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Overview of Cardiomyopathy


Tisha Suboc

, MD, Rush University

Last full review/revision Mar 2021| Content last modified Mar 2021

Cardiomyopathy refers to progressive impairment of the structure and function of the muscular walls of the heart chambers.

There are three main types of cardiomyopathy:

The main types of cardiomyopathy may overlap, that is, people may have features of more than one type.

The term cardiomyopathy is used only when a disorder directly affects the heart muscle. Other heart disorders such as coronary artery disease and heart valve disorders, as well as high blood pressure, also can eventually cause the ventricles to enlarge or thicken. However, doctors do not classify the heart muscle problems caused by those disorders as cardiomyopathies.

Types of Cardiomyopathy

There are three main types of cardiomyopathy—dilated, hypertrophic, and restrictive.

Types of Cardiomyopathy

Cardiomyopathy can be caused by many disorders, or it may have no identifiable cause.

Cardiomyopathies often result in the heart not pumping blood adequately. This can cause symptoms of heart failure, including shortness of breath and fatigue. Some cardiomyopathies may also cause chest pain, fainting, abnormal heart rhythms, or sudden death.

To diagnose a cardiomyopathy, doctors ask whether the person has a family history of cardiomyopathy and then do blood tests, electrocardiography, chest x-ray, echocardiography, radionuclide imaging of the heart, and magnetic resonance imaging of the heart . In some people, doctors take a sample of tissue from the inner wall of the heart to examine under a microscope (endomyocardial biopsy). Other tests are done as needed to determine the cause. Treatment depends on the specific type and cause of cardiomyopathy.

More Information

The following are some English-language resources that may be useful. Please note that THE MANUAL is not responsible for the content of these resources.

  • American Heart Association: Cardiomyopathy in adults: Provides comprehensive information on symptoms, diagnosis, and treatment of cardiomyopathies
  • American Heart Association: Pediatric cardiomyopathies: Provides comprehensive information on diagnosis, including genetic diagnosis and treatment of cardiomyopathy in children

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