title: Diagnosis of paroxysmal atrial fibrillation in patients with implanted pacemakers: relationship to symptoms and other variables.
abstract: BACKGROUND
  Atrial fibrillation (AF) is not always accompanied by clear-cut symptoms and symptoms suggestive of AF may not correspond to a genuine AF episode. The study prospectively evaluated the burden of asymptomatic AF episodes in pacemaker patients (for sick sinus syndrome) with a history of documented paroxysmal AF.
  
  
  METHODS
  Consecutive patients were enrolled and implanted with dual-chamber pacemakers equipped with diagnostic features for AF monitoring. Each patient was instructed about typical AF symptoms and was asked to keep a detailed log of symptoms. Stored pacemaker data were analyzed using only AF episodes >30 s.
  
  
  RESULTS
  The mean follow-up was 16 +/- 6 months and 102 patients were enrolled (73 +/- 7 years, 59 M). Thirteen patients (13%) dropped out with the development of permanent AF and their data were discarded. Twenty-three patients (26%) without device-stored AF episodes all reported at least one annotated AF episode. There were 1,245 device-stored AF episodes in 66 (74%) out of 89 patients. Patients reported 1,141 episodes of AF-related symptoms. Only 240 (21%) corresponded to a genuine device-stored AF event. The sensitivity and positive predictive value of symptoms to detect AF were respectively 19% and 21%. Episode duration, rate increase at the onset of the arrhythmia, heart disease, or antiarrhythmic drug therapy showed no statistically significant differences comparing symptomatic and asymptomatic episodes.
  
  
  CONCLUSIONS
  Many pacemaker patients with paroxysmal AF can develop AF-like symptoms in the absence of device-stored AF. AF-related symptoms have low sensitivity and low positive predictive value in patients with permanent pacemakers.
authors.affiliation: Ivrea Hospital, Ivrea, Italy. giorgio.corbucci@medtronic.com
authors.forename: Gianluca
authors.initials: G
authors.lastname: Quirino
authors.forename: Massimo
authors.initials: M
authors.lastname: Giammaria
authors.forename: Giorgio
authors.initials: G
authors.lastname: Corbucci
authors.forename: Paolo
authors.initials: P
authors.lastname: Pistelli
authors.forename: Elena
authors.initials: E
authors.lastname: Turri
authors.forename: Antonio
authors.initials: A
authors.lastname: Mazza
authors.forename: Antonello
authors.initials: A
authors.lastname: Perucca
authors.forename: Catia
authors.initials: C
authors.lastname: Checchinato
authors.forename: Maurizio
authors.initials: M
authors.lastname: Dalmasso
authors.forename: S Serge
authors.initials: SS
authors.lastname: Barold
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000175:diagnosis / Q000453:epidemiology* / Q000517:prevention & control*; D004562:Electrocardiography / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D015994:Incidence; D007558:Italy / Q000453:epidemiology; D008297:Male; D010138:Pacemaker, Artificial / Q000706:statistics & numerical data*; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors