Wednesday, June 24, 2009

Cardiac Myxoma Histology

Electron microscopes are used in histology.


Histology is the part of biology that focuses on studying microscopic tissue structure. A scientist who studies such structures using an electron microscope is called a histologist. "Histogenesis," a subsection of histology, is a study of the origins of adverse conditions in tissue structure. Histology studies conditions that adversely affect tissue structure, including cancer. One type of cancer examined in histology is known as a "cardiac myxoma."


Definition


A cardiac myxoma is a cancerous neoplasm, or tumor, occurring in the heart muscle tissue, according to a Medscape article on cardiac neoplasms by Dr. Mary C. Mancini. It is also known as an "atrial myxoma." This condition is considered to be the most frequently occurring cardiac tumor, representing some 40 to 50 percent of all cardiac tumors. Cardiac myxoma can present histologists and physicians who treat the condition with diagnostic and treatment challenges.


A Challenging Diagnosis


According to the article by Dr. Mancini, a cardiac myxoma is often asymptomatic while growing within the heart muscle tissue. When symptoms exist, they are often mistaken for other heart conditions. Symptoms include rapid heartbeat, or tachycardia, fever and rapid breathing, or tachypnea. If the cardiac myxoma or cancerous tumor begins to increase in size, it can cause internal cardiac obstruction, resembling heart disease or congestive heart failure. Using histology to study changes in the microscopic tissue structure of the heart can help diagnose cardiac myxoma more accurately.


Histology Diagnosis


Histology can diagnose and also help locate cardiac myxomas because the tumors in heart tissue structure will appear "gelatinous" and differ from other cells when examined under an electron microscope. Histology is also used to tell the difference between two types of cardiac myxoma, according to an article in the journal "Cardiology Rounds" entitled: "Clinical and Genetic Aspects of Cardiac Myxomas" by Dr. Craig T. Basson of Brigham and Women's Hospital. Examination of tissue structure may also diagnose malignancy.


Histology Lab Test


Another laboratory test mentioned by Dr. Mancini in her article is the "Erythrocyte Sedimentation Rate" or ESR. Erythrocytes are the red blood cells that circulate in the blood stream. If lab test results show higher than normal levels of erythrocyte sedimentation, the detritus left from dead red blood cells, it may indicate that a cardiac myxoma is present.


Histogenesis


According to Histopathology-India.net, cardiac myxoma tissue structure is also studied by histologists to discover the type of already-existing cells from which it can develop. Histology studies have found that cells known as "mesenchymal," or embryonic cells present at birth, and "sub-endocardial" cells, which exist in the inner lining of the heart wall, can develop into cardiac myxomas.


Treatment


Surgical intervention, including resectioning to remove the cardiac myxoma, is the prescribed treatment, according to Medscape. When the cardiac myxoma is malignant, chemo and radiation therapy may also be prescribed. Some patients with co-existing conditions, such as high blood pressure, heart arrhythmia (irregular heartbeat) and paraganglioma-a tumor in the adrenal gland tissues-will require beta blocker therapy before surgery. While histology is not used in the surgical treatment of a cardiac myxoma, the heart's tissue structure must be monitored before and after treatment, particularly during chemo and radiation therapies.







Tags: tissue structure, cardiac myxoma, cardiac myxoma, according Medscape, blood cells, cardiac myxoma