Percutaneous transluminal angioplasty for intracranial atherosclerotic lesions: evolution of technique and short-term results

A bibliometric analysis of the 100 most-cited clinical articles in the research of intracranial artery stenosis and intracranial atherosclerosis

Background

Intracranial arterial stenosis (ICAS), caused by intracranial atherosclerosis, is one of the major causes of ischemic stroke. This study identified the top 100 most-cited publications on ICAS through a bibliometric analysis.

Methods

Two independent authors conducted a search in the Web of Science database for clinical articles on ICAS published between 1993 and 2022. The top 100 most-cited articles were then extracted. For each article, the analysis covered the title, author, country of origin/affiliation, journal, total number of citations, number of citations per year, and type of study.

Results

The top 100 most-cited papers in the ICAS were authored by 565 authors from 12 countries and published in 29 journals. In terms of the 5-year trend, the largest number of papers were published between 2003 and 2007 (n = 31). The median number of citations for the 100 papers was 161 (range 109-1,115). The journal with the highest proportion of the 100 most published articles was Stroke, accounting for 41% of articles and 37% of the citations. According to country of origin, the United States of America accounted for the largest number of articles, followed by China, Japan, and South Korea, with these four countries together accounting for 81% of the total number of articles and 88% of the citations. Trends in the past five years included the use of terms such as acute ischemic stroke and mechanical thrombectomy.

Conclusion

The findings of this study provide novel insight into this field and will facilitate future research endeavors.

Experience of using coronary perfusion balloon catheter for acute middle cerebral artery occlusion

Background

We present the case of an individual with acute occlusion of the middle cerebral artery caused by atherosclerosis. The patient underwent angioplasty using a coronary perfusion balloon, which resulted in a favorable clinical outcome.

Case Description

A 66-year-old male patient presented with an acute onset of right hemiplegia and dysarthria. Magnetic resonance imaging revealed an occlusion of the left middle cerebral artery, and alteplase was administered, followed by a mechanical thrombectomy and intracranial balloon catheter angioplasty. Due to restenosis, a coronary perfusion balloon catheter was used for a 15-minute angioplasty procedure while maintaining the perfusion. This treatment approach led to the recanalization of the artery and favorable clinical outcomes.

Conclusion

The coronary perfusion balloon may represent a viable therapeutic alternative for the management of refractory intracranial atherosclerotic large vessel occlusion.

Long-term outcome and factors associated with restenosis after combination therapy of balloon angioplasty and stenting for symptomatic intracranial stenosis

BACKGROUND

The optimal treatment for intracranial artery stenosis (ICAS) has not been established. We retrospectively examined the initial and long-term outcomes associated with restenosis of a combination therapy of balloon angioplasty and stenting for symptomatic atherosclerotic ICAS.

METHODS

Consecutive patients who underwent balloon angioplasty and/or stenting for ≥ 70% ICAS between 2006 and 2020 were analyzed. Patients within 48 h of stroke onset were excluded. The following procedures were established as standards at our institution: (1) primary balloon angioplasty alone was initially performed; (2) stenting for insufficient dilatation, recoiling, or dissection was conducted; and (3) stenting was considered for restenosis. Intracranial ischemic and hemorrhagic complications within 30 days after treatment were used to evaluate periprocedural safety. Recurrent ischemic events, restenosis and restenosis related factors were used to be evaluate the long-term outcome.

RESULTS

A total of 160 patients were recruited. Initial treatment consisted of balloon angioplasty (n = 101) and stenting (n = 59). Intracranial complications within 30 days after treatment were ischemic in five (3.1%) and hemorrhagic in four patients (2.5%). The incidence of these complication was 3.1% in the stenting group and 2.5% in the balloon angioplasty group. The mean follow-up period was 53.9 months. Restenosis was found in 42 patients (26%). Recurrent ischemic events during follow-up were noted in 14 patients (8.8%), of which six patients had TIA and eight patients had ischemic stroke. Restenosis-associated factors included diabetes, coronary artery disease, percent stenosis after treatment, and balloon angioplasty in logistic univariate analysis. Multivariate Cox regression analysis showed that diabetes (HR: 2.084, CI: 1.039-4.180, p = 0.0386), length of lesion (HR; 1.358, CI: 1.174-1.571, p < 0.0001), and balloon angioplasty (HR: 4.194, CI: 1.083-16.239, p = 0.0379) were independent predictors for restenosis.

CONCLUSION

Combination therapy of balloon angioplasty and stenting for symptomatic ICAS had a low perioperative stroke rate and may improve long-term outcome. Balloon angioplasty, diabetes, and length of lesion were significantly associated with restenosis.

Factors Influencing the Outcome of Symptomatic Intracranial Artery Stenosis With Hemodynamic Impairment After Short and Long-Term Stent Placement

Objective

Stent placement is a feasible approach worldwidely for patients with symptomatic intracranial artery stenosis (sICAS) and hemodynamic impairment (HI) who are at high risk of recurrent stroke after medical treatment. Exploration of factors associated with poor outcomes after stent placement could help develop better individualized therapeutic strategies.

Methods

This study conducted a post-hoc analysis of a prospective, multicenter registry study of stent use for sICAS with HI in China. Patient and clinical demographics, and stenotic lesion images were analyzed using univariate and multivariate Cox regression to the time until any endpoints or the end of the follow-up period. The short-term endpoint included any transient ischemic attack (TIA), stroke, or death within 1 month after stent placement. The long-term endpoints included the short-term endpoints and any TIA or stroke in the region of the affected artery that occurred more than 1 month after stent placement.

Results

Two hundred and ninety two patients were included, with 13 short-term and 39 long-term endpoints. Multivariate Cox regression analysis revealed that lesions at the arterial origin or bifurcation (Hazard Ratio (HR) = 7.52; 95% CI, 1.89-29.82; p = 0.004) were significantly associated with higher short-term risk. Baseline renal insufficiency reduced the risk (HR = 0.08; 95% CI: 0.01-0.68; p = 0.021). Factors significantly associated with higher long-term risk included irregular or ulcerated plaques at the lesion (HR = 2.15; 95% CI: 1.07-4.33; p = 0.031). Subgroup analyses indicated that higher risk occurred in the older age group (age>59 years, HR = 3.73, 95% CI: 1.27-10.97, p = 0.017), and not in the younger group (age≤59 years, HR = 1.12, 95% CI: 0.42-3.03, p = 0.822).

