Drug eluting stents for symptomatic intracranial and vertebral artery stenosis

Endovascular treatment of symptomatic severe intracranial atherosclerotic stenosis with a novel intracranial dedicated drug-eluting stent: a more effective treatment approach

Background

Endovascular treatment of severe intracranial atherosclerotic stenosis (ICAS) using coronary drug-eluting stents (DESs) significantly reduces the risk of in-stent restenosis (ISR) and stroke recurrence. However, there are few reports regarding the treatment of ICAS with intracranial dedicated DES. Herein, we present our experience with the feasibility, safety, and medium-term follow-up outcomes of a novel intracranial DES, named NOVA stent, in patients with symptomatic severe ICAS (≥70%).

Methods

From December 2021 to May 2022, patients with symptomatic severe ICAS who underwent implantation of the NOVA stent in our institution were retrospectively analyzed for procedural results, perioperative complications, imaging and clinical follow-up outcomes.

Results

Twenty-four patients, 16 (66.7%) with anterior circulation lesions and 8 (33.3%) with posterior circulation lesions, were enrolled. All patients with intracranial ICA (n = 6), middle cerebral artery (n = 10), basilar artery (n = 3), intracranial vertebral artery (n = 3), and the vertebrobasilar junction (n = 2) stenosis were treated successfully using NOVA stents. The severity of stenosis ranged from 75 to 96% (mean 85.9%) before treatment and this was reduced to 0 to 20% (mean 8.6%) immediately after stent placement. Symptomatic distal embolism occurred in one case; however, there were no other perioperative complications. The mean follow-up duration was 12.2 ± 1.06 months. No symptomatic ischemic events occurred during follow-up. Follow-up cerebral angiography was performed in 22 of 24 patients (91.7%), and significant ISR occurred in one patient (4.2%).

Conclusion

Our results demonstrate that implantation of the novel intracranial DES NOVA in severe ICAS is feasible, safe, and effective in selected cases, reducing the incidence of ISR, and showing excellent midterm clinical outcomes, providing a promising option for ICAS treatment.

A Systematic Review and Meta-Analysis of Drug Eluting Stents for Safety and Efficacy in Intracranial Atherosclerotic Disease

BACKGROUND

Advancements in arterial stenting technology have challenged prior notions favoring medical management for intracranial atherosclerotic disease (ICAD). Where previous conclusions were drawn from bare metal stent (BMS) technology, recent studies suggest drug-eluting stents (DES) are favorable due to their anti-proliferative effect, which reduces vascular remodeling.

METHODS

We conducted a systematic review and meta-analysis of the literature prior to August 2023 reviewing all reports of ICAD treated with DES. Our target outcomes were incidence of any stroke, transient ischemic attack (TIA), or death within 30 days (postprocedural complications), ischemic stroke in the territory of the qualifying artery beyond 30 days (long-term complications), radiographically detected in-stent restenosis rate (ISR), and symptomatic ISR during follow-up. A subgroup analysis further stratified preprocedural mean stenosis above and below 70% into severe and moderate cohorts, respectively.

RESULTS

PubMed, Web of Science, Cochrane and EMBASE query identified 527 candidate articles, from which 14 studies met inclusion criteria for a total of 607 patients and 640 ICAD lesions. Incidence of postprocedural complications was 7.3% (95% CI 3.9-11.7%) with subgroup analysis demonstrating significantly higher incidence in the severely stenotic group [9.0% (95% CI 4.7-14.5%)] than the moderately stenotic group [3.0% (95% CI 0.7-6.8%)]. Long-term complications were 1.2% (95% CI 0.4-2.3%). Radiographic ISR was 3.5% (95% CI 1.4-6.3%) and symptomatic ISR was 0.3% (95% CI 0.0-1.5%).

CONCLUSIONS

Our systematic review and meta-analysis suggest that DES can effectively reduce the risk of ISR and may be a viable treatment modality to reduce long-term complications in refractory ICAD patients.

