Blood Pressure Trajectories and Outcomes After Endovascular Thrombectomy for Acute Ischemic Stroke

BACKGROUND

Data on systolic blood pressure (SBP) trajectories in the first 24 hours after endovascular thrombectomy (EVT) in acute ischemic stroke are limited. We sought to identify these trajectories and their relationship to outcomes.

METHODS

We combined individual-level data from 5 studies of patients with acute ischemic stroke who underwent EVT and had individual blood pressure values after the end of the procedure. We used group-based trajectory analysis to identify the number and shape of SBP trajectories post-EVT. We used mixed effects regression models to identify associations between trajectory groups and outcomes adjusting for potential confounders and reported the respective adjusted odds ratios (aORs) and common odds ratios.

RESULTS

There were 2640 total patients with acute ischemic stroke included in the analysis. The most parsimonious model identified 4 distinct SBP trajectories, that is, general directional patterns after repeated SBP measurements: high, moderate-high, moderate, and low. Patients in the higher blood pressure trajectory groups were older, had a higher prevalence of vascular risk factors, presented with more severe stroke syndromes, and were less likely to achieve successful recanalization after the EVT. In the adjusted analyses, only patients in the high-SBP trajectory were found to have significantly higher odds of early neurological deterioration (aOR, 1.84 [95% CI, 1.20-2.82]), intracranial hemorrhage (aOR, 1.84 [95% CI, 1.31-2.59]), mortality (aOR, 1.75 [95% CI, 1.21-2.53), death or disability (aOR, 1.63 [95% CI, 1.15-2.31]), and worse functional outcomes (adjusted common odds ratio,1.92 [95% CI, 1.47-2.50]).

CONCLUSIONS

Patients follow distinct SBP trajectories in the first 24 hours after an EVT. Persistently elevated SBP after the procedure is associated with unfavorable short-term and long-term outcomes.

Association between blood pressure variability and outcomes after endovascular thrombectomy for acute ischemic stroke: An individual patient data meta-analysis

INTRODUCTION

Data on the association between blood pressure variability (BPV) after endovascular thrombectomy (EVT) for acute ischemic stroke (AIS) and outcomes are limited. We sought to identify whether BPV within the first 24 hours post EVT was associated with key stroke outcomes.

METHODS

We combined individual patient-data from five studies among AIS-patients who underwent EVT, that provided individual BP measurements after the end of the procedure. BPV was estimated as either systolic-BP (SBP) standard deviation (SD) or coefficient of variation (CV) over 24 h post-EVT. We used a logistic mixed-effects model to estimate the association [expressed as adjusted odds ratios (aOR)] between tertiles of BPV and outcomes of 90-day mortality, 90-day death or disability [modified Rankin Scale-score (mRS) > 2], 90-day functional impairment (⩾1-point increase across all mRS-scores), and symptomatic intracranial hemorrhage (sICH), adjusting for age, sex, stroke severity, co-morbidities, pretreatment with intravenous thrombolysis, successful recanalization, and mean SBP and diastolic-BP levels within the first 24 hours post EVT.

RESULTS

There were 2640 AIS-patients included in the analysis. The highest tertile of SBP-SD was associated with higher 90-day mortality (aOR:1.44;95% CI:1.08-1.92), 90-day death or disability (aOR:1.49;95% CI:1.18-1.89), and 90-day functional impairment (adjusted common OR:1.42;95% CI:1.18-1.72), but not with sICH (aOR:1.22;95% CI:0.76-1.98). Similarly, the highest tertile of SBP-CV was associated with higher 90-day mortality (aOR:1.33;95% CI:1.01-1.74), 90-day death or disability (aOR:1.50;95% CI:1.19-1.89), and 90-day functional impairment (adjusted common OR:1.38;95% CI:1.15-1.65), but not with sICH (aOR:1.33;95% CI:0.83-2.14).

CONCLUSIONS

BPV after EVT appears to be associated with higher mortality and disability, independently of mean BP levels within the first 24 h post EVT. BPV in the first 24 h may be a novel target to improve outcomes after EVT for AIS.

Risk of major adverse cardiovascular events and stroke associated with treatment with GLP-1 or the dual GIP/GLP-1 receptor agonist tirzepatide for type 2 diabetes: A systematic review and meta-analysis

INTRODUCTION

Mounting evidence suggests that glucagon-like-peptide-1 receptor-agonists (GLP-1 RAs) attenuate cardiovascular-risk in type-2 diabetes (T2DM). Tirzepatide is the first-in-class, dual glucose-dependent-insulinotropic-polypeptide GIP/GLP-1 RA approved for T2DM.

PATIENTS AND METHODS

A systematic review and meta-analysis of randomized-controlled clinical trials (RCTs) was performed to estimate: (i) the incidence of major adverse cardiovascular events (MACE); and (ii) incidence of stroke, fatal, and nonfatal stroke in T2DM-patients treated with GLP-1 or GIP/GLP-1 RAs (vs placebo).

RESULTS

Thirteen RCTs (9 and 4 on GLP-1 RAs and tirzepatide, respectively) comprising 65,878 T2DM patients were included. Compared to placebo, GLP-1RAs or GIP/GLP-1 RAs reduced MACE (OR: 0.87; 95% CI: 0.81-0.94; p < 0.01; I2 = 37%), all-cause mortality (OR: 0.88; 95% CI: 0.82-0.96; p < 0.01; I2 = 21%) and cardiovascular-mortality (OR: 0.88; 95% CI: 0.80-0.96; p < 0.01; I2 = 14%), without differences between GLP-1 versus GIP/GLP-1 RAs. Additionally, GLP-1 RAs reduced the odds of stroke (OR: 0.84; 95% CI: 0.76-0.93; p < 0.01; I2 = 0%) and nonfatal stroke (OR: 0.85; 95% CI: 0.76-0.94; p < 0.01; I2 = 0%), whereas no association between fatal stroke and GLP-1RAs was uncovered (OR: 0.80; 95% CI: 0.61-1.05; p = 0.105; I2 = 0%). In secondary analyses, GLP-1 RAs prevented ischemic stroke (OR: 0.74; 95% CI: 0.61-0.91; p < 0.01; I2 = 0%) and MACE-recurrence, but not hemorrhagic stroke (OR: 0.92; 95% CI: 0.51-1.66; p = 0.792; I2 = 0%). There was no association between GLP-1RAs or GIP/GLP-1 RAs and fatal or nonfatal myocardial infarction.

DISCUSSION AND CONCLUSION

GLP-1 and GIP/GLP-1 RAs reduce cardiovascular-risk and mortality in T2DM. While there is solid evidence that GLP-1 RAs significantly attenuate the risk of ischemic stroke in T2DM, dedicated RCTs are needed to evaluate the efficacy of novel GIP/GLP-1 RAs for primary and secondary stroke prevention.

Code ICH: A Call to Action

Intracerebral hemorrhage is the most serious type of stroke, leading to high rates of severe disability and mortality. Hematoma expansion is an independent predictor of poor functional outcome and is a compelling target for intervention. For decades, randomized trials aimed at decreasing hematoma expansion through single interventions have failed to meet their primary outcomes of statistically significant improvement in neurological outcomes. A wide range of evidence suggests that ultra-early bundled care, with multiple simultaneous interventions in the acute phase, offers the best hope of limiting hematoma expansion and improving functional recovery. Patients with intracerebral hemorrhage who fail to receive early aggressive care have worse outcomes, suggesting that an important treatment opportunity exists. This consensus statement puts forth a call to action to establish a protocol for Code ICH, similar to current strategies used for the management of acute ischemic stroke, through which early intervention, bundled care, and time-based metrics have substantially improved neurological outcomes. Based on current evidence, we advocate for the widespread adoption of an early bundle of care for patients with intracerebral hemorrhage focused on time-based metrics for blood pressure control and emergency reversal of anticoagulation, with the goal of optimizing the benefit of these already widely used interventions. We hope Code ICH will endure as a structural platform for continued innovation, standardization of best practices, and ongoing quality improvement for years to come.

Strokes Averted by Intravenous Thrombolysis: A Secondary Analysis of a Prospective, Multicenter, Controlled Trial of Mobile Stroke Units

OBJECTIVE

This study was undertaken to examine averted stroke in optimized stroke systems.

METHODS

This secondary analysis of a multicenter trial from 2014 to 2020 compared patients treated by mobile stroke unit (MSU) versus standard management. The analytical cohort consisted of participants with suspected stroke treated with intravenous thrombolysis. The main outcome was a tissue-defined averted stroke, defined as a final diagnosis of stroke with resolution of presenting symptoms/signs by 24 hours attributed to thrombolysis and no acute infarction/hemorrhage on imaging. An additional outcome was stroke with early symptom resolution, defined as a final diagnosis of stroke with resolution of presenting symptoms/signs by 24 hours attributed to thrombolysis.

RESULTS

Among 1,009 patients with a median last known well to thrombolysis time of 87 minutes, 159 (16%) had tissue-defined averted stroke and 276 (27%) had stroke with early symptom resolution. Compared with standard management, MSU care was associated with more tissue-defined averted stroke (18% vs 11%, adjusted odds ratio [aOR] = 1.82, 95% confidence interval [CI] = 1.13-2.98) and stroke with early symptom resolution (31% vs 21%, aOR = 1.74, 95% CI = 1.12-2.61). The relationships between thrombolysis treatment time and averted/early recovered stroke appeared nonlinear. Most models indicated increased odds for stroke with early symptom resolution but not tissue-defined averted stroke with earlier treatment. Additionally, younger age, female gender, hyperlipidemia, lower National Institutes of Health Stroke Scale, lower blood pressure, and no large vessel occlusion were associated with both tissue-defined averted stroke and stroke with early symptom resolution.

INTERPRETATION

In optimized stroke systems, 1 in 4 patients treated with thrombolysis recovered within 24 hours and 1 in 6 had no demonstrable brain injury on imaging. ANN NEUROL 2024;95:347-361.

Outcomes of patients with pre-existing disability managed by mobile stroke units: A sub-analysis of the BEST-MSU study

BACKGROUND

Few data exist on acute stroke treatment in patients with pre-existing disability (PD) since they are usually excluded from clinical trials. A recent trial of mobile stroke units (MSUs) demonstrated faster treatment and improved outcomes, and included PD patients.

AIM

To determine outcomes with tissue plasminogen activator (tPA), and benefit of MSU versus management by emergency medical services (EMS), for PD patients.

METHODS

Primary outcomes were utility-weighted modified Rankin Scale (uw-mRS). Linear and logistic regression models compared outcomes in patients with versus without PD, and PD patients treated by MSU versus standard management by EMS. Time metrics, safety, quality of life, and health-care utilization were compared.

RESULTS

Of the 1047 tPA-eligible ischemic stroke patients, 254 were with PD (baseline mRS 2-5) and 793 were without PD (baseline mRS 0-1). Although PD patients had worse 90-day uw-mRS, higher mortality, more health-care utilization, and worse quality of life than non-disabled patients, 53% returned to at least their baseline mRS, those treated faster had better outcome, and there was no increased bleeding risk. Comparing PD patients treated by MSU versus EMS, 90-day uw-mRS was 0.42 versus 0.36 (p = 0.07) and 57% versus 46% returned to at least their baseline mRS. There was no interaction between disability status and MSU versus EMS group assignment (p = 0.67) for 90-day uw-mRS.

CONCLUSION

PD did not prevent the benefit of faster treatment with tPA in the BEST-MSU study. Our data support inclusion of PD patients in the MSU management paradigm.

Robot-Assisted Transcranial Doppler Versus Transthoracic Echocardiography for Right to Left Shunt Detection

BACKGROUND

Right to left shunt (RLS), including patent foramen ovale, is a recognized risk factor for stroke. RLS/patent foramen ovale diagnosis is made by transthoracic echocardiography (TTE), which is insensitive, transesophageal echocardiography, which is invasive, and transcranial Doppler (TCD), which is noninvasive and accurate but scarce.

