Stroke Etiology and Outcomes after Endovascular Thrombectomy: Results from the SITS Registry and a Meta-Analysis

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.

Could emergency admission plasma D-dimer level predict first pass effect of stent retriever thrombectomy in acute ischemic stroke?

BACKGROUND

Evidence on plasma biomarkers to identify first pass effect (FPE) in patients with acute ischemic stroke (AIS) with large vessel occlusion (LVO) treated with thrombectomy is limited.

PURPOSE

To evaluate whether plasma D-dimer could predict FPE.

MATERIAL AND METHODS

Consecutive patients with LVO who underwent first-line stent retriever thrombectomy at our center between January 2018 and August 2021 were enrolled. Patients were classified into the FPE (modified Thrombolysis in Cerebral Infarction [mTICI] ≥2c) group or non-FPE (mTICI 0-2b) group based on angiographic outcomes. Logistic regression analysis was performed to determine the predictors of FPE. The overall ability of D-dimer levels in predicting FPE was evaluated using receiver operating characteristic (ROC) curves.

RESULTS

In total, 313 patients were included; 88 (28.1%) patients achieved FPE. Compared to those with non-FPE, patients with FPE had more diabetes mellitus history, lower D-dimer levels, higher clot burden score, a higher proportion of M1 middle cerebral artery, and a higher proportion of main stem occlusion pattern (P <0.05). After adjusting for potential variables, D-dimer levels (OR=0.81, 95% CI=0.52-0.96), clot burden score (OR=1.76, 95% CI=1.38-2.87), and main stem occlusion pattern (OR=1.85, 95% CI=1.19-2.62) remained independently associated with FPE. Based on the ROC analysis, the D-dimer as a predictor for predicting FPE presented with a specificity of 79%, a negative predictive value of 87%, and an area under the curve of 0.761.

CONCLUSION

Low emergency admission plasma D-dimer level is an independent predictor of FPE in patients with AIS treated with stent retriever thrombectomy.

Outcome Comparison of Endovascular Treatment for Acute Large Vessel Occlusion Due to Large Artery Atherosclerosis and Cardioembolism in the Chinese Population: Data from the ANGEL Registry

Background and Purpose

Studies on outcome comparison after endovascular treatment (EVT) for large vessel occlusion (LVO) between large artery atherosclerosis (LAA) and cardioembolism (CE) in the Asian population are scarce. We aimed to compare the baseline characteristics and clinical outcomes after EVT for anterior circulation LVO with LAA and CE in the Chinese population.

Methods

Patients were selected from the ANGEL registry and divided into LAA and CE groups. The primary outcome was the 90-day modified Rankin Scale (mRS) 0-2. The secondary outcomes were 90-day mRS distribution, 90-day mRS 0-1, 90-day mRS 0-3, and early neurological improvement. The safety outcomes included death, symptomatic intracranial hemorrhage, and any intracranial hemorrhage. We conducted logistic regression models with adjustments to compare the outcomes.

Results

A total of 632 patients were included, of whom, 488 were in the LAA group and 144 were in the CE group. No significant difference in 90-day mRS 0-2 was observed between LAA and CE groups (55.7%vs.43.1%, odds ratio[OR] 1.19, 95% confidence interval(CI), 0.92-1.53, P=0.190). The LAA group exhibited a higher frequency of mRS 0-3 compared to the CE group (69.1% vs 32.6%, OR1.32, 95% CI 1.02-1.72, P=0.038). However, the incidence of death within 90 days did not significantly differ between the LAA and CE groups (10.9%vs.24.3%, OR0.91, 95% CI0.66-1.25, P=0.545), nor did the occurrences of symptomatic intracranial hemorrhage(SICH) (4.5%vs.9.7%,OR1.08, 95% CI 0.65-1.78, P=0.779) or intracranial hemorrhage(ICH) (21.9%vs.30.6%, OR 0.94, 95% CI0.71-1.25, P=0.680). Moreover, no significant disparities were detected in other outcomes between the two groups (All P>0.05).

Conclusion

In the ANGEL registry, a higher prevalence of patients undergoing EVT for acute anterior circulation LVO with LAA was found than those with CE. However, our study revealed that the efficacy and safety of EVT remained consistent regardless of the stroke's etiology such as LAA or CE.

Endovascular therapy beyond 24 hours for anterior circulation large vessel occlusion or stenosis in acute ischemic stroke: a retrospective study

Background

To assess the clinical and safety outcomes of endovascular treatment (EVT) administered more than 24 h after the onset of symptoms in patients with acute ischemic stroke resulting from anterior circulation large-vessel occlusion or stenosis (AIS-ACLVO/S).

