Syncope (Fainting)

The sudden, transient, loss of consciousness in an individual is known as syncope or fainting. Syncope typically lasts for seconds or minutes and is usually followed by a complete recovery. Although the act of syncope can be terrifying, it is usually harmless and most likely does not signify a serious disease or a life threatening problem.

For most people, syncope occurs once or twice in a lifetime; for others, various medical conditions may lead to numerous fainting spells throughout their life. Anyone who experiences syncope should always notify a doctor immediately. If physical injury occurs as a result of fainting, then one should call 911 and head to the closest emergency room.

Syncope Causes

There are numerous causes of syncope that fall into two broad categories:

  • Cardiogenic syncope: This type of syncope is heart-related, caused by either an abnormal heart rhythm or structural damage to the heart. This is a dangerous form of syncope.
  • Non-cardiogenic syncope: This type was not caused by a heart problem, but rather a transient drop in blood pressure, heart rate, or change in vagal tone, most of which is controlled by the autonomic nervous system. In some people, despite numerous tests, no obvious cause is ever found.

Syncope Diagnosis

It is always important to see a doctor if you have fainted. The doctor will need to know the history surrounding the event, which is very important when trying to determine the cause of the syncope. For example, symptoms such as dizziness, sweating, nausea, diarrhea, vomiting, headache, visual changes, abnormal body movements, loss of control of bowel or bladder, and chest pain are important clues. In addition, it is also helpful to convey what you were doing when the event occurred. Many benign fainting spells are triggered by a vasovagal reaction (a sudden, transient drop in blood pressure resulting in a temporary loss of consciousness), which typically occurs during activities such as eating, urinating , defecating, or standing for long periods.

Medical history (including medications) and age are also important when trying to determine the cause of syncope. Older people are at higher risk for serious conditions and diseases that may lead to syncope. People with known heart conditions, alcohol or drug problems, known seizure disorders, diabetes, or neurological disorders are more likely to have fainting spells.

A variety of tests, mostly cardiovascular, are used when trying to determine the cause of syncope. Treatment for the syncope will depend on the cause. These tests include:

  • electrocardiogram (ECG or EKG)
  • event/holter monitor
  • echocardiogram
  • neurologic testing
  • tilt table testing
  • electrophysiology study.
  • implantable loop recorder (sometimes)

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