Mechanical Thrombectomy Devices Research Articles

Initial experience with a novel stent-based mechanical thrombectomy device for management of acute myocardial infarction cases with large thrombus burden.

Patients with acute myocardial infarction (AMI) and large thrombus burden (LTB) still represent a challenge. Afflicted patients have a high morbidity and mortality. Aspiration thrombectomy is often ineffective in those cases. Mechanical thrombectomy devices (MTDs), which are effective for management of ischemic strokes, were recently CE-approved for treatment of thrombotic coronary lesions. Real-world data about their performance in AMI cases with LTB are scarce. This study sought to summarize our early experience with a novel MTD device in this context. We analyzed consecutive patients from the prospective OPTIMISER registry (NCT04988672), who have been managed with the NeVa™ MTD (Vesalio, USA) for AMI with LTB at a tertiary cardiology facility. Outcomes of interest included, among others, periprocedural complications, target lesion failure (TLF), target lesion revascularization (TLR) and target vessel myocardial infarction (TV-MI). Overall, 15 patients underwent thrombectomy with the NeVa™ device. Thrombectomy was successfully performed in 14 (93%) patients. Final TIMI 3 flow was achieved in 13 (87%) patients, while 2 (13%) patients had TIMI 2 flow. We encountered no relevant periprocedural complications, especially no stroke, stent thrombosis or vessel closure. After a mean follow-up time of 26 ± 2.9months, 1 (7%) patient presented with TLR due to stent thrombosis (10months after treatment with the MTD and stenting). In AMI patients with LTB, the deployment of the novel NeVa™ MTD seems efficient and safe. Further randomized trials are warranted to assess whether the use of the NeVa™ device in cases with LTB improves procedural and clinical outcomes.

Fubuki XF Long Sheath guide catheter use in neuroendovascular procedures: Institutional experience in 60 cases.

Endovascular treatment devices require compatible guide catheters to navigate complex vessels and anatomy. The Fubuki XF Long Sheath guide catheter (Fubuki XF) was developed with a 0.090-inch internal diameter with hydrophilic coating, an atraumatic rounded tip, and enhanced trackability and support with gradual shaft transition zones. We retrospectively analyzed a prospectively maintained database of neuroendovascular patients treated using Fubuki XF at our center (July 2022─May 2023). Baseline/procedural characteristics were collected. Outcomes of interest included technical success (procedure completion with Fubuki XF without alternative guide catheter use) and peri-procedural complications. This study included 60 patients (43.3% [26/60] female; mean age: 69.6 ± 9.7) presenting with stenosis (45.0% [27/60]), unruptured aneurysms (31.7% [19/60]), ruptured aneurysm (1.7% [1/60]), arteriovenous fistula (5.0% [3/60]), arteriovenous malformation (3.3% [2/60]), chronic subdural hematoma (3.3% [2/60]), stroke/emboli (6.7% [4/60]), vasospasm (1.7% [1/60]), or carotid web (5.0% [1/60]). Fubuki XF was used to deliver endovascular treatment devices for stenting (43.3% [26/60]), flow diversion (23.3% [14/60]), embolization (11.7% [7/60]), coiling (10.0% [6/60]), balloon angioplasty (10.0% [6/60]), and mechanical thrombectomy (1.7% [1/60]). The Fubuki XF tip was placed in the internal carotid artery in 38.3% (23/60) of cases. Technical success was achieved in all cases. One V1 non-flow-limiting dissection (not related to Fubuki XF) and one failed closure occurred (1.7% [1/60] each). No iatrogenic strokes or intraprocedural ruptures occurred. We used Fubuki XF to safely and effectively deliver a variety of compatible neuroendovascular devices. Fubuki XF was stable in all cases and locations, and there were no device-related complications or dissections.

A cross-sectional study of outcomes for patients undergoing mechanical thrombectomy for pulmonary embolism during 2018-2022: Insights from the PINC AI Healthcare Database.

