Prestroke Disability and Outcome After Thrombectomy for Emergent Anterior Circulation Large Vessel Occlusion Stroke

Utilization, Workflow, and Outcomes of Endovascular Thrombectomy in Patients With vs Without Premorbid Disability in a National Registry

Background and Objectives

Given the paucity of high-quality safety/efficacy data on acute stroke therapies in patients with premorbid disability, they risk being routinely excluded from such therapies. We examined utilization of endovascular thrombectomy (EVT), associated workflow, and poststroke outcomes among patients with vs without premorbid disability.

Methods

We used national registry data on thrombolysis/EVT for the Czech Republic from 1 January 2016 to 31 December 2020. Premorbid disability was defined as prestroke modified Rankin Scale score (mRS) ≥3. We compared proportions of patients with vs without premorbid disability who received EVT and examined workflow times. We compared ΔmRS-change in mRS from prestroke to 3 months-in patients with vs without premorbid disability, in addition to intracerebral hemorrhage (ICH), mortality, and discharge NIHSS (National Institutes of Health Stroke Scale score), adjusting for age, sex, baseline NIHSS, and comorbidities, and verified using propensity score weighting (PSW) and matching for differences in treatment assignment. We stratified by age group (<65, 65-74, 75-84, ≥85 years) to explore outcome heterogeneity with vs without premorbid disability.

Results

Among 22,405 patients with ischemic stroke who received thrombolysis/EVT/both, 1,712 (7.6%) had prestroke mRS ≥ 3. Patients with prestroke disability were less likely to receive EVT vs those without (10.1% vs 20.7%, aOR: 0.30, 95% CI 0.24-0.36). When treated, they had longer door-to-arterial puncture times (median: 75 minutes, IQR: 58-100 vs 54, IQR: 27-77, adjusted difference: 12.5, 95% CI 2.68-22.3). Patients with prestroke disability receiving thrombolysis/EVT/both had worse ΔmRS (adjusted rate ratio, aIRR on PSW: 1.57, 95% CI 1.43-1.72), rates of 3-month mRS 5-6, discharge NIHSS, and mortality (aOR-PSW [mortality]: 2.54, 95% CI 1.92-3.34), while ICH did not significantly differ. 32.1% of patients with prestroke disability receiving thrombolysis/EVT/both successfully returned to prestroke state, but this proportion ranged from 19.6% for those older than 85 years to 66.0% for those younger than 65 years. Regardless of premorbid disability, EVT was associated with better outcomes including lower ΔmRS (aIRR-PSW: 0.87, 95% CI 0.83-0.91) and mortality, with no interaction of treatment effect by premorbid disability status (e.g., mortality pinteraction = 0.73). EVT recipients with premorbid disability did not differ significantly for several outcomes including ΔmRS (aIRR: 0.99, 95% CI 0.84-1.17) but were more likely to have 3-month mRS 5-6 (70.1% vs 39.5% without premorbid disability, aOR: 1.85, 95% CI 1.12-3.04).

Discussion

Patients with premorbid disability were less likely to receive EVT, had slower treatment times, and had worse outcomes compared with patients without premorbid disability. However, regardless of premorbid disability, patients fared better with EVT vs medical management and one-third with prestroke disability returned to their prestroke status.

External validation of clinical risk prediction score for elderly treated with endovascular thrombectomy

BACKGROUND AND AIM

The thrombectomy in the elderly prediction score (TERPS) for functional outcome after anterior circulation endovascular therapy (EVT) in patients ≥ 80 years was recently developed. The aim of this study was to assess predictors of functional outcome in the elderly and validate the prediction model.

METHODS

Consecutive patients treated with EVT from the Oslo Acute Reperfusion Stroke Study were evaluated for inclusion. Clinical and radiological parameters were used to calculate the TERPS, and functional outcome were assessed at 3-month follow-up.

RESULTS

Out of 1028 patients who underwent EVT for acute ischemic stroke from January 2017 to July 2022, 218 (21.2%) patients ≥ 80 years with anterior ischemic stroke were included. Fair outcome, defined as modified Rankin scale ≤ 3 (mRS), was achieved in 117 (53.7%). In bivariate analyses, male sex (p 0.035), age (p 0.025), baseline National Institute of Health Stroke Scale (NIHSS, p < 0.001), pre-stroke mRS (p 0.002) and Alberta Stroke Program Early Computed Tomography score (ASPECTS, p 0.001) were associated with fair outcome. Significant predictors for fair outcome in regression analyses were lower pre-stroke mRS, adjusted odd ratio, (aOR) 0.67 (95% CI 0.50-0.91, p 0.01), NIHSS, aOR 0.92 (95% CI 0.87-0.97, p 0.002), and higher ASPECTS, aOR 1.22 (95% CI 1.03-1.44, p 0.023). The area under the curve (AUC) using TERPS was 0.74 (95% CI 0.67-0.80).

CONCLUSIONS

The risk prediction score TERPS showed moderate performance in this external validation. Other variables may still be included to improve the model and validation using other cohorts is recommended.

TRIAL REGISTRATION

NCT06220981.

CLEAR Thrombectomy Score: An Index to Estimate the Probability of Good Functional Outcome With or Without Endovascular Treatment in the Late Window for Anterior Circulation Occlusion

BACKGROUND

With the expanding eligibility for endovascular therapy (EVT) of patients presenting in the late window (6-24 hours after last known well), we aimed to derive a score to predict favorable outcomes associated with EVT versus best medical management.

