Dilated Cardiomyopathy

Dilated cardiomyopathy is a common condition in which the normal muscular function of the heart is weakened or enlarged by various causes, and there is some physiologic compensation for this malfunction. The condition causes a decrease in the contractile force of the heart ventricles without any pressure or volume overload. The loss of this cardiac muscle function can result in congestive heart failure.

Causes of dilated cardiomyopathy include: 

  • Exposure to mercury, lead, or catecholamines, hormones secreted by the adrenal glands such as adrenalin, noradrenalin, and dopamine
  • Genetic abnormalities
  • Metabolic disorders
  • Prolonged alcohol use
  • Prolonged rapid heart rate (tachycardia)
  • Thyrotoxicosis, overactivity of the thyroid gland
  • Use of doxorubicin, a drug used to treat some cancers

 Dilated cardiomyopathy is most common in men, although it can affect anyone, including children. Restrictive cardiomyopathy is a less common condition.

Dilated Cardiomyopathy Symptoms

The symptoms are similar to those of heart failure. They usually appear gradually but can appear quickly.

Common symptoms in adults include:

  • Elevated heart rate
  • Enlarged abdominal girth secondary to increased fluid in the abdomen
  • Neck vein distension
  • Shortness of breath on exertion
  • Shortness of breath when lying flat
  • Swelling in the legs caused by fluid
  • Waking up at night with shortness of breath

Children will have these symptoms:

  • Difficulty feeding
  • Pale skin
  • Poor growth
  • Weak pulse in the arms and legs

Diagnosis of Dilated Cardiomyopathy

Dilated cardiomyopathy is often diagnosed during examination for the cause of heart failure. Diagnostic tests include:

  • Cardiac catheterization – to exclude ischemic heart disease
  • Chest X-ray – shows enlarged heart that is greater than 50 percent size of chest wall
  • Echocardiography – evaluates the contractile force of heart chambers
  • Electrocardiogram – shows left ventricle hypertrophy
  • Gated blood pool scanning – to evaluate ejection fraction of the heart chambers
  • Physical exam:
    • Cardiac enlargement
    • Liver enlargement
    • Pulmonary sounds
    • Third and fourth heart sounds by stethoscope

Treatment of Dilated Cardiomyopathy

Treatment focuses on treating heart failure, including:

  • Heart transplantation if all other standard treatments have been unsuccessful and you still have severe symptoms
  • Removal of the offending agent (doxorubicin, toxin, etc.)
  • Supportive therapy:
    • ACE inhibitors – medications that help the heart work better
    • Beta-blockers – medications that lower blood pressure
    • Cardiac glycosides – drugs used to stimulate the heart
    • Diuretics – drugs that reduce fluids in the body
    • Salt restriction in diet
    • Vasodilators – drugs that open the blood vessels and improve blood flow

Request an Appointment

To meet with a cardiac rehabilitation expert at UT Southwestern's facilities in Dallas or for more information about our services, request an appointment or call 214-645-8300.