Stenting versus medical treatment for severe symptomatic intracranial stenosis

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

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

Effect of Stenting Plus Medical Therapy vs Medical Therapy Alone on Risk of Stroke and Death in Patients With Symptomatic Intracranial Stenosis: The CASSISS Randomized Clinical Trial

Importance

Prior randomized trials have generally shown harm or no benefit of stenting added to medical therapy for patients with symptomatic severe intracranial atherosclerotic stenosis, but it remains uncertain as to whether refined patient selection and more experienced surgeons might result in improved outcomes.

Objective

To compare stenting plus medical therapy vs medical therapy alone in patients with symptomatic severe intracranial atherosclerotic stenosis.

Design, Setting, and Participants

Multicenter, open-label, randomized, outcome assessor-blinded trial conducted at 8 centers in China. A total of 380 patients with transient ischemic attack or nondisabling, nonperforator (defined as nonbrainstem or non-basal ganglia end artery) territory ischemic stroke attributed to severe intracranial stenosis (70%-99%) and beyond a duration of 3 weeks from the latest ischemic symptom onset were recruited between March 5, 2014, and November 10, 2016, and followed up for 3 years (final follow-up: November 10, 2019).

Interventions

Medical therapy plus stenting (n = 176) or medical therapy alone (n = 182). Medical therapy included dual-antiplatelet therapy for 90 days (single antiplatelet therapy thereafter) and stroke risk factor control.

Main Outcomes and Measures

The primary outcome was a composite of stroke or death within 30 days or stroke in the qualifying artery territory beyond 30 days through 1 year. There were 5 secondary outcomes, including stroke in the qualifying artery territory at 2 years and 3 years as well as mortality at 3 years.

Results

Among 380 patients who were randomized, 358 were confirmed eligible (mean age, 56.3 years; 263 male [73.5%]) and 343 (95.8%) completed the trial. For the stenting plus medical therapy group vs medical therapy alone, no significant difference was found for the primary outcome of risk of stroke or death (8.0% [14/176] vs 7.2% [13/181]; difference, 0.4% [95% CI, -5.0% to 5.9%]; hazard ratio, 1.10 [95% CI, 0.52-2.35]; P = .82). Of the 5 prespecified secondary end points, none showed a significant difference including stroke in the qualifying artery territory at 2 years (9.9% [17/171] vs 9.0% [16/178]; difference, 0.7% [95% CI, -5.4% to 6.7%]; hazard ratio, 1.10 [95% CI, 0.56-2.16]; P = .80) and 3 years (11.3% [19/168] vs 11.2% [19/170]; difference, -0.2% [95% CI, -7.0% to 6.5%]; hazard ratio, 1.00 [95% CI, 0.53-1.90]; P > .99). Mortality at 3 years was 4.4% (7/160) in the stenting plus medical therapy group vs 1.3% (2/159) in the medical therapy alone group (difference, 3.2% [95% CI, -0.5% to 6.9%]; hazard ratio, 3.75 [95% CI, 0.77-18.13]; P = .08).

Conclusions and Relevance

Among patients with transient ischemic attack or ischemic stroke due to symptomatic severe intracranial atherosclerotic stenosis, the addition of percutaneous transluminal angioplasty and stenting to medical therapy, compared with medical therapy alone, resulted in no significant difference in the risk of stroke or death within 30 days or stroke in the qualifying artery territory beyond 30 days through 1 year. The findings do not support the addition of percutaneous transluminal angioplasty and stenting to medical therapy for the treatment of patients with symptomatic severe intracranial atherosclerotic stenosis.

Trial Registration

ClinicalTrials.gov Identifier: NCT01763320.

Incidence and Risk Factors of In-Stent Restenosis for Symptomatic Intracranial Atherosclerotic Stenosis: A Systematic Review and Meta-Analysis

BACKGROUND

In-stent restenosis affects long-term outcome in patients with intracranial atherosclerotic stenosis.

PURPOSE

The aim of this meta-analysis was to evaluate the incidence and risk factors of in-stent restenosis.

DATA SOURCES

All literature that reported in-stent restenosis was searched on PubMed, Ovid EMBASE and Ovid MEDLINE data bases.

STUDY SELECTION

Original articles about stents for symptomatic intracranial atherosclerotic stenosis were selected.

