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Most heart attacks are caused by a blood clot that blocks one of the coronary arteries. The coronary arteries bring blood and oxygen to the heart. If the blood flow is blocked, the heart is starved of oxygen and heart cells die.
The medical term for this is myocardial infarction.
Myocardial infarction; MI; Acute MI; ST - elevation myocardial infarction; Non-ST - elevation myocardial infarction; NSTEMI; CAD - heart attack; Coronary artery disease - heart attack
A substance called plaque can build up in the walls of your coronary arteries. This plaque is made up of cholesterol and other cells.
A heart attack may occur when:
In either case, there is not enough blood flow to the heart muscle and heart muscle dies.
The cause of heart attack is not always known.
Heart attack may occur:
Many risk factors may lead to the development of plaque buildup and a heart attack.
A heart attack is a medical emergency. If you have symptoms of a heart attack, call 911 or your local emergency number right away.
Chest pain is the most common symptom of a heart attack.
The pain can be severe or mild. It can feel like:
The pain most often lasts longer than 20 minutes. Rest and a medicine to relax the blood vessels (called nitroglycerin) may not completely relieve the pain of a heart attack. Symptoms may also go away and come back.
Other symptoms of a heart attack can include:
Some people (the older adults, people with diabetes, and women) may have little or no chest pain. Or, they may have unusual symptoms such as shortness of breath, fatigue, and weakness. A "silent heart attack" is a heart attack with no symptoms.
A health care provider will perform a physical exam and listen to your chest using a stethoscope.
You will have an electrocardiogram (ECG) to look for heart damage. Most of the time, certain changes on the ECG indicate you are having a heart attack. Sometimes these changes are not present, even though other tests indicate you have had a heart attack. This can be called non-ST elevation myocardial infarction (NSTEMI).
A blood test can show if you have heart tissue damage. This test can confirm that you are having a heart attack. You will likely have this test 3 times over the first 6 to 12 hours.
Coronary angiography may be done right away or when you are more stable.
Other tests to look at your heart that may be done while you are in the hospital:
Angioplasty is a procedure to open narrowed or blocked blood vessels that supply blood to the heart.
You may be given drugs to break up the clot. This is called thrombolytic therapy. It is best if these drugs are given soon after the onset of symptoms, usually no later than 12 hours after it and ideally within 30 minutes of arriving to the hospital.
Some people may also have heart bypass surgery to open narrowed or blocked blood vessels that supply blood to the heart. This procedure is also called coronary artery bypass grafting and/or open heart surgery.
TREATMENT AFTER A HEART ATTACK
After several days, you will be discharged from the hospital.
You will likely need to take medicines, some for the rest of your life. Always talk to your provider before stopping or changing how you take any medicines. Stopping certain medicines can be deadly.
While under the care of your health care team, you will learn:
Strong emotions are common after a heart attack.
All of these feelings are normal. They go away for most people after 2 or 3 weeks.
You may also feel tired when you leave the hospital to go home.
Most people who have had a heart attack take part in a cardiac rehabilitation program.
Many people benefit from taking part in support groups for people with heart disease.
After a heart attack, you have a higher chance of having another heart attack.
How well you do after a heart attack depends on several factors such as:
If your heart can no longer pump blood out to your body as well as it used to, you may develop heart failure. Abnormal heart rhythms can occur, and they can be life threatening.
Most people can slowly go back to normal activities after a heart attack. This includes sexual activity. Talk to your provider about how much activity is good for you.
Amsterdam EA, Wenger NK, Brindis RG, et al. 2014 AHA/ACC guideline for the management of patients with non-ST-elevation acute coronary syndromes: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. J Am Coll Cardiol. 2014;64(24):e139-e228. PMID: 25260718 www.ncbi.nlm.nih.gov/pubmed/25260718.
Anderson JL. ST segment elevation acute myocardial infarction and complications of myocardial infarction. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 25th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 73.
O'Gara PT, Kushner FG, Ascheim DD, et al. 2013 ACCF/AHA guideline for the management of ST-elevation myocardial infarction: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. J Am Coll Cardiol. 2013;61(4):485-510. PMID: 23256913 www.ncbi.nlm.nih.gov/pubmed/23256913.
Scirica BM, Morrow DA. ST-elevation myocardial infarction. In: Mann DL, Zipes DP, Libby P, Bonow RO, Braunwald E, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 10th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 51.