Assessment of the safety and efficacy of the Zoom 45 and 55 reperfusion catheters for medium and distal mechanical thrombectomies: A multi-institutional study.

INTRODUCTION: The Zoom aspiration catheters harbor novel dimensions and construction to enhance trackability and deliverability. In addition, a beveled tip may improve thrombus interaction and aspiration force for a set inner diameter. This study evaluates their utility in medium and distal vessel occlusions. OBJECTIVE: To evaluate the safety and efficacy of Zoom 45 and 55 aspiration catheters in medium and distal vessel thrombectomy. METHODS: Patients treated for distal vessel occlusions via mechanical thrombectomy utilizing either the Zoom 45/55 catheter or a historical control catheter between 2021-2022 at two institutions were included in this study. Medium and distal occlusions were defined as any anterior or posterior cerebral artery branch as well as the M2-4 segment of the middle cerebral artery (MCA). Preprocedural, procedural, and postprocedural variables were obtained. RESULTS: Thirty-eight patients underwent thrombectomy with Zoom 45 or 55 catheters; four had multiple occluded vessels. Occlusion location included the M2 in 32 cases, M3-4 in 7 cases, A2 in 2 cases and P2 in 1 case. The mean number of passes per occlusion was 1.6 and overall successful reperfusion (TICI 2b or greater) was achieved in 84 % of cases. There were no symptomatic procedure-related complications such as perforation or post-procedural symptomatic ICH. Modified Rankin scores rates of 0-2, 3-5, and 6 at three months post-procedure were 35.7 %, 21.4 %, and 42.9 %, respectively. CONCLUSIONS: The Zoom beveled tip aspiration catheters are safe and effective for more challenging medium and distal vessel occlusions.

Racial and gender disparities in the management of acute pulmonary embolism.

OBJECTIVE: The aim of this study was to assess race and sex disparities in use and outcomes of various interventions in patient with acute pulmonary embolism (PE). METHODS: We included 129,445 patients with acute PE from the NIS from January 2016 to December 2019. Rates of inferior vena cava (IVC) filter placement, catheter-directed thrombolysis (CDT), CDT with ultrasound, systemic thrombolysis, surgical embolectomy, percutaneous thrombectomy, extracorporeal membrane oxygenation, and mechanical ventilation were compared between race and sex subgroups, along with length of hospital stay, major bleeding events, mortality, and other adverse events. Multivariate linear regression analysis was used to adjust for variables that were significantly different between race and sex, including demographic factors, comorbidities, socioeconomic factors, and hospital characteristics. RESULTS: Compared with White male patients, all subgroups had significantly higher odds of in-hospital mortality highest in Hispanic male patients (odds ratio [OR], 1.34; 95% confidence interval [CI], 1.090-1.640; P < .01). All subgroups also had a higher odds of major bleeding events and increased length of stay. All subgroups also had lower odds of receiving CDT, lowest in Black female patients (OR, 0.740; 95% CI, 0.660-0.820; P < .001) and Hispanic female patients (0.780; 95% CI, 0.650-0.940; P < .001) compared with White male patients. There was no significant difference in the use of systemic thrombolysis among subgroups. CONCLUSIONS: Black and Hispanic patients and female patients are less likely to undergo CDT compared with White male patients, in addition to having higher odds of mortality, major bleeding, and increased length of stay after management of PE. Further efforts are needed to mitigate disparate outcomes of PE management at not only an institutional, but at a national, level to promote health care equality.

Cost Effectiveness of Early Endovenous Thrombus Removal for Acute Iliofemoral Deep Vein Thrombosis in the United Kingdom.