METHODS

We conducted a prospective, single-arm device clinical trial of robot-assisted TCD (raTCD) versus TTE for RLS diagnosis at 6 clinical sites in patients who presented with an event suspicious for embolic cerebrovascular ischemia from October 6, 2020 to October 20, 2021. raTCD was performed with standard TCD bubble study technique. TTE bubble study was performed per local standards. The primary outcome was rate of RLS detection by raTCD versus TTE.

RESULTS

A total of 154 patients were enrolled, 129 evaluable (intent to scan) and 121 subjects had complete data per protocol. In the intent to scan cohort, mean age was 60±15 years, 47% were women, and all qualifying events were diagnosed as ischemic stroke or transient ischemic attack. raTCD was positive for RLS in 82 subjects (64%) and TTE was positive in 26 (20%; absolute difference 43.4% [95% CI, 35.2%-52.0%]; P<0.001). On prespecified secondary analysis, large RLS was detected by raTCD in 35 subjects (27%) versus 13 (10%) by TTE (absolute difference 17.0% [95% CI, 11.5%-24.5%]; P<0.001). There were no serious adverse events.

CONCLUSIONS

raTCD was safe and ≈3 times more likely to diagnose RLS than TTE. TTE completely missed or underdiagnosed two thirds of large shunts diagnosed by raTCD. The raTCD device, used by health professionals with no prior TCD training, may allow providers to achieve the known sensitivity of TCD for RLS and patent foramen ovale detection without the need for an experienced operator to perform the test. Pending confirmatory studies, TCD appears to be the superior screen for RLS compared with TTE (funded by NeuraSignal).

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT04604015.

Stroke imaging modality for endovascular therapy in the extended window: systematic review and meta-analysis

BACKGROUND

In anterior circulation large vessel occlusion (LVO) in the extended time window, the guidelines recommend advanced imaging (ADVI) to select patients for endovascular therapy (EVT). However, questions remain regarding its availability and applicability in the real world. It is unclear whether an approach to the extended window EVT that does not use ADVI would be equivalent.

METHODS

In April 2022, a literature search was performed to identified randomized controlled trials (RCT) and observational studies describing 90-day outcomes. We performed a meta-analysis of the proportion of aggregate using a random effect to estimate rates of functional independence, defined as modified Rankin Scale (mRS) score ≤2 at 90 days, mean mRS, mortality and symptomatic intracranial hemorrhage (sICH) stratified by imaging modality.

RESULTS

Four RCTs and 28 observational studies were included. The pooled proportion of functional independence among patients selected by ADVI was 44% (95% CI 39% to 48%; I2=80%) and 48% (95% CI 41% to 55%; I2=75%) with non-contrast CT/CT angiography (NCCT/CTA) (p=0.36). Mean mRS with ADVI was 2.88 (95% CI 2.36 to 3.41; I2=0.0%) and 2.79 (95% CI 2.31 to 3.27; I2=0.0%) with NCCT (p=0.79). Mortality in patients selected by ADVI was 13% (95% CI 10% to 17%; I2=81%) and 16% (95% CI 12% to 22%; I2=69%) with NCCT (p=0.29). sICH with ADVI was 4% (95% CI 3% to 7%; I2=73%) and 6% with NCCT/CTA (95% CI 4% to 8%; I2=6%, p=0.27).

CONCLUSIONS

Our study suggests that, in anterior circulation LVO, the rates of functional independence may be similar when patients are selected using ADVI or NCCT for EVT in the extended time window. A simplified triage protocol does not seem to increase mortality or sICH. PROTOCOL REGISTRATION NUMBER: (PROSPERO ID: CRD42021236092).

Medical Management Versus Endovascular Treatment for Large-Vessel Occlusion Anterior Circulation Stroke With Low NIHSS

BACKGROUND

Endovascular treatment (EVT) for acute ischemic stroke (AIS) patients presenting with National Institutes of Health Stroke Scale score of 0 to 5 is common in clinical practice but has not yet been proven safe and effective. Our objective is to assess whether EVT on top of best medical treatment (BMT) in AIS patients with large-vessel occlusion of the anterior circulation presenting with mild symptoms is beneficial compared with BMT.

METHODS

We searched MEDLINE, SCOPUS, and reference lists of retrieved articles published until December 28, 2022. A systematic literature search was conducted to identify clinical trials or observational cohort studies evaluating patients with AIS due to anterior circulation large-vessel occlusion and admission National Institutes of Health Stroke Scale score ≤5 treated with EVT versus BMT alone. The primary outcome was excellent functional outcome (modified Rankin Scale score 0-1) at 3 months. The protocol had been registered before data collection (PROSPERO).

RESULTS

Eleven observational eligible studies were included in the meta-analysis, comprising a total of 2019 AIS patients with National Institutes of Health Stroke Scale score ≤5 treated with EVT versus 3171 patients treated with BMT. EVT was not associated with excellent functional outcome (risk ratio, 1.10 [95% CI, 0.93-1.31]). When stratified for different study design (per-protocol versus intention-to-treat), there were no significant subgroup differences. EVT was not associated with good functional outcome (modified Rankin Scale score 0-2; risk ratio, 1.01 [95% CI, 0.89-1.16]) or reduced disability at 3 months (common odds ratio, 0.92 [95% CI, 0.60-1.41]). Symptomatic intracranial hemorrhage was more common in the patients receiving EVT (risk ratio, 3.53 [95% CI, 2.35-5.31]). No correlation was found between EVT and mortality at 3 months (risk ratio, 1.34 [95% CI, 0.83-2.18]). The same overall associations were confirmed in the sensitivity analysis of studies that performed propensity score matching.

CONCLUSIONS

EVT appears equivalent to BMT for patients with anterior circulation large-vessel occlusion AIS with low baseline National Institutes of Health Stroke Scale, despite the increased risk for symptomatic intracranial hemorrhage.

REGISTRATION

URL: https://www.crd.york.ac.uk/PROSPERO/; Unique identifier: CRD42022334417.

Accuracy of the Society of Radiologists in Ultrasound (SRU) Carotid Doppler Velocity Criteria for Grading North American Symptomatic Carotid Endarterectomy Trial (NASCET) Stenosis: A Meta-Analysis

PURPOSE

The Society of Radiologists in Ultrasound (SRU) consensus panel proposed six Doppler velocity cut points for classifying internal carotid artery (ICA) stenosis of 50% and 70% according to the North American Symptomatic Carotid Endarterectomy Trial (NASCET) method. Their relative accuracies have not been compared.

MATERIALS AND METHODS

Meta-analysis performed following comprehensive literature review and identification of manuscripts with graphs of individual patient NASCET ICA stenosis measured by arteriography versus ICA peak-systolic velocity (PSV), end-diastolic velocity (EDV) and ICA PSV to common carotid artery (CCA) PSV. True positives, true negatives, false positives, and false negatives were calculated and used in two-level mixed effects models. Hierarchical summary receiver operating characteristic (ROC) curves were generated. Areas under the ROC curves were estimated.

RESULTS

Nine studies performed between 1993 and 2016 were identified after review of 337 manuscripts. There were 1738 bifurcation data points extracted for PSV, 1026 for EDV, and 775 for ICA/CCA ratio. The highest sensitivity was 96% (95% CI: 93%, 98%) for PSV of 125 cm/s (50% stenosis) and highest specificity 86% (95% CI: 71%, 93%) for PSV of 230 cm/s (70% stenosis). Areas under the ROC curves ranged from a high of 0.93 (95% CI: 0.92, 0.95) for PSV (50% stenosis) to a low of 0.86 (95% CI: 0.84, 0.88) for EDV (70% stenosis).

CONCLUSIONS

The SRU consensus Doppler cut points vary in their accuracies for predicting ICA stenosis. The PSV cut points have tradeoffs: high sensitivity/low specificity for 50% stenosis and high specificity/moderate sensitivity for 70% stenosis.

Reducing Ischemic Stroke in Diabetes: The Role of GLP-1 RAs

Stroke is a significant cause of mortality worldwide, and diabetes is an independent risk factor for ischemic stroke occurrence and recurrence. Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) lower the risk of ischemic stroke through beneficial effects on traditional stroke risk factors such as hyperglycemia, hypertension, and dyslipidemia. Primary care practitioners (PCPs) can play a substantial role in reducing ischemic stroke; studies have indicated that patients who have a PCP at the time of first stroke have a lower risk of stroke recurrence. Clinical practice guidelines recommend treating type 2 diabetes in patients with or at risk for cardiovascular (CV) disease with glucose-lowering agents with proven CV benefit, such as GLP-1 RAs and sodium-glucose cotransporter-2 (SGLT2) inhibitors. Based on meta-analyses of CV outcomes trials, GLP-1 RAs have a substantial and statistically significant benefit on ischemic stroke risk reduction, whereas SGLT2 inhibitors have a nonsignificant effect. The use of GLP-1 RAs, in addition to non-pharmacologic and pharmacologic management of traditional stroke risk factors, is a key component of complex therapy for ischemic stroke risk reduction.

Abstract WP6: Strokes Averted by Intravenous Thrombolysis: A Secondary Analysis of the BEST-MSU Trial

Introduction: While the goal of IV tissue plasminogen activator (TPA) is to prevent infarction, few data exist on averted stroke.

Methods: Secondary analysis of a multicenter trial from 2014-2020 comparing outcomes between patients treated for stroke by mobile stroke unit (MSU) vs standard care (SC). The analytical cohort were patients with suspected stroke treated with IV TPA. The primary outcome was a time-defined averted stroke diagnosis, defined as a final diagnosis of stroke with resolution of presenting symptoms/signs by 24 hours. The secondary outcome was a tissue-defined averted stroke diagnosis, defined as a final diagnosis of stroke with resolution of presenting symptoms/signs by 24 hours and no acute infarction/hemorrhage on imaging. We used multivariable logistic regression to evaluate associations between study exposures (demographics, comorbidities, stroke characteristics) and outcomes.

Results: Among 1009 patients with a median last known well-to-TPA time of 87 minutes, 276 patients (27%) had a time-defined averted stroke (31% MSU, 21% SC) and 159 patients (16%) had a tissue-defined averted stroke (18% MSU, 11% SC). Factors independently associated with time-defined averted stroke were younger age (OR, 0.98; 95% CI, 0.96-0.99), female sex (0R, 0.51; 95% CI, 0.36-0.74), hyperlipidemia (OR, 1.81, 95% CI, 1.24-2.64), normal premorbid function (0R, 2.22; 95% CI, 1.37-3.67), lower glucose (OR, 0.996; 95% CI, 0.993-0.999), lower MAP (OR, 0.991; 95% CI, 0.983-0.998), MSU care (OR, 1.77; 95% CI, 1.21-2.62), lower NIH stroke scale (OR, 0.89; 95% CI, 0.86-0.93), and no large vessel occlusion (LVO) (OR, 0.52; 95% CI, 0.32-0.83). For tissue-based averted stroke, younger age, female sex, hyperlipidemia, lower MAP, MSU treatment, lower NIH stroke scale, and no LVO were significantly associated.

Conclusion: In a modern acute stroke trial, one-in-four patients treated with TPA for stroke recovered within 24 hours and one-in-six had no demonstrable brain injury on imaging. Younger age, female sex, hyperlipidemia, lower MAP, MSU care, lower stroke severity, and no LVO may increase the odds of averting stroke.

Abstract WMP2: Acute Stroke Treatment In Patients With Pre-exiting Disability: A Secondary Analysis Of The BEST-MSU Trial

Background: Few data exists on acute stroke treatment in patients with pre-existing disability (PD) since they are usually excluded from clinical trials.

Methods: A pre-specified subgroup analysis of tPA-eligible patients with PD enrolled in a prospective multicenter trial of Mobile Stroke Units (MSUs) vs standard management by emergency medical services (EMS). All patients had baseline mRS scores. Co-primary outcomes were mean utility-weighted modified Rankin Scale score (uw-mRS) and return to baseline mRS at 90 days. Linear and logistic regression models compared outcomes in patients with vs without PD, and patients with PD treated by MSU vs EMS. Time metrics, safety, quality of life, and health-care utilization were also compared.

