A myxoma (New Latin from Greek 'muxa' for

mucus Mucus ( ) is a slippery aqueous secretion produced by, and covering, mucous membranes. It is typically produced from cells found in mucous glands, although it may also originate from mixed glands, which contain both serous and mucous cells. It ...

) is a myxoid tumor of primitive connective tissue. It is most commonly found in the heart (and is the most common primary tumor of the

heart The heart is a muscular organ in most animals. This organ pumps blood through the blood vessels of the circulatory system. The pumped blood carries oxygen and nutrients to the body, while carrying metabolic waste such as carbon dioxide to t ...

in adults) but can also occur in other locations.

Types

Table below: 1.SMA, smooth muscle

actin Actin is a family of globular multi-functional proteins that form microfilaments in the cytoskeleton, and the thin filaments in muscle fibrils. It is found in essentially all eukaryotic cells, where it may be present at a concentration of ov ...

. 2.MSA, muscle-specific

. 3.EMA,

epithelial membrane antigen Mucin short variant S1, also called polymorphic epithelial mucin (PEM) or epithelial membrane antigen (EMA), is a mucin encoded by the ''MUC1'' gene in humans. Mucin short variant S1 is a glycoprotein with extensive O-linked glycosylation of its e ...

Symptoms and signs

Symptoms associated with cardiac myxomas are typically due to the effect of the mass of the tumor obstructing the normal flow of blood within the chambers of the heart. Because pedunculated myxomas are somewhat mobile, symptoms may only occur when the patient is in a particular position. Some symptoms of myxoma may be associated with the release of

interleukin 6 Interleukin 6 (IL-6) is an interleukin that acts as both a pro-inflammatory cytokine and an anti-inflammatory myokine. In humans, it is encoded by the ''IL6'' gene. In addition, osteoblasts secrete IL-6 to stimulate osteoclast formation. Smooth ...

(IL-6) by the myxoma. High levels of IL-6 may be associated with a higher risk of

embolism An embolism is the lodging of an embolus, a blockage-causing piece of material, inside a blood vessel. The embolus may be a blood clot (thrombus), a fat globule (fat embolism), a bubble of air or other gas ( gas embolism), amniotic fluid (am ...

of the myxoma. Symptoms of a cardiac myxoma include: *

Dyspnea Shortness of breath (SOB), also medically known as dyspnea (in AmE) or dyspnoea (in BrE), is an uncomfortable feeling of not being able to breathe well enough. The American Thoracic Society defines it as "a subjective experience of breathing di ...

on exertion *

Paroxysmal nocturnal dyspnea Paroxysmal nocturnal dyspnea or paroxysmal nocturnal dyspnoea (PND) is an attack of severe shortness of breath and coughing that generally occurs at night. It usually awakens the person from sleep, and may be quite frightening. PND, as well as simp ...

Fever Fever, also referred to as pyrexia, is defined as having a temperature above the normal range due to an increase in the body's temperature set point. There is not a single agreed-upon upper limit for normal temperature with sources using val ...

Weight loss Weight loss, in the context of medicine, health, or physical fitness, refers to a reduction of the total body mass, by a mean loss of fluid, body fat ( adipose tissue), or lean mass (namely bone mineral deposits, muscle, tendon, and other co ...

(see

cachexia Cachexia () is a complex syndrome associated with an underlying illness, causing ongoing muscle loss that is not entirely reversed with nutritional supplementation. A range of diseases can cause cachexia, most commonly cancer, congestive heart ...

) * Lightheadedness or syncope (Loss of consciousness) *

Hemoptysis Hemoptysis is the coughing up of blood or blood-stained mucus from the bronchi, larynx, trachea, or lungs. In other words, it is the airway bleeding. This can occur with lung cancer, infections such as tuberculosis, bronchitis, or pneumonia, a ...