Mechanical thrombectomy (MT) treatments for pulmonary embolism (PE) have yet to be compared directly. We aimed to determine if patient outcomes varied following treatment of PE with different MT devices. All PE encounters with an index treatment of MT between January 2018 and March 2022 were analyzed for in-hospital mortality, discharge to home, and 30-day readmission outcomes in the PINC AI™ Healthcare Database. MT devices used in each encounter were extracted from hospital charge description free-text fields using keyword text and fuzzy matching. Unadjusted and adjusted logistic regression was used to model outcomes by device. A total of 5893 encounters were identified using MT as the sole index PE treatment and 1812 using MT with another treatment. Of these, 41% had insufficient information to identify the devices used (unspecified MT), 33% used the FlowTriever System (large-bore volume-controlled aspiration MT), 23% the Indigo System (continuous aspiration MT), and 3% some other MT. Large-bore volume-controlled aspiration MT was used with other treatments 13% of the time compared with 23% and 39% for unspecified MT and continuous aspiration MT, respectively. Adjusted logistic regression modeling revealed the odds of in-hospital mortality were significantly higher for patients treated with unspecified MT ([OR] = 1.42, 95% confidence interval [CI]: [1.10-1.83], p = 0.008) or continuous aspiration MT (OR = 1.63, 95% CI: [1.21-2.19], p = 0.001) compared with large-bore volume-controlled aspiration MT. Discharge to home was significantly lower in these same groups (OR = 0.84, 95% CI: [0.73-0.96], p = 0.01, and OR = 0.63, 95% CI: [0.53-0.74], p < 0.001, respectively), but readmission risks at 30 days were comparable (OR = 1.08, 95% CI: [0.84-1.38], p = 0.56, and OR = 1.20, 95% CI: [0.89-1.62], p = 0.24, respectively). PE outcomes and treatment patterns differ significantly based on the type of MT utilized. Clinical studies directly comparing MT treatments are needed to further understand optimal treatment of PE.

Utilizing RNA sequencing to identify gene expression markers of stroke-causing thrombi origin: A pilot study

IntroductionStroke embolic source have an unknown origin in 30-40% of cases. Mechanical thrombectomy for acute large vessel occlusion stroke has provided us with a method to directly retrieve the thrombi from patients for analysis. By collecting stroke-causing thrombi from known sources, we can then use high-throughput RNA sequencing (RNAseq) technology to directly measure the gene expression signatures of these clots. This may allow us to identify genetic markers to predict the cause of cryptogenic embolism. MethodsThis is a prospective study in which RNAseq was used to analyze cerebral thrombi retrieved by mechanical thrombectomy devices in acute ischemic stroke patients. Samples were separated into two groups based on known stroke thrombus etiology, including Carotid group (patients with ipsilateral >70% carotid stenosis) and Atrial fibrillation (AF) group (patients with atrial fibrillation). Gene expression was compared by RNAseq analysis between the groups. ResultsFrom October 2016 to September 2017, 8 thrombi (4 in Carotid group, 4 in Afib group) were included in this study. There were 131 genes that were significantly up- or down-regulated between the two groups defined as a false discovery rate ≤ 0.05 and a fold change ≥ 2. Twenty-six genes were selected as candidate gene biomarkers based on the criteria in the methods section. Candidate genes HSPA1B, which encodes a heatshock protein, and GPRC5B, which encodes a G-protein, showed the greatest fold differences in expression between the two groups. ConclusionThis study has shown that RNA sequencing of acute ischemic stroke thrombi is feasible and indentified potential novel biomarkers for identifying stroke-causing thrombi origin, especially in cryptogenic stroke.