METHODS AND RESULTS

A multinational observational cohort of patients from the CLEAR (Computed Tomography for Late Endovascular Reperfusion) study with proximal intracranial occlusion (2014-2022) was queried (n=58 sites). Logistic regression analyses were used to derive a 9-point score for predicting good functional outcome (modified Rankin Scale score 0-2 or return to premorbid modified Rankin Scale score) at 90 days, with sensitivity analyses for prespecified subgroups conducted using bootstrapped random forest regressions. Secondary outcomes included 90-day functional independence (modified Rankin Scale score 0-2), poor outcome (modified Rankin Scale score 5-6), and 90-day survival. The score was externally validated with a single-center cohort (2014-2023). Of the 3231 included patients (n=2499 EVT), a 9-point score included age, early computed tomography ischemic changes, and stroke severity, with higher points indicating a higher probability of a good functional outcome. The areas under the curve for the primary outcome among EVT and best medical management subgroups were 0.72 (95% CI, 0.70-0.74) and 0.87 (95% CI, 0.84-0.90), respectively, with similar performance in the external validation cohort (area under the curve, 0.71 [95% CI, 0.66-0.76]). There was a significant interaction between the score and EVT for good functional outcome, functional independence, and poor outcome (all Pinteraction<0.001), with greater benefit favoring patients with lower and midrange scores.

CONCLUSIONS

This score is a pragmatic tool that can estimate the probability of a good outcome with EVT in the late window.

REGISTRATION

URL: https://www.Clinicaltrials.gov; Unique identifier: NCT04096248.

Outcomes and safety of endovascular treatment from 6 to 24 hours in patients with a pre-stroke moderate disability (mRS 3): a multicenter retrospective study

BACKGROUND

Approximately 30% of patients presenting with acute ischemic stroke (AIS) due to large vessel occlusion have pre-stroke modified Rankin Scale (mRS) scores ≥2. We aimed to investigate the safety and outcomes of endovascular treatment (EVT) in patients with AIS with moderate pre-stroke disability (mRS score 3) in an extended time frame (ie, 6-24 hours from the last time known well).

METHODS

Data were collected from five centers in Europe and the USA from January 2018 to January 2023 and included 180 patients who underwent EVT in an extended time frame. Patients were divided into two groups of 90 each (Group 1: pre-mRS 0-2; Group 2: pre-mRS 3; 71% women, mean age 80.3±11.9 years). Primary outcomes were: (1) 3-month good clinical outcome (Group 1: mRS 0-2, Group 2: mRS 0-3) and ΔmRS; (2) any hemorrhagic transformation (HT); and (3) symptomatic HT. Secondary outcomes were successful and complete recanalization after EVT and 3-month mortality.

RESULTS

No between-group differences were found in the 3-month good clinical outcome (26.6% vs 25.5%, P=0.974), any HT (26.6% vs 22%, P=0.733), and symptomatic HT (8.9 vs 4.4%, P=0.232). Unexpectedly, ΔmRS was significantly smaller in Group 2 compared with Group 1 (1.64±1.61 vs 2.97±1.69, P<0.001). No between-group differences were found in secondary outcomes.

CONCLUSION

Patients with pre-stroke mRS 3 are likely to have similar outcomes after EVT in the extended time frame to those with pre-stroke mRS 0-2, with no difference in safety.

Noncontrast CT Selected Thrombectomy vs Medical Management for Late-Window Anterior Large Vessel Occlusion

BACKGROUND AND OBJECTIVES

There is uncertainty whether patients with large vessel occlusion (LVO) presenting in the late 6-hour to 24-hour time window can be selected for endovascular therapy (EVT) by noncontrast CT (NCCT) and CT angiography (CTA) for LVO detection. We evaluated the clinical outcomes of patients selected for EVT by NCCT compared with those medically managed in the extended time window.

METHODS

This multinational cohort study was conducted at 66 sites across 10 countries. Consecutive patients with proximal anterior LVO stroke selected for EVT by NCCT or medically managed and presenting within 6-24 hours of time last seen well (TSLW) from January 2014 to May 2022 were included. The primary end point was the 90-day ordinal shift in the modified Rankin Scale (mRS) score. Inverse probability treatment weighting (IPTW) and multivariable methods were used.

RESULTS

Of 5,098 patients screened, 839 patients were included, with a median (interquartile range) age of 75 (64-83) years; 455 (54.2%) were women. There were 616 patients selected to undergo EVT by NCCT (73.4%) and 223 (26.6%) who were medically managed. In IPTW analyses, there was a more favorable 90-day ordinal mRS shift in patients selected by NCCT to EVT vs those who were medically managed (odds ratio [OR] 1.99, 95% CI 1.53-2.59; p < 0.001). There were higher rates of 90-day functional independence (mRS 0-2) in the EVT group (40.1% vs 18.4%, OR 3.31, 95% CI 2.11-5.20; p < 0.001). sICH was nonsignificantly higher in the EVT group (8.5% vs 1.4%, OR 3.77, 95% CI 0.72-19.7, p = 0.12). Mortality at 90 days was lower in the EVT vs MM group (23.9% vs 32.3%, OR 0.61, 95% CI 0.45-0.83, p = 0.002).

