Aspiration Catheter Research Articles

Demographics and prognosis of patients with pyogenic liver abscess due to Klebsiella pneumonia or other species

BackgroundPyogenic liver abscess (PLA) is a potentially life-threatening intra-abdominal infection. We compared the clinical features, treatments, and prognoses of patients who had Klebsiella pneumonia pyogenic liver abscess (KPPLA) and non-Klebsiella pneumonia pyogenic liver abscess (non-KPPLA). MethodsA retrospective analysis was used to compare the medical records of KPPLA and non-KPPLA patients with positive pus cultures at a single hospital in China from January 2017 to December 2019. ResultsWe examined 279 patients with definitively established PLA, 207 (74.2 %) with KPPLA, and 72 with non-KPPLA. The non-KPPLA group had a higher Charlson comorbidity index, longer hospital stay, longer duration of fever, and greater hospital costs. Multivariate analysis showed that alcohol intake (OR: 2.44, P = 0.048), cancer (OR: 4.80, P = 0.001), ICU admission (OR: 10.61, P = 0.026), resolution of fever OR: 1.04, P = 0.020), and a positive blood culture (OR: 2.87, P = 0.029) were independent predictors of primary treatment failure. Percutaneous needle aspiration (PNA) and pigtail catheter drainage (PCD) provided satisfactory outcomes, but PNA led to shorter hospital stays and reduced costs, especially in KPPLA patients whose abscesses were smaller than 10 cm. ConclusionKPPLA and non-KPPLA patients had some differences in comorbidities and treatment strategies, and non-KPPLA patients had a significantly worse prognosis.

Safety and Clinical Outcomes of Two-Session Catheter-Directed Sclerotherapy Using Ethanol for Endometrioma.

To evaluate the safety and clinical outcome of two-session catheter-directed sclerotherapy (CDS) with 99% ethanol in patients with endometrioma. This prospective study was approved by the institutional review board with written informed consent obtained from all participants and was registered on clinicaltrial.gov. Consecutive patients with ovarian endometrioma between June 2020 and March 2023 were prospectively evaluated for two sessions of CDS. After successful transvaginal ultrasound-guided puncture of the endometrioma, the biopsy needle was exchanged for a 7- or 8.5-F catheter for aspiration and ethanol injection. The catheter was retained in situ for a second session the next day. Endometrioma volume was measured on ultrasound before and 1, 3, and 6 months after CDS, and volume reduction ratio (VRR) was calculated. Serum anti-Müllerian hormone (AMH) was measured before and 6 months after CDS to assess ovarian reserve. Thirty-one endometriomas in 22 patients (mean age, 31.0 years; range, 19-44 years) were treated; 28 endometriomas were successfully treated with two-session CDS, while one session was incomplete in three endometriomas in three patients due to contrast medium leakage or pain. Minor procedure-related complications developed in four patients and resolved spontaneously before discharge on the same day of the second session. No recurrence was identified during follow-up. At the 6-month follow-up, the mean endometrioma diameter decreased from 5.5 ± 1.7 to 1.4 ± 0.9 cm (P < 0.001), and the serum AMH level was lowered without statistical significance (1.37 ± 0.96 ng/mL vs. 1.18 ± 0.92 ng/mL; P = 0.170). VRRs at 1, 3, and 6 months after CDS were 84.3 ± 13.7%, 94.3 ± 5.8%, and 96.4 ± 4.7%, respectively. Two-session CDS with 99% ethanol is safe, feasible, and effective for treating endometrioma with the ovarian function well preserved.

