Heart attack means that some of the muscle tissue in your heart is severely injured or has died. The medical term for the death of cardiac muscle is myocardial infarction. Because it is not always possible to determine whether there is only serious injury or there is infarction, the general term for the condition is acute coronary syndrome (ACS).
Most commonly, a heart attack starts with a sensation of heavy pressure or pain in the chest, often extending into the neck or left arm. You may have trouble catching your breath or you may feel weak and break into a cold sweat. Read about what a heart attack feels like on the National Heart, Lung, and Blood Institute web site.
A heart attack usually occurs because one of the blood vessels (called coronary arteries) that bring blood to your heart muscle is blocked. This usually happens when a blood clot forms in a blood vessel that is already partially closed. The partial closure is usually due to atherosclerosis (often called hardening of the arteries). Obstruction occurs gradually over many years as lipid plaques are deposited along the walls of the blood vessels. These plaques narrow and stiffen the arteries and can rupture unexpectedly, totally blocking off the affected artery.
2. If I have chest pain, does that mean I am having a heart attack?
Many other problems can cause chest pain, and it is not possible to tell from the type of chest pain whether or not you are having a heart attack. Many people have chest pain from straining the muscles in their chest, from heartburn or other problems involving the stomach and esophagus, from emotional stress, and with some lung problems. Chest pain that occurs during exercise, hard work, or at times of stress, lasts for a few minutes, and goes away with rest is often caused by angina. A relatively rare form of chest pain may be due to temporary heart spasms called variant angina. These spasms usually occur at night when a person is resting and can cause severe but temporary pain.
If chest pain lasts longer than just a few minutes, especially if it occurs when you are resting, seek immediate medical attention.
3. What if I am not sure if I am having a heart attack?
Many people are not sure if they are experiencing a heart attack. If you are unsure, don't wait, but get help. If you have ongoing pain in the upper body such as the chest, shoulders, arms, neck or jaw or pain in the upper part of your stomach, or if you have been previously diagnosed with angina and the drugs you were prescribed do not ease the pain, seek immediate medical attention. Shortness of breath, nausea, sweating and dizziness are also signs and symptoms. Getting help right away can help you survive and treatments given soon after a heart attack can help limit the damage to your heart.
4. What are high-sensitivity troponin (hs-troponin) tests?
High-sensitivity troponin tests measure the same protein in the blood as the standard test but at much lower levels. Because these new generation of tests are more sensitive than standard ones, they become positive sooner and may help detect acute coronary syndrome earlier. The hs-troponin test may also be positive in people with stable angina and even in people with no symptoms. In these cases, a positive test indicates an increased risk of future heart events such as heart attacks. Hs-troponin is not approved in the U.S. at this time, but research is ongoing and it may become available soon. It is already routinely used in Europe, Canada, and other countries as well.
This article was last reviewed on April 20, 2015. | This article was last modified on July 8, 2015.
The review date indicates when the article was last reviewed from beginning to end to ensure that it reflects the most current science. A review may not require any modifications to the article, so the two dates may not always agree.
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