The economic impact associated with stent retriever selection for the treatment of acute ischemic stroke: a cost-effectiveness analysis of MASTRO I data from a Chinese healthcare system perspective.

Aim: The aim of this analysis was to assess the cost-effectiveness of the EmboTrap® Revascularization Device compared with the Solitaire™ Revascularization Device and Trevo® Retriever for the treatment of acute ischemic stroke (AIS) from the perspective of the Chinese healthcare system. Methods: According to MASTRO I, a recent living systematic literature review and meta-analysis, mechanical thrombectomy (MT) with EmboTrap in the treatment of AIS resulted in better functional outcomes compared with the use of Solitaire or Trevo. Based on the proportion of patients that achieved 90-day modified Rankin Scale (mRS) scores of 0-2, 3-5 and 6 reported in MASTRO I, a combined 90-day short-term decision tree and Markov model with a 10-year time horizon was used to compare the cost-effectiveness of the three devices. The primary outcome was the incremental cost-effectiveness ratio (ICER), representing the incremental cost (in 2022 Chinese Yuan [CNY]) per incremental quality-adjusted life-year (QALY). The ICERs were compared against willingness-to-pay (WTP) thresholds of 1, 1.5 and 3-times the 2022 national gross domestic product (GDP) per capita in China. Results: Treatment with EmboTrap resulted in total QALYs of 3.28 and total costs of 110,058 CNY per patient. Treatment with Trevo resulted in total QALYs of 3.05 and total costs of 116,941 CNY per patient. Treatment with Solitaire resulted in total QALYs of 2.81 and total costs of 99,090 CNY per patient. Trevo was dominated by EmboTrap as it was a more costly and less effective intervention. As such, Trevo was not cost-effective at any WTP threshold. Compared with Solitaire, EmboTrap was more effective and more costly, with an ICER of 23,615 CNY per QALY. This result suggests that EmboTrap is cost-effective when compared with Solitaire since the ICER was lower than all WTP thresholds assessed. Conclusion: EmboTrap dominated Trevo and is cost-effective for the treatment of patients with AIS compared with Solitaire when assessed from the perspective of the Chinese healthcare system and based on the device-level meta-analysis MASTRO I. Selecting a stent retriever (SR) that optimizes 90-day mRS score is an important consideration from both a clinical and healthcare payer perspective in China as it is associated with reduced long-term costs and increased quality of life.

Transcatheter vacuum-assisted aspiration of large intracardiac and intravascular masses.

Intravascular and intracardiac masses are usually represented by thrombi, tumours, and vegetations. They can affect both the right and left chambers of the heart and the venous and arterial circulation. Traditionally, their treatment is surgical or, in some circumstances, based on systemic anticoagulation/fibrinolysis. However, the complexity and frailty of patients who sometimes present with these conditions have pushed surgeons to find alternative minimally invasive effective treatments. While small masses can be removed with multiple devices, large masses are a more challenging problem. Vacuum-assisted aspiration systems such as the AngioVac System were developed to treat intravenous and right-sided heart thrombi. The application of the AngioVac System was widened to right-sided endocarditis and, later, to left-sided thrombi and vegetations. This review summarises the clinical results of different uses of the vacuum-assisted aspiration system to treat intravenous and intracardiac masses.

Clinical comparison of aspiration to stentriever-mediated aspiration thrombectomy for M2 occlusions.

OBJECTIVE: While revascularization for M2 occlusions is generally recommended and considered beneficial, the optimal approach (aspiration vs stentriever/combined) is less well defined in the literature. We sought to compare outcomes after thrombectomy with manual aspiration thrombectomy alone (MAT) or stentriever-mediated aspiration thrombectomy (SMAT) MATERIALS AND METHODS: To circumvent inter-operator technical variability, patients underwent thrombectomy for M2 occlusions by a single operator and were stratified by first pass approach: manual aspiration thrombectomy (MAT/aspiration alone) and stentriever-mediated manual aspiration thrombectomy (SMAT/combination). Efficacy outcomes included good reperfusion (mTICI score ≥2b) and a favorable 90-day functional outcome (mRS score of ≤2). Safety outcomes included 90-day mortality and symptomatic intracranial hemorrhage. RESULTS: One hundred three patients were identified: 57 underwent MAT whereas 46 underwent SMAT. Good reperfusion (TICI 2b or greater) was comparable between groups (93.5 % vs. 87.7 %, P=0.33). The intracranial hemorrhage rate was higher with SMAT compared to MAT (13 % vs. 1.8 %, P=0.04). Puncture-to-recanalization time was longer in SMAT (34.4 vs. 19.9 minutes, P<0.001). In multivariable analysis, complete or good reperfusion was associated with shorter puncture-recanalization time (adjusted odds ratio [aOR], 0.85) or less total passes (aOR, 0.58), respectively. In a propensity score matched analysis of 66 patients with comparable baseline and technical efficiency, the safety outcomes were not different between SMAT and MAT groups. CONCLUSIONS: SMAT compared with MAT did not result in an improved revascularization rate or functional outcome, while it was related to more hemorrhagic complications and mortality. Given cost and time savings with manual aspiration alone, this approach may be optimal as first line for M2 occlusions.