Methods

We enrolled consecutive AIS-ACLVO/S patients who received EVT in our hospital between January 2019 and February 2022 and divided them into two groups based on the time from AIS onset to EVT: EVT < 24 h group and EVT >24 h group. The successful reperfusion (modified thrombolysis in cerebral infarction, [mTICI] ≥2b), 90-day modified Rankin Scale score (mRS), intracranial hemorrhage (ICH), and symptomatic ICH (sICH), as well as mortality, were analyzed in the two groups of patients.

Results

A total of 239 patients were included in the study, with 214 patients in the EVT < 24 h group (67.8 ± 0.8 years, 126 males) and 25 patients in the EVT > 24 h group (62.80 ± 2.0 years, 22 males). Both groups were similar in terms of hypertension, diabetes history, responsible vessels, and Alberta stroke program early computed tomography scores (p > 0.05). However, the EVT < 24 h group had significantly higher age, history of atrial fibrillation, proportion of patients receiving intravenous thrombolysis, and NIHSS scores before EVT than the EVT > 24 h group. AIS etiology differed between the groups, with more cases of large artery atherosclerosis in the EVT > 24-h group and more cases of cardioembolism in the EVT < 24-h group. Successful reperfusion (mTICI ≥2b), ICH, and sICH were similar between the groups. The 90-day functional independence rate (mRS ≤ 2) was significantly higher in the EVT > 24-h than in the EVT < 24-h group (80% vs. 39.7%, p < 0.001), while the 90-day mortality rate was lower in the EVT > 24-h group (0% vs. 24.8%, p < 0.001).

Conclusion

In our study, we found that EVT beyond 24 h of symptom onset in patients selected with multimodal MR screening, was associated with high functional independence rates and low mortality. Larger or randomized studies are needed to confirm these findings.

Intravenous tirofiban following successful reperfusion in intracranial large artery atherosclerotic stroke: A secondary analysis of a randomized clinical trial

OBJECTIVE

This study aimed to investigate whether treatment with adjunct intravenous tirofiban is associated with improved outcomes following successful reperfusion in patients with intracranial atherosclerotic stroke.

METHODS

Patients with intracranial large artery atherosclerotic (LAA) stroke and an expanded Treatment in Cerebral Ischemia angiographic score of 2b50 to 3 from the Effect of Intravenous Tirofiban versus Placebo Before Endovascular Thrombectomy on Functional Outcomes in Large Vessel Occlusion Stroke (RESCUE BT) trial were included. The primary outcome was the difference in proportion of independent functional outcome (modified Rankin score of 0-2 at 90 days). Safety outcomes included the rates of symptomatic intracranial hemorrhage (sICH) and 90-day mortality.

RESULTS

Among the 382 patients with intracranial LAA stroke and successful reperfusion, 175 patients (45.8%) were treated with intravenous tirofiban and 207 (54.2%) with placebo. The proportion of patients with independent functional outcome at 90 days was 54.3% (95 out of 175) with tirofiban and 44.0% (91 out of 207) with placebo (adjusted odds ratio [aOR], 1.58; 95% CI, 1.02-2.44; p = 0.04). Intravenous tirofiban was not significantly associated with an increased risk of sICH (12/175 [6.9%] vs. 11/207 [5.3%]; aOR, 1.41; 95% CI, 0.59-3.34; p = 0.44) or 90-day mortality (21/175 [12.0%] vs. 34/207 [16.4%]; aOR, 0.71; 95% CI, 0.38-1.31; p = 0.27).

INTERPRETATION

Among patients with acute intracranial LAA stroke and successful reperfusion following endovascular thrombectomy, adjunct intravenous tirofiban was associated with a higher rate of independent functional outcome, without higher rates of sICH or mortality. Confirmatory randomized trials in these patients are desirable.

Management and Prognosis of Acute Stroke in Atrial Fibrillation

Atrial fibrillation (AF) is an important risk factor for ischemic stroke (IS). Oral anticoagulation (OAC) significantly reduces the risk of IS in AF but also increases the risk of systemic bleeding, including intracerebral hemorrhage (ICH). AF-related strokes are associated with greater disability and mortality compared to non-AF strokes. The management of patients with AF-related strokes is challenging, and it involves weighing individual risks and benefits in the acute treatment and preventive strategies of these patients. This review summarizes the current knowledge of the acute management of ischemic and hemorrhagic stroke in patients with AF, and the prognosis and potential implications for management both in the acute and long-term setting.

