Skip to Content

Restrictive Cardiomyopathy

Restrictive cardiomyopathy (RCM) is a condition where the chambers of the heart become stiff over time. Though the heart is able to squeeze well, it’s not able to relax between beats normally. This makes it harder for the heart to fill with blood. The blood backs up in the circulatory system. This can cause fluid to build up in the body including the lungs, which leads to many of the symptoms of the condition. It also increases the pressure inside the ventricles and the atria can become enlarged. There is also an increased risk for irregular heart rhythms. Eventually this disease makes the heart unable to pump as much blood out to the body as it normally would. Most people with RCM eventually develop heart failure. RCM is a fairly uncommon form of cardiomyopathy. It can affect people at any age.

What causes restrictive cardiomyopathy?

Many different causes can lead to RCM. These are mostly other health conditions. They include:

  • Amyloidosis, an abnormal buildup of protein in organs and tissues. This is the most common cause of RCM.
  • Hemochromatosis, a condition that occurs from an iron overload in the heart and body
  • Sarcoidosis, a disease that causes scarring of the heart
  • Eosinophilic endomyocardial disease, a disease caused by certain tumors, lymphomas, or parasitic disease
  • Scleroderma, a disease that causes hardening of tissues in the body
  • Radiation-induced heart disease, a condition that may occur from cancer radiation treatment
  • Certain rare genetic conditions. You may have increased risk if you have a family member with RCM.

In some cases, the cause of RCM is not known.

What are the symptoms of restrictive cardiomyopathy?

In its early stages, RCM may not have any symptoms. These may worsen slowly or more quickly. Some symptoms include:

  • Shortness of breath with exertion. This may progress to shortness of breath when at rest.
  • Shortness of breath when lying flat
  • Fatigue
  • Swelling in the legs and other areas
  • Fainting
  • Weakness or lightheadedness
  • Cough
  • Abnormal heart rhythms

For more information on this topic, visit our Health Library.