Attack (Myocardial Infarction)
What Causes a Heart Attack?
Usually, a heart attack is caused when a plaque abruptly cracks or ruptures. Plaque sometimes abruptly cracks and breaks off from the arterial wall. A blood clot may then rapidly form over the disrupted plaque. This clot can completely clog the coronary artery.
Sometimes a coronary artery contracts in a spasm. This can also narrow the artery, prevent blood flow to part of the heart, and cause a heart attack.