Access to Mechanical Thrombectomy for Ischemic Stroke in the United States

Modeling Robotic-Assisted Mechanical Thrombectomy Procedures with the CorPath GRX Robot: The Core-Flow Study

BACKGROUND AND PURPOSE

Endovascular robotic devices may enable experienced neurointerventionalists to remotely perform endovascular thrombectomy. This study aimed to assess the feasibility, safety, and efficacy of robot-assisted endovascular thrombectomy compared with manual procedures by operators with varying levels of experience, using a 3D printed neurovascular model.

MATERIALS AND METHODS

M1 MCA occlusions were simulated in a 3D printed neurovascular model, linked to a CorPath GRX robot in a biplane angiography suite. Four interventionalists performed manual endovascular thrombectomy (n = 45) and robot-assisted endovascular thrombectomy (n = 37) procedures. The outcomes included first-pass recanalization (TICI 2c-3), the number and size of generated distal emboli, and procedural length.

RESULTS

A total of 82 experimental endovascular thrombectomies were conducted. A nonsignificant trend favoring the robot-assisted endovascular thrombectomy was observed in terms of final recanalization (89.2% versus manual endovascular thrombectomy, 71.1%; P = .083). There were no differences in total mean emboli count (16.54 [SD, 15.15] versus 15.16 [SD, 16.43]; P = .303). However, a higher mean count of emboli of > 1 mm was observed in the robot-assisted endovascular thrombectomy group (1.08 [SD, 1.00] versus 0.49 [SD, 0.84]; P = .001) compared with manual endovascular thrombectomy. The mean procedural length was longer in robot-assisted endovascular thrombectomy (6.43 [SD, 1.71] minutes versus 3.98 [SD, 1.84] minutes; P < .001). Among established neurointerventionalists, previous experience with robotic procedures did not influence recanalization (95.8% were considered experienced; 76.9% were considered novices; P = .225).

CONCLUSIONS

In a 3D printed neurovascular model, robot-assisted endovascular thrombectomy has the potential to achieve recanalization rates comparable with those of manual endovascular thrombectomy within competitive procedural times. Optimization of the procedural setup is still required before implementation in clinical practice.

Becoming a thrombectomy-capable stroke center: Clinical and medico-economical effectiveness at the hospital level

INTRODUCTION

Too few patients benefit from endovascular therapy (EVT) in large vessel occlusion acute stroke (LVOS), and various acute stroke care paradigms are currently investigated to reduce these inequalities in health access. We aimed to investigate whether newly set-up thrombectomy-capable stroke centers (TSC) offered a safe, effective and cost-effective procedure.

PATIENTS AND METHODS

This French retrospective study compared the outcomes of LVOS patients with an indication for EVT and treated at the Perpignan hospital before on-site thrombectomy was available (Primary stroke center), and after formation of local radiology team for neurointervention (TSC). Primary endpoints were 3-months functional outcomes, assessed by the modified Rankin scale. Various safety endpoints for ischemic and hemorragic procedural complications were assessed. We conducted a medico-economic analysis to estimate the cost-benefit of becoming a TSC for the hospital.

RESULTS

The differences between 422 patients in the PSC and 266 in the TSC were adjusted by the means of weighted logistic regression. Patients treated in the TSC had higher odds of excellent functional outcome (aOR 1.77 [1.16-2.72], p = 0.008), with no significant differences in the rates of procedural complications. The TSC setting shortened onset-to-reperfusion times by 144 min (95% CI [131-155]; p < 0.0001), and was cost-effective after 21 treated LVOS patients. On-site thrombectomy saves 10.825€ per patient for the hospital.

DISCUSSION

Our results demonstrate that the TSC setting improves functional outcomes and reduces intra-hospital costs in LVOS patients. TSCs could play a major public health role in acute stroke care and access to EVT.

Artificial intelligence to enhance prehospital stroke diagnosis and triage: a perspective

As health systems organize to deliver the highest quality stroke care to their patients, there is increasing emphasis being placed on prehospital stroke recognition, accurate diagnosis, and efficient triage to improve outcomes after stroke. Emergency medical services (EMS) personnel currently rely heavily on dispatch accuracy, stroke screening tools, bypass protocols and prehospital notification to care for patients with suspected stroke, but novel tools including mobile stroke units and telemedicine-enabled ambulances are already changing the landscape of prehospital stroke care. Herein, the authors provide our perspective on the current state of prehospital stroke diagnosis and triage including several of these emerging trends. Then, we provide commentary to highlight potential artificial intelligence (AI) applications to improve stroke detection, improve accurate and timely dispatch, enhance EMS training and performance, and develop novel stroke diagnostic tools for prehospital use.

Validation of the Passive Surveillance Stroke Severity Score in Three Canadian Provinces

BACKGROUND

Stroke outcomes research requires risk-adjustment for stroke severity, but this measure is often unavailable. The Passive Surveillance Stroke SeVerity (PaSSV) score is an administrative data-based stroke severity measure that was developed in Ontario, Canada. We assessed the geographical and temporal external validity of PaSSV in British Columbia (BC), Nova Scotia (NS) and Ontario, Canada.

METHODS

We used linked administrative data in each province to identify adult patients with ischemic stroke or intracerebral hemorrhage between 2014-2019 and calculated their PaSSV score. We used Cox proportional hazards models to evaluate the association between the PaSSV score and the hazard of death over 30 days and the cause-specific hazard of admission to long-term care over 365 days. We assessed the models' discriminative values using Uno's c-statistic, comparing models with versus without PaSSV.

