Syncope

Syncope is a sudden, temporary loss of consciousness caused by a brief reduction in blood flow to the brain. It primarily involves the cardiovascular system, which controls blood circulation and heart function. When the brain does not receive enough oxygen-rich blood, a person may faint or pass out. This condition can happen due to various reasons such as dehydration, low blood pressure, or heart problems. The main health impact is the risk of injury from falling during the fainting episode. Recognizing warning signs like dizziness or lightheadedness before fainting is important. Syncope episodes are usually brief, and consciousness returns quickly once blood flow is restored.

Syncope is defined as a transient loss of consciousness and postural tone due to global cerebral hypoperfusion, characterized by rapid onset, short duration, and spontaneous complete recovery. The core pathology involves a sudden drop in cerebral blood flow, often caused by cardiac arrhythmias, vasovagal reflexes, or orthostatic hypotension. It is a common clinical problem with significant diagnostic and prognostic implications, as it may indicate underlying cardiovascular disease or neurological disorders. The mechanism can be broadly categorized into neurally mediated, cardiac, and orthostatic causes. Identifying the etiology is crucial because cardiac syncope carries a higher risk of morbidity and mortality. Clinical evaluation focuses on history, physical examination, and targeted diagnostic testing to differentiate benign from life-threatening causes.