17. Neurally Mediated Syncope

  1. David H. Bennett MD FRCP

Published Online: 1 NOV 2012

DOI: 10.1002/9781118432389.ch17

Bennett's Cardiac Arrhythmias: Practical Notes on Interpretation and Treatment, Eighth Edition

Bennett's Cardiac Arrhythmias: Practical Notes on Interpretation and Treatment, Eighth Edition

How to Cite

Bennett, D. H. (2013) Neurally Mediated Syncope, in Bennett's Cardiac Arrhythmias: Practical Notes on Interpretation and Treatment, Eighth Edition, John Wiley & Sons, Ltd, Oxford. doi: 10.1002/9781118432389.ch17

Author Information

  1. Senior Consultant Cardiologist, University Hospital of South Manchester, Manchester, UK

Publication History

  1. Published Online: 1 NOV 2012
  2. Published Print: 14 JAN 2013

ISBN Information

Print ISBN: 9780470674932

Online ISBN: 9781118432389

SEARCH

Keywords:

  • Carotid sinus syndrome;
  • Malignant vasovagal syndrome;
  • Neurally mediated syncope;
  • Postural orthostatic tachycardia syndrome (POTS);
  • Tilt-table test;
  • Vasovagal syndrome

Summary

Vasovagal and carotid sinus syndromes are due to abnormal autonomic nervous system reflexes that can cause syncope due to bradycardia and/or hypotension. The malignant vasovagal syndrome, also termed neurocardiogenic syncope, is characterised by recurrent, abrupt syncope when sitting or standing, and a positive tilt-table test that can be used to demonstrate the cardioinhibitory and/or vasodepressor elements of the syndrome. Pacing may prevent syncope when caused by the former element but will not influence symptoms if due to the latter. A generous intake of both water and salt can be effective in preventing symptoms.

The diagnosis of carotid sinus syndrome is made in patients who suffer from near-syncope or syncope in whom carotid sinus massage causes sinus arrest or complete AV block for 3 s or more.

‘Situational faints’ are triggered by a variety of factors such as sight of blood, venepuncture, pain, emotion or oppressive environment.