiography; D005260:Female; D006325:Heart Atria / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial; D013615:Tachycardia, Sinoatrial Nodal Reentry / Q000150:complications / Q000517:prevention & control*