context: Restrictive cardiomyopathy is when the walls of the lower chambers of your heart (called the ventricles) are too rigid to expand as they fill with blood. The pumping ability of the ventricles may be normal, but it's harder for the ventricles to get enough blood. With time, the heart can't pump properly. This leads to heart failure. Many people with this have none or just minor ones, and they live a normal life. Other people have ones that get more severe as the heart gets worse. Symptoms can happen at any age and may include: Shortness of breath (at first with exercise, but eventually at rest, too) Fatigue Inability to exercise Swelling of the legs and feet Weight gain Nausea, bloating, and poor appetite Palpitations (fluttering in the chest due to abnormal heart rhythms) Fainting Chest pain or pressure Its cause is often unknown but may include: Buildup of scar tissue Buildup of proteins in the heart muscle (your doctor may call this amyloidosis) Chemotherapy or chest exposure to radiation Too much iron in the heart (also called hemochromatosis) Other diseases In some cases, restrictive cardiomyopathy may be confused with something called constrictive pericarditis. That's where the layers of the sac that surrounds the heart (called the pericardium) become thickened, calcified, and stiff. Your doctor will figure out if you have restrictive cardiomyopathy based on: Your symptoms Your family's history of heart disease A physical exam Blood tests An electrocardiogram A chest X-ray An echocardiogram An exercise stress test Cardiac catheterization A CT scan An MRI A biopsy of the heart muscle (your doctor may call this a myocardial biopsy) is sometimes done to figure out the cause. A tissue sample is taken from your heart and looked at under a microscope. It's usually focused on treating the cause. Usually, your doctor will suggest lifestyle changes and medications. Lifestyle changes might include: Diet: Once you have symptoms like shortness of breath or fatigue, how much sodium you get from food becomes important. You'll be told how strict you need to be. It's a good idea to follow those instructions even when your symptoms get better. Exercise: Your doctor will let you know if it's a good idea for you to exercise. While being active is generally good for the heart, people with this may get very tired and short of breath, even after just a little bit of activity. Therefore, experts suggest you: Take frequent breaks. Exercise at a time of day when you have the most energy. Start slow, gradually building up strength and endurance. Heavy weightlifting is not recommended. Medications: Some people may get better by taking types of drugs called beta-blockers and ACE inhibitors. If symptoms are still around, your doctor may add other medicines like digoxin, diuretics, and aldosterone inhibitors. If you have an arrhythmia, your doctor may prescribe something to control your heart rate or make the arrhythmia happen less often. Therapy may also be given to treat things like sarcoidosis, amyloidosis, and hemochromatosis. Your doctor will let you know which medications are best for you. In some cases, if the condition is severe, your doctor may talk to you about a heart transplant.