AXS Vecta 0.071–0.074 Inch Aspiration Catheters for Mechanical Thrombectomy: Case Series and Literature Review

Aspiration catheters are widely used for thrombectomy either alone or in combination with a stent-retriever, with a distal inner diameter and trackability keys to their success. In an illustrative case series, we report our clinical experience with AXS Vecta (Stryker Neurovascular, Fremont, CA, USA), available in both 0.071-inch and 0.074-inch distal inner diameters, including the first 2 Vecta 74 cases reported. A literature review on AXS Vecta is also provided. In our series, 9 thrombectomies were performed (Vecta 71: 2 M1, 5 M2 occlusions; Vecta 74: 1 M1 and 1 ICA-terminus occlusion). The AXS Vecta was successfully delivered to the target site in all cases. In 7 of 9 cases, the catheter was delivered over a Tenzing 7 delivery catheter (Route 92 Medical, San Mateo, CA, USA). For 2 of 9 combination approach cases, Vecta was delivered using the stent-retriever wire as a rail. The median improvement in NIHSS score during hospitalization was 9 (IQR 5–12). Successful mTICI 2C or 3 recanalization was achieved in 8 of 9 (89%) patients after a median 2 (IQR 1–2) passes. Our median groin-to-reperfusion time was 23 (IQR 12.5–32) minutes, with no procedural complications. Two previous clinical studies of a total of 29 patients treated with Vecta 71 reported successful mTICI 2b–3 recanalization in 89–90% of cases. The Median groin-to-reperfusion time was 30 minutes. Complications were seen in 2 of 29 (6.9%) cases (vessel perforation and/or intracerebral hemorrhage). These data support the efficacy, deliverability, and safety of AXS Vecta for mechanical thrombectomy

Interhospital Transfer Before Thrombectomy Is Associated With Delayed Treatment and Worse Outcome in the STRATIS Registry (Systematic Evaluation of Patients Treated With Neurothrombectomy Devices for Acute Ischemic Stroke).

BACKGROUND: Endovascular treatment with mechanical thrombectomy (MT) is beneficial for patients with acute stroke suffering a large-vessel occlusion, although treatment efficacy is highly time-dependent. We hypothesized that interhospital transfer to endovascular-capable centers would result in treatment delays and worse clinical outcomes compared with direct presentation. METHODS: STRATIS (Systematic Evaluation of Patients Treated With Neurothrombectomy Devices for Acute Ischemic Stroke) was a prospective, multicenter, observational, single-arm study of real-world MT for acute stroke because of anterior-circulation large-vessel occlusion performed at 55 sites over 2 years, including 1000 patients with severe stroke and treated within 8 hours. Patients underwent MT with or without intravenous tissue plasminogen activator and were admitted to endovascular-capable centers via either interhospital transfer or direct presentation. The primary clinical outcome was functional independence (modified Rankin Score 0-2) at 90 days. We assessed (1) real-world time metrics of stroke care delivery, (2) outcome differences between direct and transfer patients undergoing MT, and (3) the potential impact of local hospital bypass. RESULTS: A total of 984 patients were analyzed. Median onset-to-revascularization time was 202.0 minutes for direct versus 311.5 minutes for transfer patients ( CONCLUSIONS: In this large, real-world study, interhospital transfer was associated with significant treatment delays and lower chance of good outcome. Strategies to facilitate more rapid identification of large-vessel occlusion and direct routing to endovascular-capable centers for patients with severe stroke may improve outcomes. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT02239640

MR fluoroscopy in vascular and cardiac interventions (review)

Vascular and cardiac disease remains a leading cause of morbidity and mortality in developed and emerging countries. Vascular and cardiac interventions require extensive fluoroscopic guidance to navigate endovascular catheters. X-ray fluoroscopy is considered the current modality for real time imaging. It provides excellent spatial and temporal resolution, but is limited by exposure of patients and staff to ionizing radiation, poor soft tissue characterization and lack of quantitative physiologic information. MR fluoroscopy has been introduced with substantial progress during the last decade. Clinical and experimental studies performed under MR fluoroscopy have indicated the suitability of this modality for: delivery of ASD closure, aortic valves, and endovascular stents (aortic, carotid, iliac, renal arteries, inferior vena cava). It aids in performing ablation, creation of hepatic shunts and local delivery of therapies. Development of more MR compatible equipment and devices will widen the applications of MR-guided procedures. At post-intervention, MR imaging aids in assessing the efficacy of therapies, success of interventions. It also provides information on vascular flow and cardiac morphology, function, perfusion and viability. MR fluoroscopy has the potential to form the basis for minimally invasive image–guided surgeries that offer improved patient management and cost effectiveness

Abstract 059: The Tenzing‐Dotter Technique for Endovascular Management of Atherosclerotic Cervical ICA Tandem Large Vessel Occlusions

