Tests and diagnosisBy Mayo Clinic staff
Your doctor will conduct a physical examination, take a personal and family medical history, and ask when your symptoms occur — for example, whether exercise brings on your symptoms. If your doctor thinks you have cardiomyopathy, you may need to undergo several tests to confirm the diagnosis. These tests may include:
- Chest X-ray. An image of your heart will show whether it's enlarged.
- Echocardiogram. An echocardiogram uses sound waves to produce images of the heart. Your doctor can use these images to examine the size and function of your heart and its motions as it beats. This test checks your heart valves and helps your doctor determine the cause of your symptoms.
- Electrocardiogram (ECG). In this noninvasive test, electrode patches are attached to your skin to measure electrical impulses from your heart. An ECG can show disturbances in the electrical activity of your heart, which can detect abnormal heart rhythms and areas of injury.
- Cardiac catheterization and biopsy. In this procedure, a thin tube (catheter) is inserted in your groin and threaded through your blood vessels to your heart, where a small sample (biopsy) of your heart can be extracted for analysis in the laboratory. Pressure within the chambers of your heart can be measured to see how forcefully blood pumps through your heart. Pictures of the arteries of the heart can be taken during the procedure (coronary angiogram) to ensure that you do not have any blockage.
- Cardiac magnetic resonance imaging (MRI). Cardiac MRI is an imaging technique that uses magnetic fields and radio waves to create images of your heart. Cardiac MRI is often used in addition to echocardiography, particularly if the images from your echocardiogram aren't helpful in making a diagnosis.
- Blood tests. One blood test can measure B-type natriuretic peptide (BNP), a protein produced in your heart. Your blood level of BNP rises when your heart is subjected to the stress of heart failure, a common complication of cardiomyopathy.
A variety of other blood tests may be done, including those to check your kidney function and look for anemia and thyroid problems. Your iron level may be measured. Having too much may indicate an iron overload disorder called hemochromatosis. Accumulating too much iron in your heart muscle can weaken it and cause cardiomyopathy.
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