OBJECTIVE: Early clot removal using endovascular intervention aims to reduce post-thrombotic syndrome (PTS) following iliofemoral deep venous thrombosis (DVT). This may reduce long term morbidity but incurs a higher initial cost. This study examined the cost effectiveness of catheter directed thrombolysis (CDT) and pharmacochemical thrombectomy (PMT) compared with oral anticoagulation (OAC) alone for treatment of acute iliofemoral DVT in the United Kingdom. METHODS: A combined decision tree (acute DVT complications) and Markov model (long term complications [PTS]) was used for decision analytic modelling with five states: no PTS, mild PTS, moderate PTS, severe PTS, and dead. All patients started with acute DVT. Patients who survived acute complications transitioned into the Markov model. Cycle time was six months. A healthcare payer perspective and lifetime horizon was used, adjusting for excess mortality due to history of thrombosis. Data for probabilities, transition probabilities, mortality, and utilities were obtained from the published literature. Cost data were obtained from UK NHS tariffs and published literature. Outcomes were mean lifetime cost, quality adjusted life years (QALYs), and cost effectiveness. RESULTS: Over a patient's lifetime, OAC was more costly (£37 206) than CDT (£32 043) and PMT (£36 288). Mean lifetime QALYs for OAC (12.9) were lower than CDT (13.5) and PMT (13.3). Therefore, in the incremental cost effectiveness analysis, both CDT and PMT were dominant: CDT was less costly (-£5 163) and more effective (+0.6 QALYs) than OAC, and PMT was also less costly (-£917) and more effective (+0.3 QALYs) than OAC. Results were robust to univariable sensitivity analyses, but probabilistic sensitivity analyses suggested considerable parameter uncertainty. CONCLUSION: Early interventional treatment of iliofemoral DVT is cost effective in the UK. Future clinical and epidemiological studies are needed to characterise parameter uncertainty. Further analysis of modern practice, alternative treatments, and optimised care models is warranted.

Machine learning prediction of hospital discharge disposition for inpatients with acute ischemic stroke following mechanical thrombectomy in the United States.

BACKGROUND AND PURPOSE: Predicting patient recovery and discharge disposition following mechanical thrombectomy remains a challenge in patients with ischemic stroke. Machine learning offers a promising prognostication approach assisting in personalized post-thrombectomy care plans and resource allocation. As a large national database, National Inpatient Sample (NIS), contain valuable insights amenable to data-mining. The study aimed to develop and evaluate ML models predicting hospital discharge disposition with a focus on demographic, socioeconomic and hospital characteristics. MATERIALS AND METHODS: The NIS dataset (2006-2019) was used, including 4956 patients diagnosed with ischemic stroke who underwent thrombectomy. Demographics, hospital characteristics, and Elixhauser comorbidity indices were recorded. Feature extraction, processing, and selection were performed using Python, with Maximum Relevance - Minimum Redundancy (MRMR) applied for dimensionality reduction. ML models were developed and benchmarked prior to interpretation of the best model using Shapley Additive exPlanations (SHAP). RESULTS: The multilayer perceptron model outperformed others and achieved an AUROC of 0.81, accuracy of 77 %, F1-score of 0.48, precision of 0.64, and recall of 0.54. SHAP analysis identified the most important features for predicting discharge disposition as dysphagia and dysarthria, NIHSS, age, primary payer (Medicare), cerebral edema, fluid and electrolyte disorders, complicated hypertension, primary payer (private insurance), intracranial hemorrhage, and thrombectomy alone. CONCLUSION: Machine learning modeling of NIS database shows potential in predicting hospital discharge disposition for inpatients with acute ischemic stroke following mechanical thrombectomy in the NIS database. Insights gained from SHAP interpretation can inform targeted interventions and care plans, ultimately enhancing patient outcomes and resource allocation.

Mechanical Thrombectomy with Intravenous Thrombolysis versus Thrombolysis Alone for the Treatment of Stroke: A Systematic Review of Economic Evaluations.

Mechanical thrombectomy has revolutionized the management of stroke by improving the recanalization rates and reducing deleterious consequences. It is now the standard of care despite the high financial cost. A considerable number of studies have evaluated its cost effectiveness. Therefore, this study aimed to identify economic evaluations of mechanical thrombectomy with thrombolysis compared with thrombolysis alone to provide an update of existing evidence, focusing on the period after proof of effectiveness of mechanical thrombectomy. Twenty-one studies were included in the review: 18 were model-based economic evaluations to simulate long-term outcomes and costs, and 19 were conducted in high-income countries. Incremental cost-effectiveness ratios ranged from -$5,670 to $74,216 per quality-adjusted life year. Mechanical thrombectomy is cost-effective in high-income countries and in the populations selected for clinical trials. However, most of the studies used the same data. There is a lack of real-world and long-term data to analyze the cost effectiveness of mechanical thrombectomy in treating the global burden of stroke.

Shorter Door-to-Needle Times Are Associated With Better Outcomes After Intravenous Thrombolytic Therapy and Endovascular Thrombectomy for Acute Ischemic Stroke.

