Zoom71 navigation: Does tip orientation matter?

BackgroundRecent introduction of large bore aspiration catheters have contributed to high reperfusion rates. The alteration of these catheters to have angled tips, which increase clot engagement area by approximately 15%,...

IntroductionIn addition to enlarging the catheter tip diameter, recent aspiration catheters were designed with a novel angled tip design. We aimed to evaluate the efficacy of new generation angled tip...

IntroductionWith the advent of smaller stent retrievers (SR) and aspiration catheters (AC) capable of accessing more distal locations, distal and medium vessel occlusions (DMVO) are emerging as promising targets for endovascular thrombectomy (EVT). However, considering the vulnerability of distal vessels to injury, it is imperative to understand the safety of various frontline techniques in these challenging scenarios. Using a vascular flow model, we sought to investigate the optimal size, strategy, and positioning of a stent retriever and aspiration catheter to minimize the pulling force exerted on the M2 vasculature.MethodsWe used a silicone vascular flow model with moderate tortuosity that replicated the left‐sided anterior circulation, including middle cerebral artery (MCA) branches in the M2 territory. An 8 French Cook Shuttle guide sheath was inserted coaxially with a Catalyst 7‐132 cm aspiration catheter and TrevoTrak 21 microcatheter. To measure pulling force, an Imada force gauge DST‐1A was placed at the M2 and a DST‐11A at the proximal end of the microcatheter. The Solitaire 4x20 mm Solitaire stent‐retriever was pulled at 4 mm/sec with the AC in the proximal cavernous carotid segment (NoAsp), proximal M1 (M1P), and distal M1 (M1D), a total of 8 times per AC position, using the ingestion technique. The pinching technique was also examined using the 4x20mm stent.ResultsThe average pulling force measured on M2 using the 4x20mm stent was 169.1mN with the AC docked in the proximal NoAsp position, 26.5mN with the AC at M1P, and 23.0mN at M1D (p<0.0001). The difference in pulling force between M1P and M1D was not significant (p=0.472). The average pulling force exerted on M2 from pinching the 4x20mm stent with the AC at M1D, rather than ingestion of the stent at M1D, was 62.9mN. Average pulling force was noted to decrease from the first to the last run in most cases, with an average drop of 26.4% at the fourth run.ConclusionADAPT and stent‐retrieval have recently been shown to be comparable in DMVO (1), however some studies have suggested a combined approach may reduce bleeding complications compared to stent‐retrieval alone (2). In our in‐vitro model, we demonstrated that positioning the AC in M1 (M1D or M1P) reduced the pulling force exerted by the stent‐retriever on M2 compared with AC placement in the cavernous carotid (NoAsp). The pulling force exerted from pinching the 4x20mm stent with the AC at M1D was higher than with the ingestion technique, for which the explanation is uncertain, but may be due to the additional friction in the M1 segment. Taken together, these findings suggest a combined approach decreases frictional pulling force during stent‐retrieval and is safer than SR alone. We also note that the pulling force of each stent decreased after its third usage, in line with the manufacturer’s instructions for use, which suggest no more than 3 retrievals per stent (3). Future experiments will compare a wider range of techniques using stents of varying sizes to better clarify factors associated with decreased pulling force in EVT.

Introduction: The ADAPT (a direct aspiration first pass technique for acute stroke thrombectomy), using large bore aspiration catheters, has been reported to be a fast, safe, simple and effective method of mechanical thrombectomy (MT) that has facilitated the treatment of acute ischemic strokes. Hypothesis: An attempt to determinate the favorable factors leading to a satisfactory reperfusion (TICI 2b/3) with ADAPT in anterior circulation ischemic stroke patients with confirmed large vessel occlusions. Methods: Based on our prospectively gathered database we extracted patients who were admitted for MT in anterior circulation ischemic strokes since August 2013 and for whom ADAPT was used as the first MT option. Patient demographics, initial NIHSS, localization and lateralization of the occlusion, DWI-ASPECTS, IV thrombolysis prior to MT, time from stroke onset to femoral puncture, final TICI score and 3-month mRS were analyzed. Results: ADAPT was effective in achieving a TICI2b/3 in 54.7% of 309 patients. Two factors influenced positively the success of reperfusion with ADAPT as a stand alone procedure: an isolated MCA occlusion (p&lt;0.0001) and a shorter time from stroke onset to femoral puncture (p=0.0156). Age, Gender, initial NIHSS, DWI-ASPECTS and IV thrombolysis prior to MT did not influence the success of the ADAPT procedure. The additional use of stent retrievers improved the TICI 2b/3 revascularization rate to 84.1% (p&lt;0.0001). When ADAPT was the sole technique used to achieve satisfactory reperfusion, 3-month mRS≤2 was achieved in 70.4% of the patients, while only 41.7% of mRS≤2 at 3-month was achieved in patients for whom ADAPT then stent retrievers were used (p=0.0001). Conclusions: ADAPT is very effective in case of isolated MCA occlusion ischemic strokes. The relevance of ADAPT over stent retrievers in other anterior circulation localizations (carotid siphon and tandem occlusions) has to be evaluated with a randomized study.

