Thrombotic "ghosts": echocardiographic appearance of thrombi with hollow cores and implications regarding mechanism of spontaneous clot lysis.

We present a case of a patient whose transesophageal echocardiogram revealed multiple thrombi in different stages of central lysis. This produced the appearance of undulating thin outer shells and lucent central cores resembling "ghosts." Although most thrombi appear to resolve by a lytic process that produces reduction in size from the exterior surface inward, the thrombi illustrated in this case appear to lyse from the interior outward. In this report we discuss the mechanisms of intracardiac clot lysis and speculate that a newly described protein factor, thrombin-mediated inhibition of fibrinolysis, may play a role in formation of hollow thrombi.