Cardiac myxoma


A myxoma is a rare benign tumor of the heart. Myxomas are the most common primary cardiac tumor in adults, and are most commonly found within the left atrium. Myxomas may also develop in the other heart chambers. The tumor is derived from multipotent mesenchymal cells.

Causes

Myxomas are the most common type of adult primary heart tumor. Most myxomas arise sporadically, and only about 10% are thought to arise due to inheritance.
About 10% of myxomas are inherited, as in Carney syndrome. 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 than other myxomas. Other abnormalities are observed in people with Carney syndrome include skin myxomas, pigmentation, endocrine hyperactivity, schwannomas and epithelioid blue nevi. Myxomas are more common in women than men.

Signs and symptoms

Symptoms may occur at any time, but most often they accompany a change of body position. Pedunculated myxomas can have a "wrecking ball effect", as they lead to stasis and may eventually embolize themselves. Symptoms may include:
The symptoms and signs of left atrial myxomas often mimic mitral stenosis.
General symptoms may also be present, such as:
These general symptoms may also mimic those of infective endocarditis.

Complications

A doctor will listen to the heart with stethoscope. A "tumor plop", abnormal heart sounds, or a murmur similar to the mid-diastolic rumble of mitral stenosis may be heard. These sounds may change when the patient changes position.
Right atrial myxomas rarely produce symptoms until they have grown to be at least 13 cm wide.
Tests may include:
Blood tests:
A FBC may show anemia and increased WBCs. The erythrocyte sedimentation rate is usually increased.

Treatment

The tumor must be surgically removed. 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.

Prognosis

Although a myxoma is not malignant with risk of metastasis, complications are common. Untreated, a myxoma can lead to an embolism. Myxoma fragments can move to the brain, eye, or limbs.
If the tumor continues to enlarge inside the heart, it can block blood flow through the mitral valve and cause symptoms of mitral stenosis or mitral regurgitation. This may require emergency surgery to prevent sudden death.