* Sudden death *

Tachycardia Tachycardia, also called tachyarrhythmia, is a heart rate that exceeds the normal resting rate. In general, a resting heart rate over 100 beats per minute is accepted as tachycardia in adults. Heart rates above the resting rate may be normal ( ...

or milder heartrate, i.e. 75 - 100 cycl/min

Location

Ocular myxoma

Myxoma is a rare, benign stromal tumor of mesenchymal origin often confused with other conjunctival stromal tumors. Conjunctival myxomas are thought to originate in Tenon's capsule and can masquerade as conjunctival lymphoma, lymphangioma, ocular surface squamous neoplasia (OSSN), or amelanotic melanoma. * Atrial myxoma * Cutaneous myxoma *

Odontogenic myxoma The odontogenic myxoma is an uncommon benign odontogenic tumor arising from embryonic connective tissue associated with tooth formation.Sapp, J. Philip., Lewis R. Eversole, and George P. Wysocki. Contemporary Oral and Maxillofacial Pathology. 2nd ...

Atrial myxoma

Myxomas are usually located in either the left or

right atrium The atrium ( la, ātrium, , entry hall) is one of two upper chambers in the heart that receives blood from the circulatory system. The blood in the atria is pumped into the heart ventricles through the atrioventricular valves. There are two at ...

of the heart; about 86 percent occur in the

left atrium The atrium ( la, ātrium, , entry hall) is one of two upper chambers in the heart that receives blood from the circulatory system. The blood in the atria is pumped into the heart ventricles through the atrioventricular valves. There are two at ...

. Myxomas are typically

pedunculated A peduncle is an elongated stalk of tissue. Sessility is the state of not having a peduncle; a sessile mass or structure lacks a stalk. In medicine, a mass such as a cyst or polyp is said to be ''pedunculated'' if it is supported by a peduncle ...

, with a stalk that is attached to the

interatrial septum The interatrial septum is the wall of tissue that separates the right and left atria of the heart. Structure The interatrial septum is a that lies between the left atrium and right atrium of the human heart. The interatrial septum lies at angl ...

. The most common location for attachment of the stalk is the fossa ovalis region of the interatrial septum. An atrial myxoma may create an extra

heart sound Heart sounds are the noises generated by the beating heart and the resultant flow of blood through it. Specifically, the sounds reflect the turbulence created when the heart valves snap shut. In cardiac auscultation, an examiner may use a stet ...

, audible to auscultation just after S2. It is most seen on echocardiography, as a pedunculated mass that is heterogeneous in appearance. A left atrial myxoma will cause an increase in pulmonary capillary wedge pressure. The differential diagnosis include other cardiac tumors such as

lipoma A lipoma is a benign tumor made of fat tissue. They are generally soft to the touch, movable, and painless. They usually occur just under the skin, but occasionally may be deeper. Most are less than in size. Common locations include upper back, ...

s and

rhabdomyoma A rhabdomyoma is a benign tumor of striated muscle. Rhabdomyomas may be either "cardiac" or "extra cardiac" (occurring outside the heart). Extracardiac forms of rhabdomyoma are sub classified into three distinct types: adult type, fetal type, and ...

s (and rarely

teratoma A teratoma is a tumor made up of several different types of tissue, such as hair, muscle, teeth, or bone. Teratomata typically form in the ovary, testicle, or coccyx. Symptoms Symptoms may be minimal if the tumor is small. A testicular ter ...

s). These other tumors of the heart are typically not pedunculated, however, and are more likely to infiltrate the muscle of the heart. Cardiac magnetic resonance imaging (MRI) can help non-invasively diagnose cardiac tumors. However, diagnosis usually requires examination of a tissue sample by a

pathologist Pathology is the study of the causes and effects of disease or injury. The word ''pathology'' also refers to the study of disease in general, incorporating a wide range of biology research fields and medical practices. However, when used in t ...

Treatment

Myxomas are usually removed surgically. The surgeon removes the myxoma, along with at least 5 surrounding millimeters of atrial septum. The septum is then repaired, using material from the

pericardium The pericardium, also called pericardial sac, is a double-walled sac containing the heart and the roots of the great vessels. It has two layers, an outer layer made of strong connective tissue (fibrous pericardium), and an inner layer made o ...

Epidemiology

Cardiac myxomas predominantly appear in females in their 30s to 40s. Myxomas are the most common primary cardiac tumor affecting adults, accounting for one quarter to half of primary cardiac tumors seen in clinical practice.

References

External links

*
Myxomatous degeneration at Wikidoc
{{Heart and thymus neoplasia Heart neoplasia Connective/soft tissue tumors and sarcomas