Síndromes neuralmente mediadas

Abstract

A syncope is a transient loss of consciousness because of reduced brain blood flow with loss of postural tonus followed by fast and spontaneous recovery. It is a common medical condition that accounts for up to 6% of hospitalizations, 3% of emergency consultancy episodes and high recurrence rate (34%) 1 . The medical term “syncope” comes from the Greek “syncopa”, meaning “to cut short” or “faint” in English and just “faint” in Portuguese. Hippocrates, one thousand years before Christ, reported that patients who suffered frequent faints usually died, whereas Engel reports that the single difference between syncope and sudden death is the fact that the patient wakes up in the first case 2 . At the inicial syncope evaluation, the physician should try to distinguish potentially fatal causes, such as hypertrophic cardiomyopathy; aortic stenosis; severe coronary insufficiency; total or advanced atrioventricular blockage; and sustained ventricular tachycardia from autonomic dysfunctions/disorders. It is known that syncopes in cardiac patients are related to a high mortality rate, whereas vasovagal syncopes point to increased morbidity 1,3,4