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Our hearts are made of highly elastic muscle that expand and contract over 115,200 times a day. However, sometimes the heart muscle can become rigid or thick, which makes it more difficult for the organ to pump blood out of the heart. This condition is called cardiomyopathy. 

Cardiomyopathy is often inherited, although it may be a result of issues including heart tissue damage from a heart attack, long-term high blood pressure, metabolic disorders including obesity and diabetes, nutritional deficiencies, and/or drug and alcohol abuse.

If untreated, cardiomyopathy can weaken the heart, leading to more serious conditions, including lessened blood flow, arrhythmia (irregular heartbeats), problems with the heart’s valves and heart failure. However, at the  Cardiomyopathy Inherited Cardiovascular Disease Program at Yale Medicine, we use cutting-edge technologies to diagnose the condition before it evolves to an advanced stage. 

What are the different types of cardiomyopathies?

There are three main types of cardiomyopathies:

Dilated cardiomyopathy, the most common type, causes the left ventricle (the heart’s main chamber) to enlarge, making it difficult to effectively pump blood out of the heart. This condition is most common in middle-aged men, although it can affect men and women of all ages. Most people diagnosed with dilated cardiomyopathy have a family history of the condition, but it can also be a result of coronary heart disease, chemotherapy, an infection or substance abuse. If untreated, dilated cardiomyopathy may lead to heart failure.

Hypertrophic cardiomyopathy thickens the walls of the heart, making it difficult to pump blood. Most people diagnosed with hypertrophic cardiomyopathy have a family history of the condition, and it is believed to be the result of a genetic mutation. It can be diagnosed at any age and tends to be most severe when discovered during childhood.

Restrictive cardiomyopathy causes the heart muscle to become less elastic, making it hard for the heart to expand and fill with blood between heartbeats. It is the least common cardiomyopathy and tends to affect older patients, although it can be diagnosed at any age.

Other types of cardiomyopathies include arrhythmogenic right ventricular dysplasia, in which heart rhythm problems arise as the right ventricle (the heart’s lower right chamber) is replaced with scar tissue and unclassified cardiomyopathies. Both are extremely rare.

What are the symptoms of cardiomyopathies?

“Cardiomyopathy symptoms are highly varied, and may include chest pain, palpitations, coughing when lying down, fatigue, shortness of breath, dizziness, and passing out,” says Daniel Louis Jacoby, MD, director of Yale Medicine’s General & Advanced Heart Failure Program and the Cardiomyopathy Inherited Cardiovascular Disease Program. “But some patients experience no symptoms at all.”

He emphasizes that even people with no symptoms may be at significant risk if they are not treated. “It’s important that we don’t put our heads in the sand,  Dr. Jacoby says, “because the serious complications arise when we ignore what’s going on or treat patients without the proper support.”

In most cases, symptoms will continue to get worse until they are treated, although they may worsen over long periods of time, making it more difficult to recognize their severity.

How are cardiomyopathies diagnosed?

“Providing an accurate diagnosis for patients with cardiomyopathies is very frequently a challenge,” says Dr. Jacoby. “It becomes clear that something is not right, but it’s not always clear what specifically is not right.”

Because of the complexity of the disease, it may take several visits to accurately diagnose a specific patient’s condition. Some of the tests that may help lead to a proper diagnosis include:

  • Blood tests to check iron levels and kidney, liver and thyroid function
  • Cardiac catheterization to measure the force of blood as it pumps through the heart and, if necessary, to conduct a heart biopsy
  • Cardiac computerized tomography (CT) scan to evaluate the functioning of the heart and heart valves
  • Coronary angiogram to check for blood vessel blockage
  • Chest X-ray to check for heart chamber enlargement
  • Echocardiogram to examine the heart valves and a cardiac MRI (magnetic resonance imaging) scan if the echocardiogram is inconclusive
  • Electrocardiogram to check for abnormal heart rhythms
  • Genetic testing or screening
  • Treadmill stress test to evaluate symptoms and see whether exercise brings on abnormal heart rhythms

How are cardiomyopathies treated?

Treating cardiomyopathies involves managing any present symptoms and preventing the condition from getting worse and leading to complications. Treatments include:

  • Lifestyle changes such as limiting salt intake and watching the patient’s weigh
  • Medications that may remove blood clots or relax the heart or improve its pumping ability
  • Devices such as defibrillators to control the heart’s rhythms 
  • Surgical procedures that remove damaged areas of the hearts.
  • Heart transplant in rare cases when other treatment has not worked

“Cardiomyopathies involve unique sets of symptoms and risks that require specialty knowledge and experience to appropriately manage,” says Dr. Jacoby.

“Successful treatment often involves multiple members of the family and support from patient’s peers and other patients managing the disease," he says. "There are very dedicated support groups for patients and their families to allow them to share their knowledge and experience.

"At Yale Medicine, we put together an action plan for each patient that makes sense for that patient and their family.”

What is the outlook for patients with cardiomyopathies?

In most cases, the biggest challenge is to accurately diagnose a patient’s condition.

“Once diagnosed, the outlook is overall generally good as we have the full range of treatment options at our disposal, including specially trained surgeons and geneticists,” says Dr. Jacoby. “There are also ongoing clinical trials that may be of benefit for specific patients.”

What makes Yale Medicine’s approach to diagnosing and treating cardiomyopathies unique?

In addition to cutting-edge technology and treatment options, Yale Medicine has world-class doctors, surgeons and researchers. Yale Medicine’s approach to the diagnosis and treatment of this complex disease means putting patients first. 

“No one wants to walk around feeling anxious,” says Dr. Jacoby. “We work to provide our patients and their families with thoughtful reassurance, including knowledge about the disease and a specific care plan that fully integrates the needs of both patient and family.

"No matter what stage a patient is at, whether the problem has become serious or it turns out to be relatively minor, we feel it is crucial not just to provide the patient what he or she needs to remain safe and become healthier, but for them to understand what we’re planning to do and why we’re doing it.”