Abstract only 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.
Can lysability of large vessel thrombi in acute ischemic stroke be predicted by measuring clot density on admission nonenhanced CT (NECT), postcontrast enhanced CT, or CT angiogram (CTA)?
We ...retrospectively studied 90 patients with acute large vessel ischemic strokes treated with intravenous (IV) tPA, intra-arterial (IA) tPA, and/or mechanical thrombectomy devices. Clot density in Hounsfield unit (HU) was measured on NECT, postcontrast enhanced CT, and CTA. Recanalization was assessed by the Thrombolysis in Cerebral Infarction grading system (TICI) on digital subtraction angiography.
Thrombus density on preintervention NECT correlated with postintervention TICI grade regardless of pharmacological (IV tPA r=0.69, IA tPA r=0.72, P<0.0001) or mechanical treatment (r=0.73, P<0.0001). Patients with TICI≥2 demonstrated higher HU on NECT (mean corrected HU IV tPA=1.58, IA tPA=1.66, mechanical treatment=1.7) compared with patients with TICI<2 (IV tPA=1.39, IA tPA=1.4, mechanical treatment=1.3) (P=0.01, 0.006, <0.0001 respectively). There was no association between recanalization and age, sex, baseline National Institute of Health Stroke Scale, treatment method, time to treatment, or clot volume.
Thrombi with lower HU on NECT appear to be more resistant to pharmacological lysis and mechanical thrombectomy. Measuring thrombus density on admission NECT provides a rapid method to analyze clot composition, a potentially useful discriminator in selecting the most appropriate reperfusion strategy for an individual patient.
Acute ischemic stroke due to large vessel occlusion (LVO)-vertebral, basilar, carotid terminus, middle and anterior cerebral arteries-likely portends a worse prognosis than stroke unassociated with ...LVO. Because little prospective angiographic data have been reported on a cohort of unselected patients with stroke and with transient ischemic attack, the clinical impact of LVO has been difficult to quantify.
The Screening Technology and Outcome Project in Stroke Study is a prospective imaging-based study of stroke outcomes performed at 2 academic medical centers. Patients with suspected acute stroke who presented within 24 hours of symptom onset and who underwent multimodality CT/CT angiography were approached for consent for collection of clinical data and 6-month assessment of outcome. Demographic and clinical variables and 6-month modified Rankin Scale scores were collected and combined with blinded interpretation of the CT angiography data. The OR of each variable, including occlusion of intracranial vascular segment in predicting good outcome and 6-month mortality, was calculated using univariate and multivariate logistic regression.
Over a 33-month period, 735 patients with suspected stroke were enrolled. Of these, 578 were adjudicated as stroke and 97 as transient ischemic attack. Among patients with stroke, 267 (46%) had LVO accounting for the stroke and 13 (13%) of patients with transient ischemic attack had LVO accounting for transient ischemic attack symptoms. LVO predicted 6-month mortality (OR, 4.5; 95% CI, 2.7 to 7.3; P<0.001). Six-month good outcome (modified Rankin Scale score <or=2) was negatively predicted by LVO (0.33; 0.24 to 0.45; P<0.001). Based on multivariate analysis, the presence of basilar and internal carotid terminus occlusions, in addition to National Institutes of Health Stroke Scale and age, independently predicted outcome.
Large vessel intracranial occlusion accounted for nearly half of acute ischemic strokes in unselected patients presenting to academic medical centers. In addition to age and baseline stroke severity, occlusion of either the basilar or internal carotid terminus segment is an independent predictor of outcome at 6 months.
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.
Efficient and timely recanalization is an important goal in acute stroke endovascular therapy. Several studies demonstrated improved recanalization and clinical outcomes with the stent retriever ...devices compared with the Merci device. The goal of this study was to evaluate the role of the balloon guide catheter (BGC) and recanalization success in a substudy of the North American Solitaire Acute Stroke (NASA) registry.
The investigator-initiated NASA registry recruited 24 clinical sites within North America to submit demographic, clinical, site-adjudicated angiographic, and clinical outcome data on consecutive patients treated with the Solitaire Flow Restoration device. BGC use was at the discretion of the treating physicians.
