Dilated Cardiomyopathy

What is Dilated Cardiomyopathy?

Dilated cardiomyopathy - also called congestive cardiomyopathy results from extensively damaged myocardial muscle fibers. It interferes with myocardial metabolism and grossly dilates every heart chamber, giving the heart a globular shape. When hypertrophy coexists with dilated cardiomyopathy, the heart ejects blood less efficiently than normal and a large volume of blood remains in the left ventricle after systole, causing signs of heart failure.

Dilated cardiomyopathy most commonly affects middle-aged men but can occur in any age-group. Because it isn't usually diagnosed until the advanced stages, the prognosis is generally poor. Most patients, especially those over age 55, die within 2 years of symptom onset.

Causes of Dilated Cardiomyopathy

There are many causes of dilated cardiomyopathy. They may include nutritional deficiencies, valvular heart disease, anemia, stress, viral infections (rare), alcoholism (alcoholic cardiomyopathy), and coronary artery disease.

Dilated cardiomyopathy occurs in an estimated 2 out of 100 people. It can affect anyone of any age, although it is most common in adult men.

Risk factors include obesity, cocaine use, a personal or family history of cardiac disorders (such as myocarditis), and alcoholism.

Signs & Symptoms of Dilated Cardiomyopathy

Sometimes dilated cardiomyopathy does not cause any symptoms. At other times, you may feel symptoms most often associated with the common cold or flu: chills, fever, overall aches, and fatigue.

When your heart becomes very enlarged, you will feel symptoms. These symptoms include chest pain, extreme tiredness, shortness of breath, and swelling of the legs and ankles. All of these are the early signs of heart failure.

Diagnostic Tests

No single test confirms dilated cardiomyopathy. Diagnosis requires elimination of other possible causes of heart failure and arrhythmias.

• Chest X-rays demonstrate moderate to marked cardiomegaly usually affecting all heart chambers, along with pulmonary congestion, pulmonary venous hypertension, and pleural effusion. Pericardial effusion may appear as a waterbottle shape.
• Cardiac catheterization can show left ventricular dilation and dysfunction, elevated left ventricular and (in some instances) right ventricular filling pressures, and diminished cardiac output.
• Gallium scans may identify patients with dilated cardiomyopathy and myocarditis.
• An electrocardiogram (ECG or EKG) can show areas of your heart that are damaged.
• Transvenous endomyocardial biopsy may be useful in some patients to determine the underlying disorder, such as amyloidosis or myocarditis.

Treatment

In dilated cardiomyopathy, the goal of treatment is to correct the underlying causes and to improve the heart's pumping ability with digitalis glycosides, diuretics, oxygen, anticoagulants, vasodilators, and a low-sodium diet supplemented by vitamin therapy.Antiarrhythmics may be used to treat arrhythmias. If cardiomyopathy is due to alcoholism, ingestion of alcohol must be stopped. A woman of childbearing age snould avoid pregnancy.

Therapy may also include prolonged bed rest and selective use of corticosteroids, particularly when myocardial inflammation is present.

Vasodilators reduce preload and afterload, thereby. decreasing congestion and increasing cardiac output. Acute heart failure necessitates vasodilation with nitroprusside I.V. or nitroglycerin I.V. Long-term treatment may include prazosin, hydralazine, isosorbide dinitrate and, if the patient is on prolonged bed rest,anticoagulants. Dopamine, dobutamine, and amrinone may be useful during the acute stage.

When these treatments fail, therapy may require heart transplantation for carefully selected patients.

Cardiomyoplasty may be used for those who aren't cadidates for transplants and who are symptomatic at rest. In cardiomyoplasty, the latissimus dorsi musle is wrapped around the ventricle, assisting the ventricle to effectively pump blood. A cardiomyostimulator delivers bursts of electrical impulses during systole to contract the muscle.

Prevention Tips

Eat a well-balanced and nutritious diet, exercise to improve heart fitness, stop smoking, and minimize alcohol consumption.