RESULTS

We included 86,142 patients (n = 18,387 in BC, n = 65,082 in Ontario, n = 2,673 in NS). The mean and median PaSSV were similar across provinces. A higher PaSSV score, representing lower stroke severity, was associated with a lower hazard of death (hazard ratio and 95% confidence intervals 0.70 [0.68, 0.71] in BC, 0.69 [0.68, 0.69] in Ontario, 0.72 [0.68, 0.75] in NS) and admission to long-term care (0.77 [0.76, 0.79] in BC, 0.84 [0.83, 0.85] in Ontario, 0.86 [0.79, 0.93] in NS). Including PaSSV in the multivariable models increased the c-statistics compared to models without this variable.

CONCLUSION

PaSSV has geographical and temporal validity, making it useful for risk-adjustment in stroke outcomes research, including in multi-jurisdiction analyses.

Variation in US acute ischemic stroke treatment by hospital regions: limited endovascular access despite evidence

BACKGROUND

Although national organizations recognize the importance of regionalized acute ischemic stroke (AIS) care, data informing expansion are sparse. We assessed real-world regional variation in emergent AIS treatment, including growth in revascularization therapies and stroke center certification. We hypothesized that we would observe overall growth in revascularization therapy utilization, but observed differences would vary greatly regionally.

METHODS

A retrospective cross-sectional analysis was carried out of de-identified national inpatient Medicare Fee-for-Service datasets from 2016 to 2019. We identified AIS admissions and treatment with thrombolysis and endovascular thrombectomy (ET) with International Classification of Diseases, 10th Revision, Clinical Modification codes. We grouped hospitals in Dartmouth Atlas of Healthcare Hospital Referral Regions (HRR) and calculated hospital, demographic, and acute stroke treatment characteristics for each HRR. We calculated the percent of hospitals with stroke certification and AIS cases treated with thrombolysis or ET per HRR.

RESULTS

There were 957 958 AIS admissions. Relative mean (SD) growth in percent of AIS admissions receiving revascularization therapy per HRR from 2016 to 2019 was 13.4 (31.7)% (IQR -6.1-31.7%) for thrombolysis and 28.0 (72.0)% (IQR 0-56.0%) for ET. The proportion of HRRs with decreased or no difference in ET utilization was 38.9% and the proportion of HRRs with decreased or no difference in thrombolysis utilization was 32.7%. Mean (SD) stroke center certification proportion across HRRs was 45.3 (31.5)% and this varied widely (IQR 18.3-73.4%).

CONCLUSIONS

Overall growth in AIS treatment has been modest and, within HRRs, growth in AIS treatment and the proportion of centers with stroke certification varies dramatically.

The evolution of acute stroke care in Germany from 2019 to 2021: analysis of nation-wide administrative datasets

BACKGROUND

The treatment of ischemic stroke (IS) has changed considerably in recent years. Particularly the advent of mechanical thrombectomy (MTE) has revolutionized the available treatment options. Most patients in developed countries have access to intravenous thrombolysis (IVT). However access to MTE remains restricted in some regions despite efforts to increase its availability. We performed an evaluation of national datasets to monitor improvements made in access to revascularization therapies for IS patients in Germany.

METHODS

We analyzed national datasets on German Diagnosis-Related Groups and structured quality reports by extracting information of patients admitted with stroke with and without IVT and MTE for the period of 2019-2021. Data from 2016 and limited data for 2022 were also included for comparison.

RESULTS

Admissions with ischemic stroke declined during the years of the COVID 19 pandemic by 4.5% from 227,258 in 2019 to 216,923 in 2021. IVT rates were stable with 16.3% being treated with IVT in 2019 and 2021. MTE rates continued to increase from 7.1 to 8.4% and the number of MTE centers increased by 14.8% in the same period. Over 87.3% of MTEs were performed in centers with a case volume exceeding 50 cases per year in 2021. The largest increase in the relative share of MTEs was seen in large MTE centers (n ≥ 200). Patient age for MTEs surpassed the age for IVTs in 2019 and the proportion of patients ≥ 80 years receiving MTE continued to increase. The proportion of regions in Germany with poor MTE rates (≤ 4.1%) decreased significantly from 2019 (12.3%) to 2021 (5.3%) (p < 0.001).

CONCLUSIONS

We found strong evidence that while IVT rates reached a temporary ceiling effect, both the absolute number of and access to MTEs continued to increase in Germany. Regional disparities have become less significant and the majority of MTEs are performed in centers with medium or high case volumes.

Performance of Thrombectomy-Capable, Comprehensive, and Primary Stroke Centers in Reperfusion Therapies for Acute Ischemic Stroke: Report From the Get With The Guidelines-Stroke Registry

BACKGROUND

The thrombectomy-capable stroke center (TSC) is a recently introduced intermediate tier of accreditation for hospitals at which patients with acute ischemic stroke receive care. The comparative quality and clinical outcomes of reperfusion therapies at TSCs, primary stroke centers (PSCs), and comprehensive stroke centers (CSCs) have not been well delineated.

METHODS

We conducted a retrospective, observational, cohort study from 2018 to 2020 that included patients with acute ischemic stroke who received endovascular thrombectomy (EVT) and intravenous thrombolysis reperfusion therapies at CSCs, TSCs, or PSCs. Participants were recruited from Get With The Guidelines-Stroke registry. Study end points included timeliness of intravenous thrombolysis and EVT, successful reperfusion, discharge destination, discharge mortality, and functional independence at discharge.

