What happens during a heart attack?

Marty Denny, MD
Cardiology (Cardiovascular Disease)
During a heart attack, your heart, which is the muscle that pumps the blood to the rest of your body, has a decrease in blood and oxygen supply. Most of the time, this is secondary to a blockage in the heart arteries. It can also be because of a spasm of the artery, which is clenching of the artery, or just a spontaneous blood clot forming. When this occurs, the heart does not get enough oxygen. If this continues for a prolonged period of time -- 20 minutes or greater -- some of the cells of the heart will start to die. When this happens, that is when you have a heart attack. A heart attack is diagnosed by elevation of what are called cardiac enzymes; if your cardiac enzymes are not elevated, you technically did not have a heart attack.
Other causes of heart attacks can be from illicit drug use, low blood count or anemia and excessive exercise with not enough hemoglobin or blood in your system.
Syed W. Bokhari, MD
Cardiology (Cardiovascular Disease)
During a heart attack, the coronary artery gets completely blocked. In this video, Syed Bokhari, MD, an interventional cardiologist at Riverside Community Hospital, describes how the body handles a narrowed artery and how this blocks blood flow. 
Intermountain Healthcare
Normally, the heart receives an adequate blood supply through the coronary arteries. However, during a heart attack, blood flow through a coronary artery is blocked or severely limited for a period of time. This means the muscle doesn't get enough oxygen and blood, and the result can be permanent damage to a portion of your heart. The size and location of your heart muscle damage depends on which coronary artery or branch is blocked.
A heart attack occurs when the blood flow to your heart is either temporarily or permanently stopped, causing pain. Heart muscles require constant blood flow, so any decrease will cause the death of heart muscles. Interruption in blood flow is typically caused by a clot such as one that comes from high cholesterol. Lowering high cholesterol through diet, exercise and medication is the best way to prevent heart attacks.
Dr. Mehmet Oz, MD
Cardiology (Cardiovascular Disease)
A heart attack occurs if blood flow to the heart is blocked. Learn more about this topic in this video.

Randolph P. Martin, MD
Cardiology (Cardiovascular Disease)
Heart attacks occur when plaque, resulting from cholesterol, cause your body to build clots on the inside of your blood vessels. This build up of plaque and clots starves your heart muscle of oxygen and nutrients necessary for its proper function. Watch this video to learn more from Dr. Randy P. Martin about what happens during a heart attack.
Eastside Medical Center
Your heart becomes weak and may stop. This is usually because the blood supply to the heart muscle is blocked or the electrical rhythm is altered. This makes the muscle not squeeze normally and makes the rest of the body run out of blood supply. The new therapies are aimed at restoring the proper electrical rhythm and helping restore the blood flow to the heart so that the muscle can perform its normal function.

Continue Learning about Heart Attack

Heart Attack

Heart Attack

Heart attack (myocardial infarction (MI), is the leading cause of death among Americans. It often results from coronary artery disease, the most common form of heart disease to affect adults. See your doctor immediately if you fee...

l pressure or a squeezing sensation in your chest, neck, jaw, shoulders, back or arms, especially if it’s accompanied by sweating, nausea, vomiting, or shortness of breath.

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.