Search

Background Most conventional 0.088 inch guide catheters cannot safely navigate intracranial vasculature. The objective of this study is to evaluate the safety of stroke thrombectomy using a novel 0.088 inch guide catheter designed for intracranial navigation. Methods This is a multicenter retrospective study, which included patients over 18 years old who underwent thrombectomy for anterior circulation large vessel occlusions. Technical outcomes for patients treated using the TracStar Large Distal Platform (TracStar LDP) or earlier generation TRX LDP were compared with a matched cohort of patients treated with other commonly used guide catheters. The primary outcome measure was device-related complications. Secondary outcome measures included guide catheter failure and time between groin puncture and clot engagement. Results Each study arm included 45 patients. The TracStar group was non-inferior to the control group with regard to device-related complications (6.8% vs 8.9%), and the average time to clot engagement was 8.89 min shorter (14.29 vs 23.18 min; p=0.0017). There were no statistically significant differences with regard to other technical outcomes, including time to recanalization (modified Thrombolysis In Cerebral Infarction (mTICI) ≥2B). The TracStar was successfully advanced into the intracranial internal carotid artery in 33 cases (73.33%); in three cases (6.67%), it was swapped for an alternate catheter. Successful reperfusion (mTICI 2B-3) was achieved in 95.56% of cases. Ninety-day follow-up data were available for 86.67% of patients, among whom 46.15% had an modified Rankin Score of 0--2%, and 10.26% were deceased. Conclusions Tracstar LDP is safe for use during stroke thrombectomy and was associated with decreased time to clot engagement. Intracranial access was regularly achieved. [ABSTRACT FROM AUTHOR]

Background Over the past several years there has been increased interest in the use of the Sofia aspiration system (MicroVention, Tustin, California) as a primary aspiration catheter. Objective To perform a multicenter retrospective study examining the efficacy of the Sofia aspiration catheter as a standalone aspiration treatment for large vessel occlusion. Methods Consecutive cases in which the Sofia catheter was used for aspiration thrombectomy for large vessel occlusion were included. Exclusion criteria were the following: (1) Sofia not used for first pass, and (2) a stent retriever used as an adjunct on the first pass. The primary outcome of the study was first pass recanalization (Thrombolysis in Cerebral Infarction (TICI) 2c/3). Secondary outcomes included first pass TICI 2b/3, crossover to other thrombectomy devices, number of passes, time from puncture to recanalization, and complications. Results 323 patients were included. First pass TICI 2c/3 was achieved in 49.8% of cases (161/323). First pass TICI 2b/3 was achieved in 69.7% (225/323) of cases. 74.8% had TICI 2b/3 with the Sofia alone. Crossover to other thrombectomy devices occurred in 29.1% of cases (94/323). The median number of passes was 1 (IQR=1-3). Median time from puncture to recanalization was 26 min (IQR=17-45). Procedure related complications occurred in 3.1% (10/323) of cases. Conclusion Our study highlights the potential advantage of the Sofia aspiration catheter for primary aspiration thrombectomy in acute ischemic stroke. High rates of first pass recanalization with low crossover rates to other thrombectomy devices were achieved. Median procedure time was low, as were procedural complications. [ABSTRACT FROM AUTHOR]

Background It has been reported that longer time intervals from stroke onset to endovascular therapy are associated with lower rates of successful reperfusion in acute ischemic stroke patients with large vessel occlusion. However, procedural variables and potential mechanisms of this association have not been fully elucidated. Methods We performed a secondary analysis of individual patient data from the North American Solitaire Stent Retriever Acute Stroke (NASA) and Trevo Stent- Retriever Acute Stroke (TRACK) registries. We included patients with occlusion of the internal carotid artery or middle cerebral artery (M1 and M2 segments) who were treated by mechanical thrombectomy within 24 hours of last known normal. The primary outcome was reperfusion, defined as a Thrombolysis In Cerebral Infarction (TICI) score ≥2b. The secondary outcome was reperfusion on the first pass. The primary predictor was duration of symptomatic stroke, defined as time from last known normal to time of final pass. Adjusted logistic regression models were utilized to determine associations between variables and outcome. Results We included 506 patients, of which 401 (79.3%) achieved successful reperfusion (TICI 2b/3). The mean (SD) duration of symptomatic stroke was 6.8 (3.5) hours and in the adjusted logistic regression model the duration of symptomatic stroke was associated with reperfusion (OR 0.90, 95% CI 0.84 to 0.96) and reperfusion on the first pass (OR 0.89, 95% CI 0.83 to 0.95). In that model, the predicted probability of reperfusion was 88% (95% CI 0.83 to 0.92) at 1 hour, 81% (95% CI 0.78 to 0.84) at 6 hours, 70% (95% CI 0.63 to 0.77) at 12 hours, and 42% (95% CI 0.17 to 0.67) at 24 hours (ptrend=0.001). Reperfused patients were significantly younger, more likely to be male, and to have had a balloon guide catheter used during the procedure. Conclusion In a real- world cohort of acute ischemic stroke patients with anterior circulation occlusion treated with endovascular therapy, longer duration of symptomatic stroke is associated with lower rates of successful reperfusion and reperfusion on the first pass. [ABSTRACT FROM AUTHOR]

