MINT Registry: Rationale and Study Design

Background Mechanical thrombectomy has become the standard of care for treatment of acute ischemic stroke secondary to large‐vessel occlusion up to 24 hours from last known normal time. Multiple different techniques for mechanical thrombectomy have been described, including a direct aspiration first‐pass technique and stent retriever thrombectomy. With a direct aspiration first‐pass technique, classically, a large‐bore aspiration catheter is delivered over a microcatheter and microwire to the clot. Recently, a novel macrowire has been introduced as a potential alternative to the use of microwire–microcatheter to allow the delivery of the aspiration catheter. The aim of this study is to develop a multicenter registry comparing delivery of an aspiration catheter for intracranial thrombectomy for acute ischemic stroke secondary to emergent large‐vessel occlusion over a macrowire in comparison with traditional use of microcatheter and microwire. Methods MINT (Macrowire for Intracranial Thrombectomy) is a multicenter, observational study currently enrolling patients with large‐vessel occlusion who underwent mechanical thrombectomy using a macrowire to deliver the aspiration catheter to the intracranial occlusion. All the participating sites will screen and report cases on a monthly basis. The decision to use the macrowire and various aspiration catheters is at the discretion of the interventionalist. Results We will collect patient\u27s clinical, demographic, and radiographic data. In addition, we plan to collect procedure variables and postprocedure clinical and imaging data. Outcomes include successful delivery of the reperfusion catheter to the clot interface, time taken from groin access to first pass, and a bailout strategy for thrombectomy in cases where this is not feasible. Conclusion The MINT registry will add to our understanding of safety and efficacy of this novel macrowire in intracranial thrombectomy. This registry will also highlight and allow for understanding in workflow improvements from simplifying setup and possibly cost effectiveness of this technique

Comparison of thrombectomy alone versus bridging thrombolysis in a US population using regression discontinuity analysis

The role of intravenous thrombolysis (IVT) in combination with endovascular thrombectomy (EVT) for the treatment of large vessel occlusion acute ischemic stroke has been evaluated exclusively outside the US, in randomized clinical trials which failed to demonstrate non-inferiority of skipping IVT. Because practice patterns and IVT dosing differ within the US, and prior observational US-based cohorts suggested improved clinical outcomes in patients who received IVT before EVT, a US-based evaluation is needed. This is a quasi-experimental study of a large US cohort using a regression discontinuity design (RDD) that enables the estimation of causal effects when randomization is not feasible. In this multi-center prospective cohort of patients undergoing EVT, we observed a sharp drop (65%) in the probability of receiving IVT at the cutoff of IVT eligibility time window while there were no significant differences in potential confounders including age, NIHSS, and ASPECTS at the cutoff. We found no association between IVT treatment and functional independence (mRS 0–2) at 90-days in patients undergoing EVT, nor in the secondary outcomes of excellent outcomes (mRS 0–1) at 90 days, mortality, symptomatic intracranial hemorrhage, first pass reperfusion, or final reperfusion

Factors Affecting Selection of TraineE for Neurointervention (FASTEN)

BACKGROUND AND IMPORTANCE: Neurointervention is a very competitive specialty in the United States due to the limited number of training spots and the larger pool of applicants. The training standards are continuously updated to ensure solid training experiences. Factors affecting candidate(s) selection have not been fully established yet. Our study aims to investigate the factors influencing the selection process. METHODS: A 52-question survey was distributed to 93 program directors (PDs). The survey consisted of six categories: (a) Program characteristics, (b) Candidate demographics, (c) Educational credentials, (d) Personal traits, (e) Research and extracurricular activities, and (f) Overall final set of characteristics. The response rate was 59.1%. As per the programs\u27 characteristics, neurosurgery was the most involved specialty in running the training programs (69%). Regarding demographics, the need for visa sponsorship held the greatest prominence with a mean score of 5.9 [standard deviation (SD) 2.9]. For the educational credentials, being a graduate from a neurosurgical residency and the institution where the candidate\u27s residency training is/was scored the highest [5.4 (SD = 2.9), 5.4 (SD = 2.5), respectively]. Regarding the personal traits, assessment by faculty members achieved the highest score [8.9 (SD = 1)]. In terms of research/extracurricular activities, fluency in English had the highest score [7.2 (SD = 1.9)] followed by peer-reviewed/PubMed-indexed publications [6.4 (SD = 2.2)]. CONCLUSION: Our survey investigated the factors influencing the final decision when choosing the future neurointerventional trainee, including demographic, educational, research, and extracurricular activities, which might serve as valuable guidance for both applicants and programs to refine the selection process

Abstract 023: Early Medical Student Introduction to Interventional Neurology: Integrating Neuroendovascular Simulation to Foster Engagement

