SCA (Sudden Cardiac Arrest) is much different than a heart attack in that their root problems that lead to the malfunction are different. Heart attacks occur when there is a blockage in either one or many arteries to the heart, preventing blood and oxygen from reaching the heart.
Sudden Cardiac Arrest is an electrical malfunction leading to an irregularly fast heartbeat. Often times, the blood flow to the brain is reduced leading to a loss of consciousness almost immediately. In short, sudden cardiac arrest can happen during a heart attack but it is not a heart attack.
While there are some symptoms of sudden cardiac arrest, often times it strikes with little or no alert. In fact - with Zachary Schrah, there were no symptoms, there were no warning signs.
If you or someone you know begins to feel dizzy or their heart begins racing and it alerts them—take them immediately to a emergency facility or call 911.
If you or someone you know has had a previous heart attack, coronary artery disease, practices coronary-risking behavior such as smoking, unhealthy eating habits or recreational drug abuse, advise them of the dangers and help grow awareness of sudden cardiac arrest (SCA). It is vital to share this information with your doctor so that you can both assess ways to lower your risk of this potentially-fatal condition.
More information can be found here - http://www.sca-aware.org/blog/scafoundation/sca-and-heart-attack-understanding-the-difference.
