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.
- swelling of feet and ankles
- swelling of the abdomen
- pronounced neck veins
- loss of appetite
- shortness of breath, especially with activity
- shortness of breath which occurs after lying down for a while
- fatigue, weakness, faintness
- sensation of feeling the heart beat (palpitations)
- pulse may feel irregular or rapid
- decreased alertness or concentration
- low urine production
- need to urinate at night
Note: Symptoms of heart failure often develop gradually. Some chest pain may also be associated with this disease.
Signs and tests
Cardiomyopathy is usually discovered on examination and testing for the cause of heart failure. Tapping the area with the fingers and feeling the area may indicate enlargement of the heart. Listening to the chest with a stethoscope 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:
- Chest X-ray
- Chest CT scan
- Cardiac catheterization and coronary angiography
- 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.
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 cause should be treated. Some patients may require a specific type of pacemaker called a biventricular pacemaker. Any severe arrhythmias (abnormal heart rhythms) may need to be treated with an implantable defibrillator. A biventrical pacemaker with defibrillation capabilities may be needed in some casees.
A low-salt diet may be prescribed, and fluid may be restricted in some cases. Usually, regular activity may 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.
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.
- congestive heart failure
- pulmonary edema
- side effects of medications, including: o low blood pressure o lightheadedness and fainting o lupus reaction (a group of symptoms including a skin rash and arthritis) o headache o gastrointestinal upset
Calling your health care provider
Call your health care provider if symptoms indicate 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.
Modify risk factors that can be controlled by eating a generally well-balanced and nutritious diet, exercising to improve heart fitness, and avoiding or minimizing smoking and consumption of alcohol.
by Martin A. Harms, M.D.
All ArmMed Media material is provided for information only and is neither advice nor a substitute for proper medical care. Consult a qualified healthcare professional who understands your particular history for individual concerns.