Abstract

Syncope phenomena is an abrupt and transient loss of consciousness leading to interruption of awareness of one’s surroundings and falls with risk of injury. Syncope is often followed by complete and usually rapid spontaneous recovery. It is said that half of all individuals experience syncopal event at least once during their life. The condition can occur at any age and happens in people with and without other medical problems. The underlying mechanism is global hypoperfusion of both the cerebral cortices or focal hypoperfusion of the reticular activating system. Decreased cerebral perfusion is common to most causes of syncope. Cessation of a cerebral perfusion for even a short time, as 3-5 seconds, could result in syncope. Decreased cerebral perfusion may occur as a result of decreased both cardiac output or systemic vascular resistance. There are several different types of syncope which derive from different etiologies such as the neurally-mediated (reflex) syncope, orthostatic hypotension which may be caused by dehydration or due to medication and the cardiovascular derived syncopal events which are most dangerous ones. The most common syncope event is called vasovagal syncope. Such commonfaint may be experienced by normal persons with no evidence of any heart disease. Vasovagal syncope is the most common cause of such phenomena in young adults. As in other forms of neurally-mediated reflex syncope, it is due to systemic hypotension resulting in a transient period of inadequate cerebral blood flow. Vasovagal syncope can be preceded by such symptoms as pallor, nausea, sweating or heart palpitations. It often occurs when person is exposed to the prolonged standing, heat, emotional stress, trauma or pain etc. During and after the syncopal event the headache, confusion, discomfort and chest pain may occur, but there are many events that end up with no side effects at all. Overall, even if the syncopal event may have no side effects, it impacts patient quality of life and often may lead to dramatic consequences of self-injury or risk of danger for surrounding people (e.g. syncopal event occurring while driving a car). Monitoring cardiovascular events in syncope patients is tough and challenging issue.

Authors (3)