Conclusion

Irregular or ulcerated plaques in older patients and lesions at the arterial opening or bifurcation were more likely to result in adverse endpoints for stent placement during long or short -term follow-up. Investigation of these factors might facilitate the development of individualized therapeutic strategies for this population.

Clinical Trial Registration

http://www.clinicaltrials.gov, identifier: NCT01968122.

Endovascular Therapy for Intracranial Giant Cell Arteritis : Systematic Review, Technical Considerations and the Effect of Intra-arterial Calcium Channel Blockers

BACKGROUND

Giant cell arteritis (GCA) is a systemic vasculitis that may cause ischemic stroke. Rarely, GCA can present with aggressive intracranial stenoses, which are refractory to medical therapy. Endovascular treatment (EVT) is a possible rescue strategy to prevent ischemic complications in intracranial GCA but the safety and efficacy of EVT in this setting are not well-described.

METHODS

A systematic literature review was performed to identify case reports and series with individual patient-level data describing EVT for intracranial GCA. The clinical course, therapeutic considerations, and technique of seven endovascular treatments in a single patient from the authors' experience are presented.

RESULTS

The literature review identified 9 reports of 19 treatments, including percutaneous transluminal angioplasty (PTA) with or without stenting, in 14 patients (mean age 69.6 ± 6.3 years). Out of 12 patients 8 (66.7%) with sufficient data had > 1 pre-existing cardiovascular risk factor. All patients had infarction on MRI while on glucocorticoids and 7/14 (50%) progressed despite adjuvant immunosuppressive agents. Treatment was PTA alone in 15/19 (78.9%) cases and PTA + stent in 4/19 (21.1%). Repeat treatments were performed in 4/14 (28.6%) of patients (PTA-only). Non-flow limiting dissection was reported in 2/19 (10.5%) of treatments. The indications, technical details, and results of PTA are discussed in a single illustrative case. We report the novel use of intra-arterial calcium channel blocker infusion (verapamil) as adjuvant to PTA and as monotherapy, resulting in immediate improvement in cerebral blood flow.

CONCLUSION

Endovascular treatment, including PTA with or without stenting or calcium channel blocker infusion, may be effective therapies in medically refractory GCA with intracranial stenosis.

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.

A Comparison of Safety and Effectiveness Between Wingspan and Neuroform Stents in Patients With Middle Cerebral Artery Stenosis

Background: Percutaneous transluminal angioplasty and stenting with the Wingspan stent has proven safe and effective in patients with middle cerebral artery stenosis (MCAS), but the off-label use of the Neuroform stent might be an alternative treatment. This study aimed to compare the safety and effectiveness of the above two intracranial stents in patients with MCAS. Methods: We retrospectively analyzed consecutive patients with symptomatic MCAS who had been treated with the Neuroform EZ or the Wingspan stent. A propensity score was generated to control for differences in baseline characteristics. The endpoints were the rate of peri-procedural complications within 30 days after stenting, the in-stent restenosis rate, and any target-vessel-related stroke or deaths during follow-up. Results: After matching for propensity score, the peri-procedural complication rate in the Wingspan group was 7.4% compared with 5.6% in the Neuroform group (p = 1.00), while the follow-up in-stent restenosis rates were 23.3 vs. 14.3%, respectively (p = 0.41). In the restenosis group, the patients tended to be younger (p < 0.01) and the degree of artery stenosis before stenting was higher (p < 0.01). Conclusion: This study indicated that in patients with symptomatic MCAS, Neuroform EZ stents are an alternative to Wingspan. Moreover, younger age and higher degree of artery stenosis before stenting might be a risk factor of in-stent restenosis.

Outcomes of Balloon Angioplasty and Stenting for Symptomatic Intracranial Atherosclerotic Stenosis at a High Volume Center

PURPOSE

This study investigated the periprocedural complication rates, long-term outcome, and restenosis of endovascular treatment for intracranial atherosclerotic stenosis (ICS) at our hospital.

METHODS

We retrospectively analyzed the clinical data of 217 patients comprising 256 endovascular treatments for high-grade symptomatic ICS. The lesion was located in the internal carotid artery in 77, the middle cerebral artery in 111, the basilar artery in 29, and the vertebral artery in 39. Patients were divided into two groups, before (early-phase group, 1999-2013) and after approval of Wingspan (late-phase group, 2014-2017).

RESULTS

In the early-phase group (n = 163), 157 lesions were treated by balloon angioplasty and 31 (17%) by coronary stenting. In the late-phase group (n = 54), 33 lesions were treated by balloon angioplasty and 35 (52%) by Wingspan stenting. Overall technical success rates were 96% in the balloon angioplasty and 100% in stenting groups. The 30-day rate of stroke, TIA, and death were 4.8% in the early-phase group and 4.4% in the late-phase group. There was one minor stroke and two TIAs during the follow-up period in the late-phase group.

CONCLUSIONS

Endovascular treatment for symptomatic ICS in this study appeared to be safe and effective if patients are properly selected. However, future well-designed randomized trials with different techniques and modified patients selection criteria are certainly warranted.

Leave Nothing Behind: Treatment of Intracranial Atherosclerotic Disease with Drug-Coated Balloon Angioplasty

PURPOSE

Intracranial atherosclerosis disease (ICAD) is an essential cause of stroke. The characteristics of effective treatment include low periprocedural risk and a sustained treatment effect. Angioplasty with a conventional balloon for ICAD is safe but has a dauntingly high restenosis rate. Drug-coated balloon (DCB) angioplasty might reduce the risk of restenosis while maintaining the overall safety of the procedure.

METHODS

This study included symptomatic ICAD patients with more than 70% stenosis. Intermediate catheters were placed distally, and the lesions were predilated with a conventional balloon, followed by a DCB (SeQuent Please, B Braun, Melsungen, Germany). The primary endpoint was any stroke or death within 30 days or ipsilateral ischemic stroke thereafter. The secondary endpoint was arterial restenosis of more than 50% during follow-up.