DATA ANALYSIS

Meta-analysis was conducted to derive the pooled in-stent restenosis using a random-effects model. Meta-regression was performed to explore the risk factors predisposing to in-stent restenosis.

DATA SYNTHESIS

In total, 51 studies with 5043 patients were included. The pooled incidence rate of in-stent restenosis was 14.8% (95% CI, 11.9%-17.9%). Among the lesions with in-stent restenosis, 28.8% of them led to (95% CI, 22.0%-36.0%) related neurologic symptoms. The series in the United States had a higher in-stent restenosis rate (27.0%; 95% CI, 20.6%-33.9%) compared with those from Asia (13.6%; 95% CI, 10.3%-17.2%) and other regions as a whole (7.6%; 95% CI, 1.1%-18.1%) (P < .01). Multiregression analysis revealed that younger patient age was related to high in-stent restenosis rates (P = .019), and vertebrobasilar junction location (P = .010) and low residual stenosis (P = .018) were 2 independent risk factors for symptomatic in-stent restenosis rate.

LIMITATIONS

The heterogeneity of most outcomes was high.

CONCLUSIONS

Our study showed promising results of in-stent restenosis for symptomatic atherosclerotic stenosis. Studies are needed to further expatiate on the mechanisms by which younger patient age, vertebrobasilar junction location, and low residual stenosis could increase in-stent restenosis and symptomatic in-stent restenosis, respectively.

Percutaneous Transluminal Angioplasty with Stent Placement versus Best Medical Therapy Alone in Symptomatic Intracranial Arterial Stenosis: A Best Evidence Review

Intracranial arterial stenosis (ICAS) is a common cause of stroke, and the risk of ischemic stroke from a stenotic intracranial artery remains high despite best medical therapy (BMT). As a result, clinicians have increasingly turned to percutaneous transluminal angioplasty and stenting (PTAS) over the last decade as an alternative therapy in high-risk patients with symptomatic ICAS. In this review, we will critically analyze multiple clinical trials to assess the safety and efficacy of PTAS with BMT versus BMT alone. The Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis (SAMMPRIS) trial reported a higher rate of stroke or death within 30 days in the PTAS plus BMT group (14.7%) than the BMT only group (5.8%, p = 0.002). The rate of any stroke during the follow-up period (mean = 32 months) was higher in the PTAS plus BMT group (22.3%) than the BMT only group (14.1%, p = 0.03). The Vitesse Intracranial Stent Study for Ischemic Stroke Therapy (VISSIT) trial reported a higher rate of stroke or death within 30 days in the PTAS plus BMT cohort (24.1%) than the BMT only cohort (9.4%, p = 0.05). There was also a higher rate of hard transient ischemic attack (TIA) or stroke within one year in the PTAS plus BMT group (36.2%) than the BMT only group (15.1%, p = 0.02). The Vertebral Artery Ischaemia Stenting (VIST) trial reported the rate of any stroke during the follow-up period to be two events in 50 person-years in the PTAS plus BMT cohort versus four events in 45 person-years in the BMT only cohort, with a calculated hazard ratio of 0.47 (p = 0.39). Vertebral Artery Stenting Trial (VAST) reported a higher incidence of stroke, MI, or vascular death in the PTAS with BMT cohort (22%) than the BMT only cohort (0%). Tang et al. reported no significant difference in the incidence of vascular events at one year and three years between the PTAS plus BMT and BMT only cohorts. However, the distribution of vascular events was more concentrated in the first postoperative week in the PTAS plus BMT cohort (75% of all vascular events) versus the BMT only cohort (17%). Feng et al. reported a lower periprocedural complication rate (9.1%) with the Enterprise stent in comparison to the Wingspan and balloon-expandable stents used in the SAMMPRIS and VISSIT trials. We conclude that PTAS should not be employed as first-line treatment in patients with symptomatic ICAS. However, PTAS should be considered in symptomatic ICAS patients that are hemodynamically unstable or have repeatedly failed BMT, especially at sites with lower rates of perioperative complications than those reported here.