BACKGROUND: Existing data and clinical trials could not determine whether faster intravenous thrombolytic therapy (IVT) translates into better long-term functional outcomes after acute ischemic stroke among those treated with endovascular thrombectomy (EVT). Patient-level national data can provide the required large population to study the associations between earlier IVT, versus later, with longitudinal functional outcomes and mortality in patients receiving IVT+EVT combined treatment. METHODS: This cohort study included older US patients (age ≥65 years) who received IVT within 4.5 hours or EVT within 7 hours after acute ischemic stroke using the linked 2015 to 2018 Get With The Guidelines-Stroke and Medicare database (38 913 treated with IVT only and 3946 with IVT+EVT). Primary outcome was home time, a patient-prioritized functional outcome. Secondary outcomes included all-cause mortality in 1 year. Multivariate logistic regression and Cox proportional hazards models were used to evaluate the associations between door-to-needle (DTN) times and outcomes. RESULTS: Among patients treated with IVT+EVT, after adjusting for patient and hospital factors, including onset-to-EVT times, each 15-minute increase in DTN times for IVT was associated with significantly higher odds of zero home time in a year (never discharged to home) (adjusted odds ratio, 1.12 [95% CI, 1.06-1.19]), less home time among those discharged to home (adjusted odds ratio, 0.93 per 1% of 365 days [95% CI, 0.89-0.98]), and higher all-cause mortality (adjusted hazard ratio, 1.07 [95% CI, 1.02-1.11]). These associations were also statistically significant among patients treated with IVT but at a modest degree (adjusted odds ratio, 1.04 for zero home time, 0.96 per 1% home time for those discharged to home, and adjusted hazard ratio 1.03 for mortality). In the secondary analysis where the IVT+EVT group was compared with 3704 patients treated with EVT only, shorter DTN times (≤60, 45, and 30 minutes) achieved incrementally more home time in a year, and more modified Rankin Scale 0 to 2 at discharge (22.3%, 23.4%, and 25.0%, respectively) versus EVT only (16.4%, P<0.001 for each). The benefit dissipated with DTN>60 minutes. CONCLUSIONS: Among older patients with stroke treated with either IVT only or IVT+EVT, shorter DTN times are associated with better long-term functional outcomes and lower mortality. These findings support further efforts to accelerate thrombolytic administration in all eligible patients, including EVT candidates.

Prognostic importance of nutritional assessment in patients with acute ischemic stroke undergoing endovascular thrombectomy.

OBJECTIVE: The prevalence of malnutrition in patients with acute ischemic stroke (AIS) can range from 8% to 34%. It has been shown that prognostic nutritional index (PNI) and control nutritional status (CONUT) scores can provide an opportunity to make prognostic predictions in some disease groups. Previous studies have shown a close relationship between malnutrition scores and stroke prognosis. We evaluated the effect of nutritional scores on in-hospital and long-term mortality in AIS patients undergoing endovascular therapy (EVT). PATIENTS AND METHODS: 219 patients who underwent EVT for the AIS were included in this retrospective design and cross-sectional study. The primary endpoint of the study was accepted as all-cause death including in-hospital death, 1-year death, and 3-years death. RESULTS: A total of 57 patients died in the hospital. In-hospital mortality rate was higher in the high CONUT group [36 (49.3%), 10 (13.7%), 11 (15.1%), p<0.001]. A total of 78 patients died within one year, and 1-year mortality was higher in the high CONUT group [43 (58.9%), 21 (28.8), 14 (19.2), p<0.001]. At the end of the 3-year follow-up, 90 patients had died, and the 3-year mortality rate was significantly higher in groups with a high CONUT score than in those with a low CONUT score (p<0.001). CONCLUSIONS: A higher CONUT score, calculated easily by simple scoring with parameters studied from peripheral blood before the EVT procedure, is an independent predictor of in-hospital, 1-year, and 3-years all-cause mortality.

Patterns in the number of interventionalists for endovascular treatment of acute ischemic stroke in the US.

BACKGROUND: Endovascular thrombectomy (ET) has become the standard of stroke care for large vessel occlusion acute ischemic stroke (AIS) involving the anterior circulation. With continued eligibility expansion, the demand for neuro-intervention is growing. Current estimates indicate inadequate supply of interventionalists. However, there is limited data describing the number of interventionalists per hospital in the US, and correlations with outcomes. METHODS: We used Medicare 100% sample datasets and included all AIS admissions from 2018 to 2019, using validated International Classification of Diseases, 10th Revision, Clinical Modification codes to identify AIS and comorbidities. We utilized National Provider Identifier codes to identify distinct interventionalists at the hospital. We examined outcomes at the hospital level, including percent of AIS treated with thrombolysis, percent of AIS with inpatient mortality, percent of AIS with discharge home, and percent of AIS with death within 30 days. RESULTS: Among 471,427 AIS admissions, 16,253 received ET over the 2-year period of the study. Only 683 of 4576 AIS-treating institutions provided ET (14.9%). These ET centers most frequently only had one interventionalist performing ET and were clustered in large metropolitan areas with high AIS volumes. As AIS volumes, ET volumes, and mean NIHSS scores increased, so did the number of interventionalists. With each additional interventionalist, there was an increased likelihood of poor outcomes including inpatient mortality, discharge home, and 30-day mortality. CONCLUSIONS: We confirmed a relative lack of neuro-interventionalists among US hospitals, with a concentration of interventionalists in urban, high-volume centers. The greater likelihood of poor outcomes associated with increasing number of interventionalists is likely due to increasing complexity and severity of cases at high-volume ET centers, but further study is needed.

