Intravenous Tissue Plasminogen Activator in Combination With Mechanical Thrombectomy: Clot Migration, Intracranial Bleeding, and the Impact of "Drip and Ship" on Effectiveness and Outcomes

Clot migration in patients treated with tenecteplase versus alteplase before mechanical thrombectomy

INTRODUCTION

This study aimed to describe and analyze the rate of clot migration of vessel thrombosis to distal segments in patients with acute ischemic stroke (AIS) who received intravenous thrombolysis (IVT) with tenecteplase (TNK) and alteplase (ALT) before mechanical thrombectomy (MT). In addition, we aimed to determine the relationship between thrombus migration and functional prognosis.

METHODS

This study followed the STROBE reporting guidelines. We performed a retrospective analysis of a series of patients from November 2017 to April 2023 with an AIS with thrombosis on CT imaging, treated with IVT (TNK or ALT, split into two distinct groups) prior to mechanical thrombectomy.

RESULTS

Two hundred and fifty-six patients with large vessel occlusion (LVO) were included. Ninety-six had received TNK. One hundred and sixty had received ALT. Of the 96 TNK patients, 25 experienced either complete recanalization (n = 3) or thrombus migration (n = 22). Of the 160 ALT patients, 20 experienced either complete recanalization (n = 6) or thrombus migration (n = 14). The difference being statistically substantial for the thrombus migration rate (OR = 3.61, 95% confidence interval: 1.63; 7.98). Migration to an irretrievable very distal segment occurred in four (4%) patients with TNK and in three patients (2%) with ALT (p > 0.05). Thrombus migration was not significantly associated to a different functional prognosis, measured through Rankin scale after 3 months (OR = 0.44, 95% confidence interval: 0.17; 1.12).

CONCLUSION

The use of TNK over ALT as a fibrinolytic agent is associated with a higher thrombus migration rate. The migration of thrombi to distal segments, which are theoretically less accessible for mechanical thrombectomy, did not result in worse clinical outcomes.

rtPA-loaded fucoidan polymer microbubbles for the targeted treatment of stroke

Systemic injection of thrombolytic drugs is the gold standard treatment for non-invasive blood clot resolution. The most serious risks associated with the intravenous injection of tissue plasminogen activator-like proteins are the bleeding complication and the dose related neurotoxicity. Indeed, the drug has to be injected in high concentrations due to its short half-life, the presence of its natural blood inhibitor (PAI-1) and the fast hepatic clearance (0.9 mg/kg in humans, 10 mg/kg in mouse models). Overall, there is a serious need for a dose-reduced targeted treatment to overcome these issues. We present in this article a new acoustic cavitation-based method for polymer MBs synthesis, three times faster than current hydrodynamic-cavitation method. The generated MBs are ultrasound responsive, stable and biocompatible. Their functionalization enabled the efficient and targeted treatment of stroke, without side effects. The stabilizing shell of the MBs is composed of Poly-Isobutyl Cyanoacrylate (PIBCA), copolymerized with fucoidan. Widely studied for its targeting properties, fucoidan exhibit a nanomolar affinity for activated endothelium and activated platelets (P-selectins). Secondly, the thrombolytic agent (rtPA) was loaded onto microbubbles (MBs) with a simple adsorption protocol. Hence, the present study validated the in vivo efficiency of rtPA-loaded Fuco MBs to be over 50 % more efficient than regular free rtPA injection for stroke resolution. In addition, the relative injected rtPA grafted onto targeting MBs was 1/10th of the standard effective dose (1 mg/kg in mouse). As a result, no hemorrhagic event, BBB leakage nor unexpected tissue distribution were observed.

The clinical utility of dual-energy CT in post-thrombectomy care: Part 1, predictors and outcomes of subarachnoid and intraparenchymal hemorrhage

OBJECTIVES

Dual-energy CT allows differentiation between blood and iodinated contrast. We aimed to determine predictors of subarachnoid and intraparenchymal hemorrhage on dual-energy CT performed immediately post-thrombectomy and the impact of these hemorrhages on 90-day outcomes.

MATERIALS AND METHODS

A retrospective analysis was performed on patients who underwent thrombectomy for anterior circulation large-vessel occlusion and subsequent dual-energy CT at a comprehensive stroke center from 2018-2021. The presence of contrast, subarachnoid hemorrhage, or intraparenchymal hemorrhage immediately post-thrombectomy was assessed by dual-energy CT. Univariable and multivariable analyses were performed to identify predictors of post-thrombectomy hemorrhages and 90-day outcomes. Patients with unknown 90-day mRS were excluded.