Purpose: Intra-procedural assessment of reperfusion during mechanical thrombectomy (MT) for emergent large vessel occlusion (LVO) stroke is traditionally based on subjective evaluation of digital subtraction angiography (DSA). However, semi-quantitative diagnostic tools which encode hemodynamic properties in DSAs, such as angiographic parametric imaging (API), exist and may be used for evaluation of reperfusion during MT. The objective of this study was to use data-driven approaches, such as convolutional neural networks (CNNs) with API maps, to automatically assess reperfusion in the neuro-vasculature during MT procedures based on the modified thrombolysis in cerebral infarction (mTICI) scale. Methods: DSAs from patients undergoing MTs of anterior circulation LVOs were collected, temporally cropped to isolate late arterial and capillary phases, and quantified using API peak height (PH) maps. PH maps were normalized to reduce injection variability. A CNN was developed, trained, and tested to classify PH maps into 2 outcomes (mTICI 0,1,2a/mTICI 2b,2c,3) or 3 outcomes (mTICI 0,1,2a/mTICI 2b/mTICI 2c,3), respectively. Ensembled networks were used to combine information from multiple views (anteroposterior and lateral). Results: The study included 383 DSAs. For the 2-outcome classification, average accuracy was 81.0% (95% CI, 79.0–82.9%), and the area under the receiver operating characteristic curve (AUROC) was 0.86 (0.84–0.88). For the 3-outcome classification, average accuracy was 64.0% (62.0–66.0), and AUROC values were 0.85 (0.83–0.87), 0.74 (0.71–0.77), and 0.78 (0.76–0.81) for the mTICI 0,1,2a, mTICI 2b, and mTICI 2c,3 classes, respectively. Conclusion: This study demonstrated the feasibility of using hemodynamic information in API maps with data-driven models to autonomously assess intra-procedural reperfusion during MT. [ABSTRACT FROM AUTHOR]

Background Clot density (Hounsfield units, HU) and perviousness (post- contrast increase in the HU of clot) are thought to be associated with clot composition. We evaluate whether these imaging characteristics were associated with angiographic outcomes of aspiration and stent retriever thrombectomy in COMPASS: a trial of aspiration thrombectomy versus stent retriever thrombectomy as first- line approach for large vessel occlusion. Methods Clot density and perviousness were measured by two independent operators who were blind to all the final angiographic and clinical outcomes. The association of clot density and perviousness with the Thrombolysis In Cerebral Infarction (TICI) scale after first pass was assessed using univariate and multivariate analysis. Results Among all patients enrolled in COMPASS, 165 were eligible for the post- hoc analysis (81 patients in the aspiration first and 84 in the stent retriever first groups). Overall mean perviousness of clot was significantly higher in patient with mTICI 2b-3 after first pass (28.6±22.9 vs 20.3±19.2, p=0.017). Mean perviousness among patients who achieved TICI 2c/3 versus TICI 2b versus TICI 0- 2a in the aspiration first group varied significantly (32.6±26.1, 35.3±24.4, and 17.7±13.1, p=0.013). The association of perviousness with first pass success was not significant in the stent retriever group. Using multivariate analysis, high perviousness (defined as cut- off >27.6) was an independent predictor of TICI 2b-3 (OR 3.82, 95% CI 1.10 to 13.19; p=0.034). Conclusions Clot perviousness is associated with first pass angiographic success in patients treated with the aspiration first approach for thrombectomy. [ABSTRACT FROM AUTHOR]