The resolute Onyx drug eluting stent for neurointervention: A technical series

INTRODUCTION

Current methods for angioplasty and stenting of the intracranial vasculature for neurointervention are limited. The Wingspan Stent System is Food and Drug Administration (FDA) approved with human device exemption for a limited patient group and despite numerous prospective registries and trials demonstrating reasonable safety, still carries warnings from the FDA for its use. Given these limitations, we present the technical nuances and outcomes of the off-label use of the Resolute Onyx drug-eluting stent (DES) for neurointerventional purposes.

METHODS

Retrospective chart review of all patients undergoing a neurointerventional procedure with the Resolute Onyx DES was done from January 2017-2021. The Resolute Onyx is a coronary balloon-mounted drug-eluting (zotarolimus) single wire laser cut stent. Technical details and procedural outcomes were collected.

RESULTS

In total 40 patients had attempted placement of the Resolute Onyx DES with procedural success in 95% of patients. The most common vessel stented was the basilar artery, 30% (12/40). The most common indication was intracranial atherosclerotic disease in 62.5% (25/40) patients, followed by acute stroke in 17.5% (7/40) of patients. The technical and procedural outcomes were excellent with only one technical complication (2.5%).

CONCLUSIONS

This series describes the initial technical safety and utility of utilizing a new generation balloon-mounted drug-eluting stent for neurointerventional purposes. This stent offers the potential for improved navigability, delivery, and outcomes compared to current neurointerventional options and warrants further study.

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.

Use of drug-eluting, balloon-expandable resolute onyx coronary stent as a novel treatment strategy for vertebral artery ostial stenosis: Case series

INTRODUCTION

Vertebral artery (VA) ostial stenosis is notoriously difficult to treat using bare-metal stents owing to high rates of restenosis and stent kinking and breakage. We investigated the safety and effectiveness of treatment with a drug-eluting, balloon-expandable coronary stent (Resolute Onyx, Medtronic).

METHODS

Our prospectively maintained database was retrospectively searched for consecutive patients diagnosed with VA ostial stenosis who underwent Resolute Onyx stenting with/without angioplasty between January 1, 2015 and January 1, 2022. Patient demographics and clinical and radiographic presentations were recorded. Occlusion location, stenosis severity, contralateral disease, devices used, and intraprocedural and postprocedural complications were noted. Outcomes were assessed based on new or recurrent stroke, transient ischemic attack (TIA), or intracranial hemorrhage (ICH). Patients were followed up clinically and with radiographic imaging for in-stent stenosis.

RESULTS

Twenty-six patients were included in our study (21 men [80.8%]; mean age 70.3 ± 9.8 years). Symptomatic patients presented with TIA (11/26, 42.3%) and stroke (10/26; 38.5%). Mean stenosis in the study cohort was 74.9 ± 13.0%. One (3.8%) intraprocedural complication was encountered whereby the stent failed to open despite several attempts and was exchanged with a new one without issues. No in-hospital postprocedure stroke, TIA, or mortality was reported. During a mean 16.2 ± 13.6 months' follow up, two patients developed symptomatic in-stent restenosis that was treated with balloon angioplasty.

CONCLUSIONS

We report the first case series of Resolute Onyx drug-eluting stenting including 30-day postprocedure stroke/TIA rates and clinical/radiographic follow up and demonstrate safe and effective treatment of symptomatic and asymptomatic VA ostial stenosis.

Effect of a Drug-Eluting Stent vs. Bare Metal Stent for the Treatment of Symptomatic Intracranial and Vertebral Artery Stenosis

Background

For patients with symptomatic intracranial and vertebral artery stenosis who receive endovascular treatment, in-stent restenosis (ISR) is associated with the recurrence of ischemic stroke. This study evaluated a drug-eluting stent (DES) vs. bare metal stent (BMS) for the treatment of symptomatic intracranial and vertebral artery stenosis.

Methods

The trial was a multicenter, 1:1 randomized, prospective feasibility clinical trial with 10 participating centers in China from March 2014 to October 2015. Eligible patients had symptomatic intracranial and vertebral artery stenosis (70%−99%) and had medical drug treatment failure. The primary endpoint was the rate of in-stent restenosis at 180 days of randomization. The secondary endpoint was a composite of the following two outcomes: (1) ischemic stroke or transient cerebral ischemia (TIA) in the same territory as the presenting event (distal to the target lesion) between 30 days and 1 year after randomization and (2) successful stent implantation. The safety outcome was the presence of stroke in any territory and death within 30 days of randomization or adverse events. Group t-tests or Wilcoxon rank-sum tests were used for the intergroup comparison of quantitative data according to the data distribution. The chi-square test or exact probability method was used for the classification data. The Wilcoxon rank-sum test or CMH test was used for the categorical data.

