Cerebral emboli detection and autonomous neuromonitoring using robotic transcranial Doppler with artificial intelligence for transcatheter aortic valve replacement with and without embolic protection devices: a pilot study.

BACKGROUND: Periprocedural ischemic stroke remains a serious complication in patients undergoing transcatheter aortic valve replacement (TAVR). We used a novel robotic transcranial Doppler (TCD) system equipped with artificial intelligence (AI) for real-time continuous intraoperative neuromonitoring during TAVR to establish the safety and potential validity of this tool in detecting cerebral emboli, report the quantity and distribution of high intensity transient signals (HITS) with and without cerebral protection, and correlate HITS occurrence with various procedural steps. METHODS: Consecutive patients undergoing TAVR procedures during which the robotic system was used between October 2021 and May 2022 were prospectively enrolled in this pilot study. The robotic TCD system included autonomous adjustment of the TCD probes and AI-assisted post-processing of HITS and other cerebral flow parameters. Basic demographics and procedural details were recorded. Continuous variables were analyzed by a two-sample Mann-Whitney t-test and categorical variables by a χ2 or Fisher test. RESULTS: Thirty-one patients were prospectively enrolled (mean age 79.9±7.6 years; 16 men (51.6%)). Mean aortic valve stenotic area was 0.7 cm2 and mean aortic-ventricular gradient was 43 mmHg (IQR 31.5-50 mmHg). Cerebral protection was used in 16 cases (51.6%). Significantly fewer emboli were observed in the protection group than in the non-protection group (mean 470.38 vs 693.33; p=0.01). Emboli counts during valve positioning and implantation were significantly different in the protection and non-protection groups (mean 249.92 and 387.5, respectively; p=0.01). One (4%) transient ischemic attack occurred post-procedurally in the non-protection group. CONCLUSION: We describe a novel real-time intraoperative neuromonitoring tool used in patients undergoing TAVR. Significantly fewer HITS were detected with protection. Valve positioning-implantation was the most significant stage for intraprocedural HITS.

Interdisciplinary management of acute ischaemic stroke - current evidence on training requirements for endovascular stroke treatment. Position Paper from the ESC Council on Stroke and the European Association for Percutaneous Cardiovascular Interventions with the support of the European Board of Neurointervention: A step forward.

Stroke, a vascular disease of the brain, is the #1 cause of disability and a major cause of death worldwide. Stroke has a major negative impact on the life of stroke-affected individuals, their families and the society. A significant proportion of stroke victims indicate that would have preferred death over their after-stroke quality of life. Mechanical thrombectomy (MT), opening the occluded artery using mechanical aspiration or a thrombus-entrapment device, is a guideline-mandated (class I, level of evidence A) treatment modality in patients with large vessel occlusion stroke. MT clinical benefit magnitude indicates that a universal access to this treatment strategy should be the standard of care. Today there is a substantial geographic variation in MT deliverability, with large-scale disparities in MT implementation. In many countries effective access to MT remains severely limited. In addition, many of the MT-treated patients are treated too late for a good functional outcome because of logistic delays that include transportations to remotely located, scarce, comprehensive stroke centres. Position Paper from the European Society of Cardiology Council on Stroke and European Association for Percutaneous Cardiovascular Interventions on interdisciplinary management of acute ischaemic stroke, developed with the support of the European Board of Neurointervention fills an important gap in systematically enabling interventional cardiologists to support stroke intervention in the geographic areas of unmet needs in particular. We review strengths and weaknesses of the document, and suggest directions for the next steps that are swiftly needed to deliver MT to stroke patients more effectively.

Interdisciplinary management of acute ischaemic stroke: Current evidence training requirements for endovascular stroke treatment. Position Paper from the ESC Council on Stroke and the European Association for Percutaneous Cardiovascular Interventions with the support of the European Board of Neurointervention.

