Use of the Parodi Anti-Emboli System and transient subclavian steal for cerebral protection during emergent vertebral artery recanalization.

PURPOSE: To report the use of the Parodi Anti-Emboli System (PAES) for cerebral protection during emergent vertebral artery recanalization. CASE REPORT: A 56-year-old chimney sweep was referred with recurrent episodes of vertigo and gait ataxia. Left vertebral artery (LVA) flow was barely detectable on duplex Doppler, and brain computed tomography revealed a small infarct in the posterior inferior cerebellar artery territory. Angiography showed subtotal ostial stenosis of the LVA with poor distal flow and possible thrombus. Due to a high risk of distal embolization with percutaneous treatment, anticoagulation was initiated, and the lesion was to be re-evaluated in 2 to 3 weeks. However, 2 days later, the patient developed severe, aggravating headache, gait and left-limb ataxia, horizontal nystagmus, and vomiting. Emergent angiography showed a total ostial LVA occlusion. The PAES was employed to elicit a temporary subclavian steal during percutaneous LVA recanalization, thus protecting the brain from embolization. The ostial LVA was successfully recanalized and stented, with immediate symptom cessation. CONCLUSIONS: The PAES can be successfully applied in the subclavian artery to prevent distal embolization during emergent vertebral artery recanalization. Since a significant proportion of vertebral strokes are embolic, PAES may play a novel role in the treatment of acute cerebellar stroke.