Investigating the "Weekend Effect" on Outcomes of Patients Undergoing Endovascular Mechanical Thrombectomy for Ischemic Stroke.

OBJECTIVES: With growing evidence of its efficacy for patients with large-vessel occlusion (LVO) ischemic stroke, the use of endovascular thrombectomy (EVT) has increased. The "weekend effect," whereby patients presenting during weekends/off hours have worse clinical outcomes than those presenting during normal working hours, is a critical area of study in acute ischemic stroke (AIS). Our objective was to evaluate whether a "weekend effect" exists in patients undergoing EVT. METHODS: This retrospective, cross-sectional analysis of the 2016-2018 Nationwide Inpatient Sample data included patients ≥18 years with documented diagnosis of ischemic stroke (ICD-10 codes I63, I64, and H34.1), procedural code for EVT, and National Institutes of Health Stroke Scale (NIHSS) score; the exposure variable was weekend vs. weekday treatment. The primary outcome was in-hospital death; secondary outcomes were favorable discharge, extended hospital stay (LOS), and cost. Logistic regression models were constructed to determine predictors for outcomes. RESULTS: We identified 6052 AIS patients who received EVT (mean age 68.7±14.8 years; 50.8% female; 70.8% White; median (IQR) admission NIHSS 16 (10-21). The primary outcome of in-hospital death occurred in 560 (11.1%); the secondary outcome of favorable discharge occurred in 1039 (20.6%). The mean LOS was 7.8±8.6 days. There were no significant differences in the outcomes or cost based on admission timing. In the mixed-effects models, we found no effect of weekend vs. weekday admission on in-hospital death, favorable discharge, or extended LOS. CONCLUSION: These results demonstrate that the "weekend effect" does not impact outcomes or cost for patients who undergo EVT for LVO.

Rapid Assessment of Blood Pressure Variability and Outcome After Successful Thrombectomy.

BACKGROUND AND PURPOSE: High blood pressure (BP) variability after endovascular stroke therapy is associated with poor outcome. Conventional BP variability measures require long recordings, limiting their utility as a risk assessment tool to guide clinical decision-making. Here, we performed rapid assessment of BP variability by spectral analysis and evaluated its association with early clinical improvement and long-term functional outcomes. METHODS: We conducted a prospective study of 146 patients with anterior circulation ischemic stroke who underwent successful endovascular stroke therapy. Spectral analysis of 5-minute recordings of beat-to-beat BP was used to quantify BP variability. Outcomes included initial clinical response and modified Rankin Scale at 90 days. RESULTS: Increased BP variability at high frequencies was independently associated with poor functional outcome at 90 days (adjusted odds ratio [aOR], 1.85 [95% CI, 1.07-3.25], P=0.03; low-/high-frequency ratio aOR, 0.67 [95% CI, 0.46-0.92], P=0.02) and reduced likelihood of an early neurological recovery (aOR, 0.62 [95% CI, 0.44-0.91], P=0.01 and aOR, 1.37 [95% CI, 1.03-1.87], P=0.04, respectively). CONCLUSIONS: High-frequency BP oscillations after successful reperfusion may be harmful and associate with a decreased likelihood of neurological recovery and favorable functional outcomes. Rapid assessment of BP variability throughout the postreperfusion period is feasible and may allow for a more personalized BP management.

Correlations Between Physician and Hospital Stroke Thrombectomy Volumes and Outcomes: A Nationwide Analysis.

