Sudden Cardiac Arrest (SCA) - Who's At Risk?

Sudden Cardiac Arrest (SCA) occurs abruptly and without warning, and two-thirds of SCA deaths occur without any prior indications of heart disease. In fact, SCA can happen to people of all ages and health conditions.

While signs and symptoms are often not present, there are certain risk factors for SCA, which include:

  • A previous heart attack: The majority of people who die of SCA show signs of a previous heart attack
  • A family history of sudden death, heart failure, or massive heart attack
  • An abnormal heart rate or rhythm of unknown cause
  • An unusually rapid heart rate that comes and goes
  • Episodes of fainting of unknown cause
  • Some congenital heart defect before and after surgical repair
  • A low ejection fraction (EF): The ejection fraction is a measurement of how much blood is pumped by the ventricles with each heart beat. A healthy heart pumps 55 percent or more of its blood with each beat; less than 35 percent indicates an elevated risk of SCA

About Ejection Fraction

With each heartbeat, the heart contracts (or squeezes) and relaxes. Every contraction pushes blood out of the two pumping chambers (ventricles). When the heart relaxes, the ventricles refill with blood. Ejection fraction (EF) refers to the amount, or percentage, of blood that is pumped (or ejected) out of the ventricles with each contraction.