by Kimberly Allen, RN
Sudden cardiac arrest occurs when there is a short circuit in the electrical system of the heart causing an unexpected and sudden loss of heart function as well as respiration’s and consciousness. Sudden cardiac arrest is not a heart attack. Hear attacks occur because of a blockage of some type preventing blood flow to the heart muscle. In the Us approximately 325,000 adult deaths are due to sudden cardiac arrest every year. Sudden cardiac arrest is responsible for at least half of all deaths due to heart disease. However, it’s the occasions when a young athlete suffers from sudden cardiac arrest that people take notice. The Cleveland Clinic estimates that up to 1 in every 300,000 deaths in athletes under 35 years of age is due to sudden cardiac arrest. Males are three times more likely to suffer from sudden cardiac arrest than women.
To understand sudden cardiac arrest you need to remember the heart is basically an electric pump. In someone that suffers a sudden cardiac arrest there is an electrical malfunction in the heart. While other muscles in our body have nerve connections that they receive the electrical signals that tells them what to do the heart has it’s own independent electrical system.. The hearts electrical system centers on what’s called the “sinus node”. It is the sinus node that produces the electrical signals that regulate the contraction and relaxation of the heart muscle in a synchronized rhythm. When something occurs to cause the sinus node to malfunction the electrical signals that regulate the hearts ability to pump basically short circuit. When the electrical system short circuits the heart starts pumping the blood at a dangerous rate. This dangerous pace causes the ventricles of the heart to flutter and lose it’s ability to pump in a forceful coordinated beat. When this occurs it’s called ventricular fibrillation or “V-fib”. a person that suffers a sudden cardiac arrest will suddenly collapse with a loss of consciousness and have no pulse and not breathing.
The majority of cases of sudden cardiac arrest are due to coronary artery disease. When the arteries become clogged it reduces blood flow which makes it more difficult for the heart to transmit the electrical signals efficiently. Heart attacks can also lead to sudden cardiac arrest. Heart attacks not only trigger ventricular fibrillation followed by sudden cardiac arrest heart attacks can cause areas of scar tissue to form in the heart muscle which can cause the electrical signals to short circuit causing an abnormal heart rhythm. However, in young people sudden cardiac arrest is usually caused by an uncommon disorder. When sudden cardiac arrest occurs in a young person there is usually some type of congenital heart disease or diseases of the heart muscle or electrical system that are inherited. The most common of these is called hypertrophic cardiomyopathy or HCM.
In HCM the heart muscle is thicker than normal. This can lead to the inner layers of heart muscle not getting enough blood supply. Other congenital abnormalities including those involving the coronary arteries as well as the valves can lead to sudden cardiac arrest. Marfan syndrome is a genetic disorder that involves the connective tissue. This can lead to deformities in blood vessels especially the aorta which in turn can lead to sudden increases in blood pressure during times of intense activity such as playing sports.
In the past it was rare for a person that suffered a sudden cardiac arrest to survive. However, with today’s technology more and more are surviving. The only treatment for sudden cardiac arrest is CPR and defibrillator. Fortunately technology has improved to a point that defibrillators can be found almost anywhere. They are not just for the hospital anymore. Portable defibrillators can be found in schools, at sporting events and on school buses to name a few.
Some states and schools require all student athletes be screened for the risk of sudden cardiac arrest which includes and electrocardiogram and if an abnormal rhythm is noted the doctor will recommend further testing.
Kimberly Allen is a registered nurse with an AND in nursing. She has worked in ACF, LCF and psychiatric facilities, although she spent most of her career as a home health expert. She is now a regular contributor to HealthAndFitnessTalk.com, dispensing advice and knowledge about medical issues and questions. You can reach her with any comments or questions at firstname.lastname@example.org.