PurposeTo report initial experience of A Direct Aspiration first-Pass Thrombectomy (ADAPT) technique using larger bore JET 7 aspiration catheters in patients experiencing acute ischemic stroke secondary to intracranial large vessel...

Background and Aims: Anti-phospholipid syndrome (APS) is characterized by thrombosis and pregnancy complications due to persistent anti-phospholipid antibodies, with stroke being the most common arterial thrombosis. The complement system has emerged as a key factor in APS-related events, offering potential for targeted therapies. Methods: We present the case of a 50-year-old woman diagnosed with APS who suffered a large vessel occlusion despite being on warfarin. Results: The patient has a history of APS with overlap undifferentiated connective tissue disease since 2013, initially presenting with thrombosis of the internal jugular, subclavian, axillary, and left brachial veins, which necessitated the initiation of warfarin therapy. In 2022, she experienced a recurrence of bilateral femoropopliteal deep vein thrombosis with pulmonary embolism after switching from warfarin to Xarelto. Consequently, warfarin was reintroduced, but the patient missed multiple outpatient follow-ups. On January 1, 2025, she visited the Emergency Department (ED) reporting paresthesia on the right side of her body for four days, with an INR of 2.2. A brain CT scan revealed no acute changes, and she was instructed to undergo brain MRI, angioRM, and electroencephalography. On January 27, she returned to the ED with new paresthesia and a fluctuating headache on the left side, with an INR of 2.02, leading to her admission to the Neurology Department. By January 28, she exhibited mild right facial-brachial sensory hemisyndrome (NIHSS2), prompting initiation of a stroke protocol. An MRI with angio-MRI revealed recent ischemic lesions in the left hemisphere, complete occlusion of the left carotid artery, and poor flow in the middle cerebral artery. Cerebral arteriography confirmed reduced calibre and slow flow in the left internal carotid artery. The patient’s condition deteriorated rapidly, presenting with mutism, gaze deviation, right hemiplegia, and VII cranial nerve deficits (NIHSS 20). Intubation was necessary, and a thromboaspiration attempt was unsuccessful. A stent was placed during an IV infusion of cangrelor, but this led to early reocclusion, prompting the administration of aspirin 500 mg IV and continuation of anticoagulation therapy with LMWH. Twelve hours later, control arteriography showed thrombosis of the intracranial stent at the carotid siphon. Given the poor response to anticoagulant and antiplatelet treatment, we initiated therapy with eculizumab 900 mg weekly for four weeks. Twenty-four hours after the second eculizumab infusion, the patient was extubated, showing only mild residual sensorimotor hemisyndrome on the right. A follow-up cerebral MRI with AngioMRI at four weeks demonstrated no pathological enhancement in black blood sequences but revealed moderate stenosis at the carotid siphon and mild stenosis at the origin of the left middle cerebral artery. Three months post-event, after a rehabilitation program, the patient exhibited only mild dysesthesia in her left deltoid region.

Clinical Comparison of New Generation 0.071-inch and 0.072-inch Aspiration Catheters

Aspiration thrombectomy is a widely adopted treatment for acute ischemic stroke due to large vessel occlusion. Among several technical factors, the diameter of the aspiration catheter plays a critical role in determining thrombus fixation, aspiration efficiency, and overall procedural success. This study aimed to investigate the biomechanical effects of a larger catheter diameter on thrombus behavior and vessel wall response during aspiration thrombectomy. Finite element analysis was employed to simulate aspiration using three clinically relevant aspiration catheters with different diameters. Thrombi of two lengths and two compositions, varying in red blood cell content, were modeled to reflect clinical variability. Mechanical outcomes, including thrombus deformation, internal stress distribution, and vessel wall loading, were analyzed under standardized aspiration pressure conditions. 0.080- and 0.084-inch large-bore catheters produced greater thrombus deformation and internal stress than the 0.072-inch catheter, particularly in softer thrombi with higher red blood cell content. In both 3 and 5 mm thrombi with red blood cells, deformation increased by approximately 12.3% with the 0.084-inch catheter compared to the 0.072-inch catheter. These changes indicate improved clot engagement and aspiration efficiency, while vessel stress remained within physiological limits. This mechanical advantage is partly due to greater luminal occupancy, with the 0.084-inch catheter occupying 65.6% of the vessel lumen, about 14% more than the 0.072-inch catheter. Large-bore aspiration catheters can enhance thrombus fixation and aspiration performance without compromising vascular integrity. These findings support the broader clinical use of larger-bore catheters in patients with large artery occlusion, particularly in cases requiring strong clot engagement and efficient recanalization.

