Symptoms of restrictive cardiomyopathy are usually the same as those typically seen in heart failure and include:

• Weight gain caused by water retention and fluid buildup (edema), especially in the legs, ankles, and feet.
• Abdominal swelling, tenderness, or pain, which may result from the buildup of fluid in the abdomen (ascites) and blood that backs up in the liver.
• Difficulty breathing during normal activities or exercise that did not cause breathing problems before.
• A dry, hacking cough, especially when lying down. At night, you may wake up coughing with a rapid heart rate and a feeling of being suffocated (paroxysmal nocturnal dyspnea).
• Dizziness, fainting, or feeling tired or weak.
• Heart palpitations.
• Increased urination at night.

Sudden heart failure can develop, causing congestion and rapid fluid buildup in the lungs (pulmonary edema). This is an emergency medical situation and requires immediate care. Symptoms develop quickly and include:

• Severe shortness of breath.
• An irregular or rapid heartbeat.
• Coughing up foamy, pink mucus.

Sudden heart failure is different from gradual heart failure and may be triggered by:

• Drinking too many fluids.
• Eating too much salt.
• Not following directions for taking medicines.
• An irregular or rapid heartbeat that comes on suddenly.
• Having a heart attack.

Complications of restrictive cardiomyopathy can also be very serious. They include:

• A blood clot that develops in the heart. The clot can break loose, travel through the bloodstream, become lodged in a blood vessel, and block blood supply to:
  • The brain, resulting in a stroke.
  • The heart, causing a heart attack.
  • The lungs, causing a pulmonary embolism.
  • A limb or elsewhere in the body, possibly causing a loss of circulation and tissue damage.
• Episodes of rapid, abnormal heart rhythms (arrhythmia), especially atrial fibrillation.
• Sudden cardiac death.