title: [Maintenance of AAI(R) mode at the time of generator replacement].
abstract: BACKGROUND
  In isolated sinus node disease single lead atrial stimulation is recommended. However, an inherent risk includes emerging AV node disturbances with serious bradycardia in the follow-up. This possible scenario frequently results in the implantation of an additional ventricular lead.
  
  
  METHODS
  In this single-centre retrospective study the interval between 1982 and 2007 was analysed. During this period a total of 6,309 antibradycardia pacemakers were implanted for the first time. Ten percent (n=631) of these devices were single lead atrial pacemakers for treatment of the sick sinus syndrome (SSS). In these 26 years 136 pacemaker replacement operations were performed. During this procedure a thorough reevaluation of the stimulation mode was done.
  
  
  RESULTS
  In 80.6% (n=112) AAI(R) was continued, in 10.1% (n=14) the system was upgraded to DDD(R), and in 9.3% the mode was changed to VVI(R). There were no significant differences in the lifetime of the AAI(R) pacemakers up to the time of this operation: 7.9 vs 6.3 vs 7.0 years.
  
  
  CONCLUSIONS
  The single lead atrial pacing mode in SSS is mostly safe also in the long term. A premature change of stimulation mode is rarely necessary.
authors: eckartwunderlich@web.de.
authors: E
authors: E
authors: Wunderlich
authors: H
authors: H
authors: Schindler
authors: A
authors: A
authors: Hetze
authors: C
authors: C
authors: Wunderlich
mesh_terms: D001919:Bradycardia / Q000628:therapy*; D058406:Cardiac Resynchronization Therapy; D004567:Electrodes, Implanted; D006325:Heart Atria / Q000503:physiopathology; D006339:Heart Rate / Q000502:physiology; D006352:Heart Ventricles / Q000503:physiopathology; D006801:Humans; D010138:Pacemaker, Artificial; D011474:Prosthesis Design; D019233:Retreatment; D012189:Retrospective Studies; D012804:Sick Sinus Syndrome / Q000503:physiopathology / Q000628:therapy*