These lyse within hours to days, but a partially lysed embolus may resemble an irregularly inflamed vessel. Emboli from atrial myxoma, however, can invade the endothelial wall and produce a true inflammatory vasculitis both in clinical presentation and neuroimaging appearance. This was first described in the late 1950's. The incidence seems to be increasing although these numbers may be biased by the better dectection techniques and increasing suspicion among physicians. The average age of onset is about 45 years with an equal distribution between the sexes.
Constitutional symptoms are generally absent.
Physcial exam may reveal focal neurologic defects or an encephalopathy. There are no consistent abnormalities in serologies or autoimmune markers. Analysis of the cerebrospinal fluid may be normal. Most commonly, there is an elevation of protein often accompanied by a small pleocytosis. Both neutrophilic and lymphocytic pleocytosis has been reported.