Primary results from the CLEAR study of a novel stent retriever with drop zone technology.

BACKGROUND: Challenges to revascularization of large vessel occlusions (LVOs) persist. Current stent retrievers have limited effectiveness for removing organized thrombi. The NeVa device is a novel stent retriever designed to capture organized thrombi within the scaffold during retrieval. OBJECTIVE: To evaluate the safety and effectiveness of revascularization of acute LVOs with the NeVa device. METHODS: Prospective, international, multicenter, single-arm, Investigational Device Exemption study to evaluate the performance of the NeVa device in recanalizing LVOs including internal carotid artery, M1/M2 middle cerebral artery, and vertebrobasilar arteries, within 8 hours of onset. Primary endpoint was rate of expanded Treatment in Cerebral Ischemia (eTICI) score 2b-3 within 3 NeVa passes, tested for non-inferiority against a performance goal of 72% with a -10% margin. Additional endpoints included first pass success and 90-day modified Rankin Scale (mRS) score 0-2. Primary composite safety endpoint was 90-day mortality and/or 24-hour symptomatic intracranial hemorrhage (sICH). RESULTS: From April 2021 to April 2022, 139 subjects were enrolled at 25 centers. Median National Institutes of Health Stroke Scale (NIHSS) score was 16 (IQR 12-20). In the primary analysis population (n=107), eTICI 2b-3 within 3 NeVa passes occurred in 90.7% (97/107; non-inferiority P<0.0001; post hoc superiority P<0.0001). First pass eTICI 2b-3 was observed in 73.8% (79/107), with first pass eTICI 2b67-3 in 69.2% (74/107) and eTICI 2c-3 in 48.6% (52/107). Median number of passes was 1 (IQR 1-2). Final eTICI 2b-3 rate was 99.1% (106/107); final eTICI 2b67-3 rate was 91.6% (98/107); final eTICI 2c-3 rate was 72.9% (78/107). Good outcome (90-day mRS score 0-2) was seen in 65.1% (69/106). Mortality was 9.4% (13/138) with sICH in 5.0% (7/139). CONCLUSIONS: The NeVa device is highly effective and safe for revascularization of LVO strokes and demonstrates superior first pass success compared with a predicate performance goal. TRIAL REGISTRATION NUMBER: NCT04514562.

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

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Treatment of a ruptured shallow trilobed cerebral aneurysm with the novel saccular endovascular aneurysm lattice (SEAL) device: A case report with one year follow-up.

Intrasaccular flow disruption is a viable alternative to other endovascular treatments for saccular or wide-necked bifurcation intracranial aneurysms; however, wide neck aneurysms with irregular shapes or shallow depth may not be amenable to treatment currently available intrasaccular devices. Here, we present the first ever case report of the novel Saccular Endovascular Aneurysm Lattice Embolization System (SEAL™). The versatile utility of the SEAL™ device is demonstrated in a patient with acute subarachnoid hemorrhage (SAH) from a ruptured, complex, left middle cerebral artery (MCA) trilobed shallow wide-necked bifurcation aneurysm. Deployment and implantation of the SEAL device were technically feasible, safe, and conformed well to the irregular shape of the complex, ruptured aneurysm. Immediate total aneurysm occlusion was observed after implantation. Importantly, 1-year angiographic follow-up demonstrated durable, complete occlusion with no safety concerns. The SEAL device is a promising new novel technology which has the potential to treat very shallow aneurysms with limited height and irregular, multilobulated aneurysms.

Impact of interhospital transfer vs. direct admission on acute ischemic stroke patients: A subset analysis of the COMPLETE registry.