Results: Of 1047 patients, 254 had baseline mRS >= 2 (159 MSU, 95 EMS; 31% mRS 2, 52% mRS 3, 17% mRS 4). Compared to patients without disability, patients with PD were older, had higher NIHSS, more comorbidities, less often lived at home, were treated slower, and had less thrombectomy. Patients with PD had worse 90-day uw-mRS (0.39 vs 0.80), higher mortality, more health-care utilization and worse quality of life than patients without PD. However, rates of symptomatic intracranial hemorrhage and final diagnoses of stroke mimics were similar between groups, and 52% of patients with PD returned to their baseline mRS. Patients with PD treated within the first hour had better 90-day uw-mRS than those treated later (0.48 vs 0.36, p=0.01). Comparing patients with PD treated by MSU vs EMS, time from last-known-well to tPA bolus was shorter (82 vs 111 min), and 24% vs 0% were treated in the first hour. Among patients with PD, MSU patients had non-significantly better 90-day uw-mRS (0.41 vs 0.35, p=0.09) and higher rate of returning to baseline mRS (56% vs 44%, p=0.09) than EMS patients. There was no interaction between either time to treatment (p=0.24) or MSU vs EMS group assignment (p= 0.42), 90-day uw-mRS, and PD vs no disability status.

Conclusion: Although outcomes after stroke are less favorable in patients with vs without PD, in a large, controlled trial, we found no interaction between baseline disability and the benefit of MSU treatment. Our data support the earliest treatment of acute stroke patients regardless of premorbid functional status.

Abstract TMP65: Robot-assisted Transcranial Doppler Versus Transthoracic Echocardiography For Right To Left Shunt Detection: “Real World” First-look

Background: Right to left shunt (RLS), including patent foramen ovale (PFO), is a recognized risk factor for stroke. RLS/PFO diagnosis can be made by transthoracic echocardiography (TTE) or transcranial Doppler (TCD). A multicenter, prospectively enrolled device trial of robot-assisted TCD (raTCD) vs TTE for RLS detection (BUBL, NCT04604015) was completed. This demonstrated raTCD detecting all and large RLS at approximately 3 times the rate of TTE (primary outcome, any RLS: raTCD 64% vs TTE 20% [absolute difference 43.4% (95% CI 34.3%-52.5%), p < 0.001]). It is unknown if these results are generalizable to routine practice.

Methods: We conducted a multi-site retrospective review of prospectively collected “real-world” clinical data of raTCD for RLS diagnosis. All patients referred for a clinical study at the participating sites who underwent raTCD were included. raTCD was performed with standard TCD bubble study technique at all sites. Outcomes included demographics, rate of RLS detection, all and large (Spencer Logarithmic Scale ≥3), as well as “no window” rate. These results were compared to the results of BUBL with descriptive statistics and 2-sample proportion tests.

Results: There were 350 patients who underwent clinical raTCD across three participating sites. In this population, the mean age was 56 ± 13 years compared to 59 ± 14 years in BUBL (p = 0.03, 95% CI 0.20-5.49). Both cohorts were 46% female. The clinical population had any RLS on raTCD in 54% (189/350) compared to 64% in BUBL, which was not a significant difference (p= 0.14, 95% CI -0.02-0.18). Large RLS was detected in 26% (91/350) of the clinical population as compared to 28% in BUBL, which was also not a significant difference (p = 0.89, 95% CI -0.08-0.11). The “no window” rate in the clinical population was 5% (18/350), compared to 8% in BUBL (p = 0.39, 95% CI -0.03-0.08).

Conclusions: The same raTCD device that was safe and 3 times more likely to diagnose RLS than TTE in a device trial detected all and large RLS in clinical practice at a rate similar to that demonstrated in the device trial. These results further support the notion that raTCD may allow providers to achieve the known sensitivity of TCD for RLS and PFO detection without the need for an experienced operator, even in a “real world” clinical setting.

Clinical, Neuroimaging, and Genetic Markers in Cerebral Amyloid Angiopathy-Related Inflammation: A Systematic Review and Meta-Analysis

BACKGROUND

There are limited data regarding the prevalence of distinct clinical, neuroimaging and genetic markers among patients diagnosed with cerebral amyloid angiopathy-related inflammation (CAA-ri). We sought to determine the prevalence of clinical, radiological, genetic and cerebrospinal fluid biomarker findings in patients with CAA-ri.

METHODS

A systematic review and meta-analysis of published studies including patients with CAA-ri was conducted to determine the prevalence of clinical, neuroimaging, genetic and cerebrospinal fluid biomarker findings. Subgroup analyses were performed based on (1) prospective or retrospective study design and (2) CAA-ri diagnosis with or without available biopsy. We pooled the prevalence rates using random-effects models and assessed the heterogeneity using Cochran-Q and I²-statistics.

RESULTS

We identified 4 prospective and 17 retrospective cohort studies comprising 378 patients with CAA-ri (mean age, 71.5 years; women, 52%). The pooled prevalence rates were as follows: cognitive decline at presentation 70% ([95% CI, 54%-84%]; I²=82%), focal neurological deficits 55% ([95% CI, 40%-70%]; I²=82%), encephalopathy 54% ([95% CI, 39%-68%]; I²=43%), seizures 37% ([95% CI, 27%-49%]; I²=65%), headache 31% ([95% CI, 22%-42%]; I²=58%), T2/fluid-attenuated inversion recovery-hyperintense white matter lesions 98% ([95% CI, 93%-100%]; I²=44%), lobar cerebral microbleeds 96% ([95% CI, 92%-99%]; I²=25%), gadolinium enhancing lesions 54% ([95% CI, 42%-66%]; I²=62%), cortical superficial siderosis 51% ([95% CI, 34%-68%]; I²=77%) and lobar macrohemorrhage 40% ([95% CI, 11%-73%]; I²=88%). The prevalence rate of the ApoE (Apolipoprotein E) ε4/ε4 genotype was 34% ([95% CI, 17%-53%]; I²=76%). Subgroup analyses demonstrated no differences in these prevalence rates based on study design and diagnostic strategy.

CONCLUSIONS

Cognitive decline was the most common clinical feature. Hyperintense T2/fluid-attenuated inversion recovery white matter lesions and lobar cerebral microbleeds were by far the most prevalent neuroimaging findings. Thirty-four percent of patients with CAA-ri have homozygous ApoE ε4/ε4 genotype and scarce data exist regarding the cerebrospinal fluid biomarkers and its significance in these patients.

International beliefs and head positioning practices in patients with spontaneous hyperacute intracerebral hemorrhage

Background

Prior to the conduct of the Head Position in Stroke Trial (HeadPoST), an international survey (n = 128) revealed equipoise for selection of head position in acute ischemic stroke.

Objectives

We aimed to determine whether equipoise exists for head position in spontaneous hyperacute intracerebral hemorrhage (ICH) patients following HeadPoST.

Design

This is an international, web-distributed survey focused on head positioning in hyperacute ICH patients.

Methods

A survey was constructed to examine clinicians' beliefs and practices associated with head positioning of hyperacute ICH patients. Survey items were developed with content experts, piloted, and then refined before distributing through stroke listservs, social media, and purposive snowball sampling. Data were analyzed using descriptive statistics and χ² test.

Results

We received 181 responses representing 13 countries on four continents: 38% advanced practice providers, 32% bedside nurses, and 30% physicians; overall, participants had median 7 [interquartile range (IQR) = 3-12] years stroke experience with a median of 100 (IQR = 37.5-200) ICH admissions managed annually. Participants disagreed that HeadPoST provided 'definitive evidence' for head position in ICH and agreed that their 'written admission orders include 30-degree head positioning', with 54% citing hospital policies for this head position in hyperacute ICH. Participants were unsure whether head positioning alone could influence ICH longitudinal outcomes. Use of serial proximal clinical and technology measures during the head positioning intervention were identified by 82% as the most appropriate endpoints for future ICH head positioning trials.

Conclusion

Interdisciplinary providers remain unconvinced by HeadPoST results that head position does not matter in hyperacute ICH. Future trials examining the proximal effects of head positioning on clinical stability in hyperacute ICH are warranted.

Intravenous Thrombolysis Initiated Before Transfer for Endovascular Stroke Thrombectomy: A Systematic Review and Meta-analysis

BACKGROUND AND OBJECTIVE

The role of intravenous thrombolysis (IVT) in patients with large vessel occlusions (LVOs) administered prior to transfer from a primary stroke center (PCS) to a comprehensive stroke center (CSC) is questioned.

METHODS

We included observational studies of patients with an LVO receiving IVT at a PCS prior to their EVT transfer compared to those receiving EVT alone. Efficacy outcomes included excellent or good functional outcomes [modified Rankin Scale (mRS) scores of 0-1 or 0-2, respectively] and reduced disability (mRS shift analysis) at three months. Safety outcomes included symptomatic intracranial hemorrhage (sICH) within 48 hours and three-month all-cause mortality. Associations are reported with crude odds ratios (ORs) and adjusted ORs (aOR).

RESULTS

We identified 6 studies, including 1723 participants (mean age: 71 years, 51% women; 53% treated with IVT at a PSC). The mean onset-to-groin puncture time did not differ between the two groups (mean difference:-20 min, 95%CI:-115.89,76.04). Patients receiving IVT prior to transfer had higher odds of three-month reduced disability (common OR=1.98; 95%CI:1.17-3.35), excellent (OR=1.70,95%CI:1.28-2.26) and good (OR=1.62,95%CI:1.15-2.29) functional outcomes, with no increased sICH (OR=0.87,95%CI:0.54-1.39) or mortality (OR=0.55,95%CI:0.37-0.83) risks. In the adjusted analyses patients receiving IVT at a PSC had higher odds of excellent functional outcome (aOR=1.32,95%CI:1.00-1.74) and lower probability for mortality (aOR=0.50,95%CI:0.27-0.93).

DISCUSSION

LVO patients receiving IVT at a PSC prior to an EVT transfer have higher likelihood of excellent functional recovery and lower odds of mortality, with no increase in sICH and onset-to-groin puncture times, compared to those transferred for EVT without previously receiving IVT.

Association of Intraventricular Fibrinolysis With Clinical Outcomes in Intracerebral Hemorrhage: An Individual Participant Data Meta-Analysis

BACKGROUND

In patients with intracerebral hemorrhage (ICH), the presence of intraventricular hemorrhage constitutes a promising therapeutic target. Intraventricular fibrinolysis (IVF) reduces mortality, yet impact on functional disability remains unclear. Thus, we aimed to determine the influence of IVF on functional outcomes.

METHODS

This individual participant data meta-analysis pooled 1501 patients from 2 randomized trials and 7 observational studies enrolled during 2004 to 2015. We compared IVF versus standard of care (including placebo) in patients treated with external ventricular drainage due to acute hydrocephalus caused by ICH with intraventricular hemorrhage. The primary outcome was functional disability evaluated by the modified Rankin Scale (mRS; range: 0-6, lower scores indicating less disability) at 6 months, dichotomized into mRS score: 0 to 3 versus mRS: 4 to 6. Secondary outcomes included ordinal-shift analysis, all-cause mortality, and intracranial adverse events. Confounding and bias were adjusted by random effects and doubly robust models to calculate odds ratios and absolute treatment effects (ATE).

RESULTS

Comparing treatment of 596 with IVF to 905 with standard of care resulted in an ATE to achieve the primary outcome of 9.3% (95% CI, 4.4-14.1). IVF treatment showed a significant shift towards improved outcome across the entire range of mRS estimates, common odds ratio, 1.75 (95% CI, 1.39-2.17), reduced mortality, odds ratio, 0.47 (95% CI, 0.35-0.64), without increased adverse events, absolute difference, 1.0% (95% CI, -2.7 to 4.8). Exploratory analyses provided that early IVF treatment (≤48 hours) after symptom onset was associated with an ATE, 15.2% (95% CI, 8.6-21.8) to achieve the primary outcome.

