CANet > Our Work > Research > Syncope


Dr. Robert Sheldon

The syncope research track aims to streamline care for patients with recurrent syncope to achieve a 30% reduction in health care costs attributable to syncope over 10 years while achieving measurable improvements in overall mortality, morbidity, and quality of life.

CANet Highlight

CANet investigators developed “The Canadian Syncope Risk Score” to identify low-risk syncope patients in the Emergency Department, avoiding unnecessary hospitalization. Through the implementation of this tool, the optimal management of syncope patients will be enhanced by:

  • Risk-stratification for early disposition of the very low-risk and low-risk patients and out of hospital monitoring for those at risk of arrhythmia
  • Diversion of the very-low risk patients to the ‘rapid referral syncope clinics’ at the community level by Emergency Medical Services (EMS)
  • These strategies will reduce syncope Emergency Department visits and hospitalization by 30%.


Transient Loss of Consciousness

Syncope is a transient loss of consciousness, described as fainting or passing out. It usually relates to a temporary insufficient flow of blood to the brain. Syncope is a common condition, which can occur at any age and in people without other medical problems.

Neurally mediated syncope (NMS), the most frequent cause of fainting, is benign. It is most common in children or young adults but can occur at any age. If this type of syncope is prolonged, it can trigger a seizure.

Cardiac syncope is caused by a heart or blood vessel condition that affects blood flow to the brain. These conditions can include arrhythmia, structural heart disease, blockages in the cardiac blood vessels, valve disease, aortic stenosis, blood clot, or heart failure.


Syncope can result from a sudden drop in blood pressure or heart rate, or changes in the amount of blood in areas of your body (such as from a violent coughing fit).

Syncope can have cardiovascular, neurological, or psychiatric causes. However, the most common cause is an overreaction of the body to certain triggers, such as the sight of blood or extreme emotional distress. It can also be caused by overheating, dehydration, heavy sweating, or exhaustion.

Syncope may suggest a serious disorder if:

  • It occurs with exercise
  • It is associated with palpitations or irregularities of the heart
  • There is a family history of recurrent syncope or sudden death.


  • The majority of children and young adults with syncope have no structural heart disease or significant arrhythmia. A careful physical examination by a physician, including blood pressure and heart rate measured lying and standing, is generally the only evaluation required.

  • In other cases, an electrocardiogram is used to test for abnormal heart rhythms. Other tests, such as an echocardiogram, treadmill stress test or Halter monitor, may be needed to rule out other cardiac causes of syncope.


  • Blacking out
  • Feeling lightheaded
  • Falling for no reason

  • Dizziness
  • Fainting, especially after eating or exercising
  • Changes in vision, such as seeing spots or tunnel vision.


  • Some people may respond to medication.

  • To help prevent syncope, people with NMS should be on a higher salt diet and drink plenty of fluids to avoid dehydration and maintain blood volume. They should watch for the warning signs of fainting – dizziness, nausea and sweaty palms – and sit or lie down if they feel the warning signs.

Our Impact

Working together, CANet members including our Network investigators, partners, and patients aim to REDUCE syncope hospitalization and emergency department visits by 30%. Below are some of the CANet-funded studies helping us achieve our goals.