Restrictive Cardiomyopathy

Restrictive cardiomyopathy is rare in the United States and most other industrial nations. In this disease, the walls of the ventricles stiffen and lose their flexibility due to infiltration by abnormal tissue. As a result, the heart cannot fill adequately with blood and eventually loses its ability to pump properly.

Restrictive cardiomyopathy typically results from another disease, which occurs elsewhere in the body. In the United States, restrictive cardiomyopathy is most commonly related to the following: amyloidosis, in which abnormal protein fibers (amyloid) accumulate in the heart's muscle; sarcoidosis, an inflammatory disease that causes the formation of small lumps in organs; and hemochromatosis, an iron overload of the body, usually due to a genetic disease.

In general, restrictive cardiomyopathy does not appear to be inherited; however, some of the diseases that lead to the condition are genetically transmitted.

Symptoms

Typical signs of the condition include symptoms of congestive heart failure: weakness, fatigue, and breathlessness. Swelling of the legs, caused by fluid retention, occurs in a significant number of patients. Other symptoms include nausea, bloating, and poor appetite, probably because of the retention of fluid around the liver, stomach, and intestines.

Diagnosis

A physician may suspect restrictive cardiomyopathy based on a patient's symptoms and the presence of another disease. Although symptoms of congestive heart failure may predominate, the size of the heart remains relatively small, unlike other cardiomyopathies.

Diagnostic information comes from an electrocardiogram or any of several imaging studies that provide pictures of the heart. These include echocardiography (EKG), magnetic resonance imaging (MRI), and computed tomography (CT).

A definite diagnosis usually requires cardiac catheterization studies or a biopsy, in which a tiny piece of tissue -- including heart muscle -- is removed for laboratory analysis.

Treatment

Restrictive cardiomyopathy has no specific treatment. The underlying disease that leads to the heart problem also may not be treatable.

In general, the use of traditional heart drugs has been limited in this cardiomyopathy, although diuretics may help control fluid accumulation.

In rare cases, surgery is sometimes used to try to improve blood flow into the heart.

Course of the disease

The condition is similar to dilated cardiomyopathy and tends to worsen with time. Only about 30 percent of patients survive more than 5 years after diagnosis.

Each year, Medical College of Wisconsin physicians care for more than 180,000 patients, representing nearly 500,000 patient visits. Medical College physicians practice at Children's Hospital of Wisconsin, Froedtert Memorial Lutheran Hospital, the Milwaukee VA Medical Center, and many other hospitals and clinics in Milwaukee and southeastern Wisconsin.