Stenting for intracranial stenosis: potential future for the prevention of disabling or fatal stroke

Roles of Nontraditional Lipid Parameters for Predicting Restenosis in Patients with Intracranial Atherosclerotic Stenosis After Endovascular Treatment

PURPOSE

Nontraditional lipid parameters are associated with intracranial atherosclerotic stenosis (ICAS) progression. This study aimed to investigate the association of nontraditional lipid parameters with the risk of restenosis in patients with ICAS after endovascular treatment (EVT).

METHODS

This study retrospectively enrolled consecutive patients with symptomatic ICAS after successful EVT followed by at least 3 months of angiography. Participants were divided into restenosis or non-restenosis groups based on the angiographic follow-up results. The nontraditional lipid parameters were calculated from conventional lipid parameters. The COX regression models and restricted cubic splines (RCS) were used to explore the association between nontraditional lipid parameters and restenosis.

RESULTS

This study recruited 222 cases with 224 lesions eligible for our study, of which 56 (25%) had restenosis. Compared with the non-restenosis group, patients in the restenosis group had higher levels of the atherogenic index of plasma (AIP) (0.211, interquartile range, IQR, 0.065-0.404 vs. 0.083, IQR, -0.052-0.265, P = 0.001), remnant cholesterol (RC) (0.55, IQR, 0.33-0.77 vs. 0.30, IQR, 0.18-0.49, P < 0.001) and Castelli's index‑I (CRI-I) (4.13, IQR, 3.39-5.34 vs. 3.74, IQR, 2.94-4.81, P = 0.030). In the multivariable COX regression analysis, a 0.1 unit increase of AIP was an independent risk factor for restenosis (hazard ratio, HR = 1.20, 95% confidence interval, CI 1.05-1.35, P = 0.005) whereas such an association was not observed for RC (HR = 1.01, 95% CI 0.90-1.15, P = 0.835). The restricted cubic spline (RCS) plot revealed a linear relationship between AIP and restenosis (P for nonlinear = 0.835) but a nonlinear relationship for RC (P for nonlinear = 0.012). Patients were stratified according to tertiles (T) of AIP and RC and the risk of restenosis increased in T3 compared to T1 (HR = 3.21, 95% CI 1.35-7.62, P = 0.008 and HR = 2.99, 95% CI 1.11-8.03, P = 0.030, respectively). Furthermore, this association remained stable within each LDL‑C level subgroup.

CONCLUSION

The AIP and RC were positively and independently associated with restenosis in patients with ICAS after EVT.

Comparing the Impact of Stenting vs. Medical Therapy for Intracranial Arterial Stenosis : A Systematic Review and One-stage and Two-stage Meta-Analysis of Randomized Clinical Trials

PURPOSE

In the treatment of intracranial arterial stenosis (ICAS), controversies remain regarding the optimal treatment strategy. Our study aims to conduct an individual patient-level data meta-analysis of existing RCTs comparing PTAS versus best medical therapy and to identify differences in outcomes such as incidence of ischemic stroke or death.

METHODS

Randomised controlled trials comparing the outcomes of stenting versus best medical therapy for patients who had symptomatic ICAS of >50%. Excluded studies included case reports, case series, reviews, observational studies,  letters or studies evaluating isolated angioplasty techniques without stenting. Data was extracted in accordance with PRISMA guidelines.

RESULTS

7 studies involving 1425 participants were included. There was an increased risk in the incidence of stroke and death within the first 30 days post-procedure for patients treated with PTAS over best medical therapy (RR = 2.22 [1.28-3.86], I² = 0%). Patients who underwent stenting also had a significantly higher risk of intracranial haemorrhage (RR = 12.66 [2.41-66.45], I² = 0%) and death (RR = 5.41 [1.20-24.28], I² = 0%).Under the shared frailty model, stenting when compared to medical therapy has a HR of 1.81 (95% CI:1.25-2.6) of stroke or death across 1 year. Under the parametric Royston-Parmar model, stenting has a significant decrease in the RMST(-0.83 months; 95% CI: -1.30-0.37). Stenting continued to show worse outcomes up to the 3 year mark with a HR of 1.60 (95% CI: 1.11-2.32).

CONCLUSIONS AND RELEVANCE

There is an increased risk of peri- and post-procedural stroke and death over best medical therapy in patients with symptomatic ICAS who undergo PTAS. Further work is required to refine patient selection and mitigate peri-procedural risks.

Transcranial Doppler cerebrovascular reactivity: Thresholds for clinical significance in cerebrovascular disease

BACKGROUND AND PURPOSE

Thresholds for abnormal transcranial Doppler cerebrovascular reactivity (CVR) studies are poorly understood, especially for patients with cerebrovascular disease. Using a real-world cohort with cerebral arterial stenosis, we sought to describe a clinically significant threshold for carbon dioxide reactivity (CO2R) and vasomotor range (VMR).

METHODS

CVR studies were performed during conditions of breathing room air normally, breathing 8% carbon dioxide air mixture, and hyperventilation. The mean and standard deviation (SD) of CO2R and VMR were calculated for the unaffected side in patients with unilateral stenosis; a deviation of 2 SDs below the mean was chosen as the threshold for abnormal. Receiver operating characteristic (ROC) curves for both sides for patients with unilateral and bilateral stenosis were evaluated for sensitivity (Sn) and specificity (Sp).

