Cardiomyopathy: A Guide to Heart Muscle Diseases

Medically Reviewed By Dr. Payal Kohli, M.D., FACC
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Cardiomyopathy refers to a group of diseases of the heart muscle. Cardiomyopathy occurs when the heart muscle enlarges or becomes thick or rigid. This weakens the heart muscle and affects its ability to pump blood effectively. In the early stages, cardiomyopathy symptoms may not be present. With time, symptoms can develop, including fatigue, shortness of breath, and swelling in the lower extremities.

People without symptoms may not need treatment. When treatment becomes necessary, options depend on the type and severity of the disease.

A treatment plan may involve medications, lifestyle changes, and, in some cases, medical procedures or surgeries.

This article looks at cardiomyopathy, including types, causes, symptoms, and treatment options. 

What is cardiomyopathy?

Illustration of the types of cardiomyopathy
Types of cardiomyopathy. Healthgrades

Cardiomyopathy is a chronic disease wherein the heart muscle enlarges or becomes thick or rigid. Sometimes, scar tissue develops. Cardiomyopathy weakens the heart muscle, making it difficult to pump blood and deliver it throughout the body.

As the condition progresses, the heart’s electrical system cannot work the way it should. Eventually, cardiomyopathy can lead to heart failure, heart valve problems, and heart arrhythmias.

Often, doctors cannot find an underlying cause of the condition. This is called idiopathic cardiomyopathy.

Cardiomyopathy may be an inherited or acquired condition. Several conditions can lead to the acquired form, including chronic high blood pressure, heart attack, and other heart-related conditions.

The risk of cardiomyopathy is also higher in people who have obesity, who have diabetes, who misuse alcohol or drugs, and who have received certain chemotherapy drugs.

Without treatment, cardiomyopathy can lead to complications and even death.

Contact your doctor if you notice symptoms of cardiomyopathy. Seek immediate medical care (call 911) for chest pain, difficulty breathing, and fainting.

What are the different types of cardiomyopathy?  

There are several types of cardiomyopathy, including:

  • Arrhythmogenic right ventricular dysplasia: This is a rare form of inherited cardiomyopathy. It occurs when scar tissue replaces healthy tissue in the right ventricle. This leads to heart arrhythmias and can cause sudden cardiac arrest in teenagers and young adults.
  • Dilated cardiomyopathy: With this type, the ventricles enlarge and weaken. This is the most common type. The most common causes are coronary artery disease and heart attack.
  • Hypertrophic cardiomyopathy: In this type, the heart’s walls thicken. However, the ventricles often remain a normal size. This type is usually an inherited condition, and it can cause sudden cardiac death.
  • Restrictive cardiomyopathy: With this type, the ventricles become stiff and rigid, most commonly in older adults. The cause is often unknown.
  • Unclassified cardiomyopathy: A number of other types of cardiomyopathy fall into this group. This includes takotsubo cardiomyopathy, or broken heart syndrome.

Read more about types of cardiomyopathy.

What are the symptoms of cardiomyopathy? 

Cardiomyopathy does not always cause symptoms, especially in the early stages.

As the condition progresses, however, most people start to experience symptoms. This can occur rapidly or take some time. Some people may never have any symptoms at all.

Common symptoms of cardiomyopathy

Common cardiomyopathy symptoms result from a weakened heart muscle. They include:

  • abnormal heartbeats or a fluttering feeling in the chest
  • coughing when you lie down
  • dizziness or lightheadedness
  • fatigue
  • shortness of breath
  • swelling in the feet, ankles, lower legs, belly, and veins in the neck

Serious symptoms that might indicate a life threatening condition

In some cases, cardiomyopathy can be life threatening. Seek immediate medical care (call 911) for these serious symptoms:

  • chest pain or pressure
  • difficulty breathing
  • fainting
  • very rapid or irregular heartbeats

Getting regular medical care can help find early signs of a potential heart problem. If cardiomyopathy runs in your family, your doctor may recommend additional screening or prevention plans.