Initial experience with the ambulatory management of acute iliofemoral deep vein thrombosis with May-Thurner syndrome with percutaneous mechanical thrombectomy, angioplasty and stenting

ObjectivePatients undergoing intervention for acute iliofemoral deep vein thrombosis (IFDVT) with May-Thurner syndrome (MTS) typically require inpatient (IP) hospitalization for initial treatment with anticoagulation and management with pharmacomechanical thrombectomy. Direct oral anticoagulants and percutaneous mechanical thrombectomy (PMT) devices offer the opportunity for outpatient (OP) management. We describe our approach with these patients. MethodsPatients receiving intervention for acute IFDVT from January 2020 through October 2022 were retrospectively reviewed. Patients undergoing unilateral thrombectomy, venous angioplasty, and stenting for IFDVT with MTS comprised the study population and were divided into two groups: (1) patients admitted to the hospital and treated as IPs and (2) patients who underwent therapy as OPs. The two groups were compared regarding demographics, risk factors, procedural success, complications, and follow-up. ResultsA total of 92 patients were treated for IFDVT with thrombectomy, angioplasty, and stenting of whom 58 comprised the IP group and 34 the OP group. All 92 patients underwent PMT using the Inari ClotTriever (Inari Medical), intravascular ultrasound, angioplasty, and stenting with 100% technical success. Three patients in the IP group required adjuvant thrombolysis. There was no difference in primary patency of the treated IFDVT segment at 12 months between the two groups (IP, 73.5%; OP, 86.7%; P = .21, log-rank test). ConclusionsPatients with acute IFDVT and MTS deemed appropriate for thrombectomy and iliac revascularization can be managed with initiation of ambulatory direct oral anticoagulant therapy and subsequent return for ambulatory PMT, angioplasty, and stenting. This approach avoids the expense of IP care and allows for effective use of resources at a time when staffing and supply chain shortages have led to inefficiencies in the provision of IP care for nonemergent conditions.

Variation in Vessel Size and Angiographic Outcomes Following Stent‐Retriever Thrombectomy in Acute Ischemic Stroke: STRATIS Registry

Background Mechanical thrombectomy is established for large‐vessel occlusions in acute ischemic stroke, but the potential role in distal vessel occlusions of medium arteries is less well established. Such medium or distal arterial segments have not been assessed with respect to thrombectomy devices used during endovascular therapy. We conducted an analysis of arterial size, segmental anatomy, and stent‐retriever device performance with respect to vessel size during thrombectomy. Methods The STRATIS registry angiography core laboratory adjudicated the exact location of the occlusion, proximal, and distal device deployment, relationship to arterial bifurcations, and anatomic nomenclature. Arterial diameters were measured at all these sites. Statistical analyses examined the relationship between vessel and stent size, and arterial recanalization using expanded Thrombolysis in Cerebral Infarction reperfusion score. Results Overall, 665 patients with stroke were included following thrombectomy using various Solitaire device sizes, including Solitaire 4×40, Solitaire 6×30, Solitaire 4×20, Solitaire 6×20, and Solitaire 4×15. Arterial diameter at the occlusion site was a median of 2.17 mm (interquartile range [IQR], 1.88–2.60 mm) in the distal M1, 1.67 mm (IQR, 1.47–2.06 mm) in the proximal M2 middle cerebral artery, 1.50 mm (IQR, 1.15–1.61 mm) in the distal M2 middle cerebral artery, 1.24 mm (IQR, 1.11–1.24 mm) in the M3 middle cerebral artery, and 1.88 mm (IQR, 1.49–1.94 mm) in the P1 posterior cerebral artery. Expanded Thrombolysis in Cerebral Infarction 2b to 3 reperfusion was achieved in all M3 or P1 segment occlusions. The rate of first‐pass recanalization was significantly higher in patients with medium (0.75–2 mm) versus large (&gt;2 mm) vessel occlusion (69.5% versus 57.1%; P = 0.003). Conclusion Considerable overlap was noted between arterial sizes at occlusion sites carrying different segmental arterial nomenclature or vessel names. Substantial reperfusion may be achieved with currently available mechanical thrombectomy devices in medium arteries.

