[Transient paradoxical embolism. Importance of early ultrasonography diagnosis]. / Embolia paradójica en tránsito. Importancia del diagnóstico ecocardiográfico precoz.

The paradoxical embolism or the crossing of an embolism through a permeable foramen ovale is considered to be a rare mechanism of cerebral embolism although its real frequency is unknown. Reports demonstrating the embolism during its crossing through cardiac cavities are scarce. Two cases of moving paradoxical embolism are presented. In the first, an infarction of the superior branch of the left middle cerebral artery was produced during the course of deep vein thrombosis and pulmonary thromboembolism with transesophageal echocardiography demonstrating the crossing of the embolism through the foramen ovale. Surgery performed 12 days later did not discover the auricular thrombus. In the second case, a mass was discovered in the right auricle with a permeable foramen ovale during the course of a left middle cerebral artery infarction and a large auricular thrombus was demonstrated in surgery. The diagnostic usefulness of early transsesophageal echocardiography in the diagnosis of moving paradoxal embolism is discussed.