title: Usefulness of an implantable loop recorder in patients with syncope of an unknown cause.
abstract: OBJECTIVE
  The mechanisms underlying syncope remain unknown in about 20% of patients with recurrent syncope. The implantable loop recorder (ILR) has been shown to be a useful diagnostic tool in patients with unexplained syncope even after negative initial evaluations. Nevertheless, ILR has rarely been used in clinical practice.
  
  
  METHODS
  This study included 18 consecutive patients who had an ILR implanted at our center because of recurrent unexplained syncope after extensive diagnostic tests between February 2006 and June 2011.
  
  
  RESULTS
  Diagnosis was confirmed in 10 (55.6%) of the 18 enrolled patients (13 males, 61±15 years). The confirmed diagnoses included sick sinus syndrome (n=6, 60%), advanced atrioventricular block (n=2, 20%) and ventricular tachyarrhythmia (n=2, 20%). The mean follow-up durations of the total study subjects and the diagnosed patients were 11.3±10.6 months and 5.6±9.2 months, respectively. Of the 10 diagnosed patients, 8 (80%) were diagnosed within 6 months of loop recorder implantation.
  
  
  CONCLUSIONS
  ILR may be a valuable and effective diagnostic tool for patients with unexplained syncope.
authors.affiliation: Department of Medicine, Samsung Changwon Hospital, Sungkyunkwan University School of Medicine, Changwon, Korea.
authors.forename: Gu Hyun
authors.initials: GH
authors.lastname: Kang
authors.forename: Ju Hyeon
authors.initials: JH
authors.lastname: Oh
authors.forename: Woo Jung
authors.initials: WJ
authors.lastname: Chun
authors.forename: Yong Hwan
authors.initials: YH
authors.lastname: Park
authors.forename: Bong Gun
authors.initials: BG
authors.lastname: Song
authors.forename: June Soo
authors.initials: JS
authors.lastname: Kim
authors.forename: Young Keun
authors.initials: YK
authors.lastname: On
authors.forename: Seung Jung
authors.initials: SJ
authors.lastname: Park
authors.forename: June
authors.initials: J
authors.lastname: Huh
mesh_terms: D000328:Adult; D000368:Aged; D004562:Electrocardiography / Q000295:instrumentation / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000295:instrumentation / Q000379:methods; D013575:Syncope / Q000175:diagnosis* / Q000209:etiology
keywords: Implantable loop recorder; syncope
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