Dilated cardiomyopathy is a condition in which the heart becomes weakened and enlarged, and cannot pump blood efficiently. The decreased heart function can affect the lungs, liver, and other body systems.

There are several different types of cardiomyopathy. Dilated cardiomyopathy is the most common form.

See also:

• Alcoholic cardiomyopathy
• Hypertrophic cardiomyopathy
• Ischemic cardiomyopathy
• Peripartum cardiomyopathy
• Restrictive cardiomyopathy

There are many causes of dilated cardiomyopathy. Some of these are:

• Alcoholism (alcoholic cardiomyopathy)
• Anemia
• Coronary artery disease
• Nutritional deficiencies
• Valvular heart disease
• Stress
• Viral infections (rare)

The most common causes of dilated cardiomyopathy in children are:

• Heart (coronary) disease
• Myocarditis
• Some infections
• Unknown cause (idiopathic dilated cardiomyopathy)

This condition can affect anyone of any age, although it is most common in adult men.

Risk factors in adults include:

• Alcoholism
• Cocaine use
• Family or personal history of cardiac disorders (such as myocarditis)
• Obesity

• Alström syndrome
• Bulging neck veins
• Cough
• Decreased alertness or concentration
• Failure to thrive (in children)
• Fatigue, weakness, faintness
• Heart failure
• Loss of appetite
• Low urine production
• Need to urinate at night (in adults)
• Pulse may feel irregular or rapid
• Sensation of feeling the heart beat (palpitations)
• Shock
• Shortness of breath, especially with activity
• Shortness of breath occurring after lying down for awhile, or in infants while feeding
• Swelling of feet and ankles (in adults)
• Swelling of the abdomen (in adults)

Note: Symptoms of heart failure often develop gradually. Some chest pain may also be associated with this disease.

Cardiomyopathy is usually discovered when the doctor is examining and testing you for the cause of heart failure. Tapping over the heart with the fingers and feeling the area may indicate that the heart is enlarged. Listening to the chest with a stethoscope reveals lung crackles, heart murmur, or other abnormal sounds. The liver may be enlarged. Neck veins may be bulging.

Children will have poor growth, pale skin, difficulty feeding, and weak pulses in the legs and arms.

Heart enlargement, congestion of the lungs, decreased movement/functioning of the heart, or heart failure may show on these tests:

• Cardiac catheterization and coronary angiography
• Chest CT scan or MRI of the heart
• Chest x-ray
• Echocardiogram
• Nuclear heart scan (MUGA, RNV)

An ECG may show conduction disturbances or arrhythmias, including tachycardia, and may indicate enlargement of the ventricles. Heart biopsy may be helpful to distinguish dilated cardiomyopathy from other diseases. Lab tests vary depending on the suspected cause.

The person may need to stay in the hospital until acute symptoms start to go away. Treatment is focused on relief of symptoms. Drugs and treatments that may be used include:

• ACE-inhibitors
• Digitalis
• Diuretics (water pills)
• Nutritional supplements
• Other medications to reduce symptoms
• Vasodilators (drugs that dilate blood vessels)

The underlying cause should be treated. Some people may require a biventricular pacemaker. An implantable defibrillator may also be needed to correct or prevent any severe arrhythmias (abnormal heart rhythms). A biventricular pacemaker that also functions as a defibrillator is available.

A low-salt diet may be prescribed for adults, and fluid may be restricted in some cases. The person can usually continue their regular activities, if they are able.

The person may be asked to monitor his or her body weight daily. Weight gain of 3 pounds or more over 1 or 2 days may indicate fluid accumulation (in adults).

Smoking and drinking alcohol may worsen the symptoms.

If the heart function remains poor, a heart transplant may be considered.

The outcome varies. Some people will remain in a stable condition for long periods, some continue to get gradually sicker, and others quickly get worse. Cardiomyopathy can be corrected only if the underlying disease can be cured.

In children, about one-third recover completely, one-third recover but continue to have some heart problems, and one-third die.

• Arrhythmias
• Congestive heart failure
• Pulmonary edema
• Side effects of medications, including:
  • Headache
  • Gastrointestinal upset
  • Lightheadedness and fainting
  • Low blood pressure
  • Lupus reaction (a group of symptoms including a skin rash and arthritis)

Call your health care provider if you have symptoms of cardiomyopathy.

If chest pain, palpitations, or faintness develop seek emergency medical treatment immediately.

Eat a well-balanced and nutritious diet, exercise to improve heart fitness, stop smoking, and minimize alcohol consumption.

Hare JM. The dilated, restrictive, and infiltrative cardiomyopathies. Zipes DP, Libby P, Bonow RO, Braunwald E, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 8th ed. Philadelphia, Pa: Saunders Elsevier; 2007: chap 64.