RESULTS

A total of 39 sessions of DCB angioplasty were performed for 39 lesions in 35 patients between October 2015 and April 2018 in a single center. All of the DCBs could be navigated to the lesions. Major periprocedural complications were noted in two patients (5.7%, 2/35), and minor periprocedural complications were also noted in two patients (5.7%, 2/35). The average percentages of stenosis of the lesions were 76.6% ± 7% before treatment, 32.4% ± 11.2% after DCB angioplasty, and 25% ± 16% at follow-up. Stenosis over 50% was present in 3 lesions during the follow-up period (8.3%, 3/36).

CONCLUSION

In this study, the application of DCBs to treat ICAD patients was feasible and safe. A larger scale clinical trial is warranted to further evaluate the safety and efficacy of this treatment.

Drug-Coated Balloon Treatment in Symptomatic Intracranial High Grade Stenosis : A Retrospective Study of 33 Patients

PURPOSE

Endovascular therapy (EVT) represents an alternative treatment modality for symptomatic intracranial high-grade atherosclerotic stenosis (sICAS); however, periprocedural complication rates as well as midterm restenosis rates represent relevant limitations of EVT. Drug-coated balloon percutaneous transluminal angioplasty (DCB-PTA) may overcome some of these shortcomings. The aim of this study was to assess feasibility and safety as well as the stroke recurrence rate in 33 patients.

METHODS

A retrospective, monocentric cohort study of sICAS patients treated with DCB-PTA. Outcome measures were the periprocedural intracranial complication rate, the recurrent stroke rate and mortality during follow-up.

RESULTS

This cohort study included 33 patients with 35 sICAS treated with DCB-PTA. The median age was 72 years (interquartile range, IQR 66-77 years); median clinical and mean radiological follow-up time was 9 months (IQR 3-22 months). Median preprocedural degree of stenosis (WASID) was 80% (IQR 73-80%) and median postprocedural residual stenosis degree (WASID) was 50% (IQR 33-60%). Intracranial periprocedural complications occurred in 2 (6%) patients. The overall restenosis rate was 15% (n = 5). In four patients a symptomatic ischemic re-event occurred within 7 months after the initial treatment. None of the patients died.

CONCLUSION

This DCB-PTA cohort study showed a relatively low intracranial complication rate of 6% with a symptomatic recurrence rate of 12%. Larger trials are needed to validate these promising observations.

Intracranial Atherosclerotic Stenoses: Pathophysiology, Epidemiology, Risk Factors and Current Therapy Options

Intracranial atherosclerotic stenoses (ICAS) are one of the most common causes of first and recurrent cerebrovascular ischaemic events worldwide, with highest prevalence in Asian, Hispanic and African populations. Clinical trials have improved the understanding of epidemiology, risk factors and imaging characteristics of patients with ICAS. Current therapeutic approaches concerning these patients include management of risk factors, best medical therapy, potentially endovascular and rarely surgical therapy. In our review, we elucidate the current epidemiology and evidence in evaluation of risk factors and therapeutic options for providing favourable outcome for patients with ICAS.

Submaximal angioplasty in the treatment of patients with symptomatic ICAD: a systematic review and meta-analysis

Introduction

Management approaches for intracranial atherosclerosis include medical, surgical, or endovascular treatment. Among endovascular treatments, recent studies have stated that submaximal angioplasty (SA) may offer considerable benefits and be a promising alternative to aggressive medical therapyand/or stenting in the treatment of intracranial atherosclerotic disease (ICAD).

Objective

To investigate the rates of periprocedural and long-term cerebrovascular accidents, mortality, and restenosis in patients with symptomatic ICAD who were treated with SA.

Methods

An electronic database search was performed for relevant studies that reported clinical outcomes of patients with ICAD following SA. Outcomes of interest were incidence of transient ischemic attack, intracerebral hemorrhage, stroke, and mortality in the periprocedural period and at 1 year. The periprocedural period was defined as the time from SA until 30 days after the procedure. Technical success and restenosis rates after the procedure were also analyzed.

Results

A total of 19 studies with 777 patients were identified. The technical success rate was 93% (95% CI 85% to 98%). The incidence of 30-day and 1-year stroke (all types) was 3% (95% CI 1% to 5%) and 5% (95% CI 4% to 8%), respectively. Thirty-day and 1-year mortality was found to be 1% (95% CI 0% to 2%) and 2% (95% CI 0% to 4%), respectively. The combined incidence of stroke or death was 5% (95% CI 3% to 8%) at 30 days, and 9% (95% CI 7% to 12%) at 1 year.

Conclusion

The findings suggest that SA might be a promising alternative treatment in the treatment of symptomatic ICAD due to its favorable technical profile, periprocedural safety, and long-term efficacy. A randomized clinical trial is warranted to compare the safety and efficacy of SA with 'gold standard' medical treatment.

Long-term Outcome of Angioplasty Using a Wingspan Stent, Post-Stent Balloon Dilation and Aggressive Restenosis Management for Intracranial Arterial Stenosis

PURPOSE

To investigate the long-term outcome of stent angioplasty for symptomatic severe intracranial artery stenosis.

METHOD

In this study 95 consecutive patients with intracranial atherosclerotic stenosis (>70%) underwent stent angioplasty using Wingspan stents. The primary endpoints were stroke or death within 30 days of the procedure and subsequent stroke attributed to the stented vessel. Disabling stroke was defined as stroke with a modified Rankin scale > 3. Secondary endpoints included transient ischemic attacks, contralateral stroke, nonstroke death, and other events. Patients underwent prestent balloon dilation with or without poststent balloon dilation, close restenosis follow-up, and selective retreatment, as required.

RESULT

The mean follow-up duration was 34.9 ± 23.3 months. Primary endpoint events occurred in 23% of the patients. The median infarction volume was 2.6 ml, and 11 (68%) of 16 infarctions were <5 ml in volume. Disabling stroke occurred in 3% of patients. The primary endpoint rates were 17.9% within 30 days and 2.1% from 30 days to 1 year. Secondary endpoint events occurred in 27.3% of the patients. Mean stenosis was reduced from 76.8 ± 6.1% to 7.5 ± 13.4%. Of 80 patients who underwent angiographic follow-up, 11 (14%) experienced restenosis (≥50%) and 7 (9%) exhibited restenosis-related symptoms of transient ischemic attack. The rate of symptomatic restenosis was significantly higher in patients who underwent prestent balloon dilation alone than in patients who underwent prestent and poststent balloon dilation (p = 0.016).