Background and Purpose: Despite the Joint Commission's certification requirement of ≥15 stroke thrombectomy (ST) cases per center and proceduralist annually, the relationship between ST case volumes and outcomes is uncertain. We sought to determine whether a proceduralist or hospital volume threshold exists that is associated with better outcomes among Medicare beneficiaries. Methods: Retrospective cohort study using validated International Classification of Diseases, Tenth Revision, Clinical Modification codes to identify admissions with acute ischemic stroke and treatment with ST. We used de-identified, national 100% inpatient Medicare data sets from January 1, 2016, to December 31, 2017 for US individuals aged ≥65 years. We calculated total procedures by proceduralist and hospital. We performed adjusted logistic regression of total cases as a predictor of inpatient mortality, good outcome (defined by dichotomized discharge disposition of inpatient rehabilitation or better), and 30-day readmission. We adjusted for sex, age, Charlson Comorbidity Index, availability of neurocritical care, teaching hospital status, socioeconomic status, 2-year stroke volume, and urban versus rural hospital location. We dichotomized case numbers incrementally to determine a volume threshold for better outcomes. Results: Thirteen thousand three hundred thirty-five patients were treated with ST by 2754 proceduralists at 641 hospitals. For every 10 more proceduralist cases, patients had 4% lower adjusted odds of inpatient mortality (adjusted odds ratio, 0.96 [95% CI, 0.95­0.98], P<0.0001) and 3% greater adjusted odds of good outcome (adjusted odds ratio, 1.03 [95% CI, 1.02­1.04], P<0.0001). For every 10 more hospital cases, patients had 2% lower odds of inpatient mortality (adjusted odds ratio, 0.98 [95% CI, 0.98­0.99], P=0.0003) and 2% greater odds of good outcome (adjusted odds ratio, 1.02 [95% CI, 1.01­1.02], P<0.0001). With increasing volumes, there were higher odds of better outcomes. Conclusions: Nationally, higher proceduralist and hospital ST case volumes were associated with reduced inpatient mortality and better outcome. These data support volume requirements in guidelines for ST training and certification.

Neighborhood Socioeconomic Status and Mechanical Thrombectomy Outcomes.

BACKGROUND/PURPOSE: Our study aimed to assess the impacts of neighborhood socioeconomic status on mechanical thrombectomy (MT) outcomes for acute ischemic stroke (AIS). METHODS: We conducted a prospective observational study of consecutive adult AIS patients treated with MT at one US comprehensive stroke center from 2012 to 2018. A composite neighborhood socioeconomic score (nSES) was created using patient home address, median household income, percentage of households with interest, dividend, or rental income, median value of housing units, percentage of persons 25 or older with high school degrees, college degrees or holding executive, managerial or professional specialty occupations. Using this score, patients were divided into low, middle and high nSES tertiles. Outcomes included 90-day functional independence, in-hospital mortality, length of hospital stay, discharge location, time to recanalization, successful recanalization, and symptomatic intracranial hemorrhage (sICH). RESULTS: 328 patients were included. Between the three nSES groups, proportion of White patients, time-to-recanalization and admission NIH stroke scale differed significantly (p<0.05). Patients in the high nSES tertile were more likely to be functionally dependent at 90 days (unadjusted OR, 95% CI, 1.91 [1.10, 3.36]) and were less likely to die in the hospital (unadjusted OR, 95% CI, 0.46, [0.20, 0.98]). Further, patients in the high nSES tertile had decreased times to recanalization (median time in minutes, low=335, mid=368, high=297, p=0.04). However, after adjusting for variance in race and severity of stroke, the differences in clinical outcomes were not significant. CONCLUSION: This study highlights how unadjusted neighborhood socioeconomic status is significantly associated with functional outcome, mortality, and time-to-recanalization following MT for AIS. Since adjustment modifies the significant association, the socioeconomic differences may be influenced by differences in pre-hospital factors that drive severity of stroke and time to recanalization. Better understanding of the interplay of these factors may lead to timelier evaluation and improvement in patient outcomes.

Sex and racial disparity in utilization and outcomes of t-PA and thrombectomy in acute ischemic stroke.