DISCUSSION

In patients with proximal anterior LVO in the extended time window, there was a lower rate of disability and mortality in patients selected with NCCT and CTA to EVT compared with those who were medically managed. These findings support the use of NCCT as a simpler and more inclusive approach to patient selection in the extended window.

TRIAL REGISTRATION INFORMATION

This study was registered at ClinicalTrials.gov under NCT04096248.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that for patients with proximal anterior circulation occlusion presenting with ischemic stroke from 6 to 24 hours, compared with medical management, those undergoing thrombectomy based on NCCT have reduced disability and mortality at 90 days.

The added value of frailty assessment as the premorbid stroke status on activities of daily living in patients with acute stroke, stratified by stroke severity

BACKGROUND

The modified Rankin scale (mRS) is extensively used for premorbid evaluation in patients with stroke; however, its limited capacity to assess functional status highlights the need for additional indicators such as frailty.

AIMS

This study aimed to assess the impact of the premorbid mRS score and frailty on daily living (ADL) activities at hospital discharge, focusing on varying stroke severities.

METHODS

This single-centre, prospective cohort study included patients with acute stroke aged ≥60 years. Key metrics included the frailty index for frailty assessment or mRS for functional status premorbid and the functional independence measure of the motor domain (FIM-M) at discharge for ADL outcomes. The patients were categorized into mild (0-4), moderate (5-15), and severe (16-42) groups based on the National Institute of Health Stroke Scale. Multiple hierarchical linear regression analyses were performed for each group to evaluate the influence of mRS and frailty on FIM-M scores.

RESULTS

In the mild stroke group, significant associations were observed with premorbid mRS3 (β = -0.183, p = 0.004), mRS4 (β = -0.234, p < 0.001), and frailty status (β = -0.227, p = 0.005) and FIM-M scores. Premorbid frailty did not show a significant association with the FIM-M scores in the moderate or severe stroke group. Frailty status notably contributed to changes in R², particularly in the mild stroke group (R² change = 0.031, p = 0.002). However, such changes were not evident in the other stroke severity groups.

CONCLUSION

This study emphasizes the importance of incorporating frailty assessments into premorbid evaluations, particularly when considering ADL outcomes in patients with mild stroke. Conversely, the significance of frailty in moderate-to-severe stroke was less evident.

Real world data in mechanical thrombectomy: who are we losing to follow-up?

BACKGROUND

Missing outcome data (MOD) is a common problem in clinical trials and registries, and a potential bias when drawing conclusions from these data. Identifying factors associated with MOD may help to increase follow-up rates and assess the need for imputation strategies. We investigated MOD in a multicenter, prospective registry study of mechanical thrombectomy (MT) in large vessel occlusion ischemic stroke.

METHODS

13 082 patients enrolled in the German Stroke Registry-Endovascular Treatment from May 2015 to December 2021 were analyzed with regard to MOD (90 day modified Rankin Scale, mRS). Univariate logistic regression analyses identified factors unbalanced between patients with and without MOD. Subgroup analyses were performed to identify patients for whom increased efforts to perform clinical follow-up after hospital discharge are needed.

RESULTS

We identified 19.7% (2580/13 082) of patients with MOD at the 90 day follow-up. MOD was more common with higher pre-stroke disability (mRS 3-5, 32.2% vs mRS 0-2, 13.7%; P<0.001), absence of bridging intravenous thrombolysis, longer time to treatment, and in patients with high post-stroke disability at discharge (mRS 3-5 vs 0-2: OR 1.234 (95% CI 1.107 to 1.375); P<0.001). In contrast, MOD was less common with futile recanalization (thrombolysis in cerebral infarction (TICI) score of 0-2a, 12.4% vs TICI 2b-3, 15.0%; P=0.001). In patients discharged alive with well documented baseline characteristics, shorter hospital stay (OR 0.992 (95% CI 0.985 to 0.998); P=0.010) and discharge to institutional care or hospital (OR 1.754 (95% CI 1.558 to 1.976); P<0.001) were associated with MOD.

CONCLUSION

MOD in routine care MT registry data was not random. Increased efforts to perform clinical follow-up are needed, especially in the case of higher pre-stroke and post-stroke disability and discharge to hospital or institutional care.

TRIAL REGISTRATION

NCT03356392.

Sex Differences in Outcomes of Late-Window Endovascular Stroke Therapy

BACKGROUND

The association between sex and outcome after endovascular thrombectomy of acute ischemic stroke is unclear. The aim of this study was to compare the clinical and safety outcomes between men and women treated with endovascular thrombectomy in the late 6-to-24-hour window period.

METHODS

This multicenter, retrospective observational cohort study included consecutive patients who underwent endovascular thrombectomy of anterior circulation stroke in the late window from 66 clinical sites in 10 countries from January 2014 to May 2022. The primary outcome was the 90-day ordinal modified Rankin Scale score. Secondary outcomes included 90-day functional independence (FI), return of Rankin (RoR) to prestroke baseline, FI or RoR, symptomatic intracranial hemorrhage, and mortality. Multivariable and inverse probability of treatment weighting methods were used. We explored the interaction of sex with baseline characteristics on the outcomes ordinal modified Rankin Scale and FI or RoR.

