Evolution of Stroke Thrombectomy Techniques to Optimize First-Pass Complete Reperfusion

Endovascular Thrombectomy for Acute Ischemic Stroke in Indonesia: Challenging and Strategic Planning

High rates of morbidity and mortality indicate that stroke is a major health concern. Unfortunately, the management of ischemic stroke is hindered by several obstacles, particularly in developing countries such as Indonesia, where the burden of morbidity and mortality remains high. In this literature review, we intend to conduct a thorough investigation and analysis of the obstacles to stroke thrombectomy in developing countries, with a focus on Indonesia. Even though numerous studies and recent advances in thrombectomy techniques have been developed, many centers around the world continue to struggle to implement them. The majority of these institutions are located in developing nations like Indonesia. It faces numerous obstacles, including a lack of public awareness, infrastructure, human resources, and financial difficulties. The absence of early education and large-scale campaigns contributes to the dearth of public awareness. Inadequate imaging facilities, prehospital and referral systems, as well as disparities in healthcare expenditure and accessibility, contribute to the absence of infrastructure. Inadequate numbers of neurointerventionists, neurologists, and neurosurgeons, as well as a disparate distribution of these professionals, contribute to human resource issues. Inadequate national insurance coverage, high import tariffs on medical devices, and the high cost of healthcare have a negative impact on the financial situation. We provide related strategies regarding the current situation in Indonesia based on the recent evidence and comparison with developed countries. Academic institutions, medical associations, and government agencies must collaborate to overcome these challenges.

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

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

Mechanical thrombectomy with a new intermediate balloon catheter combining the BGC and DAC features: Initial clinical experience with the iNedit device

INTRODUCTION

The iNedit balloon distal access catheter is a novel thrombectomy device. It has an inner diameter of 0.058″, proximal outer diameter of 2.13 mm, and distal outer diameter of 1.67mm. It is compatible with a 0.088″ guide catheter and includes a balloon located 5 cm from the catheter tip, enabling proximal flow restriction and combined therapy with stent retrievers. We investigate the appraisal of the use, safety, and efficacy of the iNedit catheter in the first-in-human study.

METHODS

In the preliminary cases that demanded training on the product previous to a multicentric study, prospective data were collected on 22 consecutive patients treated with the iNedit catheter to perform thrombectomy for acute ischemic stroke due to large vessel occlusion within 24 h. The outcome measures consisted of several evaluations of user experience rated on a 5-point scale ranging from 1 (bad) to 5 (excellent), as well as assessments of procedural safety outcomes such as artery perforation and arterial occlusion, procedural efficacy outcomes including first-pass effect (Thrombolysis In Cerebral Infarction [TICI] 2c/3) and final recanalization (TICI 2b/3), and clinical efficacy outcomes such as a 3-month 0-2 modified Rankin Scale (mRS).

RESULTS

The mean age was 72 ± 12 years old; median National Institute Health Stroke Scale was 17 (11-19). Sites of primary occlusion were: 2 internal carotid artery, 12 M1-MCA, 7 M2-MCA, and one P1. Median score evaluation of the appraisal of use was 4- IQR [4-5]. The median number of passes was 1 [IQR 1-2]. First pass complete recanalization rate was 50% and the final recanalization rate was 94.45%. No artery perforation and arterial occlusion. Good functional outcome mRS 0-2 was achieved in 50% of patients.

CONCLUSIONS

In this initial clinical experience, iNedit device achieved a high rate of first-pass effect and final recanalization rate with no safety concerns, thus favoring a high percentage of good clinical outcomes.

First pass effect in posterior circulation occlusions: Analysis from the CICAT registry

BACKGROUND

The first pass effect (FPE) is an independent predictor of functional independence in patients with large vessel occlusion in anterior circulation ischemic strokes. However, whether it predicts outcome in posterior circulation large vessel occlusion (PC-LVO) is uncertain. We aimed to study the frequency, characteristics, and predictors of FPE and its association with clinical outcomes in PC-LVO.

