Basic Facts

  • Doctors use the term cardiomyopathy to describe a chronic disorder of the heart muscle’s function that reduces the ability of the heart to effectively pump blood.
  • Although there are several types of cardiomyopathy, the most common form is dilated cardiomyopathy 
  • A weakened heart responds to a reduced output of blood by dilating, or enlarging, to hold more blood.

Cardiomyopathy is a family of diseases that all make it difficult for the heart to pump blood properly. There are different kinds of cardiomyopathy.

Dilated cardiomyopathy is a chronic disorder that occurs when the main pumping chamber of the heart (the left ventricle) dilates, meaning it stretches. Consequently, the inside of the chamber becomes larger. The heart no longer contracts normally and cannot pump blood very well. As the heart becomes weaker, heart failure can occur. 

Dilated cardiomyopathy is a common cause of congestive heart failure, the name for a range of symptoms that accompany a weakened heart.

Restrictive cardiomyopathy occurs when the heart muscle becomes stiff and not able to fill with blood properly. It is the least common type of cardiomyopathy in the U.S.

Ischemic cardiomyopathy is caused by coronary artery disease and heart attacks. The heart muscle becomes damaged due to blockages in the coronary arteries and it leads to cardiomyopathy. 

Non-ischemic cardiomyopathy refers to forms of cardiomyopathy not related to known coronary artery disease. The four types of non-ischemic cardiomyopathy include dilated cardiomyopathy, hypertrophic cardiomyopathy, restrictive cardiomyopathy and arrhythmogenic right ventricular dysplasia (ARVD). 


Signs and symptoms of cardiomyopathy include:

  • Shortness of breath or trouble breathing, especially with physical exertion
  • Fatigue
  • Swelling in the ankles, feet, legs, abdomen and veins in the neck
  • Dizziness
  • Lightheadedness
  • Fainting during physical activity
  • Chest pain, especially after physical exertion or heavy meals

Often the cause of the cardiomyopathy is unknown. In some people, however, it's the result of another condition (acquired) or passed on from a parent (inherited).

Contributing factors for acquired cardiomyopathy include:

  • Long-term high blood pressure
  • Heart tissue damage from a heart attack
  • Chronic rapid heart rate
  • Heart valve problems
  • Metabolic disorders, such as obesity, thyroid disease or diabetes
  • Nutritional deficiencies of essential vitamins or minerals, such as thiamin (vitamin B-1)
  • Pregnancy complications
  • Drinking too much alcohol over many years
  • Use of cocaine, amphetamines or anabolic steroids
  • Use of some chemotherapy drugs and radiation to treat cancer
  • Certain infections, especially those that inflame the heart
  • Iron buildup in your heart muscle (hemochromatosis)
  • A condition that causes inflammation and can cause lumps of cells to grow in the heart and other organs (sarcoidosis)
  • A disorder that causes the buildup of abnormal proteins (amyloidosis)
  • Connective tissue disorders


Your doctor may recommend one or more of the following tests to diagnose cardiomyopathy:

  • Electrocardiogram (ECG) – This noninvasive test records the electrical activity of the heart.
  • Holter Monitor (an ambulatory ECG) – This device records the heart’s activity for 24 hours or longer.
  • Event Recorder – This portable ECG can be activated when a patient experiences symptoms of a fast heart rate. It is intended to monitor heart activity over a few weeks or months.
  • Blood Tests
  • Chest X-Ray
  • Stress Test
The goals of cardiomyopathy treatment are to manage your signs and symptoms, prevent your condition from worsening, and reduce your risk of complications. Treatment varies by which type of cardiomyopathy you have.