RESULTS

Of 1932 patients, 1055 were women and 877 were men. Women were older (77 versus 69 years), had higher rates of atrial fibrillation, hypertension, and greater prestroke disability, but there was no difference in baseline National Institutes of Health Stroke Scale score. Inverse probability of treatment weighting analysis showed no difference between women and men in ordinal modified Rankin Scale (odds ratio, 0.98 [95% CI, 0.79-1.21]), FI or RoR (odds ratio, 0.98 [95% CI, 0.78-1.22]), severe disability or mortality (odds ratio, 0.99 [95% CI, 0.80-1.23]). The multivariable analysis of the above end points was concordant. There were no interactions between baseline characteristics and sex on the outcomes of ordinal modified Rankin Scale and FI or RoR.

CONCLUSIONS

In late presenting patients with anterior circulation stroke treated with endovascular thrombectomy in the 6 to 24-hour window, there was no difference in clinical or safety outcomes between men and women.

Endovascular treatment of acute ischemic stroke in patients with pre-morbid disability: a meta-analysis

BACKGROUND

Trials of endovascular thrombectomy (EVT) for acute stroke have excluded patients with pre-morbid disability. Observational studies may help inform consideration of EVT in this population. We aimed to assess the effectiveness and safety of EVT in patients with pre-morbid disability.

METHODS

According to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we searched MEDLINE and Embase for studies describing outcomes in patients with pre-morbid disability (modified Rankin Scale (mRS) 2-5), treated with EVT or medical management (MM). Random-effects meta-analysis was used to pool outcomes including 90-day return to baseline mRS, symptomatic intracerebral hemorrhage (sICH), and 90-day mortality.

RESULTS

We analyzed 14 studies of patients with pre-morbid disability (mRS 2-5, 1373 EVT and 253 MM). The rate of return to baseline mRS was 30.0% (95% CI 25.3% to 34.7%) in patients treated with EVT. Compared with medical therapy, EVT was associated with a higher likelihood of return to baseline mRS (OR 2.37, 95% CI 1.39 to 4.04) and a trend towards lower mortality (OR 0.68, 95% CI 0.46 to 1.02), with similar odds of sICH (OR 1.01, 95% CI 0.49 to 2.08). In studies comparing patients with versus without pre-morbid disability treated with EVT, similar results were found except that pre-morbid disability, when defined more strictly as mRS 3-5, was associated with mortality (OR 3.49, p<0.001).

CONCLUSION

In eligible patients with pre-morbid disability, observational studies suggest that EVT carries a higher chance of return to baseline mRS compared with patients treated with MM or without pre-morbid disability, although with higher mortality than patients without pre-morbid disability. These findings argue against the routine exclusion of such patients from EVT and merit validation with randomized trials.

Outcomes following thrombectomy for acute large vessel occlusion beyond 24 hours or with unknown time of onset

BACKGROUND

Endovascular thrombectomy (EVT) is recommended in medically eligible patients with large vessel occlusions (LVO) within 24 hours of symptom onset. While there is evidence that EVT ≥24h after last known well (LKW) is associated with favorable outcomes in patients who meet DAWN/DEFUSE-3 criteria, it is unknown if more liberal criteria can be applied.

METHODS

A single center, prospective observational cohort of consecutive adult stroke patients was queried for symptomatic occlusions of the internal carotid (ICA) or proximal middle cerebral (M1) arteries (October 2019-January 2022), with a National Institutes of Health Stroke Scale (NIHSS) ≥6, pre-stroke modified Rankin Scale (mRS) 0-2, and Alberta Stroke Program Early Computed Tomography Scale score 3-10. These inclusion criteria were extrapolated from recently published data indicating a benefit with EVT with more liberal patient selection. Patients who underwent EVT ≥24h after LKW were compared against those treated medically. The primary outcome was a good functional outcome (90-day mRS 0-2), which was evaluated using multivariable logistic regression.

RESULTS

Of the 27 included patients, the median age was 65y (IQR 49-76) with a median NIHSS of 15 (IQR 8-26), and 17 (63.0%) underwent EVT (median LKW-to-puncture 35.5h (IQR 26.9-65.8h). The primary outcome was no different with EVT in unadjusted regression (OR 1.17, 95%CI 0.17-8.09), and there remained no association across all multivariable models tested. Age, pre-stroke disability, and M1 occlusions were non-significantly associated with the primary outcome (p>0.05). There was a non-significant trend indicating a favorable shift in 90-day mRS with EVT (proportional OR 2.04, 95%CI 0.44-9.48).

CONCLUSIONS

Using more liberal inclusion criteria for EVT in the ultra-extended window, there was no statistically significant difference in the rate of good functional outcome with EVT. Larger studies are called upon to evaluate outcomes when more liberal criteria are used to assess thrombectomy eligibility.

Endovascular vs Medical Management for Late Anterior Large Vessel Occlusion With Prestroke Disability: Analysis of CLEAR and RESCUE-Japan

BACKGROUND AND OBJECTIVES

Current guidelines do not address recommendations for mechanical thrombectomy (MT) in the extended time window (>6 hours after time last seen well [TLSW]) for large vessel occlusion (LVO) patients with preexisting modified Rankin Scale (mRS) > 1. In this study, we evaluated the outcomes of MT vs medical management in patients with prestroke disability presenting in the 6- to 24-hour time window with acute LVO.

METHODS

We analyzed a multinational cohort (61 sites, 6 countries from 2014 to 2020) of patients with prestroke (or baseline) mRS 2 to 4 and anterior circulation LVO treated 6-24 hours from TLSW. Patients treated in the extended time window with MT vs medical management were compared using multivariable logistic regression and inverse probability of treatment weighting (IPTW). The primary outcome was the return of Rankin (ROR, return to prestroke mRS by 90 days).