RESULTS

Among 84 903 patients, 48 682 received EVT, of whom 73% were treated at CSCs, 22% at PSCs, and 4% at TSCs. The median annual EVT volume was 76 for CSCs, 55 for TSCs, and 32 for PSCs. Patient differences by center status included higher National Institutes of Health Stroke Scale score, longer onset-to-arrival time, and higher transfer-in rates for CSCs, TSCs, and PSCs, respectively. In adjusted analyses, the likelihood of achieving the goal door-to-needle time was higher in CSCs compared with PSCs (odds ratio [OR], 1.39 [95% CI, 1.17-1.66]) and in TSCs compared with PSCs (OR, 1.45 [95% CI, 1.08-1.96]). Likewise, the odds of achieving the goal door-to-puncture time were higher in CSCs compared with PSCs (OR, 1.58 [95% CI, 1.13-2.21]). CSCs and TSCs also demonstrated better clinical efficacy outcomes compared with PSCs. The odds of discharge to home or rehabilitation were higher in CSCs compared with PSCs (OR, 1.18 [95% CI, 1.06-1.31]), whereas the odds of in-hospital mortality or discharge to hospice were lower in both CSCs compared with PSCs (OR, 0.87 [95% CI, 0.81-0.94]) and TSCs compared with PSCs (OR, 0.86 [95% CI, 0.75-0.98]). There were no significant differences in any of the quality-of-care metrics and clinical outcomes between TSCs and CSCs.

CONCLUSIONS

In this study representing national US practice, CSCs and TSCs exceeded PSCs in key quality-of-care reperfusion metrics and outcomes, whereas TSCs and CSCs demonstrated a similar performance. With more than one-fifth of all EVT procedures during the study period conducted at PSCs, it may be desirable to explore national initiatives aimed at facilitating the elevation of eligible PSCs to a higher certification status.

Most Promising Approaches to Improve Stroke Outcomes: The Stroke Treatment Academic Industry Roundtable XII Workshop

The Stroke Treatment Academic Industry Roundtable XII included a workshop to discuss the most promising approaches to improve outcome from acute stroke. The workshop brought together representatives from academia, industry, and government representatives. The discussion examined approaches in 4 epochs: pre-reperfusion, reperfusion, post-reperfusion, and access to acute stroke interventions. The participants identified areas of priority for developing new and existing treatments and approaches to improve stroke outcomes. Although many advances in acute stroke therapy have been achieved, more work is necessary for reperfusion therapies to benefit the most possible patients. Prioritization of promising approaches should help guide the use of resources and investigator efforts.

Change in Hospital Risk-standardized Stroke Mortality Performance With and Without the Passive Surveillance Stroke Severity Score

BACKGROUND

Adjustment for baseline stroke severity is necessary for accurate assessment of hospital performance. We evaluated whether adjusting for the Passive Surveillance Stroke SeVerity (PaSSV) score, a measure of stroke severity derived using administrative data, changed hospital-specific estimated 30-day risk-standardized mortality rate (RSMR) after stroke.

METHODS

We used linked administrative data to identify adults who were hospitalized with ischemic stroke or intracerebral hemorrhage across 157 hospitals in Ontario, Canada between 2014 and 2019. We fitted a random effects logistic regression model using Markov Chain Monte Carlo methods to estimate hospital-specific 30-day RSMR and 95% credible intervals with adjustment for age, sex, Charlson comorbidity index, and stroke type. In a separate model, we additionally adjusted for stroke severity using PaSSV. Hospitals were defined as low-performing, average-performing, or high-performing depending on whether the RSMR and 95% credible interval were above, overlapping, or below the cohort's crude mortality rate.

RESULTS

We identified 65,082 patients [48.0% were female, the median age (25th,75th percentiles) was 76 years (65,84), and 86.4% had an ischemic stroke]. The crude 30-day all-cause mortality rate was 14.1%. The inclusion of PaSSV in the model reclassified 18.5% (n=29) of the hospitals. Of the 143 hospitals initially classified as average-performing, after adjustment for PaSSV, 20 were reclassified as high-performing and 8 were reclassified as low-performing. Of the 4 hospitals initially classified as low-performing, 1 was reclassified as high-performing. All 10 hospitals initially classified as high-performing remained unchanged.

CONCLUSION

PaSSV may be useful for risk-adjusting mortality when comparing hospital performance. External validation of our findings in other jurisdictions is needed.

Neighbourhood deprivation, distance to nearest comprehensive stroke centre and access to endovascular thrombectomy for ischemic stroke: a population-based study

BACKGROUND

Endovascular thrombectomy (EVT) has revolutionized ischemic stroke care. We aimed to assess whether neighbourhood socioeconomic status is predictive of access to EVT after receipt of alteplase for ischemic stroke among patients living in Alberta, Canada, and whether this relation is mediated by the distance a person lives to the nearest comprehensive stroke centre (CSC).

METHODS

We performed a retrospective study including all people older than 18 years living in Alberta who were admitted to hospital with an ischemic stroke and who received intravenous alteplase treatment between Jan. 1, 2017, and Dec. 31, 2019. Data were obtained through administrative data sets. The primary outcome was treatment with EVT. We assigned neighbourhood deprivation quintile based on the Material and Social Deprivation Index. We used logistic regression modelling to assess for a relation between deprivation and treatment with EVT. We adjusted for age, sex, stroke severity and distance to the nearest CSC. We calculated the average causal mediation effect of distance to the nearest CSC on the relation between neighbourhood deprivation level and treatment with EVT.

