Keywords: syncope, vasovagal, orthostatic, blood pressure (PubMed Search)
Vasovagal syncope is a subtype of neurally mediated syncope, and it is distinctly different from orthostatic hypotension.
Patients with orthostatic syncope have severe orthostatic hypotension that results in transient loss of consciousness immediately or within moments of standing up. This is different from neurally mediated syncope, which develops gradually under conditions of prolonged orthostatic stress such as standing for several minutes. Tilt table testing is useful for true orthostatic syncope, but not for neurally mediated syncope. In addition, checking for “orthostatic hypotension” may not capture patient with orthostatic syncope, because the hypotension occurs so quickly after standing up. Of note, patients may still have orthostatic tachycardia or intolerance with neurally mediated syncope.