What is Heart Attack?
If you believe that you are having the symptoms of a heart attack, please call 911 immediately and seek medical attention.
The heart is a muscle like any other in the body. Arteries supply it with oxygen-rich blood so that it can contract and push blood to the rest of the body. When there isn't enough oxygen flow to a muscle, its function begins to suffer. Block the oxygen supply completely, and the muscle starts to die.
- Heart muscle gets its blood supply from arteries that originate in the aorta just as it leaves the heart.
- The coronary arteries run along the surface of the heart and supply oxygen-rich blood to the heart muscle.
- The right coronary artery supplies the right ventricle of the heart and the inferior (lower) portion of the left ventricle.
- The left anterior descending coronary artery supplies the majority of the left ventricle, while the circumflex artery supplies the back of the left ventricle.
- The ventricles are the lower chambers of the heart; the right ventricle pumps blood to the lungs and left pumps it to the rest of the body.
What Causes a Heart Attack?
Over time, plaque can build up along the course of an artery and narrow the channel through which blood flows. Plaque is made up of cholesterol buildup and eventually may calcify or harden, with calcium deposits. If the artery becomes too narrow, it cannot supply enough blood to the heart muscle when it becomes stressed. Just like arm muscles that begin to ache or hurt when heavy things are lifted, or legs that ache when you run too fast; the heart muscle will ache if it doesn't get adequate blood supply. This ache or pain is called angina. It is important to know that angina can manifest in many different ways and does not always need to be experienced as chest pain.
If the plaque ruptures, a small blood clot can form within the blood vessel, acting like a dam and acutely blocking the blood flow beyond the clot. When that part of the heart loses its blood supply completely, the muscle dies. This is called a heart attack, or an MI - a myocardial infarction (myo=muscle +cardial=heart; infarction=death due to lack of oxygen).
Picture of Heart Attack (Myocardial Infarction)
Medically Reviewed by a Doctor on 11/20/2017
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