[Impending paradoxical embolism].

The case history of a 49-year-old female patient is reported, who was operated on because of varicose vein in the left lower extremity. A few days after the operation serious signs of cerebrovascular insult appeared. The clinical picture and the result of an urgent transoesophageal echocardiography are described; a serpentine thrombus was found to be trapped in the patent foramen ovale. During continuous intravenous heparin treatment, the patient gradually recovered, but a residual neurological deficit could be detected on discharge from the hospital. Six days after the admission, repeated transoesophageal echocardiographic examination showed no signs of intracardiac thrombus. The clinical feature of the illness, the predisposing factors, the diagnostic and therapeutic possibilities are discussed.