Cardiomyopathy

Cardiomyopathy is a disease that affects the heart muscle, making it harder for your heart to pump blood to the rest of your body. This condition can affect people of all ages and may lead to serious heart problems, but treatment options are available to help manage symptoms and improve quality of life.

Table of contents

• What is cardiomyopathy?
• Types of cardiomyopathy
• Symptoms
• Causes and risk factors
• Diagnosis
• Treatment
• Living with cardiomyopathy
• Complications

What is cardiomyopathy?

Cardiomyopathy is a disease of the heart muscle. The term means that your myocardium (the muscle tissue of your heart) becomes damaged or diseased^[1][2]. When you have cardiomyopathy, your heart muscle can become stretched, thickened, stiff, or filled with scar tissue. This makes it harder for your heart to pump blood effectively to the rest of your body^[1][4].

In a healthy heart, the muscle contracts and relaxes to pump blood throughout your body. With cardiomyopathy, these normal functions become impaired. The heart may have to work harder to pump blood, which can lead to symptoms of heart failure — a condition where the heart cannot pump enough blood to meet the body’s needs^[1][5].

• Heart
• Heart muscle (myocardium)
• Heart chambers (ventricles and atria)

Types of cardiomyopathy

There are several main types of cardiomyopathy, each affecting the heart muscle in different ways^[1][2][6].

Dilated cardiomyopathy

Dilated cardiomyopathy is the most common type. In this condition, the muscle walls of the heart become stretched and thin, so they cannot squeeze properly to pump blood around the body^[4]. The heart’s pumping chamber becomes enlarged, but the muscle walls are thinner and weaker than normal^[17]. This type can affect both children and adults^[4].

Hypertrophic cardiomyopathy

In hypertrophic cardiomyopathy, the heart muscle becomes abnormally thick. The muscle cells enlarge and the walls of the heart chambers thicken^[4]. This thickening usually occurs in the wall between the two lower chambers of the heart. The thickened muscle can make it harder for blood to flow out of the heart and can cause the heart chambers to stiffen^[1][4].

Hypertrophic cardiomyopathy is the most common inherited cardiomyopathy and affects about 1 in 500 people worldwide^[2]. It can occur at many ages, and some people with this condition have no symptoms at all. However, it is the most common cause of sudden unexpected death in young people and young athletes^[4][5].

Restrictive cardiomyopathy

Restrictive cardiomyopathy is the least common type. The walls of the main heart chambers become stiff and rigid and cannot relax properly after contracting^[4]. This means the heart cannot fill up properly with blood between heartbeats. While the heart muscle may not be thickened, it becomes less flexible, which reduces the amount of blood that can be pumped to the rest of the body^[6].

This type is most often diagnosed in children, although it can develop at any age. In many cases, the cause is unknown, although sometimes the condition can be inherited^[4].

Arrhythmogenic right ventricular cardiomyopathy

Arrhythmogenic right ventricular cardiomyopathy is a rare form that occurs when the muscle of the heart’s right lower chamber is replaced by thick or fatty scar tissue^[9]. The proteins that usually hold the heart muscle cells together are abnormal. This scarring interferes with the heart’s electrical signals and can make it difficult for the heart to pump blood effectively^[4]. This type affects about 1 in 5,000 people^[9].

Other types

There are several other specific types of cardiomyopathy, including^[2]:

• Peripartum cardiomyopathy — a rare form that can occur near the end of pregnancy or up to a year after giving birth^[5]
• Takotsubo cardiomyopathy (also called broken heart syndrome or stress-induced cardiomyopathy) — triggered by highly stressful experiences
• Alcohol-induced cardiomyopathy — caused by excessive alcohol consumption over time
• Chemotherapy-induced cardiomyopathy — resulting from cancer treatment

Symptoms

Some people with cardiomyopathy do not have any symptoms, especially in the early stages of the disease^[1][2]. For others, symptoms appear as the condition becomes worse. Symptoms are similar to those seen in heart failure^[6].

