Abstract 1122‐000127: An Alternative Reduced Dose Regimen of Ticagrelor for Patients Recieving Neuro‐Endovascular Procedures

Introduction : There is a growing use of Ticagrelor in patients undergoing neuroendovascular procedures, especially those who demonstrate Clopidogrel resistance. While multiple dosages are studied in the cardiology literature, the optimal dose for patients with neurological pathology has yet to be established. Here we describe a single center experience involving 39 patients who underwent neuroendovascular procedures that then received an adjusted lower dose of Ticagrelor. Methods : A retrospective chart review was performed between 2013 and 2017 for patients on dual antiplatelet therapy (DAPT) for either cervical or intracranial vascular pathologies, as well as stenting of the neurovasculature, including carotid arteries. Patients were placed on Ticagrelor if their measured PRU responses to Clopidogrel were outside the expected range in our center using the P2Y12 test. All patients were maintained on a dose of 45mg BID except for one patient who received 22.5 mg BID. Responsiveness to Ticagrelor were measured utilizing the P2Y12 test. Results : The mean number of days for follow up post treatment initiation was 532 days. A total of 39 patients were included in the analysis. Of these, 8 patients (21%) received implantation of intracranial stents (5 patients received pipeline embolization devices, 1 patient received stent‐ assisted coiling, and 2 patients received intra‐cranial stents for atherosclerotic disease). Fourteen patients (35%) received carotid angioplasty and stenting. Seventeen patients (44%) did not receive permanent implantation of a stent. All patients on the lower dose Ticagrelor of mg BID achieved responsiveness per the P2Y12 test. Hemorrhagic transformation of ischemic stroke occurred in one patient (2.5%). No other hemorrhagic complications were encountered. No thromboembolic events were recorded aside from one patient (2.5%) with intracranial atherosclerotic disease who had an ischemic event. Conclusions : A lower dose of Ticagrelor (45 mg BID) appears to be a safe and effective in this small cohort of patients who are resistant to Clopidogrel per P2Y12 testing and who have increased risk of ischemic or hemorrhagic strokes due to neurovascular pathologies and implants. Further randomized studies are required to confirm these findings.

Transcarotid artery revascularization (TCAR): a technical video

Carotid revascularization is an important method of stroke prevention and includes carotid endarterectomy and transfemoral carotid angioplasty and stenting. More recently, a hybrid open-endovascular approach, termed transcarotid artery revascularization (TCAR), is garnering increased attention. Although fundamentally a ‘stenting procedure’, unlike transfemoral carotid angioplasty and stenting, TCAR allows for a proximal neuroprotection strategy based on flow reversal. In this technical video, we will review operative techniques and nuances of the TCAR procedure, with a particular focus on the neurovascular proceduralist looking to adopt this technique into routine clinical practice(video 1).Video 1

Results of carotid stenting for asymptomatic carotid artery stenosis

Objective: prospective analysis of 30-day outcomes from stenting procedure in patients with asymptomatic internal carotid artery stenosis depending on the type of implanted stent. Material and Methods: the study included 108 patients who underwent endovascular surgical treatment for asymptomatic internal carotid artery stenosis from 2012 to 2017. Depending on the type of implanted stent the patients were divided into 4 groups (the first (n = 37) – steel, the second (n = 32) -nitilon, the third (n = 20) – doublelayered stents, the fourth (n = 19) – double-layer stents with an inner layer of polyethylene terephthalate. Results: there was no mortality in the studied groups for 30 days after surgery. The cumulative incidence of cerebral circulation disorders within 30 days of carotid angioplasty and stenting was 9.7% (n = 10), with ischemic stroke occurring in 1.85% (n = 2) cases. Conclusion: carotid angioplasty and stenting is a safe and effective method of secondary prevention of cerebral circulation disorders with the level of perioperative complications not exceeding other preventive procedures.