BACKGROUND/PURPOSE: Racial/ethnic and sex disparity may occur in stroke throughout the continuum of care. Endovascular therapy (EVT) became standard of care in 2015 for eligible patients with acute ischemic stroke (AIS). We evaluated for racial and sex differences in t-PA and EVT utilization and outcomes in 2016 in the National Inpatient Sample. METHODS: Treatment rates for t-PA, EVT, and t-PA+EVT and outcomes including home discharge, in-hospital mortality and prolonged length of stay (pLOS) were evaluated by sex and race. Multivariate survey-logistic regression was performed to evaluate outcomes. RESULTS: The study had 468,630 patients - 49.3% men, 50.7% women; 69.3% whites, and 30.7% non-whites. There was no difference in treatment utilization by sex, women vs men for t-PA (7.65% vs 7.76%; aOR:1.02; 95% CI:0.97-1.07), EVT (1.74% vs 1.67%; aOR:1.09; 95% CI:0.99-1.20) and t-PA+EVT (0.57% vs 0.57%; aOR:1.01; 95% CI:0.85-1.21); and by race, non-white vs white for t-PA (7.62% vs 7.74%; aOR:0.98; 95% CI:0.93-1.05), EVT (1.62% vs 1.74%; aOR:0.91; 95% CI:0.78-1.07), and t-PA+EVT(0.59% vs 0.56%; aOR:1.05; 95% CI:0.84-1.30). Compared to men, women treated with t-PA had less home discharge (37.2% vs 46.3%; aOR:0.81; 95% CI:0.72-0.90), more in-hospital mortality (5.7% vs 3.9%; aOR:1.37; 95% CI:1.06-1.77) and less pLOS (8.3% vs 9.6%; aOR:0.82; 95% CI:0.69-0.98); women treated with EVT had less home discharge (15.8% vs 23.7%; aOR:0.69; 95% CI:0.52-0.91). Compared to whites, non-whites treated with t-PA had lower odds of home discharge (42.1% vs 41.6%; aOR:0.79; 95% CI:0.69-0.90), less in-hospital mortality (3.7% vs 5.3%; aOR:0.65; 95% CI:0.49-0.87), and higher pLOS (11.4% vs 7.9%; aOR:1.3; 95% CI:1.07-1.56); non-whites treated with EVT had less home discharge (18%vs 20.2%; aOR:0.70; 95% CI:0.51-0.97) and higher pLOS (35.1% vs 24%; aOR:1.52; 95% CI:1.16-1.99). CONCLUSION: Sex and racial disparity exists for outcomes of t-PA and EVT despite no difference in utilization rates.

Individual Choice for the Aspiration Thrombectomy Treatment of Acute Iliofemoral Deep Venous Thrombosis.

OBJECTIVE: To compare clinical efficacy, safety and cost of AngioJet rheolytic thrombectomy (ART) plus catheter-directed thrombolysis (CDT) and manual aspiration thrombectomy (MAT) plus CDT for acute iliofemoral deep venous thrombosis (DVT). METHODS: This was a retrospective study. A total of 126 DVT patients met the inclusion criteria. Sixty-one patients were included in the ART group and sixty-five in the MAT group. Clinical parameters were used to compare the groups. Clinical outcomes, complications and various medical expenses were analyzed. RESULTS: Technical success rates were 100% in ART and MAT group. There was no significant difference in the rate of thrombus clearance (lysis grades II and III) between ART group (98.36%) and MAT group (100%) (P = 0.311). The incidence of venous damage was slightly higher in the MAT group (4.6%) than in the ART group (0%) (P = 0.245). The cost of the ART group ($8,291.7 ± 471.4) was significantly higher than that of the MAT group ($4,632.5 ± 441.7) (P < 0.001). CONCLUSIONS: ART and MAT appear similar with good clinical outcomes for acute iliofemoral DVT. MAT substantially lowers mean cost per patient compared to ART.

Predictors of Successful First-Pass Thrombectomy with a Balloon Guide Catheter: Results of a Decision Tree Analysis.

Complete recanalization after a single retrieval maneuver is an interventional goal in acute ischemic stroke and an independent factor for good clinical outcome. Anatomical biomarkers for predicting clot removal difficulties have not been comprehensively analyzed and await unused. We retrospectively evaluated 200 consecutive patients who suffered acute stroke and occlusion of the anterior circulation and were treated with mechanical thrombectomy through a balloon guide catheter (BGC). The primary objective was to evaluate the influence of carotid tortuosity and BGC positioning on the one-pass Modified Thrombolysis in Cerebral Infarction Scale (mTICI) 3 rate, and secondarily, the influence of communicating arteries on the angiographic results. After the first-pass mTICI 3, recanalization fell from 51 to 13%. The regression models and decision tree (supervised machine learning) results concurred: carotid tortuosity was the main constraint on efficacy, reducing the likelihood of mTICI 3 after one pass to 30%. BGC positioning was relevant only in carotid arteries without elongation: BGCs located in the distal internal carotid artery (ICA) had a 70% probability of complete recanalization after one pass, dropping to 43% if located in the proximal ICA. These findings demonstrate that first-pass mTICI 3 is influenced by anatomical and interventional factors capable of being anticipated, enabling the BGC technique to be adapted to patient's anatomy to enhance effectivity.