Results

We enrolled 188 patients at 10 medical centers in China (92 assigned to the DES group and 96 to the BMS group). The mean age of the 188 study participants was 61.6 years (range, 38–75 years); 152 participants (80.9%) were male. There were 28 patients (43.8%) with an ISR at 180 days in the BMS group and 10 patients (14.5%) in the DES group [risk difference, 29.3% (95% CI, 14.5%−44.0%); P = 0.001]. The percent of patients with ischemic stroke or TIA in the same territory between 30 days and 1 year was 5.2% (5/96) in the BMS group and 2.2% (2/92) in the DES group [risk difference, 3.0%; (95% CI, −2.3% to 8.2%); P = 0.354]. The percent of patients with successful stent implantation was 99.0% (95/96) in the BMS group and 97.8% (90/92) in the DES group [risk difference, 1.1%; (95% CI, −1.7% to 3.9%); P = 0.584]. In total, five patients (5.2%) in the BMS group and three patients (3.3%) in the DES group [risk difference, 1.9%; (95% CI, −2.3% to 6.1%); P = 0.721] had stroke in any territory and death within the 30-day follow-up. Total adverse events occurred 167 times in 72 patients (75.0%) in the BMS group compared with 114 times in 59 patients (64.1%) in the DES group [risk difference, 10.9%; (95% CI, −0.1% to 21.7%); P = 0.115].

Conclusions

Among patients with symptomatic intracranial arterial stenosis and vertebral artery stenosis, the use of a drug-eluting stent compared with a bare metal stent resulted in a decreased risk of ISR, similar successful stent implantation, and similar adverse events. These findings support the use of a drug-eluting stent for patients with symptomatic intracranial arterial stenosis and vertebral artery stenosis.

Clinical Trial Registration

http://www.chictr.org.cn/showproj.aspx?proj=148272, identifier: ChiCTR2200055925.

Comparison of Drug-Eluting Stent With Bare-Metal Stent in Patients With Symptomatic High-grade Intracranial Atherosclerotic Stenosis: A Randomized Clinical Trial

Importance

In-stent restenosis (ISR) is the primary reason for stroke recurrence after intracranial stenting in patients who were treated with a standard bare-metal stent (BMS). Whether a drug-eluting stent (DES) could reduce the risk of ISR in intracranial atherosclerotic stenosis (ICAS) remains unclear.

Objective

To investigate whether a DES can reduce the risk of ISR and stroke recurrence in patients with symptomatic high-grade ICAS.

Design, Settings, and Participants

A prospective, multicenter, open-label randomized clinical trial with blinded outcome assessment was conducted from April 27, 2015, to November 16, 2018, at 16 medical centers in China with a high volume of intracranial stenting. Patients with symptomatic high-grade ICAS were enrolled, randomized, and followed up for 1 year. Intention-to-treat data analysis was performed from April 1 to May 22, 2021.

Interventions

Patients were randomly assigned to receive DES (NOVA intracranial sirolimus-eluting stent system) or BMS (Apollo intracranial stent system) treatment in a 1:1 ratio.

Main Outcomes and Measures

The primary efficacy end point was ISR within 1 year after the procedure, which was defined as stenosis that was greater than 50% of the luminal diameter within or immediately adjacent to (within 5 mm) the implanted stent. The primary safety end point was any stroke or death within 30 days after the procedure.

Results

A total of 263 participants (194 men [73.8%]; median [IQR] age, 58 [52-65] years) were included in the analysis, with 132 participants randomly assigned to the DES group and 131 to the BMS group. The 1-year ISR rate was lower in the DES group than in the BMS group (10 [9.5%] vs 32 [30.2%]; odds ratio, 0.24; 95% CI, 0.11-0.52; P < .001). The DES group also had a significantly lower ischemic stroke recurrence rate from day 31 to 1 year (1 [0.8%] vs 9 [6.9%]; hazard ratio, 0.10; 95% CI, 0.01-0.80; P = .03). No significant difference in the rate of any stroke or death within 30 days was observed between the DES and BMS groups (10 [7.6%] vs 7 [5.3%]; odds ratio, 1.45; 95% CI, 0.54-3.94; P = .46).

