title: [Clinical safety and efficacy of single-chamber atrial pacing in sick sinus syndrome: long-term follow-up].
abstract: OBJECTIVE
  Although atrial pacing is a more physiological mode of stimulation in sinus node dysfunction, the pacing modes most often are used DDD and VVI. The aim of our study was to demonstrate that AAI/AAIR pacing is effective and safe by analyzing the complications and mortality of this pacing mode in a long-term follow-up study.
  
  
  METHODS
  Between 1982 and 2000 definitive AAI-mode pacemakers were implanted for sinus node dysfunction in mode AAI in 160 patients. We analyzed the clinical characteristics, evolution, and complications of the AAI pacing mode during a follow-up of 5.4 4.5 years.
  
  
  RESULTS
  The sample was made up of 104 women and 56 men with an average age of 72 12 years. During follow-up, it was necessary to change the pacing mode for symptomatic bradycardia in 11 patients (annual incidence 1.2%), which was caused by second or third-degree atrioventricular block in 7 patients (annual incidence 0.8%), and chronic atrial fibrillation with bradycardia in 4 patients (annual incidence 0.4%). During follow-up, atrial arrhythmias occurred in 32 patients (annual incidence 3.7%), stroke in 4 patients (annual incidence 0.4%), and 27 patients (annual incidence 3.1%) died.
  
  
  CONCLUSIONS
  The AAI/AAIR pacing mode was safe and effective in sinus node dysfunction, with a low percentage of pacing changes required for progression to atrioventricular block, low incidence of atrial arrhythmias, stroke and low mortality during long term follow-up.
authors.affiliation: Servicio de Cardiología. Hospital Clínico Universitario de Salamanca. España. jlmori@eresmas.com
authors.forename: Jose L
authors.initials: JL
authors.lastname: Moríñigo
authors.forename: Antonio
authors.initials: A
authors.lastname: Arribas
authors.forename: Claudio
authors.initials: C
authors.lastname: Ledesma
authors.forename: Pedro L
authors.initials: PL
authors.lastname: Sánchez
authors.forename: Francisco
authors.initials: F
authors.lastname: Martín
authors.forename: Cándido
authors.initials: C
authors.lastname: Martín Luengo
mesh_terms: D000368:Aged; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D010138:Pacemaker, Artificial; D012189:Retrospective Studies; D012449:Safety; D012804:Sick Sinus Syndrome / Q000628:therapy*; D012849:Sinoatrial Node / Q000502:physiology; D016896:Treatment Outcome