Dysautonomia and heart rate variability following severe traumatic brain injury

Brain Inj. 2006 Apr;20(4):437-44. doi: 10.1080/02699050600664715.


Primary objective: To investigate disconnection theories postulated as the cause of dysautonomia following severe traumatic brain injury (TBI) through analysis of heart rate variability (HRV).

Methods and procedures: Data were collected on age-matched subjects with and without dysautonomia (eight subjects in each group) and 16 non-injured controls. Data included injury details, continuous electrocardiograph recordings and rehabilitation outcome.

Main outcomes and results: The TBI group revealed significant differences in HRV parameters both compared to controls and between dysautonomic and non-dysautonomic subjects. Additionally, HRV parameters for dysautonomic subjects showed evidence of an uncoupling of the normal relationship between heart rate and sympathetic/parasympathetic balance. HRV changes persisted for the dysautonomia group for a mean of 14 months post-injury.

Conclusions: Dysautonomic subjects revealed prolonged uncoupling of heart rate and HRV parameters compared to non-dysautonomic subjects and controls. These findings represent direct pathophysiological evidence supporting the disconnection theory postulated to produce dysautonomia following TBI.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Autonomic Nervous System Diseases / etiology
  • Autonomic Nervous System Diseases / physiopathology*
  • Brain Injuries / complications
  • Brain Injuries / physiopathology*
  • Case-Control Studies
  • Electrocardiography
  • Female
  • Heart Rate / physiology*
  • Humans
  • Male
  • Middle Aged
  • Parasympathetic Nervous System / physiopathology
  • Sympathetic Nervous System / physiopathology