RESULTS

The study cohort consisted of 1335 patients, of whom 181 (13.6%) had missing data and were excluded from the main regression analysis. Endovascular thrombectomy was performed or attempted in 314 patients (23.5%). In the primary model, patients from the most deprived neighbourhoods were less likely than those from less deprived neighbourhoods to have received EVT (adjusted odds ratio 0.43, 95% confidence interval 0.24 to 0.77). Neighbourhood deprivation level was not significantly associated with EVT when distance to the nearest CSC was included as a covariate. Mediation analysis suggested that 48% of the total effect that neighbourhood deprivation level had on the odds of receiving EVT was attributable to the distance a person lived from the nearest CSC.

INTERPRETATION

The results suggest that people from more deprived neighbourhoods in Alberta were less likely to be treated with EVT than those from less deprived neighbourhoods. Improving access to EVT for people living in remote locations may improve the equitable distribution of this treatment.

Insurance-Based Disparities in Stroke Center Access in California: A Network Science Approach

BACKGROUND

Our objectives were to determine whether there is an association between ischemic stroke patient insurance and likelihood of transfer overall and to a stroke center and whether hospital cluster modified the association between insurance and likelihood of stroke center transfer.

METHODS

This retrospective network analysis of California data included every nonfederal hospital ischemic stroke admission from 2010 to 2017. Transfers from an emergency department to another hospital were categorized based on whether the patient was discharged from a stroke center (primary or comprehensive). We used logistic regression models to examine the relationship between insurance (private, Medicare, Medicaid, uninsured) and odds of (1) any transfer among patients initially presenting to nonstroke center hospital emergency departments and (2) transfer to a stroke center among transferred patients. We used a network clustering method to identify clusters of hospitals closely connected through transfers. Within each cluster, we quantified the difference between insurance groups with the highest and lowest proportion of transfers discharged from a stroke center.

RESULTS

Of 332 995 total ischemic stroke encounters, 51% were female, 70% were ≥65 years, and 3.5% were transferred from the initial emergency department. Of 52 316 presenting to a nonstroke center, 3466 (7.1%) were transferred. Relative to privately insured patients, there were lower odds of transfer and of transfer to a stroke center among all groups (Medicare odds ratio, 0.24 [95% CI, 0.22-0.26] and 0.59 [95% CI, 0.50-0.71], Medicaid odds ratio, 0.26 [95% CI, 0.23-0.29] and odds ratio, 0.49 [95% CI, 0.38-0.62], uninsured odds ratio, 0.75 [95% CI, 0.63-0.89], and 0.72 [95% CI, 0.6-0.8], respectively). Among the 14 identified hospital clusters, insurance-based disparities in transfer varied and the lowest performing cluster (also the largest; n=2364 transfers) fully explained the insurance-based disparity in odds of stroke center transfer.

CONCLUSIONS

Uninsured patients had less stroke center access through transfer than patients with insurance. This difference was largely explained by patterns in 1 particular hospital cluster.

Higher Procedural Volumes Are Associated with Faster Treatment Times, Better Functional Outcomes, and Lower Mortality in Patients Undergoing Endovascular Treatment for Acute Ischemic Stroke

OBJECTIVE

We aimed to characterize the association of hospital procedural volumes with outcomes among acute ischemic stroke (AIS) patients undergoing endovascular therapy (EVT).

METHODS

This was a retrospective, observational cohort study using data prospectively collected from January 1, 2016 to December 31, 2019 in the Get with the Guidelines-Stroke registry. Participants were derived from a cohort of 60,727 AIS patients treated with EVT within 24 hours at 626 hospitals. The primary cohort excluded patients with pretreatment National Institutes of Health Stroke Scale (NIHSS) < 6, onset-to-treatment time > 6 hours, and interhospital transfers. There were 2 secondary cohorts: (1) the EVT metrics cohort excluded patients with missing data on time from door to arterial puncture and (2) the intravenous thrombolysis (IVT) metrics cohort only included patients receiving IVT ≤4.5 hours after onset.

RESULTS

The primary cohort (mean ± standard deviation age = 70.7 ± 14.8 years; 51.2% female; median [interquartile range] baseline NIHSS = 18.0 [13-22]; IVT use, 70.2%) comprised 21,209 patients across 595 hospitals. The EVT metrics cohort and IVT metrics cohort comprised 47,262 and 16,889 patients across 408 and 601 hospitals, respectively. Higher procedural volumes were significantly associated with higher odds (expressed as adjusted odds ratio [95% confidence interval] for every 10-case increase in volume) of discharge to home (1.03 [1.02-1.04]), functional independence at discharge (1.02 [1.01-1.04]), and lower rates of in-hospital mortality (0.96 [0.95-0.98]). All secondary measures were also associated with procedural volumes.

INTERPRETATION

Among AIS patients primarily presenting to EVT-capable hospitals (excluding those transferred from one facility to another and those suffering in-hospital strokes), EVT at hospitals with higher procedural volumes was associated with faster treatment times, better discharge outcomes, and lower rates of in-hospital mortality. ANN NEUROL 2023.

Performance of Thrombectomy-Capable, Comprehensive, and Primary Stroke Centers in Reperfusion Therapies for Acute Ischemic Stroke: Report from the Get With The Guidelines Stroke Registry: Stroke Outcomes Per Hospital Certification Status

Background

The thrombectomy-capable stroke center (TSC) is a recently introduced intermediate tier of accreditation for hospitals caring for patients with acute ischemic stroke (AIS). The comparative quality and clinical outcomes of reperfusion therapies at TSCs, primary stroke centers (PSCs), and comprehensive stroke centers (CSCs) has not been well delineated.