Abstract TP197: Impact of First-Pass Effect on Clinical Outcomes in Stroke Patients With Low Aspects

Introduction: The first-pass effect (FPE), defined as a complete or near-complete recanalization after a single pass of a mechanical thrombectomy (MT) device, has been linked to favorable clinical outcomes. However, its effectiveness in acute ischemic stroke (AIS) patients with low ASPECTS (Alberta Stroke Program Early CT Score 2-5) has not been validated. Method: We utilized data from STAR, a multicenter database of 84 centers worldwide, to conduct a retrospective, cohort study on patients who underwent MT for internal carotid artery (ICA) or M1 occlusion presenting with ASPECTS 2-5. We compared the outcomes of patients who achieved FPE (successful recanalization with an mTICI score of 2c or higher in one pass) to those who did not. The primary outcome was a 90-day favorable outcome, defined as mRS 0-3. Secondary outcomes included any intracranial hemorrhage (ICH), symptomatic ICH (sICH), and 90-day mortality. Results: Out of 10,229 patients in the STAR database, 250 patients met our inclusion criteria. Among those, 60 (24%) achieved FPE. There were no significant differences between the two groups in baseline, imaging, and procedural characteristics. FPE was significantly associated with higher odds of 90-day mRS 0-3 (adjusted odds ratio (aOR): 2.17, 95% confidence interval (CI): 1.04 - 4.20; P-value: 0.04) and lower rates of ICH (OR: 0.49, 95% CI: 0.25 - 0.93, P-value: 0.03). However, there was no significant difference in sICH rates (OR: 0.84, 95% CI: 0.31 - 2.04, P-value: 0.70). Conclusion: Achieving FPE in AIS stroke patients with low ASPECTS was associated with significantly higher rates of good functional outcomes and lower rates of ICH.

The emerging role of mechanical thrombectomy in acute DVT management.

Catheter directed thrombolysis (CDT) and pharmacomechanical thrombectomy in various technical combinations have been the main driver of acute deep venous interventions for over a decade. While the majority of high-level evidence was based on it, CDT requires longer procedural care and is associated to a small but not negligible bleeding risk. Contemporary DVT intervention, following the paradigm shift in myocardial infarction and stroke management, has steadily migrated towards minimizing or eliminating thrombolytics due to the introduction of mechanical/aspiration thrombectomy. Mechanical thrombectomy (MT) devices are undoubtedly improving our ability to remove thrombus more efficiently in a single session without the adverse events and complex logistics related to the use of thrombolytics.

Multimodal Approach for the Treatment of Extensive Bilateral Iliofemoral Deep Vein Thrombosis

Abstract Iliofemoral vein thrombosis is the primary cause of deep vein thrombosis (DVTs) in the lower extremities in around 25% of the cases. Restoration of venous outflow is the primary goal in the management of DVT which can be achieved by combined endovascular techniques such as balloon venoplasty and/or stenting, thrombectomy, and pharmacomechanical thrombolysis. At presently, percutaneous mechanical thrombectomy (PMT) devices, such as rheolytic thrombectomy device, are replacing conventional approaches for clot removal. Although the use of rheolytic thrombectomy device for DVT is associated with the risk of intravascular hemolysis, we report a safe and successful use of multimodal approach using rheolytic thrombolytic device for the management of a case of bilateral iliofemoral DVT. In our study, we noticed early relief in pain and reduced lower limb edema in a week with a reduced dose of thrombolytic agent and hospital stay in a 44-year-old male who was admitted with bilateral extensive iliofemoral DVT using a multimodal approach.

The paradigm shift in treatment of severe venous thromboembolism.

Pulmonary embolism (PE) is the third leading cause of cardiovascular death and the main cause of preventable in-hospital death in the world. The PERT® (Pulmonary Embolism Response Team) concept involves multidisciplinary diagnosis and immediate treatment. Deep venous thrombosis (DVT) is the initial cause of most cases of PE and is responsible for complications such as chronic thromboembolic recurrence, postthrombotic syndrome, and chronic thromboembolic pulmonary hypertension. An aggressive approach to severe cases of iliofemoral DVT similar to the PERT® system can not only reduce the immediate risk of PE and death but can also reduce later sequelae. New percutaneous techniques and mechanical thrombectomy devices for venous thromboembolism (VTE) have shown encouraging clinical results. We propose the development of an expanded concept of rapid response to VTE, which involves not only PE (PERT®) but also severe cases of DVT: the Venous Thromboembolism Response Team (VTERT®).