Purpose: Few studies have examined the geometry of endovascular mechanical thrombectomy pathways. Here we examine the tortuosity and angulations of catheter pathways from the aortic arch to the termination of the internal carotid artery (ICA) and its association with thrombectomy performance. Methods: We included 100 consecutive anterior circulation large vessel occlusion thrombectomy patients over 12 months. Computed tomography angiograms (CTA) were used for 3D segmentation of catheter pathway from the aortic arch to ICA termination. Tortuosity index (TI) and angulations of the catheter pathway were measured in a semi-automated fashion. TI and angulation degree were compared between sides and correlated with age and procedural measures. Results: We analyzed 188 catheter pathways in 100 patients. Severe angulation (≤ 30°) was present in 5.8% and 39.4% of common carotid artery (CCA) and extracranial ICA segments, respectively. Five pathways (2.6%) had 360° loop. CCA and extracranial ICA tortuosity had a weak but significant correlation with age (r = 0.17, 0.21, p value = 0.05, 0.02 respectively), time from groin puncture to the site of occlusion (r = 0.29, 0.25, p values = 0.008, 0.026 respectively), and fluoroscopy time (r = 0.022, 0.31, p values = 0.016, 0.001 respectively). There was a significant difference in the pattern of angulation (p value = 0.04) and tortuosity between right and left side in CCA segment (TI = 0.20 ± 0.086 vs. 0.15 ± 0.82, p value < 0.001). Conclusions: There was a significant difference in CCA angulation between right and left sides. TI of extracranial CCA and ICA correlated with age and influenced time from groin puncture to the occlusion site and total fluoroscopy time. [ABSTRACT FROM AUTHOR]

background CT perfusion (CTP) infarct and penumbra estimations determine the eligibility of patients with acute ischemic stroke (AIS) for endovascular intervention. This study aimed to determine volumetric and spatial agreement of predicted RAPID, Vitrea, and Sphere CTP infarct with follow- up fluid attenuation inversion recovery (FLAIR) MRI infarct. Methods 108 consecutive patients with AIS and large vessel occlusion were included in the study between April 2019 and January 2020 . Patients were divided into two groups: endovascular intervention (n=58) and conservative treatment (n=50). Intervention patients were treated with mechanical thrombectomy and achieved successful reperfusion (Thrombolysis in Cerebral Infarction 2b/2 c/3) while patients in the conservative treatment group did not receive mechanical thrombectomy or intravenous thrombolysis. Intervention and conservative treatment patients were included to assess infarct and penumbra estimations, respectively. It was assumed that in all patients treated conservatively, penumbra converted to infarct. CTP infarct and penumbra volumes were segmented from RAPID, Vitrea, and Sphere to assess volumetric and spatial agreement with follow- up FLAIR MRI. results Mean infarct differences (95% CIs) between each CTP software and FLAIR MRI for each cohort were: intervention cohort: RAPID=9.0±7.7 mL, Sphere=0.2±8.7 mL, Vitrea=-7.9±8.9 mL; conservative treatment cohort: RAPID=-31.9±21.6 mL, Sphere=-26.8±17.4 mL, Vitrea=-15.3±13.7 mL. Overlap and Dice coefficients for predicted infarct were (overlap, Dice): intervention cohort: RAPID=(0.57, 0.44), Sphere=(0.68, 0.60), Vitrea=(0.70, 0.60); conservative treatment cohort: RAPID=(0.71, 0.56), Sphere=(0.73, 0.60), Vitrea=(0.72, 0.64). Conclusions Sphere proved the most accurate in patients who had intervention infarct assessment as Vitrea and RAPID overestimated and underestimated infarct, respectively. Vitrea proved the most accurate in penumbra assessment for patients treated conservatively although all software overestimated penumbra. [ABSTRACT FROM AUTHOR]

Background Burnout takes a heavy toll on healthcare providers. We sought to assess the prevalence and risk factors for burnout among neurointerventional (ni) non-physician procedural staff (nurses and technologists) given increasing thrombectomy demands. Methods a 41-question online survey containing questions including the Maslach Burnout inventory-human services survey for Medical Personnel was distributed to NI nurses and radiology technologists at 20 Us endovascular capable stroke centers. results 244 responses were received (64% response rate). Median (IQR) composite scores for emotional exhaustion were 25 (15-35), depersonalization 6 (2-11), and personal accomplishment 39 (35-43). Fifty-one percent of respondents met established criteria for burnout. There was no significant relationship between hospital thrombectomy volume, call frequency, call cases covered, or length of commute. On multiple logistic regression analysis, feeling under-appreciated by hospital leadership (Or 4.1; P<0.001) and working with difficult/ unpleasant physicians (Or 1.2; P=0.05) were strongly associated with burnout. at participating centers, nurse and technologist attrition was 25% over the previous year. Over 50% of respondents indicated they had strongly considered leaving their position over the last 2 years. Conclusions This survey of Us ni non-physician procedural staff demonstrates a self-reported burnout prevalence of 51%. This was driven more by interaction with leadership and physician staff than by thrombectomy procedural volume and stroke call. attrition among ni non-physician procedural staff is high. [ABSTRACT FROM AUTHOR]