Assessment of the safety and efficacy of the Zoom 45 and 55 reperfusion catheters for medium and distal mechanical thrombectomies: A multi-institutional study

IntroductionThe Zoom aspiration catheters harbor novel dimensions and construction to enhance trackability and deliverability. In addition, a beveled tip may improve thrombus interaction and aspiration force for a set inner diameter. This study evaluates their utility in medium and distal vessel occlusions. ObjectiveTo evaluate the safety and efficacy of Zoom 45 and 55 aspiration catheters in medium and distal vessel thrombectomy. MethodsPatients treated for distal vessel occlusions via mechanical thrombectomy utilizing either the Zoom 45/55 catheter or a historical control catheter between 2021–2022 at two institutions were included in this study. Medium and distal occlusions were defined as any anterior or posterior cerebral artery branch as well as the M2-4 segment of the middle cerebral artery (MCA). Preprocedural, procedural, and postprocedural variables were obtained. ResultsThirty-eight patients underwent thrombectomy with Zoom 45 or 55 catheters; four had multiple occluded vessels. Occlusion location included the M2 in 32 cases, M3-4 in 7 cases, A2 in 2 cases and P2 in 1 case. The mean number of passes per occlusion was 1.6 and overall successful reperfusion (TICI 2b or greater) was achieved in 84 % of cases. There were no symptomatic procedure-related complications such as perforation or post-procedural symptomatic ICH. Modified Rankin scores rates of 0–2, 3–5, and 6 at three months post-procedure were 35.7 %, 21.4 %, and 42.9 %, respectively. ConclusionsThe Zoom beveled tip aspiration catheters are safe and effective for more challenging medium and distal vessel occlusions.

Safety and effectiveness of the Phoenix atherectomy device for endovascular treatment of common femoral and popliteal arteries: Results of the EN-MOBILE trial.

Background: This study aimed to assess the peri- and postprocedural outcomes of atherectomy-assisted endovascular treatment of the common femoral (CFA) and popliteal arteries. Methods: Phoenix atherectomy was used for the treatment of 73 and 53 de novo CFA and popliteal artery lesions, respectively, in 122 consecutive patients. Safety endpoints encompassed perforation and peripheral embolization. Postprocedural endpoints included freedom from clinically driven target lesion revascularization (CD-TLR) and clinical success (an improvement of ⩾ 2 Rutherford category [RC]). In addition, 531 patients treated for popliteal artery stenosis or occlusion without atherectomy were used as a comparator group. Results: Procedural success (residual stenosis < 30% after treatment) was 99.2%. The need for bail-out stenting was 2 (2.7%) and 3 (5.7%) in CFA and popliteal artery lesions, respectively. Only one (1.4%) embolization occurred in the CFA, which was treated by catheter aspiration. No perforations occurred. After 1.50 (IQR = 1.17-2.20) years, CD-TLR occurred in seven (9.2%) and six (14.6%) patients with CFA and popliteal artery lesions, respectively, whereas clinical success was achieved in 62 (91.2%) and 31 (75.6%), respectively. Patients treated with atherectomy and DCB in the popliteal artery after matching for baseline RC, lesion calcification, length, and the presence of chronic total occlusion, exhibited higher freedom from CD-TLR compared to the nondebulking group (HR = 3.1; 95% CI = 1.1-8.5, p = 0.03). Conclusion: Atherectomy can be used safely and is associated with low rates of bail-out stenting in CFA and popliteal arteries. CD-TLR and clinical success rates are clinically acceptable. In addition, for the popliteal artery, atherectomy combined with DCB demonstrates lower CD-TLR rates compared to a DCB alone strategy. (German Clinical Trials Register: DRKS00016708).

Technical and clinical outcomes of thrombectomy in patients with acute medium vessel occlusion and large vessel occlusion; sub-analyses of Japan Trevo registry