Methods

We conducted a retrospective, observational, cohort study from 2018-2020 that included patients with AIS who received endovascular (EVT) and/or intravenous (IVT) reperfusion therapies at CSC, TSC, or PSC. Participants were recruited from Get With The Guidelines-Stroke registry. Study endpoints included timeliness of IVT and EVT, successful reperfusion, discharge destination, discharge mortality, and functional independence at discharge.

Results

Among 84,903 included patients, 48,682 received EVT, of whom 73% were treated at CSCs, 22% at PSCs, and 4% at TSCs. The median annual EVT volume was 76 for CSCs, 55 for TSCs, and 32 for PSCs. Patient differences by center status included higher NIHSS, longer onset-to-arrival time, and higher transfer-in rates for CSC/TSC/PSC, respectively. In adjusted analyses, the likelihood of achieving the goal door-to-needle time was higher in CSCs compared to PSCs (OR 1.39; 95% CI 1.17-1.66) and in TSCs compared to PSCs (OR 1.45; 95% CI 1.08-1.96). Similarly, the odds of achieving the goal door-to-puncture time were higher in CSCs compared to PSCs (OR 1.58; 95% CI 1.13-2.21). CSCs and TSCs also demonstrated better clinical efficacy outcomes compared to PSCs. The odds of discharge to home or rehabilitation were higher in CSCs compared to PSCs (OR 1.18; 95% CI 1.06-1.31), while the odds of in-hospital mortality/discharge to hospice were lower in both CSCs compared to PSCs (OR 0.87; 95% CI 0.81-0.94) and TSCs compared to PSCs (OR 0.86; 95% CI 0.75-0.98). There were no significant differences in any of the quality-of-care metrics and clinical outcomes between TSCs and CSCs.

Conclusions

In this study representing national US practice, CSCs and TSCs exceeded PSCs in key quality-of-care reperfusion metrics and outcomes, whereas TSCs and CSCs demonstrated similar performance. Considering that over one-fifth of all EVT procedures during the study period were conducted at PSCs, it may be desirable to explore national initiatives aimed at facilitating the elevation of eligible PSCs to a higher certification status.

Recent trends in high-volume Medicare stroke thrombectomy provider characteristics

BACKGROUND

Intracranial mechanical thrombectomy (MT) is increasingly indicated for use in acute ischemic stroke patients. We analyzed recent trends in the characteristics and geographic distributions of physicians providing this service with frequency to Medicare beneficiaries.

METHODS

We linked public data sources to elucidate and visualize trends in high-volume MT providers between 2016 and 2019.

RESULTS

High-volume MT providers increased by 184% between 2016 and 2019. The number of neurosurgeons, neurologists, and radiologists in this physician population increased by 251%, 205%, and 139%, respectively. Male practitioners accounted for 96% of providers in the most recent year of analysis. International medical graduates accounted for roughly one-third of these physicians across all 4 years of analysis. As of 2019, the three states with the most high-volume MT providers were Florida, California, and Texas, accounting for 7%, 7%, and 6% of providers, respectively.

CONCLUSIONS

High-volume providers of MT services for Medicare beneficiaries represent a dynamic and rapidly expanding subset of physicians with diverse specialty backgrounds.

Mechanical Thrombectomy for Acute Ischemic Stroke

OBJECTIVE

Endovascular stroke therapy has greatly improved the ability to treat the deadliest and most disabling form of acute ischemic stroke. This article summarizes some of the recent innovations in this field and discusses likely future developments.

LATEST DEVELOPMENTS

At present, there is robust activity to improve all facets of care for patients with large vessel occlusion stroke, including better prehospital routing, more efficient in-hospital screening, expanding indications for thrombectomy eligibility, innovating novel thrombectomy devices, and improving the effects of recanalization on clinical outcomes. In addition, the integration of endovascular stroke therapy (EVT)-an emergent and frequently off-hours procedure that requires a specialized team of nurses, technologists, and physicians-into acute stroke care has transformed referral patterns, hospital accreditation pathways, and physician practices. The eligibility for the procedure will potentially continue to grow to include patients screened without advanced imaging, larger core infarcts, and more distal occlusions.

ESSENTIAL POINTS

In this review, we discuss the current state of EVT and its implications for practice, and present three cases that highlight some of the directions in which the field is moving.

Telestroke value through the eyes of emergency medicine providers: A counterfactual analysis

Objectives

Emergency Medicine (EM) provider experiences consulting telestroke (TS) are poorly studied. In this qualitative study, we aimed to determine how TS changes patient management and to measure TS effects on EM provider confidence with acute ischemic stroke (AIS) treatment.

Materials and methods

We designed a survey for EM providers querying perceptions of TS value, confidence with treating AIS, and counterfactuals regarding what EM providers would have done without TS. Eligible EM providers participated in an audio-visual TS consult within a 6-state TS network between 11/2016-11/2017.

