Paradoxical brain embolism with Klippel-Trenaunay syndrome

Cerebrovascular diseases in patients with Klippel-Trenaunay Syndrome (KTS) are uncommon, and the mechanism of stroke has remained elusive. We describe a patient with KTS who experienced a transient ischemic attack (TIA). Contrast-transcranial Doppler with the Valsalva maneuver revealed a right-to-left shunt and contrast-transesophageal echocardiography confirmed patent foramen ovale. Ultrasonography revealed dilated superficial and deep veins in the lower extremities; the D-dimer level was high and indicated hypercoagulability. Therefore, the mechanism of TIA was diagnosed as paradoxical embolism. To the best of our knowledge, this is the first case report of paradoxical embolism in a patient with KTS.