BackgroundLittle is known about endovascular therapy (EVT) for patients with medium vessel occlusion (MeVO) and more work is needed to establish its efficacy and to understand hemorrhagic complications. MethodsWe analyzed the Japan Trevo Registry, which enrolled patients with acute stroke who underwent EVT using Trevo Retriever alone or in combination with an aspiration catheter. The primary outcome was effective reperfusion, and the secondary outcome was modified Rankin scale 0–2 at 90 days. Safety outcomes, including intracranial hemorrhage (ICH), were evaluated using a subgroup analyses focused on any ICH. ResultsAmong 1041 registered patients, 1025 patients were analyzed. 253 patients had MeVOs, and the majority (89.3%) had middle cerebral artery segment 2 (M2). The median National Institutes of Health Stroke Scale scores at admission were 15 and 19 for the MeVO and LVO groups (p < 0.0001). The primary outcome was 88.9% in MeVO vs. 91.8% in LVO group: adjusted odds ratio (aOR) [95% confidence interval (CI)] 0.60 [0.35–1.03], p = 0.07, and the secondary outcome was 43.2% vs. 42.2%, and the aOR [95%CI] was 0.70 [0.48–1.002], p = 0.051. However, the incidence of any ICH was more prominent in MeVO than in LVO group (35.7% vs. 28.8%, aOR [95%CI] 1.54 [1.10–2.15], p = 0.01). In subgroup analyses, the incidences of any ICH in MeVO group were generally higher than those in LVO group. ConclusionsThe effective reperfusion rate did not differ significantly between MeVO and LVO groups. Future development of devices and treatments for MeVO with fewer hemorrhagic complications is desirable.

Mechanical Thrombectomy in Stroke-Retrospective Comparison of Methods: Aspiration vs. Stent Retrievers vs. Combined Method-Is Aspiration the Best Starting Point?

Background: There are three main methods of mechanical thrombectomy (MT): using a stent retriever (SR) only (SO), aspiration catheter (AC) only (AO) and the combined method (CM) using both the SR and AC. This paper describes a real-life, single-center experience using SO, AO and CM during 276 consecutive MTs. Methods: The primary endpoint was the frequency of first-pass complete (FPE TICI3). The secondary endpoints were final mTICI 2b-3, procedure duration, clinical outcome and the total number of device passes. The third aim of this study was to test the association between the clinical outcomes in patients treated with each method and various factors. Results: There was a significant difference (p = 0.016) between the groups' FPE TICI3 rates with 46% mTICI 3 in the AO group, 41% in the CM group and 21% in the SO group. AO resulted in procedure time shortening to a mean duration of 43 min, and the scores were 56 min for CM and 63 min for SO (p < 0.0001). There were no significant differences in clinical outcomes or in-hospital mortality. The analysis showed a correlation between good clinical outcomes and the administration of IVT: OR 1.71 (1.03-2.84) p = 0.039. Patients ≥66 years old had higher odds of a bad outcome compared to younger patients in general (OR, 1.99 95% CI, 1.17-3.38; p = 0.011). FPE TICI3 was associated with good functional outcomes in the whole treated cohort (OR, 1.98; 95% CI, 1.21-3.25; p = 0.006). Conclusions: In our series, AO proved to be the best starting point in most cases. It demonstrates good technical efficacy regarding FPE, it is fast and clinical outcomes seem to be the least age- and FPE TICI3-dependent. It can be easily converted into the combined method, which had the second-best outcomes in our cohort.

Thrombectomy

Endovascular procedures have become the standard treatment for acute stroke caused by large vessel occlusion. Various strategies are available, including stent retrieval, aspiration catheter placement, and combined techniques. However, the first-pass effect can be maximized using the technique most familiar to each surgeon and institution. Therefore, it is necessary to understand the characteristics of each device and develop case-specific treatment strategies.

Optimizing suction force in mechanical thrombectomy: Priming the aspiration tubing with air versus saline.

