title: Shortened QT interval: a distinctive feature of the dysautonomia of chronic fatigue syndrome.
abstract: OBJECTIVE
  Because autonomic nervous functioning is frequently abnormal in chronic fatigue syndrome (CFS), we examined whether the corrected QT interval (QTc) in CFS differs from QTc in other populations.
  
  
  METHODS
  The QTc was calculated at the end of 10 minutes of recumbence and the end of 10 minutes of head-up tilt. In a pilot study, groups of 15 subjects, CFS, and controls, matched for age and sex, were investigated. In a second phase of the study, the QTc was measured in larger groups of CFS (n = 30) and control patients (n = 96) not matched for demographic features.
  
  
  RESULTS
  In the pilot study, the average supine QTc in CFS was 0.371 +/- 0.02 seconds and QTc on tilt, 0.385 +/- 0.02 seconds, significantly shorter than in controls (P = .0002 and .0003, respectively). Results of phase II confirmed this data.
  
  
  CONCLUSIONS
  Relative short QTc intervals are features of the CFS-related dysautonomia. The significance of this finding is discussed.
authors.affiliation: Department of Internal Medicine A, Bnai Zion Medical Center and Rappaport Family Faculty of Medicine, Technion-Israel Institute of Technology, P.O. Box 4940, Haifa 31048, Israel. naschitz@tx.technion.ac.il
authors.forename: Jochanan
authors.initials: J
authors.lastname: Naschitz
authors.forename: Madeline
authors.initials: M
authors.lastname: Fields
authors.forename: Hillel
authors.initials: H
authors.lastname: Isseroff
authors.forename: Dauod
authors.initials: D
authors.lastname: Sharif
authors.forename: Edmond
authors.initials: E
authors.lastname: Sabo
authors.forename: Itzhak
authors.initials: I
authors.lastname: Rosner
mesh_terms: D000328:Adult; D001342:Autonomic Nervous System Diseases / Q000175:diagnosis*; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D004562:Electrocardiography / Q000379:methods*; D015673:Fatigue Syndrome, Chronic / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008297:Male; D010865:Pilot Projects