Definition Restrictive cardiomyopathy is a condition in which the walls of the heart become thick and rigid. The heart is then not able to fill with a normal amount of blood.
What is going on in the body? In a person with restrictive cardiomyopathy, the muscle in the walls of the heart becomes thickened and less elastic. The heart then cannot fill with blood properly. Blood can, in effect, "back up" into the lungs and the rest of the body. This can lead to failure of the heart, or Congestive heart failure.
What are the signs and symptoms of the disease? Symptoms of restrictive cardiomyopathy are mostly due to the rise in pressure from blood backing up in the lungs and other parts of the body. These symptoms may include:
What are the causes and risks of the disease? When the cause of the heart muscle thickening is unknown, this condition is called primary restrictive cardiomyopathy. However, other diseases can cause this condition. These cases are called secondary restrictive cardiomyopathy. Examples of causes include:
amyloidosis, a condition caused by abnormal protein deposits that can affect the heart and many other areas of the body
sarcoidosis, a condition that causes inflammation in many areas of the body for unknown reasons
inherited conditions
haemochromatosis, a condition caused by too much iron in the body. The extra iron can get deposited into the heart and other organs.
Loffler's syndrome, a condition caused by an abnormally high number of certain blood cells. These cells can cause damage to the heart and other organs.
endomyocardial fibrosis, a disease of unknown cause that results in scarring of the heart
In some cases, the cause cannot be found.
What can be done to prevent the disease? In most cases, nothing can be done to prevent restrictive cardiomyopathy. Prevention is related to the cause. Early treatment of sarcoidosis and haemochromatosis may help prevent some cases.
How is the disease diagnosed? Diagnosis of restrictive cardiomyopathy begins with a history and physical examination. The doctor may order a variety of tests, including:
A biopsy of the inside of the heart is often needed to confirm the diagnosis. A biopsy is a procedure to remove a small piece of tissue from the body. A heart biopsy is done by a procedure called cardiac catheterisation.. This involves inserting a tube through the skin and into an artery, usually in the groin. The tube is moved forward in the artery until it reaches the heart. A small tool can be passed through the tube to remove a small piece of heart muscle. This piece can be sent to the laboratory for further examination and testing.
What are the long-term effects of the disease? congestive heart failure almost always occurs in this condition. Restrictive cardiomyopathy often has a very poor outcome and commonly causes death.
What are the risks to others? There are no risks to others.
What are the treatments for the disease? There are few treatments for restrictive cardiomyopathy. Treatment is directed at the cause, when possible, to prevent further heart damage. For example, a person with haemochromatosis often needs to have his or her blood filtered by a machine to remove excess iron. Medications called diuretics, or "water" pills, and heart medications are used to treat the congestive heart failure.
Medications to suppress the immune system can help delay heart damage in many cases. This kind of treatment does not offer a cure. In rare cases, surgery to remove some of the scarred heart tissue may improve symptoms. For cases that don't respond to these measures, a heart transplant may be the only treatment.
What are the side effects of the treatments? Side effects depend on the treatment used. Diuretics and heart medications can cause allergic reactions, salt imbalances, stomach upset, and other effects. Medications that suppress the immune system can result in infections, kidney or liver damage, and other effects. Surgery is associated with bleeding, infection, and allergic reactions to anaesthesia. A heart transplant is a high-risk operation and the body may reject the new heart.
What happens after treatment for the disease? A person with restrictive cardiomyopathy will need lifelong treatment.
How is the disease monitored? The person will work together with the doctor to monitor symptoms, the effects of treatment, and medications. This often involves blood tests and repeated imaging tests of the heart. Any new or worsening symptoms should be reported to the doctor.
Author: Eric Berlin, MD Reviewer: HealthAnswers Australia Medical Review Panel Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia Last Updated: 1/10/2001 Contributors Potential conflict of interest information for reviewers available on request