We sought to investigate how priming the tube between air versus air mixed with saline ex vivo influenced suction force. We examined how priming the tube influenced peak suction force and time to achieve peak suction force between both modalities. Using a Dwyer Instruments (Dwyer Instruments Inc., Michigan City, IN, USA), INC Digitial Pressure Gauge, we were able to connect a .072 inch aspiration catheter to a rotating hemostatic valve and to aspiration tubing. We recorded suction force measured in negative inches of Mercury (inHg) over 10 iterations between having the aspiration tube primed with air alone versus air mixed with saline. A test was used to compare results between both modalities. Priming the tube with air alone compared to air mixed with saline was found to have an increased average max suction force (-28.60 versus -28.20 in HG, p<0.01). We also identified a logarithmic curve of suction force across time in which time to maximal suction force was more prompt with air compared with air mixed with saline (13.8 seconds versus 21.60 seconds, p<0.01). Priming the tube with air compared to air mixed with saline suggests that not only is increased maximal suction force achieved, but also the time required to achieve maximal suction force is less. This data suggests against priming the aspiration tubing with saline and suggests that the first pass aspiration primed with air may have the greatest suction force.

Involvement of peptidylarginine deiminase 4 in eosinophil extracellular trap formation and contribution to citrullinated histone signal in thrombi

BackgroundExtracellular traps formed by neutrophils (NETs) and eosinophils (EETs) have been described in coronary thrombi, contributing to thrombus stability. A key mechanism during NET formation is histone modification by the enzyme PAD4. Citrullinated histones, the product of PAD4 activity, are often attributed to neutrophils. Eosinophils also express high levels of PAD4. ObjectivesWe aimed to explore the contribution of PAD4 to EET formation. MethodsWe performed immunohistological analyses on thrombi, including a large, intact, and eosinophil-containing thrombus retrieved from the right coronary artery using an aspiration catheter and stroke thrombi from thrombectomy retrieval. We studied eosinophils for their capability to form PAD4-dependent EETs in response to strong ET-inducing agonists as well as activated platelets and bacteria. ResultsHistopathology and immunofluorescence microscopy identified a coronary thrombus rich in platelets and neutrophils, with distinct areas containing von Willebrand factor and citrullinated histone H3 (H3Cit). Eosinophils were also identified in leukocyte-rich areas. The majority of the H3Cit+ signal colocalized with myeloperoxidase, but some colocalized with eosinophil peroxidase, indicating EETs. Eosinophils isolated from healthy volunteers produced H3Cit+ EETs, indicating an involvement of PAD4 activity. The selective PAD4 inhibitor GSK484 blocked this process, supporting PAD4 dependence of H3Cit+ EET release. Citrullinated histones were also present in EETs produced in response to live Staphylococci. However, limited evidence for EETs was found in mouse models of venous thrombosis or infective endocarditis. ConclusionAs in NETosis, PAD4 can catalyze the formation of EETs. Inhibition of PAD4 decreases EET formation, supporting the future utility of PAD4 inhibitors as possible antithrombotic agents.

Standardized approach to direct first pass aspiration technique for endovascular thrombectomy: Description and initial experience with CANADAPT

Background Endovascular thrombectomy (EVT) is standard of care for acute ischemic stroke. Stent assisted EVT with aspiration (SOLUMBRA) technique has remained a mainstay approach. There is growing evidence that A Direct Aspiration First Pass Technique (ADAPT) is a safe, efficient and effective approach for EVT, offering several advantages. This study describes and reports initial institutional experience in the use of a standardized scientific based aspiration only technique: CANADAPT. Methods Single center prospective cohort study was performed on consecutive patients treated for large/medium vessel ischemic stroke with CANADAPT. Intravenous thrombolytics were administered according to routine practice, independent of the decision to proceed with EVT. A sequential stepwise aspiration only technique was then applied, CANADAPT, consisting of three maneuvers, A, B and C. The reperfusion success rate, number of passes, use of rescue technique, complication rate and procedural cost were determined. Results Twenty-two patients were included in this case series representing M1 (17, 77%), M1/2 (2, 9%), carotid-T (2, 9%) and basilar (1, 5%) occlusions. First pass recanalization was achieved in 11 (50%) of patients. A further four patients had successful reperfusion with a second pass of CANADAPT (total 68% success rate). Only one patient had successful reperfusion with the aspiration catheter at the clot interface (CANADAPT A). All others required some withdrawal of the aspiration catheter for reperfusion (CANADAPT B and C). Seven patients had SOLUMBRA rescue. Of these, five patients (22% of total patients) had further successful reperfusion. Overall median procedural time was 23 min for first recanalization and 30 min for final recanalization. The cost per procedure was $6630 ± 1069 for CANADAPT, and $13,530 ± 2706 for SOLUMBRA techniques. Conclusions CANADAPT represents a standardized scientific-based approach to aspiration only thrombectomy intervention. This initial study demonstrates the safety, efficiency and efficacy of this technique for use in EVT.

