Abdulnasser Alhajeri

Systematic Evaluation of Patients Treated With Neurothrombectomy Devices for Acute Ischemic Stroke: Primary Results of the STRATIS Registry

Background and Purpose— Mechanical thrombectomy with stent retrievers has become standard of care for treatment of acute ischemic stroke patients because of large vessel occlusion. The STRATIS registry (Systematic Evaluation of Patients Treated With Neurothrombectomy Devices for Acute Ischemic Stroke) aimed to assess whether similar process timelines, technical, and functional outcomes could be achieved in a large real world cohort as in the randomized trials. Methods— STRATIS was designed to prospectively enroll patients treated in the United States with a Solitaire Revascularization Device and Mindframe Capture Low Profile Revascularization Device within 8 hours from symptom onset. The STRATIS cohort was compared with the interventional cohort of a previously published SEER patient-level meta-analysis. Results— A total of 984 patients treated at 55 sites were analyzed. The mean National Institutes of Health Stroke Scale score was 17.3. Intravenous tissue-type plasminogen activator was administered in 64.0%. The median time from onset to arrival in the enrolling hospital, door to puncture, and puncture to reperfusion were 138, 72, and 36 minutes, respectively. The Core lab–adjudicated modified Thrombolysis in Cerebral Infarction ≥2b was achieved in 87.9% of patients. At 90 days, 56.5% achieved a modified Rankin Scale score of 0 to 2, all-cause mortality was 14.4%, and 1.4% suffered a symptomatic intracranial hemorrhage. The median time from emergency medical services scene arrival to puncture was 152 minutes, and each hour delay in this interval was associated with a 5.5% absolute decline in the likelihood of achieving modified Rankin Scale score 0 to 2. Conclusions— This largest-to-date Solitaire registry documents that the results of the randomized trials can be reproduced in the community. The decrease of clinical benefit over time warrants optimization of the system of care. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT02239640.

Intra-arterial verapamil post-thrombectomy is feasible, safe, and neuroprotective in stroke:

Large vessel ischemic stroke represents the most disabling subtype. While t-PA and endovascular thrombectomy can recanalize the occluded vessel, good clinical outcomes are not uniformly achieved. We propose that supplementing endovascular thrombectomy with superselective intra-arterial (IA) verapamil immediately following recanalization could be safe and effective. Verapamil, a calcium channel blocker, has been shown to be an effective IA adjunct in a pre-clinical mouse focal ischemia model. To demonstrate translational efficacy, mechanism, feasibility, and safety, we conducted a group of translational experiments. We performed in vivo IA dose–response evaluation in our animal stroke model with C57/Bl6 mice. We evaluated neuroprotective mechanism through in vitro primary cortical neuron (PCN) cultures. Finally, we performed a Phase I trial, SAVER-I, to evaluate feasibility and safety of administration in the human condition. IA verapamil has a likely plateau or inverted-U dose–response with a defined toxicity level in mice (LD50 16–17.5 mg/kg). Verapamil significantly prevented PCN death and deleterious ischemic effects. Finally, the SAVER-I clinical trial showed no evidence that IA verapamil increased the risk of intracranial hemorrhage or other adverse effect/procedural complication in human subjects. We conclude that superselective IA verapamil administration immediately following thrombectomy is safe and feasible, and has direct, dose–response-related benefits in ischemia.

The Blood And Clot Thrombectomy Registry And Collaboration (BACTRAC) protocol: novel method for evaluating human stroke

Background Ischemic stroke research faces difficulties in translating pathology between animal models and human patients to develop treatments. Mechanical thrombectomy, for the first time, offers a momentary window into the changes occurring in ischemia. We developed a tissue banking protocol to capture intracranial thrombi and the blood immediately proximal and distal to it. Objective To develop and share a reproducible protocol to bank these specimens for future analysis. Methods We established a protocol approved by the institutional review board for tissue processing during thrombectomy (www.clinicaltrials.gov NCT03153683). The protocol was a joint clinical/basic science effort among multiple laboratories and the NeuroInterventional Radiology service line. We constructed a workspace in the angiography suite, and developed a step-by-step process for specimen retrieval and processing. Results Our protocol successfully yielded samples for analysis in all but one case. In our preliminary dataset, the process produced adequate amounts of tissue from distal blood, proximal blood, and thrombi for gene expression and proteomics analyses. We describe the tissue banking protocol, and highlight training protocols and mechanics of on-call research staffing. In addition, preliminary integrity analyses demonstrated high-quality yields for RNA and protein. Conclusions We have developed a novel tissue banking protocol using mechanical thrombectomy to capture thrombus along with arterial blood proximal and distal to it. The protocol provides high-quality specimens, facilitating analysis of the initial molecular response to ischemic stroke in the human condition for the first time. This approach will permit reverse translation to animal models for treatment development.

