Long term stent patency and revascularization rates after emergent carotid stenting during stroke thrombectomy

Emergent carotid artery stenting (eCAS) performed during endovascular treatment (EVT) for acute ischemic stroke (AIS) is associated with increased rates of stent thrombosis. Very limited data is available regarding long-term carotid stent patency or target lesion revascularization (TLR) rates beyond the first 24 hours post EVT. We retrospectively analyzed a prospectively maintained stroke EVT database at Strasbourg University Hospitals, including all consecutive patients treated with eCAS during EVT for AIS with tandem lesions (TL) or isolated carotid artery occlusion (ICAO), between November 2009-September 2024. A total of 220 patients were included in the study, of which 207 TL and 13 ICAO. Stent occlusion or severe stenosis at 24 hours was observed in 8.6% of cases. Follow-up imaging beyond day 1 (median 112 days, IQR 30-216) revealed two additional cases of stent occlusion (1.3%) at day 4 and 5. In-stent restenosis (at least 50%) was observed in 4.3% of cases after a median interval of 13 months; all these patients had underlying carotid atheroma. TLR was performed in 3% of cases. The cumulative incidences of restenosis at 1 and 2 years were 9.8% (95%CI 0.8-18.8) and 22% (95%CI 3.3-40.7%) respectively. Stent occlusion was predominantly observed within the first 24 hours, with only rare occurrences thereafter. The incidence of long-term in-stent restenosis aligns with previously reported rates for elective CAS, performed outside the context of acute stroke EVT. Further prospective research is required to reduce the rates of stent occlusion within the first 24 hours. eCAS = emergent carotid artery stenting; EVT = endovascular treatment; TLR = target lesion revascularization; TL = tandem lesions; ICAO = isolated carotid artery occlusion; IQR = interquartile range; CAS = carotid artery stenting; LVO = large vessel occlusion; AIS = acute ischemic stroke; sICH = symptomatic intracranial hemorrhage; DAPT = dual antiplatelet treatment; mTICI = modified Thrombolysis in Cerebral Infarction scale; HI1, HI2 = hemorrhagic infarction type 1, type 2; PH1, PH2 = parenchymal hematoma type 1, type 2.