Results

We received 48 surveys (response rate 43%). The most common reason (71%) for using TS was tPA eligibility expert opinion. Most EM providers (94%) thought the patient/family were satisfied with TS and none felt their medical knowledge was doubted because of using TS. EM providers had high confidence in diagnosing AIS (95%) and tPA decision-making (86%), but not in determining thrombectomy eligibility (10%). Among EM providers who administered tPA, 85% said tPA would not have been given without TS consultation. TS consultation changed patient diagnosis in 60% of all patients and treatment plans in 56% of non-stroke patients. Most EM providers (86%) had increased confidence in their knowledge of future stroke patient management. Nearly all TS consults (93%) resulted in EM providers being more likely to use TS again.

Conclusions

TS consult frequently results in both patient management change and increased EM knowledge of stroke management with increased likelihood of repeat usage. Discomfort in determining eligibility for thrombectomy points to educational opportunities.

Current territorial organization for access to revascularization therapies for acute ischemic stroke in the Veneto region (Italy) from 2017 to 2021

INTRODUCTION

To evaluate the access to treatments with intravenous thrombolysis (IVT) and/or mechanical thrombectomy (MT) in acute ischemic stroke patients admitted to stroke units (SUs) of Veneto region (Italy) according to current "hub-and-spoke" model from 2017 to 2021.

PATIENTS AND METHODS

We retrospectively analyzed data on treatments with IVT and/or MT for stroke patients admitted to the 23 SUs (6 Hubs and 17 Spokes) of the 6 macro-areas including 9 local sanitary units (LSUs) and 2 hospitals.

RESULTS

We reported 6093 treatments with IVT alone, 1114 with IVT plus MT, and 921 with MT alone. Number of stroke unit (SU) beds/100,000 inhabitants ranges from 2.3 to 2.8, and no difference was found among different macro-areas. Number of treatments/100,000 inhabitants/year ranges from 19 to 34 for IVT alone, from 2 to 7 for IVT plus MT, and from 2 to 5 for MT alone. Number of IVT alone/SU bed/year ranges from 9 to 21 in the Hub and from 6 to 12 in the Spokes. Rate of IVT plus MT in patients directly arrived in the same LSU's Hub ranges from 50 to 81%, likewise the one of MT alone ranges from 49 to 84%.

CONCLUSIONS

Treatment target rates of IVT and MT set by Action Plan for Stroke in Europe 2018-2030 has been globally exceeded in the Veneto region. However, the target rate of MT and access revascularization treatments is heterogeneous among different macro-areas. Further efforts should be made to homogenize the current territorial organization.

Time-to-care metrics in patients with interhospital transfer for mechanical thrombectomy in north-east Germany: Primary telestroke centers in rural areas vs. primary stroke centers in a metropolitan area

Background

Mechanical thrombectomy (MT) is highly effective in large vessel occlusion (LVO) stroke. In north-east Germany, many rural hospitals do not have continuous neurological expertise onsite and secondary transport to MT capable comprehensive stroke centers (CSC) is necessary. In metropolitan areas, small hospitals often have neurology departments, but cannot perform MT. Thus, interhospital transport to CSCs is also required. Here, we compare time-to-care metrics and outcomes in patients receiving MT after interhospital transfer from primary stroke centers (PCSs) to CSCs in rural vs. metropolitan areas.

Methods

Patients from ten rural telestroke centers (RTCs) and nine CSCs participated in this study under the quality assurance registry for thrombectomies of the Acute Neurological care in North-east Germany with TeleMedicine (ANNOTeM) telestroke network. For the metropolitan area, we included patients admitted to 13 hospitals without thrombectomy capabilities (metropolitan primary stroke centers, MPSCs) and transferred to two CSCs. We compared groups regarding baseline variables, time-to-care metrics, clinical, and technical outcomes.

Results

Between October 2018 and June 2022, 50 patients were transferred from RTCs within the ANNOTeM network and 42 from MPSCs within the Berlin metropolitan area. RTC patients were older (77 vs. 72 yrs, p = 0.05) and had more severe strokes (NIHSS 17 vs. 10 pts., p < 0.01). In patients with intravenous thrombolysis (IVT; 34.0 and 40.5%, respectively), time from arrival at the primary stroke center to start of IVT was longer in RTCs (65 vs. 37 min, p < 0.01). However, RTC patients significantly quicker underwent groin puncture at CSCs (door-to-groin time: 42 vs. 60 min, p < 0.01). Despite longer transport distances from RTCs to CSCs (55 vs. 22 km, p < 0.001), there was no significant difference of times between arrival at the PSC and groin puncture (210 vs. 208 min, p = 0.96). In adjusted analyses, there was no significant difference in clinical and technical outcomes.

Conclusion

Despite considerable differences in the setting of stroke treatment in rural and metropolitan areas, overall time-to-care metrics were similar. Targets of process improvement should be door-to-needle times in RTCs, transfer organization, and door-to-groin times in CSCs wherever such process times are above best-practice models.

An Overview of Telehealth in the Management of Cardiovascular Disease: A Scientific Statement From the American Heart Association

Telehealth enables the remote delivery of health care through telecommunication technologies and has substantially affected the evolving medical landscape. The COVID-19 pandemic accelerated the utilization of telehealth as health care professionals were forced to limit face-to-face in-person visits. It has been shown that information delivery, diagnosis, disease monitoring, and follow-up care can be conducted remotely, resulting in considerable changes specific to cardiovascular disease management. Despite increasing telehealth utilization, several factors such as technological infrastructure, reimbursement, and limited patient digital literacy can hinder the adoption of remote care. This scientific statement reviews definitions pertinent to telehealth discussions, summarizes the effect of telehealth utilization on cardiovascular and peripheral vascular disease care, and identifies obstacles to the adoption of telehealth that need to be addressed to improve health care accessibility and equity.

