Your heart is the epicenter of your circulatory system. Coronary arteries supply your heart with blood, oxygen and nutrients, allowing the heart to pump blood to the rest of your body. Over time, cholesterol and other fats can build up in your arteries through a process called atherosclerosis. This plaque narrows your blood vessels and can sometimes rupture, forming a clot and blocking the artery. A heart attack occurs when the blockage prevents blood from reaching the heart and parts of the heart muscle begin dying.

The longer your heart goes without blood, the more serious the damage. The lack of blood flow destroys parts of your heart and deprives other organs of necessary nutrients. Heart attacks can cause severe complications, including heart failure and sudden cardiac arrest.