Sudden Cardiac Arrest advice

Who is at risk for SCA?

Unfortunately, anyone can suffer sudden cardiac arrest. SCA is unpredictable and can happen to anyone, anytime, anywhere -- even teenagers. Although pre-existing heart disease is a common cause of cardiac arrest, many victims have never had a heart problem. Risk does increase with age.

Without immediate treatment, only 5-10 percent of people survive SCA. But survival rates above 50 per cent have been achieved in places that have successfully implemented Automated External Defibrillator (AED) programs. Survival rates can climb even higher when the person is treated within three minutes of cardiac arrest

In most cases, sudden cardiac arrest (SCA) strikes without prior symptoms. However, the following risk factors increase your potential for SCA:

  • Previous SCA episode(s):
    A previous episode often predicts another occurrence. Prevention is critical to survival.
  • Previous heart attack or Myocardial Infarction: A heart attack damages the heart muscle and it can cause abnormal heart rhythms (arrhythmias). It may feel like your heart is racing, or beating out of rhythm. There may be no symptoms, but some arrhythmias can be life-threatening and cause SCA.
  • Heart failure (heart pumps poorly).
  • Ejection fraction (EF) indicator of 40 or less: Your ejection fraction is the proportion, or fraction, of blood pumped out of your heart with each beat. A normal EF is 55 percent or higher. Your doctor can order a simple test such as an echocardiogram that creates a moving picture of your heart that shows how well your heart is pumping and measure your EF. If your EF is abnormally low, as a result of a previous heart attack or heart failure, you may need further tests to see if you have an abnormal heart rhythm.
  • Abnormal heart rhythms: If your ejection fraction is 40 percent or less, further testing is warranted to verify the risk associated with the rhythm disorder. If your heart arrhythmia comes and goes, there are special monitors you can wear or carry to record your heart's electrical activity.
  • Previous history of heart disease or heart rhythm disorders.
  • Family history of SCA.
  • Unexplained fainting episodes.

Risk factors for sudden cardiac death in the community (ESC guidelines)

Non-modifiable Risk Factors Modifiable Risk Factors
Male Gender
Family History of Coronary Heart Disease
Genetic Factors
Increased LDL Cholesterol
Diabetes Mellitus


See your physician

If you or someone you know has any risk factors of sudden cardiac arrest, do not wait. Your physician can provide you with the next steps and options for care. Talk to your doctor about your risk factors today and ask if a referral to a heart rhythm specialist is appropriate for you.

A heart rhythm specialist is a cardiologist or electrophysiologist who diagnoses and treats cardiac arrhythmias - heartbeats that are too slow, too fast or irregular - that may lead to sudden cardiac arrest.

Proactive and informed management of your heart's health can mean the difference between long-term survival, unchecked progression of heart disease and death.

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