Background Little is currently known about the effects of the coronavirus (COVID-19) pandemic on neurointerventional (NI) procedural volumes or its toll on physician wellness. Methods A 37- question online survey was designed and distributed to physician members of three NI physician organizations. Results A total of 151 individual survey responses were obtained. Reduced mechanical thrombectomy procedures compared with pre- pandemic were observed with 32% reporting a greater than 50% reduction in thrombectomy volumes. In concert with most (76%) reporting at least a 25% reduction in non- mechanical thrombectomy urgent NI procedures and a nearly unanimous (96%) cessation of non- urgent elective cases, 68% of physicians reported dramatic reductions (>50%) in overall NI procedural volume compared with pre- pandemic. Increased door- to- puncture times were reported by 79%. COVID-19- positive infections occurred in 1% of physician respondents: an additional 8% quarantined for suspected infection. Sixty- six percent of respondents reported increased career stress, 56% increased personal life/family stress, and 35% increased career burnout. Stress was significantly increased in physicians with COVID- positive family members (P<0.05). Conclusions This is the first study designed to understand the effects of the COVID-19 pandemic on NI physician practices, case volumes, compensation, personal/family stresses, and work- related burnout. Future studies examining these factors following the resumption of elective cases and relaxing of social distancing measures will be necessary to better understand these phenomena. [ABSTRACT FROM AUTHOR]

Introduction With the expansion of the interventional time window for stroke from emergent large vessel occlusion (ELVO), the rate of mechanical thrombectomy (MT) is expected to rise, potentially causing higher burnout rates and requiring hospitals to develop strategies for adequate coverage of these procedures. Methods Neurointerventional physicians at 10 participating stroke centers prospectively recorded time requirements for all MT consultations over 30 consecutive 24- hour call periods, including both false positive consultations and MT procedures, during mid to late 2018. Consult start time, procedure start and end time, and data regarding commute to the hospital and delay in scheduled procedures were collected and compared with those from an identical prospective study performed in 2017. Results Data were collected from a total of 300 days of call. a total of 166 procedures were performed (mean 0.55 per day), an increase from 0.32 per day in 2017. Overall mean MT direct time burden during each 24- hour call was 124 min (compared with 85 min in 2017). The percentage of consultations for thrombectomy varied based on time of day, with 87% of consults between the hours of midnight and 04:00 proceeding to thrombectomy compared with 37% between the hours of 16:00 and 20:00. Conclusions MT procedural volumes have increased from one every 5 days in 2016 to one every 2 days in 2018. The highest percentage of consults leading to thrombectomy occur in the early morning hours after midnight. compared with similar data from 2016 and 2017, call demands continue to escalate, representing a significant demand on neurointerventional teams. [ABSTRACT FROM AUTHOR]

Background The DeFUse 3 and DaWn trials have shown the benefit of thrombectomy beyond 6 hours of stroke symptom onset in carefully selected patients. Objective To evaluate the real-world outcomes of stent retriever thrombectomy beyond 6 hours of stroke onset using combined individual patient data from the north american solitaire stent retriever acute stroke (nasa) and Trevo stent-retriever acute stroke (TracK) registries. Methods Pooled analysis of individual patient data of all cases of anterior circulation acute ischemic stroke (ais) from nasa and TracK was performed to compare outcomes of patients presenting within the first hours 6 or beyond 6 hours of stroke symptom onset. results Of 830 patients with anterior circulation ais from the nasa and TracK registries, 32.7% (271 patients) underwent thrombectomy beyond the first 6 hours of symptom onset. The rates of good clinical outcome (modified rankin scale score of 0--2 at 90 days), mortality, and symptomatic intracranial hemorrhage were similar: 48.1%, 20.6%, and 8.0% within 0--6 hours, 46.2%, 21.6%, and 10.9% within 6--16 hours, and 38.9%, 33.3%, and 5% within 16--24 hours (p=0.8, 0.6, and 0.5, respectively). The rates of successful recanalization (Thrombolysis in cerebral infarction 2b/3) were 79.4% in patients with stroke within 0--6 hours, 72.6% within 6--16 hours, and 85.0% within 16--24 hours (p=0.04). Conclusions real-world experience with patients with anterior circulation ais treated with the solitaire and Trevo thrombectomy devices beyond the first 6 hours of symptom onset proved to be equally safe and effective as for patients with symptom onset within the first 6 hours. [ABSTRACT FROM AUTHOR]

Introduction Neurothrombectomy frequency is increasing, and a better understanding of the neurothrombectomy call burden is needed. Methods Neurointerventional physicians at nine participating stroke centers prospectively recorded time requirements for all neurothrombectomy (NT) consultations over 30 consecutive 24 hour call periods. Results Data were collected from a total of 270 days of call. 214 NT consultations were reported (mean 0.79 per day), including 130 'false positive' consultations that ultimately did not lead to thrombectomy (mean 0.48 per day). 84 NT procedures were performed at the nine centers (0.32 per day, or 1 every 3 days). Most (59.8%) consultations occurred between 5pm and 7am. 30% of thrombectomy procedures resulted in delays in scheduled cases; treating physicians had to emergently travel to the hospital for 51.2% of these cases. A median of 27 min was spent on each false positive consultation and 171 min on each thrombectomy. Overall, the median physician time spent on NT responsibilities per 24 hour call period was 69 min (mean 85 min; iQR 16-135 min). Conclusions NT consultations are frequent and often disrupt physician schedules, requiring physicians to commute in from home after hours in the majority of cases. As procedural and consultation volumes increase, it is crucial to understand the significant burden of call on neurointerventional physicians and develop strategies that reduce the potential for burnout. importantly, this study was performed prior to the completion of the DAWN and DEFUSE3 trials; NT consultations are expected to continue to increase in the future. [ABSTRACT FROM AUTHOR]

