Some blood tests, called cardiac enzymes, can check whether the heart muscle is damaged, and indicate if a person has had a heart attack.
Types of cardiac enzyme tests
The most common test is troponin. Other tests include CK (creatine kinase), CK-MB and myoglobin. These are not specific to the heart muscle and are usually used alongside troponin, or when troponin is not available.
What is being tested?
These tests measure proteins or enzymes found in the heart muscle – they are often called cardiac biomarkers. When the heart muscle is injured, they are released into the bloodstream and the levels that can be detected using blood tests go up. This can happen during and after a heart attack.
The troponin test is most commonly used and is the recommended test to check for heart muscle damage.
Why would I need this test?
You could need this type of test if your doctor suspects that you might be having, or have had, a heart attack or other kinds of damage to your heart muscle. This test might be done if there is an abnormality on a heart tracing (electrocardiogram or ECG) that suggests heart attack or heart muscle damage.
How to prepare for this test
No preparation is needed for this test.
Understanding your results
You should discuss the results with your doctor to understand what they mean specifically for you.
A high level of cardiac enzymes might indicate a heart attack, but your signs and symptoms, and what your ECG shows, are also necessary for a firm diagnosis.
About cardiac enzymes tests
About blood testing
Visit our ‘Guide to blood testing’ to learn more about blood tests in general with information such as:
- what to consider before having the test
- what happens during a blood test
- results accuracy
- blood tests cost.
Last reviewed: August 2016