Abstract TP201: Impact of Microguide Wire Stiffness on Microcatheter and Aspiration Catheter Navigation in Tortuous Vessels

Background and Purpose: Endovascular therapies require devices to access treatment sites safely and efficiently. Vessel tortuosity often complicates this navigation, increasing the risk of microguide wire (MGW) or microcatheter (MC) kickback, which may result in unstable device movements or sudden drop of devices. This study aims to elucidate the effect of MGW stiffness variability on the trackability of MC and aspiration catheters (AC). Methods: Using two silicone vascular models, we replicated the M2 segment of the middle cerebral artery (MCA) at an 80-degree branch (MCA model, Fig. A) and a severely tortuous internal carotid artery (ICA model, Fig. B). Experiments were conducted under conditions of 37°C, 60 BPM, and an ICA flow rate of 240 mL/min. In the MCA model, the MC (TrevoTrak21) was advanced from the M1 segment to distal M2 while three MGWs (Synchro SELECT Soft, Standard, Support) were placed at distal M2. In the ICA model, the AC (Zoom 71) was advanced from ICA to M1 with MC and MGW at distal M2. Maximum push force and kickback length were measured while TrevoTrack21 or Zoom71 were advanced at 4 mm/sec for 7 runs per device. One-way ANOVA assessed group differences. Results: In the MCA model, when using the Soft MGW, the MC recorded the highest pushing force at 59.3mN and kickback of 29.87mm. Conversely, the Support MGW demonstrated the least pushing force at 38.2mN (P&lt;0.001) and the shortest kickback length at 17.83mm (P&lt;0.001). For the ICA model, differences in forces across the MGW types were less distinct. However, the kickback length with the Soft MGW at 13.78mm was significantly greater than that with the Standard MGW at 6.26mm and the Support MGW at 6.76mm (P=0.026). Conclusion: Our findings suggest that MGWs with higher stiffness offer more stable guidance, requiring less force in both MC and AC navigation. Moreover, increased MGW stiffness consistently leads to shorter kickback lengths, emphasizing its importance in stable device navigation.

Abstract WP206: Single Center Experience Using the 3-Max Catheter in Medium and Distal Vessel Occlusion

Introduction: Stroke thrombectomy for medium and distal vessel occlusion is a topic of great interest with several clinical trials underway. We describe a single center experience with the Penumbra 3 max aspiration catheter in stroke thrombectomy. In our study, we compare the use of the 3 max as a de novo first pass catheter to its use as a rescue aspiration catheter following attempted thrombectomy with other devices. Methods: From January 2017 to January 2023, 84 patients underwent mechanical thrombectomy with use of a Penumbra 3 Max aspiration catheter at our comprehensive stroke center. Of these patients, 26 had 3 Max used as a first pass catheter (de novo) and 58 had it used on subsequent passes (rescue). We retrospectively reviewed these patient charts for demographic variables, and clinical and radiographic outcomes. We compared the effectiveness of the 3 Max catheter in achieving recanalization on first pass when used de novo, to the successful recanalization of a vessel when the 3 Max was used as a rescue device (“rescue rate”). Results: There were no significant differences in baseline demographic variables including age, gender, presenting NIHSS, and vascular risk factors between the de novo and rescue groups. There was no significant difference in location of occlusion and IV or IA thrombolytic use between the groups. The rescue rate was higher than the first pass effect [67.2% vs. 38.5%, X 2 (1, N =84) = 6.1, p&lt;.05]. Rates of successful thrombectomy, defined as TICI2c or better, were similar between the de novo and rescue groups (44.4% vs. 40.4%, p=0.722). The de novo group had higher rates of favorable outcome at 90 days (mRS 0-2), but this did not reach statistical significance (44% vs. 28.1%, p=0.158). Hemorrhage and mortality rates between the two groups were low and not statistically significant when compared to each other. Conclusion: Medium and distal vessel occlusion carry high rates of morbidity and deserve consideration of endovascular therapy. The Penumbra 3 Max catheter has a higher rescue recanalization rate than first pass recanalization rate. It appears to be a safe and effective device when used in mechanical thrombectomy.