Background The development of new revascularization devices has improved recanalization rates and time but not clinical outcomes. We report our initial results with a new technique utilizing a direct aspiration first pass technique with a large bore aspiration catheter as the primary method for vessel recanalization. Methods A retrospective evaluation of a prospectively captured database of 37 patients at six institutions was performed on patients where the ADAPT technique was utilized. The data represent the initial experience with this technique. Results The ADAPT technique alone was successful in 28 of 37 (75%) cases although six cases had large downstream emboli that required additional aspiration. Nine cases required the additional use of a stent retriever and one case required the addition of a Penumbra aspiration separator to achieve recanalization. The average time from groin puncture to at least Thrombolysis in Cerebral Ischemia (TICI) 2b recanalization was 28.1 min, and all cases were successfully revascularized. TICI 3 recanalization was achieved 65% of the time. On average, patients presented with an admitting National Institutes of Health Stroke Scale (NIHSS) score of 16.3 and improved to an NIHSS score of 4.2 by the time of hospital discharge. There was one procedural complication. Discussion This initial experience highlights the fact that the importance of the technique with which new stroke thrombectomy devices are used may be as crucial as the device itself. The ADAPT technique is a simple and effective approach to acute ischemic stroke thrombectomy. Utilizing the latest generation of large bore aspiration catheters in this fashion has allowed us to achieve excellent clinical and angiographic outcomes. [ABSTRACT FROM AUTHOR]

Background The development of new revascularization devices has improved recanalization rates and time, but not clinical outcomes. We report a prospectively collected clinical experience with a new technique utilizing a direct aspiration first pass technique with large bore aspiration catheter as the primary method for vessel recanalization. Methods 98 prospectively identified acute ischemic stroke patients with 100 occluded large cerebral vessels at six institutions were included in the study. The ADAPT technique was utilized in all patients. Procedural and clinical data were captured for analysis. Results The aspiration component of the ADAPT technique alone was successful in achieving Thrombolysis in Cerebral Infarction (TICI) 2b or 3 revascularization in 78% of cases. The additional use of stent retrievers improved the TICI 2b/3 revascularization rate to 95%. The average time from groin puncture to at least TICI 2b recanalization was 37 min. A 5MAX demonstrated similar success to a 5MAX ACE in achieving TICI 2b/3 revascularization alone (75% vs 82%, p=0.43). Patients presented with an admitting median National Institutes of Health Stroke Scale (NIHSS) score of 17.0 (12.0-21.0) and improved to a median NIHSS score at discharge of 7.3 (1.0-11.0). Ninety day functional outcomes were 40% (modified Rankin Scale (mRS) 0-2) and 20% (mRS 6). There were two procedural complications and no symptomatic intracerebral hemorrhages. Discussion The ADAPT technique is a fast, safe, simple, and effective method that has facilitated our approach to acute ischemic stroke thrombectomy by utilizing the latest generation of large bore aspiration catheters to achieve previously unparalleled angiographic outcomes. [ABSTRACT FROM AUTHOR]

Introduction There are few published data evaluating the incidence of mechanical thrombectomy among stroke centers or the times at which they occur. Methods A multicenter retrospective study was performed to identify all patients undergoing emergent thrombectomy for acute ischemic stroke during a 3-month period (June through August 2016). Consultations that did not undergo thrombectomy were not included. Results Ten institutions participated in the study. During the 92-day study period, a total of 189 patients underwent mechanical thrombectomy. The average number of procedures per hospital over the study period was 18.9 (average of 0.2 cases per day per or 75.6 cases per year). This ranged from 0.09 cases per day at the lowest volume center to 0.49 cases per day at the highest volume center. Procedures were more common on weekdays (p<0.001) and during non-work hours (p<0.001). The most common period for thrombectomy procedures was between 20:00 and 21:00 hours. The median time from notification to groin puncture was 84 min (IQR 56-145 min) and from puncture to closure was 57 min (IQR 33-80 min). The median time from imaging completion to procedural start was 52 min longer for non-work hours than during work hours (p<0.001). There were no differences in procedural length based on day of the week or time of day. Conclusions These findings indicate that the majority of mechanical thrombectomy cases occur during non-work hours, with associated off-hours delays, which has important operational implications for hospitals implementing stroke call coverage. [ABSTRACT FROM AUTHOR]