What causes cardiomyopathy? 

The cause of cardiomyopathy varies by type. For example:

  • Arrhythmogenic right ventricular dysplasia: Research suggests that this is mostly an inherited condition.
  • Dilated cardiomyopathy: The cause is often unknown. According to an older paper from 2010, about 30–48% of people inherit it from a parent. Conditions that can cause it include coronary artery disease, heart attack, high blood pressure, diabetes, thyroid disease, and infections. Alcohol, toxins, and certain drugs can also cause it.
  • Hypertrophic cardiomyopathy: Most people inherit this condition from a parent.
  • Restrictive cardiomyopathy: The cause is often unknown, but it can be related to another disease or condition. For example, it may be due to amyloidosis, a connective tissue disorder, hemochromatosis, sarcoidosis, or a certain cancer treatment.

What are the risk factors for cardiomyopathy?

Cardiomyopathy can affect people of all ages and races. Certain types tend to occur more commonly in specific age groups. Dilated cardiomyopathy, which is the most common form, tends to affect more males than females. Arrhythmogenic right ventricular dysplasia affects more teenagers and young adults than older adults.

Other major risk factors for cardiomyopathy include:

  • receiving cancer treatments that can damage the heart, including certain chemotherapy drugs and radiation treatments
  • engaging in chronic alcohol misuse, heavy alcohol use, or drug misuse
  • having diseases that can damage the heart, such as amyloidosis or sarcoidosis
  • having a family history of cardiomyopathy, heart failure, or sudden cardiac arrest
  • having heart-related conditions, such as chronic high blood pressure, coronary artery disease, or a previous heart attack
  • having obesity, diabetes, or another metabolic condition

What lifestyle changes can help treat or reduce your risk of cardiomyopathy?

It is not always possible to prevent cardiomyopathy. This is especially true when the cause is unknown.

Making certain lifestyle changes can help you protect your heart health, lower your risk of cardiomyopathy, and help treat the condition if you develop it. These changes include:

  • avoiding drug use and using alcohol in moderation or not at all
  • eating a heart-healthy diet that is low in sodium and fat
  • getting regular physical exercise
  • lowering stress and getting enough sleep
  • maintaining a moderate body weight
  • quitting smoking or nicotine use
  • treating chronic conditions, such as diabetes and high blood pressure
  • limiting fluids

Ask your doctor for guidance on how much and what types of fluids you should drink. Drinking too many fluids can worsen certain heart conditions.

If you are at risk of cardiomyopathy or already have cardiomyopathy, talk with your doctor about ways to protect your heart. Ask about specific diet, exercise, and weight goals.

How do doctors diagnose cardiomyopathy?

To diagnose cardiomyopathy, your doctor will take a medical history, perform an exam, and order testing.

Questions your doctor may ask include:

  • What symptoms are you experiencing?
  • How severe are your symptoms?
  • Are your symptoms constant, or do they come and go?
  • What, if anything, seems to make your symptoms better or worse?
  • Do you have a family history of cardiomyopathy or other heart problems?
  • What other medical conditions do you have?
  • What medications do you take?

During the physical exam, your doctor will listen to your heart and lungs. They will also examine your neck, abdomen, and legs for signs of swelling or fluid retention.

Tests your doctor may order include: 

  • Blood tests: These gather information about your heart and help your doctor rule out other conditions.
  • Chest X-ray: An X-ray can show the size of your heart and any fluid buildup in your lungs.
  • Electrocardiogram: This painless test measures the rate and rhythm of your heartbeat.
  • Echocardiogram: This imaging test creates pictures of your moving heart and valves.
  • Holter monitor or event monitor: These devices record your heart’s activity over a period of 24 hours or longer.
  • Stress test: This test can see how well your heart tolerates increased work.
  • Cardiac catheterization: This procedure allows your doctor to look inside your heart’s chambers and coronary arteries.
  • Cardiac MRI: This test produces detailed images of the heart and surrounding structures.

