Sudden Cardiac Arrest

Chart Did you know?
Did you know that sudden cardiac arrest, also called a massive heart attack, can strike anyone, anywhere, at anytime? When AEDs are available and used quickly, most cardiac arrest victims survive. Cardiac Science is dedicated to providing solutions to help you save lives.

What is Sudden Cardiac Arrest?
Sudden cardiac arrest, commonly known as massive heart attack, kills more than 450,000 Americans each year, making it the #1 health care problem and leading cause of death in the United States. This is equivalent to the entire population of the cities of Sacramento, Kansas City, or Atlanta being wiped out in one year, or nearly one death every minute. Breast cancer, stroke, and AIDS claim fewer lives combined.

Chart In SCA, the heart suddenly stops beating normally. The electrical impulses that control the rhythm of the heart become so disorganized that the heart begins to quiver and can no longer effectively pump oxygenated blood to the brain and the body's vital organs, and death occurs within minutes. CPR cannot reverse ventricular fibrillation (VF), the chaotic cardiac rhythm most often seen in SCA victims; prompt external defibrillation is the only known effective treatment to halt sudden cardiac arrest.

What Causes Sudden Cardiac Arrest?
The most common cause of SCA is ventricular fibrillation -- a lethal arrhythmia characterized by rapid, chaotic contractions of the heart. While in ventricular fibrillation, the heart is unable to pump life-sustaining oxygenated blood to vital parts of the body, particularly the brain.

According to the American Heart Association® (AHA), some factors contributing to SCA include:

  • Coronary Heart Disease
  • Electrocution
  • Drowning
  • Choking
  • Trauma
  • Illegal drug use
Death from SCA is sudden and unexpected, occurring instantly or shortly after the onset of symptoms. While there are many contributing factors, SCA can strike people anytime, anywhere, and at any age. Even a seemingly healthy person can suffer cardiac arrest without warning. According to the American Heart Association, as many as 50% of SCA victims have no prior indication of heart disease - their first symptom is cardiac arrest. For those with a known history of heart attacks, the chance of sudden cardiac death is 4-6 times greater than that of the general population.



Why is Early Defibrillation Important?
In many cases, SCA can be reversed with early defibrillation -- the use of a defibrillator to shock the heart back into normal rhythm by means of an electric current. To be most effective, defibrillation must occur as soon as possible after the onset of SCA.
  • According to the AHA, each minute of delay in delivering a defibrillation shock to a cardiac arrest victim reduces the chances of survival by 10 percent.
  • The average response time nationally for emergency medical personnel equipped with defibrillators is 10 minutes, making access to defibrillators on-site or in first-responder vehicles (police cars, fire trucks, etc.) extremely important.
  • Even in the hospital setting, traditional resuscitation procedures many times result in significant delays before an SCA victim receives defibrillation therapy; consequently, survival averages from in-hospital sudden cardiac arrests are only 15%.
  • Cardiopulmonary resuscitation (CPR) works to temporarily circulate blood to vital organs; however, CPR cannot restore a patient's heart to a healthy rhythm. The AHA states that the definitive survival treatment for an SCA victim is a defibrillation shock.
  • Published studies have proven that early defibrillation, within the first few minutes of SCA, can save up to 74 percent of victims.