CONCLUSION

The postprocedural stroke rate was similar to that observed in the SAMMPRIS study. Symptomatic restenosis may be reduced by poststent dilation, close angiographic follow-up, and retreatment.

Percutaneous transluminal angioplasty using the novel drug-coated balloon catheter SeQuent Please NEO for the treatment of symptomatic intracranial severe stenosis: feasibility and safety study

Objectives

Intracranial arteriosclerotic disease is a relevant cause of ischemic stroke worldwide with a high recurrence rate despite best medical treatment. Following the SAMMPRIS trial, endovascular treatment has remained a second-line therapy. Meanwhile, there has been significant advances in device technology. SeQuent Please NEO is a novel polymer-free, drug-coated (paclitaxel/iopromide) balloon (DCB) primarily designed for cardiology. Because of its high flexibility and pushability, it may also be suitable for intracranial use. The aim of this study was to assess the feasibility and safety of SeQuent Please NEO DCB in symptomatic intracranial severe stenosis.

Methods

A single-center retrospective cohort study of patients with symptomatic intracranial severe stenosis treated with SeQuent Please NEO DCB was performed at a tertiary stroke center.

Results

Ten patients (all men, median age 73 years (IQR 69–77)) were included. Median pre-treatment stenosis grade was 78% (IQR 75–80%) with four internal carotid artery, two mid-basilar artery, and four vertebral artery lesions. Median post-treatment stenosis grade was 50% (IQR 45–53%). Successful angioplasty was achieved in all cases without technical failure. There were no cases of peri-procedural reocclusion and no deaths at median follow-up of 3 months (IQR 2–3).

Conclusion

In this pilot study, SeQuent Please NEO DCB was feasible and safe in the treatment of symptomatic intracranial severe stenosis. It might represent a promising alternative to medical treatment in selected cases.

New developments in clinical ischemic stroke prevention and treatment and their imaging implications

Acute ischemic stroke results from blockage of a cerebral artery or impaired cerebral blood flow due to cervical or intracranial arterial stenosis. Ischemic stroke prevention seeks to minimize the risk of developing impaired cerebral perfusion by controlling vascular and cardiac disease risk factors. Similarly, ischemic stroke treatment aims to restore cerebral blood flow through recanalization of an occluded artery or dilation of a severely narrowed artery that supplies cerebral tissue. Stroke prevention and treatment are increasingly informed by imaging studies, and neurovascular and cerebral perfusion imaging has become essential in in guiding ischemic stroke prevention and treatment. Here we review the latest advances in ischemic stroke prevention and treatment with an emphasis on the neuroimaging principles emphasized in recent randomized trials. Future research directions that should be explored in ischemic stroke prevention and treatment are also discussed.

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

Intracranial stenosis is a common cause of ischaemic strokes, in particular, in the Asian, African and Hispanic populations. The randomised multicentre study Stenting and Aggressive Medical Management for the Prevention of Recurrent stroke in Intracranial Stenosis (SAMMPRIS) showed 14.7% risk of stroke or death in the stenting group versus 5.8% in the medical group at 30 days, and 23% in the stenting group versus 15% in the medical group at a median follow-up of 32.4 months. The results demonstrated superiority of medical management over stenting and have almost put the intracranial stenting to rest in recent years. Of note, 16 patients (7.1%) in the stenting group had disabling or fatal stroke within 30 days mostly due to periprocedural complications as compared with 4 patients (1.8%) in the medical group. In contrast, 5 patients (2.2%) in the stenting group and 14 patients (6.2%) in the medical group had a disabling or fatal stroke beyond 30 days, indicating significant benefit of stenting if periprocedural complications can be reduced. Recently, the results of the Chinese Angioplasty and Stenting for Symptomatic Intracranial Severe Stenosis trial and the Wingspan Stent System Post Market Surveillance Study (WEAVE trial) showed 2%-2.7% periprocedural complications. It is time to evaluate the role of intracranial stenting for the prevention of disabling or fatal stroke.

Endovascular Treatment of Intracranial Atherosclerotic Stenosis: Current Debates and Future Prospects

Intracranial atherosclerotic stenosis (ICAS) is a common cause of transient ischemic attack (TIA) and ischemic stroke. Endovascular treatment, including balloon angioplasty alone, balloon-mounted stents, and self-expandable stent placement with or without prior angioplasty, is an alternative to medical treatment for the prevention of recurrent TIA or ischemic stroke in patients with ICAS. Although the SAMMPRIS and VISSIT trials supported medical management alone against endovascular treatments, both randomized controlled trials (RCT) were criticized due to flaws relating to patient-, intervention-, and operator-related factors. In this review, we discuss the current debate regarding these aspects and suggest approaches to solve current controversies in the future. In our opinion, endovascular treatment in carefully selected patients, individualized choice of endovascular treatment subtypes, and an experienced multidisciplinary team managing the patient in the pre-, peri- and post-procedural period have the potential to provide safe and efficious treatment of patients with symptomatic ICAS.

Angioplasty, Stenting and Other Potential Treatments of Atherosclerotic Stenosis of the Intracranial Arteries: Past, Present and Future

Although there is an intuitive appeal to treat symptomatic stenotic intracranial arteries with endovascular therapies such as angioplasty and stenting, current data from randomized trials show intensive medical therapy is far superior for preventing stroke. This is in large part due to the high risk of peri-procedural stroke from angioplasty and stenting. If angioplasty and stenting is to emerge as a proven treatment for intracranial stenosis, endovascular techniques will need to become much safer, identification of patients with intracranial stenosis who are at particularly high risk of stroke despite intensive medical therapy will need to be targeted, and well-designed randomized trials will be necessary to show endovascular therapy is superior to medical therapy in these high-risk patients.