Background The clot burden score (CBS) was developed as a tool to evaluate the extent of intracranial thrombus burden in patients with anterior circulation acute ischemic stroke. CBS is based on the presence or absence of contrast opacification on CT angiography (CTA). Its value in predicting radiographic and clinical outcomes in patients given endovascular stroke therapy remains unknown. Objective To evaluate the relationship between CBS and outcomes after stent retriever thrombectomy in the interventional arm of the SWIFT PRIME trial. Methods CBS was calculated for the endovascular arm (IV tissue plasminogen activator plus Solitaire stent retriever) of SWIFT PRIME using baseline CTA. The cohort of 69 patients was divided into three groups according to their CBS values: CBS 0-5 (n=14), CBS 6-7 (n=23), and CBS 8-9 (n=32). Results The mean age of the 69 patients who formed the study cohort was 63.2±13.1 years, mean National Institutes of Health Stroke Scale score was 16.8±4.5, and 55% of the patients were male. There was no difference in clinical characteristics among the three groups, except for the baseline Alberta Stroke Program Early CT Score (p=0.049). The site of proximal occlusion varied significantly among the three groups (p<0.001). Rates of successful recanalization (TICI 2b/3), complete recanalization (TICI 3 only) and of good clinical outcome at 3 months were similar among the three groups (p=0.24, p=0.35, and p=0.52, respectively). Conclusions The combination of IV thrombolysis and stent retriever thrombectomy with the Solitaire device is highly effective in achieving successful recanalization and a good clinical outcome throughout the entire range of CBS values. [ABSTRACT FROM AUTHOR]

Background Vessel perforation during stent retriever thrombectomy is a rare complication; typically only single instances have been reported. Objective To report on a series of patients whose stent retriever thrombectomy was complicated by intraprocedural vessel perforation and discuss its potential mechanisms, rescue treatment strategies, and clinical significance. Methods Cases with intraprocedural vessel perforation, where a stent retriever was used either as a primary treatment approach or as a part of a direct aspiration first pass technique (ADAPT), were included in the final analysis. Clinical data, procedural details, radiographic and clinical outcomes were collected from nine participating centers. Results Intraprocedural vessel perforation during stent retriever thrombectomy occurred in 16 (1.0%) of 1599 cases. 63% of intraprocedural perforations occurred at distal locations. Endovascular rescue techniques (most commonly, intracranial balloon occlusion for tamponade) were attempted in 50% of cases. Procedure was aborted without any rescue attempts in 44% of cases. Mortality during hospitalization and at 3 months was 56% and 63%, respectively. 25% of patients achieved good functional outcome at 3 months after the procedure. Conclusions Intraprocedural perforations during stent retriever thrombectomy were rare, but when they occurred were associated with high mortality. Perforations most commonly occurred at distal occlusion sites and were often characterized by difficulty traversing the occlusion with a microcatheter or microwire, or while withdrawing the stent retriever. Nevertheless, 25% of patients had a favorable functional outcome, suggesting that in some patients with this complication good neurological recovery is achievable. [ABSTRACT FROM AUTHOR]

Background Recently, an in vitro cerebrovascular occlusion model of the intracranial circulation was developed for testing thrombectomy devices. The Cover accessory (Lazarus Effect; Campbell, California, USA) is a novel nitinol braided mesh device that surrounds the stent retrieval device and thrombus during the retrieval process to help prevent clot fragmentation and embolization. Methods Using the in vitro model, after introducing fresh clot into the middle cerebral artery, we compared rates of target vessel recanalization and embolization in new territories (areas in which clot had not been introduced) achieved with the Solitaire Flow Restoration (FR) stent retriever (Covidien, Irvine, California) in conjunction with the use of a conventional guide catheter (control group), a balloon guide catheter (BGC group), and the Cover device (Cover group). Results In a total of 51 thrombectomy experiments (20 in the control group, 20 in the BGC group, and 11 in the Cover group), successful recanalization (Thrombolysis in Cerebral Infarction 2b-3) was achieved more frequently in the Cover group than in the control group or in the BGC group (p=0.047 and p=0.020, respectively). Embolization of new (previously unaffected) territories occurred in five (25%) experiments from the control group and in three (15%) experiments from the BGC group, whereas no embolization of new territories was seen with Cover device assisted thrombectomy. Conclusions Application of the Cover device in this experimental model resulted in higher successful recanalization rates, no embolic events, and was more effective than use of the conventional guide catheter or BGC. [ABSTRACT FROM AUTHOR]