RESULTS

Of 196 patients, subarachnoid hemorrhage was seen in 17, and intraparenchymal hemorrhage in 23 on dual-energy CT performed immediately post-thrombectomy. On multivariable analysis, subarachnoid hemorrhage was predicted by stent retriever use in the M2 segment of MCA (OR,4.64;p=0.017;95%CI,1.49-14.35) and the number of thrombectomy passes (OR,1.79;p=0.019;95%CI,1.09-2.94;per an additional pass), while intraparenchymal hemorrhage was predicted by preprocedural non-contrast CT-based ASPECTS (OR,8.66;p=0.049;95%CI,0.92-81.55;per 1 score decrease) and preprocedural systolic blood pressure (OR,5.10;p=0.037;95%CI,1.04-24.93;per 10 mmHg increase). After adjusting for potential confounders, intraparenchymal hemorrhage was associated with worse functional outcomes (OR,0.25;p=0.021;95%CI,0.07-0.82) and mortality (OR,4.30;p=0.023,95%CI,1.20-15.36), while subarachnoid hemorrhage was associated with neither.

CONCLUSIONS

Intraparenchymal hemorrhage immediately post-thrombectomy was associated with worse functional outcomes and mortality and can be predicted by low ASPECTS and elevated preprocedural systolic blood pressure. Future studies focusing on management strategies for patients presenting with low ASPECTS or elevated blood pressure to prevent post-thrombectomy intraparenchymal hemorrhage are warranted.

In a hub-and-spoke network, spoke-administered thrombolysis reduces mechanical thrombectomy procedure time and number of passes

BACKGROUND

The utility of intravenous thrombolysis (IVT) prior to mechanical thrombectomy (MT) in large vessel occlusion stroke (LVO) is controversial. Some data suggest IVT increases MT technical difficulty. Within our hub-and-spoke telestroke network, we examined how spoke-administered IVT affected hub MT procedure time and pass number.

METHODS

Patients presenting to 25 spoke hospitals who were transferred to the hub and underwent MT from 2018 to 2020 were identified from a prospectively maintained database. MT procedure time, fluoroscopy time, and pass number were obtained from operative reports.

RESULTS

Of 107 patients, 48 received IVT at spokes. Baseline characteristics and NIHSS were similar. The last known well (LKW)-to-puncture time was shorter among IVT patients (4.3 ± 1.9 h vs. 10.5 ± 6.5 h, p < 0.0001). In patients that received IVT, mean MT procedure time was decreased by 18.8 min (50.5 ± 29.4 vs. 69.3 ± 46.7 min, p = 0.02) and mean fluoroscopy time was decreased by 11.3 min (21.7 ± 15.8 vs. 33.0 ± 30.9 min, p = 0.03). Furthermore, IVT-treated patients required fewer MT passes (median 1 pass [IQR 1.0, 1.80] vs. 2 passes [1.0, 2.3], p = 0.0002) and were more likely to achieve reperfusion in ≤2 passes (81.3% vs. 59.3%, p = 0.01). An increased proportion of IVT-treated patients achieved TICI 2b-3 reperfusion after MT (93.9% vs. 83.8%, p = 0.045). There were no associations between MT procedural characteristics and LKW-to-puncture time.

CONCLUSION

Within our network, hub MT following spoke-administered IVT was faster, required fewer passes, and achieved improved reperfusion. This suggests spoke-administered IVT does not impair MT, but instead may enhance it.

Prediction of Poor Outcome after Successful Thrombectomy in Patients with Severe Acute Ischemic Stroke: A Pilot Retrospective Study

