Bihemispheric Paradoxical Cerebral Embolism in a Patient with Pulmonary Thromboembolism and Presumptive Fistula Right-to-Left Shunt.

We report a case of a bihemispheric paradoxical cerebral embolism in a patient with pulmonary thromboembolism and presumptive pulmonary arteriovenous fistula. The echocardiogram showed no intracardiac shunt, and the transcranial Doppler (TCD) revealed spontaneous microembolic signals in the middle cerebral arteries (MCAs), and late passage of a higher number of microembolic signals in the MCAs, compatible with right-to-left shunt (RLS). The TCD and the echocardiogram were useful for identifying the RLS when rapid neurological deterioration occurred.