Spanning from the West to East: An Updated Review on Endovascular Treatment of Intracranial Atherosclerotic Disease

Ischemic stroke is a major cause of morbidity and mortality, incurring significant cost. Intracranial atherosclerotic disease (ICAD) accounts for 10-15% of ischemic stroke in Western societies, but is an underlying pathology in up to 54% of ischemic strokes in Asian populations. ICAD has largely been treated with medical management, although a few studies have examined outcomes following endovascular treatment. Our objective was to summarize the major trials that have been performed thus far in regard to the endovascular treatment of ICAD and to provide direction for future management of this disease process. Systematic review of the literature from 1966 to 2015, was conducted in regard to intracranial angioplasty and stenting. Studies were analyzed from PubMed, American Heart Association and Society of Neurointerventional Surgery databases. SAMMPRIS and VISSIT are the only randomized controlled trials from which Western guidelines of intracranial stenting have been derived, which have displayed the superiority of medical management. However, pooled reviews of smaller studies and other nonrandomized trials have shown better outcomes with endovascular therapy in select patient subsets, such as intracranial vertebrobasilar stenosis or in the presence of robust collaterals. Suboptimal cases, including longer lesions, bifurcations and significant tortuosity tend to fair better with medical management. Medical management has been shown to be more efficacious with less adverse outcomes than endovascular therapy. However, the majority of studies on endovascular management included a diverse patient population without ideal selection criteria, resulting in higher adverse outcomes. Population analyses and selective utilization of endovascular therapy have shown that the treatment may be superior to other management in select patients.

2014 Chinese guidelines for secondary prevention of ischemic stroke and transient ischemic attack

Ischemic stroke and transient ischemic attack (TIA) are the most common cerebrovascular disorder and leading cause of death in China. The Effective secondary prevention is the vital strategy for reducing stroke recurrence. The aim of this guideline is to provide the most updated evidence-based recommendation to clinical physicians from the prior version. Control of risk factors, intervention for vascular stenosis/occlusion, antithrombotic therapy for cardioembolism, and antiplatelet therapy for noncardioembolic stroke are all recommended, and the prevention of recurrent stroke in a variety of uncommon causes and subtype provided as well. We modified the level of evidence and recommendation according to part of results from domestic RCT in order to facility the clinical practice.

Stroke Caused by Atherosclerosis of the Major Intracranial Arteries

Our goal in this review is to discuss the pathophysiology, diagnosis, and treatment of stroke caused by atherosclerosis of the major intracranial arteries. References for the review were identified by searching PubMed for related studies published from 1955 to June 2016 using search terms intracranial stenosis and intracranial atherosclerosis. Reference sections of published randomized clinical trials and previously published reviews were searched for additional references. Intracranial atherosclerotic disease is a highly prevalent cause of stroke that is associated with a high risk of recurrent stroke. It is more prevalent among blacks, Hispanics, and Asians compared with whites. Diabetes mellitus, hypertension, metabolic syndrome, smoking, hyperlipidemia, and a sedentary lifestyle are the major modifiable risk factors associated with intracranial atherosclerotic disease. Randomized clinical trials comparing aggressive management (dual antiplatelet treatment for 90 days followed by aspirin monotherapy and intensive management of vascular risk factors) with intracranial stenting plus aggressive medical management have shown medical management alone to be safer and more effective for preventing stroke. As such, aggressive medical management has become the standard of care for symptomatic patients with intracranial atherosclerotic disease. Nevertheless, there are subgroups of patients who are still at high risk of stroke despite being treated with aggressive medical management. Future research should aim to establish clinical, serological, and imaging biomarkers to identify high-risk patients, and clinical trials evaluating novel therapies should be focused on these patients.

History, Evolution, and Importance of Emergency Endovascular Treatment of Acute Ischemic Stroke

More than 800,000 people in North America suffer a stroke each year, with ischemic stroke making up the majority of these cases. The outcomes of ischemic stroke range from complete functional and cognitive recovery to severe disability and death; outcome is strongly associated with timely reperfusion treatment. Historically, ischemic stroke has been treated with intravenous thrombolytic agents with moderate success. However, five recently published positive trials have established the efficacy of endovascular treatment in acute ischemic stroke. In this review, we will discuss the history of stroke treatments moving from various intravenous thrombolytic drugs to intra-arterial thrombolysis, early mechanical thrombectomy devices, and finally modern endovascular devices. Early endovascular therapy failures, recent successes, and implications for current ischemic stroke management and future research directions are discussed.

Intracranial Stenting for Cerebrovascular Pathology

After reading this article, the participant should be able to:

Describe the use of stent-assisted angioplasty for intracranial atherosclerotic disease. Recall the present status of stent-assisted managment of intracranial aneurysms. Describe the role of stenting and its technical aspects in the treatment of arteriovenous fistulae and acute stroke.

Percutaneous transluminal angioplasty in a patient with internal carotid artery stenosis following gamma knife radiosurgery for recurrent pituitary adenoma

BACKGROUND

Intracranial vascular complications following radiosurgery are extremely rare.

CASE DESCRIPTION

We report a case of stenosis in the internal carotid artery 5 years after gamma knife radiosurgery for a recurrent pituitary adenoma. Percutaneous transluminal angioplasty was performed successfully with anatomical and functional improvement.

CONCLUSION

These results suggested the importance of monitoring for arterial stenosis in the long-term follow-up. Moreover, this is the first case of endovascular treatment as an effective therapy for intracranial arterial stenosis due to radiotherapy.

The technique of endovascular intracranial revascularization

Intracranial atherosclerosis was traditionally believed to carry a risk of stroke of 8% to 22% per annum. The annualized stroke rate in the recent stenting and aggressive medical management for preventing stroke in intracranial stenosis (SAMMPRIS) trial medical management arm was 12.2%. This trial was halted due to excessive periprocedural events in the stent arm. This stroke rate is still unacceptably, high and a treatment strategy is still needed. SAMMPRIS has no bearing on angioplasty alone. Angioplasty alone has always been our primary intervention for intracranial atherosclerosis and remains so to this day due to its relative simplicity, low complication rate, and efficacy. We have, however, made adjustments to our patient management regimen based on the results of SAMMPRIS. This paper outlines our current patient selection, procedural technique, and post-procedure management. The complications we have encountered while developing our technique are described along with how to avoid them and how to manage them. Our most recent results (since previous publications) are also discussed.

Primary angioplasty for symptomatic atherosclerotic middle cerebral artery stenosis

Objective

The objective of this study is to evaluate the clinical and angiographic outcomes after primary balloon angioplasty in patients with symptomatic middle cerebral artery (MCA, M1 segment) stenosis refractory to medical therapy.