RESULTS

A total of 133 consecutive CVR studies were performed on 62 patients with stenosis with mean±SD age 55±16 years. Comorbidities included hypertension (60%), diabetes (15%), stroke (40%), and smoking (35%). In patients with unilateral stenosis, mean±SD CO2R for the unaffected side was 1.86±0.53%, defining abnormal CO2R as <0.80%. Mean±SD CO2R for the affected side was 1.27±0.90%. The CO2R threshold predicted abnormal acetazolamide single-photon emission computed tomography (SPECT) (Sn = .73, Sp = .79), CT/MRI perfusion abnormality (Sn = .42, Sp = .77), infarction on MRI (Sn = .45, Sp = .76), and pressure-dependent exam (Sn = .50, Sp = .76). For the unaffected side, mean±SD VMR was 39.5±15.8%, defining abnormal VMR as <7.9%. For the affected side, mean±SD VMR was 26.5±17.8%. The VMR threshold predicted abnormal acetazolamide SPECT (Sn = .46, Sp = .94), infarction on MRI (Sn = .27, Sp = .94), and pressure-dependent exam (Sn = .31, Sp = .90).

CONCLUSIONS

In patients with multiple vascular risk factors, a reasonable threshold for clinically significant abnormal CO2R is <0.80% and VMR is <7.9%. Noninvasive CVR may aid in diagnosing and risk stratifying patients with stenosis.

Intracranial atherosclerosis update for neurointerventionalists

The management of intracranial atherosclerotic disease (ICAD) has been evolving with advanced imaging, refinements of best medical treatment, and the development of endovascular options. There has been a significant increase in the use of endovascular therapy for symptomatic ICAD in the USA over the past 6 years. The rationale for this review is to update neurointerventionalists in these areas so that evidence-based decisions can be considered when counseling potential patients regarding their risks, benefits, and potential complications. The landmark SAMMPRIS trial demonstrated superiority of aggressive medical management (AMM) over intracranial stenting as an initial treatment. However, the risk of disabling or fatal stroke remains high in patients presenting with stroke treated with AMM. Recent studies showed a significantly lower rate of periprocedural complications from intracranial stenting. Patients who have failed medical treatment may therefore benefit from intracranial stenting, particularly in those with hemodynamic compromise and large vessel embolic stroke. Drug coated angioplasty balloons and drug eluting stents may potentially reduce the risk of in-stent re-stenosis. Large vessel occlusion (LVO) due to underlying ICAD is seen in a subset of thrombectomy-eligible patients. The use of stenting as a rescue therapy in LVO thrombectomy has also shown promising early results.

Topology observing 3D device reconstruction from continuous-sweep limited angle fluoroscopy

BACKGROUND

Minimally invasive procedures usually require navigating a microcatheter and guidewire through endoluminal structures such as blood vessels and airways to sites of the disease. For numerous clinical applications, two-dimensional (2D) fluoroscopy is the primary modality used for real-time image guidance during navigation. However, 2D imaging can pose challenges for navigation in complex structures. Real-time 3D visualization of devices within the anatomic context could provide considerable benefits for these procedures. Continuous-sweep limited angle (CLA) fluoroscopy has recently been proposed to provide a compromise between conventional rotational 3D acquisitions and real-time fluoroscopy.

PURPOSE

The purpose of this work was to develop and evaluate a noniterative 3D device reconstruction approach for CLA fluoroscopy acquisitions, which takes into account endoluminal topology to avoid impossible paths between disconnected branches.

METHODS

The algorithm relies on a static 3D roadmap (RM) of vessels or airways, which may be generated from conventional cone beam CT (CBCT) acquisitions prior to navigation. The RM is converted to a graph representation describing its topology. During catheter navigation, the device is segmented from the live 2D projection images using a deep learning approach from which the centerlines are extracted. Rays from the focal spot to detector pixels representing 2D device points are identified and intersections with the RM are computed. Based on the RM graph, a subset of line segments is selected as candidates to exclude device paths through disconnected branches of the RM. Depth localization for each point along the device is then performed by finding the point closest to the previous 3D reconstruction along the candidate segments. This process is repeated as the projection angle changes for each CLA image frame. The approach was evaluated in a phantom study in which a catheter and guidewire were navigated along five pathways within a complex vessel phantom. The result was compared to static cCBCT acquisitions of the device in the final position.

RESULTS

The average root mean squared 3D distance between CLA reconstruction and reference centerline was1.87 ± 0.30 $1.87 \pm 0.30$ mm. The Euclidean distance at the device tip was2.92 ± 2.35 $2.92 \pm 2.35$ mm. The correct pathway was identified during reconstruction in100 % $100\%$ of frames (n = 1475 $n=1475$ ). The percentage of 3D device points reconstructed inside the 3D roadmap was91.83 ± 2.52 % $91.83 \pm 2.52\%$ with an average distance of0.62 ± 0.30 $0.62 \pm 0.30$ mm between the device points outside the roadmap and the nearest point within the roadmap.

CONCLUSIONS

This study demonstrates the feasibility of reconstructing curvilinear devices such as catheters and guidewires during endoluminal procedures including intravascular and transbronchial interventions using a noniterative reconstruction approach for CLA fluoroscopy. This approach could improve device navigation in cases where the structure of vessels or airways is complex and includes overlapping branches.