Single-Session Thrombectomy without Thrombolysis for Iliofemoral Deep Vein Thrombosis: A Single-Center Experience of ClotTriever with Evaluation of Predictors for Reocclusion

Abstract Objective The aim of this study was to determine the effectiveness of a mechanical thrombectomy device in treating iliofemoral deep vein thrombosis (DVT) without thrombolysis and factors associated with post-thrombectomy occlusion. Methods A single-institution retrospective study of consecutive patients who underwent mechanical thrombectomy for iliofemoral DVT using the Inari ClotTriever device was performed from August 2019 to July 2022 without thrombolysis or aspiration. Pre- and post-thrombectomy modified Marder score, symptomatic relief, and other baseline characteristics were evaluated. Occlusion rate was evaluated by clinical symptoms and imaging studies during follow-up. Occlusion-free survival (OFS) was calculated. Factors associated with OFS were evaluated with log-rank tests and cox-proportional hazard ratio model. Procedure-related complications were reported. Results Among 32 included patients and 45 limbs, the mean Marder score decreased from 17.5 ± 8.1 to 0.13 ± 0.89 after thrombectomy. Stenting was needed in 13 patients (40.6%). No procedure-related major complication was observed postprocedurally. At initial follow-up, symptomatic improvement and occlusion-free patency were achieved in 80.0 and 72.2%, respectively. Poor venous inflow on post-thrombectomy venogram (p &lt; 0.05) was associated with early occlusion. Suboptimal use of post-thrombectomy anticoagulation (n = 7) was the only independent predictor of clinical and radiological OFS (p = 0.042). Conclusion Mechanical thrombectomy with ClotTriever is safe and effective in the treatment of acute and/or subacute iliofemoral DVT and can mitigate the need for thrombolytic therapy. Poor venous inflow on post-thrombectomy venogram and suboptimal use of anticoagulation were associated with early reocclusion.

FlowTriever System for Pulmonary Embolism: A Review of Clinical Evidence.

Pulmonary embolism (PE) is a significant cause of cardiovascular mortality, and its incidence has been increasing due to the growing aging population. Systemic or catheter-directed thrombolytic treatment for PE has an increased risk of bleeding that may offset the benefit in some patients. Mechanical thrombectomy devices such as the FlowTriever System are designed to resolve vascular occlusion and correct ventilation-perfusion mismatch without the need for thrombolytic drugs. This review covers the FlowTriever system, clinical data from the FlowTriever Pulmonary Embolectomy Clinical Study, FlowTriever for Acute Massive Pulmonary Embolism, and FlowTriever All-comer Registry for Patient Safety and Hemodynamics trials, and real-world experiences, demonstrating its safety and effectiveness in treating intermediate-risk and high-risk PE. Additionally, we explore off-label uses of the FlowTriever System for various large vessel thromboses.

Abstract 211: Comparing Early and Late Window 3mm Trevo Stent Retriever Performance in Medium Vessel Occlusion Thrombectomy