METHOD

We performed an analysis from the prospective CICAT Registry. All patients with PC-LVO who underwent endovascular therapy between January 2016 and January 2020 were included. A centrally assessed clinical follow-up was performed at 3 months by blinded investigators. FPE was defined as the achievement of modified Thrombolysis In Cerebral Infarction 3 in a single pass of the endovascular thrombectomy device, and multi-pass effect (MPE) if it was achieved in more than one pass. A multivariable analysis was performed to identify whether FPE is an independent predictor of functional independence defined as a modified Rankin Score of 0-2.

RESULTS

We analyzed data from 265 patients in who FPE was achieved in 105 (39.6%). Patients with FPE were more likely to achieve functional independence compared to the non-FPE group (52.4% vs 25.1%, p < .001) and the MPE group (52.4% vs 26.7%, p < .001). FPE was independently associated with functional independence (adjusted odds ratio (aOR): 2.10, 95% confidence interval (CI) 1.01-4.37) but MPE was not (aOR: 0.92, 95% CI 0.40-2.13). Independent predictors of FPE were the use of direct aspiration, embolic mechanism of stroke, and the absence of general anesthesia (GA) use.

CONCLUSIONS

FPE is an independent predictor of functional independence in PC-LVO and was associated with a significantly better outcome than MPE.

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.

Clot composition characterization using diffuse reflectance spectroscopy in acute ischemic stroke

Acute ischemic stroke caused by large vessel occlusion is treated with endovascular thrombectomy, but treatment failure may occur when clot composition and thrombectomy technique mismatch. In this proof-of-concept study, diffuse reflectance spectroscopy (DRS) is evaluated for identification of clot composition ex vivo. DRS spectra and histology were acquired from 45 clot units retrieved from 29 stroke patients. DRS spectra correlated to clot RBC content, R= 81, p < .001, and could discriminate between RBC-rich and fibrin-rich clots, p < 0.001. Sensitivity and specificity for detection of RBC-rich clots were 0.722 and 0.846 respectively. Applied in an intravascular device, DRS could potentially provide intraprocedural information on clot composition that could increase endovascular thrombectomy efficiency.

Aspects of ischemic stroke biomechanics derived using ex-vivo and in-vitro methods relating to mechanical thrombectomy

Establishing the underlying biomechanics of acute ischemic stroke (AIS) and its treatment is fundamental to developing more effective clinical treatments for one of society's most impactful diseases. Recent changes in AIS management, driven by clinical evidence of improved treatments, has already led to a rapid rate of innovation, which is likely to be sustained for many years to come. These unprecedented AIS triage and treatment innovations provide a great opportunity to better understand the disease. In this article we provide a perspective on the recreation of AIS in the laboratory to inform contemporary device design and procedural techniques in mechanical thrombectomy. Presentation of these findings, which have been used to solve the applied problem of designing mechanical thrombectomy devices, is intended to help inform the development of basic biomechanics solutions for AIS.

Combined Approach to Stroke Thrombectomy Using a Novel Short Flexible Aspiration Catheter with a Stent Retriever : Preliminary Clinical Experience

BACKGROUND

Large-bore aspiration catheters enabling greater flow rates and suction force for mechanical thrombectomy might improve outcomes in patients with stroke secondary to large-vessel occlusion. Complete or near-complete reperfusion after a single thrombectomy pass (first-pass effect) is associated with improved clinical outcomes. We assessed the efficacy and safety of novel MIVI Q™ aspiration catheters in combination with stent-retriever devices.

METHODS

We retrospectively analyzed demographics, procedure characteristics, and clinical data from consecutive patients with acute anterior large-vessel occlusion treated with a combined approach using MIVI Q™ aspiration catheters and stent retrievers. Reperfusion was defined according to the modified thrombolysis in cerebral infarction (mTICI) score. Clinical outcomes were measured by the National Institute of Health Stroke Scale (NIHSS) and modified Rankin scale (mRS) scores.

