Restrictive cardiomyopathy

The heart is made up of an outer envelope (pericardium), a muscular layer (myocardium), and an inner envelope (endocardium). Restrictive cardiomyopathy is a rare heart disease in which a thickening of the myocardium occurs, preventing the heart from dilating and filling properly.

How is it produced?

The myocardium is the muscle of the heart that allows it to perform its pump function. In restrictive cardiomyopathy, the heart becomes stiff so it cannot relax properly during diastole, that is, during the time in which it dilates and the blood returns to the heart filling it. In more advanced stages, the function of contraction (systole) and pumping of the blood can also be affected.

The cause of this disease may be unknown (it occurs frequently after a heart transplant) or it may be due to diseases that cause the myocardium to thicken such as amyloidosis, hemochromatosis or sarcoidosis, infiltration by a tumor or fibrosis by radiation .

Symptoms

The inability to adequately fill the heart generates a series of symptoms derived from a lower amount of blood pumping, appearing dyspnea or shortness of breath, fatigue and accumulation of fluid in the legs (edema), abdomen (ascites) and an increase in the size of the liver.

Diagnosis

Diagnosis is based on physical examination and medical signs such as abnormal cardiac auscultation and distended neck veins. It is also supported by a series of tests:

• Alterations in the recording of the electrocardiogram.
• Echocardiography and magnetic resonance imaging allow us to see the thickening of the walls of the ventricles and the difficulty of relaxing them.
• Cardiac catheterization is a test in which, by inserting a catheter that reaches the heart chambers, it is possible to measure the pressures and the amount of blood that the heart pumps in each contraction. In restrictive cardiomyopathy, the stiffness of the heart maintains high pressures and expels less blood.
• heart muscle biopsy. Restrictive cardiomyopathy can be difficult to differentiate from another disease (constrictive pericarditis). A heart muscle biopsy makes it possible to take a sample of muscle tissue that appears thickened in cardiomyopathy.

Treatment

Treatment is usually ineffective and is mainly focused on improving impaired heart function and its consequences as well as the patient's quality of life.

The restriction of salt in the diet and drugs that facilitate the function of the heart and the elimination of fluids (diuretics) are recommended.

The specific treatment of the underlying disease that is causing the cardiomyopathy is also indicated in those cases where possible.

Corticosteroids may be used under certain circumstances, and if heart function is severely impaired, heart transplantation may be considered.

Prevention

There are no known measures to prevent this disease.