Introduction Endovascular thrombectomy has been shown to be beneficial for select patients with medium vessel occlusion ischemic strokes. Newer mechanical thrombectomy devices have designs to facilitate navigation of the medium and distal cerebrovasculature. In this single‐center study, we aim to compare the performance of 3mm Trevo NXT stent retrievers (Stryker, Kalamazoo, MI) for medium vessel occlusion mechanical thrombectomy for patients treated within either the early (&lt;6 hour) or late (&gt;6 hour) treatment window. Methods A retrospective review was conducted of acute ischemic stroke patients with medium vessel occlusions (i.e., M2‐M4, ACA, and PCA) who underwent thrombectomy over 5 years (2018‐2022) at a single comprehensive stroke center. Classification into early or late window was defined as time from last known well to groin puncture less than 6 hours or greater than 6 hours, respectively. Primary efficacy outcome included successful recanalization (modified thrombolysis in cerebral infarction [mTICI]&gt;=2B) using 3mm Trevo NXT on either first pass or rescue pass (i.e., after initial pass failure with another device). Primary safety outcome is rate of complications associated with the stent retriever. Primary clinical outcome was National Institutes of Health Stroke Scale (NIHSS) shift between admission and discharge. Results Of 81 patients with medium vessel occlusion ischemic strokes, 38 patients (44.7% female, median age of 73.5 years [IQR 66‐82], median initial NIHSS 13 [IQR 8‐23]) underwent thrombectomy with 3mm Trevo NXT. Stent retriever‐assisted aspiration (versus stent retriever only) was performed in 31/38 (81.6%) patients. Successful recanalization with stent retriever was achieved in 28/38 (73.7%) of patients. There was no significant difference in rate of recanalization between early and late window thrombectomy (16/22 [72.7%] early window vs. 12/16 [75%] late window, p=0.8752). The lack of significant difference in recanalization rate was consistent with stent retriever use during first pass (11/14 [78.6%] early window vs. 9/10 [90%] late window, p=0.6146) and as rescue (5/8 [62.5%] early window vs. 3/6 [50%] late window, p=0.6400). There was no significant difference in the rate of stent retriever complications between early and late windows (1/16 [6.3%] early vs. 0/22 [0%] late, p=0.4211). There was no significant difference in median NIHSS shift from admission to discharge ( ‐6 [IQR ‐16 ‐ 9] early window vs. ‐3 [IQR ‐5 ‐ 4] late window, p=0.3666). Conclusion In both early and late window medium vessel occlusion thrombectomy, the 3mm Trevo NXT as first line and rescue intervention performs comparably and adequately. Future multicenter studies will further characterize novel stent retriever performance in medium vessel occlusion thrombectomies.

Novel Percutaneous Mechanical Thrombectomy Device for Treating Upper Extremity Deep Vein Thrombosis in Patient With Paget-Schroetter Syndrome.

Paget-Schroetter Syndrome (PSS) is a form of upper extremity deep vein thrombosis (DVT) caused by the external compression of the subclavian vein at the thoracic outlet. Here we describe a complex PSS case in a 43-year-old female who experienced multiple recurrent DVTs and a right-sided hemothorax following two continuous aspiration thrombectomy procedures and a first rib resection. Rapid and complete symptom resolution was achieved with the InThrill Thrombectomy System (Inari Medical), a novel, thrombolytic-free, percutaneous mechanical thrombectomy device that removed all recurrent acute and subacute thrombus in a single session without significant blood loss.

Single center experience using 3 mm trevo stent retrievers in medium vessel occlusion thrombectomy.

Endovascular mechanical thrombectomy has been shown to benefit select patients with acute ischemic stroke caused by medium vessel occlusion, aided by recent advancements in endovascular mechanical thrombectomy devices that facilitate navigation through narrower vasculature. In this study, we aim to evaluate the safety and efficacy of using the 3 mm Trevo NXT stent retriever (Stryker, Kalamazoo, MI) for endovascular mechanical thrombectomy in patients with acute ischemic stroke caused by medium vessel occlusion. From our single-center registry, we performed a retrospective review of all acute ischemic stroke patients from 2018 to 2022 who underwent endovascular mechanical thrombectomy for medium vessel occlusion with a 3 mm Trevo NXT. We examined efficacy outcomes (modified thrombolysis in cerebral infarction and puncture-to-revascularization time), clinical outcomes (National Institutes of Health Stroke Scale), and procedural complication rate. Between 2018 and 2022, 44 patients (52.2% female, mean age 71.1 years, median National Institutes of Health Stroke Scale of 15 [8-22.8]) met our inclusion criteria. The 3 mm Trevo NXT was used in the first pass in 56.9% of individuals, with 72.4% achieving successful recanalization (modified thrombolysis in cerebral infarction ≥ 2B). The 3 mm Trevo NXT was used as "rescue" after initial revascularization failure in 43.1% of individuals, achieving successful recanalization in 60.0% of passes. Acute complications were reported in 2.4% of cases. Median National Institutes of Health Stroke Scale at 24 h after intervention was 12 (4-20.8). Our results suggest that endovascular mechanical thrombectomy using the 3 mm Trevo NXT is a safe and effective treatment option for medium vessel occlusion. The utility of novel stent retrievers in the treatment of medium vessel occlusion should be further explored in future multicenter studies.