Background: Efficacy of thrombectomy treatment in acute ischemic stroke large vessel occlusion (AIS-LVO) patients is time dependent. Direct admission to thrombectomy centers (vs. interhospital transfer) may reduce time to treatment and improve outcomes. In this subset analysis of the COMPLETE registry, we compared outcomes between direct to thrombectomy center (Direct) vs. transfer from another hospital to thrombectomy center (Transfer) in AIS-LVO patients treated with aspiration thrombectomy. Methods: COMPLETE was a prospective, international registry that enrolled patients from July 2018 to October 2019, with a 90-day follow-up period that was completed in January 2020. Imaging findings and safety events were adjudicated by core lab and independent medical reviewers, respectively. Pre-defined primary endpoints included post-procedure angiographic revascularization (mTICI ≥2b), 90-day functional outcome (mRS 0-2), and 90-day all-cause mortality. Planned collections of procedural time metrics and outcomes were used in the present post-hoc analysis to compare outcomes between transfer and direct patient cohorts. Results: Of 650 patients enrolled, 343 were transfer [52.8% female; mean (SD) age, 68.2 (13.9) years], and 307 were direct [55.4% female; 68.5 (14.5) years] admit. Median onset-to-puncture time took longer in the transfer vs. direct cohort (5.65 vs. 3.18 h: 2.33 h difference, respectively; p < 0.001). There was no significant difference in successful revascularization rate, mTICI ≥2b (88.3 and 87.3%), sICH at 24 h (3.8 and 3.9%), median length of hospital stay (7 and 6 days), and 90-day mortality (16.9 and 14.0%) between transfer vs. direct patients, respectively. However, achieving 90-day functional independence was less likely in transfer compared with direct patients (mRS 0-2 was 50.3 vs. 61.7%, p = 0.0056). Conclusions: In the COMPLETE registry, direct to thrombectomy center was associated with significantly shorter onset-to-puncture times, and higher rates of good clinical outcome across different geographies. Additional research should focus on AIS-LVO detection to facilitate direct routing of patients to appropriate treatment centers. Clinical trial registration: https://clinicaltrials.gov (Unique identifier: NCT03464565).

Safety and Long-Term Efficacy Outcomes for Endovascular Treatment of Wide-Neck Bifurcation Aneurysms of the Middle Cerebral Artery: Insights From the SMART Registry.

INTRODUCTION: Wide-necked middle cerebral artery bifurcation aneurysms pose specific challenges to endovascular management. Surgical clipping remains the standard treatment approach for these aneurysms in many centers. While recent data suggests the endovascular treatment may be comparable, a prospective datapoint has been lacking. MATERIALS AND METHODS: The Penumbra SMART registry, a prospective, multi-center, single-arm outcomes registry of Penumbra coil-treated aneurysms, was queried for endovascularly treated MCA bifurcation aneurysms with wide necks (dome:neck ratio <2 or neck >4 mm). Safety and efficacy outcomes were summarized for ruptured and unruptured aneurysms, including rupture, complication rate, and 1-year occlusion outcomes. RESULTS: Seventy-two aneurysms across 31 sites were enrolled. Of these, a total of 15 presented as ruptured aneurysms. Serious adverse events were reported in 21 (29.2%) of patients, with 8 (11.1%) attributed to the device/procedure. Immediately postoperatively, 75.0% of cases achieved "adequate" Raymond Roy Class I (40.3%) or II (34.7%) occlusion outcomes. Of the 72 patients treated, 60 (83.3%) underwent follow-up angiography at 1 year, and among these, 95.0% had 1-year occlusion outcomes of Raymond Roy Class I (71.7%) or II (23.3%). A total of 6 aneurysms (10.0%) were required or were planned for retreatment at the last follow-up. CONCLUSION: This study represents the most significant prospective sample of endovascularly treated wide-neck MCA bifurcation aneurysms conducted to date. It supports the safety and efficacy of endovascular treatment of these aneurysms.

POSITIVE: Perfusion imaging selection of ischemic stroke patients for endovascular therapy.