Common symptoms of cardiomyopathy include^[1][2]:

• Shortness of breath, especially during physical activity or even at rest
• Fatigue or tiredness, even after getting rest
• Swelling in the legs, ankles, feet, stomach area, or neck
• Chest pain, especially after physical activity or heavy meals
• Heartbeats that feel rapid, pounding, or fluttering (heart palpitations)
• Dizziness or lightheadedness
• Fainting or feeling like you might faint
• Trouble lying flat to sleep
• Cough while lying down
• Bloating of the stomach area due to fluid buildup

Symptoms tend to get worse unless they are treated. In some people, the condition becomes worse quickly, while in others it might not become worse for a long time^[1].

You should see your healthcare professional if you have any symptoms of cardiomyopathy. Call emergency services immediately if you faint, have trouble breathing, or have chest pain that lasts for more than a few minutes^[1].

Causes and risk factors

Cardiomyopathy can be caused by inherited genetic problems or acquired through other medical conditions. Sometimes the cause is unknown^[2][5].

Inherited causes

Many types of cardiomyopathy are inherited, meaning they run in families. Researchers have found thousands of genetic mutations that can cause cardiomyopathies^[2]. If you have cardiomyopathy, your blood relatives may also be at risk and may need to be checked or have genetic testing^[19].

Acquired causes

Other causes of cardiomyopathy include^[2][5]:

• Coronary artery disease — blockages in the arteries that supply blood to the heart
• Heart attack — damage to the heart muscle from blocked blood flow
• High blood pressure that is not well controlled
• Viral infections that cause inflammation of the heart muscle
• Heart valve disease — problems with the flaps that control blood flow through the heart
• Diabetes — high blood sugar levels over time
• Thyroid disease — problems with the gland that controls metabolism
• Autoimmune diseases — conditions where the immune system attacks the body’s own tissues
• Alcohol or drug abuse — especially long-term use of cocaine or excessive alcohol
• Pregnancy — in rare cases, cardiomyopathy can develop during or after pregnancy
• Chemotherapy or radiation — treatments for cancer that can damage the heart
• Amyloidosis — a rare disease where abnormal proteins build up in organs
• Hemochromatosis — a disorder where too much iron builds up in the body
• Sarcoidosis — a condition that causes inflammation in various organs

Risk factors

Certain factors increase your risk of developing cardiomyopathy^[2]:

• Family history of heart failure, cardiomyopathy, or sudden cardiac arrest
• Personal history of heart attacks
• Long-term alcohol or drug use
• Pregnancy
• A highly stressful experience, such as the loss of a loved one
• Radiation or chemotherapy treatment for cancer
• Being overweight (body mass index higher than 30)

Diagnosis

To diagnose cardiomyopathy, your healthcare professional will examine you and ask questions about your personal and family medical history. They may ask when your symptoms occur and whether exercise triggers them^[10].

If your healthcare provider suspects you have a heart condition, they may refer you to a cardiologist — a doctor who specializes in heart disease. The cardiologist will perform a full assessment that may include various diagnostic tests^[2].

Diagnostic tests

Tests used to diagnose cardiomyopathy may include^[2][10]:

• Blood tests — to check iron levels and see how well your kidney, thyroid, and liver are working. One blood test can measure a protein called B-type natriuretic peptide (BNP), which rises during heart failure
• Electrocardiogram (ECG or EKG) — a quick, painless test that measures the electrical activity of your heart using sticky patches placed on your chest
• Echocardiogram — uses sound waves to create moving pictures of your beating heart, showing how blood flows through the heart and heart valves
• Chest X-ray — shows the condition of your lungs and heart and can reveal if your heart is enlarged
• Exercise stress test — involves walking on a treadmill or pedaling a stationary bike while your heart is monitored
• Heart MRI — uses magnets and radio waves to create detailed images of your heart’s soft tissues
• Cardiac CT — uses X-rays to create detailed pictures of your heart
• Cardiac catheterization — involves inserting a thin tube into a blood vessel and threading it to your heart to measure pressure and blood flow
• Myocardial biopsy — removal of a small sample of heart tissue for examination under a microscope
• Ambulatory monitoring — wearing a device that records your heart rhythm over time

Treatment

Cardiomyopathy treatments do not cure the condition, but they can help manage symptoms, slow the progression of the disease, and prevent serious complications^[2][12].

If you have cardiomyopathy but no symptoms, you may not need treatment right away. Some types that occur suddenly may even go away on their own^[12].