Seven years' follow-up of comparative study between stenting and medication for treatment of symptomatic vertebrobasilar artery stenosis

Objective Endovascular stent-assistant angioplasty (ESAA) is a valid treatment for symptomatic vertebrobasilar artery stenosis (SVAS), but the long-term effect and the improvement of condition compared with medication treatment are unknown. This study investigated the long-term efficacy of ESAA in patients with moderate and severe SVAS, and compared the efficacy with medication treatment. Materials and methods We conducted a retrospective analysis of clinical data of 43 patients with moderate and severe SVAS hospitalized in our department. According to different treatment methods they were divided into 29 cases in an ESAA group and 14 cases in a medication treatment group. During the follow-up period, the degree of vascular stenosis, vascular blood flow velocity, restenosis rate, recovery of neurological function and the incidence of cerebral ischemic events in the two groups were analyzed. Results The average clinical follow-up period was 89.4 ± 10.2 months. Before treatment, the stenosis rate and average blood flow velocity of the two groups were not statistically significant ( p > 0.05). During the follow-up period, both were significantly lower than the medication treatment group ( p < 0.01). In the ESAA group, three cases of stent stenosis, and three cases in the medication treatment group were completely occluded. The total ischemic events in ESAA group were three cases, compared with nine cases in the medication treatment group; the difference was statistically significant ( p < 0.05). Conclusion ESAA has a long-term effect in the treatment of symptomatic moderate and severe vertebrobasilar artery stenosis. It is superior to medication therapy in preventing posterior circulation ischemia (PCI), but a larger sample size is still needed to confirm the study.

Comparison of stent versus medical therapy for symptomatic patients with intracranial atherosclerotic stenosis: A meta-analysis

PURPOSE

To compare the outcomes of intracranial stent implantation and medical therapy for treatment of severe intracranial stenosis.

METHODS

Articles were identified from Medline, Cochrane, EMBASE, and Google Scholar published up to August 25, 2016. Eligible studies reported stroke occurrence, transient ischemic attack (TIA), and event-free survival rates in patients who suffered recent TIA or stroke caused by stenosis of a major intracranial artery and treated with either medical therapy or stenting. 4 studies enrolled a total 739 patients.

RESULTS

While no association between intracranial endovascular therapy and short-term stroke risk was found (pooled OR=1.349, 95% CI=0.541 to 3.367, P=0.521), significantly higher rate of stroke occurrence was observed in patients treated with stent therapy within 30days of treatment (pooled OR=3.143, 95% CI=1.755 to 5.628, P<0.001). No association was found between the type of treatment and TIA occurrence (pooled OR=0.702, 95% CI=0.277 to 1.781, P=0.457) and event-free survival rate (pooled HR=1.170, 95% CI=0.947 to 1.447, P=0.145).

CONCLUSION

Patients with symptomatic intracranial atherosclerotic stenosis undergoing stent therapy may have higher risk of short-term stroke.

Reproducibility of Middle Cerebral Artery Stenosis Measurements by DSA: Comparison of the NASCET and WASID Methods

Purpose

To evaluate the intra- and inter-observer variability of the North American Symptomatic Carotid Endarterectomy Trial (NASCET) and Warfarin-Aspirin Symptomatic Intracranial Disease (WASID) criteria for the evaluation of middle cerebral artery (MCA) stenosis using digital subtraction angiography (DSA).

Materials and Methods

DSA images of 114 cases with 131 stenotic MCAs were retrospectively analyzed. Two radiologists and a researcher measured the degree of MCA stenosis independently using both NASCET and WASID methods. To determine intra-observer agreement, all the observers reevaluated the degree of MCA stenosis 4 weeks later. The linear relation and coefficient of variation (CV) between the measurements made by the two methods were assessed by correlation coefficient and multi-factor analysis of variance (ANOVA), respectively. Intra- and inter-observer variability of the two methods was evaluated by intraclass correlation coefficient (ICC), Spearman’s R value, Pearson correlation coefficient and Bland-Altman plots.