Functional MRI evaluation of the effect of carotid artery stenting: a case study demonstrating cognitive improvement

Background The narrowing of the carotid arteries with plaque formation represents a major risk factor for ischemic stroke and cognitive impairments. Carotid angioplasty and stenting is a standard clinical treatment to reduce stroke risk. The cognitive effect of carotid angioplasty and stenting remains largely unknown. Purpose This study aims to provide direct evidence of possible effects of carotid angioplasty and stenting on cognition, using task-phase functional magnetic resonance imaging. Material and Methods This study received harmonized institutional ethics board approval (Grant number REB ID =H18-02495/FHREB 2018-058). Two patients had MRI scans pre-carotid angioplasty and stenting and two-month post-carotid angioplasty and stenting. Case 1 had severe (>95%) flow-limiting stenosis in the right carotid artery. Case 2 had 70% non-flow limiting stenosis in the left carotid artery. At each scan, patients completed two functional magnetic resonance imaging sessions while performing a working memory task. Accuracy, reaction time, and brain activation were analyzed for each patient for possible pre-post carotid angioplasty and stenting changes. Results Case 1 showed increased activation in the right (treated-side) frontal and temporal lobes post-carotid angioplasty and stenting; associated with improvements in accuracy (from 58% to 74%) and task completion rate (from 17% to 72%). Case 2 completed the tasks pre- and post-carotid angioplasty and stenting with >90% accuracy, while decreased functional magnetic resonance imaging activation in the contralateral (untreated) hemisphere and mildly increased activation in the left (treated -side) anterior circulation territory were observed post-carotid angioplasty and stenting. Conclusion These cases provided the first task-phase functional magnetic resonance imaging data demonstrating that carotid angioplasty and stenting improved cognitive function in the re-perfused vascular territory. The finding supports the role of carotid angioplasty and stenting in improving cognitive performance beyond reducing stroke risk.

Vascular

This chapter explores vascular diseases. The first set of studies discusses the natural history of unruptured intracranial aneurysms, examines the clinical outcomes of surgical and endovascular treatment, and assesses the safety and efficacy of endovascular coiling and neurosurgical clipping of ruptured intracranial aneurysms. The second set of studies compares carotid endarterectomy versus carotid angioplasty and stenting for the treatment of carotid artery stenosis, determines the efficacy of endovascular therapy after intravenous tissue plasminogen activator (tPA) versus tPA alone for the treatment of acute ischemic stroke, and tests the efficacy of endovascular thrombectomy. The third set of studies identifies risk factors for hemorrhage in patients with untreated brain arteriovenous malformation (BAVM) and looks at the management of unruptured BAVM. The fourth set of studies evaluates the effect of early neurosurgical intervention in patients with superficial lobar intracerebral hemorrhage and tests the hypothesis that minimally invasive hematoma evacuation along with the use of recombinant tissue-type plasminogen activator (rtPA) could safely reduce hematoma size and perihematomal edema. Finally, the last study describes the management of giant intracranial aneurysms.

Relationship between ophthalmic artery flow direction and visual deterioration after carotid angioplasty and stenting

OBJECTIVEVisual deterioration is one of the disabling complications that can occur after carotid angioplasty and stenting (CAS). The purpose of this study was to evaluate the risk factors for newly developed visual symptoms after CAS, focusing on ophthalmic artery (OA) flow pattern and etiology of visual loss.METHODSA retrospective review of 127 patients with 138 internal carotid artery (ICA) stenosis lesions that were treated with CAS from February 2009 to October 2017 in a single institution was performed. The flow pattern of the OA was evaluated with digital subtraction angiography and classified into 3 types: type I, antegrade OA flow before and after CAS; type II, antegrade OA flow reversal after CAS; and type III, retained nonantegrade OA flow after CAS.RESULTSThe degree of ipsilateral ICA stenosis was significantly higher in the nonantegrade group than that in the antegrade group (81.73% ± 9.87% vs 75.74% ± 10.27%, p = 0.001). Independent risk factors for newly developed visual symptoms after CAS were visual symptoms before CAS (OR 65.29, 95% CI 5.14–827.2; p = 0.001) and type III OA flow pattern (OR 55.98, 95% CI 2.88–1088.0; p = 0.008). The post-CAS visual symptoms in 10 patients were related to acute elevation of intraocular pressure in 6 patients and retinal artery occlusion in 3 patients.CONCLUSIONSMaintained retrograde or undetected OA flow after CAS and initial visual symptoms before CAS were related to post-CAS visual symptoms. Thus, careful attention is needed for these patients during the perioperative period, and immediate evaluation and management are required for patients with post-CAS visual loss.