Cardiomyopathy is disease of abnormal heart muscle in which the heart muscle becomes weakened, stretched, or has another structural problem. It often contributes to the heart's inability to pump or function well.
Many people with cardiomyopathy have heart failure.
Dilated cardiomyopathy involves enlargement of the heart muscle and is the most common type of cardiomyopathy. The heart muscle is weakened and cannot pump blood efficiently. Decreased heart function affects the lungs, liver, and other body systems.
There are many types of cardiomyopathy, with different causes. Some of the more common ones are:
- Dilated cardiomyopathy (also called idiopathic dilated cardiomyopathy) is a condition in which the heart becomes weak and the chambers get large. As a result, the heart cannot pump enough blood out to the body. It can be caused by many medical problems.
- Hypertrophic cardiomyopathy (HCM) is a condition in which the heart muscle becomes thick. This makes it harder for blood to leave the heart. This type of cardiomyopathy is most often passed down through families.
Hypertrophic cardiomyopathy is the thickening of the muscles that make up the heart. The thickening may interfere with the normal functioning of the heart by narrowing the outflow of the ventricle; reducing the ability of the heart to relax and fill with blood during the relaxation phase; or reducing the ability of the valves of the heart to function properly. Any situation that increases the contraction or rate of contraction of the heart muscle can worsen these symptoms.
- Ischemic cardiomyopathy is caused by a narrowing of the arteries that supply the heart with blood. It makes the heart walls thin so they do not pump well.
- Restrictive cardiomyopathy is a group of disorders. The heart chambers are unable to fill with blood because the heart muscle is stiff. The most common causes of this type of cardiomyopathy are amyloidosis and scarring of the heart from an unknown cause.
- Peripartum cardiomyopathy occurs during pregnancy or in the first 5 months afterward.
Peripartum cardiomyopathy is a rare disorder in which a weakened heart is diagnosed within the last month of pregnancy or within 5 months after delivery, without other identifiable causes for dysfunction of the heart. The heart muscle becomes enlarged and weakened and cannot pump blood efficiently. Decreased heart function affects the lungs, liver, and other body systems.
When possible, the cause of cardiomyopathy is treated. Medicines and lifestyle changes are often needed to treat the symptoms of heart failure, angina and abnormal heart rhythms.
Procedures or surgeries may also be used, including:
- A defibrillator that sends an electrical pulse to stop life-threatening abnormal heart rhythms
- A pacemaker that treats a slow heart rate or helps the heart beat in a more coordinated fashion
- Coronary artery bypass (CABG) surgery or angioplasty that may improve blood flow to the damaged or weakened heart muscle
- Heart transplant that may be tried when all other treatments have failed
Partially and fully implantable mechanical heart pumps have been developed. These may be used for very severe cases. However, not all people need this advanced treatment.
The outlook depends on many different things, including:
- Cause and type of cardiomyopathy
- The severity of the heart problem
- How well the condition responds to treatment
Heart failure is most often a long-term (chronic) illness. It may get worse over time. Some people develop severe heart failure. In this case, medicines, surgery, and other treatments may no longer help.
People with certain types of cardiomyopathy are at risk for dangerous heart rhythm problems.
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