Your treatment plan will depend on the type of cardiomyopathy you have, how serious it is, and whether you have any complications^[12]. Treatment may include medicines, procedures, and devices.

Medications

Different medicines are used to treat cardiomyopathy symptoms^[12]:

• Diuretics and aldosterone antagonists — help remove extra fluid and sodium from your body, reducing the amount of blood the heart must pump
• Beta blockers — help slow your heart rate and reduce blood pressure
• ACE inhibitors and angiotensin receptor blockers — help relax blood vessels and lower blood pressure
• Medications for abnormal heart rhythms — help control irregular heartbeats

Implantable devices

For some people, a device implanted in the chest can help manage cardiomyopathy^[16]:

• Pacemaker — a small device that helps control abnormal heart rhythms by sending electrical signals to make your heart beat regularly
• Implantable cardioverter-defibrillator (ICD) — monitors your heart rhythm and delivers an electrical shock if it detects a dangerous irregular heartbeat. This can prevent sudden cardiac death in people at high risk
• Cardiac resynchronization therapy (CRT) — a special type of pacemaker that helps both sides of the heart beat together more efficiently

Surgical procedures

Some people may need surgery to treat cardiomyopathy^[16]:

• Septal myectomy — surgery to remove thickened heart muscle that blocks blood flow, primarily used for hypertrophic cardiomyopathy
• Mitral valve repair — surgery to fix a leaky heart valve
• Ventricular assist device (VAD) — a mechanical pump that helps the heart pump blood, used when heart failure becomes severe
• Heart transplant — replacement of the damaged heart with a healthy donor heart, considered when cardiomyopathy is very severe and other treatments are not working^[2]

Living with cardiomyopathy

If you have cardiomyopathy, making healthy lifestyle changes and following your treatment plan can help you live better with the condition^[19][24].

Follow your treatment plan

Visit your healthcare provider regularly to monitor your condition. Be honest about any problems you’re having with your treatment plan. Not following your provider’s advice could result in serious or life-threatening complications^[24].

Stay physically active

Having cardiomyopathy may mean you get tired more quickly, but this shouldn’t keep you from being active. Regular physical activity can actually help improve your symptoms and general health^[24][26]. Your healthcare provider will advise you about the level and amount of exercise that is safe for you.

Eat a healthy diet

A healthy, balanced diet can help improve your symptoms and general health^[26][28]. Your diet should include:

• Plenty of fruits and vegetables — aim for at least 5 portions a day
• Meals based on starchy foods like potatoes, bread, rice, or pasta
• Some protein from beans, fish, eggs, or meat
• Low levels of saturated fat, salt, and sugar

You may also be given advice about limiting the amount of fluid you drink if you have heart failure^[26].

Make lifestyle changes

Other important lifestyle changes include^[19][26]:

• Stop smoking — if you smoke, quitting can improve your overall health and reduce your risk of complications
• Limit alcohol — ask your doctor about safe levels of alcohol consumption. If your cardiomyopathy is related to alcohol, you may need to stop drinking entirely
• Maintain a healthy weight — losing weight if you’re overweight can reduce strain on your heart
• Get vaccinated — get the annual flu vaccine and pneumococcal vaccination to reduce your risk of infections
• Manage stress — find healthy ways to cope with stress
• Get enough sleep — aim for adequate rest each night

Monitor your condition

You may be asked to help monitor your condition between appointments. For example, your care team may suggest weighing yourself regularly so any changes in your weight, which could be a sign of a problem, are picked up quickly^[26].

Contact your healthcare provider if your symptoms are getting worse or you develop new symptoms^[26].

Complications

As cardiomyopathy worsens, it can lead to other serious heart problems^[2][19]:

• Heart failure — when the heart fails to pump enough blood around the body at the right pressure
• Arrhythmias — irregular heartbeats that can be dangerous
• Heart valve disease — problems with the valves that control blood flow through the heart
• Blood clots — blood can pool in the weakened heart and form clots. If a clot breaks free, it can cause a stroke if it reaches the brain
• Sudden cardiac arrest — the heart suddenly and unexpectedly stops beating
• Cardiogenic shock — a life-threatening condition where the heart can’t pump enough blood and oxygen to vital organs

If you experience symptoms such as sudden chest pain, severe shortness of breath, or fainting, call emergency services immediately^[19].