Conclusions and Relevance

This trial found that, compared with BMSs, DESs reduced the risks of ISR and ischemic stroke recurrence in patients with symptomatic high-grade ICAS. Further investigation into the safety and efficacy of DESs is warranted.

Trial Registration

ClinicalTrials.gov Identifier: NCT02578069.

Safety and Efficacy of Rapamycin-Eluting Vertebral Stents in Patients With Symptomatic Extracranial Vertebral Artery Stenosis

Background and Purpose: Drug-eluting stents generally have superior performance to bare metal stents in the treatment of vertebral artery stenosis (VAS). This prospective, multicenter, and single-arm clinical trial was initiated to assess in-stent restenosis (ISR) and midterm outcome after rapamycin-eluting stent placement in patients with symptomatic extracranial VAS.

Methods: The subjects underwent angiographic follow-up at 6 months and final clinical follow-up at 12 months. The primary efficacy endpoint was ISR at 6 months. Secondary endpoints included technical success, target lesion-related transient ischemic attack (TIA), stroke, or death, and all-cause TIA, stroke, or death during the 12-month follow-up period.

Results: A total of 104 stents were implanted in the 101 patients and 83 patients (82.2%) completed angiographic follow-up at 6 months. The technical success rate was 86.1% (87/101); mean in-stent stenosis rate was 25.1 ± 17.1% and ISR rate was 5.9% (95% CI: 0.8–10.9%). All the patients with ISR were completely asymptomatic and no stent fractures were observed during angiographic follow-up. At the 12-month clinical follow-up, target lesion-related TIA, stroke, or death had occurred in two (2.0%) patients and all-cause TIA, stroke, or death had occurred in six (6.1%) patients.

Conclusion: The placement of rapamycin-eluting stents in patients with symptomatic extracranial VAS yields favorable ISR results and showed a trend of favorable safety outcomes including low rates of perioperative complications and late stroke. However, further study is needed to establish the long-term clinical benefits of this stent in the treatment of VA disease.

Long-term outcomes of drug-eluting stent implantation in patients with symptomatic extra- and intracranial atherosclerotic stenoses

Objective

Implantation of drug-eluting stents (DES) for extra- and intracranial atherosclerotic stenoses is an emerging topic. It has the potential benefit of preventing recurrent stroke with a reduced rate of in-stent restenosis (ISR).

Methods

Patients who underwent extra- or intracranial stenting using DES in a single institution were retrospectively reviewed with long-term angiographic and clinical follow-up data.

Results

Twenty-one patients, 9 (42.9%) with extracranial lesions and 12 (57.1%) with intracranial lesions, were included. The most common symptom was cerebral infarction (71.4%), followed by vertebrobasilar insufficiency (19.1%) and transient ischemic attack (9.5%). All patients achieved technical success, with the mean degree of stenosis of 85.9±6.3% before the procedure and 19.5±5.9% after the procedure. All patients showed clinical improvement and no symptomatic recurrence was reported during the mean clinical follow-up period of 45.5±8.9 months. The significant ISR was observed in one patient (4.8%) during the mean radiological follow-up period of 42.8±10.0 months.

Conclusions

Implantation of drug-eluting stents for symptomatic extra- and intracranial atherosclerotic stenoses is feasible and has the potential benefit of reducing the rate of ISR.

Initial Experience With the Next-Generation Resolute Onyx Zotarolimus-Eluting Stent in Symptomatic Intracranial Atherosclerotic Disease

Background and Purpose: Intracranial atherosclerotic disease (ICAD) is a common cause of stroke worldwide. Although there are different endovascular options for the treatment of symptomatic ICAD (sICAD), it is still controversial. Herein, we aim to study the safety and efficacy of a new generation of drug-eluting balloon-mounted stent (DES); Resolute (R) onyx DES in the treatment of sICAD.