RESULTS

Of 554 included patients (448 who underwent MT), the median age was 82 years (interquartile range [IQR] 72-87) and the National Institutes of Health Stroke Scale (NIHSS) was 18 (IQR 13-22). In both MV logistic regression and IPTW analysis, MT was associated with higher odds of ROR (adjusted OR [aOR] 3.96, 95% CI 1.78-8.79 and OR 3.10, 95% CI 1.20-7.98, respectively). Among other factors, premorbid mRS 4 was associated with higher odds of ROR (aOR, 3.68, 95% CI 1.97-6.87), while increasing NIHSS (aOR 0.90, 95% CI 0.86-0.94) and decreasing Alberta Stroke Program Early Computed Tomography Scale score (aOR per point 0.86, 95% CI 0.75-0.99) were associated with lower odds of ROR. Age, intravenous thrombolysis, and occlusion location were not associated with ROR.

DISCUSSION

In patients with preexisting disability presenting in the 6- to 24-hour time window, MT is associated with a higher probability of returning to baseline function compared with medical management.

CLASSIFICATION OF EVIDENCE

This investigation's results provide Class III evidence that in patients with preexisting disability presenting 6-24 hours from the TLSW and acute anterior LVO stroke, there may be a benefit of MT over medical management in returning to baseline function.

Successful thrombectomy is beneficial in patients with pre-stroke disability: Results from an international multicenter cohort study

BACKGROUND

Patients with pre-stroke disability, defined as a modified Rankin Scale (mRS) ≥3, were excluded from most trials of endovascular thrombectomy (EVT) for acute stroke. We sought to evaluate the prognostic factors associated with favorable outcome in stroke patients with known disability undergoing EVT, and the impact of successful reperfusion.

METHODS

Consecutive acute stroke patients with pre-stroke disability, undergoing EVT, were retrospectively collected between 2016 to 2019 from a Canadian cohort and a multicenter French cohort (Endovascular Treatment in Ischemic Stroke registry-ETIS). Favorable outcome was defined as an mRS equal to pre-stroke mRS. Patients achieving successful reperfusion (defined as a modified Thrombolysis in Cerebral Infarction score of 2b/3) were compared with patients without successful reperfusion to determine if successful EVT was associated with better functional outcomes.

RESULTS

Among 6220 patients treated with EVT, 280 (4.5%) patients with a pre-stroke mRS ≥3 were included. Sixty-one patients (21.8%) had a favorable outcome and 146 (52.1%) died at 3 months. Patients with successful reperfusion had a higher proportion of favorable 90-day mRS (27.6% versus 19.6%, p = 0.025) and a lower mortality (48.3% versus 69.6%, p = 0.008) than patients without successful reperfusion. After adjusting for baseline prognostic factors, successful reperfusion defined by TICI ≥2b was associated with favorable functional outcome (OR 3.16 CI95% [1.11-11.5]; p 0.048).

CONCLUSION

In patients with pre-stroke disability, successful reperfusion is associated with a greater proportion of favorable outcome and lower mortality.

Cost-Effectiveness of Endovascular Treatment in Large Vessel Occlusion Stroke With Mild Prestroke Disability: Results From the HERMES Collaboration

BACKGROUND

The clinical and economic benefit of endovascular treatment (EVT) in addition to best medical management in patients with stroke with mild preexisting symptoms/disability is not well studied. We aimed to investigate cost-effectiveness of EVT in patients with large vessel occlusion and mild prestroke symptoms/disability, defined as a modified Rankin Scale score of 1 or 2.

METHODS

Data are from the HERMES collaboration (Highly Effective Reperfusion Evaluated in Multiple Endovascular Stroke Trials), which pooled patient-level data from 7 large, randomized EVT trials. We used a decision model consisting of a short-run model to analyze costs and functional outcomes within 90 days after the index stroke and a long-run Markov state transition model (cycle length of 12 months) to estimate expected lifetime costs and outcomes from a health care and a societal perspective. Incremental cost-effectiveness ratio and net monetary benefits were calculated, and a probabilistic sensitivity analysis was performed.

RESULTS

EVT in addition to best medical management resulted in lifetime cost savings of $2821 (health care perspective) or $5378 (societal perspective) and an increment of 1.27 quality-adjusted life years compared with best medical management alone, indicating dominance of additional EVT as a treatment strategy. The net monetary benefits were higher for EVT in addition to best medical management compared with best medical management alone both at the higher (100 000$/quality-adjusted life years) and lower (50 000$/quality-adjusted life years) willingness to pay thresholds. Probabilistic sensitivity analysis showed decreased costs and an increase in quality-adjusted life years for additional EVT compared with best medical management only.

CONCLUSIONS

From a health-economic standpoint, EVT in addition to best medical management should be the preferred strategy in patients with acute ischemic stroke with large vessel occlusion and mild prestroke symptoms/disability.

Influence of pre-stroke dependency on safety and efficacy of endovascular therapy: A systematic review and meta-analysis

Background and purpose

In the landmark trials studying endovascular thrombectomy (EVT), pre-stroke dependent (PSD) patients were generally excluded. This systematic review and meta-analysis aimed to compare the safety and efficacy of EVT between PSD and pre-stroke independent (PSI) patients.

