What is restrictive cardiomyopathy?

Restrictive cardiomyopathy is a serious problem that makes your heart muscle stiff. When your heart muscle is stiff, it can't stretch to allow enough blood to enter its lower chambers, the ventricles. So blood that would normally enter the heart backs up in your circulatory system.

Most of the time, this leads to heart failure. Heart failure does not mean that your heart stops pumping. It means that your heart can't pump enough blood to meet your body's needs.

What causes restrictive cardiomyopathy?

Often the cause is never found. But we do know that there are a number of diseases or problems that can lead to restrictive cardiomyopathy. These include:

• Cardiac amyloidosis, a buildup of an abnormal protein in the heart muscle.
• Hemochromatosis, a buildup of iron in the heart muscle.
• Sarcoidosis, a rare type of heart inflammation.
• Radiation therapy and chemotherapy, used to treat cancer.
• Carcinoid syndrome, a rare disease that causes certain chemicals to be released into the blood stream. These chemicals can stiffen heart muscle.
• Löeffler’s syndrome and endomyocardial fibrosis, conditions that can cause scar tissue in the heart.
• Genetic factors. You can inherit diseases, including Gaucher disease and Fabry's disease, that can lead to restrictive cardiomyopathy. But these diseases can be treated to prevent restrictive cardiomyopathy.

What are the symptoms?

You may not have any symptoms at first. Or you may have mild symptoms, such as feeling very tired or weak.

If your heart gets weaker, you will develop heart failure. When this happens, you will feel other symptoms, including:

• Shortness of breath, especially with activity.
• Tiredness.
• Trouble breathing when you lie down.
• Swelling in your legs.
• Chest pain.

Heart failure that suddenly gets worse is an emergency. Get medical help right away if you:

• Have severe shortness of breath.
• Have a fast or uneven heartbeat.
• Cough up foamy, pink mucus.
• Have chest pain.

How is restrictive cardiomyopathy diagnosed?

Your doctor will ask questions about your symptoms and past health. He or she will want to know about recent illnesses and about heart disease in your family. Your doctor will listen to your heart and lungs and check your legs for fluid buildup.

You may also have other tests, including:

• Electrocardiogram, also known as an ECG or EKG.
• Chest X-ray.
• Echocardiogram.
• Routine blood tests.

In some cases, a doctor may want to look at a small sample of heart tissue, called a biopsy, to make a definite diagnosis.

How is it treated?

You will probably need to take several medicines to treat heart failure caused by restrictive cardiomyopathy. It is very important to take your medicines exactly as your doctor tells you to and to keep taking them. If you don't, your heart failure could get worse.