[A case of paradoxical cerebral embolism through a patent foramen ovale diagnosed by necropsy].

A 62-year-old man was admitted to our hospital for disturbed consciousness and left-side motor sensory deficit. His blood pressure was 142/100 mmHg and an electrocardiogram was normal. CT of the brain revealed a low density area in the distribution of the right middle cerebral artery (MCA). Cerebral angiography demonstrated occlusion of the right internal carotid artery and an embolus. We diagnosed cerebral embolism, but we could not detect source of embolism. His condition deteriorated rapidly, and he died four days later. At necropsy, an elongated piece of thrombus 10 cm in length was lodged in a patent foramen ovale lying in each atrium. No other thrombus was seen in the heart, the myocardium and coronary arteries were normal. Both main pulmonary arteries contained thrombus. The lungs showed edema and congestion. There was no thrombus of both common iliac veins. The right internal carotid artery was occluded at its bifurcation by embolus, distal to which the cavernous segment was 7 cm filled with clot. We reported a rare paradoxical cerebral embolism through a patent foramen ovale diagnosed by necropsy. If no left-sided circulatory source can be demonstrated, the possibility of a paradoxical embolism should be considered.