Methods: A prospectively maintained neuroendovascular procedures database in a high-volume comprehensive stroke center was reviewed from October 2019 through January 2020. Patients were included if they had sICAD (≥70% stenosis), failed medical management, and underwent intracranial stenting with R-onyx DES. Technical success was defined as the ability to deploy the device at the desired location and achievement of <30% residual stenosis. The primary outcome was the occurrence of complications within 72 h of the procedure (strokes, ischemic or hemorrhagic; and mortality). Secondary outcomes included rates of symptomatic and angiographic recurrence within 6 months of the procedure.

Results: A total of 18 consecutive patients (mean age, 66.6 years; 44.4% were females and 94.4% were Hispanic) were eligible for the analysis. Indication for treatment was recurrent strokes in 13 and recurrent transient ischemic attack (TIA) in 5. A total of 22 symptomatic lesions with a mean baseline stenosis percent (84.9 ± 9.6) were treated using 23 R-onyx DES in 19 procedures. All procedures were done under general anesthesia with 100% technical success, and no reported periprocedural strokes or death. Among 13 patients who had clinical follow-up, 1 (7.7%) patient had TIA. There were no reported ischemic or hemorrhagic strokes. Angiographic follow-up for 9 (50%) patients showed no in-stent restenosis.

Conclusion: The use of R-onyx DES in the treatment of sICAD is safe with high technical success rates. Large prospective multicenter trials with long-term follow-up are warranted.

Efficacy and safety of drug-eluting stent for the intracranial atherosclerotic disease: A systematic review and meta-analysis

Drug-eluting stent (DES) is a potential endovascular treatment for patients with symptomatic intracranial atherosclerotic disease (sICAD). However, evidence regarding the treatment of ICAD with DES is lacking. We systematically searched Pubmed, Embase, Cochrane database (before 2017-12-21) for literature reporting the application of DES in the treatment of sICAD. The main outcomes were as follows: the incidence of any stroke or death within 30 days (perioperative complications), ischemic stroke in the territory of the qualifying artery beyond 30 days (long-term complications), in-stent restenosis rate (ISR) and symptomatic ISR during follow-up. Those studies with mean stenosis rate greater than 70% and less than 70% were defined as severe and moderate stenosis group, respectively. The random effect model was used to pool the data. Of 518 articles, 13 studies were eligible and included in our analysis (N = 336 patients with 364 lesions). After the implantation of DES, perioperative complications (mortality = 0) occurred in 6.0% (95%CI 2.0%-11.9%), long-term complications occurred in 2.2% (95%CI 0.7%-4.5%), ISR rate was 4.1% (95%CI 1.6%-7.7%) and the symptomatic ISR rate was only 0.5% (95%CI 0-2.2%). In addition, subgroup analysis showed that the perioperative complication rate in severe stenosis group [10.6% (95%CI 6.5%-15.7%)] was significantly (p < 0.01) higher than that in moderate stenosis group [1.0% (95%CI 0.3%-3.5%)]. In summary, endovascular DES implantation is a relatively safe and effective method compared with stents or medical management group in SAMMPRIS and VISSIT trials. However, a higher preoperative stenosis rate may imply a higher risk of perioperative complications. Further studies are needed.

Invasive treatment in peripheral artery disease

Invasive treatment in peripheral artery disease (PAD) has evolved as a viable alternative to surgical treatment. However, beyond the common pathophysiological substrate, as far as treatment is concerned, each site of atherosclerotic disease (subclavian and vertebral arteries; carotid arteries; intracranial arterial tree; renal arteries; lower extremity arteries) features unique characteristics. Treatment options include medical treatment, endovascular management and/or surgery. Sound clinical evaluation is required as individual patient assessment often limits intervention options, while available data regarding benefits of invasive and surgical management are questioned by advances in medical treatment. In the present article, we aim to summarize existing evidence and guidance on the role of invasive procedures in PAD.

Internal carotid artery stenting for intracranial atherosclerosis

Intracranial atherosclerotic disease is a significant cause of stroke in the United States. Much like coronary atherosclerosis, this disease leads to arterial stenosis secondary to the buildup of lipid-based plaques in intracranial vessels. Ischemic stroke may occur following thromboembolic events near the site of stenosis or from watershed ischemia secondary to cerebral hypoperfusion. While this disease has been treated with intracranial angioplasty and stenting and cerebrovascular bypass surgery, the current literature supports aggressive medical management with dual antiplatelet therapy, treatment of comorbidities such as hypertension, diabetes, and hyperlipidemia, and lifestyle modification. Intracranial angioplasty and stenting is reserved for cases of medical failure.

