A heart attack occurs when the flow of blood to the heart is blocked. The blockage is most often a buildup of fat, cholesterol and other. A heart attack, also called a myocardial infarction, happens when a part of the heart muscle doesn't get enough blood. A heart attack (myocardial infarction or MI) is a serious medical emergency in which the supply of blood to the heart is suddenly blocked. Chest discomfort. Most heart attacks involve discomfort in the center of the chest that lasts more than a few minutes – or it may go away and then return. Your heart muscle needs oxygen to survive. A heart attack occurs when the blood flow that brings oxygen to the heart muscle is severely reduced or cut off. A heart attack (often called a myocardial infarction) occurs when the heart muscle doesn't get enough blood. Blood carries oxygen and nutrients to the heart. A heart attack happens when something blocks the blood flow to your heart so it can't get the oxygen it needs. More than a million Americans. Symptoms · About 2 out of every 3 people who have heart attacks have chest pain, shortness of breath or feel tired a few days or weeks before the attack. · A. A heart attack (medically known as a myocardial infarction) is a deadly medical emergency where your heart muscle begins to die because it. 'Dancing With The Devil The Art Of Starting Over': : Watch the Demi Lovato.