Characterizing reasons for stroke thrombectomy ineligibility among potential candidates transferred in a hub-and-spoke network

Background

Access to endovascular thrombectomy (EVT) is relatively limited. Hub-and-spoke networks seek to transfer appropriate large vessel occlusion (LVO) candidates to EVT-capable hubs. However, some patients are ineligible upon hub arrival, and factors that drive transfer inefficiencies are not well described. We sought to quantify EVT transfer efficiency and identify reasons for EVT ineligibility.

Methods

Consecutive EVT candidates presenting to 25 spokes from 2018-2020 with pre-transfer CTA-defined LVO and ASPECTS ≥6 were identified from a prospectively maintained database. Outcomes of interest included hub EVT, reasons for EVT ineligibility, and 90-day modified Rankin Scale (mRS) ≤2.

Results

Among 258 patients, the median age was 70 years (IQR 60-81); 50% were female. 56% were ineligible for EVT after hub arrival. Cited reasons were large established infarct (49%), mild symptoms (33%), recanalization (6%), distal occlusion (5%), sub-occlusive lesion (3%), and goals of care (3%). Late window patients [last known well (LKW) >6 hours] were more likely to be ineligible (67% vs 43%, P<0.0001). EVT ineligible patients were older (73 vs 68 years, p=0.04), had lower NIHSS (10 vs 16, p<0.0001), longer LKW-hub arrival time (8.4 vs 4.6 hours, p<0.0001), longer spoke Telestroke consult-hub arrival time (2.8 vs 2.2 hours, p<0.0001), and received less intravenous thrombolysis (32% vs 45%, p=0.04) compared to eligible patients. EVT ineligibility independently reduced the odds of 90-day mRS≤2 (aOR=0.26, 95%CI=0.12,0.56; p=0.001) when controlling for age, NIHSS, and LKW-hub arrival time.

Conclusions

Among patients transferred for EVT, there are multiple reasons for ineligibility upon hub arrival, with most excluded for infarct growth and mild symptoms. Understanding factors that drive transfer inefficiencies is important to improve EVT access and outcomes.

Measuring Stroke Quality: Methodological Considerations in Selecting, Defining, and Analyzing Quality Measures

Knowledge about stroke and its management is growing rapidly and stroke systems of care must adapt to deliver evidence-based care. Quality improvement initiatives are essential for translating knowledge from clinical trials and recommendations in guidelines into routine clinical practice. This review focuses on issues central to the measurement of the quality of stroke care, including selection and definition of quality measures, identification of the eligible patient cohorts, optimization of data quality, and considerations for data analysis and interpretation.

External validation of the Passive Surveillance Stroke Severity Indicator

BACKGROUND

The Passive Surveillance Stroke Severity (PaSSV) Indicator was derived to estimate stroke severity from variables in administrative datasets but has not been externally validated.

METHODS

We used linked administrative datasets to identify patients with first hospitalization for acute stroke between 2007-2018 in Alberta, Canada. We used the PaSSV indicator to estimate stroke severity. We used Cox proportional hazard models and evaluated the change in hazard ratios and model discrimination for 30-day and 1-year case fatality with and without PaSSV. Similar comparisons were made for 90-day home time thresholds using logistic regression. We also linked with a clinical registry to obtain National Institutes of Health Stroke Scale (NIHSS) and compared estimates from models without stroke severity, with PaSSV, and with NIHSS.

RESULTS

There were 28,672 patients with acute stroke in the full sample. In comparison to no stroke severity, addition of PaSSV to the 30-day case fatality models resulted in improvement in model discrimination (C-statistic 0.72 [95%CI 0.71-0.73] to 0.80 [0.79-0.80]). After adjustment for PaSSV, admission to a comprehensive stroke center was associated with lower 30-day case fatality (adjusted hazard ratio changed from 1.03 [0.96-1.10] to 0.72 [0.67-0.77]). In the registry sample (N = 1328), model discrimination for 30-day case fatality improved with the inclusion of stroke severity. Results were similar for 1-year case fatality and home time outcomes.

CONCLUSION

Addition of PaSSV improved model discrimination for case fatality and home time outcomes. The validity of PASSV in two Canadian provinces suggests that it is a useful tool for baseline risk adjustment in acute stroke.

Optimizing Prehospital Stroke Systems of Care-Reacting to Changing Paradigms (OPUS-REACH): a pragmatic registry of large vessel occlusion stroke patients to create evidence-based stroke systems of care and eliminate disparities in access to stroke care

Background

Large vessel occlusion (LVO) strokes are best treated with rapid endovascular therapy (EVT). There are two routes that LVO stroke patients can take to EVT therapy when transported by EMS: primary transport (ambulance transports directly to an endovascular stroke center (ESC) or secondary transport (EMS transports to a non-ESC then transfers for EVT). There is no clear evidence which path to care results in better functional outcomes for LVO stroke patients. To find this answer, an analysis of a large, real-world population of LVO stroke patients must be performed.

Methods

A pragmatic registry of LVO stroke patients from nine health systems across the United States. The nine health systems span urban and rural populations as well as the spectrum of socioeconomic statuses. We will use univariate and multivariate analysis to explore the relationships between type of EMS transport, socioeconomic factors, and LVO stroke outcomes. We will use geographic information systems and spatial analysis to examine the complex movements of patients in time and space. To detect an 8% difference between groups, with a 3:1 patient ratio of primary to secondary transports, 95% confidence and 80% power, we will need approximately 1600 patients.