CONCLUSIONS

As compared to standard of care, the administration of IVF in patients with acute hydrocephalus caused by intracerebral and intraventricular hemorrhage was significantly associated with improved functional outcome at 6 months. The treatment effect was linked to an early time window <48 hours, specifying a target population for future trials.

Yield of ASPECTS and collateral CTA Selection for mechanical thrombectomy within 6-24 hours from symptom onset in a hub and spoke system

BACKGROUND

Recent extended window trials support the benefit of mechanical thrombectomy in anterior circulation large vessel occlusions with clinical-radiographic dissociation. Using trial imaging criteria, 6% were found eligible for MT in the EW in a hub-and-spoke system. We examined the eligibility and outcomes in consecutive extended window-mechanical thrombectomy patients using more pragmatic selection criteria.

METHODS

We retrospectively analyzed single-institution data of anterior circulation large vessel occlusions patients presenting between 6-24 h who underwent mechanical thrombectomy based on a priori determined criteria including non-contrast CT head ASPECTS ≥ 6 and/or CTA collateral scores ASITN/SIR 2-4. Primary outcomes consisted of post-mechanical thrombectomy TICI 2b-3 and 3-month modified Rankin scores; safety outcomes consisted of in-hospital mortality and symptomatic intracerebral hemorrhage.

RESULTS

767 consecutive acute ischemic strokes patients presented within the 6-24 hour window, and of these 48 (6%) anterior circulation large vessel occlusions patients underwent mechanical thrombectomy. In this cohort the mean age was 63±17 years, 56% were male, the median NIHSS was 16 [IQR 10-19], the median ASPECTS was 9 (IQR 8-10), and 79% (n=38) had good CTA collaterals. Occlusions were primarily M1 MCA (46%), with 29% tandem occlusions. Successful recanalization (mTICI 2b or 3) was achieved in 73% (n=35), while 6% (n=3) of patients developed symptomatic intracerebral hemorrhage. In-hospital mortality was 25% (n=12) while 40% (n=19) achieved 3-month modified Rankin Scores 0-2.

CONCLUSIONS

Our data suggest the use of pragmatic imaging approach of ASPECTS ≥6 with CTA collateral grade in extended time window which is already established in most hospitals.

ASNM and ASN joint guidelines for transcranial Doppler ultrasonic monitoring: An update

Today, it seems prudent to reconsider how ultrasound technology can be used for providing intraoperative neurophysiologic monitoring that will result in better patient outcomes and decreased length and cost of hospitalization. An extensive and rapidly growing literature suggests that the essential hemodynamic information provided by transcranial Doppler (TCD) ultrasonography neuromonitoring (TCDNM) would provide effective monitoring modality for improving outcomes after different types of vascular, neurosurgical, orthopedic, cardiovascular, and cardiothoracic surgeries and some endovascular interventional or diagnostic procedures, like cardiac catheterization or cerebral angiography. Understanding, avoiding, and preventing peri- or postoperative complications, including neurological deficits following abovementioned surgeries, endovascular intervention, or diagnostic procedures, represents an area of great public and economic benefit for society, especially considering the aging population. The American Society of Neurophysiologic Monitoring and American Society of Neuroimaging Guidelines Committees formed a joint task force and developed updated guidelines to assist in the use of TCDNM in the surgical and intensive care settings. Specifically, these guidelines define (1) the objectives of TCD monitoring; (2) the responsibilities and behaviors of the neurosonographer during monitoring; (3) instrumentation and acquisition parameters; (4) safety considerations; (5) contemporary rationale for TCDNM; (6) TCDNM perspectives; and (7) major recommendations.

Predictors of early neurologic deterioration (END) following stroke thrombectomy

BACKGROUND

Early neurologic deterioration (END) following ischemic stroke is a serious event and is associated with poor outcomes. However, the incidence and predictors of END after stroke thrombectomy for emergent large vessel occlusion are largely unknown.

METHODS

The baseline characteristics of patients enrolled in the COMPASS trial (NCT02466893) were analyzed. The primary outcome was worsening of ≥4 National Institutes of Health Stroke Scale (NIHSS) points 24 hours post thrombectomy (4+ END₂₄) and the secondary outcome was deterioration of ≥2 points (2+ END₂₄).

RESULTS

Among 270 patients, 27 (10%) developed 4+ END₂₄ and 42 (16%) had 2+ END₂₄. Those with 4+ END₂₄ were older (76.4±12.9 vs 70.9±12.9 years; p=0.04), had a higher prevalence of hypertension (96% vs 69%; p=0.003), diabetes (41% vs 27%; p=0.13) and higher pretreatment systolic blood pressure (SBP) (170.4±32.6 vs 157.6±28.1 mmHg; p=0.03). More 4+ END₂₄ patients had failed reperfusion: Thrombolysis in Cerebral Infarction ≤2a (26% vs 8%; p=0.003). In unadjusted analysis, older patients and those with hypertension, diabetes, elevated SBP and failed reperfusion had higher odds of 4+ END₂₄. In adjusted analysis, age increase by 5 years led to an increase in 4+ END₂₄ of 28%, diabetes increased odds of 2.6 and failed reperfusion increased odds of 4.5. In the multivariable analysis for the secondary outcome, age (OR 1.33; 95% CI 1.109 to 1.593), diabetes (OR 2.7; 95% CI 1.247 to 5.764) and failed reperfusion (OR 7.2; 95% CI 0.055 to 0.349) were also significant predictors of 2+ END₂₄.

CONCLUSIONS

Older patients with acute ischemic stroke who have a history of diabetes or hypertension, with elevated pretreatment SBP and failed reperfusion are at a higher risk of END following stroke thrombectomy for emergent large vessel occlusion.

Prolonged Cardiac Monitoring and Stroke Recurrence: A Meta-analysis

BACKGROUND AND OBJECTIVES

Prolonged poststroke cardiac rhythm monitoring (PCM) reveals a substantial proportion of patients with ischemic stroke (IS) with atrial fibrillation (AF) not detected by conventional rhythm monitoring strategies. We evaluated the association between PCM and the institution of stroke preventive strategies and stroke recurrence.

METHODS

We searched MEDLINE and SCOPUS databases to identify studies reporting stroke recurrence rates in patients with history of recent IS or TIA receiving PCM compared with patients receiving conventional cardiac rhythm monitoring. Pairwise meta-analyses were performed under the random effects model. To explore for differences between the monitoring strategies, we combined direct and indirect evidence for any given pair of monitoring devices assessed within a randomized controlled trial (RCT).

RESULTS

We included 8 studies (5 RCTs, 3 observational; 2,994 patients). Patients receiving PCM after their index event had a higher rate of AF detection and anticoagulant initiation in RCTs (risk ratio [RR] 3.91, 95% CI 2.54-6.03; RR 2.16, 95% CI 1.66-2.80, respectively) and observational studies (RR 2.06, 95% CI 1.57-2.70; RR 2.01, 95% CI 1.43-2.83, respectively). PCM was associated with a lower risk of recurrent stroke during follow-up in observational studies (RR 0.29, 95% CI 0.15-0.59), but not in RCTs (RR 0.72, 95% CI 0.49-1.07). In indirect analyses of RCTs, the likelihood of AF detection and anticoagulation initiation was higher for implantable loop recorders compared with Holter monitors and external loop recorders.

DISCUSSION

PCM after an IS or TIA can lead to higher rates of AF detection and anticoagulant initiation. There is no solid RCT evidence supporting that PCM may be associated with lower stroke recurrence risk.

The Mobile Stroke Unit Nurse: An International Exploration of Their Scope of Practice, Education, and Training

ABSTRACT

BACKGROUND: Mobile stroke units (MSUs) are ambulance-based prehospital stroke care services. Through immediate roadside assessment and onboard brain imaging, MSUs provide faster stroke management with improved patient outcomes. Mobile stroke units have enabled the development of expanded scope of practice for stroke nurses; however, there is limited published evidence about these evolving prehospital acute nursing roles. AIMS: The aim of this study was to explore the expanded scope of practice of nurses working on MSUs by identifying MSUs with onboard nurses; describing the roles and responsibilities, training, and experience of MSU nurses, through a search of the literature; and describing 2 international MSU services incorporating nurses from Memphis, Tennessee, and Melbourne, Australia. METHODS: We searched PubMed, CINAHL, and the Joanna Briggs Institute Evidence-Based Practice database using the terms "mobile stroke unit" and "nurse." Existing MSUs were identified through the PRE-hospital Stroke Treatment Organization to determine models that involved nurses. We describe 2 MSUs involving nurses: one in Memphis and one in Melbourne, led by 2 of our authors. RESULTS: Ninety articles were found describing 15 MSUs; however, staffing details were lacking, and it is unknown how many employ nurses. Nine articles described the role of the nurse, but role specifics, training, and expertise were largely undocumented. The MSU in Memphis, the only unit to be staffed exclusively by onboard nurse practitioners, is supported by a neurologist who consults via telephone. The Melbourne MSU plans to trial a nurse-led telemedicine model in the near future. CONCLUSION: We lack information on how many MSUs employ nurses, and the nurses' scope of practice, training, and expertise. Expert stroke nurse practitioners can safely perform many of the tasks undertaken by the onboard neurologist, making a nurse-led telemedicine model an effective and potentially cost-effective model that should be considered for all MSUs.

Prevalence of Clinical and Neuroimaging Markers in Cerebral Amyloid Angiopathy: A Systematic Review and Meta-Analysis

BACKGROUND

Limited data exist regarding the prevalence of clinical and neuroimaging manifestations among patients diagnosed with cerebral amyloid angiopathy (CAA). We sought to determine the prevalence of clinical phenotypes and radiological markers in patients with CAA.

METHODS

Systematic review and meta-analysis of studies including patients with CAA was conducted to primarily assess the prevalence of clinical phenotypes and neuroimaging markers as available in the included studies. Sensitivity analyses were performed based on the (1) retrospective or prospective study design and (2) probable or unspecified CAA status. We pooled the prevalence rates using random-effects models and assessed the heterogeneity using the Cochran Q and I² statistics.

RESULTS

We identified 12 prospective and 34 retrospective studies including 7159 patients with CAA. The pooled prevalence rates were cerebral microbleeds (52% [95% CI, 43%-60%]; I²=93%), cortical superficial siderosis (49% [95% CI, 38%-59%]; I²=95%), dementia or mild cognitive impairment (50% [95% CI, 35%-65%]; I²=97%), intracerebral hemorrhage (ICH; 44% [95% CI, 27%-61%]; I²=98%), transient focal neurological episodes (48%; 10 studies [95% CI, 29%-67%]; I²=97%), lacunar infarcts (30% [95% CI, 25%-36%]; I²=78%), high grades of perivascular spaces located in centrum semiovale (56% [95% CI, 44%-67%]; I²=88%) and basal ganglia (21% [95% CI, 2%-51%]; I²=98%), and white matter hyperintensities with moderate or severe Fazekas score (53% [95% CI, 40%-65%]; I²=91%). The only neuroimaging marker that was associated with higher odds of recurrent ICH was cortical superficial siderosis (odds ratio, 1.57 [95% CI, 1.01-2.46]; I²=47%). Sensitivity analyses demonstrated a higher prevalence of ICH (53% versus 16%; P=0.03) and transient focal neurological episodes (57% versus 17%; P=0.03) among retrospective studies compared with prospective studies. No difference was documented between the prevalence rates based on the CAA status.

CONCLUSIONS

Approximately one-half of hospital-based cohort of CAA patients was observed to have cerebral microbleeds, cortical superficial siderosis, mild cognitive impairment, dementia, ICH, or transient focal neurological episodes. Cortical superficial siderosis was the only neuroimaging marker that was associated with higher odds of ICH recurrence. Future population-based studies among well-defined CAA cohorts are warranted to corroborate our findings.