Assessment of Collateral Circulation Using Perfusion CT in Middle Cerebral Artery Thrombectomy-Treated Patients.

INTRODUCTION: The prognostic value of leptomeningeal collateral circulation in thrombectomy-treated patients remains unclear. We evaluated the construct validity of assessing leptomeningeal collateral circulation using a new regional perfusion CT source image-based approach, the Perfusion Acquisition for THrombectomy Scale (PATHS). We also compared the prognostic value of PATHS with a further 6 scales based on various techniques: CT-angiography, perfusion CT, and digital subtraction angiography. Additionally, we studied the relationship between the scores for the different scales. PATIENTS AND METHODS: We performed a retrospective study of consecutive patients with stroke and M1/terminal carotid occlusion treated with thrombectomy in our center. Leptomeningeal collateral circulation was prospectively evaluated using 7 scales: Tan and Miteff (CT Angiography); Calleja, Cao, American Society of Intervention and Therapeutic Neuroradiology/Society of Interventional Radiology, and PATHS (perfusion); and Christoforidis (Digital Subtraction Angiography). Correlations were studied using the Spearman method. RESULTS: The study population comprised 108 patients. All scales predicted the modified Rankin Scale at 3 months (P ≤ .02) and all but 1 (Christoforidis) correlated with 24-hour brain infarct volume (P ≤ .02). These correlations were higher with PATHS (rho = -0.47, P < .001 for 3-month modified Rankin Scale; rho = -0.35, P < .001 for follow-up infarct volume). The multivariate analysis showed PATHS to be an independent predictor of modified Rankin Scale at 3 months less than equal to 2. A crosscorrelation analysis revealed a better correlation between scales that used the same techniques. CONCLUSIONS: PATHS can be used to assess leptomeningeal collateral circulation. PATHS had better prognostic value than other scales; therefore, it might be considered for assessment of leptomeningeal collateral circulation in candidates for thrombectomy. The moderate correlation between scales suggests that scores are not interchangeable.

Cost-effectiveness of stent-retriever thrombectomy in large vessel occlusion strokes of the anterior circulation: Analysis from the French societal perspective.

OBJECTIVES: To determine the cost-effectiveness of stent retriever thrombectomy (SRT) added to standard of care (SOC) in large vessel occlusion (LVO) strokes, adopting the French societal perspective given the lack of published studies with such perspective. METHODS: We developed an hybrid model (decision tree until one year post-stroke followed by a Markov model from one year onward). The time horizon was 20 years. We calculated transition probabilities across the modified Rankin Scale (mRS) based on a published meta-analysis. The main outcome measure was quality adjusted life-years (QALYs) gained. Resources and input costs were derived from a literature search. We calculated the incremental cost-effectiveness ratio (ICER) expressed as cost/QALY. We used 1-way deterministic and probabilistic sensitivity analysis (PSA) to evaluate the model uncertainty. RESULTS: In the base-case, adding SRT to SOC resulted in increased effectiveness of 0.73 QALY while total costs were reduced by 3,874€ (ICER of -5,400€/QALY). In the scenario analysis adopting the French healthcare system perspective, the ICER was 4,901€/QALY. Parameters the most influential were the relative risks of SRT over SOC for 90-days mortality and for 90-days mRS 0-2, and the time horizon. PSA showed the 95% confidence interval of the ICER was -21,324 to 4,591€/QALY, with SRT having 85.5% chance to be dominant and 100% to be cost-effective at a threshold of 50,000€/QALY. CONCLUSION: SRT was dominant from a French societal perspective, from 9 years post-stroke onwards. Cost-effectiveness of SRT added to SOC becomes undisputable with evidences from payer and societal viewpoints.

Case Fatality Decline from 2009 to 2013 among Medicare Beneficiaries with Ischemic Stroke.

