Most tumors in the heart are caused by the spread (metastasis) of cancerous cells from other tumors. Tumors originating in the heart (primary tumors of the heart) are rare. Of the primary cardiac tumors, myxomas are the most common.

Women are more likely to be affected than men. Some atrial myxomas are inherited. Family history is a risk factor.

About 75% of cardiac myxomas are in the left atrium (atrial myxoma - left), and the rest are in the right atrium. Right atrial myxomas are sometimes associated with tricuspid stenosis and atrial fibrillation.

Right atrial myxomas rarely produce symptoms until they have grown to be at least 13 cm (about 5 inches) in diameter. Symptoms may occur at any time, although they typically accompany changes in body position. Symptoms may include the following:

• Shortness of breath (dyspnea)
  • on exertion
  • when lying down (orthopnea)
  • when asleep (paroxysmal nocturnal dyspnea)
• Dizziness
• Fatigue, tiredness
• Fainting (syncope)
• Sensation of feeling the heart beat (palpitations)
• Swelling of the feet, legs, or any body part (edema)
• Swelling of the abdomen
• Prominent veins in the neck

Other possible symptoms include:

• Chest pain or tightness
• Cough
• Fever
• Involuntary weight loss of more than 5% of body weight
• General discomfort (malaise)
• Joint pain
• Blueness (cyanosis) of skin
  • especially fingers
  • with cold or emotional stress
• Curvature of nails accompanied with soft tissue enlargement (clubbing) of fingers
• Awakening at night to urinate (nocturia)

You may have signs of right-sided heart failure such as swollen legs or abdomen or distended neck veins. Examination of the heart with a stethoscope (auscultation) may reveal a "tumor plop" (a sound related to movement of the tumor) or other abnormal sounds.

Some of the symptoms and signs in right atrial myxoma may be caused by tricuspid stenosis (an obstruction of the valve that separates the right atrium and the right ventricle).

Right atrial myxoma may show on these tests:

• Echocardiogram
• MRI of chest
• CT scan of chest
• Right ventriculogram
• Chest X-ray

An ECG may show atrial fibrillation. A CBC may show anemia and increased WBCs (white blood cells). The erythrocyte sedimentation rate (ESR) is increased.

The probable outcome is poor without treatment. Although a myxoma is a benign tumor, tumor cells can break off and travel through the bloodstream to the lungs, producing pulmonary embolism.

Local growth of the tumor can obstruct blood flow through the heart, producing the symptoms and signs of tricuspid stenosis.

• Arrhythmias
• Heart failure
• Pulmonary emboli