Home > Learn > Heart Disease > What Is Cardiomyopathy?
Untitled Document



Heart Disease
  What Is Cardiomyopathy?

By Stephanie Trelogan, MS

Reviewed by Andy Avins, MD

Cardiomyopathy literally means disease of the myocardium, or heart muscle. In this disease, the heart loses its ability to pump blood and beat at a normal rhythm. The condition tends to start off mild and then worsens fairly quickly. In the most severe cases, cardiomyopathy can lead to congestive heart failure.


Who Gets Cardiomyopathy?

Most cardiomyopathy occurs in men older than 65.
Most cardiomyopathy results as a complication of coronary artery disease (CAD), which occurs when the arteries that deliver blood to the heart become blocked. These cardiomyopathies affect about 1 out of 100 people, usually men over 65 years old. In older age groups, more women develop the disease.

Cardiomyopathies that do not occur as a result of CAD are fairly uncommon, affecting only about 50,000 people in the United States. However, these cardiomyopathies often occur in young people, and they are the leading reason for heart transplantation. Many of these cardiomyopathies are due to genetic causes and tend to run in families.



Types of Cardiomyopathy

There are four general types of cardiomyopathy:

  • Dilated cardiomyopathy is the most common form of cardiomyopathy. It occurs when the heart muscles become weak and cannot pump blood effectively. The weak muscles relax, and allow the chambers of the heart to expand. Most cases of dilated cardiomyopathy are a result of coronary artery disease, but about 30 percent of cases are genetic in origin. Dilated cardiomyopathy occurs in 2 out of 100 people.
  • Hypertrophic cardiomyopathy occurs when the walls of the heart become thicker, which can prevent the blood from flowing through the heart. Hypertrophic cardiomyopathy is fairly rare, occurring in only 2 out of 1000 people. There are several genes that are known to increase a person's risk of developing this disease.
  • Restrictive cardiomyopathy occurs when the heart walls become stiff and can't relax enough to fill with blood. A heart that cannot fill with blood cannot effectively pump blood to the body. The most common cause of restrictive cardiomyopathy is when a protein called amyloid builds up in the heart muscle. However, it also occurs as a result of hemochromatosis or as a result of other heart diseases, some of which are inherited. This type of cardiomyopathy is relatively rare, occurring in 1 out of 1000 people.
  • Arrhythmogenic right ventricular dysplasia is a very rare cardiomyopathy that occurs in one out of every 5,000 people. In this disease, the muscle of the right ventricle is gradually replaced by a layer of fatty tissue. This fatty tissue causes major problems with the heart's rhythm. The most common result of this disease is cardiac sudden death, in which the heart suddenly stops beating. In fact, it accounts for one fifth of all cases of cardiac sudden death in people younger than 35, and is the leading cause of sudden death in young athletes. Although not a lot is known about the disease, somewhere between 30 to 90 percent of cases are familial, and are inherited in an autosomal dominant fashion. This means that a person only has to inherit a mutated version of the gene from one parent in order to be at risk.

Cardiomyopathy can also result from other hereditary syndromes, such as hemochromatosis, diabetes, or some neuromuscular diseases.



More on Other Hereditary Cardiomyopathy Syndromes (Coming Soon)







Signs and Symptoms

Sometimes symptoms of congestive heart failure are the first sign of cardiomyopathy.
Often, people who have cardiomyopathy experience no symptoms before cardiac sudden death occurs. For this reason, it is important to see your doctor regularly if you are at risk for the disease. In some cases people suffering from cardiomyopathy may experience symptoms of congestive heart failure. Common early warning sings of congestive heart failure may include:
  • Shortness of breath (dyspnea)
  • Decreasing ability to tolerate physical exertion
  • Chest pain
  • Fainting (especially after activity)
  • Lightheadedness (especially after activity)
  • Dizziness
  • Sensation of feeling heart beat (palpitations)
  • High blood pressure

There are many forms of heart disease that result in congestive heart failure, so these symptoms may or may not indicate cardiomyopathy. Also, there are other diseases besides heart disease that can cause these symptoms. If you experience any of these symptoms, a doctor can perform a combination of diagnostic tests to clarify the diagnosis.





More on Screening for Heart Disease (Coming Soon)





When cardiomyopathy causes congestive heart failure, then doctors can prescribe drugs to treat those symptoms. However, people with severe congestive heart failure may need to be hospitalized or may require a heart transplant. If the cardiomyopathy results from CAD, then doctors treat that illness through drugs, lifestyle modifications, or surgery to remove blockages in the heart. In most cases, doctors can't treat the cardiomyopathy itself.




Schultheiss, H.-P. & Kühl, U. (1997) Cardiomyopathies and Specific Muscle Diseases. In P. A. Poole-Wilson, et al. (Eds.), Heart Failure. (pp. 423–438). New York, NY: Churchill Livingstone, Inc.

Vosberg, H.-P. & McKenna, W. J. (1997) Cardiomyopathies. In D. L. Rimoin, et al. (Eds.), Emery and Rimoin’s Principles and Practice of Medical Genetics, volume 1 (pp. 843–877). New York, NY: Churchill Livingstone, Inc.

Young, J. B., et al. (1997) Managing Heart Failure With Transplantation, Ventricular Assist Devices, and Cardiomyoplasty. In P. A. Poole-Wilson, et al. (Eds.), Heart Failure. (pp. 827–851). New York, NY: Churchill Livingstone, Inc.

<<Previous Article
Main Topic Page
Next Article>>
 What is Heart Disease?


Untitled Document

©Copyright 2011 Latest Medical, Inc.. All Rights Reserved.
Contact Us