Introduction The endovascular treatment of acute ischemic stroke due to atherosclerotic occlusion/near‐occlusion of the cervical internal carotid artery (ICA) and a concurrent intracranial large vessel occlusion (LVO) remains challenging, and the optimal approach remains unclear. Options include initial angioplasty and/or stenting of the cervical lesion followed by intracranial thrombectomy versus Dotter navigation of catheters through the cervical lesion to first target the intracranial LVO. We describe a novel Tenzing‐Dotter technique which utilizes a Tenzing device for the Dotter delivery of large bore (0.070”) and super‐large bore (0.088”) catheters through cervical atherosclerotic lesions to gain access to the intracranial circulation in tandem LVO patients. Methods We performed a retrospective review our single center experience of atherosclerotic tandem occlusion patients in which the Route 92 Medical Tenzing ® 7 (T7®) and Tenzing ® 8 (T8®) delivery catheters were used to Dotter‐deliver large bore or super‐large bore catheters, respectively, through the cervical ICA lesion to gain access to the intracranial circulation. We reviewed clinical, radiographic and procedural data to describe the safety and efficacy of this approach. Results Twenty patients were identified that that atherosclerotic occlusion/near‐occlusion of the cervical ICA and a single symptomatic intracranial LVO. The mean age was 65 (44 – 89), and 40% were female. The mean NIHSS was 14 (7‐25) and 40% were treated initially with intravenous thrombolytics. The ipsilateral cervical ICA was occluded in 11 of 20 patients (55%) and nearly‐occluded (degree of stenosis 90‐99%) in 9 of 20 patients (45%). The intracranial occlusions were carotid terminus (5), M1 middle cerebral artery (14) and M2 middle cerebral artery (1). Seven patients were treated with Tenzing 7 paired with a large bore catheter (6 with Medtronic React 71 and 1 with Route 92 Medical Hipoint 70), while 13 were treated with Tenzing 8 paired with a super‐large bore catheter (11 with Route 92 Medical Hipoint 88 catheter and 2 with Route 92 Medical Freeclimb 88 catheter). In all cases, successful navigation of the paired catheter through the cervical lesion was achieved in 100% of patient using the Tenzing‐Dotter delivery technique. The mean time from groin puncture to successful Tenzing‐Dotter delivery was 11 minutes, and the mean time from groin puncture to device delivery to the intracranial occlusion was 15 minutes. TICI 2B or greater reperfusion (self‐adjudicated) as achieved in 100% of patients, with a mean time to best TICI of 21 minutes. The degree of cervical ICA stenosis following thrombectomy improved from 96.5% to 67.4%. No symptomatic intracranial hemorrhage or cervical arterial dissections were noted. Conclusion The Tenzing‐Dotter technique, in which a Route 92 Medical Tenzing ® delivery catheter is utilized to Dotter navigate a large or super‐large bore catheter through an occluded or nearly‐occluded cervical atherosclertotic lesion, may be a promising technique for safe and fast access to the intracranial circulation in patients presenting with tandem large vessel occlusion acute ischemic strokes

Abstract Number ‐ 172: First‐in‐Human Experience: Route 92 Medical 132 cm FreeClimb 88 Catheter for Anterior Circulation LVOs

Introduction Direct aspiration thrombectomy of proximal anterior circulation large vessel occlusions (LVOs) with super‐bore catheters (SBCs, 0.088” ID) may result in improved first pass success, though their consistent delivery to the target occlusion remains challenging. We report the first‐in‐human experience with a novel full‐length 132 cm 0.088” ID FreeClimb ® 88 catheter (Route 92 Medical, San Mateo, CA, currently approved for neurovascular access), and its customized Tenzing ® 8 delivery catheter, for anterior circulation LVO acute stroke patients. Methods We performed a retrospective review of thrombectomy cases for proximal anterior circulation large vessel occlusions performed at three stroke centers from May 2022 through August 2022. All patients were treated using the Route 92 Medical 8F Base Camp® guide catheter, FreeClimb ® 88 catheter and Tenzing ® 8 delivery catheter in an off‐label fashion. Results Ten consecutive acute stroke patients with anterior circulation LVOs were treated. The median age was 71 (45‐91) and 6 were female (60%). The median presenting NIHSS score and ASPECT score were 17 (8‐24) and 9 (6‐10), respectively. LVO locations were as follows: two right carotid termini, three right M1 middle cerebral arteries, and five left M1 middle cerebral arteries. Three patients also had tandem occlusion/near‐occlusion of the respective cervical internal carotid artery. The FC88 catheter was delivered to the target occlusion with 100% success. The median time from groin puncture to catheter delivery to the target occlusion was 14 minutes (7‐35). First pass complete reperfusion (modified Thrombolysis in Cerebral Infarction score, mTICI, of 3) was achieved in 9/10 (90%) patients (self‐adjudicated). Adjunctive therapy for a residual M2 occlusion was utilized in 1/10 patients. There were no adverse events or post‐procedural symptomatic hemorrhages. Conclusions Our first‐in‐human experience with a novel 132 cm full‐length super‐bore catheter (Route 92 FreeClimb ® 88 catheter) and its customized catheter delivery device (Tenzing ® 8) for aspiration thrombectomy of proximal anterior circulation large vessel occlusions demonstrated 100% successful delivery to the target occlusion, with TICI 3 first pass reperfusion achieved in 90% of patients