Background Endovascular treatment of wake-up strokes (WUS) has been previously described, mostly with the use of pharmacological thrombolysis or first generation thrombectomy devices. Objective To describe outcomes of WUS treated with modern endovascular therapy since the Food and Drug Administration approval of stent retrievers, and to identify predictors of good clinical outcome in this population of stroke patients. Methods We performed a multicenter retrospective analysis of consecutive patients with WUS who underwent thrombectomy with stent retrievers Trevo (Stryker, Kalamazoo, Michigan, USA) and Solitaire FR (Covidien, Irvine, California, USA), or primary aspiration thrombectomy. We correlated favorable clinical outcomes with demographic, clinical, and technical characteristics. Results 52 patients were included in this study; 46 (88%) cases were treated with stent retrievers and 6 (12%) were treated with primary aspiration thrombectomy alone. Successful recanalization (Thrombolysis in Cerebral Infarction (TICI) 2b/3) was achieved in 36 (69%) patients. Favorable clinical outcome at 3 months, defined as a modified Rankin Scale score of 0-2, was achieved in 25 (48%) patients. Duration of intervention <30 min and its success, defined as TICI 2b/3 recanalization, were strong predictors of favorable clinical outcome at 90 days (p<0.001 and p<0.0001, respectively). Conclusions Our study indicates that endovascular treatment of WUS with stent retrievers and aspiration thrombectomy is safe and effective. [ABSTRACT FROM AUTHOR]

Background Artificial stroke models can be used for testing various thrombectomy devices. Objective To determine the value of combined stentriever-aspiration thrombectomy compared with the stentriever-alone approach. Methods We designed an in vitro model of the intracranial circulation with a focus on the middle cerebral artery (MCA) that closely resembles the human intracranial circulation. After introducing fresh clot in the MCA, we used conventional biplane angiography and microangiographic fluoroscopy to compare recanalization rates and occurrence of emboli in new, unaffected territory for thrombectomy approaches in which a stentriever (Solitaire flow restoration stentriever, Covidien) was used alone or in combination with continuous manual aspiration through a Navien catheter (Covidien). Results In a total of 22 experiments (11 for each approach), successful clot delivery to the MCA was achieved in all cases. Successful angiographic recanalization (thrombolysis in cerebral infarction score of 2b--3) was achieved more frequently with the combined stentriever-aspiration approach than with the stentriever-alone approach (in 10 vs 4 experiments, p=0.023). Emboli in new territory occurred in three experiments with the stentriever-alone approach, and none were seen with the combined approach (p=0.21). Conclusions The combined stentriever-aspiration approach to thrombectomy leads to better angiographic recanalization rates than use of the stentriever alone. Further experiments are needed to test the value of balloon-guide catheters and aspiration performed using other types of catheters and modes of aspiration. [ABSTRACT FROM AUTHOR]

Background Thrombus characteristics, including Hounsfield unit (HU) value to measure density and thrombus volume and length, can predict successful recanalization following IV thrombolysis with recombinant tissue plasminogen activator. Conflicting and limited data exist regarding the value of assessing thrombus properties in acute stroke cases treated with endovascular IA approaches. Methods We retrospectively reviewed cases of anterior circulation acute ischemic stroke in which a Solitaire stent retriever (ev3-Covidien) was the primary treatment device. We measured the following thrombus characteristics: absolute and corrected HU values; thrombus length and volume; clot burden score; and vessel bifurcation involvement. Fisher's exact test and the t test were used to study the association between these clot characteristics and successful recanalization (Thrombolysis in Cerebral Infarction (TICI) score 2b-3). Results We identified 41 patients with anterior circulation stroke treated with the Solitaire stent retriever as the primary treatment device. Successful recanalization (TICI score 2b-3) was achieved in 59% of cases. Higher absolute and corrected HU values were strongly predictive of successful recanalization (49.9±7.6 vs 43.8±6.6, p=0.01 for absolute HU values and 1.2±0.2 vs 1.0±0.1, p=0.03 for HU ratio in TICI 2b-3 and TICI 0-2a groups, respectively). There was no significant difference between recanalization and nonrecanalization groups in the other thrombus characteristics studied. Conclusions In acute stroke treated with Solitaire stent retriever thrombectomy, higher thrombus HU values are predictive of successful recanalization. Such information can be used in decision making when estimating recanalization success rate with different endovascular treatment approaches. [ABSTRACT FROM AUTHOR]