This ESC Council on Stroke/EAPCI/EBNI position paper summarizes recommendations for training of cardiologists in endovascular treatment of acute ischaemic stroke. Interventional cardiologists adequately trained to perform endovascular stroke interventions could complement stroke teams to provide the 24/7 on call duty and thus to increase timely access of stroke patients to endovascular treatment. The training requirements for interventional cardiologists to perform endovascular therapy are described in details and should be based on two main principles: (i) patient safety cannot be compromised, (ii) proper training of interventional cardiologists should be under supervision of and guaranteed by a qualified neurointerventionist and within the setting of a stroke team. Interdisciplinary cooperation based on common standards and professional consensus is the key to the quality improvement in stroke treatment.

Expanding the stroke team to include interventional cardiology.

Team-based care has been emphasized as a strategy to improve and optimize outcomes for broad groups of patients who have presented with often complex medical conditions including large vessel cerebral occlusion. Although neurointerventionalists from different specialties perform mechanical embolectomy, which has become the standard of care for large vessel cerebral occlusion, these specialties are limited by relatively low numbers typically concentrated in a small number of sites. In this single center experience, approximately 50 patients with large vessel stroke were transferred out of an emergency room to other centers despite the availability of an experienced cardiologist with extensive carotid experience. Such transfer strategies typically result in delays in receiving reperfusion and, therefore, may decrease the success rates and substantial improvement that can be obtained by patients in this setting. Trained interventional cardiologists in centers with limited 24/7/365 coverage could achieve rapid revascularization and reperfusion saving lives. In order to accommodate the need for treating these patients, carotid stent trained cardiologists should enter the arena, learn mechanical embolectomy, and be supported by their colleagues from other disciplines on acute stroke care teams.

Clinical Outcomes of On-Site Versus Off-Site Endovascular Stroke Interventions.

OBJECTIVES: The aim of this study was to assess whether offering local endovascular stroke therapy (EST) rather than transferring patients off-site to receive EST would improve outcomes. BACKGROUND: There are limited data to determine whether offering EST on-site rather than transferring patients to receive EST off-site improves clinical outcomes. METHODS: A large academic consortium database was queried to identify patients with acute ischemic stroke who received EST between October 2015 and September 2019. Primary endpoints were in-hospital mortality and poor functional outcomes. Secondary endpoints were major complications, length of stay, and cost. Baseline characteristics were adjusted for using propensity score matching and multivariate risk adjustment. RESULTS: A total of 22,193 patients with acute ischemic stroke who underwent EST (50.8% on-site, 49.2% off-site) were included. Mean ages were 67.9 ± 15.5 years and 68.4 ± 15.5 years, respectively (p = 0.03). In the propensity score matching analysis, mortality and poor functional outcomes were higher in the off-site EST group (14.7% vs. 11.2% and 40.7% vs. 35.9%, respectively; p < 0.001). In the risk-adjusted analyses with different models, in-hospital mortality and poor functional outcomes remained significantly higher in the off-site EST group. In the most comprehensive model (adjusting for age, sex, demographics, risk factors, tissue plasminogen activator use, and institutional EST volume), in-hospital mortality and poor functional outcomes were significantly higher in the off-site EST group, with odds ratios of 1.38 (95% confidence interval: 1.26 to 1.51) and 1.26 (95% confidence interval: 1.18 to 1.34), respectively (p < 0.001). The incidence of intracranial hemorrhage and mechanical ventilation was higher in the off-site group, but cost was higher in the on-site group in both the propensity score matching and risk-adjusted analyses. CONCLUSIONS: In contemporary U.S. practice, patients with acute ischemic stroke treated with EST on-site had lower in-hospital mortality and better functional outcomes compared with those transferred off-site for EST.

Factors influencing credentialing of interventionists in the CREST-2 trial.