BACKGROUND: The PerfusiOn imaging Selection of Ischemic sTroke patIents for endoVascular thErapy (POSITIVE) trial was designed to evaluate functional outcome in patients with emergent large vessel occlusion (ELVO) presenting within 0-12 hours with pre-specified bifurcated arms of early and late window presentation, who were selected for endovascular thrombectomy with non-vendor specific commercially available perfusion imaging software. Recent trials demonstrating the benefit of thrombectomy up to 16-24 hours following ELVO removed equipoise to randomize late window ELVO patients and therefore the trial was halted. METHODS: Up to 200 patients were to be enrolled in this FDA-cleared, prospective, randomized, multicenter international trial to compare thrombectomy and best medical management in patients with ELVO ineligible for or refractory to treatment with IV tissue plasminogen activator (IV-tPA) selected with perfusion imaging and presenting within 0-12 hours of last seen normal. The primary outcome was 90-day clinical outcome as measured by the raw modified Rankin Scale (mRS) with scores 5 and 6 collapsed (mRS shift analysis). RESULTS: The POSITIVE trial suspended enrollment with the release of results from the DAWN trial and was stopped after the release of the DEFUSE 3 trial results. Thirty-three patients were enrolled (21 for medical management and 12 for thrombectomy). Twelve of the 33 patients were enrolled in the 6-12 hour cohort. Despite the early cessation, the primary outcome demonstrated statistically significant superior clinical outcomes for patients treated with thrombectomy (P=0.0060). The overall proportion of patients achieving an mRS score of 0-2 was 75% in the thrombectomy cohort and 43% in the medical management cohort (OR 4.00, 95% CI 0.84 to 19.2). CONCLUSION: POSITIVE supports the already established practice of delayed thrombectomy for appropriately selected patients presenting within 0-12 hours selected by perfusion imaging from any vendor. The results of the POSITIVE trial are consistent with other thrombectomy trials. The statistically significant effect on functional improvement, despite the small number of patients, reinforces the robust benefits of thrombectomy. CLINICAL TRIAL REGISTRATION: NCT01852201.

Primary results of the Vesalio NeVa VS for the Treatment of Symptomatic Cerebral Vasospasm following Aneurysm Subarachnoid Hemorrhage (VITAL) Study.

BACKGROUND: Cerebral vasospasm (CV) after aneurysmal subarachnoid hemorrhage (aSAH) is linked to worse neurological outcomes. The NeVa VS is a novel cerebral dilation device based on predicate stent retrievers. We report the results of the Vesalio NeVa VS for the Treatment of Symptomatic Cerebral Vasospasm following aSAH (VITAL) Study. METHODS: This was a single-arm prospective multicenter trial to assess the safety and probable benefit of the NeVa VS device to treat CV. Patients were screened and treated if they had CV >50% on non-invasive imaging confirmed by cerebral angiography. The vessel diameters were measured before and after treatment by an independent core laboratory. The primary endpoint was ≥50% vessel diameter immediately after treatment with the NeVa VS device. RESULTS: Thirty patients with a mean age of 52±11 years and mean Hunt-Hess grade of 3.1±0.9 were enrolled. A total of 74 vessels were treated with an average of 1.3 deployments per vessel (95 deployments total). The mean pre-treatment narrowing of the target vessel (n=74) was 65.6% with reduction of the narrowing to 29.4% after treatment. The primary endpoint was achieved in 64 of 74 vessels (86.5%). In three of 95 total deployments (3.2%), thrombus at the site of deployment was observed during the procedure without apparent neurological sequelae. CONCLUSIONS: The NeVa VS device appears to be a safe treatment to regain vessel diameter in severely narrowed intracranial arteries secondary to CV associated with aSAH. This treatment offers a new tool that allows for controlled vessel expansion to treat CV.

Intravenous alteplase has different effects on the efficacy of aspiration and stent retriever thrombectomy: analysis of the COMPASS trial.

