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Related to myxoma: Atrial myxoma




A myxoma is a rare, usually noncancerous, primary tumor (a new growth of tissue) of the heart. It is the most common of all benign heart tumors.


Myxoma is an intracardiac tumor; it is found inside the heart. Seventy five percent of all myxomas are found in the left atrium, and almost all other myxomas are found in the right atrium. It is very rare for a myxoma to be found in either of the ventricles. The tumor takes one of two general shapes: a round, firm mass, or an irregular shaped, soft, gelatinous mass. They are attached to the endocardium, the inside lining of the heart. The cells that make up the tumor are spindle-shaped cells and are embedded in a matrix rich in mucopolysaccharides (a group of carbohydrates). Myxomas may contain calcium, which shows up on x rays. The tumor gets its blood supply from capillaries that bring blood from the heart to the tumor. Thrombi (blood clots) may be attached to the outside of the myxoma.
There are three major syndromes linked to myxomas: embolic events, obstruction of blood flow, and constitutional syndromes. Embolic events happen when fragments of the tumor, or the thrombi attached to the outside of the tumor, are released and enter the blood stream. Gelatinous myxomas are more likely to embolize than the more firm form of this tumor.
Myxomas may also obstruct blood flow in the heart, usually at a heart valve. The mitral valve is the heart valve most commonly affected. Blood flow restrictions can lead to pulmonary congestion and heart valve disease. Embolization can lead to severe consequences. In cases of left atrial myxoma, 40-50% of patients experience embolization. Emboli usually end up in the brain, kidneys, and extremities.
The third syndrome linked to myxomas are called constitutional syndromes, nonspecific symptoms caused by the myxoma.

Causes and symptoms

There is no known causative agent for myxoma. The main symptoms, if any, produced by myxoma are generic and not specific. These include fever, weight loss, anemia, elevated white blood cell (WBC) count, decreased platelet count and Raynaud's phenomenon. Most patients with myxoma are between 30-60 years of age.


Diagnosis is made following a suspicion that a myxoma might be present, and can usually be confirmed by echocardiogram


Surgery is used to remove the tumor. Myxomas can regrow if they are not completely removed. The survival rate for this operation is excellent.


Successful removal of the tumor rids the patient of this disease. Emboli from a myxoma may survive in other areas of the body. However, there is no evidence that myxoma is truly metastatic (able to transfer disease from one area to another), causing tumors in other areas of the body.

Key terms

Embolus — A piece of tissue, blood clot, etc. that travels through the blood system and can lodge in smaller blood vessels anywhere in the body.
Metastasis — The spread of a cancer or infectious agent from the site of origin to other areas of the body.
Raynaud's phenomenon — Intermittant ischemia (deficient blood flow) of the fingers or toes, sometimes also affecting the ears and nose.



"Myxoma, Intracardiac." OMIM Home Page, Online Mendelian Inheritance in Man.


a tumor composed of primitive connective tissue cells and stroma resembling mesenchyma. adj., adj myxo´matous.


A benign neoplasm derived from connective tissue, consisting chiefly of polyhedral and stellate cells that are loosely embedded in a soft mucoid matrix, thereby resembling primitive mesenchymal tissue; occurs frequently intramuscularly (where it may be mistaken for a sarcoma), also in the jaw bones, and encysted in the skin (focal mucinosis and dorsal wrist ganglion).
[myxo- + G. -ōma, tumor]


/myx·o·ma/ (mik-so´mah) pl. myxomas, myxo´mata   a benign tumor composed of primitive connective tissue cells and stroma resembling mesenchyme.


n. pl. myxo·mas or myxo·mata (-mə-tə)
A benign tumor, most often found in the heart, composed of connective tissue embedded in mucus.

myx·o′ma·tous (-sō′mə-təs, -sŏm′ə-) adj.


Etymology: Gk, myxa + oma, tumor
a neoplasm of the connective tissue, characteristically composed of stellate cells in a loose mucoid matrix crossed by delicate reticulum fibers. These tumors may grow to enormous size and may occur under the skin but are also found in bones, the genitourinary tract, and the retroperitoneal area. myxomatous, adj.


A benign neoplasm derived from connective tissue, consisting of polyhedral and stellate cells embedded in a soft mucoid matrix; occurs in bone, skin, and muscle; when arising from cardiac muscle may encroach on the cavity of an atrium.
[myxo- + G. -ōma, tumor]


A rare, benign, jelly-like tumour consisting of soft mucoid material, mainly hyaluronic acid. Myxomas may affect muscles, especially in the shoulder and thigh and sometimes occur within one of the chambers of the heart. A myxoma in this situation may cause blood clot EMBOLI or may interfere with the normal flow of blood. If necessary, a cardiac myxoma may be removed surgically.


Benign neoplasm derived from connective tissue, found intramuscularly and in jaw bones.
[myxo- + G. -ōma, tumor]

myxoma (miksō´mə),

n a benign tumor composed of fibroblastic cells that have reverted to embryonic growth and produce a mucoid matrix containing widely dispersed stellate cells that have multipolar processes. myxoma, odontogenic, n a new growth of soft tissue, gelatinous in appearance, originating from the mesenchymal tissue of the tooth. The growth may invade tissues surrounding the region, and it does not metastasize or provide any bodily function.


a tumor composed of primitive connective tissue cells and stroma resembling mesenchyme.

heart valve myxoma
developmental abnormality caused by persistence of embryonic myxomatous tissue in the endocardial cushions.
myxoma virus
a poxvirus in the genus Leporipoxvirus; the cause of myxomatosis of rabbits.
References in periodicals archive ?
In the case described here, obstruction of the mitral valve by the myxoma may have provoked syncope and features of left ventricular failure.
Following discussion by the multi-disciplinary team, a working diagnosis of sinonasal myxoma was agreed upon with recommendation for a left Caldwell-Luc antrostomy, leading to extensive excision of the mass.
With these macroscopic, microscopic, and immunohistochemical findings, the final histopathological diagnosis was primary renal myxoma.
Dr Sadasivan explained that the only way to detect Myxoma was through cardiological tests.
Alter Melody's death, her family brought suit against both physicians and their group alleging that the direct and proximate cause of Melody's death was that the physicians and their group misdiagnosed Melody's condition which allegedly was atrial myxoma.
In fact, avoiding brain emboli is one of the major reasons for myxoma resection.
The European rabbit, on the other hand, can be devastated by the myxoma virus.
22) An example of this involved the natural selection of rabbits resistant to the virulent myxoma virus, which was documented during several epidemics deliberately induced to control the Australian rabbit population.
Rabbit control was achieved in the 1950s using the myxoma virus (a world first: successful biological control of a vertebrate pest) and again in the 1990s, with calicivirus.
When the myxoma virus was deliberately introduced as a control measure in Australia in 1950, rabbit populations were decimated.
While a transplant may have cured the myxoma, he explained, "A transplant comes with the possibilities of organ rejection, the need to take antirejection drugs, and the 50 percent average 10-year survival rate.
McFadden and his colleagues have instead pursued studies of myxoma virus, a variola relative that infects rabbits.