Q. What’s the difference between a heart attack and cardiac arrest?
A. People often confuse sudden cardiac arrest (SCA) with heart attack. While SCA can follow a heart attack, these two heart problems are entirely different.
During a heart attack — also called an acute myocardial infarction — blood is blocked from flowing to the heart. As a result, part of the heart muscle can be damaged or killed. Usually, the blockage is caused by a blood clot formed from the buildup of fatty deposits in the heart’s arteries.
Cardiac arrest, however, is caused by a malfunction in the heart’s electrical system. Often, an abnormal heart rhythm, called an arrhythmia, is to blame. When the heart’s rhythm is disrupted completely, it fails to deliver blood to the brain and other vital organs. Unless the heartbeat is restored within minutes, death occurs. A device that sends an electrical shock to the heart, called a defibrillator, can be used to get the heart beating again.
Q. Are heart attacks and cardiac arrest caused by the same thing?
A. Artery blockage from heart disease is the No. 1 culprit in heart attack and cardiac arrest. When lack of blood flow damages the heart, the resulting scar tissue can wreak havoc on the heart’s electrical system and lead to SCA. In fact, most people who experience cardiac arrest have heart disease and may have unknowingly had a heart attack at an earlier time. Conditions such as high blood pressure, diabetes and obesity also frequently play a role in both heart attack and SCA.
Cardiac arrest can also be caused by severe physical stress from major blood loss, lack of oxygen or low levels of critical minerals like potassium and magnesium; an electrical shock; structural heart abnormalities from inherited disorders; and heart defects or infections.
Q. How can I tell the difference between a heart attack and cardiac arrest?
A. Fainting is usually the first sign of cardiac arrest. Breathing often stops and no pulse is felt. Some report dizziness, a racing heartbeat or lightheadedness before losing consciousness.
Heart attack symptoms are more varied than symptoms of SCA. While chest pain can occur, other signs include:
- Chest tightness or pressure
- Sweating, nausea or vomiting
- Upper body discomfort in the arms, back, neck, jaw or stomach
- Shortness of breath
- And others
Q. What should I do if I see someone with those symptoms?
A. Call 911 immediately. Both cardiac arrest and heart attack are life-threatening conditions. Emergency medical responders can begin providing care en route to the hospital, and help the hospital be better prepared to respond when the patient arrives.
Tanner Heart & Vascular Specialists, a Tanner Medical Group practice, has offices in Bremen, Carrollton, Villa Rica and Wedowee. For more information, call 770-812-9326 or visit HeartAndVascularSpecialists.org.