BACKGROUND: The Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis Trial (CREST-2) is a pair of randomized trials assessing the relative efficacy of carotid revascularization in the setting of intensive medical management (IMM) in patients with asymptomatic high-grade atherosclerotic stenosis. One of the trials assesses IMM with or without carotid artery stenting (CAS). Given the low risk of stroke in nonrevascularized patients receiving IMM, it is essential that there be low periprocedural risk of stroke for CAS if it is to show incremental benefit. Thus, credentialing of interventionists to ensure excellence is vital. This analysis describes the protocol-driven approach to credentialing of CAS interventionists for CREST-2 and its outcomes. METHODS: To be eligible to perform stenting in CREST-2, interventionists needed to be credentialed on the basis of a detailed Interventional Management Committee (IMC) review of data from their last 25 consecutive cases during the past 24 months along with self-reported lifetime experience case numbers. When necessary, additional prospective cases performed in a companion registry were requested after webinar training. Here we review the IMC experience from the first formal meeting on March 21, 2014 through October 14, 2017. RESULTS: The IMC had 102 meetings, and 8311 cases submitted by 334 interventionists were evaluated. Most were either cardiologists or vascular surgeons, although no single specialty made up the majority of applicants. The median total experience was 130 cases (interquartile range [IQR], 75-266; range, 25-2500). Only 9% (30/334) of interventionists were approved at initial review; approval increased to 46% (153/334) after submission of new cases with added training and re-review. The median self-reported lifetime case experience for those approved was 211.5 (IQR, 100-350), and the median number of cases submitted for review was 30 (IQR, 27-35). The number of CAS procedures performed per month (case rate) was the only factor associated with approval during the initial cycle of review (P < .00001). CONCLUSIONS: Identification of interventionists who were deemed sufficiently skilled for CREST-2 has required substantial oversight and a controlled system to judge current skill level that controls for specialty-based practice variability, procedural experience, and periprocedural outcomes. High-volume interventionists, particularly those with more recent experience, were more likely to be approved to participate in CREST-2. Primary approval was not affected by operator specialty.

Quality Assurance for Carotid Stenting in the CREST-2 Registry.

BACKGROUND: The CREST-2 Registry (C2R) was approved by National Institute of Neurological Disorders and Stroke-National Institutes of Health in September 2014 with Centers for Medicare & Medicaid Services, U.S. Food and Drug Administration, and industry collaboration to enroll patients undergoing CAS. The registry credentials interventionists and promotes optimal patient selection, procedural-technique, and outcomes. OBJECTIVES: This study reports periprocedural outcomes in a cohort of carotid artery stenting (CAS) performed for asymptomatic and symptomatic carotid stenosis. METHODS: Asymptomatic patients with ≥70% and symptomatic patients with ≥50% carotid stenosis, ≤80 years of age, and at standard or high risk for carotid endarterectomy are eligible for enrollment. Interventionists are credentialed by a multispecialty committee that reviews experience, lesion selection, technique, and outcomes. The primary endpoint was a composite of stroke and death (S/D) in the 30-day periprocedural period. Myocardial infarction and access-site complications were assessed as secondary outcomes. RESULTS: As of December 2018, 187 interventionists from 98 sites in the United States performed 2,219 CAS procedures in 2,141 patients with primary atherosclerosis (78 were bilateral). The mean age of the cohort was 68 years, 65% were male, and 92% were white; 1,180 (55%) were for asymptomatic disease, and 961 (45%) were for symptomatic disease. All U.S. Food and Drug Administration-approved stents and embolic protection devices were represented. The 30-day rate of S/D was 1.4% for asymptomatic, 2.8% for symptomatic, and 2.0% for all patients. CONCLUSIONS: C2R is the first national registry for CAS cosponsored by federal and industry partners. CAS was performed by experienced operators using appropriate patient selection and optimal technique. In that setting, a broad group of interventionists achieved very low periprocedural S/D rates for asymptomatic and symptomatic patients.

Vascular Anatomy and Not Age is Responsible for Increased Risk of Complications in Symptomatic Elderly Patients Undergoing Carotid Artery Stenting.

BACKGROUND: Various studies have suggested that age ≥80 years is associated with a higher rate of complications after carotid artery stenting (CAS). The Buffalo Risk Assessment Scale (BRASS) predicts complications in symptomatic patients undergoing CAS. Application of the BRASS has shown the ability to improve patient selection. We used the BRASS system to evaluate whether the higher rate of complications associated with CAS in the elderly is related to vascular anatomy. METHODS: A retrospective review of CAS was performed at our institution over 7 years. Demographic information, anatomic characteristics, BRASS categorization, and outcome measures were compared between elderly (≥80 years) and younger patients (<80 years). RESULTS: The study included 447 patients: 335 patients (75%) <80 years and 112 patients (25%) ≥80 years. There were significantly more elderly patients in the high-risk BRASS category (P < 0.01), and more young patients in the low-risk BRASS category (P = 0.04). The complication rates in the 2 groups were similar. Older patients were more likely to harbor complex vascular anatomy: they had significantly higher rates of types II and III aortic arches (P = 0.01 and P < 0.01, respectively), higher percentage of tortuous carotid vessels (P < 0.01), and higher rates of hostile anatomy for deployment of distal embolic protection devices (P = 0.02). CONCLUSIONS: Complex vascular anatomy, rather than age, is the key factor behind the higher CAS-associated complication rate in the elderly. Complications can be avoided through proper patient selection and stratifying patients based on anatomic characteristics, which can be achieved through the BRASS scoring system.