A "Radial Ready" Tricoaxial Setup for Anterior Circulation Mechanical Thrombectomy: Technical Aspects and Preliminary Results.

Mechanical thrombectomy (MT) is the standard of care for acute ischemic stroke (AIS) due to large vessel occlusion (LVO). The choice of a transradial approach (TRA) for anterior circulation LVOs is still debatable; the use of a specific tricoaxial system could help mitigate numerous issues related to transradial MT. From November 2022 to November 2023, 22 patients underwent TRA-MT for anterior circulation LVOs, both as first-line and rescue from transfemoral approach (TFA) failure, with the same triaxial setup consisting of a 7F introducer sheath, 7F guide catheter, and aspiration catheters ranging from 5.5F to 5F in relation to the occlusion site. Choice of thrombectomy technique was at operator discretion. Patients' demographic data, clinical presentation, treatment details, complications, rate of crossover to TFA, successful revascularization (modified thrombolysis in cerebral infarction [mTICI] score ≥2b), and good clinical outcome at 3 months (modified Rankin scale [mRS] 0-2) were reported. Of 20 patients selected, 10 (50%) had occlusion of M1 segment of middle cerebral artery (MCA), 6 (30%) of internal carotid artery (ICA) terminus, and 4 (20%) with M2 MCA occlusions; 12/20 (60%) were right-sided occlusions and 8/20 (40%) were left-sided. The mean National Institutes of Health Stroke Scale score was 9.25 at admission. Successful revascularization to mTICI 2b-3 was achieved in 18/20 patients (90%). Intracranial complications were reported in 2 (10%) patients. Rate of radial artery occlusion at 24 hours was 10,6%; no access-site haemorrhagic complications were reported. Symptomatic intracranial hemorrhage occurred in 2 (10%) patients. mRS score 0-2 at 3 months was 50%. The high technical effectiveness and good safety profile of this specific tricoaxial setup for TRA-MT in AIS, even for large proximal LVOs, could constitute a viable alternative to TFA-MT in selected cases.

Exploring thrombus composition in cerebral venous thrombosis: the first case report with initial insights and implications for treatment advancements.

Endovascular thrombectomy (EVT) is a treatment option in patients with a cerebral venous thrombosis (CVT) who deteriorate despite anticoagulant treatment. Assessment of thrombus composition in CVT may provide insights into the pathophysiology of the disease and suggest new therapeutic strategies. A 47-year-old woman (smoking habit and estradiol/progesterone-releasing intra-uterine device) diagnosed with massive CVT underwent EVT (complete recanalization via aspiration catheter and stentriever) due to acute-onset left-sided weakness and dysarthria despite 72 h of full-dose subcutaneous low-molecular heparin. Two main reddish clots (maximum diameter 15 mm) were retrieved. Microscopic assessment showed an erythrocyte-rich thrombus (83.9% of entire thrombus surface) with layers of platelets/fibrin (lines of Zahn: 13.9% fibrin and 38.5% platelet [CD61+]). The immunological profile was dominated by neutrophils (30% MPO+), with neutrophil extracellular traps (NETs) in 1.9% of thrombus surface. T- (CD3+), B-lymphocytes (CD20+), and monocytes/macrophages (CD68+) were rather rare (2.2%, 0.7%, and 2.0% respectively). We found no evidence (0.0%) of hemosiderin and endothelial cells (CD34+). Full clinical recovery occurred prior to discharge. This is the first case report of a CVT with histologic assessment of the thrombus retrieved via EVT. Evaluating thrombi in CVT can provide key insights into disease pathophysiology and guide treatment advancements.