Advances and Innovations in Revascularization of Extracranial Vertebral Artery

Revascularization of the extracranial vertebral artery has evolved significantly since the adoption of endovascular techniques. The current neurosurgical armamentarium includes microsurgical and endovascular approaches. The indications for each treatment modality, however, still need to be further delineated. In contrast to carotid artery endarterectomy and carotid artery angioplasty/stenting, there is limited comparative evidence on the efficacy of medical, open, and endovascular treatment of atherosclerotic disease of the extracranial vertebral artery. More recently, drug-eluting stents have gained momentum after high rates of in-stent restenosis have been reported with bare metal stents placed in the vertebral artery. In this article, we discuss the indications, clinical assessment, and surgical nuances of microsurgical and endovascular revascularization for atherosclerotic disease of the extracranial vertebral artery. Despite a general tendency to consider endovascular treatment in the majority of patients, ultimately, open and endovascular revascularization of extracranial vertebral artery should be regarded as complementary therapies and both treatment options need to be discussed in selected patients.

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).

Unique remodeling processes after vascular injury in intracranial arteries: analysis using a novel mouse model

The effectiveness of angioplasty and stenting in intracranial atherosclerotic diseases is controversial due to high rates of delayed restenosis and hemorrhage compared with extracranial arteries. However, the mechanisms underlying these differences are still unclear, because their pathophysiology is yet to be examined. To address this issue, we established a novel vascular injury model in the intracranial internal carotid arteries (IICAs) in mice, and analyzed the remodeling process in comparison to that of the femoral arteries (FAs). In IICAs, neointimal hyperplasia was observed from day 14 and grew until day 56. Although smooth muscle cells (SMCs) emerged in the neointima from day 28, SMCs in the injured media were continuously lost with eventual extinction of the media. Re-endothelialization was started from day 7 and completed on day 28. Accumulation of macrophages was continued in the adventitia until day 56. Compared with FAs, the following points are unique in IICAs: (1) delayed continuous formation of neointima; (2) accumulation of macrophages in the media on day 14; (3) continuous loss of SMCs in the media followed by extinction of the media itself; and (4) continuously growing adventitia. These pathophysiologic differences might be associated with unfavorable outcomes in percutaneous transluminal angioplasty and stenting in intracranial arteries.

Acute interventional recanalisation of vertebrobasilar stenoses by angioplasty: complications and 12 months follow up

INTRODUCTION

In acute symptomatic vertebrobasilar artery stenosis, the use of mechanical recanalisation remains controversial. The complication rate of acute interventional recanalisation (aIR) has to be considered, as evidence from randomised trials is lacking. In a single centre retrospective case series, we here describe complications and outcome after aIR.

METHODS

We retrospectively assessed aIR in a tertiary care centre and included the following parameters: indication for aIR, national institute of health stroke scale (NIHSS) score on admission, recanalisation by thrombolysis in myocardial infarction score (TIMI) grades, post-interventional complications, mortality, NIHSS and modified Rankin scale at follow-up and rate of restenosis.

RESULTS

We identified 14 aIR (14 percutaneous transluminal angioplasty with or without stent implantation in 12 patients; 6/12 with thrombolysis; n = 6 vertebral artery, n = 8 basilar artery; 4 women, mean age 67 years). Mortality was 25 % (3/12) after 7 days and 42 % (5/12) after 12 months. In 12/14, interventions are complete (TIMI 3, 86 %), in 2/14, a partial recanalisation (TIMI 2, 14 %) was achieved. In one case, a peri-interventional fatal intracerebral haemorrhage occurred (1/12, 8 %). At late follow-up (mean 342 days), one re-occlusion (1/7, 14 %) and one recurrent stroke (1/12, 8 %) were observed.

CONCLUSIONS

In our single centre series of vertebrobasilar aIR recanalisation rate was high. However, procedural safety and clinical outcome varied considerably. The results of aIR need to be assessed in multicentric registers to define the procedural risk and outcome in the clinical setting.