The balloon occlusion sheath for stroke (BOSS) balloon guide catheter for stroke intervention: Safety and technical success.

We describe the first-in-human experience using the Balloon Occlusion Stroke Sheath (BOSSTM) balloon-guide catheter to perform stroke thrombectomy in 50 consecutive patients enrolled in the Flow Arrest Safety and Technical success with balloon-guide catheters trial. This aspiration system includes a novel 9.4F balloon-guide catheter conduit for the insertion and guidance of catheters with a balloon providing temporary flow arrest. The Flow Arrest Safety and Technical success with balloon-guide catheter trial is a single-arm, prospective, multi-center, non-randomized, observational registry evaluating the use of the market-released BOSSTM balloon-guide catheter in adult patients diagnosed with an acute ischemic stroke attributable to large vessel occlusion. The purpose of the current trial was to assess the safety and technical success associated with the use of the BOSSTM balloon-guide catheter. Fifty patients met inclusion criteria with a mean baseline National Institutes of Health Stroke Scale (NIHSS) of 16. Treatment devices, including aspiration and stent retriever devices, were used in a total of 88 passes. The BOSSTM balloon-guide catheter was compatible with all stroke thrombectomy treatment devices used in 98% (49/50) of procedures. Balloon inflation and flow arrest were achieved in 100% (50/50) and 98% (49/50) of cases, respectively. Balloon deflation and retraction were observed in 100% (50/50) of cases. Successful reperfusion (modified thrombolysis in cerebral infarction score > 2b) was achieved in 100% of cases with single-pass reperfusion achieved in 62% (31/50) of cases. The BOSSTM balloon-guide catheter is a safe and technically effective adjunctive device for mechanical thrombectomy of acute ischemic stroke due to large vessel occlusion.

Immediate and 90-Day Clinical Outcome of Patients with Acute Stroke Treated with the NeVa-Vesalio Mechanical Thrombectomy Device: A Retrospective Case Series

The NeVaTM stent-retriever is a newly designed mechanical thrombectomy device for the treatment of acute ischemic stroke caused by large vessel occlusion. We investigate the procedural characteristics and patients' clinical outcome at discharge and at 90 days of follow-up. We retrospectively reviewed a cohort of 75 patients (median age: 74 years) treated with the NeVaTM device for acute large vessel occlusion stroke. Per pass modified Treatment in Cerebral Infarction (mTICI) scores, procedural complications and clinical outcome parameters including National Institute of Health Stroke Scale (NIHSS), modified Rankin Scale (mRS) and mortality were analysed, based on patients' electronic medical records. Complete first pass effect was observed in 24 (32%) patients. Vasospasm, repeated re-thrombosis, failure to advance the NeVaTM device through the microcatheter and symptomatic intracranial hemorrhage were observed in n=2, n=1, n=1 and n=2 patient(s) respectively. The rate of complete (mTICI 2c-3) reperfusion were achieved in n=61 (81,33%) patients with a median number of 2 passes (1; 3). Median NIHSS on admission, after 24 hours and after 5-10 days or at discharge were of 19 (15; 23), 11 (4; 19) and 3 (2; 13.5) respectively. The number of patients with a functional mRS score (mRS score 0-2) at 90 days of follow-up was n=29 (39%) CONCLUSION: Endovascular stroke management with use of the Neva-Vesalio stent-retriever may be associated with a 90 days functional mRS score in nearly 40% of treated patients.

A novel method for preparing clot analogs under dynamic vortical flow for testing mechanical thrombectomy devices.

