E-185 Medical management of in-stent stenosis following pipeline embolization of brain aneurysms

Introduction Flow diversion of intracranial aneurysms with the Pipeline embolization device (PED) may produce angiographically apparent stenosis within the PED, which can lead to secondary ischemic complications. In-stent stenosis can be treated medically with dual antiplatelet therapy (DAPT), but the safety and efficacy of this approach is unknown. In this work, we review the safety and efficacy of DAPT to prevent progression of in-stent stenosis or development of cerebral ischemia. Methods Clinical and angiographic data from eligible patients were assessed from a prospectively maintained neurointerventional database. Details surrounding in-stent stenosis and DAPT were extracted. Patients were included in this study if in-stent stenosis was detected at any angiographic follow-up and managed with DAPT. The primary efficacy endpoint was lack of angiographic progression of in-stent stenosis or new ipsilateral infarct following initiation of medical therapy. Results In total, 23 PED constructs developed in-stent stenosis and were managed with DAPT. Follow-up angiography was available for 19 constructs. 89% (17/19) of PED constructs achieved the primary endpoint of lack of stenosis progression and new ipsilateral ischemic events. Of the two PED constructs that failed to achieve the primary endpoint of this study, one demonstrated worsening of in-stent stenosis from 55% to 76% over 16 months, while the other developed ipsilateral ischemic stroke 4 months after detection of in-stent stenosis. In addition, one patient experienced intracranial hemorrhage 9 months after the initiation of DAPT. Conclusions Progression of in-stent stenosis and new ipsilateral ischemic events are limited in the presence of DAPT. However, hemorrhagic events related to DAPT may occasionally occur. Disclosures D. Lauzier: None. S. Cler: None. J. Osbun: 2; C; Medtronic, Microvention. A. Chatterjee: None. C. Moran: 2; C; Medtronic, Cerenovus. A. Kansagra: 2; C; Microvention, Penumbra.