Restrictive Cardiomyopathy - Exams and Tests

Exams and Tests

If restrictive cardiomyopathy is identified correctly and right away, symptoms can be treated more successfully.¹ To diagnose restrictive cardiomyopathy, your health professional will ask about your medical history. Be prepared to discuss any conditions or diseases that you or your family members have had. In addition, you should be able to describe your symptoms and how often you experience them.

Your health professional will also do a thorough physical examination, including listening to your heart and lungs with a stethoscope. Signs of heart failure can include:

• Unusual sounds, heart murmurs, or extra sounds called gallops, which may mean you have a problem with the heart's walls or valves. Pulmonary rales—crackles or bubbling sounds heard in the chest—may mean there is fluid buildup in the lungs.
• Fluid buildup (edema), especially in the legs and feet.
• Bulging neck veins.

It is important to remember that people of all ages can develop restrictive cardiomyopathy. When symptoms of cardiomyopathy first develop, several tests can help your doctor diagnose whether an underlying condition, such as sarcoidosis (the formation of nodules) or hemochromatosis (a buildup of iron in the heart muscle), is causing symptoms.

Echocardiogram: An echocardiogram, sometimes called an echo, is an ultrasound exam that uses high-pitched sound waves to create an image of the heart on a television screen. This painless and noninvasive test—which determines if your lower heart chambers (ventricles) are filling too rapidly, a specific sign of restrictive cardiomyopathy—is the easiest way to diagnose restrictive cardiomyopathy.

Electrocardiogram: An electrocardiogram (ECG, EKG) records the electrical activity in the heart as impulses move through it during contraction and relaxation. An electrocardiogram can determine whether heart muscle is damaged and may also suggest other possible causes of cardiomyopathy, such as a heart attack or a buildup of protein in the heart muscle (cardiac amyloidosis).

Chest X-ray: A chest X-ray shows the size and shape of the heart and whether there is fluid buildup in the lungs. In a heart affected by restrictive cardiomyopathy, the upper heart chambers (atria) may sometimes appear enlarged, although usually the overall heart size is normal or only slightly enlarged.

Imaging tests: More complex tests, called magnetic resonance imaging (MRI) and computed tomography (CT), may be used to evaluate restrictive cardiomyopathy. The major benefit of these tests is that they can help distinguish between restrictive cardiomyopathy and constrictive pericarditis. If the sac around the heart (pericardium) is thickened, the symptoms are more likely due to constrictive pericarditis than to restrictive cardiomyopathy.

Cardiac catheterization or coronary angiogram: During cardiac catheterization, a thin, flexible tube called a catheter is threaded through an artery or vein in the arm or groin and into the blood vessels of the heart to measure pressure in the heart chambers. In restrictive cardiomyopathy, there is typically a higher-than-normal pressure inside the heart chambers. Dye can also be injected through the catheter to see how the heart chambers are pumping and whether heart valves are leaking. The process of injecting dye into the coronary arteries is called coronary angiography. Cardiac catheterization may help determine whether you have constrictive pericarditis or restrictive cardiomyopathy.

Other procedures: Sometimes a sample (biopsy) of the heart tissue—usually done during cardiac catheterization—or the pericardium is the only way to determine the cause of restrictive cardiomyopathy (for example, whether it is caused by hemochromatosis or sarcoidosis).