Anticoagulation under-utilization in atrial fibrillation patients is responsible for a large proportion of strokes requiring endovascular therapy

OBJECTIVES

Atrial fibrillation (AF) is responsible for 30-50% of large strokes requiring endovascular thrombectomy (EVT). Anticoagulation (AC) underutilization is a common source of AF-related stroke. We compared antithrombotic medications among stroke patients with AF that did or did not undergo EVT to determine if AC underutilization disproportionately results in strokes requiring EVT, while quantifying the proportion of likely preventable thrombectomies.

METHODS

This retrospective single-center cohort included consecutive patients admitted with acute ischemic stroke between 2016 and 2021. Patients were categorized based on the presence of AF, and pre-admission antithrombotic medications were compared between those who underwent EVT and those who didn't. The reason for not being on AC was abstracted from the medical record, and patients were categorized as either AC eligible or AC contraindicated.

RESULTS

Of 3092 acute ischemic stroke patients, 644 had a history of AF, 213 of whom underwent EVT. Patients who required EVT were more likely to not be taking any antithrombotics prior to admission (34% vs 24%, p=0.007) or have subtherapeutic INR on admission if taking warfarin (83% vs 63%; p = 0.046). Among the AF-EVT patients, 44% were taking AC, and only 31% were adequately anticoagulated. Only 8% of AF-EVT patients who were not on pre-admission AC had a clear contraindication, and 94% were ultimately discharged on AC.

CONCLUSIONS

Lack of antithrombotic therapy in AF patients disproportionately contributes to strokes requiring EVT. A small minority of AF patients have contraindications to AC, so adequate anticoagulation can prevent a remarkable number of strokes requiring EVT.

Collateral Flow in Intracranial Atherosclerotic Disease

Intracranial atherosclerotic disease (ICAD) is a major cause of ischemic stroke and transient ischemic attack (TIA) worldwide. The culprit of ICAD is frequently a high-grade intracranial atherosclerotic stenosis (ICAS) pertaining to the infarct territory, and by then, the ICAS is described as symptomatic. A high-grade ICAS may progressively limit cerebral perfusion downstream, demanding collateral compensation. Collateral circulation refers to the pre-existing and dynamic emergence of vascular channels that maintain and compensate for a failing principal vascular route. Collaterals through the Circle of Willis and leptomeningeal circulation are of utmost importance in this regard. In this article, we first discussed the epidemiology, stroke mechanisms, contemporary therapeutics, and prognosis of symptomatic ICAD. Then, we reviewed the collateral routes in ICAS, factors associated with recruitment and development of the collaterals and diagnostic imaging modalities in assessing the origin and function of collateral circulation. We discussed the associations between collateral circulation and clinical outcomes after acute reperfusion treatment in ICAD-related ischemic strokes with or without large vessel occlusion (LVO). We also conducted a systematic review and meta-analysis on the associations of collateral circulation with the risk of recurrent stroke and the functional outcome in symptomatic ICAS patients on medical treatment as secondary stroke prevention. Finally, we summarized current evidence in these aspects and proposed the future directions.

Intra-arterial tenecteplase is safe and may improve the first-pass recanalization for acute ischemic stroke with large-artery atherosclerosis: the BRETIS-TNK trial

Background and purpose

The first-pass recanalization of endovascular treatment (EVT) is closely correlated with clinical outcome of patients with large vessel occlusion (LVO) stroke. The aim of the study was to explore whether intra-arterial tenecteplase (TNK) during the first pass of EVT can increase first-pass successful reperfusion and improve the neurological outcome in AIS-LVO patients.

Materials and methods

The BRETIS-TNK trial (ClinicalTrials.gov Identifier: NCT04202458) was a prospective, single-arm, single center study. Twenty-six eligible AIS-LVO patients with large-artery atherosclerosis etiology were consecutively enrolled from December 2019 to November 2021. Intra-arterial TNK (4 mg) after microcatheter navigation through the clot was administered, followed by TNK (0.4  mg/min) given continuously for 20  min after the first retrieval attempt of EVT without confirmation of the reperfusion status by DSA. The 50 control patients comprised of a historical cohort before the BRETIS-TNK trial (from March 2015 to November 2019). Successful reperfusion was defined as modified Thrombolysis In Cerebral Infarction (mTICI) ≥2b.

Results

The first-pass successful reperfusion rate was higher in the BRETIS-TNK vs. control group (53.8% vs. 36%, p = 0.14), and the difference became statistically significant after propensity score matching (53.8% vs. 23.1%, p = 0.03). There was no difference in symptomatic intracranial hemorrhage between the BRETIS-TNK and control groups (7.7% vs. 10.0%, p = 0.92). There was a trend toward higher proportion of functional independence at 90 days in the BRETIS-TNK comparing with the control group (50% vs. 32%, p = 0.11).