Abstract WP179: Impact Of Different Cardiac Rhythm Monitoring Strategies On Secondary Stroke Prevention: A Systematic Review And Network Meta-analysis Of Randomized Controlled Clinical Trials

Background and Purpose: Prolonged cardiac rhythm monitoring can reveal a substantial proportion of ischemic stroke (IS) patients with atrial fibrillation (AF). We sought to evaluate the potential utility of available prolonged cardiac rhythm monitoring strategies with respect to secondary stroke prevention.

Methods: We searched Medline and Scopus databases to identify randomized controlled clinical trials (RCTs) comparing AF detection, anticoagulation initiation and stroke recurrence rates in patients with history of recent IS or transient ischemic attack (TIA) receiving cardiac rhythm monitoring with implantable loop recorders (ILRs), 30-days external loop recorders or Holter monitors. We performed a network meta-analysis to combine direct and indirect evidence for any given pair of monitoring devices that were evaluated within a trial and reported effect estimates with risk ratios (RRs) and corresponding 95% confidence intervals (95%CIs).

Results: We identified 5 RCTs including a total of 2202 patients (mean age 68 years, 40% women). In indirect analyses the likelihood of AF detection and anticoagulation initiation was higher for both ILR (RR=8.48, 95%CI: 3.41, 21.06; RR=3.29, 95%CI: 1.70-6.39) and external loop recorders (RR=3.06, 95%CI: 1.66, 5.61; RR=1.63, 95%CI: 1.03-2.58) compared to Holter devices. The probability of AF detection and anticoagulation initiation was lower for Holter and external loop recorders compared to ILR devices (RR=0.36, 95%CI: 0.15, 0.85 and RR=0.50, 95%CI: 0.25-0.98, respectively). No difference in the risk of stroke recurrence was found in the indirect comparisons of different cardiac rhythm monitoring strategies.

Conclusion: The likelihood of AF detection and anticoagulation initiation after an ischemic stroke or TIA is higher with ILRs compared to both external loop recorders and Holter devices.

Prospective Interventions to Reduce Stroke Care Variation in a Hub-and-Spokes System

BACKGROUND

Care variation reduction (CVR) is a central objective of quality management to decrease wasted spending.

OBJECTIVE

To analyze stroke care variation at a hub-and-spokes system and determine interventions to prospectively reduce unwarranted variation.

METHODS

In this prospective cohort single arm intervention study providers were blinded to pre-specified endpoints. Care variation was measured for DRGs 61-66 and 69 in USD, and severity level by Case Mix Index (CMI) by provider. A multi-disciplinary task force chaired by Vascular Neurologist analyzed data extracted from Crimson, a patient centric data analysis tool, and determined interventions. The primary measure outcome was change in CMI post intervention.

RESULTS

Annualized baseline care variation was $ 0.7-1.2M (2017) in a drip-and-ship thrombolytic treatment model within the hub-and-spokes system. Pharmacy expenses contributed to 42% of variation followed by laboratory 12%, physical therapy 11%, supplies 11% and imaging 9%. Interventions to achieve CVR were prospectively implemented in 2018 and CVR was measured in January 2019. Based on 2017 CMI of 1.28, the goal of intervention was set to achieve 7% increase to 1.37 with projected increased revenue of $774,144. After implementation of interventions the actual achieved average CMI in 2018 was 1.40 paralleled by improvement in secondary outcomes of length of stay, observed over expected mortality and re-admission.

CONCLUSIONS

A drip-and-ship stroke model within a single hub-and-spokes healthcare system can achieve substantial reduction in care variation and associated cost along with improvement in patient care indicators.

Blood Pressure After Endovascular Thrombectomy and Outcomes in Patients With Acute Ischemic Stroke: An Individual Patient Data Meta-analysis

OBJECTIVE

To explore the association between blood pressure (BP) levels after endovascular thrombectomy (EVT) and the clinical outcomes of acute ischemic stroke (AIS) patients with large vessel occlusion (LVO).

METHODS

A study was eligible if it enrolled AIS patients older than 18 years, with an LVO treated with either successful or unsuccessful EVT, and provided either individual or mean 24-hour systolic BP values after the end of the EVT procedure. Individual patient data from all studies were analyzed using a generalized linear mixed-effects model.

RESULTS

A total of 5874 patients (mean age: 69±14 years, 50% women, median NIHSS on admission: 16) from 7 published studies were included. Increasing mean systolic BP levels per 10 mm Hg during the first 24 hours after the end of the EVT were associated with a lower odds of functional improvement (unadjusted common OR=0.82, 95%CI:0.80-0.85; adjusted common OR=0.88, 95%CI:0.84-0.93) and modified Ranking Scale score≤2 (unadjusted OR=0.82, 95%CI:0.79-0.85; adjusted OR=0.87, 95%CI:0.82-0.93), and a higher odds of all-cause mortality (unadjusted OR=1.18, 95%CI:1.13-1.24; adjusted OR=1.15, 95%CI:1.06-1.23) at 3 months. Higher 24-hour mean systolic BP levels were also associated with an increased likelihood of early neurological deterioration (unadjusted OR=1.14, 95%CI:1.07-1.21; adjusted OR=1.14, 95%CI:1.03-1.24) and a higher odds of symptomatic intracranial hemorrhage (unadjusted OR=1.20, 95%CI:1.09-1.29; adjusted OR=1.20, 95%CI:1.03-1.38) after EVT.

CONCLUSION

Increased mean systolic BP levels in the first 24 hours after EVT are independently associated with a higher odds of symptomatic intracranial hemorrhage, early neurological deterioration, three-month mortality, and worse three-month functional outcomes.

Predicting Parkinson's Disease and Its Pathology via Simple Clinical Variables

Background:

Parkinson’s disease (PD) is a chronic, disabling neurodegenerative disorder.

Objective:

To predict a future diagnosis of PD using questionnaires and simple non-invasive clinical tests.

Methods:

Participants in the prospective Kuakini Honolulu-Asia Aging Study (HAAS) were evaluated biannually between 1995–2017 by PD experts using standard diagnostic criteria. Autopsies were sought on all deaths. We input simple clinical and risk factor variables into an ensemble-tree based machine learning algorithm and derived models to predict the probability of developing PD. We also investigated relationships of predictive models and neuropathologic features such as nigral neuron density.

Results:

The study sample included 292 subjects, 25 of whom developed PD within 3 years and 41 by 5 years. 116 (46%) of 251 subjects not diagnosed with PD underwent autopsy. Light Gradient Boosting Machine modeling of 12 predictors correctly classified a high proportion of individuals who developed PD within 3 years (area under the curve (AUC) 0.82, 95%CI 0.76–0.89) or 5 years (AUC 0.77, 95%CI 0.71–0.84). A large proportion of controls who were misclassified as PD had Lewy pathology at autopsy, including 79%of those who died within 3 years. PD probability estimates correlated inversely with nigral neuron density and were strongest in autopsies conducted within 3 years of index date (r = –0.57, p < 0.01).

Conclusion:

Machine learning can identify persons likely to develop PD during the prodromal period using questionnaires and simple non-invasive tests. Correlation with neuropathology suggests that true model accuracy may be considerably higher than estimates based solely on clinical diagnosis.

Prospective, Multicenter, Controlled Trial of Mobile Stroke Units

BACKGROUND

Mobile stroke units (MSUs) are ambulances with staff and a computed tomographic scanner that may enable faster treatment with tissue plasminogen activator (t-PA) than standard management by emergency medical services (EMS). Whether and how much MSUs alter outcomes has not been extensively studied.

METHODS

In an observational, prospective, multicenter, alternating-week trial, we assessed outcomes from MSU or EMS management within 4.5 hours after onset of acute stroke symptoms. The primary outcome was the score on the utility-weighted modified Rankin scale (range, 0 to 1, with higher scores indicating better outcomes according to a patient value system, derived from scores on the modified Rankin scale of 0 to 6, with higher scores indicating more disability). The main analysis involved dichotomized scores on the utility-weighted modified Rankin scale (≥0.91 or <0.91, approximating scores on the modified Rankin scale of ≤1 or >1) at 90 days in patients eligible for t-PA. Analyses were also performed in all enrolled patients.

RESULTS

We enrolled 1515 patients, of whom 1047 were eligible to receive t-PA; 617 received care by MSU and 430 by EMS. The median time from onset of stroke to administration of t-PA was 72 minutes in the MSU group and 108 minutes in the EMS group. Of patients eligible for t-PA, 97.1% in the MSU group received t-PA, as compared with 79.5% in the EMS group. The mean score on the utility-weighted modified Rankin scale at 90 days in patients eligible for t-PA was 0.72 in the MSU group and 0.66 in the EMS group (adjusted odds ratio for a score of ≥0.91, 2.43; 95% confidence interval [CI], 1.75 to 3.36; P<0.001). Among the patients eligible for t-PA, 55.0% in the MSU group and 44.4% in the EMS group had a score of 0 or 1 on the modified Rankin scale at 90 days. Among all enrolled patients, the mean score on the utility-weighted modified Rankin scale at discharge was 0.57 in the MSU group and 0.51 in the EMS group (adjusted odds ratio for a score of ≥0.91, 1.82; 95% CI, 1.39 to 2.37; P<0.001). Secondary clinical outcomes generally favored MSUs. Mortality at 90 days was 8.9% in the MSU group and 11.9% in the EMS group.

CONCLUSIONS

In patients with acute stroke who were eligible for t-PA, utility-weighted disability outcomes at 90 days were better with MSUs than with EMS. (Funded by the Patient-Centered Outcomes Research Institute; BEST-MSU ClinicalTrials.gov number, NCT02190500.).

Sonothrombolysis in Patients With Acute Ischemic Stroke With Large Vessel Occlusion: An Individual Patient Data Meta-Analysis

BACKGROUND AND PURPOSE

Evidence about the utility of ultrasound-enhanced thrombolysis (sonothrombolysis) in patients with acute ischemic stroke (AIS) is conflicting. We aimed to evaluate the safety and efficacy of sonothrombolysis in patients with AIS with large vessel occlusion, by analyzing individual patient data of available randomized-controlled clinical trials.

METHODS

We included all available randomized-controlled clinical trials comparing sonothrombolysis with or without addition of microspheres (treatment group) to intravenous thrombolysis alone (control group) in patients with AIS with large vessel occlusion. The primary outcome measure was the rate of complete recanalization at 1 to 36 hours following intravenous thrombolysis initiation. We present crude odds ratios (ORs) and ORs adjusted for the predefined variables of age, sex, baseline stroke severity, systolic blood pressure, and onset-to-treatment time.

RESULTS

We included 7 randomized controlled clinical trials that enrolled 1102 patients with AIS. A total of 138 and 134 confirmed large vessel occlusion patients were randomized to treatment and control groups respectively. Patients randomized to sonothrombolysis had increased odds of complete recanalization compared with patients receiving intravenous thrombolysis alone (40.3% versus 22.4%; OR, 2.17 [95% CI, 1.03-4.54]; adjusted OR, 2.33 [95% CI, 1.02-5.34]). The likelihood of symptomatic intracranial hemorrhage was not significantly different between the 2 groups (7.3% versus 3.7%; OR, 2.03 [95% CI, 0.68-6.11]; adjusted OR, 2.55 [95% CI, 0.76-8.52]). No differences in the likelihood of asymptomatic intracranial hemorrhage, 3-month favorable functional and 3-month functional independence were documented.

CONCLUSIONS

Sonothrombolysis was associated with a nearly 2-fold increase in the odds of complete recanalization compared with intravenous thrombolysis alone in patients with AIS with large vessel occlusions. Further study of the safety and efficacy of sonothrombolysis is warranted.

High-resolution CT with arch/neck/head CT angiography on a mobile stroke unit

BACKGROUND

Mobile stroke units (MSUs) performance dependability and diagnostic yield of 16-slice, ultra-fast CT with auto-injection angiography (CTA) of the aortic arch/neck/circle of Willis has not been previously reported.

