Mechanical Thrombectomy Using the Solitaire FR system for Occlusion of the Top of the Basilar Artery: Intentional Detachment of the Device after Partial Retrieval
A 67-year-old male presented in our emergency department complaining sudden, severe dizziness and left ptosis of an hour's duration. On admission, his symptoms gradually worsened, showing left-side facial palsy, severe dysarthria, and left-limb ataxia. He was on oral anticoagulation with a daily aspirin since he had a mechanical aortic valve replaced more than a year previously. However, his international normalization ratio (INR) on admission turned out to be only 1.4.\nSubsequent, acute stroke MR imaging showed occlusion of the basilar artery with a focal infarction in the left superior cerebellar artery territory (). Systemic tissue plasminogen activator (Actylase, Boehringer Ingelheim, Germany) was given at a dose of 0.6 mg/kg as the patient was still within the time window of intravenous thrombolytic therapy. Because the patient did not show any symptomatic improvement, our endovascular treatment team was called in per our institutional acute stroke bridging therapy protocol.\nRight vertebral angiogram showed a typical pattern of BAO. The lesion showed antegrade flow directly after placement of the SFR (). However, the f irst retrieval was unsuccessful and only showed a slight change in the shape of the filling defect. The pattern repeated during several, following trials. Eventually, the clot migrated further distally into the left posterior cerebral artery ().\nAt the time of the final device retrieval, we obtained a control angiogram while the device was still in the midportion of the basilar trunk (). We were able to retract the filling defect proximally into the mid portion of the basilar trunk. However, it was attached at the distal tip of the device. Eventually we could pull down the device to the distal vertebral artery (VA) level proximal to the ipsilateral posterior inferior cerebellar artery (PICA) origin.\nOn the control angiogram we noted that half of the filling defect had migrated into the right PCA and half of it was still within the device mesh as we thought that further manipulation of the device would result in additional distal migration of the clot, we decided to purposely detach the device at the current position in order to avoid the risk of another distal migration ().\nA loading dose of tirofiban (Aggrastat, Iroko Cardio Australia Pty Ltd, Australia) was given systemically on the table. On the following day, the patient's symptoms improved significantly and only showed mild residual diplopia on the left lateral gaze. A dual antiplatelet regimen was initiated on top of oral anticoagulation.\nFollow-up MR showed no new infarcts even in the right PCA territory. There was also no evidence of any hemorrhagic transformation. The patient was discharged with instructions to take both aspirin and warfarin after adjustment of the INR.