Inducing cavitation within hollow cylindrical radially polarized transducers for intravascular applications

Thrombotic occlusions of large blood vessels are increasingly treated with catheter based mechanical approaches, one of the most prominent being to employ aspiration to extract clots through a hollow catheter lumen. A central technical challenge for aspiration catheters is to achieve sufficient suction force to overcome the resistance of clot material entering into the distal tip. In this study, we examine the feasibility of inducing cavitation within hollow cylindrical transducers with a view to ultimately using them to degrade the mechanical integrity of thrombus within the tip of an aspiration catheter. Hollow cylindrical radially polarized PZT transducers with 3.3/2.5 mm outer/inner diameters were assessed. Finite element simulations and hydrophone experiments were used to investigate the pressure field distribution as a function of element length and resonant mode (thickness, length). Operating in thickness mode (∼5 MHz) was found to be associated with the highest internal pressures, estimated to exceed 23 MPa. Cavitation was demonstrated to be achievable within the transducer under degassed water (10 %) conditions using hydrophone detection and high-frequency ultrasound imaging (40 MHz). Cavitation clouds occupied a substantial portion of the transducer lumen, in a manner that was dependent on the pulsing scheme employed (10 and 100 μs pulse lengths; 1.1, 11, and 110 ms pulse intervals). Collectively the results support the feasibility of achieving cavitation within a transducer compatible with mounting in the tip of an aspiration format catheter.

Impact of atherosclerotic etiology on technical and clinical outcomes of mechanical thrombectomy with a stent retriever: subanalysis of the Japan Trevo Registry

BackgroundThe safety and effectiveness of stent retriever use for patients with acute large vessel occlusion (LVO) due to intracranial atherosclerotic disease (ICAD) is not well established. We investigated the differences...

Safety and Efficacy of Aspiration Catheter CAT6 and 5 Fr Navien in the Endovascular Treatment of Acute Ischemic Stroke.

Mechanical thrombectomy has become a key treatment option for acute ischemic stroke. This study compared the safety and efficacy of aspiration catheter CAT6 and 5 Fr Navien. Thrombectomy was performed in103 patients with the acute internal carotid artery, middle cerebral artery M1 or M2 occlusions, including the CAT6 group (n=53 with stent retriever and CAT6 aspiration) and the 5 Fr Navien group (n=50 with stent retriever and 5 Fr Navien aspiration) at the Advanced Stroke Center. Overall, an aspiration catheter placement success rate was achieved in 93.2% of cases, 52 (98.11%) for CAT6, and 44 (88.00%) for 5 Fr Navien ( P =0.042). Overall, 17 cases (16.51%) required additional guidewire rates, 5.66% for CAT6, and 13.592% for 5 Fr Navien ( P =0.002). First-pass success rate (FPSR) was achieved in 38.84% of cases overall, a rate that did not differ significantly between catheters: 45.28% for CAT6; 32.00% for 5 Fr Navien ( P =0.167). Final thrombolysis in cerebral infarction 2b or 3 reperfusion was achieved in 91.26% of cases overall, 51 (96.23%) for CAT6, and 43 (86%) for 5 Fr Navien ( P =0.066). The participants had a mean number of passes for the index thrombus of 1.956 and a median procedure time of 65.82±21.8 minutes. There was no significant difference found in 90-day good outcome (mean 42.7%, modified Rankin Score 0 to 2) and 90-day mortality (17%) between CAT6 and 5 Fr Navien. Aspiration catheter placement success rate and first-pass success rate seemed to be higher for CAT6 and, moreover, the rate of additional guidewires was lower.