BACKGROUND: There is conflicting evidence on the utility of intravenous (IV) alteplase in patients with emergent large vessel occlusion (ELVO) treated with mechanical thrombectomy (MT). METHODS: This was a post hoc analysis of the COMPASS: a trial of aspiration thrombectomy versus stent retriever thrombectomy as first-line approach for large vessel occlusion. We compared clinical, procedural and angiographic outcomes of patients with and without prior IV alteplase administration. RESULTS: In the COMPASS trial, 235 patients had presented to the hospital within the first 4 hours of stroke symptom onset and were eligible for analysis. On univariate analysis, administration of IV alteplase prior to MT was found to be significantly associated with favorable outcomes (modified Rankin scale (mRS) 0-2 at 3 months; 55.6% vs 40.0% in the MT-only group, P=0.037). However, on multivariate analysis, only baseline (pre-stroke) mRS, admission National Institutes of Health Stroke Scale (NIHSS) score and age were identified as independent predictors of favorable outcomes at 3 months. We found higher final thrombolysis in cerebral infarction (TICI) 2b/3 rates in patients without the use of alteplase prior to the aspiration first approach (100.0% vs 87.9% in IV altepase +aspiration first MT, P=0.03). In the stent retriever first group, final TICI 2b/3 rates were identical in patients with and without IV alteplase administration (87.5% and 87.5%, P=1.0). CONCLUSIONS: Prior administration of IV alteplase may adversely affect the efficacy of aspiration, but does not seem to influence the stent retriever first approach to MT in patients with anterior circulation ELVO.

Endovascular Treatment of Acute Ischemic Stroke With the Penumbra System in Routine Practice: COMPLETE Registry Results.

BACKGROUND AND PURPOSE: The purpose of the COMPLETE (International Acute Ischemic Stroke Registry With the Penumbra System Aspiration Including the 3D Revascularization Device) registry was to evaluate the generalizability of the safety and efficacy of the Penumbra System (Penumbra, Inc, Alameda) in a real-world setting. METHODS: COMPLETE was a global, prospective, postmarket, multicenter registry. Patients with large vessel occlusion-acute ischemic stroke who underwent mechanical thrombectomy using the Penumbra System with or without the 3D Revascularization Device as frontline approach were enrolled at 42 centers (29 United States, 13 Europe) from July 2018 to October 2019. Primary efficacy end points were successful postprocedure angiographic revascularization (modified Thrombolysis in Cerebral Infarction ≥2b) and 90-day functional outcome (modified Rankin Scale score 0-2). The primary safety end point was 90-day all-cause mortality. An imaging core lab determined modified Thrombolysis in Cerebral Infarction scores, Alberta Stroke Program Early CT Scores, clot location, and occurrence of intracranial hemorrhage at 24 hours. Independent medical reviewers adjudicated safety end points. RESULTS: Six hundred fifty patients were enrolled (median age 70 years, 54.0% female, 49.2% given intravenous recombinant tissue-type plasminogen activator before thrombectomy). Rate of modified Thrombolysis in Cerebral Infarction 2b to 3 postprocedure was 87.8% (95% CI, 85.3%-90.4%). First pass and postprocedure rates of modified Thrombolysis in Cerebral Infarction 2c to 3 were 41.5% and 66.2%, respectively. At 90 days, 55.8% (95% CI, 51.9%-59.7%) had modified Rankin Scale score 0 to 2, and all-cause mortality was 15.5% (95% CI, 12.8%-18.3%). CONCLUSIONS: Using Penumbra System for frontline mechanical thrombectomy treatment of patients with large vessel occlusion-acute ischemic stroke in a real-world setting was associated with angiographic, clinical, and safety outcomes that were comparable to prior randomized clinical trials with stringent site and operator selection criteria. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03464565.

Clot perviousness is associated with first pass success of aspiration thrombectomy in the COMPASS trial.