First-in-human experience of sirolimus coated balloon for symptomatic intracranial artery stenosis

BACKGROUND

The drug coated balloon is a promising endovascular therapy for intracranial atherosclerosis (ICAS), potentially combining the advantages of primary angioplasty and antiproliferative drugs. Previous studies have focused on the paclitaxel coated balloon, revealing promising outcomes in the treatment of ICAS, while concerns about the neurotoxicity of paclitaxel were reported. Sirolimus was shown to have less neurotoxicity in the canine cerebral vasculature. The feasibility and safety of a sirolimus coated balloon (SCB) for ICAS have never been evaluated in humans. We assessed the first-in-human feasibility and safety of SCBs for treating symptomatic patients with severe ICAS.

METHODS

This prospective, open label, single arm cohort study was designed to enroll patients with transient ischemic attacks or non-disabling, non-perforator territory ischemic stroke caused by severe ICAS (70-99%) and following at least 3 weeks after the onset of ischemic symptoms. The primary outcome was stroke or death within 30 days. All patients were followed up to detect restenosis at 6 months.

RESULTS

A total of 60 eligible patients were enrolled with an average age of 59.4±10.8 years. The technical success rate of SCBs for ICAS was 100%. Seven patients (11.7%) required stenting because of flow limited dissections or elastic retraction. Three patients (5.0%) had 30 day strokes, including two ischemic strokes and one hemorrhagic stroke. An additional three patients had recurrent stroke or death during follow-up. Ten patients had restenosis but only two had symptoms.

CONCLUSIONS

SCBs may be feasible and safe in selected patients with symptomatic ICAS, with high grade stenosis (70-99%). Further studies are warranted.

Thirty-Day Outcomes of Resolute Onyx Stent for Symptomatic Intracranial Stenosis: A Multicenter Propensity Score-Matched Comparison With Stenting Versus Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis Trial

BACKGROUND

Symptomatic intracranial atherosclerotic disease (sICAD) is estimated to cause 10% of strokes annually in the United States. However, treatment remains a challenge with several different stenting options studied in the past with unfavorable results.

OBJECTIVE

To report the 30-day stroke and/or death rate associated with intracranial stent placement for sICAD using Resolute Onyx Zotarolimus-Eluting Stent (RO-ZES) and provide a comparison with the results of Stenting Versus Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis (SAMMPRIS) trial.

METHODS

Prospectively maintained databases across 8 stroke centers were used to identify adult patients treated with RO-ZES for sICAD between January 2019 and December 2021. Primary end point was composite of 30-day stroke, intracerebral hemorrhage, and/or death. Propensity score matching was performed using age, hypertension, lipid disorder, cigarette smoking, and symptomatic target vessel to create a matched group for comparison between RO-ZES and the SAMMPRIS medical management and treatment groups (SAMMPRIS percutaneous angioplasty and stenting [S-PTAS]).

RESULTS

A total of 132 patients met the inclusion criteria for analysis (mean age: 64.2 years). Mean severity of stenosis was 81.4% (±11.4%). A total of 4 (3.03%) stroke and/or deaths were reported within 30 days of treatment in the RO-ZES group compared with 6.6% in the SAMMPRIS medical management group (OR [odds ratio] 2.26, 95% CI 0.7-9.56, P = .22) and 15.6% in the S-PTAS group (OR 5.9, 95% CI 2.04-23.4, P < .001). Propensity score match analysis of 115 patients in each group demonstrated 30-day stroke and/or death rate of 2.6% in the RO-ZES group and 15.6% in the S-PTAS group (OR 6.88, 95% CI 1.92-37.54, P < .001).

CONCLUSION

Patients treated with RO-ZES had a relatively low 30-day stroke and/or death rate compared with the S-PTAS group. Further large-scale prospective studies are warranted to evaluate the safety and efficacy of RO-ZES for the treatment of sICAD.

Japanese Postmarket Surveillance of Percutaneous Transluminal Angioplasty and Wingspan Stenting for Intracranial Atherosclerotic Disease

BACKGROUND

The Wingspan stent system was approved as a rescue device for angioplasty of intracranial atherosclerotic disease (ICAD) in 2012. We conducted the government-recommended Japanese Postmarket Surveillance of Percutaneous Transluminal Angioplasty and Wingspan Stenting for Intracranial Atherosclerotic Disease to monitor Wingspan safety and performance.

METHODS

In this open-label, single-arm study at 76 centers in Japan, ICAD subjects were treated with the Wingspan stent between 2014 and 2016. Efficacy end points were successful stent deployment and technical success, defined as stenosis improvement to <50%. Safety end points were ischemic stroke, modified Rankin Scale and National Institutes of Health Stroke Scale scores, adverse events, and mortality. Subjects were considered treated outside of current recommendations if not already receiving antithrombotics or if percutaneous transluminal angioplasty and stenting occurred within 7 days of onset.