Objective Flexible large lumen aspiration catheters and stent retrievers have recently become available in the USA for the revascularization of large vessel occlusions presenting within the context of acute ischemic stroke (AIS). We describe a multicenter experience using a combined aspiration and stent retrieval technique for thrombectomy. Design A retrospective analysis to identify patients receiving combined manual aspiration and stent retrieval for treatment of AIS between August 2012 and April 2013 at six high volume stroke centers was conducted. Outcome variables, including recanalization rate, posttreatment National Institutes of Health Stroke Scale (NIHSS) score, symptomatic intracranial hemorrhage, discharge 90 day modified Rankin Scale (mRS) score, and mortality were evaluated. Results 105 patients were found that met the inclusion criteria for this retrospective study. Successful recanalization (Thrombolysis in Cerebral Infarction score 2B) was achieved in 92 (88%) of these patients. 44% of patients had favorable (mRS score 0-2) outcomes at 90 days. There were five (4.8%) symptomatic intracerebral hemorrhages and three procedure related deaths (2.9%). Conclusions Mechanical thrombectomy utilizing combined manual aspiration with a stent retriever is an effective and safe strategy for endovascular recanalization of large vessel occlusions presenting within the context of AIS. [ABSTRACT FROM AUTHOR]

In the SWIFT and TREVO 2 trials, aspiration thrombectomy was not able to be performed. Outside these studies, in post-market application, the interventionist can use aspiration thrombectomy in addition to stent device thrombectomy. This technique is described in detail in the present report. Combined aspiration/stentriever thrombectomy may improve recanalization efforts, simplify a second thrombectomy attempt if necessary and may limit distal embolization. [ABSTRACT FROM AUTHOR]

Background The development of new revascularization devices has improved recanalization rates and time, but not clinical outcomes. We report a prospectively collected clinical experience with a new technique utilizing a direct aspiration first pass technique with large bore aspiration catheter as the primary method for vessel recanalization. Methods 98 prospectively identified acute ischemic stroke patients with 100 occluded large cerebral vessels at six institutions were included in the study. The ADAPT technique was utilized in all patients. Procedural and clinical data were captured for analysis. Results The aspiration component of the ADAPT technique alone was successful in achieving Thrombolysis in Cerebral Infarction (TICI) 2b or 3 revascularization in 78% of cases. The additional use of stent retrievers improved the TICI 2b/3 revascularization rate to 95%. The average time from groin puncture to at least TICI 2b recanalization was 37 min. A 5MAX demonstrated similar success to a 5MAX ACE in achieving TICI 2b/3 revascularization alone (75% vs 82%, p=0.43). Patients presented with an admitting median National Institutes of Health Stroke Scale (NIHSS) score of 17.0 (12.0–21.0) and improved to a median NIHSS score at discharge of 7.3 (1.0–11.0). Ninety day functional outcomes were 40% (modified Rankin Scale (mRS) 0–2) and 20% (mRS 6). There were two procedural complications and no symptomatic intracerebral hemorrhages. Discussion The ADAPT technique is a fast, safe, simple, and effective method that has facilitated our approach to acute ischemic stroke thrombectomy by utilizing the latest generation of large bore aspiration catheters to achieve previously unparalleled angiographic outcomes. [ABSTRACT FROM AUTHOR]

Background The development of new revascularization devices has improved recanalization rates and time but not clinical outcomes. We report our initial results with a new technique utilizing a direct aspiration first pass technique with a large bore aspiration catheter as the primary method for vessel recanalization. Methods A retrospective evaluation of a prospectively captured database of 37 patients at six institutions was performed on patients where the ADAPT technique was utilized. The data represent the initial experience with this technique. Results The ADAPT technique alone was successful in 28 of 37 (75%) cases although six cases had large downstream emboli that required additional aspiration. Nine cases required the additional use of a stent retriever and one case required the addition of a Penumbra aspiration separator to achieve recanalization. The average time from groin puncture to at least Thrombolysis in Cerebral Ischemia (TICI) 2b recanalization was 28.1 min, and all cases were successfully revascularized. TICI 3 recanalization was achieved 65% of the time. On average, patients presented with an admitting National Institutes of Health Stroke Scale (NIHSS) score of 16.3 and improved to an NIHSS score of 4.2 by the time of hospital discharge. There was one procedural complication. Discussion This initial experience highlights the fact that the importance of the technique with which new stroke thrombectomy devices are used may be as crucial as the device itself. The ADAPT technique is a simple and effective approach to acute ischemic stroke thrombectomy. Utilizing the latest generation of large bore aspiration catheters in this fashion has allowed us to achieve excellent clinical and angiographic outcomes. [ABSTRACT FROM AUTHOR]

In the SWIFT and TREVO 2 trials, aspiration thrombectomy was not able to be performed. Outside these studies, in post-market application, the interventionist can use aspiration thrombectomy in addition to stent device thrombectomy. This technique is described in detail in the present report. Combined aspiration/stentriever thrombectomy may improve recanalization efforts, simplify a second thrombectomy attempt if necessary and may limit distal embolization. [ABSTRACT FROM AUTHOR]