Restrictive Cardiomyopathy: A Secondary Cardiovascular Disease

Restrictive cardiomyopathy is the least common cardiomyopathy in the US. Unlike other cardiomyopathies, restrictive cardiomyopathy is characterized by a stiff heart muscle, which prevents the chambers in the heart from filling and emptying properly.

Restrictive cardiomyopathy is rare and usually a complication of another underlying disease. Examples of these diseases are amyloidosis, hemochromatosis and sarcoidosis.

Amyloidosis: The most common form of amyloidosis results from a disorder of plasma cells. In amyloidosis, abnormal protein fibers known as amyloids build up in the body and become trapped in various organs. If the amyloids accumulate in the heart muscle, it can become stiff and is then unable to pump effectively. This results in restrictive cardiomyopathy. Amyloidosis is rare, can be hereditary and has a higher incidence in males.

Hemochromatosis: Hemochromatosis is a common genetic liver disease in the US. However, only the worst cases result in restrictive cardiomyopathy. Increased levels of iron in the blood cause a disease that, left untreated, can develop into restrictive cardiomyopathy.

Sarcoidosis: Sarcoidosis is an inflammatory disease in which immune system cells accumulate in various organs and lead to scarring. If a growth of cells develops in the heart, restrictive cardiomyopathy can develop. Sarcoidosis is most common in African American women between twenty and forty years old but also has a high incidence in countries like Scandinavia, Germany, Ireland and Puerto Rico. Because the cause of sarcoidosis is still unknown, it is hard to determine why certain ethnicities are at higher risk then others.

 

Treatment options are limited for restrictive cardiomyopathy. Lifestyle changes such as decreasing or eliminating strenuous exercise and making dietary changes are recommended. Some of the drugs used to treat other cardiomyopathies like diuretics and anti-arrhythmic drugs can help, but they must be monitored carefully since they can have life-threatening side effects for the patient with restrictive cardiomyopathy. A heart transplant may be the treatment of choice for individuals whose symptoms are not relieved with medications.

According to the American Heart Association, most restrictive cardiomyopathy patients live up to nine years after the diagnosis.

Resources

American Heart Association (updated 2004). Cardiomyopathy.

Beers, M.H. & Berkow, R. (ed). Cardiomyopathy. The Merck Manual of Diagnosis and Therapy, 17th Edition. Merck Research Laboratories, NJ, 1999.

Fauci, A., Braunwald, E., Isselbacher, K., Wilson, J., Martin, J., Kasper, D., Hauser, S. & Longo, D. (ed). Harrison's Principles of Internal Medicine, 14th Edition. McGraw-Hill, New York, 1998.

National Library of Medicine. (updated 2004). Restrictive cardiomyopathy. MedlinePlus Medical Encyclopedia.