Several baseline hematologic and metabolic laboratory parameters have been linked to acute ischemic stroke (AIS) clinical outcomes in patients who successfully recanalized. However, no study has directly investigated these relationships within the severe stroke subgroup. The goal of this study is to identify potential predictive clinical, lab, and radiographic biomarkers in patients who present with severe AIS due to large vessel occlusion and have been successfully treated with mechanical thrombectomy. This single-center, retrospective study included patients who experienced AIS secondary to large vessel occlusion with an initial NIHSS score ≥ 21 and were recanalized successfully with mechanical thrombectomy. Retrospectively, demographic, clinical, and radiologic data from electronic medical records were extracted, and laboratory baseline parameters were obtained from emergency department records. The clinical outcome was defined as the modified Rankin Scale (mRS) score at 90 days, which was dichotomized into favorable functional outcome (mRS 0-3) or unfavorable functional outcome (mRS 4-6). Multivariate logistic regression was used to build predictive models. A total of 53 patients were included. There were 26 patients in the favorable outcome group and 27 in the unfavorable outcome group. Age and platelet count (PC) were found to be predictors of unfavorable outcomes in the multivariate logistic regression analysis. The areas under the receiver operating characteristic (ROC) curve of models 1 (age only model), 2 (PC only model), and 3 (age and PC model) were 0.71, 0.68, and 0.79, respectively. This is the first study to reveal that elevated PC is an independent predictor of unfavorable outcomes in this specialized group.

What You Always Wanted to Know about Endovascular Therapy in Acute Ischemic Stroke but Never Dared to Ask: A Comprehensive Review

In 2015, mechanical thrombectomy (MT) in combination with intravenous thrombolysis was demonstrated to be superior to best medical treatment alone in patients with anterior circulation stroke. This finding resulted in an unprecedented boost in endovascular stroke therapy, and MT became widely available. MT was initially approved for patients presenting with large vessel occlusion in the anterior circulation (intracranial internal carotid artery or proximal middle cerebral artery) within a 6-hour time window. Eventually, it was shown to be beneficial in a broader group of patients, including those without known symptom-onset, wake-up stroke, or patients with posterior circulation stroke. Technical developments and the implementation of novel thrombectomy devices further facilitated endovascular recanalization for acute ischemic stroke. However, some aspects remain controversial. Is MT suitable for medium or very distal vessel occlusions? Should emergency stenting be performed for symptomatic stenosis or recurrent occlusion? How should patients with large vessel occlusion without disabling symptoms be treated? Do certain patients benefit from MT without intravenous thrombolysis? In the era of personalized decision-making, some of these questions require an individualized approach based on comorbidities, imaging criteria, and the severity or duration of symptoms. Despite its successful development in the past decade, endovascular stroke therapy will remain a challenging and fascinating field in the years to come. This review aims to provide an overview of patient selection, and the indications for and execution of MT in patients with acute ischemic stroke.

Trauma Communications Center Coordinated Severity-Based Stroke Triage: Protocol of a Hybrid Type 1 Effectiveness-Implementation Study

Background: Mechanical thrombectomy (MT) can improve the outcomes of patients with large vessel occlusion (LVO), but a minority of patients with LVO are treated and there are disparities in timely access to MT. In part, this is because in most regions, including Alabama, the emergency medical service (EMS) transports all patients with suspected stroke, regardless of severity, to the nearest stroke center. Consequently, patients with LVO may experience delayed arrival at stroke centers with MT capability and worse outcomes. Alabama's trauma communications center (TCC) coordinates EMS transport of trauma patients by trauma severity and regional hospital capability. Our aims are to develop a severity-based stroke triage (SBST) care model based on Alabama's trauma system, compare the effectiveness of this care pathway to current stroke triage in Alabama for improving broad, equitable, and timely access to MT, and explore stakeholder perceptions of the intervention's feasibility, appropriateness, and acceptability.

Methods: This is a hybrid type 1 effectiveness-implementation study with a multi-phase mixed methods sequential design and an embedded observational stepped wedge cluster trial. We will extend TCC guided stroke severity assessment to all EMS regions in Alabama; conduct stakeholder interviews and focus groups to aid in development of region and hospital specific prehospital and inter-facility stroke triage plans for patients with suspected LVO; implement a phased rollout of TCC Coordinated SBST across Alabama's six EMS regions; and conduct stakeholder surveys and interviews to assess context-specific perceptions of the intervention. The primary outcome is the change in proportion of prehospital stroke system patients with suspected LVO who are treated with MT before and after implementation of TCC Coordinated SBST. Secondary outcomes include change in broad public health impact before and after implementation and stakeholder perceptions of the intervention's feasibility, appropriateness, and acceptability using a mixed methods approach. With 1200 to 1300 total observations over 36 months, we have 80% power to detect a 15% improvement in the primary endpoint.

