An enzyme test is a blood test that measures certain enzyme levels to assess how well the body’s systems are functioning and whether any tissue damage has occurred. Liver enzyme tests are used to diagnose and monitor the extent of liver diseases or disorders. Cardiac enzyme tests are used to diagnose a heart attack and determine the extent of damage to the heart muscle.

An enzyme test will likely be performed in a physician’s office. During the test, blood is drawn from a vein or capillary in the heel, finger, toe, earlobe, back of the hand or inside the elbow. Enzyme tests typically do not cause much pain for the patient, although a stinging sensation may be felt when the needle is inserted. After the blood is collected, the needle is withdrawn and a small cotton ball or pad is applied with light pressure over the puncture site.

The sample obtained during the test is sent to a laboratory for analysis. Once the results come in, the physician will discuss them with the patient. Appropriate treatment will then follow if necessary.

There are three factors that may interfere with the enzyme test results: vigorous exercise, certain medications and (in some cases) eating before the test. Patients are strongly encouraged to follow their physician’s orders in order to maximize the accuracy of their test results.