There were 354 patients included in the NASA registry. BGC data were reported in 338 of 354 patients in this subanalysis, of which 149 (44%) had placement of a BGC. Mean age was 67.3±15.2 years, and median National Institutes of Health Stroke Scale score was 18. Patients with BGC had more hypertension (82.4% versus 72.5%; P=0.05), atrial fibrillation (50.3% versus 32.8%; P=0.001), and were more commonly administered tissue plasminogen activator (51.6% versus 38.8%; P=0.02) compared with patients without BGC. Time from symptom onset to groin puncture and number of passes were similar between the 2 groups. Procedure time was shorter in patients with BGC (120±28.5 versus 161±35.6 minutes; P=0.02), and less adjunctive therapy was used in patients with BGC (20% versus 28.6%; P=0.05). Thrombolysis in cerebral infarction 3 reperfusion scores were higher in patients with BGC (53.7% versus 32.5%; P<0.001). Distal emboli and emboli in new territory were similar between the 2 groups. Discharge National Institutes of Health Stroke Scale score (mean, 12±14.5 versus 17.5±16; P=0.002) and good clinical outcome at 3 months were superior in patients with BGC compared with patients without (51.6% versus 35.8%; P=0.02). Multivariate analysis demonstrated that the use of BGC was an independent predictor of good clinical outcome (odds ratio, 2.5; 95% confidence interval, 1.2-4.9).
Use of a BGC with the Solitaire Flow Restoration device resulted in superior revascularization results, faster procedure times, decreased need for adjunctive therapy, and improved clinical outcome.
Previous work that predated the availability of the safer stent-retriever devices has suggested that general anesthesia (GA) may have a negative impact on outcomes in patients with acute ischemic ...stroke undergoing endovascular therapy.
We reviewed demographic, clinical, procedural (GA versus local anesthesia LA, etc), and site-adjudicated angiographic and clinical outcomes data from consecutive patients treated with the Solitaire FR device in the investigator-initiated North American SOLITAIRE Stent-Retriever Acute Stroke (NASA) Registry. The primary outcomes were 90-day modified Rankin Scale, mortality, and symptomatic intracranial hemorrhage.
A total of 281 patients from 18 centers were enrolled. GA was used in 69.8% (196/281) of patients. Baseline demographic and procedural factors were comparable between the LA and GA groups, except the former demonstrated longer time-to-groin puncture (395.4±254 versus 337.4±208 min; P=0.04), lower National Institutes of Health Stroke Scale (NIHSS; 16.2±5.8 versus 18.8±6.9; P=0.002), lower balloon-guide catheter usage (22.4% versus 49.2%; P=0.0001), and longer fluoroscopy times (39.5±33 versus 28±22.8 min; P=0.008). Recanalization (thrombolysis in cerebral infarction ≥2b; 72.94% versus 73.6%; P=0.9) and rate of symptomatic intracranial hemorrhage (7.1% versus 11.2%; P=0.4) were similar but modified Rankin Scale ≤2 was achieved in more LA patients, 52.6% versus 35.6% (odds ratio, 1.4 1.1-1.8; P=0.01). In multivariate analysis, hypertension, NIHSS, unsuccessful revascularization, and GA use (odds ratio, 3.3 1.6-7.1; P=0.001) were associated with death. When only anterior circulation and elective GA patients were included, there was a persistent difference in good outcomes in favor of LA patients (50.7% versus 35.5%; odds ratio, 1.3 1.01-1.6; P=0.04).
The NASA Registry has demonstrated that clinical outcomes and survival are significantly better in patients treated with LA, without increased symptomatic intracranial hemorrhage risk. Future trials should prospectively evaluate the effect of GA on outcomes.
