Tumors that originate in the heart are rare, but can be either benign or malignant.
Because the heart is such an essential organ, even benign tumors can be life-threatening. Benign tumors include:
- Myxoma, is the most common tumor inside the cavities of the heart and accounts for about half of the tumors that originate in the heart. Most of these tumors occur in the left atrium of the heart
- Rhabdomyomas, which develop in the myocardium or the endocardium and account for about one out of every five tumors that originate in the heart. Most of these occur in children or infants and are associated with tuberous sclerosis, adenoma sebaceum of the skin, kidney tumors and arrhythmias. These tumors tend to occur in multiples inside the wall of the ventricle.
- Fibromas, which also develop in the myocardium or the endocardium. These tumors tend to occur on the valves of the heart and may be related to inflammation
- Teratomas of the pericardium, often attached to the base of the great vessels, usually occur in infants. They are rarer than cysts or lipomas, usually cause no symptoms. They are often discovered on routine chest x-ray. Surgery done only to rule out more serious tumors
- Pericardial cysts, and
Malignant heart tumors can originate from any heart tissue. They occur mostly in children. These types of tumors include:
- Angiosarcomas, which account for about a third of all malignant heart tumors. They start usually on the right side of the heart.
Malignant tumors that originated elsewhere in the body and spread to the heart are more common than ones that originate in the heart. Malignant tumors, including carcinomas, sarcomas, leukemias and reticuloendotheliar tumors, can spread to any heart tissue. Lung and breast cancers often invade the heart. Malignant melanomas have one of the highest rates of spreading to the heart.
Because tumors in the heart can mimic other heart diseases, they are difficult to diagnose accurately. Tumors of the heart may involve the:
- Epicardium, the sheath of tissue that covers the heart
- Myocardium, the muscles of the heart wall
- Endocardium, the membrane that lines the cavities of the heart
The symptoms and signs of the condition tend to indicate what part of the heart is affected. If a person who has malignant tumors in another part of their body develops symptoms of heart disease, it may be a sign that the tumor has spread to the heart.
Myxoma cause three general patterns of symptoms:
- Symptoms that mimic such conditions as bacterial endocarditis, collagen-vascular disease and clinically undetectable malignancies
- Embolisms, in which fragments of the tumor breakaway into the blood stream and causes clots or blockages
- Blockages of the blood flow. Blood flow may be blocked at the opening of any heart valve, commonly the mitral valve.
Interference in the way the heart works by the tumor can create symptoms similar to valve disorders caused by rheumatic disease including lung congestion and heart murmurs. The precise sounds may be different in myxoma compared to actual mitral valve disorders especially when the position of the body is changed. Usually people with myxoma don¿t have the amount of enlargement of the left atrium as persons who have valve disease do.
Cardiac symptoms of rhabomyomas and fibromas include:
- Rapid heart beats
- Enlargement of the heart
- Signs of a blockage to the flow of blood out of the ventricles
- Heart murmurs
If cardiac symptoms are also present with features of tuberous sclerosis, there is probably a benign tumor present. This can be confirmed by echocardiography or angiocardiography. Surgical treatment of multiple nodules is usually ineffective, and the prognosis is poor beyond the first year of life.
Symptoms of a heart tumor caused by the spread of a malignancy from another part of the body include:
- Sudden enlargement of the heart,
- Bizarre changes in the shape of the heart on a chest x-ray
- A blockage
- Irregular heart rhythms
- Unexplained heart failure
Symptoms of malignant cardiac tumors that originate in the heart may include:
- Sudden heart failure
- A rapid accumulation of bloody fluid in the lining around the heart, often with a blockage of the blood flow in the heart
- Various kinds of arrhythmias
Compared to benign tumors, malignant cardiac tumors tend to cause more severe and rapid deterioration and may spread to the spine, nearby soft tissues and major organs.
Causes and Risk Factors
Myxomas tend to run in families and may be at least partially genetic. Having a malignant tumor in another part of the body that can spread to heart - especially, melanoma, breast or lung cancer - can put you at a greater risk of developing a malignant tumor of the heart.
Myxoma can be diagnosed as follows:
- From the symptoms the patient has
- An echocardiogram
- Occasionally, cardiac catheterization
- Occasionally, a biopsy of the endocardium or the myocardium
- Gated pool scintigraphy
- Computer tomography
- Magnetic resonance imaging
- Angiocardiography is also used, although infrequently.
Rhabomyomas and fibromas can be diagnosed on the basis of the symptoms they produce. If cardiac symptoms are also present with features of tuberous sclerosis, there is probably a benign tumor present. This can be confirmed by echocardiography or angiocardiography.
Atrial tumors, especially right atrial myxomas, may contain calcium deposits visible in a chest X-ray.
Untreated benign cardiac tumors may be life threatening. Treatment of myxoma is usually done by surgical removal of the tumor.
Surgery to remove multiple nodules when Rhabomyomas and fibromas are present is usually not effective. Most infants and children with these tumors don't survive beyond the first year of life.
Teratomas, which usually occur in infants, are also usually surgically removed even though they don¿t cause symptoms. In this case, the surgery rules out the growth of more serious tumors.
Treatment of malignant cardiac tumors usually involves radiation, chemotherapy and management of complications. The expected outcomes for these types of tumors is poor.