What is a heart attack? — A heart attack, also called myocardial infarction, or MI, is what happens when one of the arteries that supply blood to the heart gets blocked. When this happens, the part of the heart that normally gets blood from that artery is damaged. The longer the time the artery is blocked, the bigger the heart attack. The arteries that supply blood to the heart are called the "coronary arteries."
Heart attacks are usually the result of a condition called "coronary heart disease" or "coronary artery disease." In this disease, fatty deposits called plaques form on the walls of the coronary arteries (figure 1). These plaques sometimes break open and cause blood clots to form. Then the blood clot can block off the artery and keep blood from reaching parts of the heart muscle. That is what causes most heart attacks (figure 2).
What are the symptoms of a heart attack? — People having a heart attack often notice (figure 3):
Pain, pressure, or discomfort in the chest
Pain, tingling, or discomfort in other parts of the upper body, including the arms, back, neck, jaw, or stomach
Shortness of breath
Nausea, vomiting, burping, or heartburn
Sweating or cold, clammy skin
A racing or uneven heartbeat
Feeling dizzy or lightheaded
If you think you might be having a heart attack, call 9-1-1 right away. Do not try to get to the hospital on your own.
Is there a test for heart attacks? — Yes. If your doctor thinks you are having a heart attack, he or she might order one or more of these tests:
An electrocardiogram (ECG) – This test measures the electrical activity in your heart.
Blood tests – During a heart attack, the heart releases certain chemicals. If these chemicals are in your blood, it might mean you are having a heart attack.
Echocardiogram – This test uses sound waves to create an image of your heart as it beats. In a heart attack, not all parts or the heart pump normally.
Cardiac catheterization (also called "cardiac cath") – During this test, the doctor puts a thin tube into a blood vessel in your leg or arm. Then he or she moves the tube up to your heart. Next, the doctor puts a dye that shows up on X-ray into the tube. This part of the test is called "coronary angiography." It can show whether any of the arteries in your heart are clogged.
How is a heart attack treated? — If you go to the hospital while you are having a heart attack, the doctors and nurses will do a few things:
They might give you oxygen through a mask or a tube in your nose.
They will give you pain medicines to ease the chest pain and discomfort of a heart attack. They might also give you something to help you relax.
They will give you medicines to help keep more blood clots from forming.
They might give you a medicine called a beta blocker to reduce your heart's need for oxygen. This medicine can help reduce the damage caused by a heart attack.
They will try to get blood flowing again through the clogged artery. Doctors can do this in 1 of 2 ways:
•They can give you medicines through a thin tube that goes into a vein, called an "IV," to break up clots. These have been called "clot busters."
•They can do a procedure called "stenting" combination with cardiac catheterization. This involves putting a tiny metal tube called a "stent" into the blocked artery to hold it open.
If you cannot get a stent, or if the stent does not work, your doctor might suggest open heart surgery. This is also called "coronary artery bypass grafting" or "bypass surgery" (figure 4). During this surgery, doctors create a new path – a detour – for blood to get around the clogged portion of the artery. They do this using a combination of your own arteries and veins.
You will likely stay in the hospital for 3 to 5 days, unless your heart attack led to other problems that need treatment.
What happens after a heart attack? — After you've had a heart attack, you will probably need to:
Take more medicines than before. It is very important that you take all your medicines every day, as directed. The medicines given to people who have had a heart attack can help prevent other heart attacks, and they reduce the chances of having a stroke or dying. If you can't afford your medicines, or if the medicines give you side effects, mention it to your doctor. There are often ways to solve these problems.
Improve the way you eat. Try to avoid fried foods and too many foods with sugar. Eat lots of fruits and vegetables. Try to eat foods that have fiber in them.
Lose weight, if you are overweight. Losing extra weight reduces the chance of another heart attack and can make you feel better.
Become more active. Walking, gardening, or any activity that gets you to move more can help reduce the risk.
All topics are updated as new evidence becomes available and our peer review process is complete.
This topic retrieved from UpToDate on: Mar 30, 2020.
Topic 15786 Version 18.0
Release: 28.2.2 - C28.105
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