Dilated/Congestive Cardiomyopathy

Dilated cardiomyopathy, also called congestive cardiomyopathy, is the most common type of cardiomyopathy, representing nearly ninety percent of all cardiomyopathies. The tightly stretched heart muscles and excessive scar tissue characteristic of the disease prevent the heart from pumping efficiently.

 

If the heart does not pump normally, other organs, including the lungs, kidneys and liver, are unable to work effectively. Dilated cardiomyopathy is a last stage disease of other illnesses and, left untreated, can result in congestive heart failure.

Some dilated cardiomyopathies can be treated. These are called reversible dilated cardiomyopathies. For example, some pregnant women get cardiomyopathy as a result of hormonal and circulatory changes. Once the woman's body returns to normal, the cardiomyopathy is generally resolved.

The same is true of vitamin deficiencies like selenium, calcium and phosphate deficiency. In these cases, treating the specific deficiency is often enough to restore normal heart function. Cardiomyopathy resulting from alcohol or cocaine abuse may also be reversed if the disease is not in the late stages.

The treatment used for dilated cardiomyopathy is essentially the same as for heart failure. Drug therapy may include diuretics, anticoagulants and anti-arrhythmics. A low salt diet and elimination of alcohol is recommended for most heart patients. Because smoking can exacerbate symptoms, doctors recommend that smokers quit.

Treating With Diuretics: Most patients with dilated cardiomyopathy develop congestive heart failure. In congestive heart failure, fluid gets backed up in the heart because of the heart's inability to pump it out. Eventually, the backed-up fluid begins to accumulate in other parts of the body like the lungs, liver, and ankles, resulting in edema. Treatment with diuretics ("water pills") is often employed to prevent the body from accumulating too much fluid.

Preventing Blood Clots: Dilated cardiomyopathy also raises the risk of blood clot formation. Blood clots formed in the heart can travel to and become lodged in the brain, increasing the risk of stroke. To prevent blood clots from forming, doctors may prescribe a blood thinner (anticoagulant), such as warfarin.

Avoiding Sudden Death: Strenuous exercise is discouraged in patients with dilated cardiomyopathy because of the increased risk of sudden death. Surgical implantation of a defibrillator, or treatment with anti-arrhythmic agents, may help protect against life-threatening arrhythmias.

The prognosis for patients with dilated cardiomyopathy depends on the progress of the disease and the underlying cause. In general, only thirty to fifty percent of patients live five years after diagnosis. The number drops to 25 percent after ten years. Some patients with extensive disease may be candidates for heart transplants.

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). Dilated cardiomyopathy. MedlinePlus Medical Encyclopedia.