Conclusion

This is the first study to report that intra-arterial TNK during the first pass of EVT seems safe and feasible in AIS-LVO patients.

Bridging intravenous thrombolysis in patients with atrial fibrillation

Background and purpose

40% of acute ischemic stroke patients treated by mechanical thrombectomy (MT) have a clinical history of atrial fibrillation (AF). The safety of bridging intravenous thrombolysis (IVT) (MT + IVT) is currently being discussed. We aimed to analyze the interaction between oral anticoagulation (OAC) status or AF with bridging IVT, regarding the occurrence of symptomatic intracranial hemorrhage (sICH) and functional outcome.

Materials and Methods

Multicentric observational cohort study (BEYOND-SWIFT registry) of consecutive patients undergoing MT between 2010 and 2018 (n = 2,941). Multinomial regression models were adjusted for prespecified baseline and plausible pathophysiological covariates identified on a univariate analysis to assess the association of AF and OAC status with sICH and good outcomes (90-day modified Rankin Scale score 0–2).

Results

In the total cohort (median age 74, 50.6% women), 1,347 (45.8%) patients had AF. Higher admission National Institutes of Health Stroke Scale (NIHSS) score (aOR 1.04 [95% 1.02–1.06], per point of increase) and prior medication with Vitamin K antagonists (VKA) (aOR 2.19 [95% 1.27–3.66]) were associated with sICH. Neither AF itself (aOR 0.71 [95% 0.41–1.24]) nor bridging IVT (aOR 1.08 [0.67–1.75]) were significantly associated with increased sICH. Receiving bridging IVT (aOR 1.61 [95% 1.24–2.11]) was associated with good 90-day outcome, with no interaction between AF and IVT (p = 0.92).

Conclusion

Bridging IVT appears to be a reasonable clinical option in selected patients with AF. Given the increased sICH risk in patients with VKA, subgroup analysis of the randomized controlled trials should analyze whether patients with VKA might benefit from withholding bridging IVT.

Registration

clinicaltrials.gov; Unique identifier: NCT03496064.

Endovascular thrombectomy versus standard medical treatment for stroke patients with acute basilar artery occlusion: a systematic review and meta-analysis

BACKGROUND

Whether endovascular thrombectomy (EVT) is superior to standard medical treatment (SMT) for stroke patients with acute basilar artery occlusion (BAO) is uncertain. This systematic review and meta-analysis aimed to compare the safety and efficacy of EVT with SMT for treating BAO patients.

METHODS

Papers were retrieved from PubMed, Embase, and the Cochrane Library databases. The primary outcome of this meta-analysis was favorable functional outcomes at 3 months (defined as a modified Rankin Scale (mRS) score of ≤3). A random effect model was used to calculate risk ratios (RR) with 95% confidence intervals (CIs) per outcome.

RESULTS

Five articles, including two randomized controlled trials (RCTs) and four observational cohort studies, comprising 1484 patients (1024 in the EVT group and 460 in the SMT group), were included in the meta-analysis. The pooled results demonstrated no significant differences between the EVT and SMT groups in achieving favorable functional outcomes at 3 months (RR=1.63, 95% CI 0.90, 2.96; p=0.11). However, patients in the EVT group had higher rates for symptomatic intracerebral hemorrhage (RR=6.22, 95% CI 2.06 to 18.76; p=0.001) but lower mortality at 3 months (RR=0.72, 95% CI 0.56 to 0.91; p=0.007) than patients in the SMT group.

CONCLUSION

Among patients with BAO, EVT and SMT did not differ significantly in achieving favorable functional outcomes at 3 months, but BAO patients treated with EVT might have lower mortality at 3 months. RCTs are warranted to further assess the efficacy and safety of EVT for BAO patients.

Net clinical benefit of anticoagulant therapy from a neurologist's perspective: A review

In this article the concept of "net clinical benefit" (NCB) is considered in the context of stroke, the role of direct oral anticoagulants in secondary prevention of cardioembolic stroke and NCB from their prescription. Practical aspects of NCB evaluation from the neurologist's point of view are presented, taking into account such factors as stroke duration and severity, features of neurological deficit (severity of residual limitations, dysphagia, motor disorders and risk of falls), neuroimaging characteristics of stroke (focal size and hemorrhagic transformation) and concomitant neurological diseases (epilepsy and dementia). In all these situations, the use of oral anticoagulants has a significant clinical benefit, which justifies the inadmissibility of refusal to prescribe them.