Symptoms:

• Heart failure
• Shock
• Swelling of feet and ankles (in adults)
• Swelling of the abdomen (in adults)
• Pronounced neck veins
• Loss of appetite
• Shortness of breath, especially with activity
• Shortness of breath occurring after lying down for awhile ,or in infants while feeding
• Fatigue, weakness, faintness
• Sensation of feeling the heart beat (palpitations)
• Pulse may feel irregular or rapid
• Decreased alertness or concentration
• Cough
• Low urine production
• Need to urinate at night (in adults)
• Failure to thrive (in children)
• Alström syndrome

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.

Children will have poor growth, pale skin, difficulty feeding, and weak pulses in the legs and arms.

Heart enlargement, congestion of the lungs, decreased movement/functioning of the heart, or heart failure may show on:

• Echocardiogram
• Chest x-ray
• Chest CT scan or MRI of the heart
• Cardiac catheterization and coronary angiography
• Nuclear heart scan (MUGA, RNV)

An ECG may show conduction disturbances or arrhythmias, including tachycardia, 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.