RESULTS

The safety cohort included 305 subjects (mean age: 68.7 + 9.6; 83.3% male). Four subjects were removed due to being out of contract. Therefore, 301 subjects were included (mean age: 68.7 ± 9.7; 84.1% male). Successful stent placement was 96.7%. Technical success was observed in 86.8% of lesions. At 1 year, the rate of restenosis was 15.7%, ischemic stroke was 3.9%, and any stroke was 7.9%. Functionally independent outcome (modified Rankin Scale: 0-2) was 88.9% and mortality 3.0%. Significantly more serious adverse events occurred in subjects treated outside of current recommendations (17.9%) versus subjects treated per current recommendations (8.8%) (P = 0.045).

CONCLUSIONS

Endovascular treatment using the Wingspan stent for ICAD is safe and effective in the Japanese population.

Medical and Endovascular Treatments for Intracranial Atherosclerotic Stenosis: A Network Meta-Analysis

Medical treatment and endovascular therapy are widely used for intracranial atherosclerotic stenosis, but the best treatment strategy remains uncertain. The goal of this study was to compare the safety and effectiveness of medical treatment, stenting, and primary balloon angioplasty (PBA). We searched PubMed, MEDLINE, and EMBASE for trials comparing these three treatments for intracranial stenosis up to December 24, 2020. We performed a network meta-analysis with random-effects models. The primary outcome was any stroke or death during a long-term follow-up. Secondary outcomes included ischemic stroke, intracranial hemorrhage, and death. This network meta-analysis included 14 trials with 1520 participants. No significant difference was found between the three groups in the primary outcome, while PBA was probably the best treatment according to the ranking plot. Medical treatment had significantly lower rate of any stroke or death (odds ratio (OR), 0.31; 95% CI, 0.17-0.56), ischemic stroke (OR, 0.43; 95% CI, 0.23-0.81), and intracranial hemorrhage (OR, 0.12; 95% CI, 0.02-0.71) within 30 days than stenting but did not differ from PBA. The ranking plot demonstrated that PBA was also most likely to rank the highest for ischemic stroke during the long-term follow-up and beyond 30 days, although no significant difference was identified. Medical treatment had lower risk of any stroke or death within 30 days than stenting but did not differ from PBA. All the treatments had similar effects on the prevention of long-term stroke, while PBA had the highest probability of being the most effective.

Association between lipid profile changes and risk of in-stent restenosis in ischemic stroke patients with intracranial stenosis: A retrospective cohort study

OBJECTIVE

The risk of ischemic stroke with intracranial stenosis is associated with various serum lipid levels. However, the effects of changes in the lipid profile on the risk of in-stent restenosis have not been verified. Therefore, we investigated the association between the occurrence of in-stent restenosis at 12-month follow-up and changes in various lipid profiles.

METHODS

In this retrospective cohort study, we included ischemic stroke patients who had undergone intracranial stenting for symptomatic intracranial stenosis between February 2010 and May 2020. We collected data about serum low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC), and triglyceride (TG) levels, and calculated the TC/HDL-C and LDL-C/HDL-C ratios at baseline and after 12 months. We conducted multivariable logistic regression analyses to verify the association between various lipid profile changes and in-stent restenosis at 12 months.

RESULTS

Among the 100 patients included in the study (mean age, 60.8 ± 10.0 years; male: 80 [80.0%]), in-stent restenosis was found in 13 (13.0%) patients. The risk of in-stent restenosis of more than 50% was significantly decreased when TC/HDL-C ratio (odds ratio [OR] 0.22, [95% confidence interval (CI) 0.05-0.87]) and LDL-C/HDL-C ratio (OR 0.23, [95% CI 0.06-0.93]) decreased or when HDL-C levels (OR 0.10, [95% CI 0.02-0.63]) were increased at 12 months compared with baseline measurements.

CONCLUSIONS

Improvement of HDL-C levels, TC/HDL-C ratio, and LDL-C/HDL-C ratio were associated with decreased risk of in-stent restenosis at 12-month follow-up. Management and careful monitoring of various lipid profiles including HDL-C levels, TC/HDL-C ratio, and LDL-C/HDL-C ratio may be important to prevent in-stent restenosis in patients with intracranial stenting.

Significant improvement of procedural safety in stenting for basilar stenosis: A historically controlled study

The basilar artery has the most perioperative complications in stenting compared to the other intracranial arteries. We aim to study whether the procedural safety in stenting for basilar stenosis has improved. This study was a single-arm, non-randomized trial that included historically controlled patients for comparison. Between January 2012 and March 2019, 147 consecutive patients with symptomatic basilar stenoses receiving elective stenting treatment were included in current basilar artery stenting (BAS) group. The prospectively collected and registered 120 patients by the same interventional team from September 2001 to November 2011 were set as historical BAS group for control. A total of 267 individuals were included in this study, with a mean age of 59.5 ± 8.1 years. The proportion of patients with lesion length >15 mm was 26.5% (39/147) in the current BAS group versus 4.2% (5/120) in the historical BAS group. We found significant differences between these 2 groups in Mori A (17.7% vs 42.5%) and Mori C patients (42.9% vs 13.3%). The proportion of patients receiving preoperative high-resolution magnetic resonance (HRMRI) evaluation was 83.0% (122/147) in the current BAS group versus 20.8% (25/120) in the historical group (P < .05). Balloon-expendable stent (BES) (n = 1), Wingspan (n = 34), and Enterprise (n = 112) stents were placed in the current BAS group. In contrast, only balloon-expendable stent (BES) (n = 48) and Wingspan (n = 72) were deployed in the historical BAS group. The incidence of the safety endpoint (SE) was 4.1% (involving 6 patients) in the current BAS group versus 11.7% (involving 14 patients) in the historical BAS group (P < .05). In multivariate analysis, no risk factor was associated with the occurrence of the safety endpoint (SE). When BAS cases operated by the surgical team accumulated to 120 to 150, the incidence of complications decreased significantly. This is the largest sample size study to discuss the safety of BAS. The significantly decreased incidence of complications indicates that the improving technical measures and the accumulation of operation experience are necessary.