METHODS

We performed a prospective observational study of the first-of-its kind MSU equipped with high resolution, 16-slice CT with multiphasic CTA. Field CT/CTA was performed on all suspected stroke patients regardless of symptom severity or resolution. Performance dependability, efficiency and diagnostic yield over 365 days was quantified.

RESULTS

1031 MSU emergency activations occurred; of these, 629 (61%) were disregarded with unrelated diagnoses, and 402 patients transported: 245 (61%) ischemic or hemorrhagic stroke, 17 (4%) transient ischemic attack, 140 (35%) other neurologic emergencies. Total time from non-contrast CT/CTA start to images ready for viewing was 4.0 (IQR 3.5-4.5) min. Hemorrhagic stroke totaled 24 (10%): aneurysmal subarachnoid hemorrhage 3, hemorrhagic infarct 1, and 20 intraparenchymal hemorrhages (median intracerebral hemorrhage score was 2 (IQR 1-3), 4 (20%) spot sign positive). In 221 patients with ischemic stroke, 73 (33%) received alteplase with 31.5% treated within 60 min of onset. CTA revealed large vessel occlusion in 66 patients (30%) of which 9 (14%) were extracranial; 27 (41%) underwent thrombectomy with onset to puncture time averaging 141±90 min (median 112 (IQR 90-139) min) with full emergency department (ED) bypass. No imaging needed to be repeated for image quality; all patients were triaged correctly with no inter-hospital transfer required.

CONCLUSIONS

MSU use of advanced imaging including multiphasic head/neck CTA is feasible, offers high LVO yield and enables full ED bypass.

Improving Outcomes After Stroke: From Stroke Units to Mobile Stroke Units

A proactive clinical approach to stroke care improved functional outcomes with implementation of specialized in-hospital stroke units, urgently delivered systemic thrombolysis, mechanical thrombectomy and most recently with mobile stroke units deployed in the field. An 18% absolute difference in outcomes as a shift across all modified Rankin Scale strata at 3 months in the recent Berlin study may not be explained by just 8.8% more patients treated within the golden hour for thrombolytic treatment from symptom onset. These findings parallel the findings in the largest controlled multi-center BEST-MSU trial (Benefits of Stroke Treatment Delivered Using a Mobile Stroke Unit) to date. A shortcoming in blinding of the investigators to the mode of transportation is similar to blinding to the endovascular treatment in PROBE (Prospective Randomized Open, Blinded End-Point) design used in thrombectomy trials. A faster access to stroke experts and brain imaging in the field for all patients suspect of stroke regardless symptom nature, severity, duration or resolution delivered by mobile stroke units is likely the reason for improved outcomes akin the impact observed in the initial multidisciplinary approach to in-hospital stroke units and reperfusion therapies delivery.

Changes in Stroke Hospital Care During the COVID-19 Pandemic: A Systematic Review and Meta-Analysis

BACKGROUND AND PURPOSE

We systematically evaluated the impact of the coronavirus 2019 (COVID-19) pandemic on stroke care across the world.

METHODS

Observational studies comparing characteristics, acute treatment delivery, or hospitalization outcomes between patients with stroke admitted during the COVID-19 pandemic and those admitted before the pandemic were identified by Medline, Scopus, and Embase databases search. Random-effects meta-analyses were conducted for all outcomes.

RESULTS

We identified 46 studies including 129 491 patients. Patients admitted with stroke during the COVID-19 pandemic were found to be younger (mean difference, -1.19 [95% CI, -2.05 to -0.32]; I²=70%) and more frequently male (odds ratio, 1.11 [95% CI, 1.01-1.22]; I²=54%) compared with patients admitted with stroke in the prepandemic era. Patients admitted with stroke during the COVID-19 pandemic, also, had higher baseline National Institutes of Health Stroke Scale scores (mean difference, 0.55 [95% CI, 0.12-0.98]; I²=90%), higher probability for large vessel occlusion presence (odds ratio, 1.63 [95% CI, 1.07-2.48]; I²=49%) and higher risk for in-hospital mortality (odds ratio, 1.26 [95% CI, 1.05-1.52]; I²=55%). Patients with acute ischemic stroke admitted during the COVID-19 pandemic had higher probability of receiving endovascular thrombectomy treatment (odds ratio, 1.24 [95% CI, 1.05-1.47]; I²=40%). No difference in the rates of intravenous thrombolysis administration or difference in time metrics regarding onset to treatment time for intravenous thrombolysis and onset to groin puncture time for endovascular thrombectomy were detected.

CONCLUSIONS

The present systematic review and meta-analysis indicates an increased prevalence of younger patients, more severe strokes attributed to large vessel occlusion, and higher endovascular treatment rates during the COVID-19 pandemic. Patients admitted with stroke during the COVID-19 pandemic had higher in-hospital mortality. These findings need to be interpreted with caution in view of discrepant reports and heterogeneity being present across studies.

Prevalence, Characteristics, and Outcomes of Undetermined Intracerebral Hemorrhage: A Systematic Review and Meta-Analysis

BACKGROUND AND PURPOSE

There are scarce data regarding the prevalence, characteristics and outcomes of intracerebral hemorrhage (ICH) of undetermined (unknown or cryptogenic) etiology. We sought to determine the prevalence, radiological characteristics, and clinical outcomes of undetermined ICH.

METHODS

Systematic review and meta-analysis of studies involving patients with spontaneous ICH was conducted to primarily assess the prevalence and clinical-radiological characteristics of undetermined ICH. Additionally, we assessed the rates for ICH secondary to hypertensive arteriopathy and cerebral amyloid angiopathy. Subgroup analyses were performed based on the use of (1) etiology-oriented ICH classification, (2) detailed neuroimaging, and (3) Boston criteria among patients with cerebral amyloid angiopathy related ICH. We pooled the prevalence rates using random-effects models, and assessed the heterogeneity using Cochran Q and I² statistics.

RESULTS

We identified 24 studies comprising 15 828 spontaneous ICH patients (mean age, 64.8 years; men, 60.8%). The pooled prevalences of hypertensive arteriopathy ICH, undetermined ICH, and cerebral amyloid angiopathy ICH were 50% (95% CI, 43%-58%), 18% (95% CI, 13%-23%), and 12% (95% CI, 7%-17% [P<0.001 between subgroups]). The volume of ICH was the largest in cerebral amyloid angiopathy ICH (24.7 [95% CI, 19.7-29.8] mL), followed by hypertensive arteriopathy ICH (16.2 [95% CI, 10.9-21.5] mL) and undetermined ICH (15.4 [95% CI, 6.2-24.5] mL). Among patients with undetermined ICH, the rates of short-term mortality (within 3 months) and concomitant intraventricular hemorrhage were 33% (95% CI, 25%-42%) and 38% (95% CI, 28%-48%), respectively. Subgroup analysis demonstrated a higher rate of undetermined ICH among studies that did not use an etiology-oriented classification (22% [95% CI, 15%-29%]). No difference was observed between studies based on the completion of detailed neuroimaging to assess the rates of undetermined ICH (P=0.62).

CONCLUSIONS

The etiology of spontaneous ICH remains unknown or cryptogenic among 1 in 7 patients in studies using etiology-oriented classification and among 1 in 4 patients in studies that avoid using etiology-oriented classification. The short-term mortality in undetermined ICH is high despite the relatively small ICH volume.

Direct to Angiography vs Repeated Imaging Approaches in Transferred Patients Undergoing Endovascular Thrombectomy

Importance

A direct to angiography (DTA) treatment paradigm without repeated imaging for transferred patients with large vessel occlusion (LVO) may reduce time to endovascular thrombectomy (EVT). Whether DTA is safe and associated with better outcomes in the late (>6 hours) window is unknown. Also, DTA feasibility and effectiveness in reducing time to EVT during on-call vs regular-work hours and the association of interfacility transfer times with DTA outcomes have not been established.

Objective

To evaluate the functional and safety outcomes of DTA vs repeated imaging in the different treatment windows and on-call hours vs regular hours.

Design, Setting, and Participants

This pooled retrospective cohort study at 6 US and European comprehensive stroke centers enrolled adults (aged ≥18 years) with anterior circulation LVO (internal cerebral artery or middle cerebral artery subdivisions M1/M2) and transferred for EVT within 24 hours of the last-known-well time from January 1, 2014, to February 29, 2020.

Exposures

Repeated imaging (computed tomography with or without computed tomographic angiography or computed tomography perfusion) before EVT vs DTA.

Main Outcomes and Measures

Functional independence (90-day modified Rankin Scale score, 0-2) was the primary outcome. Symptomatic intracerebral hemorrhage, mortality, and time metrics were also compared between the DTA and repeated imaging groups.

Results

A total of 1140 patients with LVO received EVT after transfer, including 327 (28.7%) in the DTA group and 813 (71.3%) in the repeated imaging group. The median age was 69 (interquartile range [IQR], 59-78) years; 529 were female (46.4%) and 609 (53.4%) were male. Patients undergoing DTA had greater use of intravenous alteplase (200 of 327 [61.2%] vs 412 of 808 [51.0%]; P = .002), but otherwise groups were similar. Median time from EVT center arrival to groin puncture was faster with DTA (34 [IQR, 20-62] vs 60 [IQR, 37-95] minutes; P < .001), overall and in both regular and on-call hours. Three-month functional independence was higher with DTA overall (164 of 312 [52.6%] vs 282 of 763 [37.0%]; adjusted odds ratio [aOR], 1.85 [95% CI, 1.33-2.57]; P < .001) and during regular (77 of 143 [53.8%] vs 118 of 292 [40.4%]; P = .008) and on-call (87 of 169 [51.5%] vs 164 of 471 [34.8%]; P < .001) hours. The results did not vary by time window (0-6 vs >6 to 24 hours; P = .88 for interaction). Three-month mortality was lower with DTA (53 of 312 [17.0%] vs 186 of 763 [24.4%]; P = .008). A 10-minute increase in EVT-center arrival to groin puncture in the repeated imaging group correlated with 5% reduction in the functional independence odds (aOR, 0.95 [95% CI, 0.91-0.99]; P = .01). The rates of modified Rankin Scale score of 0 to 2 decreased with interfacility transfer times of greater than 3 hours in the DTA group (96 of 161 [59.6%] vs 15 of 42 [35.7%]; P = .006), but not in the repeated imaging group (75 of 208 [36.1%] vs 71 of 192 [37.0%]; P = .85).

Conclusions and Relevance

The DTA approach may be associated with faster treatment and better functional outcomes during all hours and treatment windows, and repeated imaging may be reasonable with prolonged transfer times. Optimal EVT workflow in transfers may be associated with faster, safe reperfusion with improved outcomes.

Utility of Intravenous Alteplase Prior to Endovascular Stroke Treatment: A Systematic Review and Meta-analysis of RCTs

OBJECTIVE

To provide a critical appraisal on the evidence from randomized controlled clinical trials (RCTs) on the utility of direct endovascular treatment (dEVT) compared to the combination of endovascular treatment preceded by IV thrombolysis (bridging therapy [BT]) for patients with acute large vessel occlusion (LVO).

METHODS

Eligible RCTs were identified by searching Medline and Scopus. We calculated the corresponding odds ratios (ORs) and 95% confidence intervals (CIs) and pooled estimates using random-effects models. The primary outcome was the probability of modified Rankin scale (mRS) score of 0 to 2 at 3 months.

RESULTS

We included 3 studies comprising 1,092 patients. No difference between the dEVT and BT groups was detected for the outcomes of mRS score of 0 to 2 (OR 1.08, 95% CI 0.85-1.38; adjusted OR 1.11, 95% CI 0.76-1.63), mRS score of 0 to 1 (OR 1.10, 95% CI 0.84-1.43; adjusted OR 1.16, 95% CI 0.84-1.61), and functional improvement at 3 months (common OR 1.08, 95% CI 0.88-1.34; adjusted common OR 1.09, 95% CI 0.86-1.37). Patients receiving dEVT had significantly lower likelihood of successful recanalization before the endovascular procedure compared to those receiving BT (OR 0.37, 95% CI 0.18-0.77). Patients receiving dEVT had lower intracranial bleeding rates compared to those receiving BT (OR 0.67, 95% CI 0.49-0.92) but without a significant difference in the probability of symptomatic intracranial hemorrhage. No differences in all-cause mortality, serious adverse events, or procedural complications between the 2 groups were uncovered.