Introduction Interventional Neurology (IN) is a rapidly expanding field, with new devices and techniques broadening the range of cerebrovascular diseases that can be treated (1). Despite this, medical students are not commonly exposed to IN either during their preclinical years or neurology clerkship. Other reports have indicated significant interest in IN through neurology residency despite a poorly structured pathway to the career (2). There remains a paucity of educational focus on endovascular specialties among medical schools; simulation‐based approaches present an opportunity to address this (3‐5). We piloted an engaging didactic and hands‐on Mentice® Neuroendovascular simulation seminar to increase awareness and interest in IN. Methods Through the Student Interest Group in Neurology (SIGN) at Emory School of Medicine, we recruited 20 students (55% M1, 5% M2, 30% M3, 10% M4; 50% female) to participate in an IN didactic and simulation seminar. Before and after the seminar, participants were administered a 28‐question survey regarding their knowledge of and interest in a career in IN. All participants provided consent. A didactic session led by a fellowship trained Interventional Neurologist and a simulation session including 3 stations: diagnostic angiography, thrombectomy, and aneurysm coiling. All participants rotated at all 3 stations and all questions were answered. Results The survey was broken into subjective and objective questions regarding student interest, familiarity, and knowledge of IN. The subjective questions were recorded on Likert scales from 1‐5 while objective questions focused on endovascular procedures and their indications. Exposure to IN was limited; 70% of medical students reported no formal exposure to the field. Prior to the event, only 30% of students were interested or very interested (4 or 5 on Likert scales) in a career in IN compared to 50% post‐survey. 20% of students felt familiar or very familiar with the field prior to the seminar compared to 50% post‐survey. More students recognized the training pathways to Neurointervention (Radiology, Neurosurgery, and Neurology), could name at least 3 IN procedures, and showed improved knowledge of basic IN treatments and pathology after the event. Conclusion Interventional Neurology remains a relatively new field and is often not included in traditional medical student curriculums, even at sites where training occurs within a Comprehensive Stroke Center. Our survey demonstrated the lack of knowledge and comfort level regarding IN amongst medical students. Uniquely curated seminars targeted at medical students can lead to an increase in awareness and interest in IN (6‐8). Early exposure has been shown to increase recruitment and dispel erroneous assumptions about the specialty (4). We believe these survey results show the importance of incorporating lecture and simulation based IN procedures for medical students, especially those interested in procedural specialties. Increasing students’ knowledge of IN also provides a better understanding of career options in neurology and the extent of therapeutic options a neurologist can offer patients (2,4)

Comparing Outcome In Hemorrhagic Transformation After Intravenous Thrombolysis Between In-house and Outside Hospital Treatment

Introduction: Intravenous thrombolysis (alteplase) is now standard of care in patients with acute ischemic stroke within 4.5 hours. Approximately 5-6 % of patients developed hemorrhagic transformation after alteplase; out of which 1-2 % have severe bleed resulting in death. Many factors leading to poor outcome higher NIHSS, time of symptom onset to need time, High blood glucose, elevated BP etc. Hypothesis: In this study we aim to compare the outcome between In-House alteplase vs patients receiving alteplase Outside hospital and later transferred, eventually develops hemorrhagic transformation. Methods: We analyzed patients who received thrombolysis from June 2015 to June 2016 through Electronic Medical records. Hemorrhagic transformation grading scale used in Berger C, 2001, Stroke. BP cutoff was set at >180/100 systolic post alteplase. Two groups were compared In-House and Outside transfers. Results: There were total 18 patients (In-House 10 and 8 Outside) who developed hemorrhagic transformation out of 154 patients who received alteplase in one year. Average symptom onset to needle time/ initial NIHSS was higher (196min/20) in In-House group vs Outside (142 min/16) respectively. However, discharge NIHSS and MRS was noted to be higher in Outside group by 11 points and 1 point respectively. Whereas, average duration of hospital stay was higher in In-House group by 4 days. Both groups noted to have similar BP elevation (60%) suggesting BP as important indicator for hemorrhagic transformation. Mortality rate was higher in Outside group at 60% (higher Hemorrhagic Scale) compared to 30 % in In-House group, although same percentage (60) of BP elevation was noted in both groups. The better outcome in In-house group could be attributed to higher percentage of successful intervention in In-House group (50%) vs Outside (12%). Conclusion: Patients who received alteplase In-House, saw a lower percentage of fatal hemorrhagic transformation and overall better morbidity rate likely from faster and timely successful intervention.</p

Abstract 228: Suboptimal Door‐to‐Puncture Times: Challenges Faced in the Stroke Alert Workflow

Introduction Advances in stroke care have led to more patients eligible for thrombectomy. With these advances, it has become imperative to create a seamless workflow for thrombectomy candidates to ensure rapid door‐to‐puncture times and, ultimately, improve patient outcomes. We sought to determine what barriers are causing delays in patients’ door‐to‐puncture time. Methods A survey was distributed to all members of the Neurology PGY2, PGY3, PGY4 classes and vascular fellows at our single‐center, Comprehensive Stroke Center. The survey allowed participants to freely respond to questions regarding obstacles they encountered that led to delays in door‐to‐puncture times. All survey responses were anonymized. Results The survey was sent to 32 participants, with 26 responses. Of the 26 responses, 11 respondents (42%) noted that obtaining IV access for CTA/CTP scans was a significant cause of delay. Other responses included lack of availability of family for collateral (23%), CT scanner availability (15%), and length of time to decide if the patient is a thrombectomy candidate (15%). Conclusion The goal of this study was to collect data from the individuals involved in the direct care of acute stroke patients who are thrombectomy candidates. We used their experience to determine which points in the stroke alert workflow led to delays in door‐to‐puncture time. Our survey showed the most consistent delay is obtaining proper IV access for CTA and CTP imaging. This information was valuable and has led to the creation of a coalition between the neurology and emergency medicine departments, nursing, and CT technologists to create a “CODE IV” protocol to be implemented into the stroke alert workflow. We aim to report the change in door‐to‐puncture time after the implementation of this new protocol