What is Syncope?

Syncope (sin-co-pee), which is the medical term for fainting, is a brief loss of consciousness caused by a sudden lack of blood supply to the brain. It is a temporary condition that may be associated with a drop in blood pressure, a reduction in heart rate or changes in blood volume. Up to 50 percent of the population will faint at some point in their life due to syncope, and often it is the result of an underlying medical condition that could be related to a person’s heart, nervous system or blood flow to the brain

Why does syncope occur?

The most common type of syncope – known as Reflex Syncope – is caused by a temporary disruption in the autonomic nervous system, which regulates blood pressure and heart rate.
The nerves that constrict blood vessels and maintain blood pressure withdraw their input, resulting in a drop in blood pressure. Additionally, the nerve that controls the heart rate can increase activity and cause the heart rate to fall. Both blood pressure and heart rate (may be one and not the
other) can fall to very low levels, reducing blood supply, oxygen and essential nutrients to the brain and other vital organs, ultimately causing a person to faint.

What are the common symptoms of syncope?

While symptoms vary from patient to patient and from one faint to another, the most common indicators include:

• Light-headedness
• Dizziness and nausea
• Heart palpitations
• Warm or sweaty palms
• Fading of vision or hearing
• Feeling weak or unsteady when standing

Are there risk factors associated with syncope?

While some causes of syncope are harmless, others may be serious. Heart-related causes, including abnormal heart rhythms can be fatal. You may be at risk if anyone in your family has had an unexplained sudden cardiac death. Also, if you do not have any warning signs before you faint, a sudden and unexpected fall can result in injury.

How is syncope diagnosed?

A good description by a witness, keeping a diary of events and consulting a doctor who is fully aware of the condition and takes a detailed history will lead to a correct diagnosis. If your doctor suspects a heart or brain condition is causing the syncope, diagnostic tests may be conducted to gather additional information:

Electrocardiogram (EKG) – used in the hospital to record the heart’s electrical activity during a given time.
Heart Rhythm monitor to record heart rhythms outside of hospital
Insertable cardiac monitor (ICM) – an implantable device used to monitor heart rhythms for months at a time and can remain in place for up to 3 years.
Tilt table test – used to induce a syncope episode while connected to heart and blood pressure monitors.

How can syncope be treated?

Medication and simple lifestyle modification can often prevent syncope. However, if a more serious, heart-related issue is to blame, an implantable device or surgical procedure may be warranted. A doctor will make appropriate treatment recommendations based on the individual’s condition. 

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