Half of all primary (arising in the heart) heart tumors Overview of Heart Tumors A tumor is any type of abnormal growth, whether cancerous (malignant) or noncancerous (benign). Tumors in the heart may be Primary (noncancerous or cancerous) Metastatic (always cancerous) Primary... read more are myxomas. Three fourths of myxomas occur in the left atrium, the chamber of the heart that receives oxygen-rich blood from the lungs. Myxomas usually develop in women, typically between the ages of 40 and 60.
Some uncommon types of myxomas run in families. These hereditary myxomas (part of Carney complex, a syndrome of various noncancerous tumors) usually develop in young men in their mid-20s, and they can occur in one or more of any of the chambers of the heart.
How a Myxoma Can Block Blood Flow in the Heart
Myxomas in the left atrium often grow from a stalk and swing freely with the flow of blood, as a tetherball does. As they swing, they may move in and out of the nearby mitral valve, the valve that opens from the left atrium into the left ventricle. This swinging motion may plug and unplug the valve over and over again, so that blood flow stops and starts intermittently.
When they stand, people with a myxoma in the left atrium may feel short of breath or may faint. When a person is standing, the force of gravity pulls the myxoma into the opening of the mitral valve, blocking blood flow through the heart. This blockage causes a transient drop in blood pressure because less blood is able to be pumped from the heart. Lying down typically causes the myxoma to move away from the valve and relieves the symptoms.
Other symptoms of myxomas include
Raynaud syndrome Raynaud Syndrome Raynaud syndrome, a functional peripheral arterial disease, is a condition in which small arteries (arterioles), usually in the fingers or toes, narrow (constrict) more tightly than normal in... read more (the fingers and toes become cold and painful when exposed to cold)
Pieces of a myxoma or blood clots that form on the surface of the myxoma may break off (becoming emboli), travel through the bloodstream to other organs, and block arteries there. The resulting symptoms depend on which artery is blocked. For example, an artery in the brain blocked by tumor emboli from a left atrial myxoma may cause a stroke Overview of Stroke A stroke occurs when an artery to the brain becomes blocked or ruptures, resulting in death of an area of brain tissue due to loss of its blood supply (cerebral infarction) and symptoms that... read more , and an artery in the lung blocked by emboli from a right atrial myxoma may cause pain and coughing up of blood. Emboli are the most common complication of myxomas.
Other complications include certain blood abnormalities. A low red blood cell count (anemia Overview of Anemia Anemia is a condition in which the number of red blood cells is low. Red blood cells contain hemoglobin, a protein that enables them to carry oxygen from the lungs and deliver it to all parts... read more ) can cause fatigue, weakness, and paleness. A low platelet count, can cause problems with blood clotting How Blood Clots Hemostasis is the body's way of stopping injured blood vessels from bleeding. Hemostasis includes clotting of the blood. Too little clotting can cause excessive bleeding from minor injury Too... read more and people may have red spots (petechiae) or bruises on their skin.
Myxomas are suspected based on the person's symptoms. With a stethoscope, doctors may hear a sound (heart murmur The medical history and physical examination can suggest that a person has a heart or blood vessel disorder that requires additional testing for accurate diagnosis. When doctors "take a medical... read more ) produced by abnormal blood flow. The myxoma may block blood flow to or from the heart.
Because many symptoms of a myxoma may also be caused by many other disorders, extensive testing may be needed before a diagnosis is made.
Blood tests may show a high number of white blood cells (indicating inflammation), anemia, and a low number of platelets in the blood. But none of these tests is conclusive.
The diagnosis is confirmed by echocardiography Echocardiography and Other Ultrasound Procedures Ultrasonography uses high-frequency (ultrasound) waves bounced off internal structures to produce a moving image. It uses no x-rays. Ultrasonography of the heart (echocardiography) is one of... read more . Other imaging tests, including computed tomography Computed Tomography (CT) of the Heart Computed tomography (CT) may be used to detect structural abnormalities of the heart, the sac that envelops the heart (pericardium), major blood vessels, lungs, and supporting structures in... read more (CT) and magnetic resonance imaging Magnetic Resonance Imaging (MRI) of the Heart With magnetic resonance imaging (MRI), a powerful magnetic field and radio waves are used to produce detailed images of the heart and chest. This expensive and sophisticated procedure is used... read more (MRI), are sometimes necessary.