Spotlight on clinical strategies of Chronic Internal Carotid Artery Occlusion: Endovascular interventions and external-intracarotid bypasses compared to conservative treatment

Chronic internal carotid artery occlusion (CICAO) has high prevalence and incidence rates, and patients with CICAO can be completely asymptomatic, experience a devastating stroke or die. It is important to note that CICAO causes cerebrovascular accidents. Currently, the external carotid-internal carotid (EC-IC) bypass technique is used to treat CICAO. However, many clinical studies showed that EC-IC bypass was not beneficial for many patients with CICAO. Meanwhile, endovascular intervention treatment options for CICAO are evolving, and an increasing number of patients are undergoing endovascular intervention therapy. Accordingly, a review comparing both techniques is warranted. For this review, we searched PubMed and collected relevant case study reports comparing endovascular interventional therapy and internal and external cervical bypass surgeries to provide strategies for clinical treatment.

Long-term clinical and angiographic outcome from angioplasty and stenting for intracranial stenosis

BACKGROUND

Severe intracranial atherosclerotic stenosis (ICAS) is a major cause of stroke. Although percutaneous transluminal angioplasty and stenting (PTAS) treatment methods have increased over the last decade as alternative therapies, there is debate regarding the best method of treatment, with medical and surgical therapies often suggested.

METHODS

We analyzed the long-term follow-up results from 5 years of intracranial stenting for intracranial stenosis from three stroke centers. The primary endpoints were early stroke complications or death within 30 days after stent insertion, and the secondary endpoint was a recurrent stroke between 30 days and 60 months. Correlating factors and Kaplan-Meier survival curves for recurrent stroke and in-stent restenosis (ISR) were also obtained.

RESULTS

Seventy-three PTAS in 71 patients were examined in this study. The primary and secondary endpoints were all 8.2% (n = 6), and restenosis was 13.7% (n = 10) during the 5-year follow-up. The primary endpoints were significantly frequent in the high National Institutes of Health Stroke Scale (NIHSS) and early stent (≤ 7 days after dual antiplatelet medication) groups. Secondary endpoint and ISR were identically frequent in the younger age group and in the presence of tandem stenosis in other major intracranial arteries. The cumulative probability of recurrent stroke and ISR at 60 months was 16.4% and 14.1%, respectively.

CONCLUSIONS

This study shows that PTAS is safe and effective for major ICAS. Reducing the early complication rate is still an important factor, despite the fact that long-term stroke recurrence was low.

Application of drug-coated balloons for intracranial atherosclerosis disease: a systematic review

BACKGROUND

Although percutaneous transluminal angioplasty and stenting (PTAS) was an effective and safe alternative treatment for severe intracranial atherosclerosis disease (ICAD), the high rate of restenosis remained a major issue for this endovascular procedure. Recently, the application of drug-coated balloons (DCB) in ICAD was developed to reduce restenosis. This systematic review aimed to evaluate the efficacy and safety of DCB angioplasty for ICAD.

METHODS

We searched relevant databases for eligible studies enrolling ICAD patients treated with DCB. The event rates of restenosis and periprocedural complications in the follow-up period were pooled with random-/fixed-effect models using Freeman-Tukey double arcsine transformation. Heterogeneity tests and publication bias tests were performed.

RESULTS

Two hundred and twenty-four ICAD patients treated with DCB from 9 eligible studies were included. Rate of stenosis in the DCB arm before treatment was ranged from 62% to 90% and reported median follow-up was ranged from 3 to 10.7 months. The pooled incidence of restenosis were 5.7% (95% confidence interval [CI] 2.6%-9.7%; I² = 0%, p = 0.516) and 5.9% for periprocedural complications (95% CI: 2.5-10.3%; I² = 0%, p = 0.649) in follow-up term.

CONCLUSION

With the limitation of the low quality of the available evidence, angioplasty with DCB appears to be effective and safe in severe ICAD. Further larger randomized trials are needed to provide more definitive evidence and to address the ideal clinical context for their application.

Intracranial atherosclerotic disease and acute ischaemic stroke: A review of diagnosis and management

Intracranial atherosclerotic disease is highly prevalent and a common cause of ischaemic stroke globally. With the increasing use of endovascular treatment for acute stroke management, computed tomography and magnetic resonance imaging have become an essential part of patient selection. In this review, we present the typical imaging findings of intracranial atherosclerosis and an overview of management as relevant to diagnostic and interventional radiologists.