Background Early clinical experience with the Tenzing 7 delivery catheter (T7, Route 92 Medical, San Mateo, CA, USA) demonstrates high success rates for intracranial delivery of large bore aspiration ...catheters. Its soft, flexible, tapered tip mitigates the “ledge effect” that may cause resistance when navigating neurovascular devices through tortuous internal carotid arteries (ICAs) or other arterial branch origin variants. This study aims to characterize T7 performance across ICAs with varying tortuosities. Methods A retrospective analysis was performed of prospectively collected data from patients with acute ischemic stroke treated with aspiration thrombectomy using T7 between January 2020 and July 2022 at 3 stroke centers. The ICA tortuosity index (TI) was derived from the ratio of actual to straight length measurements from anterior‐posterior and lateral projections during digital subtraction angiography. T7 success is defined as delivering the aspiration catheter to the face of the occlusion. Regression analysis between TI and T7 success was performed. Correlations were calculated between TI, ICA grading, puncture‐to‐reperfusion time, number of passes, and final modified Treatment in Cerebral Infarction score. Significance was P ≤ $ \le $ 0.05. Results Of 107 patients meeting inclusion, median age was 69 (interquartile range 60–81) years, and most occlusions were in the M1 segment (73/107; 68.2%). T7 rate of success was 95.3% (102/107), and there was no association between TI and T7 technical success ( P = 0.23). Greater TIs and cavernous ICA tortuosity grades were not correlated with worse intraprocedural outcomes ( P >0.24). Conclusion In our multicenter experience, T7 performed well even in highly tortuous extracranial vasculature. Successful aspiration catheter delivery and intraprocedural performance were consistent irrespective of ICA tortuosity. Our findings support the use of T7 in aspiration endovascular thrombectomy for acute stroke for patients with tortuous extracranial vasculature.
Activation of the mitogen-activated protein kinase (MAPK) cascade recently was discovered to play an important role in synaptic plasticity in area CA1 of rat hippocampus. However, the upstream ...mechanisms regulating MAPK activity and the downstream effectors of MAPK in the hippocampus are uncharacterized. In the present studies we observed that hippocampal MAPK activation is regulated by both the PKA and PKC systems; moreover, we found that a wide variety of neuromodulatory neurotransmitter receptors (metabotropic glutamate receptors, muscarinic acetylcholine receptors, dopamine receptors, and beta-adrenergic receptors) couple to MAPK activation via these two cascades. In additional studies we observed that PKC is a powerful regulator of CREB phosphorylation in area CA1. MAPK plays a critical role in transcriptional regulation by PKC, because MAPK activation is a necessary component for increased CREB phosphorylation in response to the activation of this kinase. Surprisingly, we also observed that MAPK activation is necessary for PKA coupling to CREB phosphorylation in area CA1. Overall, these studies indicate an unexpected richness of diversity in the regulation of MAPK in the hippocampus and suggest the possibility of a broad role for the MAPK cascade in regulating gene expression in long-term forms of hippocampal synaptic plasticity.
Purpose
Previous comparative mechanical thrombectomy device trials reported a substantial crossover rate from first-line aspiration to stent-retriever thrombectomy. A specialized delivery catheter ...may help track large-bore aspiration catheters to target occlusions. We report our multicenter experience of aspiration thrombectomy of intracranial large vessel occlusions using the FreeClimbTM 70 and Tenzing® 7 delivery catheter (Route 92, San Mateo, CA).
Methods
After local Institutional Review Board approval, we retrospectively reviewed the clinical, procedural, and imaging data of patients who underwent mechanical thrombectomy with the FreeClimb 70 and Tenzing 7.
Results
FreeClimb 70 was successfully delivered using Tenzing 7 to target occlusion in 30/30 (100%) patients (18 M1, 6 M2, 4 ICA-terminus, and 2 basilar artery occlusions), without the use of a stent-retriever for anchoring. In 21/30 (70%) cases, a leading microwire was not needed to advance the Tenzing 7 to the target. Median (interquartile range) time from groin puncture to first pass was 12 (interquartile range 8–15) minutes. Overall first pass effect, or first pass effect (modified thrombolysis in cerebral ischemia 2C-3), was achieved 16/30 (53%). For M1 occlusions, first pass effect was 11/18 (61%). Successful reperfusion (modified thrombolysis in cerebral ischemia ≥ 2B) was achieved in 29/30 (97%) cases after a median of 1 pass (interquartile range 1–3). Median groin puncture to reperfusion time was 16 (interquartile range 12–26) minutes. There were no procedural complications or symptomatic intracranial hemorrhage. Average improvement in National Institutes of Health Stroke Scale at discharge was 6.6 ± 7.1. There were three patient deaths (renal failure, respiratory failure, and comfort care).
Conclusions
Initial data support the use of Tenzing 7 with FreeClimb 70 catheter for reliable access to rapid, effective, and safe aspiration thrombectomy of large vessel occlusions.