Myocardial Infarction or Heart Attack

A heart attack, or myocardial infarction, begins when a portion of the heart muscle suddenly loses its blood supply due to an obstruction of the coronary arteries. The obstruction is typically due to coronary arteriosclerosis. If the obstruction persists for more than a few minutes, the affected cardiac muscle tissue will begin to die. This is known as a heart attack. A brief obstruction that resolves itself will cause chest pain (angina pectoris), but often results in minimal or no cardiac muscle damage.

Medications are typically administered within four to six hours of a heart attack to dissolve blood clots and reduce mortality rates. In some cases, interventional heart catheterization is required to restore blood flow. Survival of heart attacks are directly related to the amount of heart tissue affected by the obstruction, the time elapsed before treatment, and the physical condition of the victim and the heart at the time of the heart attack.