Atrial myxoma

An atrial myxoma is a noncancerous tumor in the upper left or right side of the heart. It grows on the wall that separates the two sides of the heart. This wall is called the atrial septum.

Causes
A myxoma is a primary heart (cardiac) tumor. This means that the tumor started within the heart. Most heart tumors start somewhere else.

Primary cardiac tumors are rare. Myxomas are the most common type of these rare tumors. About 75% of myxomas occur in the left atrium of the heart, usually beginning in the wall that divides the two upper chambers of the heart. The rest are in the right atrium. Right atrial myxomas are sometimes associated with tricuspid stenosis and atrial fibrillation.

Myxomas are more common in women. About 1 in 10 myxomas are passed down through families (inherited). Such tumors are called familial myxomas. They tend to occur in more than one part of the heart at a time, and often cause symptoms at a younger age.

Symptoms
Symptoms may occur at any time, but most often they go along with a change in body position.

Symptoms of a myxoma may include:

Breathing difficulty when lying flat
Breathing difficulty when asleep
Chest pain or tightness
Dizziness
Fainting
Sensation of feeling your heart beat (palpitations)
Shortness of breath with activity
The symptoms and signs of left atrial myxomas often mimic mitral stenosis. Right atrial myxomas rarely produce symptoms until they have grown to be at least 5 inches wide.

Other symptoms may include:

Blueness of skin, especially the fingers (Raynaud's phenomenon)
Cough
Curvature of nails accompanied with soft tissue swelling (clubbing) of the fingers
Fever
Fingers that change color upon pressure or with cold or stress
General discomfort (malaise)
Losing weight without trying
Joint pain
Swelling - any part of the body
Exams and Tests
The doctor or nurse will perform a physical exam and listen to your heart using a tool called a stethoscope. Abnormal heart sounds or a murmur may be heard. These sounds may change when you change body position.

Imaging tests may include:

Chest x-ray
CT scan of chest
ECG
Echocardiogram
Doppler study
Heart MRI
Left heart angiography
Right heart angiography
Blood tests:

A complete blood count may show anemia and increased white blood cells. The erythrocyte sedimentation rate (ESR) is increased.

Treatment
Surgery is needed to remove the tumor. Some patients will also need their mitral valve replaced. This can be done during the same surgery.

Myxomas may come back if surgery did not remove all of the tumor cells.

Outlook (Prognosis)
Although a myxoma is not cancer, complications are common.

Untreated, a myxoma can lead to an embolism (tumor cells breaking off and traveling with the bloodstream), which can block blood flow or cause the tumor to grow in another part of the body. Pieces of the tumor can move to the brain, eye, or limbs.

If the tumor grows inside the heart, it can block blood flow. This may require emergency surgery to prevent sudden death.

Possible Complications
Arrhythmias
Pulmonary edema
Peripheral emboli
Spread (metastasis) of the tumor
Blockage of the mitral heart valve
References
McManus B. Primary tumors of the heart. In: Bonow RO, Mann DL, Zipes DP, Libby P, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 9th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap74.

McKenna W. Diseases of the myocardium and endocardium. In:Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, PA: Saunders Elsevier; 2011:chap 60.

Update Date: 6/7/2012
Updated by: Glenn Gandelman, MD, MPH, FACC Assistant Clinical Professor of Medicine at New York Medical College, and in private practice specializing in cardiovascular disease in Greenwich, CT. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.