Carotid siphon calcification impact on revascularization and outcome in stroke intervention

The value of clot imaging in patients with emergent large vessel occlusion (ELVO) treated with thrombectomy is unknown. We performed retrospective analysis of clot imaging (clot density, perviousness, length, diameter, distance to the internal carotid artery (ICA) terminus and angle of interaction (AOI) between clot and the aspiration catheter) of consecutive cases of middle cerebral artery (MCA) occlusion and its association with first pass effect (FPE, TICI 2c-3 after a first attempt). Patients (n = 90 total) with FPE had shorter clot length (9.9 ± 4.5 mm vs. 11.7 ± 4.6 mm, P = 0.07), shorter distance from ICA terminus (11.0 ± 7.1 mm vs. 14.7 ± 9.8 mm, P = 0.048), higher perviousness (39.39 ± 29.5 vs 25.43 ± 17.6, P = 0.006) and larger AOI (153.6 ± 17.6 vs 140.3 ± 23.5, P = 0.004) compared to no-FPE patients. In multivariate analysis, distance from ICA terminus to clot ≤13.5 mm (odds ratio (OR) 11.05, 95% confidence interval (CI) 2.65-46.15, P = 0.001), clot length ≤9.9 mm (OR 7.34; 95% CI 1.8-29.96, P = 0.005), perviousness ≥ 19.9 (OR 2.54, 95% CI 0.84-7.6, P = 0.09) and AOI ≥ 137°^ (OR 6.8, 95% CI 1.55-29.8, P = 0.011) were independent predictors of FPE. The optimal cut off derived using Youden's index was 6.5. The area under the curve of a score predictive of FPE success was 0.816 (0.728-0.904, P < 0.001). In a validation cohort (n = 30), sensitivity, specificity, positive and negative predictive value of a score of 6-10 were 72.7%, 73.6%, 61.5% and 82.3%. Clot imaging predicts the likelihood of achieving FPE in patients with MCA ELVO treated with the aspiration-first approach.

IntroductionRecent advances in neurovascular devices available for ischemic stroke intervention have led to the routine use of large-bore aspiration catheters (AC) for successful and effective thrombus removal. However, navigation through...

Section Editors: Marc Fisher MD Antoni Davalos MD The Food and Drug Administration (FDA) evaluates applications for new human drugs, biologics, and complex medical devices. Companies must obtain FDA approval to legally market these products. In August, the FDA gave Concentric Medical clearance to market its Merci Retriever system to “remove blood clots from the brain in patients experiencing an ischemic stroke.” Given that the FDA is charged with “protecting the public health by assuring the safety, efficacy, and security of… biological products and medical devices…, ” “advancing public health by helping to speed innovations that make medicines … more effective, safer, and more affordable,” and “helping the public get the accurate, science-based information they need to use medicines … to improve their health,”1 the FDA’s decision to approve the Merci Retriever system is of concern. The pathways to approval are reviewed by Felten et al in the accompanying article and are outlined in Figure 1. Figure 1. Potential pathways for device approval. The decision to approve the Merci Retriever was based on data from the MERCI (Mechanical Embolus Removal in Cerebral Ischemia) Trial; the approval was granted through the 510(k) process. The Merci Retriever system includes a flexible nickel titanium (nitinol) wire that obtains a helical shape once it is passed through the tip of the guidance catheter. In practice, the catheter/wire is passed distal to the thrombus, the catheter is removed, and the helical configuration assumed by the wire; the clot is then trapped in the helix and withdrawn from the vasculature (Figure 2). The 510(k) clearance means that the Merci Retriever was felt to be substantially equivalent to a predicate device. In this case, the predicate device was the Concentric Retriever, which itself received 510(k) clearance by the FDA in May 2001 for “use in …

