title: Sleep related bradyarrhythmic events and heart rate variability in apparently healthy individuals.
abstract: OBJECTIVE
  It is thought that abnormal cardiac impulses of the autonomic nervous system during sleep are responsible for sleep-related bradyarrhythmias. Despite a proposed common etiopathogenesis and having common name of "sleep-related bradyarrhythmias," precise importance of sinoatrial or atrioventricular (AV) node involvement remains elusive. This study aimed to determine whether there is a difference in sleeprelated bradyarrhythmias from the point of view of heart rate variability (HRV).
  
  
  METHODS
  Patients were evaluated using 24-hour Holter electrocardiogram monitor. After careful medical evaluation, apparently healthy individuals with sleep-related sinus pauses ≥2 seconds on at least 1 occasion or those in whom Mobitz type I AV block occurred were included. Frequency and time domain analyses were conducted for daytime, nighttime, and 24-hour period.
  
  
  RESULTS
  Total of 37 patients with sinus pause(s), 40 patients with Mobitz type I AV block(s), and 40 healthy controls were included. On HRV analyses, all time and frequency domain parameters were better in sinus pause group for daytime, nighttime, and 24-hour average (p<0.05 for all). Results of heart rate-corrected HRV analyses still showed significantly better total power (TP) and very low frequency (VLF) in the sinus pause group compared with AV block group (TP: 7.1x10-3 vs. 5.4x10-3, p=0.011; VLF: 4.9x10-3 vs. 3.7x10-3, p=0.007).
  
  
  CONCLUSIONS
  Despite proposed common autonomic mechanisms, sleep-related sinus pause cases demonstrated better HRV profile in comparison with Mobitz type I AV block.
authors.affiliation: Department of Cardiology, Dışkapı Yıldırım Beyazıt Training and Research Hospital; Ankara-Turkey. drtolgacim@hotmail.com.
authors.forename: Tolga
authors.initials: T
authors.lastname: Çimen
authors.affiliation: Department of Cardiology, Dışkapı Yıldırım Beyazıt Training and Research Hospital; Ankara-Turkey.
authors.forename: Hamza
authors.initials: H
authors.lastname: Sunman
authors.affiliation: Department of Cardiology, Dışkapı Yıldırım Beyazıt Training and Research Hospital; Ankara-Turkey.
authors.forename: Mehmet
authors.initials: M
authors.lastname: Erat
authors.affiliation: Department of Cardiology, Dışkapı Yıldırım Beyazıt Training and Research Hospital; Ankara-Turkey.
authors.forename: Tolga Han
authors.initials: TH
authors.lastname: Efe
authors.affiliation: Department of Cardiology, Dışkapı Yıldırım Beyazıt Training and Research Hospital; Ankara-Turkey.
authors.forename: Ahmet
authors.initials: A
authors.lastname: Akyel
authors.affiliation: Department of Cardiology, Dışkapı Yıldırım Beyazıt Training and Research Hospital; Ankara-Turkey.
authors.forename: Murat
authors.initials: M
authors.lastname: Bilgin
authors.affiliation: Department of Cardiology, Dışkapı Yıldırım Beyazıt Training and Research Hospital; Ankara-Turkey.
authors.forename: Sadık
authors.initials: S
authors.lastname: Açıkel
authors.affiliation: Department of Cardiology, Dışkapı Yıldırım Beyazıt Training and Research Hospital; Ankara-Turkey.
authors.forename: Mehmet
authors.initials: M
authors.lastname: Doğan
authors.affiliation: Department of Cardiology, Dışkapı Yıldırım Beyazıt Training and Research Hospital; Ankara-Turkey.
authors.forename: Ekrem
authors.initials: E
authors.lastname: Yeter
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001919:Bradycardia / Q000150:complications / Q000503:physiopathology*; D003430:Cross-Sectional Studies; D015716:Electrocardiography, Ambulatory; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012893:Sleep Wake Disorders / Q000150:complications*; D055815:Young Adult