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Restrictive Cardiomyopathy

(Infiltrative Cardiomyopathy)


Tisha Suboc

, MD, Rush University

Reviewed/Revised Nov 2022
Topic Resources

Restrictive cardiomyopathy includes a group of heart disorders in which the walls of the ventricles (the two lower chambers of the heart) become stiff, but not necessarily thickened, and resist normal filling with blood between heartbeats.

  • Restrictive cardiomyopathy may occur when heart muscle is gradually infiltrated or replaced by scar tissue or when abnormal substances accumulate in the heart muscle.

  • Shortness of breath, fluid accumulation in the tissues, abnormal heart rhythms, and awareness of heartbeats are common symptoms.

  • The diagnosis is based on results of a physical examination, electrocardiography, echocardiography, radionuclide imaging, magnetic resonance imaging, cardiac biopsy, and cardiac catheterization.

  • Treatment is not often helpful, although sometimes doctors are able to treat the cause.

The Heart

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, also can eventually cause the ventricles to enlarge and heart failure. However, doctors do not classify the heart muscle problems caused by those disorders as cardiomyopathies.

There are two basic types of restrictive cardiomyopathy:

  • The heart muscle is gradually replaced by scar tissue.

  • Abnormal substances accumulate in the heart muscle.

A congenital form of restrictive cardiomyopathy occurs in infants and children who have endocardial fibroelastosis. In this rare disorder, a thickened layer of fibrous tissue lines the left ventricle. Endomyocardial fibrosis commonly occurs in tropical regions and affects both the left and right ventricles.


Scarring of heart muscle may result from injury due to radiation therapy that may be given for treatment of a chest tumor.

Accumulation of abnormal substances

Various substances may accumulate in the heart as a result of various disorders. The accumulated substances interfere with the heart muscle's ability to contract and relax.

In amyloidosis Amyloidosis Amyloidosis is a rare disease in which abnormally folded proteins form into collections called amyloid fibrils that accumulate in various tissues and organs, sometimes leading to organ dysfunction... read more Amyloidosis , amyloid (an unusual protein not normally present in the body) may accumulate in heart muscle and other tissues. Amyloidosis is more common among older people and can sometimes be hereditary.

Other examples are tumors and granuloma tissue (abnormal collections of certain white blood cells that form in response to chronic inflammation), which, for example, develops in people who have sarcoidosis Sarcoidosis Sarcoidosis is a disease in which abnormal collections of inflammatory cells (granulomas) form in many organs of the body. Sarcoidosis usually develops in people aged 20 to 40 years, most often... read more Sarcoidosis .

Symptoms of Restrictive Cardiomyopathy

Usually, symptoms do not occur during rest, because in restrictive cardiomyopathy, the heart can supply the body with enough blood and oxygen during rest, even though the stiff heart resists filling with blood. Symptoms occur during exercise, when the stiff heart cannot pump enough blood to meet the body’s increased need for blood and oxygen.

Diagnosis of Restrictive Cardiomyopathy

  • Echocardiography and magnetic resonance imaging (MRI) of the heart

  • Sometimes, cardiac catheterization and cardiac biopsy

Restrictive cardiomyopathy is one of the possible causes investigated when a person has heart failure.

The diagnosis is based largely on the combined results of a physical examination, electrocardiography (ECG), chest x-ray, and echocardiography. ECG can typically detect abnormalities in the heart’s electrical activity, but these abnormalities are not specific enough for a diagnosis.

Doctors sometimes do cardiac catheterization Cardiac Catheterization and Coronary Angiography Cardiac catheterization and coronary angiography are minimally invasive methods of studying the heart and the blood vessels that supply the heart (coronary arteries) without doing surgery. These... read more Cardiac Catheterization and Coronary Angiography in people with severe symptoms, such as chest pain, difficulty breathing, or fainting. Cardiac catheterization is an invasive procedure in which a catheter is threaded from a blood vessel in the arm, neck, or leg into the heart. The procedure is used to measure pressures in the heart chambers and to remove a sample of heart muscle for examination under a microscope (biopsy), which may enable doctors to identify an infiltrating substance.

Sometimes, other specialized tests may be needed to determine the disorder causing the cardiomyopathy.

More than half the time, no specific cause for restrictive cardiomyopathy is found (idiopathic restrictive cardiomyopathy).

Treatment of Restrictive Cardiomyopathy

  • Treatment of the disorder causing restrictive cardiomyopathy

Sometimes, the disorder causing restrictive cardiomyopathy can be treated to prevent heart damage from worsening or even to partially reverse it. For example, removing blood at regular intervals reduces the amount of stored iron in people with iron overload. People who have sarcoidosis may take corticosteroids, which cause the granuloma tissue to disappear. Corticosteroids may also be helpful in eosinophilic infiltrative disorders. Medications used to decrease or control the symptoms of some types of amyloidosis Treatment Amyloidosis is a rare disease in which abnormally folded proteins form into collections called amyloid fibrils that accumulate in various tissues and organs, sometimes leading to organ dysfunction... read more Treatment may be helpful. However, many cases of restrictive cardiomyopathy have no specific treatment.

Survival varies depending on the cause. But prognosis is typically poor because the diagnosis is often made very late.

For most people, treatment is not very helpful. For example, diuretics, which are usually taken to treat heart failure, may help people who have troublesome leg swelling or shortness of breath. However, these medications also reduce the amount of blood entering the heart, which can worsen restrictive cardiomyopathy instead of improving it.

Medications commonly used in heart failure to reduce the heart’s workload, such as angiotensin-converting enzyme (ACE) inhibitors, are usually not helpful because they reduce blood pressure too much. As a result, not enough blood reaches the rest of the body.

Similarly, digoxin is usually not helpful and is sometimes harmful in people with amyloidosis. Beta-blockers and calcium channel blockers are poorly tolerated in people with restrictive cardiomyopathy and have not been shown to improve survival.

Antiarrhythmics may be given to prevent or reduce symptoms in people with fast or irregular heart rhythms.

More Information

The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

Drugs Mentioned In This Article

Generic Name Select Brand Names
Digitek , Lanoxicaps, Lanoxin, Lanoxin Pediatric
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