Interventional Cardiology and Acute Stroke Care Going Forward: JACC Review Topic of the Week.

Stroke is a catastrophic event for patients and their families. Given the frequency of approximately 750,000 events annually with their associated morbidity and mortality, stroke has assumed increasing importance. Scientific study has identified several diseases categorized under the broad term of "stroke" that form the rationale for current treatment strategies. This paper reviews new information, especially on ischemic stroke (particularly large-vessel occlusions), which identifies the potential for new approaches that can dramatically improve outcome but will require the need to enhance and embrace the care team required to deliver optimal care and address current unmet clinical needs.

Neck Remnants and the Risk of Aneurysm Rupture After Endovascular Treatment With Coiling or Stent-Assisted Coiling: Much Ado About Nothing?

BACKGROUND: Neck remnants are not uncommon after endovascular treatment of cerebral aneurysms. Critics of endovascular treatments for cerebral aneurysms cite neck remnants as evidence in favor of microsurgical clipping. However, studies have failed to evaluate the true clinical significance of aneurysm neck remnants following endovascular therapies. OBJECTIVE: To assess the clinical significance of residual aneurysm necks and to determine the rate of subsequent rupture following coiling or stent-assisted coiling of cerebral aneurysms. METHODS: We retrospectively reviewed the records of 1292 aneurysm cases that underwent endovascular treatment at 4 institutions. Aneurysms treated by primary coiling or stent-assisted coiling were included in the study; those treated by flow diversion were excluded Aneurysms with residual filling (i.e., Raymond-Roy Occlusion Classification II, neck remnant; or III, residual aneurysm filling) were assessed for their risk of subsequent rupture. RESULTS: A total of 626 aneurysms were identified as having residual filling immediately posttreatment. Of these, 13 aneurysms (2.1%) ruptured during the follow-up period (mean 7.3 mo; range 1-84 mo). Eleven of the 13 (84.6%) were ruptured at presentation. Rupture at presentation, the size of the aneurysm, and the increasing age of the patient were predictive of posttreatment rupture. CONCLUSION: We found that unruptured aneurysms with residual necks following endovascular treatment posed a very low risk of rupture (0.6%). However, patients presenting with ruptured aneurysms had a higher risk of rerupture from a neck remnant (3.4%). These results highlight the importance of achieving complete angiographic occlusion of ruptured aneurysms.

Multicenter Study of Pipeline Flex for Intracranial Aneurysms.

BACKGROUND: The Pipeline Flex (PED Flex; Medtronic, Dublin, Ireland) was designed to facilitate deployment and navigation compared to its previous iteration to reduce the rate of technical events and complications. OBJECTIVE: To assess the neurological morbidity and mortality rates of the PED Flex at 30 d. METHODS: Information from 9 neurovascular centers was retrospectively obtained between July 2014 and March 2016. Data included patient/aneurysm characteristics, periprocedural events, clinical, and angiographic outcomes. Multivariate logistic regression was performed to determine predictors of unfavorable clinical outcome (modified Rankin Scale [mRS] > 2). RESULTS: A total of 205 patients harboring 223 aneurysms were analyzed. The 30-d neurological morbidity and mortality rates were 1.9% (4/205) and 0.5% (1/205), respectively. The rate of intraprocedural events without neurological morbidity was 6.8% (14/205), consisting of intraprocedural ischemic events in 9 patients (4.5%) and hemorrhage in 5 (2.4%). Other technical events included difficulty capturing the delivery wire in 1 case (0.5%) and device migration after deployment in another case (0.5%). Favorable clinical outcome (mRS 0-2) was achieved in 186 patients (94.4%) at discharge and in 140 patients (94.5%) at 30 d. We did not find predictors of clinical outcomes on multivariate analysis. CONCLUSION: The 30-d rates of neurological morbidity and mortality in this multicenter cohort using the PED Flex for the treatment of intracranial aneurysms were low, 1.9% (4/205) and 0.5% (1/205), respectively. In addition, technical events related to device deployment were also low, most likely due to the latest modifications in the delivery system.