Endovascular clot removal in small and tortuous arteries: a case series.

Acute limb ischemia (ALI) due to arterial thromboembolic occlusion is a critical emergency in vascular medicine, requiring attention for rapid diagnosis and intervention, to prevent limb loss and major amputation, which is associated with patient disability in the long term. Traditionally, surgical embolectomy has been used for the treatment of ALI. Endovascular treatment of ALI traditionally involved catheter-directed thrombolysis. This option, however, poses some limitations, including an increased risk for access site and systemic bleeding complications, especially in patients with high bleeding risk. Therefore, in the last decades, several devices have been developed and tested for the mechanical endovascular treatment of ALI. Such devices involve either rotational thrombectomy or continuous thrombus aspiration. While rotational thrombectomy is limited in rather large arteries due to the risk of dissection and perforation in arteries <3 mm, continuous thrombus aspiration can be applied in smaller vessels and tortuous anatomies. In our case series we present a minimal-invasive endovascular approach for the treatment of two patients with ALI due to thrombotic occlusion of tortious and small diameter arteries. Minimal-invasive mechanical thrombectomy using the Penumbra Aspiration System emerged as a successful alternative to surgical embolectomy, enabling prompt treatment and with a short hospital stay for both patients. Our article therefore highlights the use of continuous thrombus aspiration in small diameter vessels and tortuous anatomies, which may represent a contraindication for the use of rotational thrombectomy. In addition, this technique may be applied even in patients with higher bleeding risk since additional lysis is not necessary in patients, where complete thrombus removal can be achieved by this device.

Comparison of clinical, technical, and safety outcomes between the Sofia 5Fr catheter vs. the Sofia 6Fr catheter; a MaSQ-Registry study.

BACKGROUND: Direct aspiration during endovascular treatment (EVT) for acute ischemic stroke (AIS) patients is safe and effective. The 'Soft torqueable catheter Optimized For Intracranial Access' (Sofia) catheter is commonly used. Data on differences between 5Fr and 6Fr Sofia is limited. Hence, we aimed to compare the clinical, technical, and safety outcomes between both Sofia catheters in AIS patients. METHODS: Patients with an intracranial anterior circulation occlusion from the 'Maastricht Stroke Quality-registry' (MaSQ-registry), who underwent EVT for AIS from September 2020 to February 2023, and treated with the Sofia catheter in the first-line technique were included. Outcomes included a shift on the modified Rankin Scale (mRS) score at 90 days, favorable functional outcome (mRS 0-2), first-attempt recanalization rate, and per procedural complications. Multivariable regression analyses were performed with adjustments. RESULTS: Out of 511 registered patients in the MaSQ-registry, 366 patients were included. 281 patients (77 %) were treated with the Sofia 6Fr. No shift towards better outcomes on the ordinal mRS score at 90 days was observed in the Sofia 6Fr group compared to the 5Fr (adjusted common[ac] OR:1.34, 95 %CI:0.70-2.56). Favorable functional outcome (aOR:1.24, 95 %CI:0.49-3.13), and per procedural complications (aOR:1.04, 95 %CI:0.41-2.64) did not differ significantly between Sofia 6Fr and 5Fr. The Sofia 6Fr achieved higher first-attempt successful recanalization rates (53 % versus 34 %; aOR:2.28, 95 %CI:1.11-4.69), and lower total thrombectomy attempts (median:1 versus 2; aß:-0.63, 95 %CI:-1.21 to -0.05). CONCLUSIONS: The use of 6Fr Sofia aspiration catheter leads in this single-center registry to higher first-attempt successful recanalization rates and fewer thrombectomy attempts compared to the 5Fr Sofia catheter. However, this did not reflect in better clinical outcomes.