RESULTS

We included 52 patients (median age, 75 y IQR: 64-83); 31 (59.6%) women; 14 (26.9%) with terminal internal carotid artery occlusions, 26 (50%) middle cerebral artery (MCA) segment M1 occlusions, and 12 (23.1%) MCA segment M2 occlusions; median NIHSS score at admission was 19 (IQR: 13-22). After the first pass, 25 (48%) patients had mTICI ≥ 2c. At the end of the procedure, 47 (90.4%) had mTICI ≥ 2b and 35 (67.3%) had mTICI ≥ 2c. No serious device-related adverse events were observed. Symptomatic intracranial hemorrhage developed in 1 patient. Mean NIHSS score was 13 at 24 h and 5 at discharge. At 90 days, 24 (46.2%) patients were functionally independent (mRS 0-2).

CONCLUSION

This preliminary study found good efficacy and safety for MIVI Q™ aspiration catheters used in combination with stent-retriever devices.

Thrombolytic strategies for ischemic stroke in the thrombectomy era

Twenty-five years ago, intravenous thrombolysis has revolutionized the care of patients with acute ischemic stroke. Since 2015, randomized clinical trials have demonstrated that mechanical thrombectomy improves functional outcome in stroke patients over intravenous thrombolysis alone. More recently, three randomized clinical trials have suggested that mechanical thrombectomy alone is noninferior to a combined strategy with both intravenous thrombolysis and mechanical thrombectomy. In the present review, we will present the last clinical and preclinical studies on the use of thrombolysis in stroke patients in the modern thrombectomy era. At the cost of a potential increased risk of hemorrhagic transformation, thrombolysis may promote arterial recanalization before thrombectomy, improve the rate of successful recanalization after thrombectomy, and restore microcirculation patency downstream of the main thrombus. Besides, new thrombolytic strategies targeting tissue-type plasminogen activator resistant thrombi are being developed, which could strengthen the beneficial effects of thrombolysis without carrying additional pro-hemorrhagic effects. For instance, tenecteplase has shown improved rate of recanalization compared with tissue-type plasminogen activator (alteplase). Beyond fibrinolysis, DNA- and von Willebrand factor-targeted thrombolytic strategies have shown promising results in experimental models of ischemic stroke. New combined strategies, improved thrombolytics, and dedicated clinical trials in selected patients are eagerly awaited to further improve functional outcome in stroke.

Clot-based radiomics features predict first pass effect in acute ischemic stroke

PURPOSE

Our aim was to evaluate the performance of clot-based radiomics features (RFs) for predicting first pass effect (FPE) in patients with acute ischemic stroke (AIS). The secondary purpose was to search for any other variables associated with FPE.

MATERIALS AND METHODS

Patients who underwent mechanical thrombectomy (MT) for anterior circulation large vessel stroke in a single center were retrospectively reviewed. Patients were divided into two groups: FPE and non-FPE. Two observers extracted RFs from the clot on pretreatment noncontrast computed tomography (NCCT) images. Demographic, clinical, periprocedural, and RFs were compared between the groups and receiver operating characteristic (ROC) curves were constructed. Logistic regression analysis was used to determine the independent predictors of FPE.

RESULTS

Fifty-two patients (27 female, 25 male; mean age 64.50 ± 15.15) who were treated by stent retrievers as the first option were included in the study. FPE was achieved in 25 patients (25/52, 48.1%). Twelve RFs were significantly different between patients with FPE and non-FPE. The long-run low gray-level emphasis (odds ratio = 44.24, p = 0.003) and the zone percentage (odds ratio = 16.88, p = 0.017) were found as independent predictors of FPE. Female sex and a baseline ASPECT score of >8.5 were the other independent variables to predict FPE. The diagnostic accuracy to predict FPE was observed as 83% when using all independent predictors in our predictive model.

CONCLUSIONS

Clot-based RFs on NCCT may help to estimate the success of the intended outcome of MT in patients with AIS.

JET 7 XTRA Flex reperfusion catheter related complications during endovascular thrombectomy

Endovascular thrombectomy has revolutionized the management of acute ischemic stroke from emergent large vessel occlusion. Continued technological advancement in the field, as evidenced by successive introduction of large bore aspiration catheters with enhanced trackability and large inner diameter, has played a major role in achieving fast and robust recanalization and improved clinical outcome. Here, we present three patients with intraprocedural device malfunction related to the JET 7 XTRA Flex reperfusion catheter.