Purpose To report the efficacy of A Direct Aspiration first-Pass Thrombectomy (ADAPT) technique with evolving ACE aspiration catheter technology as first-line treatment for anterior circulation emergent large vessel occlusions (ELVOs) and assess for the presence of a first pass effect with ADAPT. Methods We retrospectively reviewed 152 consecutive patients with anterior circulation ELVOs treated with the ADAPT technique as first-line treatment using ACE 60, 64 or 68 at our institution. Baseline characteristics, procedural variables, and modified Rankin Scale (mRS) at 90 days were recorded. Results Fifty-seven patients were treated with ACE 60 (37.5%), 35 with ACE 64 (23%) and 60 with ACE 68 (39.5%). Median groin puncture to reperfusion time was 30 min with ACE 60, 26 min with ACE 64, and 19.5 min with ACE 68. Successful reperfusion after the first ADAPT pass was 33% with ACE 60% and 53% with ACE 68 (p=0.04). Of note, successful reperfusion after the first ADAPT pass was achieved in 23 of 33 patients with M1 occlusions treated with ACE 68 in our cohort (69.7%). The stent-retriever rescue rate was 26% with ACE 60, 3% with ACE 64% and 10% with ACE 68 (p=0.004). The rate of embolus to a new territory was 5.3% with ACE 60, 2.9% with ACE 64% and 1.7% with ACE 68 (p=0.5). The rate of intracranial vascular injury was 1.8% with ACE 60, 5.7% with ACE 64% and 5% with ACE 68 (p=0.5). The symptomatic intracranial hemorrhage rate was 1.8% with ACE 60, 5.7% with ACE 64% and 6.7% with ACE 68 (p=0.4). At 90 days, a good clinical outcome, mRS 0–2, was achieved in 70 patients (46.1%), while 27 patients had mRS 3 (17.8%), 22 mRS 4–5 (14.5%), and 33 expired (21.7%). In multivariate logistic regression analysis, use of the ACE 68 aspiration catheter was an independent predictor of successful reperfusion after the first ADAPT pass (p-value 0.016, OR 1.67, 95% CI 1.1–2.54), while successful reperfusion after the first ADAPT pass was an independent predictor of good clinical outcome at 90 days (p-value 0.0004, OR 6.2, 95% CI 2.27–16.8). Conclusion Use of the ACE 68 aspiration catheter was associated with shorter groin puncture to reperfusion times, higher rates of successful reperfusion after the first ADAPT pass, and lower rates of stent-retriever rescue. Further, a first pass effect was demonstrated in our ADAPT patient cohort. Disclosures J. Delgado Almandoz: 2; C; Penumbra, Inc. Y. Kayan: 2; C; Penumbra, Inc. A. Wallace: None. R. Tarrel: None. J. Fease: None. J. Scholz: None. A. Milner: None. P. Roohani: None. M. Mulder: None. M. Young: None.

IntroductionThe ASSIST registry is a prospective, global registry that assessed clinical and procedural outcomes associated with various operator techniques for mechanical thrombectomy (MT) in acute ischemic stroke (AIS) patients with...

Mechanical thrombectomy has become the accepted standard of care in patients with large-vessel occlusions; however, the management of more distal occlusions is more variable. Although often less clinically severe than proximal occlusions, M2 occlusions can cause significant disability, particularly when they occur in the dominant cerebral hemisphere. Recanalization of M2 occlusions with intravenous recombinant tissue plasminogen activator has been reported to be unreliable (only successful in 30.8% of cases).1 Reliable recanalization of M2 occlusions (thrombolysis in cerebral infarction [TICI] grade 2b or 3 in 76.9% of cases) using contemporary endovascular techniques has been reported.2 A multi-institutional experience demonstrated similar radiographic and clinical success rates when comparing direct aspiration and primary stent retrieval to treat M2 occlusions.3 In this video, we present the case of a 62-yr-old woman with a left M2 occlusion treated using the "Solumbra" technique.4 This technique utilizes a stent retriever in conjunction with aspiration, which is achieved by advancing the aspiration catheter adjacent to the clot. The small caliber of the M2 segment prohibits the advancement of the large-bore aspiration catheter into this segment. However, as demonstrated in this video, placement of the aspiration catheter at the M2 ostia with deployment of the stent retriever in the M2 clot can provide effective recanalization. It should be noted that care should be taken when advancing a guide catheter into the petrous carotid artery for support as this is an advanced maneuver and may increase the risk of iatrogenic injury in inexperienced hands. Consent was obtained from the patient prior to performing the procedure. Institutional Review Board approval is not required for the report of a single case.