Anesthetic Management for Aspiration Thrombectomy Using the Penumbra Indigo System in Pediatric Patients with Congenital Heart Disease.

OBJECTIVE: To describe clinical characteristics and outcomes, including transfusion requirements, in pediatric patients with congenital heart disease undergoing aspiration thrombectomy. DESIGN: Retrospective chart review. SETTING: Quaternary academic children's hospital. PARTICIPANTS: Patients aged <18 years with congenital heart disease undergoing aspiration thrombectomy between November 2017 and February 2022. MEASUREMENTS AND MAIN RESULTS: Thirteen patients underwent mechanical thrombectomy with the Penumbra Indigo System. Their median age was 3.8 years, and median weight was 15.2 kg. Seven patients had palliated single ventricle circulation, and 6 had biventricular circulation. Nine patients had intensive care unit (ICU) admission before the procedure, and 12 required ICU admission after the procedure. Indications for thrombectomy included systemic venous thrombus in 7 patients, pulmonary arterial thrombus in 3 patients, systemic arterial thrombus in 2 patients, and systemic-to-pulmonary shunt occlusion in 1 patient. The median estimated blood loss was 7.7 mL/kg (interquartile range [IQR], 1.4-15.8 mL/kg; range, 0.5-51.5 mL/kg). Seven patients required intraoperative transfusion of packed red blood cells (n = 4), fresh frozen plasma (n = 2), platelets (n = 3), and/or cryoprecipitate (n = 1). In the patients requiring transfusion, the median transfusion volume was 22 mL/kg (IQR, 14.1-59.7 mL/kg, 9.3-132.8 mL/kg). Thrombectomy was successful in 8 of 13 patients, although 3 of these 8 patients experienced recurrent thrombosis. CONCLUSIONS: Mechanical aspiration thrombectomy is being increasingly used to treat critically ill pediatric patients and presents unique anesthetic considerations, particularly related to the need for volume and blood product resuscitation.

Feasibility, efficacy, and safety of mechanical thrombectomy via sheathless transradial access as a first-line strategy: A case series.

OBJECTIVE: Although mechanical thrombectomy (MT) is primarily performed via transfemoral access (TFA), transradial access (TRA) is a potential alternative in older patients or those with tortuous vessels. However, the small radial artery diameter restricts the use of large-bore balloon guides and aspiration catheters, a limitation that may be overcome using the sheathless technique. Thus, we aimed to explore the feasibility, efficacy, and safety of sheathless TRA-MT as a first-line treatment approach for acute ischemic stroke. METHODS: This single-center retrospective case series included patients who underwent TRA-MT as first-line treatment between September 2020 and June 2023. Per our MT protocol, TRA was not the first-line approach in cases of left anterior circulation lesions with a type 3 aortic arch. We evaluated treatment effectiveness based on the successful recanalization rate, puncture-to-recanalization time, and modified first-pass effect; access route effectiveness based on the puncture-to-first-pass time and switch-to-TFA rate; and procedure safety based on procedure-related and severe puncture site complications. RESULTS: Sheathless 8-F guide catheters were used in 68 % and large-bore aspiration catheters in 70 % of the procedures. Successful recanalization was achieved in 98 % of the patients, with a modified first-pass effect in 54 % of them. The median puncture-to-first-pass and puncture-to-recanalization times were 20.5 and 33 min, respectively. The rate of procedure-related complications was low (4 %), with no severe puncture site complications. CONCLUSION: Sheathless TRA-MT enabled the use of large-bore guide and aspiration catheters, providing a swift approach to the target and satisfactory outcomes, and might be an effective first-line treatment for acute ischemic stroke.

Single-center experience with the JETi Hydrodynamic Thrombectomy System for acute limb ischemia.