"The microcatheter contrast injection technique": A novel technique to detect the proximal end of a thrombus in mechanical thrombectomy.

Background: An aspiration catheter needs to attach to a thrombus in order to achieve first-pass recanalization by mechanical thrombectomy (MT) for acute ischemic stroke (AIS), particularly that using a direct aspiration first pass technique. The meniscus sign, which is defined as meniscoid contrast opacification indicating the proximal edge of a thrombus, has been suggested to contribute to successful recanalization. In some cases, the meniscus sign is not detected following an injection of contrast medium through a guiding catheter. To precisely identify the location of a thrombus, we use "the microcatheter contrast injection (MCI) technique," which accurately shows the proximal edge of a thrombus. We herein introduce this novel technique and discuss its efficacy in MT. Methods: In cases without the meniscus sign, a microcatheter was advanced to the distal end of contrast opacification, and contrast medium was injected through the microcatheter to detect the meniscus sign. An aspiration catheter was then advanced to the thrombus indicated by the meniscus sign and slowly withdrawn under aspiration. Results: 29 patients underwent MT for AIS using the MCI technique. Even in cases without the meniscus sign on initial angiography, the MCI technique accurately revealed the proximal edge of the thrombus. Moreover, middle cerebral artery occlusion due to atherosclerotic stenosis and displacement of the aspiration catheter and thrombus axis were detected using this technique. Conclusions: The MCI technique may effectively reveal the exact site of a thrombus and increase the success rate of first-pass recanalization.

Advancing minimally invasive surgery: A cutting-edge cable-actuated conveying mechanism for reliable tissue transportation

Introduction Tissue extraction plays a crucial role in various medical disciplines, with aspiration catheters serving as the prevailing method. Unfortunately, these catheters face limitations such as clogging and dependence on tissue properties and device dimensions. Therefore, there is a pressing need for an improved tissue extraction device that enables efficient and reliable tissue removal during Minimally Invasive Surgery (MIS). Methods In this study, we present a novel tissue transport system that utilizes a cylindrical conveyor belt mechanism for reliable tissue transportation. We conducted experiments using a proof-of-principle prototype to explore the influence of tissue elasticity, rotational velocity, instrument orientation, and tissue shape on the transportation rate, efficiency, and reliability. Tissue phantoms with gelatine concentrations of 3, 9, and 12 wt% were employed to simulate a range of Young’s moduli from 1 to 110 kPa. Results The mean transportation rates for these phantoms were 7.75±0.48, 8.43±1.50, and 8.90±0.56 g/min, respectively. Notably, all phantoms were transported successfully. The perfect reliability exhibited underscores the potential of our instrument as an alternative to aspiration catheters. CONCLUSION: This research presents a significant step forward in the field of tissue extraction, offering a promising approach for MIS with enhanced efficiency and reliability.

Coronary balloon-assisted navigation of aspiration catheter for stroke thrombectomy.

In recent years, A Direct Aspiration First Pass Technique (ADAPT) has emerged as an effective and safe method of thrombectomy. Large trials have shown noninferiority of ADAPT compared to primary stent retriever approach, while new studies emphasize on its shorter procedural time with potentially fewer complications and costs.1,2. Failure of the A Direct Aspiration First Pass Technique (ADAPT) is often due to the inability to successfully navigate the aspiration catheter to the thrombus site. As a solution, several techniques have been considered such as the use of stiffer microcatheters or a wedge device.3 In Video 1, we present our technique of navigating aspiration catheters with the assistance of coronary balloons. This technique has been very successful in our experience of about 30 cases in the past 6 months. Thanks to its safety and efficacy, this technique has dramatically changed our technical management of acute ischemic stroke. It can increase the ADAPT success rate while potentially reducing procedural costs.