Materials and Methods

Eleven patients with intracranial stenosis were treated with primary balloon angioplasty. All patients had MCA stenosis with recurrent transient ischemic attack (TIA). The indication for balloon angioplasty was patients with significant MCA stenosis: 1) age older than 18 years with recurrent or progressive TIA or infarction despite optimal medical therapy, including anti-coagulation, dual anti-platelet, and anti-lipid medication; 2) previous ischemic events or asymptomatic severe stenosis (more than 50%) with poor collateral cerebral circulation, or diminished cerebral perfusion on single photon emission computed tomography before and after administration of the intravenous dosage of acetazolamide.

Results

The median age of patients was 53 years (range 44-79). The technical success rate was 100%. Mean pretreatment stenosis degree was 83.63 ± 9.53% and 29.1 ± 15.4% before and after angioplasty, respectively. Procedural-related complications occurred in four of 11 patients (36%), but none of the patients had permanent neurological deficit. All patients were available for an average follow-up period of 19.4 ± 5.1 months. One patient had a stroke in the territory of angioplasty at two months after angioplasty. The stroke free survival rate at 30 days and 12 months was 100% and 91%, respectively. Restenosis over 50% was observed in three of 11 patients (27%); all were asymptomatic.

Conclusion

Intracranial angioplasty for symptomatic MCA stenosis refractory to medical therapy can be a treatment option to reduce the risk of further TIA or stroke.

Balloons in endovascular neurosurgery: history and current applications

The use of balloons in the field of neurosurgery is currently an essential part of our clinical practice. The field has evolved over the last 40 years since Serbinenko used balloons to test the feasibility of occluding cervical vessels for intracranial pathologies. Since that time, indications have expanded to include sacrificing cervical and intracranial vessels with detachable balloons, supporting the coil mass in wide-necked aneurysms (balloon remodeling technique), and performing intracranial and cervical angioplasty for atherosclerotic disease, as well as an adjunct to treat arteriovenous malformations. With the rapid expansion of endovascular technologies, it appears that the indications and uses for balloons will continue to expand. In this article, we review the history of balloons, the initial applications, the types of balloons available, and the current applications available for endovascular neurosurgeons.

Reviving Intracranial Angioplasty and Stenting "SAMMPRIS and beyond"

We review the methods and results of Stenting and Aggressive Medical Management for Preventing Recurrent Stroke (SAMMPRIS) and provide a critical review of its strengths and limitations. In SAMMPRIS, the aggressive medical treatment arm (AMT arm) did substantially better than the Wingspan Stenting plus aggressive medical management arm (WS+ arm). Complications in the first 30 days post intervention led to the disparity between treatment arms. A major contribution of SAMMPRIS was the added value that AMT and lifestyle change may provide, when compared to a precursor trial, Warfarin–Aspirin Symptomatic Intracranial Disease (WASID), designed to prevent stroke in persons with high-grade symptomatic intracranial occlusive disease, however, the results of neither of these two trials have ever been reproduced. On the other hand, we argue that technical limitations of the Wingspan stent system (WS System) and lack of an angioplasty only intervention arm may have led to a premature launch of the trial and early termination of the study. Future randomized trials with different devices and modified patient selection criteria are warranted.

Guidelines for the prevention of stroke in patients with stroke and transient ischemic attack: a guideline for healthcare professionals from the American Heart Association/American Stroke Association

The aim of this updated guideline is to provide comprehensive and timely evidence-based recommendations on the prevention of future stroke among survivors of ischemic stroke or transient ischemic attack. The guideline is addressed to all clinicians who manage secondary prevention for these patients. Evidence-based recommendations are provided for control of risk factors, intervention for vascular obstruction, antithrombotic therapy for cardioembolism, and antiplatelet therapy for noncardioembolic stroke. Recommendations are also provided for the prevention of recurrent stroke in a variety of specific circumstances, including aortic arch atherosclerosis, arterial dissection, patent foramen ovale, hyperhomocysteinemia, hypercoagulable states, antiphospholipid antibody syndrome, sickle cell disease, cerebral venous sinus thrombosis, and pregnancy. Special sections address use of antithrombotic and anticoagulation therapy after an intracranial hemorrhage and implementation of guidelines.

The case for angioplasty in patients with symptomatic intracranial atherosclerosis

Intracranial atherosclerotic disease (ICAD) is likely the most common cause of stroke worldwide and remains highly morbid even with highly monitored medical therapy. Recent results of the SAMMPRIS trial, which randomized patients to stenting plus aggressive medical management versus aggressive medical management alone have shown that additional treatment of intracranial atherosclerotic lesions with the Wingspan stent is inferior to aggressive medical management alone. In light of these results, there has been renewed interest in angioplasty alone to treat symptomatic ICAD. This article will briefly review the natural history of ICAD and discuss the possible future for endovascular treatment of ICAD with primary intracranial angioplasty in appropriately selected patients.

Endovascular Advances for Intracranial Occlusive Disease

Stroke is the fourth leading cause of death in the United States. Intracranial atherosclerotic disease accounts for 8%-10% of ischemic stroke in the United States. So far, surgical bypass has not proved to be superior to medical therapy. As both medical and endovascular therapies for intracranial atherosclerosis evolve, so too do the guidelines for treatment. Initial reports on the results of stent placement for symptomatic high-grade intracranial atherosclerotic disease were encouraging; however, recent trials suggest that initial medical management may be preferable. Currently, intracranial angioplasty and stenting for symptomatic intracranial atherosclerosis is now more controversial. Further trials are necessary to help determine which patients are ideal for endovascular therapies.

Atherosclerotic intracranial arterial stenosis: risk factors, diagnosis, and treatment

Intracranial atherosclerosis is one of the most common causes of stroke worldwide and is associated with a high risk of recurrent stroke. New therapeutic approaches to treat this high-risk disease include dual antiplatelet treatment, intensive management of risk factors, and endovascular therapy. Early data from randomised trials indicate that aggressive medical therapy is better than stenting for prevention of recurrent stroke in high-risk patients with atherosclerotic stenosis of a major intracranial artery. Nevertheless, there are subgroups of patients who remain at high risk of stroke despite aggressive medical therapy. Further research is needed to identify these high-risk subgroups and to develop more effective treatments. Non-invasive vascular imaging methods that could be used to identify high-risk patients include fractional flow on magnetic resonance angiography (MRA), quantitative MRA, and high-resolution MRI of the atherosclerotic plaque. Alternative therapies to consider for future clinical trials include angioplasty alone, indirect surgical bypass procedures, ischaemic preconditioning, and new anticoagulants (direct thrombin or Xa inhibitors).

