Cardiomyopathy

Causes

In many cases, the exact cause is not known. Possible causes include:

Dilated

The cause of the initial damage is often not found, but may include:

• Coronary artery disease (CAD) with decreased blood flow to your heart
• Infections, usually viral
• Chronic exposure to toxins, including alcohol and some chemotherapy drugs
• A rare complication of pregnancy or childbirth (probably immune-related)
• Rarely, other illnesses, including rheumatoid arthritis, diabetes, or thyroid disease

Hypertrophic

Causes may include:

• Inherited—sometimes present at birth but often developing in teens
• Aging, associated with hypertension

Restrictive

Causes are usually related to another condition, such as:

• Amyloidosis—protein fibers collect in the heart
• Sarcoidosis—small inflammatory masses (granulomas) form in many organs
• Hemochromatosis—too much iron in the body

Risk Factors

Factors that increase your chance of getting cardiomyopathy include:

• Family members with cardiomyopathy
• Alcohol use disorder
• Obesity
• Diabetes
• High blood pressure
• CAD
• Certain drugs

Symptoms

Symptoms vary depending on the type of cardiomyopathy and its severity.

Cardiomyopathy leads to heart failure and the following symptoms:

• Fatigue
• Weakness
• Shortness of breath, often worse when lying down or with activity
• Cough
• Swelling in feet or legs
• Chest pain
• Irregular heart rhythm

Diagnosis

You will be asked about your symptoms and medical history. A physical exam will be done. A stethoscope will be used to listen to your heart. Cardiomyopathies often produce heart murmurs and other abnormal sounds.

Images of your chest may be needed. This can be done with:

• Chest x-ray
• Echocardiogram

Tests may be done to determine how your heart functions. These can be done with:

• Electrocardiogram (ECG)
• Cardiac catheterization

Your bodily fluids and tissue may need to be tested. This can be done with:

• Blood tests
• Heart biopsy

Treatment

Heart failure may be due to blockages in the arteries. Treatments to relieve these blockages include angioplasty, stent placement, and coronary artery bypass surgery. These may lead to improved heart function and symptoms. For certain genetic causes, other treatments may also improve heart function. For many people, treatment is aimed at relieving symptoms and preventing further damage.

Lifestyle Modification

Changes to eliminate anything that adds to the disease or worsens symptoms:

• Avoid alcohol.
• If you are overweight, talk to your doctor about ways to help you lose weight.
• Eat a low-fat diet to reduce the risk and extent of coronary artery disease.
• Limit salt intake to reduce fluid retention.
• Follow your doctor's advice about exercise. You may need to limit physical activity.

Medications

Medications may include:

• Diuretics—to remove extra fluid
• Angiotensin-converting enzyme (ACE) inhibitors—to relax blood vessels, lower blood pressure, and decrease the heart's workload
• Angiotensin receptor blockers—similar to ACE inhibitors
• Hydralazine and isosorbide dinitrate—may be used with ACE inhibitors
• Digitalis—to slow and regulate heart rate and slightly increase its force of contractions
• Beta-blockers—to slow the heart and limit disease progression
• Spironolactone—to improve the outcome in people with dilated cardiomyopathy and advanced symptoms

Surgery

Surgical options include:

• A pacemaker may be implanted to improve heart rate and pattern.
• For people with hypertrophic disease, doctors may remove part of the thickened wall that separates the heart's chambers. Surgery may be needed to replace a heart valve. Another option is alcohol septal ablation. This procedure reduces symptoms and improves how the heart functions.
• For those with life-threatening, irregular heart rhythms, a cardioverter defibrillator may need to be implanted.
• A heart transplant may be possible for otherwise healthy people who do not respond to medical treatment. Candidates often wait a long time for a new heart. Those waiting may temporarily receive a ventricular assist device. This is a mechanical pump that takes over some or most of the heart's pumping function.

Prevention

Actively treat hypertension, coronary artery diseases, and their risk factors. This is the best way to prevent most cases of cardiomyopathy. However, other less common causes are not preventable. If you have a family history of the disease, ask your doctor about screening tests. Do this especially before starting an intense exercise program.