Use of quantitative magnetic resonance angiography in patients with symptomatic intracranial arterial stenosis who undergo stenting: Presentation of three cases

Intracranial atherosclerotic disease (ICAD) is an important cause of ischemic stroke. The etiology of stroke in patients with ICAD could be due to several mechanisms including hypoperfusion, artery-to-artery embolism, and plaque extension over small penetrating artery ostia. Management of symptomatic ICAD includes medical and endovascular management. Quantitative magnetic resonance angiography (MRA) is a technique that allows for non-invasive measurement of large vessel blood flow in the head and neck. Here, we describe procedural and clinical outcomes on three patients who presented with symptomatic ICAD and were treated with angioplasty and stenting. Quantitative MRA was used pre- and post- procedurally to assess the effects of stenting on the intracranial blood flow. Quantitative measures of intracranial blood flow may serve as an additional triage tool in the evaluation of patients with symptomatic ICAD.

Balloon-mounted stenting for ICAS in a multicenter registry study in China: a comparison with the WEAVE/WOVEN trial

Background

The outcome of deploying balloon-mounted stents for symptomatic intracranial atherosclerotic stenosis (ICAS) has not been fully investigated. In this study we evaluate the safety and long-term outcome of using balloon-mounted stents to treat symptomatic ICAS in comparison with the WEAVE/WOVEN study.

Methods

In a multicenter registry study of stenting for symptomatic intracranial artery stenosis in China, 159 patients treated with an intracranial balloon-mounted stent approved by the China Food and Drug Administration were evaluated. The morphological features of the lesions were categorized by Mori classification. The endpoints, including periprocedural and long-term clinical and radiological outcomes, were the same as those in the WEAVE/WOVEN study.

Results

In the present study the mean percent stenosis before and after stenting was 84.0% and 6.1%, respectively. The proportions of Mori A, Mori B, and Mori C lesions were 33.3%, 52.2%, and 14.5%, respectively. The 72-hour rates of stroke and mortality after the procedure were 0%. The 1-year rates of any stroke, ischemic stroke, hemorrhagic stroke, and death were 6.3% (10/159), 5.7% (9/159), 0.6% (1/159), and 0.6% (1/159), respectively. The 1-year rate of in-stent restenosis (ISR) was 23.4% (15/64). The rate of ISR in Mori C lesions (53.8%, 7/13) was significantly higher than that in Mori A (15.8%, 3/19) or Mori B lesions (15.6%, 5/32) (p=0.024).

Conclusions

The short-term and long-term outcomes of using a balloon-mounted stent for symptomatic ICAS with focal and non-angular lesions (Mori A and B type) and smooth arterial access were comparable to the results of the WEAVE/WOVEN trial.

Medium- and long-term effects of endovascular treatments for severely stenotic basilar arteries supported by multimodal imaging

BACKGROUND

To evaluate the medium-and long-term effect of intravascular interventional therapy for symptomatic severe basilar artery stenosis supported by multimodal imaging.

METHOD

After strict screening of 67 patients with symptomatic severe basilar artery stenosis (70-99%) with atherosclerotic stenosis, 67 patients with symptomatic recurrence after intensive drug treatment were treated with intravascular balloon dilatation and Enterprise stent implantation. Any stroke or death within 30 days after operation and any stroke and restenosis during medium-and long-term follow-up were recorded.

RESULTS

①The mean age of 67 patients (67lesions) was 57 ± 8 years old, and the technical success rate was 100%; ②Preoperative angiography showed that the collateral circulation was poor, and TICI was 1-2a while postoperative angiography showed that TICI was significantly improved to 2b-3; ③The average preoperative stenosis rate was 82 ± 9%, and the postoperative stenosis rate was reduced to 17 ± 10%; ④Before surgery, abnormal perfusion was found in the posterior circulation CTP; After the postoperative re-examination, the posterior circulation of CTP perfusion was significantly improved; ⑤Postoperative symptoms and neurological conditions improved significantly; ⑥Complications of perforating branch event occurred in 1 case after operation, and symptoms were relieved after more than 1 month of medication treatment, and mild neurological dysfunction remained. 1 case developed subacute thrombosis in the stent, which improved after active intra-arterial thrombolysis, and there was no residual neurological dysfunction; and 1 case of micro-guide wire being trapped by the distal vasospasm. ⑦67 patients were followed up by telephone, WeChat or imaging for 36-66 months.

CONCLUSIONS

In summary intravascular balloon dilation + Enterprise stent implantation is safe and effective for the treatment of symptomatic severe atherosclerotic stenosis of the basilar artery, with high technical success rate, low perioperative complications, and good mid-term and long-term effects.

Interventional Neuroradiology: A Review

Interventional neuroradiology (INR) has evolved from a hybrid mixture of daring radiologists and iconoclastic neurosurgeons into a multidisciplinary specialty, which has become indispensable for cerebrovascular and neurological centers worldwide. This manuscript traces the origins of INR and describes its evolution to the present day. The focus will be on cerebrovascular disorders including aneurysms, stroke, brain arteriovenous malformations, dural arteriovenous fistulae, and atherosclerotic disease, both intra- and extracranial. Also discussed are cerebral vasospasm, venolymphatic malformations of the head and neck, tumor embolization, idiopathic intracranial hypertension, inferior petrosal venous sinus sampling for Cushing's disease, and spinal interventions. Pediatric INR has not been included and deserves a separate, dedicated review.

The WOVEN trial: Wingspan One-year Vascular Events and Neurologic Outcomes

BACKGROUND

Prior studies evaluating the Wingspan stent for treatment of symptomatic intracranial atherosclerotic disease have included patients with a spectrum of both on-label and off-label indications for the stent. The WEAVE trial assessed 152 patients stented with the Wingspan stent strictly by its current on-label indication and found a 2.6% periprocedural stroke and death rate.