Treatment of intracranial arterial stenosis

Intracranial stenosis accounts for 8-10% of ischemic strokes in the USA. Treatment of intracranial stenosis with extracranial-to-intracranial bypass surgery was investigated as a therapy in the 1980s, but was shown to be no better than aspirin alone. The Warfarin vs Aspirin for Symptomatic Intracranial Disease study found a 12% per year risk of recurrent stroke for symptomatic lesions of 50% or higher, with the majority of strokes occurring in the first year. Warfarin was no better than aspirin in the prevention of recurrent stroke and had a higher risk of serious bleeding and death. Subgroup analysis showed that patients with the highest risk of recurrent stroke included those with 70% or more stenosis and/or recent symptoms and women. Angioplasty and stenting of intracranial stenosis have been undergoing rapid evolution in technology and are emerging as a promising therapy. Current treatment recommendations include antiplatelet agents, with consideration for angioplasty alone or angioplasty and stenting in cases refractory to medical therapy.

Percutaneous Treatment of Severe Intracranial Carotid and Middle Cerebral Artery Stenosis

Due to the lack of efficacy and durability data from prospective, randomized, multicenter trials, intracranial stenting remains investigational and should be used only in carefully selected patients after thorough evaluation of their clinical and anatomic factors. Stenting should not be performed in chronic total occlusions and asymptomatic lesions and generally should be avoided in very old patients, especially those with underlying dementia and severe calcification of their vessels. Symptomatic patients with angiographically documented greater than 70% stenosis and who have failed medical therapy are appropriate candidates for intracranial angioplasty and stenting and should be enrolled in clinical trials when possible.

National trends in utilization and outcomes of angioplasty and stenting for revascularization in intracranial stenosis

INTRODUCTION

Angioplasty and intracranial stenting (ICS) are both endovascular revascularization procedures that have emerged as treatment options for intracranial atherosclerotic disease (ICAD). Some believe angioplasty alone is better, while others believe stenting is better. This study examines recent trends in utilization and outcomes of angioplasty alone and ICS in the United States using a population-based cohort.

METHODS

The National Inpatient Sample (NIS) database was queried for patients with ICAD who underwent angioplasty or ICS from 2005 to 2010.

RESULTS

There were 1115 patients (angioplasty: n=495, ICS: n=620) with ICAD who underwent endovascular revascularization. Over time, the number of endovascular revascularization procedures increased. The percentage of symptomatic patients (p=0.015) as well as in the number of comorbidities of patients treated (p<0.001) also increased. Combined post-procedure stroke and death rates were 16% and 28.9% for angioplasty and ICS, respectively (p<0.001). A larger percentage of angioplasty patients presented symptomatically compared to those who underwent ICS (p<0.001).

CONCLUSION

Angioplasty appears to be associated with higher rates of peri-procedural complications; however, that may represent patient selection bias. Further studies are needed to identify patients who would benefit from revascularization and to clarify the roles of angioplasty and ICS.

The challenge of stroke prevention with intracranial arterial stenosis

Patients with symptomatic intracranial atherosclerotic disease have a high risk of recurrent stroke, and secondary prevention in these patients remains a challenge. Aggressive medical management of vascular risk factors is safe and effective for most high risk patients, but the role of endovascular and surgical therapies still remain uncertain. Future studies may identify novel therapeutic strategies for patients with intracranial atherosclerotic disease, but aggressive risk factor control remains the mainstay of evidenced-based treatment at this time.

Endovascular treatment of intracranial atherosclerotic disease

Stroke is the third leading cause of death in the United States. Intracranial atherosclerotic disease plays a role in cerebrovascular accidents, with well-characterized modifiable and nonmodifiable risk factors. Surgical bypass has so far not proved to be superior to medical therapy. Both medical and endovascular therapies for intracranial atherosclerosis have evolved since the initial off-label use of cardiac devices for its treatment. Initial reports on the results of stent placement for symptomatic high-grade intracranial atherosclerotic disease were initially encouraging. However, debate remains as to the optimal treatment of symptomatic intracranial atherosclerotic disease.

Recent advances in endoluminal revascularization for intracranial atherosclerotic disease

More than 750,000 strokes occur annually in the United States. Of these, 8-10% are due to intracranial atherosclerosis. Less than 50% of patients with strokes from intracranial atherosclerosis will have a transient ischemic attack. For those patients with symptomatic intracranial atherosclerosis, the prognosis is poor; and the recent Warfarin-Aspirin Symptomatic Intracranial Stenosis (WASID) trial results have demonstrated the high risk of warfarin without clear benefit. Intracranial angioplasty and stenting is emerging as a viable and effective treatment alternative for patients with symptomatic intracranial stenosis. Advances in stent design, endovascular wires, and catheters and balloons are allowing endovascular surgeons to safely treat intracranial atherosclerosis. Wider clinical experience has led to refinement of patient selection and endoluminal techniques. Drug eluting-stents have the promise of decreasing the risk of restenosis. In this review, the most recent clinical, laboratory, and technical details for the treatment of intracranial angioplasty and stenting are discussed.

Preliminary evidence supporting the safety of drug-eluting stents in neurovascular disease

OBJECTIVE

Restenosis is a significant complication of stent placement. With coronary revascularization, drug-eluting stents have significantly decreased the incidence of in-stent stenosis and, therefore, the morbidity of the procedure. Restenosis is potentially a significant problem for neurovascular disease. We therefore report our institutional experience on the use of drug-eluting stents for the management of cerebrovascular insufficiency.

METHODS

Over a period of 2 years, 19 patients underwent extra- and intracranial drug-eluting stent placement for intra- and extracranial atherosclerotic disease. There were 12 males and seven females aged between 36 and 83 years old (mean 65). Thirteen heparin, three rapamycin, and three taxus-coated stents were placed. There were five intracranial internal carotid arteries, two intracranial vertebral arteries, three mid-basilar, six of vertebral artery origin and three middle cerebral artery stents utilized. No complications occurred.

