Pericardial Mesothelioma (definition of)

Pericardial mesothelioma is the rarest form of the three major types of malignant mesothelioma. Mesothelioma itself affects the mesothelium, the thin layer of cells that lubricate the lungs, the heart, and the stomach and intestines. Pericardial mesothelioma attacks mesothelium surrounding the heart, which is known as the pericardium.

The pericardium supports and protects the heart muscle, providing lubrication for the heart's beating motion. It consists of two layers: the visceral layer, which is next to the heart itself, and the external parietal layer. Pericardial fluid forms between these two layers.

It is not fully understood by medical science how asbestos fibers enter the heart itself. It is likely however that these microscopic fibers enter the bloodstream and travel throughout the body via the circulatory system, eventually entering the heart chamber itself, where they bare through the muscle from the inside out, causing chronic inflammation that ultimately causes the cellular mutation that leads to mesothelioma.

Little is known about pericardial mesothelioma, since it affects so few patients; most cases are of the pleural (lung) variety; peritoneal mesothelioma (abdomen) is the second most common. Pericardial mesothelioma symptoms include breathing difficulties resulting from pressure on the heart muscle from the buildup of tumor mass. The fluid buildup in the pericardium causes blood to flow with greater difficulty, and the ventricles cannot reach their full capacity. Known as cardiac tamponade, this can manifest itself as elevated heart rate or an abnormal pulse as the heart muscle must strain in order to provide the body with sufficient blood flow. Because this can cause pain in the heart area, many sufferers of pericardial mesothelioma mistake their symptoms for an impending heart attack.

Prognosis for patients diagnosed with pericardial mesothelioma is poor; most die within a year of their diagnosis. There are no effective treatments for malignant mesothelioma other than palliative ones, and because the pericardial variety involves the heart itself, it is particularly difficult to deal with.