P-010 Practice variations in addressing acute tandem carotid occlusions in emergent large vessel occlusion strokes

Introduction/Purpose There are, at present, no standardized clinical practice guidelines addressing the endovascular management of acute ischemic stroke attributable to tandem occlusive disease (cervical carotid occlusion with intracranial large vessel occlusion). We conducted a systematic review of available literature, as well as reviewed cases from our own institution, in order to identify current practice variants, and highlight neurointerventional approaches that are most frequently utilized. Materials and Methods We conducted a retrospective review of patients with acute ischemic stroke secondary to a tandem occlusion (intracranial occlusion with concomitant extracranial steno-occlusive carotid disease) that were treated with emergent thrombectomy from July 1, 2011 to December 31, 2015 at the University of Kentucky. Clinical (age, gender, stroke risk factors, NIHSS at admission), radiographic (distribution of intracranial occlusion), and interventional (recanalization technique for extra- and intracranial steno-occlusive disease, peri- and post-operative anti-coagulation/anti-platelet, and time to recanalization) data were collected. Using the PubMed database, we conducted a review of available literature from ?January 1, 2011 through February 28, 2017 on the endovascular treatment of tandem occlusions, extracting the same clinical, radiographic, and interventional data when available. Results 29 studies (Mean age: 65.2; Mean NIHSS on admission: 15.7) were included. 28 (97%) carried out acute stent-assisted recanalization of the cervical ICA, with 25 (89%) using adjunctive angioplasty. 18 (64%) of these favored the proximal-to-distal approach. 13 (45%) utilized systemic heparinization. 7 (24%) utilized general anesthesia for all cases, 6 for majority (21%), and 3 (10%) for some (no distribution given). Loading doses (LD) of aspirin and clopidogrel were given before stenting in 7 (24%) and post-procedure in 2 (7%). Aspirin alone before stenting was used in 3 (10%) and after in 6 (21%), with 5 of these 9 giving clopidogrel LD post-procedure. 5 (17%) reported peri-procedural GPIIb/IIIa inhibitors. 19 (68%) addressed maintenance antiplatelet regimens, all using aspirin and clopidogrel. For our institution, 10 patients (Mean age: 60, Mean NIHSS at admission: 16.3) were included. 4 underwent acute stenting (50% proximal-to-distal approach); 2 underwent angioplasty alone, 2 underwent thromboaspiration alone, and 2 underwent IA tPA alone. 1 case used systemic heparinization. General anesthesia was used in 5 patients. 2 received aspirin LD and 1 aspirin and clopidogrel LD post-procedure. 3 discharged on aspirin and clopidogrel, 2 on aspirin alone. Conclusion For tandem occlusions with cervical ICA involvement, acute stenting with adjunctive angioplasty, is a current prevailing practice for recanalization of the extracranial ICA. There is considerable variability in antiplatelet protocols, with a slight favoring of the administration of loading doses of aspirin and clopidogrel before stent deployment. Variability is also present for anesthesia, with general anesthesia having a significant role. Disclosures S. Coffman: None. S. Trott: None. A. Alhajeri: None. J. Fraser: None.