OBJECTIVE: Acute limb ischemia (ALI) remains a vascular emergency with high morbidity and mortality. While the JETi Hydrodynamic Thrombectomy System (Abbott) offers a percutaneous approach to fragment and aspirate the thrombus in patients with arterial occlusions, data on its efficacy and safety are limited. This study reports our early experience using the JETi device to treat ALI at our institution. METHODS: This is a single-center, retrospective review of patients with ALI treated with the JETi device between September 2020 and December 2022. Patients were included if the JETi device was used either as a primary intervention or as an adjunct procedure. The primary endpoint was technical success defined as <50% residual thrombus after intervention. Secondary endpoints included achieving complete resolution of the thrombus on angiogram, acute kidney injury (AKI), major bleeding, 30-day major amputation, and 30-day mortality. RESULTS: A total of 59 JETi procedures for ALI (median age 62 years [interquartile range: 56-71 years]) were performed on 39 male and 20 female patients. The median time from onset of symptoms to hospitalization was 24 hours (interquartile range: 4-168 hours). Rutherford classifications were I (10), IIa (27), IIb (14), and undocumented (8). Etiology of ALI was native vessel thrombosis (27), embolism (16), graft/stent thrombosis (14), and iatrogenic (2). A total of 124 vessels were treated, with an average of 2.1 vessels per procedure. The primary outcome was achieved in 86% (107/124) of the arteries, with 82% (102/124) successfully opened using the JETi device alone without the need for any adjunctive therapy. Complete resolution of the thrombus using JETi was achieved in 81% (101/124) arteries, with or without the use of adjunctive therapy. A total of 6.7% (4/59) patients required a major limb amputation within 30 days despite successful recanalization, and one 30-day mortality was recorded. Complications included distal embolization (5), access site hematoma (2), and AKI (4). No major bleeding, hemolysis-induced AKI, or vessel dissection or perforation was observed. CONCLUSIONS: The JETi device appears to be a safe and effective percutaneous treatment option in the management of ALI. It provides definitive treatment with a high technical success rate of 86% and a good safety profile.

Serial dilation to enable ulnar artery access for endovascular neurointervention: Technical report and systematic review of the literature.

BACKGROUND: For rare neuro-endovascular cases in which transfemoral access is not feasible and the palmar circulation is insufficient for radial artery access, ulnar artery access may be considered. MATERIALS AND METHODS: Mechanical thrombectomy via ulnar artery access was performed to preserve the dominant radial artery. The ulnar artery was serial dilated to 7-French with microdilator. Angiography was performed using a diagnostic catheter. The sheath was exchanged for a guide catheter, and a triaxial system was inserted. A mechanical thrombectomy was performed. The systematic literature review included all studies pertaining to techniques for ulnar artery access for neurointervention in the last 20 years (2003-2023) published in the PubMed, Web of Science, and Embase databases. RESULTS: 67-year-old male developed left MCA syndrome in the setting of an infected abdominal aortic endograft. A transfemoral approach was ruled out due to concern for crossing the infected endograft. Allen test and ultrasound demonstrated that the right radial artery was of adequate size for access, but the ulnar artery was insufficient to support the palmar arch. Mechanical thrombectomy resulted in TICI 3 reperfusion. Systematic review of the literature yielded 2 case series and 1 case report of transulnar neurovascular procedures. Access site complications were rare and included 3 access site hematomas and 1 ulnar artery occlusion. CONCLUSION: We report our technique of serial dilation of the ulnar artery for neuroendovascular procedures and provide a systematic review of the literature for complication avoidance in ulnar artery access.

Single-Center Experience With Endovascular Therapy in Acute Occlusion of ICAS: Preferred Stent Thrombectomy Versus Preferred Angioplasty.

OBJECTIVES: The preferred endovascular therapy (EVT) for large-vessel occlusion in intracranial atherosclerosis (ICAS) is unknown. We compared the efficacy of preferred stent thrombectomy and preferred angioplasty in patients with acute large-vessel occlusion in ICAS. METHODS: Data from consecutive EVT patients (May 2020 to September 2023) with acute middle cerebral artery occlusion in ICAS were retrospectively analyzed. Preferred angioplasty was performed if there was a preoperative "microcatheter first-pass effect;" otherwise, preferred stent thrombectomy was performed. Analyses were grouped according to the two EVT treatments. Clinical data of all patients, including the time from puncture to recanalization, rate of successful reperfusion, early neurological improvement, intracranial hemorrhage, and modified Rankin Scale score at 90 days, were recorded and analyzed. RESULTS: Six-two patients were enrolled in this study (mean age was 60.66±13.21 y, 22.6% female). The preferred angioplasty group had a higher first-pass recanalization rate than the preferred stent thrombectomy group (61.3% vs. 21.9%, P <0.001) and a higher proportion of patients who were functionally independent (defined as a modified Rankin Scale score of 0 to 3) at 90 days [odds ratio,3.681; 95% confidence interval (CI):1.009 to 13.428; P =0.048]. There was no significant difference between the groups in the time from puncture to recanalization, the frequency of successful reperfusion, and early neurological improvement, or intracranial hemorrhage ( P >0.05). CONCLUSIONS: This study suggests that for acute middle cerebral artery occlusion in ICAS, preferred angioplasty may be a safe and effective procedure.