BACKGROUND: Clot density (Hounsfield units, HU) and perviousness (post-contrast increase in the HU of clot) are thought to be associated with clot composition. We evaluate whether these imaging characteristics were associated with angiographic outcomes of aspiration and stent retriever thrombectomy in COMPASS: a trial of aspiration thrombectomy versus stent retriever thrombectomy as first-line approach for large vessel occlusion. METHODS: Clot density and perviousness were measured by two independent operators who were blind to all the final angiographic and clinical outcomes. The association of clot density and perviousness with the Thrombolysis In Cerebral Infarction (TICI) scale after first pass was assessed using univariate and multivariate analysis. RESULTS: Among all patients enrolled in COMPASS, 165 were eligible for the post-hoc analysis (81 patients in the aspiration first and 84 in the stent retriever first groups). Overall mean perviousness of clot was significantly higher in patient with mTICI 2b-3 after first pass (28.6±22.9 vs 20.3±19.2, p=0.017). Mean perviousness among patients who achieved TICI 2c/3 versus TICI 2b versus TICI 0-2a in the aspiration first group varied significantly (32.6±26.1, 35.3±24.4, and 17.7±13.1, p=0.013). The association of perviousness with first pass success was not significant in the stent retriever group. Using multivariate analysis, high perviousness (defined as cut-off >27.6) was an independent predictor of TICI 2b-3 (OR 3.82, 95% CI 1.10 to 13.19; p=0.034). CONCLUSIONS: Clot perviousness is associated with first pass angiographic success in patients treated with the aspiration first approach for thrombectomy.

An international multicenter retrospective study to survey the landscape of thrombectomy in the treatment of anterior circulation acute ischemic stroke: outcomes with respect to age.

BACKGROUND: Thrombectomy is an efficacious treatment for acute ischemic stroke (AIS). However, relatively few studies to date have specifically examined the impact and clinical implications of age on outcomes for thrombectomy in anterior AIS. OBJECTIVE: To provide a snapshot of patient metrics and outcomes with respect to age following thrombectomy for anterior AIS to supplement the current body of data for predictors of clinical outcomes in a real-world setting. METHODS: Data were collected for 20 consecutive patients with AIS treated with thrombectomy at 15 high-volume stroke centers across North America between 2015 and 2016. Patients with anterior occlusions were dichotomized based on whether they were older or younger than 80 years. Ordinal logistic regression analyzed how clinical variables impacted disability using 90-day modified Rankin Scale (mRS) scores. RESULTS: Adequate revascularization (TICI ≥2B) was achieved in 92.3% of patients aged <80 years with an average 1.7±0.1 passes taken with the primary technique and in 88.0% of patients aged ≥80 years with an average 1.7±0.2 passes. Despite similar baseline characteristics, mRS scores were significantly higher in older patients postoperatively and at 90 days after intervention. Age was a significant predictor of 90-day mRS across the study population. CONCLUSION: This analysis affirms age is a significant determinant of 90-day mRS scores following thrombectomy for large vessel anterior AIS. Further investigation into risks faced by elderly patients during thrombectomy may provide actionable information to help refine patient selection and improve outcomes.

'Real-world' comparison of first-line direct aspiration and stent retriever mechanical thrombectomy for the treatment of acute ischemic stroke in the anterior circulation: a multicenter international retrospective study.