The primary outcome is the patients with modified Rankin Scale (mRS) ≤ 2 at 90 days. Subgroup analyses include patients who receive intravenous thrombolysis and duration of stroke systems. Secondary analyses include socioeconomic factors associated with poor outcomes after LVO stroke.

Discussion

Using the data obtained from the OPUS-REACH registry, we will develop evidence based algorithms for prehospital transport of LVO stroke patients. Unlike prior research, the OPUS-REACH registry contains patient-level data spanning from EMS dispatch to ninety day functional outcomes. We expect that we will find modifiable factors and socioeconomic disparities associated with poor outcomes in LVO stroke. OPUS-REACH with its breadth of locations, detailed patient records, and multidisciplinary researchers will design the optimal prehospital stroke system of care for LVO stroke patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12883-022-02653-x.

The relationship between stroke system organization and disparities in access to stroke center care in California

Background

There are significant racial and ethnic disparities in receipt of reperfusion interventions for acute ischemic stroke. Our objective was to determine whether there are disparities in access to stroke center care by race or ethnicity that help explain differences in reperfusion therapy and to understand whether interhospital patient transfer plays a role in improving access.

Methods

Using statewide administrating data including all emergency department and hospital discharges in California from 2010 to 2017, we identified all acute ischemic stroke patients. Primary outcomes of interest included presentation to primary or comprehensive stroke center (PSC or CSC), interhospital transfer, discharge from PSC or CSC, and discharge from CSC alone. We used hierarchical logistic regression modeling to identify the relationship between patient‐ and hospital‐level characteristics and outcomes of interest.

Results

Of 336,247 ischemic stroke patients, 55.4% were non‐Hispanic White, 19.6% Hispanic, 10.6% non‐Hispanic Asian/Pacific Islander, and 10.3% non‐Hispanic Black. There was no difference in initial presentation to stroke center hospitals between groups. However, adjusted odds of reperfusion intervention, interhospital transfer and discharge from CSC did vary by race and ethnicity. Adjusted odds of interhospital transfer were lower among Hispanic (odds ratio [OR] 0.94, 95% confidence interval [CI] 0.89 to 0.98) and non‐Hispanic Asian/Pacific Islander patients (OR 0.84, 95% CI 0.79 to 0.90) and odds of discharge from a CSC were lower for Hispanic (OR 0.91, 95% CI 0.85 to 0.97) and non‐Hispanic Black patients (OR 0.74, 95% CI 0.67 to 0.81).

Conclusions

There are racial and ethnic disparities in reperfusion intervention receipt among stroke patients in California. Stroke system of care design, hospital resources, and transfer patterns may contribute to this disparity.

Mechanical Thrombectomy Access for All? Challenges in Increasing Endovascular Treatment for Acute Ischemic Stroke in the United States

Mechanical thrombectomy (MT) is the most effective treatment for selected patients with an acute ischemic stroke due to emergent large vessel occlusions (LVOs). There is an urgent need to identify and address challenges in access to MT to maximize the numbers of patients who can benefit from this treatment. Barriers in access to MT include delays in evaluation and accurate diagnosis of LVO leading to inappropriate triage, logistical delays related to availability of facilities and trained interventionalists, and financial hurdles that affect treatment reimbursement. Collection of regional data related to these barriers is critical to better understand current access gaps and a measurable access score to thrombectomy could be useful to plan local public health intervention.

Racial and Ethnic Disparities in Functional Outcome after Thrombectomy: A Cohort Study of an Integrated Stroke Network

OBJECTIVES

Previous studies have shown racial disparities in access to treatment and outcomes in ischemic stroke patients. We sought to define racial disparities in functional outcomes among ischemic stroke patients receiving endovascular thrombectomy (EVT).

MATERIALS AND METHODS

We performed a retrospective review of patients in our institution's prospectively collected stroke patient registry from 08/2015 to 06/2019 at 1 comprehensive and 2 thrombectomy-ready stroke centers. We reviewed patients aged ≥ 18 who received mechanical thrombectomy including only patients with race/ethnicity data belonging to the 3 largest race/ethnic groups: Non-Hispanic White (NHW), Non-Hispanic Black (NHB), and Hispanic (HIS). We compared baseline characteristics and performed multivariable logistic regression to evaluate differences in good functional outcome defined as 90-day modified Rankin score (90 day mRS 0-2) as the primary outcome. Secondary outcomes were discharge disposition, length of stay, and excellent functional outcome (90 day mRS 0-1). Results are given as OR [95% CI].

RESULTS

Among 666 patients that met inclusion criteria, 45% were NHW, 30% were NHB, and 19% were HIS. NHB and HIS patients were younger than NHW (average age NHB 62; HIS 64; and NHW 70; p < 0.001). Diabetes was more prevalent in NHB (32%, p = 0.02) and HIS (47%, p < 0.001) compared to NHW (23%). There were no significant racial differences in pre-morbid mRS, arrival NIHSS, tPA treatment rates. There was no difference in primary outcome by race comparing NHW to the other racial groups (OR 1.08 [0.68-1.72]) but compared to HIS patients, NHW had a higher likelihood of the secondary outcome of excellent functional outcome (aOR 2.23 [1.01-4.93]) defined as mRS 0-1.

CONCLUSIONS

In this study of over 600 patients treated with EVT, we did not find significant racial disparities in functional outcome except for less excellent functional outcome in HIS compared to NHW. Further study on disparities in post-acute stroke care is needed.