Percutaneous pulmonary aspiration thrombectomy in an adolescent fontan patient using a large-bore system.

We describe the safe and effective percutaneous pulmonary thrombectomy in an 18-year-old female with a Fontan circulation using the FlowTriever® device (Inari Medical®, Irvine, US). Aspiration thrombectomy of both pulmonary arteries was performed using 24 and 16 F FlowTriever® catheters retrieving large amounts of thrombus material resulting in near total angiographic recanalization.

Combining Novel Thrombectomy Devices for Intracardiac Mass Extraction: The Kong and Godzilla of Mass Extraction.

Transcatheter extraction of an intracardiac mass is a newer approach that may lead to nonsurgical treatment of complex cardiac masses. We present a case in which thrombectomy devices were combined to extract a right atrial mass, which highlights new frontiers in the treatment of complex transcatheter mass extraction. The combined use of two transcatheter thrombectomy devices (Kong and Godzilla) may provide a powerful addition to the existing armamentarium.

Safety and efficacy of stent retrievers plus contact aspiration in patients with acute ischaemic anterior circulation stroke and positive susceptibility vessel sign in France (VECTOR): a randomised, single-blind trial.

BACKGROUND: Positive susceptibility vessel sign (SVS) in patients with acute ischaemic stroke has been associated with friable red blood cell-rich clots and more effective recanalisation using stent retrievers versus contact aspiration. We compared the safety and efficacy of stent retrievers plus contact aspiration (combined technique) versus contact aspiration alone as the first-line thrombectomy technique in patients with acute ischaemic anterior circulation stroke and SVS-positive occlusions. METHODS: Adaptive Endovascular Strategy to the Clot MRI in Large Intracranial Vessel Occlusion (VECTOR) was a prospective, randomised, open-label study with blinded evaluation. Patients with SVS-positive anterior circulation occlusions on pretreatment MRI and arterial puncture within 24 h of symptom onset were enrolled from 22 centres in France. A centralised web-based method was used by interventional neuroradiologists for dynamic randomisation by minimisation. Patients were randomly assigned 1:1 to the combined technique or contact aspiration alone. The primary outcome was expanded Thrombolysis in Cerebral Infarction (eTICI) grade 2c or 3 reperfusion after three or fewer passes on post-treatment angiogram, adjudicated by a blinded independent central imaging core laboratory. The intention-to-treat population was used to assess the primary and secondary outcomes. This trial is registered with ClinicalTrials.gov (NCT04139486) and is complete. FINDINGS: Between Nov 26, 2019, and Feb 14, 2022, 526 patients were enrolled, of whom 521 constituted the intention-to-treat population (combined technique, n=263; contact aspiration alone, n=258). The median age of participants was 74·9 years (IQR 64·4-83·3); 284 (55%) were female and 237 (45%) male. The primary outcome did not differ significantly between groups (152 [58%] of 263 patients for the combined technique vs 135 [52%] of 258 for contact aspiration; odds ratio [OR] 1·27; 95% CI 0·88-1·83; p=0·19). Procedure-related adverse events occurred in 32 (12%) of 263 patients in the combined technique group and 27 (11%) of 257 in the contact aspiration group (OR 1·14; 0·65-2·00; p=0·65). The most common adverse event was intracerebral haemorrhage (146 [56%] of 259 patients for the combined technique vs 123 [49%] of 251 for contact aspiration; OR 1·32; 0·91-1·90; p=0·13). All-cause mortality at 3 months occurred in 57 (23%) of 251 patients in the combined technique group and 48 (19%) of 247 in the contact aspiration group (OR 1·19; 0·76-1·86; p=0·45), none of which was treatment-related. INTERPRETATION: The results of the VECTOR trial do not show superiority of the combined stent retriever plus contact aspiration technique over contact aspiration alone in patients with SVS-positive occlusion with respect to achieving eTICI 2c-3 within three passes. These findings support the use of either the combined technique or contact aspiration alone as the initial thrombectomy strategy in patients with acute anterior circulation stroke with SVS on pretreatment MRI. FUNDING: Cerenovus.