OBJECTIVE

This WOVEN study assesses the 1-year follow-up from this cohort.

METHODS

Twelve of the original 24 sites enrolling patients in the WEAVE trial performed follow-up chart review and imaging analysis up to 1 year after stenting. Assessment of delayed stroke and death was made in 129 patients, as well as vascular imaging follow-up to assess for in-stent re-stenosis.

RESULTS

In the 1-year follow-up period, seven patients had a stroke (six minor, one major). Subsequent to the periprocedural period, no deaths were recorded in the cohort. Including the four patients who had periprocedural events in the WEAVE study, there were 11 strokes or deaths of the 129 patients (8.5%) at the 1-year follow-up.

CONCLUSIONS

The WOVEN study provides the 1-year follow-up on a cohort of 129 patients who were stented according to the current on-label use. It provides a more homogeneous patient group for analysis than prior studies, and demonstrates a relatively low 8.5% 1-year stroke and death rate in stented patients.

Intracranial Atherosclerosis: A Disease of Functional, not Anatomic Stenosis? How Trans-Stenotic Pressure Gradients Can Help Guide Treatment

BACKGROUND

Most trials have assessed intracranial atherosclerotic disease (ICAD) severity based on angiographic stenosis. However, anatomic stenosis might not accurately identify the actual state of functional post-stenotic flow limitation.

OBJECTIVE

To investigate whether angiographic stenosis correlates with physiologic distal flow limitation, measured as trans-stenotic pressure gradients, in ICAD patients.

METHODS

In patients referred for endovascular treatment of anterior circulation symptomatic ICAD who failed maximal medical therapy (MMT) per SAMMPRIS (Stenting versus Aggressive Medical Therapy for Intracranial Arterial Stenosis) criteria, angiographic luminal diameters and percentages of stenosis were correlated with trans-stenotic pressure gradients, calculated as distal/proximal pressure ratios (DPPR) and proximal minus distal pressure gradients (PDPG), by way of Spearman correlation coefficients.

RESULTS

Nine patients (3 men, 6 women) were evaluated. Atherosclerotic lesions' locations included internal carotid artery in 5 subjects (2 cavernous, 3 supraclinoid) and proximal middle cerebral artery (M1) in 4 patients. Mean percentage of stenosis was 80 ± 8% (range 75%-94%). Minimal lumen diameter at the most stenotic ICAD site ranged from 0.2 to 0.9 mm (0.59 ± 0.41 mm). DPPR ranged from 0.38 to 0.63 (0.56 ± 0.14). PDPG ranged from 35 to 57 mm Hg (50 ± 8 mm Hg). Spearman coefficients showed no correlation between DPPR or PDPG and angiographic minimal luminal diameters or percentages of stenosis. There were no procedural complications related to trans-stenotic pressure measurements.

CONCLUSION

Angiographic stenosis does not reflect the physiologic severity of distal flow limitation in patients with ICAD. Hemodynamic assessment using trans-stenotic pressure ratios and gradients may serve as a more reliable predictive biomarker for MMT failure and response to revascularization.

WEAVE Trial: Final Results in 152 On-Label Patients

Background and Purpose- The WEAVE trial (Wingspan Stent System Post Market Surveillance) is a postmarket surveillance trial mandated by the Food and Drug Administration to assess the periprocedural safety of the Wingspan Stent system in the treatment of symptomatic intracranial atherosclerotic disease. Methods- A total of 152 consecutive patients who met the Food and Drug Administration on-label usage criteria were enrolled at 24 hospitals and underwent angioplasty and stenting with the Wingspan stent. On-label criteria included age 22 to 80 years, symptomatic intracranial atherosclerotic stenosis of 70% to 99%, baseline modified Rankin Scale score ≤3, ≥2 strokes in the vascular territory of the stenotic lesion with at least 1 stroke while on medical therapy, and stenting of the lesion ≥8 days after the last stroke. The primary analysis assessed the periprocedural stroke, bleed, and death rate within 72 hours of the procedure with adjudication by a core study Stroke Neurologist. Results- The trial was stopped early after interim analysis of 152 consecutive patients demonstrated a lower than expected 2.6% (4/152 patients) periprocedural stroke, bleed, and death rate. This was lower than the 4% periprocedural primary event safety benchmark set for the interim analysis in the study. A total of 97.4% (148/152) patients were event-free at 72 hours, 1.3% (2/152) had nonfatal strokes, and 1.3% (2/152) of patients died. Conclusions- With experienced interventionalists, and proper patient selection following the on-label usage guidelines, the use of the Wingspan stent for intracranial atherosclerotic disease demonstrated a low periprocedural complication rate and excellent safety profile. This is the largest on-label, multicenter, prospective trial of the Wingspan stent system to date with the lowest reported complication rate. Clinical Trial Registration- URL: https://www.clinicaltrials.gov . Unique identifier: NCT02034058.

