What is heart attack

A heart attack occurs when blood flow to a section of heart muscle becomes blocked. If the flow of blood isn’t restored quickly, the section of heart muscle becomes damaged from lack of oxygen and begins to die.

Heart attack is a leading killer of both men and women in the United States. But fortunately, today there are excellent treatments for heart attack that can save lives and prevent disabilities. Treatment is most effective when started within 1 hour of the beginning of symptoms. If you think you or someone you’re with is having a heart attack, call 9–1–1 right away.

Heart With Muscle Damage and a Blocked Artery

Figure A is an overview of a heart and coronary artery showing damage (dead heart muscle) caused by a heart attack. Figure B is a cross-section of the coronary artery with plaque buildup and a blood clot.

During a heart attack, if the blockage in the coronary artery isn’t treated quickly, the heart muscle will begin to die and be replaced by scar tissue. This heart damage may not be obvious, or it may cause severe or long-lasting problems.