CONCLUSIONS

We detected no differences in functional outcomes of IV thrombolysis-eligible patients with an acute LVO receiving dEVT compared to BT. Because uncertainty for most endpoints remains large and the available data are not able to exclude the possibility of overall benefit or harm, further RCTs are needed.

Criteria for Emergency Brain MRI During Stroke-Alert

OBJECTIVES

Intravenous (IV) tissue plasminogen activator (tPA) should be given to patients with acute ischemic stroke (AIS) and avoided in stroke mimics (SM). Select use of emergency brain magnetic resonance imaging (eMRI-brain) in stroke-alerts aids diagnosis, but accepted utilization criteria for eMRI-brain do not currently exist. We developed criteria for eMRI-brain and report the yield of eMRI-brain in stroke-alert patients.

MATERIALS AND METHODS

We developed three history-based criteria for performing eMRI-brain during stroke-alerts: (1) history of previous similar deficits, (2) change in consciousness at onset of symptoms, (3) symptom presentation consistent with migraine aura. We then performed a retrospective chart review of patients who presented as a stroke-alert over a 5-year period and determined how these criteria affected administration of IV tPA to AIS and SM patients.

RESULTS

Among 3,512 stroke-alerts, 230 (8.1%) patients met our criteria for eMRI-brain exams: 217 (92.6%) had SM and 17 (7.4%) had AIS. Our IV tPA decision-making analysis showed that based on eMRI-brain IV tPA was less frequently administered to SM patients (PCC-0.841, p=0.036) with less failures to administer IV tPA to patients with AIS (PCC -0.907, p-value=0.013, Pearson correlation coefficient). No patients became ineligible for IV tPA due to MRI-related time delays.

CONCLUSIONS

Our history based criteria for performing eMRI-brain during stroke-alerts show a high yield of stroke mimics. Selective eMRI-brain improves decision-making accuracy regarding IV tPA administration.

Novel robotic TCD ultrasound with bubbles versus standard care to detect right to left shunt: Study methods

BACKGROUND AND PURPOSE

Right to left shunt (RLS), from patent foramen ovale (PFO) or elsewhere, is a recognized risk factor for stroke. Current standard of care for RLS diagnosis includes transthoracic echocardiography (TTE) which is insensitive, transesophageal echocardiography (TEE) which is invasive, and transcranial Doppler (TCD) which has excellent sensitivity and specificity for RLS but is heavily operator dependent and expertise is scarce. The purpose of this study was to evaluate the RLS detection rate of a novel robotic-assisted TCD (ra-TCD) to standard of care diagnostic techniques, including TTE, TEE, and TCD.

METHODS

This is a multicenter, prospective, single-arm, nonsignificant risk device study of ra-TCD versus TTE for RLS diagnosis in adult patients who present with neurological signs and symptoms that include embolic stroke or transient ischemic attack on the differential diagnosis. Up to 150 subjects will be enrolled at up to seven centers considering the prevalence of PFO, suboptimal transtemporal windows, and potential dropouts. Enrolled patients will undergo ra-TCD supine and at 45° in a manner otherwise in line with standard of care TCD bubble technique. The enrolled patients will have undergone TTE, and optionally standard TCD and TEE, per usual care.

RESULTS

The primary efficacy endpoint is percent detection of RLS by ra-TCD compared against TTE. The primary safety endpoint is the incidence of device-related serious adverse events.

CONCLUSIONS

This is the first multicenter, prospective study evaluating the accuracy, feasibility, and safety of novel ra-TCD for the diagnosis of RLS as compared to standard of care diagnostics.

A cost-effective plan for global testing - an infection rate stratified, algorithm guided, multiple-level, continuously pooled testing strategy

The most effective measure to prevent or stop the spread of infectious diseases is the early identification and isolation of infected individuals through comprehensive screening. At present, in the COVID-19 pandemic, such screening is often limited to isolated regions as determined by local governments. Screening of potentially infectious individuals should be conducted through coordinated national or global unified actions. Our current research focuses on using resources to conduct comprehensive national and regional regular testing with a risk rate based, algorithmic guided, multiple-level, pooled testing strategy. Here, combining methodologies with mathematical logistic models, we present an analytic procedure of an overall plan for coordinating state, national, or global testing. The proposed plan includes three parts 1) organization, resource allocation, and distribution; 2) screening based on different risk levels and business types; and 3) algorithm guided, multiple level, continuously screening the entire population in a region. This strategy will overcome the false positive and negative results in the polymerase chain reaction (PCR) test and missing samples during initial tests. Based on our proposed protocol, the population screening of 300,000,000 in the US can be done weekly with between 15,000,000 and 6,000,000 test kits. The strategy can be used for population screening for current COVID-19 and any future severe infectious disease when drugs or vaccines are not available.

Autotitrating Bilevel Positive Airway Pressure in Large Vessel Steno-Occlusive Stroke Patients With Suspected Sleep Apnea: A Multicenter Randomized Controlled Study

Background: We hypothesized that autotitrating bilevel positive airway pressure (auto-BPAP) favorably affects short-term clinical outcomes in hyperacute ischemic stroke.

Methods: In a multicenter, randomized, controlled trial patients with large vessel steno-occlusive stroke and clinically suspected sleep apnea were allocated to auto-BPAP or standard stroke care alone. Auto-BPAP was initiated within 24 h from stroke onset and performed over 48 h during diurnal and nocturnal sleep. Sleep apnea was assessed using cardiorespiratory polygraphy. Primary endpoint was early neurological improvement on National Institutes of Health Stroke Scale (NIHSS) score at 72 h. Safety and tolerability of BPAP, functional independence [modified Rankin Scale (mRS) 0–2], stroke recurrence, and mortality at 90 days were assessed.

Results: Due to low recruitment, the trial was prematurely stopped after 24 patients had been randomized (auto-BPAP, n = 14; control, n = 10): median baseline NIHSS 13 (5.5–18), 88% large vessel occlusion, and 12% large vessel stenosis. Polygraphy confirmed sleep apnea in 64% of auto-BPAP and 88% of control patients (p = 0.34). Adherence to auto-BPAP was achieved by 9 of the 14 (64%) patients. Between auto-BPAP and control patients, no differences were observed in early neurological improvement (median NIHSS change: −2.0, IQR = 7 points vs. −0.5, IQR = 3 points), 90 days functional independence (21 vs. 30%, p = 0.67), stroke recurrence (0 vs. 20%, p = 0.16), and death (14 vs. 20%, p = 1.0). No safety concerns were identified.

Conclusions: In this prematurely terminated trial, auto-BPAP was safe but did not show an effect on short-term clinical outcomes in selected ischemic stroke patients. Its tolerability, however, may be limited in hyperacute stroke care and needs to be improved before larger trials are conducted.

Clinical Trial Registration:ClinicalTrials.gov, identifier: NCT01812993.

Abstract P856: Contributors to Internal Primary Stroke Center Transfer Delays: Factors Beyond Stroke Coordinators’ Control

Background: Stroke coordinators often are challenged to transfer patients to higher levels of care, facing internal system, transport, and comprehensive stroke center (CSC) factors that may slow the transfer process. We aimed to understand the internal challenges faced by stroke coordinators at primary stroke centers/acute stroke ready hospitals (PSC/ASRH) in the transfer process.

Methods: Six national focus groups with PSC/ASRH staff experienced with stroke transfers were conducted by web conference. Interviews were conducted using pre-scripted open-ended questions; information was recorded and data were transcribed for theme identification.

Results: Participants were from Northeast, Mid-Atlantic, Southeast, Midwest, and West Coast USA. Internal PSC/ASRH problems were tied exclusively to physicians: Emergency department (ED) physicians’ lack knowledge of how/when to order advanced imaging; delays initiating telemedicine guidance were common; and, negative attitudes towards stroke emergencies among “tenured” ED physicians were identified. All participants noted that they were compliant with door-to-noncontrast CT and alteplase treatment time metrics, however, radiologists commonly used the full 2-hours allotted for CTA and CTP reads, and many telemedicine neurologists refused to review/interpret advanced imaging choosing to rely on the local general radiologists’ formal interpretation.

Conclusions: Major factors contributing to internal PSC/ASRH transfer delays are exclusively physician-based. Physician education, standardized algorithms for advanced imaging selection, more-timely regulatory metrics for advanced imaging interpretation, and improved telemedicine physician expertise and guidance would improve transfer timeliness in these centers.

Abstract P525: Endovascular Thrombectomy Outcomes in Transferred Octogenarians: A Multicenter Pooled Analysis

Background: Acute ischemic strokes outcomes may be less favorable in elderly patients. Whether transferring octogenarians with large vessel occlusion (LVO) for endovascular thrombectomy (EVT) results in similar outcomes to younger patients is uncertain.

Methods: A pooled cohort from 6 centers (Europe, US) from 1/2014 to 5/2020 of pts with (ICA, M1, M2) LVO transferred for EVT ≤ 24 hrs from LKW. Patients were stratified into < 80 vs ≥ 80 years old. We compared 90 day functional independence and safety outcomes and assessed for predictors of good outcome (mRS 0-2) and profound disability (mRS 5-6).

Results: Of 1176 pts received EVT as transfers, 216 (18%) were octogenarians. Baseline NIHSS was higher in octogenarians [19 (14, 22) vs 17 (12, 21), p<0.001], while IV tPA (52% vs 54%, p=0.52) and time LKW to EVT center [285 (193, 537) vs 272 (190, 470) min, p=0.15] were similar. Functional independence rates were lower in patients ≥ 80 as compared to < 80 (26% vs 46%, aOR 0.50, 95%CI 0.34-0.75, p=0.001). sICH was similar (8.6 vs 9.9%, p=0.56), but octogenarians had significantly higher 90-day mortality (42% vs 17%, p<0.001).

Milder strokes (aOR 0.88, 95%CI 0.86-0.91, p<0.001), earlier presentation (aOR 0.95, 95%CI 0.91-0.98, p=0.004) and IV tPA (aOR 1.34, 95%CI 0.98-1.84, p=0.069) were associated with higher functional independence odds after EVT in octogenarians. Higher stroke severity (12% for each point, aOR=1.12, 95%CI 1.11-1.17-, p<0.001) and delayed reperfusion (3% for each additional hr, aOR 1.03, 95%CI 1.00-1.06, p=0.071) were associated with profound disability following EVT in octogenarians.

Conclusion: EVT may be associated with lower independence rates in transferred octogenarians with LVO. Milder stroke severity, earlier presentation and IV thrombolysis increased the odds of good outcomes in octogenarians. Severe strokes and later treatment were associated with profound disability. Optimized selection and workflow is warranted in transferring elderly patients for EVT.

Abstract MP5: Intravenous Thrombolysis With Tenecteplase in Patients With Large Vessel Occlusions: Systematic Review and Meta-Analysis

Background: Accumulating evidence from randomized-controlled clinical trials (RCTs) suggest that tenecteplase may represent an effective treatment alternative to alteplase for acute ischemic stroke (AIS). In the present systematic review and meta-analysis we sought to compare the efficacy and safety outcomes of intravenous tenecteplase to intravenous alteplase administration for AIS patients with large vessel occlusions (LVO).

Methods: We searched MEDLINE and Scopus for published RCTs providing outcomes of AIS with confirmed LVO receiving intravenous thrombolysis with either tenecteplase at different doses or alteplase at standard dose 0.9mg/kg. The primary outcome was the odds of modified Rankin Scale (mRS) score of 0-2 at 3 months.

