title: Pacing system malfunction is a rare cause of hospital admission for syncope in patients with a permanent pacemaker.
abstract: BACKGROUND
  Few studies have examined the prevalence of permanent pacemaker (PPM) malfunction among patients with a previously implanted pacemaker admitted to the hospital with syncope.
  
  
  OBJECTIVE
  This study sought to examine causes of syncope in patients with a previously implanted pacemaker admitted to our hospital with syncope.
  
  
  METHODS
  We retrospectively reviewed our hospital admission database for patients who had both keywords "syncope" and "pacemaker" as their diagnoses from January 1, 1995 until June 1, 2012. One hundred and sixty-two patients who were admitted to the hospital because of syncope and had a PPM implanted prior to the index syncopal episode were included. All patients had pacemakers interrogated during the admission. Two independent physicians examined the discharge summary of each patient and determined the cause of syncope in each case.
  
  
  RESULTS
  Of the 162 patients studied, eight (4.9%) were found to have pacemaker system malfunction as a cause of syncope. In 96 patients (59.2%), the cause of syncope could not be determined prior to hospital discharge. Among the identifiable causes of syncope, orthostatic hypotension was most prevalent (16%) followed by vasovagal (6%), severe aortic stenosis (4.3%), atrial arrhythmia (3.1%), acute and subacute infection (3.1%), and other less prevalent causes (3.1%).
  
  
  CONCLUSIONS
  In this study, PPM system malfunction was rarely a cause of syncope in patients admitted to the hospital with a previously implanted device.
authors.affiliation: Department of Cardiology, Hadassah-Hebrew University Medical Center, Ein Karem Campus, Jerusalem, Israel. Peter.Ofman@va.gov
authors.forename: Peter
authors.initials: P
authors.lastname: Ofman
authors.forename: Catherine
authors.initials: C
authors.lastname: Rahilly-Tierney
authors.forename: Luc
authors.initials: L
authors.lastname: Djousse
authors.forename: Adelqui
authors.initials: A
authors.lastname: Peralta
authors.forename: Peter
authors.initials: P
authors.lastname: Hoffmeister
authors.forename: J Michael
authors.initials: JM
authors.lastname: Gaziano
authors.forename: Alexey
authors.initials: A
authors.lastname: Weiss
authors.forename: Chaim
authors.initials: C
authors.lastname: Lotan
authors.forename: Shimon
authors.initials: S
authors.lastname: Rosenheck
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015984:Causality; D004868:Equipment Failure / Q000706:statistics & numerical data*; D005260:Female; D006333:Heart Failure; D006801:Humans; D007557:Israel / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial / Q000706:statistics & numerical data*; D010343:Patient Admission / Q000706:statistics & numerical data*; D015995:Prevalence; D012307:Risk Factors; D013575:Syncope / Q000453:epidemiology*