Dilated cardiomyopathy is a group of disorders in which the heart muscle is weakened and cannot pump blood efficiently. Decreased heart function affects the lungs, liver, and other body systems.
Causes, incidence, and risk factors
The causes of cardiomyopathy are multiple and may include nutritional deficiencies, valvular heart disease anemia , stress , viral infections (rare), alcoholism ( alcoholic cardiomyopathy ), coronary artery disease , and others. In some cases, no cause can be identified ( idiopathic cardiomyopathy ).
Enlargement of the heart muscle (dilated cardiomyopathy) is the most common type of cardiomyopathy. Restrictive cardiomyopathy is another type that occurs when there is damage to the heart and scarring (fibrosis) or deposits develop in the heart muscle.
Some risk factors include obesity , having a personal or family history of cardiac disorders, such as myocarditis and alcoholism.
Dilated cardiomyopathy occurs in approximately 2 out of 100 people. It can affect all ages and both sexes, but is most common in adult men.
Signs and tests
Cardiomyopathy is usually discovered on examination and testing for the cause of heart failure . Tapping the area with the fingers ( percussion ) and feeling the area ( palpation ) may indicate enlargement of the heart. Listening to the chest with a stethoscope ( auscultation ) reveals lung crackles, heart murmur, or other abnormal sounds. The liver may be enlarged. Neck veins may be distended.
Heart enlargement, congestion of the lungs, decreased movement/functioning of the heart, or heart failure may show on:
an echocardiogram :
a chest X-ray
a chest CT scan
a cardiac catheterization and coronary angiography
a nuclear heart scan ( MUGA , RNV ) An ECG may show conduction disturbances and/or arrhythmias , and may indicate enlargement of the ventricles. Heart biopsy may be helpful to distinguish dilated cardiomyopathy from other diseases. Lab tests vary depending on the suspected cause.
Treatment
Hospitalization may be required until acute symptoms subside. Treatment is focused on relief of symptoms. Digitalis, vasodilators (drugs that dilate blood vessels), ACE-inhibitors, diuretics (water pills), nutritional supplements, and other medications may be prescribed to reduce symptoms. The underlying disorder (cause) should be treated. Associated severe arrhythmias (abnormal heart rhythms) may need to be treated with an implantable defibrillator.
A low-salt diet may be prescribed, and fluid may be restricted in some cases. Activity may often continue as tolerated. A heart transplant may be considered if the heart function is very poor. Daily monitoring of body weight may be advised. Weight gain of 3 or 4 pounds or more over 1 or 2 days may indicate fluid accumulation. Smoking and drinking alcohol may worsen the symptoms.
Expectations (prognosis)
The outcome varies. Some affected individuals remain in a stable condition for long periods, some deteriorate gradually, and some deteriorate rapidly. Cardiomyopathy is correctable only if the underlying disease can be cured. It is incurable if the underlying disease cannot be corrected.
Calling your health care provider
Call your health care provider if symptoms indicating cardiomyopathy may be present.
Go to the emergency room or call the local emergency number (such as 911) if chest pain , palpitations , faintness , or other new or unexplained symptoms develop.
Prevention
Modify risk factors that can be controlled by eating a generally well-balanced and nutritious diet, exercising to improve cardiovascular fitness, and avoiding or minimizing smoking and consumption of alcohol.