Feasibility, safety, and changes in systolic blood pressure associated with endovascular revascularization of symptomatic and chronically occluded cervical internal carotid artery using a newly suggested radiographic classification of chronically occluded cervical internal carotid artery: pilot study.

OBJECTIVEThe overall risk of ischemic stroke from a chronically occluded internal carotid artery (COICA) is around 5%-7% per year despite receiving the best available medical therapy. Here, authors propose a radiographic classification of COICA that can be used as a guide to determine the technical success and safety of endovascular recanalization for symptomatic COICA and to assess the changes in systemic blood pressure following successful revascularization.METHODSThe radiographic images of 100 consecutive subjects with COICA were analyzed. A new classification of COICA was proposed based on the morphology, location of occlusion, and presence or absence of reconstitution of the distal ICA. The classification was used to predict successful revascularization in 32 symptomatic COICAs in 31 patients, five of whom were female (5/31 [16.13%]). Patients were included in the study if they had a COICA with ischemic symptoms refractory to medical therapy. Carotid artery occlusion was defined as 100% cross-sectional occlusion of the vessel lumen as documented on CTA or MRA and confirmed by digital subtraction angiography.RESULTSFour types (A-D) of radiographic COICA were identified. Types A and B were more amenable to safe revascularization than types C and D. Recanalization was successful at a rate of 68.75% (22/32 COICAs; type A: 8/8; type B: 8/8; type C: 4/8; type D: 2/8). The perioperative complication rate was 18.75% (6/32; type A: 0/8 [0%]; type B: 1/8 [12.50%]; type C: 3/8 [37.50%], type D: 2/8 [25.00%]). None of these complications led to permanent morbidity or death. Twenty (64.52%) of 31 subjects had improvement in their symptoms at the 2-6 months' follow-up. A statistically significant decrease in systolic blood pressure (SBP) was noted in 17/21 (80.95%) patients who had successful revascularization, which persisted on follow-up (p = 0.0001). The remaining 10 subjects in whom revascularization failed had no significant changes in SBP (p = 0.73).CONCLUSIONSThe pilot study suggested that our proposed classification of COICA may be useful as an adjunctive guide to determine the technical feasibility and safety of revascularization for symptomatic COICA using endovascular techniques. Additionally, successful revascularization may lead to a significant decrease in SBP postprocedure. A Phase 2b trial in larger cohorts to assess the efficacy of endovascular revascularization using our COICA classification is warranted.

Neuroendovascular Fellowship Training: Self-Assessment of a Program Accredited by the Committee on Advanced Subspecialty Training.

The University at Buffalo's neuroendovascular fellowship is one of the longest running fellowship programs in North America. The burgeoning neurointerventional workforce and the rapid growth in the neurointerventional space on the heels of groundbreaking clinical trials prompted us to assess the fellowship's academic impact and its graduates' perceptions and productivity. An anonymized web-based survey was sent to all former neuroendovascular fellows with specific questions pertaining to current practice, research and funding, and perceptions about the fellowship's impact on their skills, competitiveness, and compensation. Additionally, the h-index was calculated to assess the academic productivity of each graduated fellow. Among 50 former fellows, 42 (84%) completed the survey. The fellows came from various countries, ethnic backgrounds, and specialties including neurosurgery (n = 39, 93%), neurology (n = 2, 5%), and neuroradiology (n = 1, 2%). Twenty (48%) respondents were currently chairs or directors of their practice. Most (n = 30, 71%) spent at least 10% of their time on research activities, with 27 (64%) receiving research funding. The median h-index of all 50 former fellows was 14. The biggest gains from the fellowship were reported to be improvement in endovascular skills (median = 10 on a scale of 0-10 [highest]) and increase in competitiveness for jobs in vascular neurosurgery (median = 10), followed by increase in academic productivity (median = 8), and knowledge of vascular disease (median = 8). In an era with open calls for moratoriums on endovascular fellowships, concerns over market saturation, and pleas to improve training, fellowship programs perhaps merit a more objective assessment. The effectiveness of a fellowship program may best be measured by the academic impact and leadership roles of former fellows.

