title: Effects of right atrial pacing preference in prevention of paroxysmal atrial fibrillation: Atrial Pacing Preference study (APP study).
abstract: BACKGROUND
  Several preliminary studies have indicated that atrial pacing can prevent atrial tachyarrhythmias. The suggested mechanisms by which pacing may be effective include suppression of premature atrial beats.
  
  
  RESULTS
  The Atrial Pacing Preference (APP; Guidant, St Paul, MN, USA) algorithm allows the pacemaker to maintain a pacing rate slightly higher than the sinus rate. The preventive effects of APP on paroxysmal atrial fibrillation (AF) were studied in 51 patients (70+/-11 years). Nine patients did not complete the protocol. The pacemaker was programmed in random order to APP off and APP on at 3 different settings (ie, 8, 16 and 32 cycles) for 4 weeks each, using a cross-over design. Percentage atrial pacing was lower in APP off than at the other settings. Premature beat counts were greater in APP off than at the other settings. There was a significant difference in mode switch episode counts between APP off and the most effective setting (3,818+/-15,356 vs 596+/-1,719; p<0.01).
  
  
  CONCLUSIONS
  The APP algorithm is a promising method for preventing atrial tachyarrhythmia in patients with an implanted pacemaker and AF. Optimizing the setting of the APP algorithm is an important issue in the prevention of AF.
authors.affiliation: Division of Cardiology, Yokohama City University Hospital, Yokohama, Japan. h-ogawa@fukuhp.yokohama-cu.ac.jp
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Ogawa
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Ishikawa
authors.forename: Kouhei
authors.initials: K
authors.lastname: Matsushita
authors.forename: Katsumi
authors.initials: K
authors.lastname: Matsumoto
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Ishigami
authors.forename: Teruyasu
authors.initials: T
authors.lastname: Sugano
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Uchino
authors.forename: Satoshi
authors.initials: S
authors.lastname: Umemura
authors.forename: Shinichi
authors.initials: S
authors.lastname: Sumita
authors.forename: Kazuo
authors.initials: K
authors.lastname: Kimura
authors.forename: Takeshi
authors.initials: T
authors.lastname: Nakagawa
authors.forename: Makoto
authors.initials: M
authors.lastname: Shimizu
authors.forename: Hideo
authors.initials: H
authors.lastname: Nishikawa
authors.forename: Atsunobu
authors.initials: A
authors.lastname: Kasai
authors.forename: Yukio
authors.initials: Y
authors.lastname: Kioka
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D001281:Atrial Fibrillation / Q000517:prevention & control*; D018880:Atrial Premature Complexes / Q000628:therapy; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial; D011446:Prospective Studies; D012804:Sick Sinus Syndrome / Q000628:therapy; D013612:Tachycardia, Ectopic Atrial / Q000628:therapy*; D016896:Treatment Outcome