Clot analogs are essential in animal and in vitro experiments on mechanical thrombectomy devices for treating acute ischemic stroke. Clot analogs should be capable of reproducing a variety of arterial clots observed in clinical practice in terms of histological composition and mechanical properties. Bovine blood with added thrombin was stirred in a beaker so that clots could be formed under the condition of dynamic vortical flow. Static clots were also prepared without stirring, and the properties of the static clots and dynamic clots were compared. Histological and scanning electron microscopy experiments were performed. Compression and relaxation tests were performed to evaluate the mechanical properties of the two types of clots. Thromboembolism and thrombectomy tests were conducted in an in vitro circulation model. Compared to the static clots, the dynamic clots prepared under vortical flow displayed a higher fibrin content, and their fibrin network was denser and sturdier than that of the static clots. The stiffness of the dynamic clots was significantly higher than that of the static clots. The stress of both types of clots could decay quickly under large sustained strain. The static clots could break at the bifurcation in the vascular model, while the dynamic clots could be firmly stuck in the vascular model. Dynamic clots generated in dynamic vortical flow differ significantly from static clots in terms of their composition and mechanical properties, which may be beneficial information for preclinical research on mechanical thrombectomy devices.

Improved catheter delivery for aspiration thrombectomy using Tenzing 7 ledge reducing catheter and FreeClimb 70.

Previous comparative mechanical thrombectomy device trials reported a substantial crossover rate from first-line aspiration to stent-retriever thrombectomy. A specialized delivery catheter may help track large-bore aspiration catheters to target occlusions. We report our multicenter experience of aspiration thrombectomy of intracranial large vessel occlusions using the FreeClimbTM 70 and Tenzing® 7 delivery catheter (Route 92, San Mateo, CA). After local Institutional Review Board approval, we retrospectively reviewed the clinical, procedural, and imaging data of patients who underwent mechanical thrombectomy with the FreeClimb 70 and Tenzing 7. FreeClimb 70 was successfully delivered using Tenzing 7 to target occlusion in 30/30 (100%) patients (18 M1, 6 M2, 4 ICA-terminus, and 2 basilar artery occlusions), without the use of a stent-retriever for anchoring. In 21/30 (70%) cases, a leading microwire was not needed to advance the Tenzing 7 to the target. Median (interquartile range) time from groin puncture to first pass was 12 (interquartile range 8-15) minutes. Overall first pass effect, or first pass effect (modified thrombolysis in cerebral ischemia 2C-3), was achieved 16/30 (53%). For M1 occlusions, first pass effect was 11/18 (61%). Successful reperfusion (modified thrombolysis in cerebral ischemia ≥ 2B) was achieved in 29/30 (97%) cases after a median of 1 pass (interquartile range 1-3). Median groin puncture to reperfusion time was 16 (interquartile range 12-26) minutes. There were no procedural complications or symptomatic intracranial hemorrhage. Average improvement in National Institutes of Health Stroke Scale at discharge was 6.6 ± 7.1. There were three patient deaths (renal failure, respiratory failure, and comfort care). Initial data support the use of Tenzing 7 with FreeClimb 70 catheter for reliable access to rapid, effective, and safe aspiration thrombectomy of large vessel occlusions.

Management of Thrombosed Dialysis Access Circuits.

Thrombotic occlusion of autologous arteriovenous fistulas or synthetic arteriovenous grafts is a serious adverse event in hemodialysis patients and declotting should be performed before next hemodialysis session, in order to avoid a central venous catheter. Various techniques exist to declot a thrombosed vascular access, including open surgical thrombectomy, catheter-directed thrombolysis and use of different types of percutaneous thrombo-aspiration catheters and mechanical thrombectomy devices. These devices can be categorized as devices with direct wall contact and hydrodynamic devices without direct wall contact. Technical and early clinical outcome results of percutaneous hemodialysis declotting are high and ranging between 70 and 100%; late clinical patency results are much lower related to restenosis or re-thrombosis; these patency results are higher for autologous arteriovenous fistulas compared to synthetic arteriovenous grafts and mainly depend on the combined efficacy of successful thrombectomy and durable treatment of the underlying stenoses, associated with the acute thrombosis.