BACKGROUND: Thrombectomy for anterior large vessel occlusion less than 24 hours since last known well is now standard of care. Certain aspects of clinical trials may limit generalizability to 'real-world' practice. OBJECTIVE: To compare revascularization rates and outcomes for direct aspiration (ADAPT) and stent retriever thrombectomy following anterior acute ischemic stroke (AIS) in a real-life setting. METHODS: Data from the most recent 20 consecutive patients with AIS treated with mechanical thrombectomy between 2015 and 2016 were collected from 15 high-volume stroke centers across North America for a total of 300 cases. Patients with proximal anterior large vessel occlusions were dichotomized by primary treatment technique. Ordinal logistic regression assessed the effects of clinical variables on patient disability using 90-day modified Rankin Scale (mRS) scores. RESULTS: Adequate revascularization (Thrombolysis in Cerebral Infarction ≥2b) was ultimately achieved in 91.2% of first-line direct aspiration (ADAPT) cases with an average of 1.9±1.9 passes and in 87.5% of stent retriever cases with an average of 1.7±1.0 passes. Time from groin puncture to revascularization was shorter for ADAPT cases. The mean 90-day mRS score for both groups was 3.0±2.4. Number of passes using primary technique, and postintervention intracranial hemorrhage, were significant predictors of 90-day mRS scores after ADAPT, while age and preprocedure mRS score were predictive of outcomes following first-line stent retriever. CONCLUSIONS: Our data show similar adequate revascularization rates and 90-day functional outcomes for first-line direct aspiration and stent retrievers for anterior large vessel occlusion in a real-world setting. These results support the findings of other prospective trials evaluating the two techniques.

The Dotter method revisited: early experience with a novel method of rapid internal carotid artery revascularization in the setting of acute ischemic stroke.

BACKGROUND: Tandem occlusive disease in the setting of acute ischemic stroke involving cervical and cerebral arteries has been associated with poor neurological outcome and poses significant challenges to neurointerventionists. Previously described endovascular methods typically involve carotid revascularization with stent placement prior to or following intracranial thrombectomy. Stent-based approaches, however, require the use of antiplatelet therapy which may increase the risk of hemorrhagic transformation. We describe a novel modified Dotter technique which may be used for carotid revascularization in lieu of stenting. This technique can eliminate the need for antiplatelet therapy, reduce procedure times, and possibly reduce hemorrhagic conversion rates. METHODS: Seven patients presenting between April 2013 and January 2014 were treated with this technique. All patients had carotid stenosis of 65-100% and tandem middle cerebral artery occlusions. National Institutes of Health (NIH) Stroke Scale scores as well as clinical and procedural times were recorded. Pre- and post-Dotter stenosis was measured using the NASCET criteria. Follow-up imaging and clinical data were reviewed. RESULTS: The mean age was 64 years and mean initial NIH Stroke Scale score was 11.7. Mean groin to recanalization time was 26 min. Thrombolysis In Cerebral Infarction grade 2b-3 was achieved in all patients. The mean stenosis was 88% preoperatively and 61% postoperatively. There were no intracranial hemorrhages. The modified Rankin Scale score was 0 in six patients (86%) and 6 in one patient (14%). CONCLUSIONS: The Dotter stroke technique is a feasible and safe alternative to carotid stenting in the setting of acute ischemic stroke and may reduce the risk of hemorrhagic conversion. No re-occlusion occurred during follow-up in patients with post-Dotter stenosis ≤65%.

AngioSuite: an accurate method to calculate aneurysm volumes and packing densities.

OBJECTIVE: AngioSuite was developed to allow the easy and accurate calculation of cerebral aneurysm volumes and packing densities. The present study was undertaken to validate its accuracy. METHODS: Mathematical models and software were created to facilitate more complex aneurysm volume calculations than previously described three-dimensional geometric models. 20 phantom aneurysm clay models were created and analyzed (length, width, depth and volume) using angiographic mathematical modeling (AngioSuite), geometric modeling (AngioCalc) and three-dimensional volume reconstructions from the vendor's Leonardo workstation (Siemens). RESULTS: The mean volumes of all phantoms analyzed by the AngioSuite system differed from true volumes by an average of 2.2%. Mean volumes of all phantoms analyzed by the AngioCalc system differed from true volumes by an average of 11.3%. Mean volumes obtained from the Leonardo workstation windowed for best appearance differed by an average of 5.18%. CONCLUSIONS: The AngioSuite software system provides an accurate means of calculating aneurysm volumes. Typical packing densities (40% or less) are thus accurate within ±1%. Angiographic mathematical modeling with AngioSuite is more accurate than geometric modeling and three-dimensional volume reconstructions windowed for best appearance (Leonardo).