A heart attack (also called myocardial infarction or MI) occurs
when an area of heart muscle is completely deprived of blood, and the heart muscle cells die.
A heart attack may result when plaque inside the heart arteries
breaks open or ruptures, forming a clot that significantly blocks blood flow through the artery.
A plaque is made up of cholesterol, white blood cells, calcium,
and other components; it is surrounded by a fibrous cap. If a sudden surge in blood pressure causes the artery to constrict,
the fibrous cap may tear or rupture. This signals the body to repair the injured artery lining, much as it might heal a cut
on the skin, by forming a blood clot to seal the area. A blood clot that forms in an artery can completely block blood flow
to the heart muscle and cause a heart attack.
The pain of a heart attack often occurs with other symptoms,
including:
- Chest discomfort or pain that is crushing or squeezing or feels
like a heavy weight on the chest.
- Chest discomfort or pain that occurs with:
- Sweating.
- Shortness of breath.
- Nausea or vomiting.
- Pain that spreads from the chest to the neck, the jaw, or one
or both shoulders or arms.
- Dizziness or lightheadedness.
- A fast or irregular heartbeat.
- Loss of consciousness.
The pain of a heart attack usually will not go away with rest.
It is important to recognize the early stages of a heart attack
and to seek emergency care. Medical treatment is needed to prevent death. Sometimes medicines can be given to reduce the damage
to the heart muscle caused by a heart attack.