The Safety and Efficacy of ZelanteDVT™ Catheter Rheolytic Thrombectomy in the Treatment of Patients with Iliac Vein Stent Thrombosis.

BACKGROUND: To examine the safety and efficacy of ZelanteDVT™ catheter rheolytic thrombectomy in the treatment of patients with iliac vein stent thrombosis. METHODS: A retrospective analysis method was conducted by means of collecting the data of 32 patients who had completed the treatment of iliac vein stent thrombosis with ZelanteDVT catheter rheolytic thrombectomy from March 2019 to March 2023. Data on clinical characteristics, technical success, clinical success, complications, and early follow-up were analyzed. RESULTS: The technical success rates were 100%, intraoperatively, in which 22 cases were improved to thrombus clearance Grade II (50-90%), 10 were Grade III (>90%). There were 21 cases treated with subsequent catheter-directed thrombolysis, and the average urokinase administration of (120.90 ± 29.63)∗10ˆ4 units. The clinical success rates were 100% and the swelling of the affected limbs were significantly improved, a significant difference in the pre/postoperative between-thigh circumference difference [(5.16 ± 1.08) vs. (1.75 ± 0.84), P < 0.000]. The pre/postoperative Venous Clinical Severity Score was [(12.94 ± 1.70) vs. (7.44 ± 1.31), P < 0.000]. No serious complications occurred during the perioperative period. The postoperative and 12-month stent patency rate was 100.00% (32/32) and 71.88% (23/32), respectively. CONCLUSIONS: The ZelanteDVT catheter rheolytic thrombectomy seems to have a promising application prospect for the treatment of patients with iliac vein stent thrombosis.

Hepatic Artery Thrombectomy after Orthotopic Liver Transplantation: A Stent Retriever and/or Aspiration-Guided Catheter Approach.

Retransplantation has been the primary treatment for hepatic artery thrombosis (HAT) in patients with orthotopic liver transplant (OLT); however, because of scarcity of grafts, endovascular revascularization via mechanical thrombectomy offers an alternative to retransplantation should it provide similar long-term benefits. Data regarding a series of 8 patients with hepatic artery thrombectomies across 10 procedures (1 early HAT and 9 late HAT) utilizing stent retriever and/or suction catheter were collected. All had technically successful restoration of flow with stent placement of the anastomotic stenosis in 8 cases. Two patients required reintervention for HAT at 18 and 701 days after primary intervention, with the first dying from liver failure but with a patent hepatic artery on explant. One case had a procedure-related adverse event, hepatic artery dissection, Society of Interventional Radiology (SIR) adverse event classification of 2. Technical success was achieved in all procedures, demonstrating promise in effectively treating HAT in patients with OLT.

Autonomous navigation of catheters and guidewires in mechanical thrombectomy using inverse reinforcement learning.

PURPOSE: Autonomous navigation of catheters and guidewires can enhance endovascular surgery safety and efficacy, reducing procedure times and operator radiation exposure. Integrating tele-operated robotics could widen access to time-sensitive emergency procedures like mechanical thrombectomy (MT). Reinforcement learning (RL) shows potential in endovascular navigation, yet its application encounters challenges without a reward signal. This study explores the viability of autonomous guidewire navigation in MT vasculature using inverse reinforcement learning (IRL) to leverage expert demonstrations. METHODS: Employing the Simulation Open Framework Architecture (SOFA), this study established a simulation-based training and evaluation environment for MT navigation. We used IRL to infer reward functions from expert behaviour when navigating a guidewire and catheter. We utilized the soft actor-critic algorithm to train models with various reward functions and compared their performance in silico. RESULTS: We demonstrated feasibility of navigation using IRL. When evaluating single- versus dual-device (i.e. guidewire versus catheter and guidewire) tracking, both methods achieved high success rates of 95% and 96%, respectively. Dual tracking, however, utilized both devices mimicking an expert. A success rate of 100% and procedure time of 22.6 s were obtained when training with a reward function obtained through 'reward shaping'. This outperformed a dense reward function (96%, 24.9 s) and an IRL-derived reward function (48%, 59.2 s). CONCLUSIONS: We have contributed to the advancement of autonomous endovascular intervention navigation, particularly MT, by effectively employing IRL based on demonstrator expertise. The results underscore the potential of using reward shaping to efficiently train models, offering a promising avenue for enhancing the accessibility and precision of MT procedures. We envisage that future research can extend our methodology to diverse anatomical structures to enhance generalizability.