E-067 Institutional trends in mechanical thrombectomy: lessons learned

Introduction Ischemic stroke is a devastating condition resulting in significant morbidity and mortality. Strong positive results of randomized trials have established mechanical thrombectomy as a mainstay for large vessel occlusive stroke, with significant improvements in functional outcomes. Our aim was to examine our thrombectomy procedures, and to evaluate relationships in practice change and development that could inform the adoption and selection of techniques. Methods Retrospective review was conducted on mechanical thrombectomy cases from July, 2011 through December, 2015. Patients must have been 18 years old, diagnosed with ischemic stroke, and were treated with thrombectomy. Primary outcomes were time to recanalization, final TICI score, procedural complications, NIHSS improvement, mortality, and incidence of single pass thrombectomy. Results 130 procedures were performed. 79.1% had a TICI score of at least 2b. Achieving a TICI score of 3 significantly improved over time (OR = 1.5, p = 0.004). 30% of thrombectomies were single pass. When evaluated by technique, single pass recanalization was achieved with reperfusion catheter alone in 52%, with stent-triever alone in 27%, and with combination techniques in 26% (Chi-squared 6.04, p = 0.048). In regards to technique used, 42.3% were a combination of reperfusion catheter and stent-triever, 19.2% were reperfusion catheter alone, and 31.5% were stent-triever alone. Procedural mortality was 0.77% (one patient). Improvement in NIHSS following thrombectomy became significantly better each year with the difference between NIHSS on discharge vs. on arrival dropping by -1.88 each year (p = 0.00416). Additionally, improvement in NIHSS had a significant inverse association with time to recanalization (p = 0.000398) Conclusions: Preliminary data suggest that thrombectomy is a safe procedure that results in extremely low mortality and significant decreases NIH score over time, which may point to better functional outcome. Overall, there was an improvement in NIHSS reduction with time. Additionally, achieving faster times to recanalization resulted in better improvements in NIHSS. There was a significant difference in the ability of different techniques to achieve first-pass recanalization, though this may reflect clinical judgments about when to use each technique. Producing a TICI score of 3 also improved over time, demonstrating increased ability to recanalize at our institution over time. Disclosures: S. Trott: None. O. Vsevolozhskaya: None. A. Alhajeri: None. J. Fraser: None.

P-024 Scepter C™ Balloon Occlusion Device use for Liquid Embolisation of Vascular Malformations, a Pilot Study

Objective The Scepter C™ balloon occlusion catheter (Microvention, Tustin CA) is an endovascular device designed with a polyurethane balloon that elongates with inflation to allow it to conform to the lumen of the target vessel. The device has a double lumen, allowing passage over a 0.014-inch guidewire, and/or passage of Onyx embolisation distal to the balloon. We reviewed our initial use of this device as a conduit for liquid embolisation of vascular malformations as compared to the Marathon™ microcatheter (ev3, Plymouth, MN) alone, outlining indications for and outcomes with use. Methods We performed a retrospective review of patients who underwent Onyx embolisation of an arterovenous malformation or a dural A-V fistula from October 2011 to February 2013 at the University of Kentucky Hospital. Results 14 Scepter C™ devices were used in 8 patients over the course of 10 endovascular interventions. We compared this to 8 patients treated with 11 embolisations over the course of 9 interventions without balloon assistance. Technical success was achieved in 13/14 (93%) deployments of the balloon. There were no complications related to Scepter C™ use. Scepter C™ permitted distal navigation, while facilitating faster Onyx injection with more extensive and distal casting. This led to a trend of decreased fluoro time per embolisation with Scepter C™, though not statistically significant (23.0 ± 8.8 min vs 34.0 ± 10.4 min). There were no cases of Onyx fixation of the device in the parent artery; no significant tension was required to remove the device after Onyx injection. This represents a significantly different experience from the typically used Onyx microcatheter (Marathon), which carries a known risk of tip-adhesion to the Onyx cast. We detail technical nuances used to maximise the benefits of the Scepter C™ for such applications. Conclusions The Scepter C balloon catheter has, thus far, proven to be a safe and effective device for the endovascular treatment of vascular malformations through Onyx embolisation. A larger prospective study should be undertaken to ascertain any potential advantages or disadvantages compared to the current standard delivery catheters. Disclosures S. Grupke: None. A. Alhajeri: None. J. Fraser: None.

Neurologic emergencies: case studies.

During the past 2 decades, the world has witnessed a significant improvement in the understanding of the pathogenesis and treatment of neurologic diseases, which presents emergencies. Every day neurologists are consulted for patients who present with neurologic emergencies to the emergency departments. In this article, we present a series of case reports about patients with acute neurologic and psychiatric problems and discuss their management briefly.