RESULTS

There was one case of re-stenosis associated with recurrent symptoms requiring repeat drug eluting stent placement. No other patients have developed new or recurrent neurological symptoms. Five of six vertebral artery origin stents were placed with distal protection to prevent embolic complications.

CONCLUSION

Intracranial and extracranial drug-eluting stent placement appears to be a safe alternative to the medical management of atherosclerotic disease of the vertebrobasilar and carotid systems. However, further randomized studies are needed to examine the effectiveness and safety of this procedure.

Wingspan Stenting for Intracranial Atherosclerotic Stenosis

BACKGROUND:

Intracranial atherosclerotic stenosis (ICAS) is responsible for 9% to 37% of ischemic strokes.

OBJECTIVE:

To evaluate the clinical outcome and risk factors for in-stent restenosis (ISR) after treatment of ICAS with a Wingspan stent.

METHODS:

Seventy-seven patients with 79 total target ICAS &gt; 60% (mean, 79.9 ± 8.4%; symptomatic ICAS, 96.2%) underwent attempted treatment with Wingspan stenting between March 2010 and March 2011. A retrospective review of the prospectively registered data was conducted to assess the risk factors for ISR and the clinical outcomes of these patients.

RESULTS:

The 30-day transient ischemic attack/stroke and death rates were 5.3% (95% confidence interval [CI], 0.1-10.5) and 0%, respectively. All patients but 1 were followed up clinically for a mean of 18.9 months (range, 12–23 months). During the period, cumulative transient ischemic attack/stroke and death rates were 8.1% (95% CI, 1.7-14.5) and 0%, respectively. Only 1 patient suffered a disabling stroke (subarachnoid hemorrhage), which was associated with retreatment of an ISR with a drug-eluting balloon-expandable stent. Follow-up angiography was available in 69 treated vessels (89.6%) at 3 to 24 months (median, 12 months). Binary ISR rate was 24.6%, of which 17.6% (3 of 17 cases) was symptomatic. Rapid balloon inflation (95% CI, 5.490-530.817) and longer length of stenosis (95% CI, 1.093-1.891) were independent risk factors for ISR.

CONCLUSION:

Wingspan stenting may be effective for appropriately selected ICAS patients. Rapid balloon inflation and longer lengths of stenosis were independent risk factors for ISR.

[Treatment of high grade intracranial stenoses]

Intracranial stenosis is the cause of 10 % of strokes. Besides medicinal treatment, intracranial bypass surgery, percutaneous transluminal angioplasty and stenting are available treatment approaches. According to the 2005 published WASID trial antiplatelets should be preferred to oral anticoagulation in secondary preventive therapy of ischemic stroke; however patients with high grade intracranial stenosis still have a poor prognosis. Intracranial bypass surgery, which was taken into account as a treatment option even in 1985, showed a generally worse outcome in relation to medicinal therapy. Intracranial angioplasty and stenting, representing improvements in endovascular treatment, were proven to be effective and feasible treatment approaches for patients with symptomatic high grade intracranial stenosis. Within the scope of the SAMMPRIS trial published in 2011, which propagated an advantage of aggressive medicinal treatment versus endovascular therapy, a retrospective study was performed at the department of neuroradiology of the Homburg University of Saarland.

Endovascular treatment of symptomatic intracranial atheromatous stenosis: a single center study of 21 consecutive cases

OBJECTIVES

This retrospective single-center study evaluated the technical success as well as the periprocedural and long-term complications of angioplasty with stenting of symptomatic intracranial atheromatous stenosis.

PATIENTS AND METHODS

From January 2005 to December 2010, 21 patients were treated by angioplasty with stent implantation for symptomatic atheromatous intracranial stenosis greater or equal to 50% at least 7 days after a stroke.

RESULTS

The median population age was 65 years (range: 41-88 years), and 76% (16/21) of the candidates had a history of transient ischemic attack (TIA) or stroke before the event qualifying them for an endovascular procedure. In addition, 86% (18/21) were taking antithrombotic medication at the time of the qualifying event. Technical success was obtained in all cases. The periprocedural stroke or death rate was 9.5% (2/21), and there was no other stroke or death after 30 days during the mean follow-up of 1.4 years.

CONCLUSION

Endovascular treatment of symptomatic intracranial atherothrombotic stenosis can lead to severe complications, particularly during the periprocedural period, but it also represents the only alternative treatment for patients who fail with medical therapy. Future studies need to focus on improvement of periprocedural complications. Essentially, this should include more rigorous selection of candidates as well as a better understanding of the pathophysiological mechanism(s) of the ischemic phenomenon related to stenosis.

Flow failure from intracranial atherosclerotic disease: a rationale for endovascular intervention in a population with recurrent symptoms despite maximal medical therapy

The Stenting and Aggressive Medical Management for Preventing Recurrent stroke in Intracranial Stenosis (SAMMPRIS) trial, the first randomized trial to compare best medical therapies with angioplasty and stenting, was halted prematurely owing to a 30-day stroke rate of 14.7% in the angioplasty and stenting arm compared with 5.8% in the medical management arm. These results have led to a paradigm shift away from interventional therapies and back to dual antiplatelet therapy and aggressive medical therapies only for these patients. However, there appears to be a subset of patients with intracranial atherosclerotic disease (ICAD) who are different from the general SAMMPRIS cohort and are defined by flow failure from severe intracranial arterial stenosis resulting in recurrent ischemic symptoms despite maximal medical therapy. Offering the option of endovascular revascularization seems appropriate in this patient population, given their recurrent ischemic events regardless of aggressive medical therapies. This paper provides a rationale for reconsidering the role of interventional therapies in patients with critical intracranial stenosis and presents four patients with flow failure from ICAD and persistent symptoms of ischemia, regardless of dual antiplatelet and adjuvant medical therapies, who subsequently improved with angioplasty. Consideration of alternative patient populations and treatment paradigms seems to carry particular relevance now as the endovascular treatment of intracranial atheromatous disease is currently receiving intense scrutiny by those medical specialties involved in the care of stroke patients, as well as the public at large.