Results: We included 4 RCTs including a total of 433 patients. Patients with confirmed LVO receiving tenecteplase had higher odds of successful recanalization (OR=3.05, 95%CI: 1.73-5.40; Figure A), mRS scores of 0-2 [odds ratio (OR)=2.06, 95%CI: 1.15-3.69; Figure B], and functional improvement defined as 1-point decrease across all mRS grades (common OR=1.84, 95%CI: 1.18-2.87; Figure C) at 3 months compared to patients with confirmed LVO receiving alteplase. There was little or no heterogeneity between the results provided from included studies regarding the aforementioned outcomes (I 2 ≤20%). No difference in the outcomes of early neurological improvement, symptomatic intracranial hemorrhage (ICH), any ICH and the rates of mRS 0-1 or all-cause mortality at 3 months were detected between patients with LVO receiving intravenous thrombolysis with either tenecteplase or alteplase.

Conclusion: AIS patients with LVO receiving intravenous thrombolysis with tenecteplase have significantly better recanalization and clinical outcomes compared to patients receiving intravenous alteplase.

Abstract P463: Direct to Angio in Transferred Patients is Associated With Faster Reperfusion and Higher Functional Independence Rates Both During Regular and On-Call Hours: A Multi Center Cohort

Background: Direct To Angio (DTA) for transferred large vessel occlusions (LVO) lowers time to endovascular thrombectomy (EVT), reperfusion and potentially improves outcomes. Safety and efficacy of DTA in late time window and on-call hours is unknown.

Methods: Pooled cohort from 6 centers (EU, US) from 1/14-5/20 (ICA, M1, M2) LVO pts transferred for EVT≤24 hrs from LKW. Pts stratified into with repeat imaging (RI) (CT+/- CTA/CTP) and without RI (DTA). We compared time metrics, good outcome (90 day mRS 0-2), safety (sICH, mortality) and assessed the impact of arrival for EVT; regular (M-F, 8am-5pm) vs on-call hrs. Propensity matched analysis was done.

Results: Of 1178 EVT transfers, 334 (28%) were DTA. DTA pts had more tPA (61% vs 51%, p=0.002), trended to lower NIHSS 17 (12, 20) vs 17 (13, 21), p=0.07 and lower LKW to arrival 268 (190, 430) min vs 280 (190, 518), p=0.097. Groin puncture (GP) was faster with DTA (p<0.001) Fig 1. Good outcomes were higher with DTA overall (53% vs 38%, aOR 1.7, 95%CI 1.3-2.4, p=0.001), regular (54% vs 41%, p=0.07) and on-call hrs (52% vs 36%, p=0.008), mortality was lower overall (17% vs 24%, p=0.04) and all hrs Fig 2 A-C. sICH rates were similar. A 10 min increase arrival to GP with RI correlated to 5% reduction in good outcome odds (aOR 0.95, 95%CI 0.91-0.99, p=0.01). The results did not vary by time window (0-6 hrs vs >6-24, p=0.88 for interaction). In propensity matched 75 pairs, DTA had shorter time to EVT (19 min vs 52, p<0.001) and higher mRS 0-2 (55% vs 32%, aOR 4.8 (1.9-12.4), p=0.001) fig 2D. However, the probability of mRS 0-2 decreased with increasing transfer times in DTA pts (< 3 hrs 59% vs 36% ≥ 3 hrs, p<0.001) but not in RI (36% vs 37%, p=0.88) fig 3.

Conclusion: In pooled, non-randomized data DTA may result in faster treatment, safe and better functional outcomes, during all hours and treatment windows. Repeat imaging may be reasonable with prolonged transfer times. Optimal EVT workflow in transfers may result in faster, safe reperfusion with higher good outcomes.

Abstract P166: The Primary Stroke Center Transfer Experience to Higher Levels of Care: A Qualitative Study

Background: Transfer times from primary stroke centers/acute stroke ready hospitals (PSCs/ASRHs) to higher levels of care have been shown to be excessive in many cases, promoting some to believe that bypass regulations should be instituted. Yet barriers to rapid transfer remain undescribed in the literature. The purpose of this work is to investigate these issues and the locus of control for transfer time delays.

Methods: Six national focus groups with PSC/ASRH staff experienced with stroke transfers were conducted by web conference. Interviews were conducted using pre-scripted open-ended questions; information was recorded, and data were transcribed, for theme identification.

Results: Participants were from Northeast, Mid-Atlantic, Southeast, Midwest, and West Coast USA. Data were grouped into 3 main categories representing where transfer problems initiated. Themes emerging within the Internal PSC/ASRH Category were exclusively emergency department (ED) physician focused including knowing how/when to use advanced imaging and telemedicine resources. Of note, all participants were compliant with door-to-CT and treatment time metrics. Within the Transport Category , themes included inadequate time-to-response by ground and air ambulances, and specialty transport costs. Within the Internal Comprehensive Stroke Center (CSC) Category , themes included complex communication, overwhelmed systems, and poor guidance on patient selection.

Conclusions: While ED physician contributors to transfer delays are within the control of PSCs/ASRHs, more challenging factors to rapid transfer include factors within transport systems and CSCs themselves. Quantification of these factors is warranted to support transfer system redesign with rapid access to care.

Abstract P82: The Impact of SARS-COV-2 on Stroke Epidemiology and Care: A Meta-Analysis

Background: Emerging data indicates an increased risk for cerebrovascular events with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus and highlights the potential impact of coronavirus disease (COVID-19) on the management and outcomes of acute stroke. We conducted a systematic review and meta-analysis to evaluate the aforementioned considerations.

Methods: We performed a meta-analysis of observational cohort studies reporting on the occurrence and/or outcomes of patients with cerebrovascular events in association with their SARS-CoV-2 infection status. We used a random-effects model. Summary estimates were reported as odds ratios (ORs) and corresponding 95% confidence intervals (95%CI).

Results: We identified 16 cohort studies including 44,004 patients. Among patients with SARS-CoV-2, 1.3% (95%CI: 0.9-1.8%; I 2 =88%) were hospitalized for cerebrovascular events, 1.2% (95%CI: 0.8-1.5%; I 2 =85%) for ischemic stroke, and 0.2% (95%CI: 0.1-0.4%; I 2 =69%) for hemorrhagic stroke. Compared to non-infected contemporary or historical controls, patients with SARS-CoV-2 infection had increased odds of ischemic stroke (OR=3.58, 95%CI: 1.43-8.92; I 2 =43%) and cryptogenic stroke (OR=3.98, 95%CI: 1.62-9.77; I 2 =0%). Odds for in-hospital mortality were higher among SARS-CoV-2 stroke patients compared to non-infected contemporary or historical stroke patients (OR=5.60, 95%CI: 3.19-9.80; I 2 =45%). SARS-CoV-2 infection status was not associated to the likelihood of receiving intravenous thrombolysis (OR=1.42, 95%CI: 0.65-3.10; I 2 =0%) or endovascular thrombectomy (OR=0.78, 95%CI: 0.35-1.74; I 2 =0%) among hospitalized ischemic stroke patients during the COVID-19 pandemic. Diabetes mellitus was found to be more prevalent among SARS-CoV-2 stroke patients compared to non-infected contemporary or historical controls (OR=1.39, 95%CI: 1.04-1.86; I 2 =0%).

Conclusion: SARS-CoV-2 appears to be associated with an increased risk of ischemic stroke, particularly the cryptogenic subtype. SARS-CoV-2 infection in stroke substantially increases the mortality risk.

Abstract P411: Prevalence, Characteristics and Outcomes of Undetermined Intracerebral Hemorrhage: A Systematic Review and Meta-Analysis

Objective: We sought to determine the prevalence, radiological characteristics, and clinical outcomes of intracerebral hemorrhage (ICH) of undetermined etiology.

Methods: Systematic review and meta-analysis of studies involving patients with spontaneous ICH was conducted to assess the prevalence and clinical-radiological characteristics of undetermined ICH. Additionally, we assessed the rates for ICH secondary to hypertensive arteriopathy (HTN-A) and cerebral amyloid angiopathy (CAA). Subgroup analyses were performed based on the use of a) etiology-oriented ICH classification, b) detailed neuroimaging, and c) Boston criteria among CAA-ICH.

Results: 24 studies were included (n=15,828; mean age: 64.8 years, males: 60.8%). The pooled prevalence of HTN-A ICH, undetermined ICH and CAA-ICH were 50% (95%CI: 43-58%), 18% (95%CI: 13-23%), and 12% (95%CI: 7-17%; p<0.001 between subgroups). The volume of ICH was largest in CAA-ICH 24.7mL (95%CI: 19.7-29.8mL), followed by HTN-A ICH 16.2mL (95%CI: 10.9-21.5mL) and undetermined ICH 15.4mL (95%CI: 6.2-24.5mL). Among patients with undetermined ICH, the rates of short-term mortality and intraventricular hemorrhage were 33% (95%CI: 25-42%) and 38% (95%CI: 28-48%), respectively. Subgroup analysis demonstrated a higher rate of undetermined ICH among studies that did not use an etiology-oriented classification (22%; 95%CI: 15-29%). No difference was observed between studies based on the completion of detailed neuroimaging to assess the rates of undetermined ICH (p=0.62).

Conclusions: The etiology of spontaneous ICH remains undetermined among one in five patients in studies using etiology-oriented classification and among one in four patients in studies that avoid using etiology-oriented classification. The short-term mortality in undetermined ICH is high despite the relatively small ICH volume. Our findings suggest the use of etiology-oriented classification to approach ICH patients (Figure).

Abstract P17: Outcomes After Thrombolysis for Ischemic Stroke in Costa Rica Compare Favorably With International Cohorts

Background: More than 70% of strokes occur in resource-poor countries. Outcomes are often not well documented. rt-PA for acute ischemic stroke was approved in 2012 for use in Costa Rica (CR). A hub and spoke model was initiated and a dataset established, the CR Stroke Registry Program (CRSRP) for conditional- and post-approval monitoring. Here, we compared CRSRP rt-PA outcomes to similarly treated subjects from the 1995 NINDS rt-PA trial and the 2019 CLOTBUST-ER control arm.

Methods: Subjects were matched using a published pairing methodology and day 7-10/discharge modified Rankin Score (mRS), symptomatic intracerebral hemorrhages (SICH) and early mortality compared. A mortality model was generated from 15 randomized controlled trials (RCTs) and outcomes compared at similar baselines. SICH rates were compared with other cohorts: Get With The Guidelines (GWTG), a combined international IV thrombolysis trial pool, and 2 Ibero-American populations.

Results: Of 424 CRSRP patients, 284 receiving rt-PA under 3 hrs were matched with 308 NINDS subjects. 131 non-diabetic CRSRP subjects, treated within 4.5 hrs, NIHSS 10 - 24 and Alberta Stroke Program Early CT Score (ASPECTS)>7, were matched with 300 CLOTBUST-ER subjects. Percent achieving either mRS 0-1 or 0-2 did not differ between CRSRP and either NINDS or CLOTBUST-ER (mRS 0-1: CRSRP:33.9% vs NINDS:33.6%; CRSRP:23.8% vs CLOTBUST-ER:27.0%, all p>=.05 / mRS 0-2: CRSRP:40.0% vs NINDS:41.4%; CRSRP:31.1% vs CLOTBUST-ER:36.1%, all p=>.05). Mortality was higher for CRSRP vs CLOTBUST-ER (6.6% vs 0.8%; p=0.05) but not vs NINDS (6.8% vs 4.3%; p=0.3). A predictive model (R 2 =0.39) showed neither cohort exceeded expected pooled mortality, with CLOTBUST-ER the lowest mortality. SICH rate was higher in CRSRP vs CLOTBUST-ER (7.3% vs 0.0% p=0.008) but not vs NINDS (5.7% vs 6.8% p=0.7)). SICH rates were not higher when compared with 4 international cohorts.

Conclusion: Functional outcomes of Costa Rican patients receiving rt-PA compared favorably with 2 RCTs (NINDS and CLOTBUST-ER). SICH and mortality were higher than CLOTBUST-ER, although both were within expected range compared to other international cohorts. Systems of care development in order to further lower SICH and participate in the endovascular era are underway.