Methods

We searched CENTRAL, Embase, and Ovid MEDLINE up to 11 November 2021 for studies assessing PSD and PSI patients, which were separately defined as pre-stroke mRS score >2 or >1, and ≤2 or ≤1 accordingly. Two authors extracted data and assessed the risk of bias. A meta-analysis was carried out using the random-effects model. Adjusted OR and 95% CI were used to estimate adjusted pool effects. The main outcomes included favorable outcomes, successful recanalization, symptomatic intracranial hemorrhage, and 90-day mortality.

Results

A total of 8,004 records met the initial search strategy, and ten studies were included in the final decision. Compared with PSImRS≤2, PSDmRS>2 had a lower favorable outcome (OR 0.51; 95% CI, 0.33-0.79) and higher 90-day mortality (OR 3.32; 95% CI, 2.77-3.98). No significant difference was found in successful recanalization and sICH. After adjustment, only 90-day mortality (aOR 1.99; 95% CI, 1.58-2.49) remained significantly higher in PSDmRS>2. Compared with PSImRS≤1, PSDmRS>1 had lower 90-day mortality (OR, 3.10; 95% CI, 1.84-5.24). No significant difference was found regarding the favorable outcome, successful recanalization, and sICH. After adjustment, no significant difference was found in a favorable outcome, but a higher rate of 90-day mortality (aOR, 2.13; 95% CI, 1.66-2.72) remained in PSDmRS>1.

Conclusions

PSD does not innately influence the EVT outcomes regarding sICH and favorable outcomes but may increase the risk of 90-day mortality. Until further evidence is available, it is reasonable to suggest EVT for patients with PSD.

Endovascular thrombectomy in acute ischemic stroke patients with prestroke disability (mRS ≥2): A systematic review and meta-analysis

Objective

The effect of endovascular thrombectomy (EVT) in acute ischemic stroke patients with prestroke disability (modified Rankin Scale score, mRS) ≥2) has not been well-studied. This study aimed to assess the safety and benefit of EVT in patients with prestroke disability.

Methods

According to PRISMA guidelines, literature searching was performed using PubMed, Embase, and Cochrane databases, for a series of acute ischemic stroke patients with prestroke mRS ≥2 treated by EVT. Random-effects meta-analysis was used to pool the rate of return to prestroke mRS and mortality at 3-month follow-up.

Results

In total, 13 observational studies, with 2,625 patients, were analyzed. The rates of return to prestroke mRS in patients with prestroke mRS of 2–4 were 20% (120/588), 27% (218/827), and 31% (34/108), respectively. Patients with prestroke disability treated by EVT had a higher likelihood of return to prestroke mRS (relative risk, RR, 1.86; 95% CI 1.28–2.70) and a lower likelihood of mortality (RR 0.75; 95%CI 0.58–0.97) compared with patients with standard medical treatment. Successful recanalization (Thrombolysis in Cerebral Infarction grade 2b-3) after EVT gave a higher likelihood of return to prestroke mRS (RR 2.04; 95% CI 1.17–3.55) and lower mortality (RR 0.72; 95% CI 0.62–0.84) compared with unsuccessful reperfusion.

Conclusions

Acute ischemic stroke patients with prestroke disability may benefit from EVT. Withholding EVT on the sole ground of prestroke disabilities may not be justified.

Systematic Review Registration:https://www.crd.york.ac.uk/prospero/.

Multivariable Prediction Model for Futile Recanalization Therapies in Patients With Acute Ischemic Stroke

BACKGROUND AND OBJECTIVES

Very poor outcome despite IV thrombolysis (IVT) and mechanical thrombectomy (MT) occurs in approximately 1 of 4 patients with ischemic stroke and is associated with a high logistic and economic burden. We aimed to develop and validate a multivariable prognostic model to identify futile recanalization therapies (FRTs) in patients undergoing those therapies.

METHODS

Patients from a prospectively collected observational registry of a single academic stroke center treated with MT and/or IVT were included. The data set was split into a training (N = 1,808, 80%) and internal validation (N = 453, 20%) cohort. We used gradient boosted decision tree machine learning models after k-nearest neighbor imputation of 32 variables available at admission to predict FRT defined as modified Rankin scale 5-6 at 3 months. We report feature importance, ability for discrimination, calibration, and decision curve analysis.

RESULTS

A total of 2,261 patients with a median (interquartile range) age of 75 years (64-83 years), 46% female, median NIH Stroke Scale 9 (4-17), 34% IVT alone, 41% MT alone, and 25% bridging were included. Overall, 539 (24%) had FRT, more often in MT alone (34%) as compared with IVT alone (11%). Feature importance identified clinical variables (stroke severity, age, active cancer, prestroke disability), laboratory values (glucose, C-reactive protein, creatinine), imaging biomarkers (white matter hyperintensities), and onset-to-admission time as the most important predictors. The final model was discriminatory for predicting 3-month FRT (area under the curve 0.87, 95% CI 0.87-0.88) and had good calibration (Brier 0.12, 0.11-0.12). Overall performance was moderate (F1-score 0.63 ± 0.004), and decision curve analyses suggested higher mean net benefit at lower thresholds of treatment (up to 0.8).

CONCLUSIONS

This FRT prediction model can help inform shared decision making and identify the most relevant features in the emergency setting. Although it might be particularly useful in low resource healthcare settings, incorporation of further multifaceted variables is necessary to further increase the predictive performance.

