What is syncope?

Syncope (pronounced "sin-ko-pea") is the medical term for fainting. Syncope is a sudden and transient loss of consciousness that has many causes. Ultimately, most causes of syncope produce a dramatic fall in blood pressure, which leads to fainting. Nearly half of all Americans will experience at least one episode of syncope during their lifetime. Syncope occurs in people of all ages from young children to elderly patients.

Dr. Imran A. Niazi, MD
Cardiac Electrophysiologist

Syncope refers to temporary loss of consciousness. This may be a benign condition, such as the common faint. It may also be the harbinger of serious health problems, including sudden death.

In 95 percent of cases, loss of consciousness occurs because the brain does not receive enough oxygen. This may be due to low blood pressure (the common faint), or it may be caused by the heart stopping or beating too quickly. These rhythm abnormalities can be fatal.

It is important to recognize that fainting in a person with a normal heart is usually not dangerous, while fainting in a person with known heart disease is associated with a risk of cardiac arrest.

Rarely, fainting occurs due to brain disorders such as epilepsy. Most of the time, the cause does not lie in the brain. The causes, diagnosis and treatment of syncope are not well understood by most physicians. If you have fainting spells, make sure you see an electrophysiologist (a heart specialist dealing with rhythm problems).

Syncope is fainting, almost fainting, or feeling dizzy or light-headed. This can be caused by serious heart-rhythm disorders and should be evaluated thoroughly.

Syncope is a medical term for fainting - or the temporary loss of consciousness and muscle tone in the body because the brain is not receiving enough blood. It can be caused by a temporary imbalance in the auto-pilot system of the body that results in temporarily reduced blood flow to the brain. Occasionally, syncope can occur after a painful injury is experienced. Fainting is very common among teenagers and young adults and does not necessarily indicate a serious heart condition. Occasionally, syncope may represent a more serious problem with the heart, particularly if it is associated with exercise or known heart conditions. Any episode of unexplained syncope should be evaluated by your physician in order to exclude the possibility of a more serious condition.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.