Dilated Cardiomyopathy (DCM)

Dilated cardiomyopathy (DCM) is the most common type, occurring mostly in adults younger than 50. It affects the heart's ventricles and atria, the lower and upper chambers of the heart.

Frequently, the disease starts in the left ventricle, the heart's main pumping chamber. The heart muscle begins to dilate, stretching and becoming thinner. As a result, the inside of the chamber enlarges. The problem often spreads to the right ventricle and then to the atria.

As the heart chambers dilate, the heart muscle doesn't contract normally and can't pump blood very well. As the heart becomes weaker, heart failure can occur. Common symptoms of heart failure include shortness of breath, fatigue and swelling of the ankles, feet, legs, abdomen and veins in the neck.

Dilated cardiomyopathy also can lead to heart valve problems, arrhythmias (irregular heartbeats) and blood clots in the heart.

Other Names for Dilated Cardiomyopathy

  • Alcoholic cardiomyopathy. (Overuse of alcohol causes the disease)
  • Congestive cardiomyopathy
  • Diabetic cardiomyopathy
  • Familial dilated cardiomyopathy
  • Idiopathic cardiomyopathy
  • Ischemic cardiomyopathy (Coronary heart disease, also called coronary artery disease, or heart attack cause the disease. Not all forms of DCM are ischemic in origin.)
  • Peripartum cardiomyopathy (When the disease develops in a woman shortly before or after she gives birth)
  • Primary cardiomyopathy

What Causes Dilated Cardiomyopathy

The cause of dilated cardiomyopathy often isn't known. Up to one-third of the people who have it inherit it from their parents.

Some diseases, conditions and substances also can cause the disease, such as:

  • Coronary heart disease, heart attack, high blood pressure, diabetes, thyroid disease, viral hepatitis and HIV
  • Infections, especially viral infections that inflame the heart muscle
  • Alcohol, especially if you also have a poor diet
  • Complications during the last month of pregnancy or within five months of birth
  • Certain toxins such as cobalt
  • Certain drugs (such as cocaine and methamphetamines) and two medicines that treat cancer (doxorubicin and daunorubicin)