Atrial myxomaCardiac tumor - myxoma; Heart tumor - myxoma
An atrial myxoma is a noncancerous tumor in the upper left or right side of the heart. It most often grows on the wall that separates the two sides of the heart. This wall is called the atrial septum.
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 such as myxomas are rare. About 75% of myxomas occur in the left atrium of the heart. They most often begin in the wall that divides the two upper chambers of the heart. They can occur in other intra-cardiac sites as well. Atrial myxomas are sometimes linked with valve obstruction stenosis and atrial fibrillation.
Left atrial myxoma
A myxoma is a benign tumor in the heart most commonly found in the left atrium. About 75% of myxomas are in the left atrium, usually beginning in the wall that divides the lower chambers of the heart (ventricles) and growing into the atrium. Treatment is necessary to avoid metastasis and the formation of clots. In addition, untreated growth of the tumor can obstruct blood flow through the heart. Myxomas are curable with surgical removal.
Right atrial myxoma
A myxoma is a benign tumor in the heart. Right atrial myxomas occur less frequently than left atrial myxomas. Treatment is necessary to avoid metastasis and the formation of clots. In addition, untreated growth of the tumor can obstruct blood flow through the heart. Myxomas are curable with surgical removal.
Myxomas are more common in women. About 1 in 10 myxomas are passed down through families (inherited). These 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.
Many myxomas will not cause symptoms. These are often discovered when an imaging study (echocardiogram, MRI, CT) is done for another reason.
Symptoms may occur at any time, but often they go along with a change in body position.
Symptoms of a myxoma may include:
The symptoms and signs of left atrial myxomas often mimic mitral stenosis (narrowing of the valve between the left atrium and the left ventricle). Right atrial myxomas rarely produce symptoms until they have grown to be quite large (5 inches wide, or 13 cm).
Other symptoms may include:
Exams and Tests
The health care provider will perform a physical exam and listen to your heart through a stethoscope. Abnormal heart sounds or a murmur may be heard. These sounds may change when you change body position.
Imaging tests may include:
You may also need blood tests including:
Surgery is needed to remove the tumor, especially if it is causing heart failure symptoms or an embolism.
Untreated, a myxoma can lead to an embolism (tumor cells or a clot that breaks off and travels in the bloodstream). This can lead to a blockage of blood flow. Pieces of the tumor can move to the brain, eye, or limbs.
If the tumor grows inside the heart, it can block blood flow, causing symptoms of obstruction.
Complications may include:
Lenihan DJ, Yusuf SW, Shah A. Tumors affecting the cardiovascular system. In: Zipes DP, Libby P, Bonow RO, Mann DL, Tomaselli GF, Braunwald E, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 11th ed. Philadelphia, PA: Elsevier; 2019:chap 95.
Tazelaar HD, Maleszewski JJ. Tumors of the heart and pericardium. In: Fletcher CDM, ed. Diagnostic Histopathology of Tumors. 5th ed. Philadelphia, PA: Elsevier; 2021:chap 2.