Pathophysiology
Syncope results from a temporary reduction in cerebral perfusion. Although in a significant proportion of cases (up to 50%) no underlying pathology is identified, there are a number of recognised causes of syncope:
| Classification of Syncope | |
|---|---|
| Neurally mediated syncope | Vasovagal (common faint), carotid sinus syncope, Situational – e.g. cough, sneeze, GI stimulation, micturition, post prandial |
| Orthostatic | Drug effects Volume depletion Autonomic failure – e.g. Parkinson’s disease, diabetic neuropathy |
| Cardiac arrythmias | E.g. SVT, VT, Inherited syndromes (long / short QT, Brugada, WPW) |
| Structural cardiac disease | Ventricular failure Aortic stenosis HOCM |
| Cerebrovascular | Vascular steal |
We will look at each of these on the next page.
great revision