In some cases, doctors may recommend genetic testing for inherited forms of cardiomyopathy.

What are the treatments for cardiomyopathy?

When treating cardiomyopathy, there are several treatment goals, including:

  • keeping cardiomyopathy from getting worse
  • managing conditions that cause or contribute to cardiomyopathy
  • preventing complications
  • relieving symptoms

Doctors may accomplish these goals using medications, procedures, or surgeries.


Several types of medications can treat cardiomyopathy. These include:

  • angiotensin-converting enzyme inhibitors, beta-blockers, and angiotensin receptor-neprilysin inhibitors, which lower blood pressure and treat the chemicals that weaken the heart
  • beta-blockers, which slow the heart rate
  • sodium-glucose transport protein 2 inhibitors
  • antiarrhythmics, which regulate the heart rate
  • anticoagulants and antiplatelet drugs, which prevent blood clots
  • diuretics, which remove extra fluid

Procedures and surgeries

Procedures and surgeries to treat cardiomyopathy include:

  • Cardiac resynchronization therapy (CRT): The CRT pacemaker orchestrates the timing among heart chambers.
  • Implantable cardioverter-defibrillator: This device controls abnormal heart rhythms by monitoring the heart and delivering small electrical shocks when necessary.
  • Pacemaker: This implantable device controls abnormal heart rates with electrical impulses.
  • Radiofrequency ablation: This procedure treats heart arrhythmias by destroying abnormal cells in the heart.
  • Septal ablation: This catheter-based procedure shrinks areas of thickened heart muscle. 
  • Septal myectomy: This open-heart surgery involves removing areas of thickened heart muscle to improve blood flow through the heart.
  • Ventricular assist device: This mechanical pump helps your heart pump blood. It involves implantable and external components.

If medications and other treatments stop working, your doctor may recommend a heart transplant.

What are the potential complications of cardiomyopathy? 

Complications of cardiomyopathy can be serious and even life threatening. Potential complications include:

  • Blood clots: These can form in the heart when it cannot pump blood effectively. The clots can cause a heart attack or stroke if they enter the bloodstream.
  • Heart arrhythmias: These irregular heartbeats can increase the risk of blood clots.
  • Heart failure: This occurs when the heart weakens to the point where it cannot supply enough blood to the body.
  • Heart valve problems: These occur when the valves cannot close properly due to the size of the heart muscle. This causes regurgitation, which is the leakage of blood backward through the valve.
  • Sudden death: This is due to cardiac arrest.

How does cardiomyopathy affect quality of life? 

When cardiomyopathy progresses to heart failure, it can affect your quality of life. Health-related quality of life (HRQoL) looks at the impact a condition and its treatment have on a person’s perception of their physical, mental, and social health and well-being. 

Poor HRQoL is related to a higher likelihood of hospitalization and death. Research suggests that declines in HRQoL can lead to more clinical events in people with heart failure.

For many people with heart failure, the physical limitations of the condition are only one aspect of their health perception. Doing social activities, feeling happy in daily life, and having fulfilling family relationships can be just as important.

Seeking interactions through support groups and other social circles can boost HRQoL. This, in turn, may translate into feeling better about your physical health.

Does cardiomyopathy shorten life expectancy? 

How cardiomyopathy affects life expectancy depends on the form of the disease a person has.

People with dilated cardiomyopathy, which is the most common type of cardiomyopathy, are most likely to develop heart failure. About half of these people die within 5 years of developing heart failure.

For some other forms of cardiomyopathy, sudden cardiac death may be the first indication.


There are several forms of cardiomyopathy. The most common type is dilated cardiomyopathy. It often occurs due to an unknown cause, but people can inherit it.

Treatment involves lifestyle changes, medications, and procedures.

Although it is not always possible to prevent cardiomyopathy, following a heart-healthy diet and getting plenty of exercise can help keep your heart as healthy as possible.

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Medical Reviewer: Dr. Payal Kohli, M.D., FACC
Last Review Date: 2022 Feb 24
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