Dilated Cardiomyopathy (DCM)

Updated:Aug 6,2015

Dilated cardiomyopathy (DCM) is the most common type of the disease. It mostly occurs in adults 20 to 60. Men are more likely than women to have this type of cardiomyopathy.

Dilated cardiomyopathy affects the heart's ventricles and atria. These are the lower and upper chambers of the heart, respectively.

The disease often starts in the left ventricle, the heart's main pumping chamber. The heart muscle begins to dilate (stretch and become thinner). This causes the inside of the chamber to enlarge. The problem often spreads to the right ventricle and then to the atria as the disease gets worse.

When the heart chambers dilate, the heart muscle doesn't contract normally. Also, the heart can't pump blood very well. Over time, the heart becomes weaker and heart failure can occur. Common symptoms of heart failure include shortness of breath, fatigue (tiredness), 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. This term is used when overuse of alcohol causes the disease.
  • Congestive cardiomyopathy
  • Diabetic cardiomyopathy
  • Familial dilated cardiomyopathy
  • Idiopathic cardiomyopathy
  • Ischemic cardiomyopathy. This term is used when 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. This term is used 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. As many as one-third of the people who have dilated cardiomyopathy inherit it from their parents.

Certain 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 5 months of birth
  • Certain toxins such as cobalt
  • Certain drugs (such as cocaine and amphetamines) and two medicines used to treat cancer (doxorubicin and daunorubicin)
Other Types of Cardiomyopathy: Also in this section:
Learn more:

Source: National Heart, Lung, and Blood Institute, National Institutes of Health, U.S. Department of Health and Human Services

Cardiomyopathy in Adults

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