OBJECTIVES: This study aimed to examine the temporal trend of 30-day and 1-year mortality among U.S. Medicare beneficiaries who were hospitalized for ischemic stroke, with special focus on the mortality among subgroup of patients in relation to acute reperfusion therapies including intravenous thrombolysis (IVT) and endovascular thrombectomy (EVT). METHODS: We evaluated Medicare fee-for-service beneficiaries age 65 years or older who were hospitalized for ischemic stroke between 2009 and 2013. Multivariable Cox proportional hazards models were generated to analyze the trend of adjusted mortality. RESULTS: A total of 1,070,574 patients were included in the study. The 30-day mortality did not change among patients who were not treated with IVT or EVT. It decreased by 13% among patients treated with IVT but not EVT (HR = .87, 95% CI .82-.92), 25% among patients treated with EVT but not IVT (HR = .75, 95% CI .59-.95), and 37% among patients treated with both IVT and EVT (HR = .63, 95% CI .52-.77). One-year mortality decreased by 19% among patients who were not treated with IVT nor EVT (HR = .81, 95% CI .80-.83), 22% among those treated with IVT but not EVT (HR = .78, 95% CI .75-.81), 33% among those treated with EVT but not IVT (HR = .67, 95% CI .55-.81), and 38% among those treated with both IVT and EVT (HR = .62, 95% CI .53-.73). CONCLUSIONS: From 2009 to 2013, the 30-day stroke case fatality decreased only among the patients received reperfusion therapy. The 1-year mortality declined among all the stroke patients, with the greatest decline among those treated with both IVT and EVT.

Feasibility of a circulation model for the assessment of endovascular recanalization procedures and periprocedural thromboembolism in-vitro.

Aim of this study was to establish a simple and highly reproducible physiological circulation model to investigate endovascular device performance. The developed circulation model included a pneumatically driven pulsatile pump to generate a flow rate of 2.7 L/min at 70 beats per minute. Sections from the superficial femoral arteries were used in order to simulate device/tissue interaction and a filter was integrated to analyze periinterventional thromboembolism of white, red and mixed thrombi. The working fluid (3 L) was a crystalloid solution constantly tempered at 36.5 °C. To evaluate the model, aspiration thrombectomy, stent-implantation and thrombectomy with the Fogarty catheter were performed. Usability of the model was measured by the System Usability Scale (SUS) - Score. Histological specimens were prepared and analyzed postinterventional to quantify tissue/device interaction. Moreover, micro- and macroembolism were evaluated for each thrombus entity and each device. Results were tested for normality using the D'Agostino-Pearson test. Statistical comparisons of two groups were performed using the Student's t-test. All devices were able to remove the occlusions after a maximum of 2 attempts. First-pass-recanalization was not fully achieved for aspiration thrombectomy of mixed thrombi (90.6%), aspiration thrombectomy of red thrombi (84.4%) and stent-implantation in occlusions of red thrombi (92.2%). Most micro- and macroembolism were observed using the Fogarty catheter and after stent-implantation in occlusions of white thrombi. Histological examinations revealed a significant reduction of the vascular layers suggesting vascular damage after use of the Fogarty catheter (327.3 ± 3.5 µm vs. 440.6 ± 3.9 µm; p = 0.026). Analysis of SUS rendered a mean SUS-Score of 80.4 which corresponds to an excellent user acceptability of the model. In conclusion, we describe a stable, easy to handle and reproducible physiological circulation model for the simulation of endovascular thrombectomy including device performance and thromboembolism.

Dual energy CT after stroke thrombectomy alters assessment of hemorrhagic complications.

OBJECTIVE: To determine whether dual energy CT with a combined approach (cDECT) using a plain noncontrast monochromatic CT (pCT), a water-weighted image after iodine removal, and an iodine-weighted image changes the diagnosis and classification of intracranial hemorrhage (ICH) after endovascular thrombectomy (EVT) in acute ischemic stroke compared to a pCT image alone without separate water and iodine weighting. METHOD: During 2012 to 2016, 372 patients at our comprehensive stroke center underwent DECT scans within 36 hours after EVT. Two readers evaluated pCT compared to a second reading with cDECT, establishing the diagnosis of ICH and grading it per the Heidelberg and Safe Implementation of Thrombolysis in Stroke-Monitoring Study (SITS-MOST) classifications. RESULT: Using cDECT changed the ICH diagnosis to contrast staining only in 34% (52 of 152), modified the ICH grade in 10% (15 of 152), and diagnosed initially undetected ICH in 2% (5 of 220). pCT alone had 95% sensitivity, 80% specificity, 66% positive predictive value, 98% negative predictive value, and 85% accuracy for ICH compared to cDECT. Interreader agreement on the presence of ICH increased with cDECT compared to pCT (Cohen κ = 0.77 [95% confidence interval 0.69-0.84] vs 0.68 [0.61-0.76]). CONCLUSION: cDECT within 36 hours after EVT changes the radiologic report regarding posttreatment ICH in a considerable proportion of patients undergoing EVT compared to pCT alone. This could affect decision-making regarding monitoring, secondary prevention, and prognostication. The cDECT scan could improve the interpretation consistency of high-attenuating changes on post-EVT images.