title: Holter monitoring of small breed dogs with advanced myxomatous mitral valve disease with and without a history of syncope.
abstract: BACKGROUND
  Syncope is a transient loss of consciousness occasionally occurring in dogs with advanced myxomatous mitral valve disease (MMVD).
  
  
  OBJECTIVE
  (1) To study ECG changes during syncopal episodes in dogs with advanced MMVD and (2) to compare the occurrence of arrhythmias and changes in heart rate variability (HRV) between dogs with advanced MMVD with and without a history of syncope.
  
  
  METHODS
  Forty-three privately owned dogs (<15 kg) with advanced MMVD: 21 with and 22 without a history of syncope.
  
  
  METHODS
  Prospective study with dogs recruited for an evaluation including history, physical examination, echocardiography, and arrhythmia and HRV analysis performed on 24-hour Holter recordings.
  
  
  RESULTS
  A syncopal episode was observed during Holter monitoring in 4 dogs: 3 dogs had sinus rhythm and 1 dog had sinus arrest followed by escape rhythm. An arrhythmia variable representing sinus arrhythmia was significantly lower in dogs with a history of syncope than in those without (P = .008). Eight of 26 HRV variables were significantly different between dogs with and without a history of syncope.
  
  
  CONCLUSIONS
  Compared with dogs without a history of syncope, dogs with advanced MMVD and a history of syncope did not have a higher occurrence of arrhythmias, but had less sinus arrhythmia, and had changes in HRV variables representing decreased overall HRV, decreased parasympathetic, and increased sympathetic modulation of heart rate.
authors.affiliation: Department of Veterinary Clinical and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Frederiksberg, Denmark.
authors.forename: C E
authors.initials: CE
authors.lastname: Rasmussen
authors.forename: T
authors.initials: T
authors.lastname: Falk
authors.forename: A
authors.initials: A
authors.lastname: Domanjko Petrič
authors.forename: M
authors.initials: M
authors.lastname: Schaldemose
authors.forename: N E
authors.initials: NE
authors.lastname: Zois
authors.forename: S G
authors.initials: SG
authors.lastname: Moesgaard
authors.forename: B
authors.initials: B
authors.lastname: Ablad
authors.forename: H Y
authors.initials: HY
authors.lastname: Nilsen
authors.forename: I
authors.initials: I
authors.lastname: Ljungvall
authors.forename: K
authors.initials: K
authors.lastname: Höglund
authors.forename: J
authors.initials: J
authors.lastname: Häggström
authors.forename: H D
authors.initials: HD
authors.lastname: Pedersen
authors.forename: J M
authors.initials: JM
authors.lastname: Bland
authors.forename: L H
authors.initials: LH
authors.lastname: Olsen
mesh_terms: D000818:Animals; D001145:Arrhythmias, Cardiac / Q000175:diagnosis / Q000503:physiopathology / Q000662:veterinary; D004283:Dog Diseases / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000503:physiopathology*; D004285:Dogs; D004452:Echocardiography / Q000662:veterinary; D015716:Electrocardiography, Ambulatory / Q000662:veterinary*; D005260:Female; D006339:Heart Rate / Q000502:physiology; D008297:Male; D008945:Mitral Valve Prolapse / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000662:veterinary*; D013575:Syncope / Q000175:diagnosis / Q000503:physiopathology / Q000662:veterinary*
keywords: Arrhythmia; Collapse; Heart rate variability