Update in the treatment of intracranial atherosclerotic disease

This review highlights the recent evolution of the imaging, medical management, surgical options and endovascular therapies for symptomatic intracranial atherosclerotic disease (ICAD). Recent imaging developments including optical coherence tomography and other modalities to assess the intracranial arteries for symptomatic ICAD are reviewed, not only to diagnose ICAD but to determine if ICAD plaques have any high-risk features for treatment. Potential future developments in the treatment of ICAD are discussed, including the development of trackable drug-coated balloons for the cerebral circulation to treat primary or restenotic arteries, new iterations of self-expanding intracranial stents with easier delivery systems, and the re-examination of indirect surgical bypass techniques for revascularisation. In addition to these important technological developments, however, is the evolving evidence regarding the best treatment window for these techniques and additional factors in medical management which can improve patient outcomes in this devastating pathology.

Rescue Intracranial Stenting After Failed Mechanical Thrombectomy for Acute Ischemic Stroke: A Systematic Review and Meta-Analysis

BACKGROUND

Up to 20% of patients fail to achieve reperfusion with modified Thrombolysis in Cerebral Infarction (mTICI) scores of 0-1 after mechanical thrombectomy (MT). Furthermore, underlying intracranial atherosclerotic disease, particularly when associated with >70% residual or flow limiting stenosis, is associated with higher rates of failed MT and high failure risk MT. The aim of this study was to systematically review the procedural and clinical outcomes in patients with failed MT and high failure risk MT. We also explored differences between patients receiving acute rescue stenting compared with medical management alone.

METHODS

A systematic literature search was conducted in Ovid MEDLINE, PubMed, Embase, and Cochrane online scientific publication databases for English language publications from their date of inception until October 2018. Studies including adult patients with acute ischemic stroke because of emergent large vessel occlusion with failed (mTICI score 0-1) or high failure risk MT within the anterior circulation who underwent rescue stenting were included. A systematic review and meta-analysis of proportions was performed.

RESULTS

Rescue intracranial stenting after failed MT or high failure risk MT results in improved clinical outcomes compared with patients without stenting (48.5% vs. 19.7%, respectively; P < 0.001), without an increase in the rate of symptomatic intracranial hemorrhage, despite additional use of antiplatelet agents (9.7% vs. 14.1%, respectively; P = 0.04).

CONCLUSIONS

In patients who fail initial attempts at MT or are high risk for acute reocclusion, rescue intracranial stenting could be considered with the aim to improve functional outcomes. Antiplatelet agents do not increase the risk of hemorrhage in these patients.

[Effect of Naoluo Xintong on proliferation and differentiation of neural stem cells and β-tubulin Ⅲ/GFAP]

OBJECTIVE

To observe the effects of Naoluo Xintong on the expression of β-tubulin Ⅲ and glial fibrillary acidic protein (GFAP) and the proliferation and differentiation of murine neural stem cells (NSCs) in vitro.

METHODS

An immortalized murine NSC line was divided into model control (MC) group, 10% Naoluo Xintong drug-containing serum group (NLXT group), and 10% Naoluoxintong drug-containing serum with inhibitor Y27632 group (Y-27632 group) with corresponding treatments. The activity of the NSCs was detected after the treatments using MTT assay, and the migration of the cells was observed with Transwell assay. The expressions of β-tubulin Ⅲ, GFAP and MAP-2 proteins in the cells were detected with immunoblotting, and the expressions of DCX, NEUN, and β-tubulin Ⅲ were also detected with immunofluorescence assay.

RESULTS

Compared with that in MC group, the number of migrated cells in NLXT group and Y-27632 group increased significantly at 1 day and 3 days after induction (P < 0.05). The survival rate and the number of migrated cells in NLXT group and Y-27632 group increased significantly on day 7 (P < 0.01). Compared with those in MC group, the expressions of β-tubulin Ⅲ, MAP2 and GFAP protein in NLXT group and Y-27632 group were significantly increased on days 3 (P < 0.01) and 7 (P < 0.05). The numbers of β-tubulinⅢ/ GFAP, BrdU/DCX, and BrdU/NEUN labeled cells in the NLXT group and Y-27632 group were significantly greater than those in the MC group.

CONCLUSIONS

Naoluo Xintong promotes the proliferation and differentiation of murine NSCs in vitro by regulating the expressions of β-tubulinⅢ/GFAP.

Thirty-Day Outcomes of the Enterprise Stent in Treating Hypoperfusion of Symptomatic Intracranial Stenosis

OBJECTIVE

To evaluate the 30-day outcomes of using the Enterprise stent to treat patients with hypoperfusion of symptomatic severe intracranial stenosis.

METHODS

Patients with symptomatic severe intracranial stenosis (70%-99%) who underwent Enterprise stent intervention between August 2014 and November 2018 were retrospectively analyzed. The 30-day primary outcomes included the success rate of stenting and the incidence of complications, including ischemic stroke, cerebral hemorrhage, and death. The 30-day complication rates of patients with different lesion locations and classifications of Mori morphology were compared.

RESULTS

Sixty-eight patients were treated using 70 Enterprise stents. The success rate was 100%. The 30-day complication rate was 4.4%. The rates of ischemic stroke, cerebral hemorrhage, and death were 1.5%, 2.9%, and 0%, respectively. No significant difference was found in the 30-day complication rate between patients with different lesion locations and classifications of Mori morphology (P > 0.05).

CONCLUSION

Enterprise stents were relatively safe in treating patients with hypoperfusion of symptomatic severe intracranial stenosis.