Cardiomyopathy

Cardiomyopathy is a disease of the heart muscle that has many causes, symptoms and treatments.

In cardiomyopathy, the heart muscle becomes enlarged, thick, or rigid. In rare cases, the muscle tissue in the heart is replaced with scar tissue.

As cardiomyopathy worsens, the heart becomes weaker. It's less able to pump blood through the body and maintain a normal electrical rhythm.

This can lead to heart failure or irregular heartbeats called arrhythmias. In turn, heart failure can cause fluid to build up in the lungs, ankles, feet, legs or abdomen.

The weakening of the heart can also cause other complications, such as heart valve problems.

Types of Cardiomyopathy

Dilated Cardiomyopathy

This is the most common type of the disease. It mostly occurs in adults, aged 20 to 60. Men are more likely than women to have this type.

Dilated cardiomyopathy affects the heart's ventricles and atria. These are the lower and upper chambers of the heart, respectively.

Hypertrophic Cardiomyopathy (HCM)

HCM is very common and can affect people of any age. About one in every 500 people has it, affecting men and women equally. Some people who have HCM have no signs or symptoms.

The disease doesn't affect their lives. Others have severe symptoms and complications. For example, they may have shortness of breath, serious arrhythmias, or an inability to exercise.

HCM is a common cause of sudden cardiac arrest in young people, including young athletes.

Restrictive Cardiomyopathy

This type mostly affects older adults. The ventricles (heart chambers) become stiff because abnormal tissue, such as scar tissue, replaces the normal heart muscle.

As a result, the ventricles can't relax normally and fill with blood, and the atria become enlarged. Over time, blood flow in the heart is reduced which can lead to heart failure or arrhythmias.

What is Arrhythmogenic Right Ventricular Dysplasia (ARVD)

ARVD is a rare type of cardiomyopathy that occurs if the muscle tissue in the right ventricle dies and is replaced with scar tissue. This process disrupts the heart's electrical signals and causes arrhythmias.

Symptoms includes fainting after physical activity and palpitations (feelings that your heart is skipping a beat, fluttering, or beating too hard or too fast).

ARVD usually affects teens or young adults and can cause Sudden Cardiac Arrest in young athletes.

Risk Factors for Cardiomyopathy

Cardiomyopathy can be acquired or inherited. “Acquired” means you aren't born with the disease, but develop it due to another disease, condition or factor.

"Inherited" means it’s genetic, your parents passed the gene for the disease on to you. Many times, the cause of cardiomyopathy isn't known.

People of all ages and races may develop cardiomyopathy. However, certain types of the disease are more common in certain groups.

Dilated cardiomyopathy is more common in African Americans than Whites. This type of the disease is also more common in men than women.
Teens and young adults are more likely than older people to have arrhythmogenic right ventricular dysplasia, although it's rare in both groups.

Symptoms of Cardiomyopathy

Some people who have cardiomyopathy never have symptoms. Others don't have any in the early stages of the disease.

As cardiomyopathy worsens and the heart weakens, symptoms of heart failure usually occur. Other symptoms include:

Shortness of breath or trouble breathing, especially with physical exertion
Fatigue (tiredness)
Swelling in the ankles, feet, legs, abdomen and veins in the neck
Dizziness or light-headedness
Fainting during physical activity
Arrhythmia (irregular heartbeats)
Chest pain, especially after physical exertion or heavy meals
Heart murmurs (extra or unusual sounds heard during a heartbeat)

Causes of Cardiomyopathy

Most often the cause of the cardiomyopathy is unknown. In some people, however, doctors are able to identify some contributing factors. Possible causes of cardiomyopathy include:

Long-term high blood pressure
Heart valve problems
Heart tissue damage from a previous heart attack
Chronic rapid heart rate
Metabolic disorders, such as thyroid disease or diabetes
Nutritional deficiencies of essential vitamins or minerals such as thiamin (vitamin B-1), selenium, calcium and magnesium
Pregnancy
Excessive use of alcohol over many years
Abuse of cocaine or antidepressant medications, such as tricyclic antidepressants
Use of some chemotherapy drugs to treat cancer
Certain viral infections, which may injure the heart and trigger cardiomyopathy
Iron buildup in your heart muscle (hemochromatosis)
Genetic conditions

Diagnosis of Cardiomyopathy

Cardiomyopathy can be diagnosed based on a doctor consultation that includes a review of the patient's medical and family histories and a physical exam. Diagnosis also happens from the results of such tests and procedures as:

Blood test
Genetic tests
Chest X-ray
Electrocardiogram (EKG) – a simple test that records the heart’s electrical activity
Echocardiography – a test that uses sound waves to create a moving picture of the heart
Holter and Event Monitors – small, portable devices that record your heart’s electrical activity for a 24-48 hour period
Stress test
Diagnostic Procedures - including cardiac catheterization and coronary angiography