Discussion: This project, if successful, can demonstrate how the trauma system infrastructure can serve as the basis for a more integrated and effective system of emergency stroke care.

Effect of Occlusion Site on the Safety and Efficacy of Intravenous Alteplase Before Endovascular Thrombectomy: A Prespecified Subgroup Analysis of DIRECT-MT

BACKGROUND AND PURPOSE

Recent trials showed thrombectomy alone was comparable to bridging therapy in patients with anterior circulation large vessel occlusion eligible for both intravenous alteplase and endovascular thrombectomy. We performed this study to examine whether occlusion site modifies the effect of intravenous alteplase before thrombectomy.

METHODS

This is a prespecified subgroup analysis of a randomized trial evaluating risk and benefit of intravenous alteplase before thrombectomy (DIRECT-MT [Direct Intra-Arterial Thrombectomy in Order to Revascularize AIS Patients With Large Vessel Occlusion Efficiently in Chinese Tertiary Hospitals]). Among 658 randomized patients, 640 with baseline occlusion site information were included. The primary outcome was the score on the modified Rankin Scale at 90 days. Multivariable ordinal logistic regression analysis with an interaction term was used to estimate treatment effect modification by occlusion location (internal carotid artery versus M1 versus M2). We report the adjusted common odds ratio for a shift toward better outcome on the modified Rankin Scale after thrombectomy alone compared with combination treatment adjusted for age, the National Institutes of Health Stroke Scale score at baseline, the time from stroke onset to randomization, the modified Rankin Scale score before stroke onset, and collateral score per the DIRECT-MT statistical analysis plan.

RESULTS

The overall adjusted common odds ratio was 1.08 (95% CI, 0.82-1.43) with thrombectomy alone compared with combination treatment, and there was no significant treatment-by-occlusion site interaction (P=0.47). In subgroups based on occlusion location, we found the following adjusted common odds ratios: 0.99 (95% CI, 0.62-1.59) for internal carotid artery occlusions, 1.12 (95% CI, 0.77-1.64) for M1 occlusions, and 1.22 (95% CI, 0.53-2.79) for M2 occlusions. No treatment-by-occlusion site interactions were observed for dichotomized modified Rankin Scale distributions and successful reperfusion (extended thrombolysis in Cerebral Infarction score ≥2b) before thrombectomy. Differences in symptomatic hemorrhage rate were not significant between occlusion locations (internal carotid artery occlusion: 7.02% in bridging therapy versus 7.14% for thrombectomy alone, P=0.97; M1 occlusion: 5.06% versus 2.48%, P=0.22; M2 occlusion: 9.09% versus 4.76%; P=0.78).

CONCLUSIONS

In this prespecified subgroup of a randomized trial, we found no evidence that occlusion location can inform intravenous alteplase decisions in endovascular treatment eligible patients directly presenting at endovascular treatment capable centers. Future studies are needed to confirm our findings. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03469206.

Endovascular therapy for cerebral infarction due to Trousseau syndrome in a patient with non-small cell lung cancer

We describe a case of Trousseau's syndrome in a patient with lung carcinoma. A 69-year-old man presented with pleural effusion. Further evaluation revealed EGFR mutation-positive non-small cell carcinoma in the upper lobe with extensive lymph node, bone, and brain metastases. Administration of osimertinib, an EGFR tyrosine kinase inhibitor, resulted in partial tumor response, but caused osimertinib-induced pneumonitis 10 weeks later. Prednisolone restrained lung injury progression and was gradually tapered. However, he presented with impaired consciousness and right hemiplegia. Magnetic resonance imaging revealed a left middle cerebral artery M1 segment occlusion. D-dimer level was elevated to 19.5 μg/mL. In the absence of atherosclerotic or cardiogenic thrombi, these findings led to the diagnosis of Trousseau syndrome. Endovascular therapy, but not tissue plasminogen activator, improved his condition with no recurrences. These treatment strategies are crucial to restore function in patients with potentially disabling cerebral infarction due to Trousseau syndrome.

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Systemic anticoagulation for Trousseau syndrome generally has a poor prognosis.

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There is no established treatment for cancer-associated cerebral infarction.

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We performed endovascular therapy for cerebral infraction due to Trousseau syndrome.

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Endovascular therapy was effective for recanalization of the occluded artery.

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An NIHSS score of 0 was achieved with no recurrence.