Syncope pp 227-240 | Cite as

The Autonomic Laboratory for Evaluating Syncope/Collapse: Investigations and Their Implications

  • Christopher J. Mathias
  • Andrew P. Owens
  • Valeria Iodice


Syncope and collapse may result from a number of causes—neurological (autonomic and non-autonomic), cardiac, and metabolic. In addition, syncopal behaviour (loss of postural tone and unresponsiveness) may manifest in the form of a conversion disorder (functional non-syncopal collapse or pseudosyncope). There are many autonomic nervous system causes of syncope and they vary across the entire age spectrum. Intermittent and transient autonomic dysfunction, classed as autonomic mediated syncope (AMS), include those in all age groups (e.g., vasovagal syncope), in the >50’s (e.g., carotid sinus hypersensitivity/syndrome), and in different predisposing situations (situational syncope). An increasingly recognised new millennium autonomic cause of pre-syncopal symptoms (principally palpitations and dizziness) when upright is the postural tachycardia syndrome (PoTS), that can be associated with fainting. Many diseases and disorders within the brain, spinal cord, or periphery, although less common can result in autonomic damage and failure, often with orthostatic (postural) hypotension. Drugs also can cause or contribute to syncope. This chapter will provide an overview of the role of the autonomic laboratory in the evaluation of syncope/collapse, with the key aims being able to confirm (or exclude) an autonomic condition, to ascertain the cause or associated disorder contributing, and to determine additional factors that aid the management of autonomic mediated syncope/collapse.


  1. 1.
    Soteriades ES, et al. Incidence and prognosis of syncope. N Engl J Med. 2002;347(12):878–85. Scholar
  2. 2.
    Ganzeboom KS, et al. Prevalence and triggers of syncope in medical students. Am J Cardiol. 2003;91(8):1006–8. Scholar
  3. 3.
    Puppala VK, Dickinson O, Benditt DG. Syncope: classification and risk stratification. J Cardiol. 2014;63(3):171–7.CrossRefGoogle Scholar
  4. 4.
    Kapoor WN. Evaluation and outcome of patients with syncope. Medicine. 1990;69(3):160–75. Scholar
  5. 5.
    Close JCT, et al. Fall in the older population: a pilot study to assess those attended by London Ambulance Service but not taken to A&E. Age Ageing. 2002;31(6):488–9. Scholar
  6. 6.
    Mahmood S, et al. The Framingham heart study and the epidemiology of cardiovascular disease: a historical perspective. Lancet. 2014;383(9921):999–1008. Scholar
  7. 7.
    Mathias CJ, Deguchi K, Schatz I. Observations on recurrent syncope and presyncope in 641 patients. Lancet. 2001;357(9253):348–53.CrossRefGoogle Scholar
  8. 8.
    Mathias CJ, Iodice V, Low DA, Bannister R. Investigation of autonomic disorders. In: Mathias CJ, Bannister R, editors. Autonomic failure: a textbook of clinical disorders of the autonomic nervous system. 5th ed. Oxford: Oxford University Press; 2013.CrossRefGoogle Scholar
  9. 9.
    Humm AM, Mathias CJ. Abnormal cardiovascular responses to carotid sinus massage also occur in vasovagal syncope - Implications for diagnosis and treatment. Eur J Neurol. 2010;17(8):1061–7. Scholar
  10. 10.
    Mathias CJ, et al. Frequency of family history in vasovagal syncope. Lancet. 1998;352(9121):33–4. Scholar
  11. 11.
    Mcgrady A, et al. Psychological and physiological factors associated with tilt table testing for neurally mediated syncopal syndromes. Pacing Clin Electrophysiol. 2001;24(3):296–301. Scholar
  12. 12.
    Mathias CJ, et al. Familial vasovagal syncope and pseudosyncope: observations in a case with both natural and adopted siblings. Clin Auton Res. 2000;10(1):43–5. Scholar
  13. 13.
    Mathias CJ, et al. Postural tachycardia syndrome – current experience and concepts. Nat Rev Neurol. 2012;8(1):22–34. Scholar
  14. 14.
    Mathias CJ, et al. Clinical, autonomic and therapeutic observations in two siblings with postural hypotension and sympathetic failure due to an inability to synthesize noradrenaline from dopamine because of a deficiency of dopamine ß hydroxylase. Q J Med. 1990;75(278):617–33.PubMedGoogle Scholar
  15. 15.
    Vichayanrat E, et al. Twenty-four-hour ambulatory blood pressure and heart rate profiles in diagnosing orthostatic hypotension in Parkinson’s disease and multiple system atrophy. Eur J Neurol. 2017;24(1):90–7. Scholar

Copyright information

© Springer Nature Switzerland AG 2020

Authors and Affiliations

  • Christopher J. Mathias
    • 1
    • 2
    • 3
  • Andrew P. Owens
    • 4
  • Valeria Iodice
    • 1
    • 2
    • 5
  1. 1.Queen Square Institute of Neurology, University College LondonLondonUK
  2. 2.Autonomic & Neurovascular Medicine Centre, Hospital of St John & St ElizabethLondonUK
  3. 3.Lindo Wing, St Mary’s Hospital, Imperial College Healthcare TrustLondonUK
  4. 4.Department of Old Age Psychiatry, Institute of Psychiatry, Psychology and Neuroscience, King’s CollegeLondonUK
  5. 5.Autonomic Unit, National Hospital for Neurology and Neurosurgery, Queen Square, UCLH TrustLondonUK

Personalised recommendations