Definitions by Dr. Dames – Sudden Cardiac Arrest

What is Sudden Cardiac Arrest?

While we like to romanticize the heart, the truth is the heart is nothing more than a pump, and its job is to pump blood to the brain and vital organs. Blood carries the necessary nutrients and oxygen to keep us alive. Sudden Cardiac Arrest (SCA) occurs when the heart suddenly stops pumping blood effectively, and a person whose heart suddenly stops pumping blood effectively loses consciousness and stops breathing normally. It is frequently caused by an abnormal, chaotic heart rhythm called ventricular fibrillation where the heart is just quivering and not moving blood through the heart and out to the body.

Once SCA occurs, the brain will start to die within 4-6 minutes of being deprived of oxygen, so immediate help is vital. For each minute which passes without oxygen being delivered to the brain and body, there is an incremental 10% decrease in the chance of survival. The average response time for paramedics can be anywhere from 8-15 minutes. Since the brain starts to die within 4-6 minutes of being deprived of oxygen, it is frequently too late to save the person and have them remain neurologically intact by the time paramedics arrive. Immediate CPR and early defibrillation using an Automated External Defibrillator (AED) can make the difference!

It may surprise you to know Sudden Cardiac Arrest is the single leading cause of death in America. It is killing more than 900 people in this country every day. More people die from SCA every year than all the deaths from breast cancer, prostate cancer, lung cancer and AIDs combined. It is a huge public health problem in this country, and it can be treated by you! Yes, you!

Who is at Risk?

Sudden Cardiac Arrest can happen to anyone, anywhere, at any time, but research shows African Americans and Hispanics have a higher risk than Caucasians. Also, a prior heart attack or heart failure is a major risk factor for SCA; and a family history of SCA in a parent, sibling or offspring is associated with a two-fold increase in SCA.

What are the Leading Causes?

There are many causes of Sudden Cardiac Arrest. The most common are:

1.) Heart Attack, also called a Myocardial Infarction

2.) Heart Muscle Thickening, such as Hypertrophic Cardiomyopathy and Arrhythmogenic
Right Ventricular Dysplasia

3.) Heart Rhythm Disorders, such as Brugada Syndrome, Long QT Syndrome, and Wolff
Parkinson White Syndrome.

4.) Some other common causes of SCA not related to having heart disease are:  
recreational drug use, electrocution, hypothermia, drowning, and commotio cordis
(which is a disruption in the heart rhythm due to a sudden blow to the chest).

Is SCA treatable?  

Yes, it frequently is, and with appropriate treatment, it is possible to greatly increase survival rates.  This is where you come in – you can help treat the leading killer in this country! Right now, the overall survival rate from SCA is only 10.4%. If the SCA is due to the chaotic rhythm of ventricular fibrillation, the survival rate is 31.7%. Survival rates increase significantly in places with strong AED programs and CPR training, such as Las Vegas casinos where survival rates jump to over 70%! Communities with strong CPR training programs and AEDs in police cars, local parks, recreation centers, schools and sporting fields, such as King County, Washington, have survival rates of 62%.

When a bystander witnesses an SCA event and has the confidence to begin CPR and deploy an AED, the victim’s chances of survival are greatly increased. Think of CPR as support – you are supporting the victim because every time you push on the chest, blood flows from the heart up to the brain and out to the vital organs. The AED, on the other hand, is treatment – it stills the chaotic rhythm of the ventricular fibrillation and allows the heart to restore its natural rhythm.

Arm yourself! Take a CPR course which includes AED use, and you will be able to recognize the signs of Sudden Cardiac Arrest and know what steps to take to help a victim of this quick, silent killer. Quality CPR and early defibrillation are crucial!