Evaluation of Functional Recovery Following Thrombectomy in Patients With Large Vessel Occlusion and Prestroke Disability

IMPORTANCE

It is uncertain whether thrombectomy is associated with benefits in patients with prestroke disability.

OBJECTIVE

To evaluate the use of thrombectomy for patients with large vessel occlusion and prestroke disability.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study included patients with large vessel occlusion stroke and prestroke disability (modified Rankin Scale score, 3 or 4) admitted to a single tertiary care center between January 1, 2006, and June 30, 2019 (controls: 2006-2015; thrombectomy: 2015-2019). Follow-up was conducted at 90 days. Data analysis was performed from November 1 to December 31, 2021.

EXPOSURES

Use of thrombectomy vs no thrombectomy.

MAIN OUTCOMES AND MEASURES

The primary outcome was functional recovery at 90 days defined as clinical recovery to the functional status before stroke onset. Secondary outcomes included functional dependency, mortality, early neurologic improvement, and recanalization.

RESULTS

Among 205 patients (149 women [72.7%]; median age, 82 years [IQR, 75-87 years]), 102 individuals (49.8%) received thrombectomy and 103 (50.2%) were controls. Thrombectomy was significantly associated with functional recovery (thrombectomy, 20 [19.6%]; controls, 8 [7.8%]; adjusted difference, 9.4%; 95% CI, 2.2% to 16.7%; P = .005). Secondary outcomes showed differences in mortality, early neurologic improvement, and recanalization in favor of thrombectomy treatment. The rate of functional dependency did not differ significantly between the 2 groups (adjusted difference, 8.9%; 95% CI, -2.5% to 20.2%; P = .13). The rate of functional recovery after thrombectomy was 44.0% for patients with early neurologic improvement, 29.4% for patients with small infarct volume (<50 mL), and 7.0% for patients with neither of these parameters.

CONCLUSIONS AND RELEVANCE

Findings of this study suggest that selected patients with prestroke disability may benefit from thrombectomy. However, the thrombectomy-associated increase in functional recovery was small. Therefore, routine use of thrombectomy may not be beneficial among patients with a large ischemic core and infarct volumes less than 50 mL may be necessary to obtain functional recovery. Patients with higher chances of functional recovery are also at an increased risk of survival with substantial disability, indicating potential harms from the intervention; further studies are needed.

The Problem of Restrictive Thrombectomy Trial Eligibility Criteria

Since 2015, a series of endovascular trials transformed the management of patients with large vessel occlusion stroke. Most thrombectomy trials used restrictive eligibility criteria to optimize the chances of showing that thrombectomy could work. The problem arises when generalizing trial results into evidence-based recommendations. Many organizations, oblivious of this problem, translated verbatim restrictive trial eligibility criteria into authoritative guidelines, which limit the use of thrombectomy to highly selected patients. The clinical problem becomes as follows: what to do for all other stroke patients equally in need of care? The cycle of restrictive trial eligibility criteria, corresponding restrictive guidelines, observational studies of unvalidated practices showing other patients benefit, a new trial is needed, has been repeated often. Thrombectomy trials ought to have included all patients that could potentially benefit. If the signal that was looked for by restricting eligibility is at risk of being lost in the noise generated by the heterogeneity of patients, D. Sackett proposed a solution: to use the same criteria, not to select some patients and exclude others but to prespecify the subgroup of patients most likely to benefit. In this commentary, we propose a tiered approach, where the boundaries of treatment beneficiaries can be more rigorously tested and confirmed. Identification of these patients before the development of guidelines, which would have otherwise neglected these individuals, may open innumerable treatment opportunities to those who will instead be denied of them.

Stenting and Angioplasty in Neurothrombectomy: Matched Analysis of Rescue Intracranial Stenting Versus Failed Thrombectomy

BACKGROUND:

Successful reperfusion is one of the strongest predictors of functional outcomes after mechanical thrombectomy (MT). Despite continuous advancements in MT technology and techniques, reperfusion failure still occurs in ≈15% to 30% of patients with large vessel occlusion strokes undergoing MT. We aim to evaluate the safety and efficacy of rescue intracranial stenting for large vessel occlusion stroke after failed MT.

METHODS:

The SAINT (Stenting and Angioplasty in Neurothrombectomy) Study is a retrospective analysis of prospectively collected data from 14 comprehensive stroke centers through January 2015 to December 2020. Patients were included if they had anterior circulation large vessel occlusion stroke due to intracranial internal carotid artery and middle cerebral artery-M1/M2 segments and failed MT. The cohort was divided into 2 groups: rescue intracranial stenting and failed recanalization (modified Thrombolysis in Cerebral Ischemia score 0–1). Propensity score matching was used to balance the 2 groups. The primary outcome was the shift in the degree of disability as measured by the modified Rankin Scale at 90 days. Secondary outcomes included functional independence (90-day modified Rankin Scale score 0–2). Safety measures included symptomatic intracranial hemorrhage and 90-day mortality.

