Case of paradoxical embolic transient ischemic attack from an unusual extra cardiac shunt detected on a contrast-enhanced echocardiogram.

Paradoxical embolism due to extracardiac right to left shunts (RLSs) manifesting as stroke remains anecdotal. We describe a case of 63-year-old female who presented with a transient ischemic attack and at agitated saline contrast echocardiogram was found to have an unusual type of an extracardiac RLS. Further evaluation leads to diagnosis of superior vena cava (SVC) thrombosis from a prior indwelling central venous catheter. The SVC thrombosis induced systemic-pulmonary venous collaterals were responsible for this unusual extracardiac RLS and paradoxical transient ischemic attack. We discuss the diagnosis and management of this rare clinical case.