Off-label use of drugs and devices in the neuroendovascular suite

SUMMARY

The off-label use of drugs and devices in neuroendovascular procedures is common. Neurointerventionalists should be well aware of the level of evidence available in support of the off-label use of drugs and devices in their practice and some of the potential adverse events associated with them. These uses are categorized as I or II if they have been evaluated as primary or ancillary interventions in prospective trials/registries of neuroendovascular procedures and III if they were evaluated in case series. Category IV use is based on evaluation as primary or ancillary interventions in prospective trials/registries of non-neuroendovascular procedures. Physicians are allowed to use off-label drugs and procedures if there is strong evidence that they are beneficial for the patient. The neurointerventional professional societies agree that off-label use of drugs and devices is an important part of the specialty, but practicing providers should base their decisions on sound evidence when using such drugs and devices.

Current diagnosis and management of symptomatic intracranial atherosclerotic disease

PURPOSE OF REVIEW

Intracranial atherosclerotic disease (IAD) is likely the most common cause of stroke world-wide and is associated with a very high risk of recurrence. It results in cerebral ischemia due to a variety of mechanisms, including artery-to-artery embolism, hemodynamic failure, and occlusion of penetrating arteries. New imaging modalities focused on physiological consequences of IAD have become available and recent treatment trials have been completed.

RECENT FINDINGS

We review the traditional imaging modalities, emphasizing the advantages and limitations of each method, and discuss the novel physiological approaches that interrogate physiological process to indicate specific mechanisms of ischemia. These allow deeper understanding of the pathophysiological processes that underlie IAD-related ischemia. The key findings of recent therapeutic trials are reviewed, including the landmark randomized studies showing advantage of antiplatelet agents and risk factor modification, and a significant risk of complications with endovascular approaches.

SUMMARY

Current evidence argues for aggressive medical management and suggests caution with interventional treatments. We propose that mechanistic information will further refine the risk assessment of patients with IAD to offer targeted therapy.

Treatment of intracranial atherosclerotic disease with a balloon-expandable paclitaxel eluting stent: procedural safety, efficacy and mid-term patency

Purpose

Procedural safety and high rates of in-stent recurrent stenotic lesions (ISR) remain a concern in the endovascular treatment of intracranial atherosclerotic disease (ICAD). In the present study technical feasibility, safety and efficacy of the paclitaxel eluting balloon-expandable coronary stent Coroflex^® Please was assessed in the treatment of ICAD.

Methods

A total of 95 patients (79 male; median age 68 years) with 106 intracranial atherosclerotic stenotic lesions underwent endovascular treatment using Coroflex^® Please stents (B. Braun, Melsungen, Germany). Location and degree of target stenoses before and after treatment and at follow-up and adverse clinical sequelae of treatment were registered. Post-procedural medication included 100 mg acetylsalicylic acid (ASA) and 75 mg clopidogrel for 1 year. Angiographic follow-up was scheduled for 6, 12, 26 and 52 weeks after the treatment.

Results

The lesion locations were as follows: internal carotid artery (ICA) petrous (n = 44, 42%), ICA cavernous (n = 43, 41%), ICA paraclinoid (n = 4, 4%), intradural vertebral artery (VA; n = 11, 10%) and basilar artery (BA; n = 4, 4%). Of the lesions seven could not be treated due to difficult anatomy and stent stiffness (7% technical failure rate). The combined post-interventional neurological morbidity and mortality rate, including stroke, intracerebral hemorrhage (ICH), subarachnoid hemorrhage (SAH) and carotid cavernous fistula (CCF) was n = 4 (3.7%) within and n = 1 (0.9%) at and beyond 30 days, respectively. Angiographic and clinical follow-up examinations were carried out for 78 (78%) of the lesions (mean 16.1 months, maximum 48 months). Asymptomatic recurrent stenosis was seen in 3 out of 78 (3.8%) lesions and there was 1 case of late stent thrombosis (0.9%).

Conclusions

Treatment of ICAD using drug-eluting coronary stents is safe and effective but technical failure due to stent stiffness remains a problem. Application of the more flexible, newest generation thin-strut stents, however, shows promising results.