RESULTS:

A total of 499 patients were included in the analysis. Compared with the failed reperfusion group, rescue intracranial stenting had a favorable shift in the overall modified Rankin Scale score distribution (acOR, 2.31 [95% CI, 1.61–3.32]; P <0.001), higher rates of functional independence (35.1% versus 7%; adjusted odds ratio [aOR], 6.33 [95% CI, 3.14–12.76]; P <0.001), and lower mortality (28% versus 46.5%; aOR, 0.55 [95% CI, 0.31–0.96]; P =0.04) at 90 days. Rates of symptomatic intracerebral hemorrhage were comparable across both groups (7.1% versus 10.2%; aOR, 0.99 [95% CI, 0.42–2.34]; P =0.98). The matched cohort analysis demonstrated similar results. Specifically, rescue intracranial stenting (n=107) had a favorable shift in the overall modified Rankin Scale score distribution (acOR, 3.74 [95% CI, 2.16–6.57]; P <0.001), higher rates of functional independence (34.6% versus 6.5%; aOR, 10.91 [95% CI, 4.11–28.92]; P <0.001), and lower mortality (29.9% versus 43%; aOR, 0.49 [95% CI, 0.25–0.94]; P =0.03) at 90 days with similar rates of symptomatic intracerebral hemorrhage (7.5% versus 11.2%; aOR, 0.87 [95% CI, 0.31–2.42]; P =0.79) compared with patients who failed to reperfuse (n=107). There was no heterogeneity of treatment effect across the prespecified subgroups for improvement in functional outcomes.

CONCLUSIONS:

Acute intracranial stenting appears to be a safe and effective rescue strategy in patients with large vessel occlusion stroke who failed MT. Randomized multicenter trials are warranted.

Thrombolysis for Acute Ischemic Stroke in Patients With Premorbid Disability: A Meta-Analysis

BACKGROUND

Randomized controlled trials for the use of alteplase in acute ischemic stroke have excluded or had little representation of patients with prestroke disability, and the benefit of alteplase in this population remains uncertain. We performed a systematic review and meta-analysis to examine the outcomes of thrombolysis in patients with premorbid disability.

METHODS

We performed a systematic review in accordance with the Meta-Analysis of Observational Studies in Epidemiology guidelines and retrieved studies reporting intravenous thrombolysis (IVT) in patients with prestroke disability (modified Rankin Scale score, 3-5) with acute ischemic stroke, either compared with untreated patients or treated patients without premorbid disability. The primary outcome was the return to premorbid disability at 90 days. Secondary outcomes included rate and odds ratio of favorable functional outcome at 90 days (modified Rankin Scale score 0-2 or return to premorbid modified Rankin Scale), symptomatic intracerebral hemorrhage (sICH), and 90-day mortality.

RESULTS

Eight articles were included involving 103 988 patients. Patients with disability treated with IVT had better odds of returning to baseline function compared with those who did not receive IVT (odds ratio, 7.26 [95% CI, 2.51-21.02]). Mortality and rates of sICH were not significantly different between patients with disability treated with IVT and those not treated, although there were numerically more sICHs in the IVT group. Return to baseline function was not significantly different between patients with and without prestroke disability (odds ratio, 1.46 [95% CI, 0.75-2.83]). The rates of sICH were not significantly different in patients with and without premorbid disability. However, mortality was 3× higher in patients with premorbid disability than in those without premorbid disability (38.2% versus 12.6%).

CONCLUSIONS

The use of IVT in patients with disability was associated with better outcomes compared with patients who did not receive IVT without statistically significant added risks of sICH or mortality. When compared with those without disability, there was no significant difference in the return to baseline function or sICH. High-quality data comparing treated versus untreated patients with premorbid disability are needed to clarify this issue.

REGISTRATION

URL: https://www.crd.york.ac.uk/PROSPERO/; Unique identifier: CRD42021240499.

Outcome of Endovascular Thrombectomy in Pre-stroke Dependent Patients With Acute Ischemic Stroke: A Systematic Review and Meta-Analysis

Introduction

Endovascular thrombectomy (EVT) is a well-established and effective therapeutic option for patients that meet certain criteria. However, this modality is not well studied in patients with pre-existing disability. The aim of the present study was to investigate the impact of mechanical thrombectomy in patients with acute onset ischemic stroke and pre-stroke dependency (PSD) in regard to their clinical outcome and mortality.

Materials and Methods

The MEDLINE, Scopus, and Cochrane Library databases were comprehensively searched with a cut-off date of December 11th, 2021. We performed meta-analysis to investigate the 90-day clinical outcome, the 90-day mortality, and the rate of symptomatic intracerebral hemorrhage (sICH) between the PSD (modified Rankin Scale score ≥ 3) and non-PSD (modified Rankin Scale score = 0-2) groups who underwent EVT for acute onset ischemic stroke.

Results

Six studies were included in the meta-analysis involving 4,543 cases with no PSD and 591 cases with PSD. The non-PSD group showed a statistically significant better clinical outcome at 90 days compared to the PSD group [RR (95% CI) = 1.44 (1.06, 1.85); p z = 0.02]. The non-PSD group demonstrated a statistically significant lower risk of death at 90 days in comparison to the PSD group [RR (95% CI) = 0.45 (0.41, 0.50); p z < 0.01]. Lastly, the rate of sICH was comparable between the two groups [RR (95% CI) = 0.89 (0.64, 1.24); p z = 0.48].

Discussion

We report a higher rate of unfavorable clinical outcome and a higher mortality rate in patients with PSD undergoing EVT compared to those with no previous disability. However, there was a significant proportion of PSD cases who fared well post-procedurally, indicating that PSD patients should not be routinely excluded from mechanical thrombectomy.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021284181, identifier: CRD42021284181.