Current Approaches and Methods to Understand Acute Ischemic Stroke Treatment Using Aspiration Thrombectomy.

Acute ischemic stroke occurs when a blood clot occludes a cerebral artery. Mechanical interventions, primarily stent retrievers and aspiration thrombectomy, are used currently for removing the occluding clot and restoring blood flow. Aspiration involves using a long catheter to traverse the cerebral vasculature to reach the blood clot, followed by application of suction through the catheter bore. Aspiration is also used in conjunction with other techniques such as stent retrievers and balloon guide catheters. Despite the wide use of aspiration, our physical understanding of the process and the causes of the failure of aspiration to retrieve cerebral clots in certain scenarios is not well understood. Experimental and computational studies can help develop the capability to provide deeper insights into the procedure and enable development of new devices and more effective treatment methods. We recapitulate the aspiration-based thrombectomy techniques in clinical practice and provide a perspective of existing engineering methods for aspiration. We articulate the current knowledge gap in the understanding of aspiration and highlight possible directions for future engineering studies to bridge this gap, help clinical translation of engineering studies, and develop new patient-specific stroke therapy.

Antegrade and Retrograde Approaches with a Mechanical Thrombectomy Device for the Treatment of Acute Lower Limb Deep Vein Thrombosis.

OBJECTIVE: To examine the efficacy of antegrade and retrograde approaches with the AngioJet thrombectomy device for the treatment of acute lower limb deep vein thrombosis (DVT) and to evaluate the necessity of filter placement. METHODS: The clinical data of patients with acute lower limb DVT treated with the AngioJet device from January 2021 to June 2023 were retrospectively analyzed. The patients were divided into the antegrade and retrograde treatment groups according to the surgical approach and the direction of valve opening. The thrombosis interception rate of the filter, incidence of pulmonary embolism (PE), thrombectomy effectiveness, venous obstruction rate, and thrombosis recurrence rate of each treatment group were evaluated. In addition, factors affecting patency were analyzed. RESULTS: AngioJet was employed for 84 patients with acute lower limb DVT, treating a total of 88 limbs. The thrombosis interception rate of the filter was 35.7% (30 patients). The incidence of new PE or PE exacerbation was 6.0% (5 patients), and a filter retrieval rate of 97.6% (82 patients) was detected. Thrombus removal of grade III occurred in 35 (64.8%) of the 54 limbs (61.4%) in the antegrade treatment group versus 13 (38.2%) of the 34 limbs (38.6%) in the retrograde treatment group (P < 0.05). At 3 months, venous patency and bleeding events involved 52 (96.3%) and 4 (7.4%) limbs in the antegrade treatment group, respectively, versus 29 (85.3%) and 2 (5.9%) in the retrograde treatment group, respectively (P > 0.05). Regression analysis was performed to determine factors that may affect 3-month patency in both groups. Statistically significant linear relationships were found between 3-month patency and thrombus removal rate [odds ratio [OR] = 0.546 (0.326, 0.916)], thrombus formation time [OR = 1.018 (1.002, 1.036)], and preoperative thrombosis score [OR = 1.012 (1.002, 1.022)] in the antegrade treatment group, as well as thrombus removal rate [0.473 (0.229, 0.977)] in the retrograde treatment group. In regression analysis of factors affecting patency in both groups and the venous clinical severity score/Villalta score, a statistically significant linear relationship was found between thrombus formation time and the venous clinical severity score in the antegrade treatment group [0.576 (0.467, 0.710)]. CONCLUSIONS: Both antegrade and retrograde approaches are safe and effective for the treatment of acute lower limb DVT. There are no differences in 3-month deep vein patency and post-thrombotic syndrome (PTS) incidence rates. Individuals with acute lower limb DVT are at high risk of thrombus shedding after treatment with AngioJet thrombectomy, and placement of a vena cava filter (VCF) is recommended for effective interception.