Improvement in intensive care unit outcomes in patients with subarachnoid hemorrhage after initiation of neurointensivist co-management

OBJECT: Neurointensivists are specialists trained to manage all aspects of the intensive care unit (ICU) stay of neurologically ill patients. No study to date has examined the role of neurointensivists specifically in subarachnoid hemorrhage (SAH) management. This study examined the use of a team-based neurointensivist co-management approach. METHODS: The authors reviewed all cases involving patients with SAH admitted to the neurosurgical service during a period of more than 4 years. A comparison was made between those patients admitted before and those admitted after the initiation of a mandatory neurointensivist co-management strategy. The primary outcome examined was length of ICU stay. Secondary outcomes included in-hospital mortality, ventriculoperitoneal shunt placement, and other complications such as fever, antibiotic use, pressor utilization, and ventilator-associated pneumonia. RESULTS: A total of 512 patients were included, 216 prior to and 296 after the initiation of neurointensivist comanagement. Length of ICU stay was significantly decreased after the initiation of neurointensivist co-management (mean 12.4 vs 10.9 days, p = 0.02), even after adjusting for demographic characteristics and admission Hunt and Hess grade. The percentage of patients requiring a ventriculoperitoneal shunt significantly decreased after initiation of the co-management approach (23.0 vs 11.5%, p = 0.001), but in-house mortality was unaffected. CONCLUSIONS: Initiation of a strategy of routine involvement of a neurointensivist, charged with managing all aspects of the patients\u27 care, resulted in a significantly reduced length of ICU stay for neurosurgical SAH patients. This team-based approach, using neurointensivists to manage neurosurgical SAH patients, merits further study as a successful model of care

Bilateral cervical spinal dural arteriovenous fistulas with intracranial venous drainage mimicking a foramen magnum dural arteriovenous fistula.

We describe a unique case of bilateral cervical spinal dural arteriovenous fistulas mimicking an intracranial dural arteriovenous fistula near the foramen magnum. We review its detection via MRI and digital subtraction angiography and subsequent management through surgical intervention. Pitfalls in diagnostic angiography are discussed with reference to accurate location of the fistula site. The venous anastomotic connections of the posterior midline spinal vein to the medial posterior medullary vein, posterior fossa bridging veins, and dural venous sinuses of the skull base are discussed with reference to problem-solving in this complex case. The mechanism of myelopathy through venous hypertension produced by spinal dural fistulas is also emphasized

Spinal dural arteriovenous fistulas and intrathecal venous drainage: correlation between digital subtraction angiography, magnetic resonance imaging, and clinical findings

OBJECT: Spinal dural arteriovenous fistulas (SDAVFs) cause myelopathy through arterialization of the perimedullary venous plexus and venous congestion of the spinal cord. The authors hypothesized that the craniocaudal extent of engorgement of intrathecal draining veins between the fistula site and the point of drainage out of the thecal sac correlates with the degree of myelopathy. METHODS: A retrospective review of the authors\u27 institution\u27s radiology databases identified 31 patients with SDAVFs who had undergone digital subtraction angiography (DSA) and MRI examinations of the spine. The authors counted the number of vertebral body levels of spinal cord enhancement and intrathecal vessel enhancement on T1-weighted postcontrast MRI studies. They also counted the number of levels of cord hyperintensity and intrathecal flow voids on T2-weighted MRI studies. On DSA, the authors identified the number of vertebral body levels of dilated intrathecal draining veins and outflow points from intrathecal veins to epidural veins. Functional status of the patients at the time of diagnosis was assessed using the Aminoff-Logue scale (ALS). RESULTS: Enlargement of the intrathecal draining veins averaged 10 ± 7.7 spinal levels on DSA. Patients with enlarged draining veins extending 10 or more spinal levels on DSA had worse ALS scores (mean gait 3.4, mean micturition 1.5) than patients with draining veins extending fewer than 10 levels (mean gait 1.8, mean micturition 0.6; p = 0.009 and 0.02, respectively). The number of vertebral body levels of enlarged draining veins correlated with the ALS score (gait r = 0.42, p = 0.009; and micturition r = 0.55, p = 0.0006). More extensive enlarged draining veins were associated with more spinal cord T2 hyperintensity, T2 intrathecal flow voids, and T1 vessel enhancement but not cord enhancement. CONCLUSIONS: The craniocaudal extent of enlarged intrathecal veins draining SDAVF correlates with patient functional status, providing further insight into the pathophysiology of venous hypertensive myelopathy