Better Outcomes and Reduced Hospitalization Cost are Associated with Ultra-Early Treatment of Ruptured Intracranial Aneurysms: A US Nationwide Data Sample Study.

BACKGROUND: The benefit of surgical treatment of ruptured aneurysms is well established. OBJECTIVE: To determine whether ultra-early ruptured aneurysm treatment leads to not only improved outcomes but also reduced hospitalization cost. METHODS: Using 2008-2011 Nationwide Inpatient Sample data, we analyzed demographic, clinical, and hospital factors for nontraumatic subarachnoid hemorrhage (SAH) patients who were "directly" admitted to the treating hospital where they underwent intervention (clipping/coiling). Patients treated on the day of admission (day 0) formed the ultra-early cohort; others formed the deferred treatment cohort. All Patient Refined Diagnosis-Related Groups were also included in regression analyses. RESULTS: A total of 17 412 patients were directly admitted to a hospital following nontraumatic SAH where they underwent intervention (clipping/coiling). Mean patient age was 53.87 yr (median 53.00, standard deviation 14.247); 68.3% were women (n = 11 893). A total of 6338 (36.4%) patients underwent treatment on the day of admission (ultra-early). Patients who underwent treatment on day 0 had significantly more routine discharge dispositions than those treated >admission day 0 (P < .0001). In regression analysis, treatment on day 0 was protective against other than routine discharge disposition outcome (P < .0001; odds ratio 0.657; 95% confidence interval 0.614-0.838). Total cost incurred by hospitals was $4.36 billion. Mean cost of hospital charges in the ultra-early cohort was $239 126.05, which was significantly lower than that for the cohort treated >day 0 ($272 989.56, P < .001), Mann-Whitney U-test). Performance of an intervention on admission day 0 was protective against higher hospitalization cost (P < .0001; odds ratio 0.811; 95% confidence interval 0.732-0.899). CONCLUSION: Ultra-early treatment of ruptured aneurysms is significantly associated with better discharge disposition and decreased hospitalization cost.

Initial Clinical Experience with AView-A Clinical Computational Platform for Intracranial Aneurysm Morphology, Hemodynamics, and Treatment Management.

BACKGROUND: The management of intracranial aneurysm (IA) is challenging. Clinicians often rely on varied and intuitively disparate ways of evaluating rupture risk that may only partially take into account complex hemodynamic and morphologic factors. We developed a prototype of a clinically oriented, streamlined, computational platform, AView, for rapid assessment of hemodynamics and morphometrics in clinical settings. To show the potential clinical utility of AView, we report our initial multicenter experience highlighting the possible advantages of morphologic and hemodynamic analysis of IAs. METHODS: AView software was deployed across 8 medical centers (6 in the United States, 2 in Japan). Eight clinicians were trained and used the AView software between September 2012 and January 2013. RESULTS: We present 12 illustrative cases that show the potential clinical utility of AView. For all, morphology and hemodynamics, flow visualization, and rupture resemblance score (a surrogate for rupture risk) were provided. In 3 cases, AView could confirm the clinicians' decision to treat; in 3 cases, it could suggest which aneurysms may be at greater risk among multiple aneurysms; in 5 cases, AView could provide additional information for use during treatment decisions for ambiguous situations. In one stent-assisted coiling case, flow visualization predicted that the intuitive choice for stent placement could have resulted in sacrifice of an anterior cerebral artery due to blockage by coils and led clinicians to reconsider treatment plans. CONCLUSIONS: AView has the potential to confirm decisions to treat IAs, suggest which among multiple aneurysms to treat, and guide treatment decisions. Furthermore, the flow visualization it affords can inform aneurysm treatment planning and potentially avoid poor outcomes.