Each type of cardiomyopathy is associated with symptoms that correspond to the specific way in which the heart muscle is affected. Symptoms vary greatly among the types of cardiomyopathy, as well as from child to child of varying ages. Some may have mild or no symptoms, whereas others may have a more severe and progressive form of the disease.

Common signs and symptoms include:

  • Difficulty breathing or shortness of breath (dyspnea)
  • Chest discomfort or pressure (angina)
  • Irregular heartbeats (arrhythmia)
  • Rapid, pounding, or fluttering heartbeat (palpitations)
  • Light-headedness or dizziness (presyncope)
  • Fainting during physical activity (syncope)
  • Swelling in ankles, feet, legs, and abdomen (edema)
  • Daily fatigue and weakness
  • Exercise intolerance
  • Poor appetite and poor growth

When cardiomyopathy is secondary to another condition, such as Noonan syndrome, Pompe disease, fatty acid oxidation defect, or Barth syndrome, other physical abnormalities and symptoms can present early in life.

  • Low blood sugar (hypoglycemia)
  • Excess acidity in the blood (metabolic acidosis)
  • Neurological abnormalities (encephalogpathy)
  • Decreased muscle tone (hypotonia)

Complications with Advanced Disease

As the disease advances, there may be more serious complications and additional symptoms that appear:

  • Arrhythmia
  • Blood clots
  • Heart block
  • Pulmonary hypertension
  • Congestive heart failure

In the later stages of cardiomyopathy, arrhythmia and congestive heart failure are more likely. These complications need to be closely monitored because they can progress rapidly and become life-threatening.

For more information about signs and symptoms for each form of cardiomyopathy, please visit our Educational Materials page for downloadable inserts.