Chapter 021. Syncope

Presyncopal symptoms vary in duration and may increase in severity until loss of consciousness occurs, or they may resolve prior to loss of consciousness if the cerebral ischemia is corrected. The differentiation of syncope from seizure is an important, sometimes difficult, diagnostic problem.Syncope may be benign when it occurs as a result of normal cardiovascular reflex effects on heart rate and vascular tone, or serious when due to a life-threatening cardiac arrhythmia.