Results

Despite the fact that the degree of MCA stenosis measured by NASCET was lower than measured using the WASID method, there was good linear correlation between the measurements made by the two methods (for the mean measurements of the 3 observers, NASCET% = 0.891 × WASID% - 1.89%; ICC, Spearman’s R value and Pearson correlation were 0.874, 0.855, and 0.874, respectively). The CVs of both intra- and inter-observer measurements of MCA stenosis using WASID were significantly lower than that using NASCET confirmed by the multi-factor ANOVA results, which showed only the measurement methods of MCA stenosis had significant effects on the CVs both in intra- and inter-observer measurements (both P values < 0.001). Intra-observer measurements showed good or excellent agreement with respect to WASID and NASCET evaluation (ICC, 0.656 to 0.817 and 0.635 to 0.761, respectively). Good agreement for the WASID evaluation (ICC, 0.592 to 0.628) and for the NASCET evaluation (ICC, 0.529 to 0.568) was observed for inter-observer measurements. Bland-Altman plots demonstrated that the WASID method had better reproducibility and intra-observer agreement than NASCET method for evaluating MCA stenosis.

Conclusion

Both NASCET and WASID methods have an acceptable level of agreement; however, the WASID method had better reproducibility for the evaluation of MCA stenosis, and thus the WASID method may serve as a standard for measuring the degree of MCA stenosis.

Comparison of high-resolution MRI with CT angiography and digital subtraction angiography for the evaluation of middle cerebral artery atherosclerotic steno-occlusive disease

Intracranial atherosclerotic disease is increasingly recognized as a major stroke subtype worldwide. Current diagnostic evaluation of atherosclerotic disease of the middle cerebral artery (MCA) relies on detection of stenoses with luminographic imaging studies that do not directly visualize plaque unlike high-resolution MRI. This retrospective study seeks to evaluate the accuracy of high-resolution MRI vessel wall imaging, computed tomographic angiography (CTA) and digital subtraction angiography (DSA) in measuring the degree of stenosis within the MCA. 28 recently symptomatic patients with MCA territory symptoms underwent preliminary imaging with CTA followed by high-resolution MRI at 3-Tesla and definitive imaging with DSA for detection of M1 territory steno-occlusive lesions. Measurements of MCA segments on MRI and CTA were compared with reference to DSA values. Sensitivity and specificity of high-resolution MRI vessel wall imaging, CTA using maximum intensity projection (MIP) and CTA using volume rendering (VR) for the detection of stenosis > 50 % and occlusion were 80.0 and 53.6 %, 72.2 and 72.7 %, and 77.8 and 18.2 %, respectively. MRI-derived values correlated better with DSA (Spearman R = 0.68, p < 0.01) than CTA MIP and VR (Spearman R = 0.45, 0.22; p = 0.02, 0.24, respectively). High-resolution MRI of the MCA is capable of accurately measuring the degree of stenosis and is more sensitive than CTA in a sample of high-risk, symptomatic patients. This study, combined with previous reports, supports the potential of morphological MRI to measure intracranial atherosclerotic plaque non-invasively.

Intracranial atheromatous disease treatment with the Wingspan stent system: evaluation of clinical, procedural outcome and restenosis rate in a single-center series of 21 consecutive patients with acute and mid-term results

BACKGROUND

Intracranial atherosclerosis may be the underlying pathology in up to 15% of ischemic strokes, but may account for about 40% of strokes in some populations. After an ischemic event determined by intracranial atherosclerosis, patients have a 12% annual risk of stroke recurrence, mostly during the first year.

OBJECTIVE

To evaluate procedural safety, clinical outcome and restenosis rate of Wingspan stent placement.

METHODS

Twenty-one caucasoid patients were enrolled. Target patients were affected by high-grade, symptomatic, intracranial atherosclerotic lesions, were on antithrombotic therapy and at high stroke risk. All patients were treated with the Wingspan stent system.

RESULTS

Technical success resulted 100%, with all target lesions being reduced to <50%. No stroke or death were observed at 30. The mean percent of stenosis was reduced from a middle value of 84% to a middle value of 17% after stent placement. Medium follow-up was 19.5months (range 6-36months). No stroke or death occurred in any patient. None of the patients presented a <50% stent patency rate at follow-up.

CONCLUSIONS

The short-term results and follow up analysis provide evidence demonstrating the safety of the Wingspan system when used in high-risk patient population. Due to concerns regarding long-term stent patency and ischemic events occurrence emerged from clinical trials such as the SAMMPRIS, intracranial angioplasty and stent with the Wingspan system should be considered only for high risk patients in which it may be considered the only viable therapeutic option.

Wingspan experience in the treatment of symptomatic intracranial atherosclerotic disease after antithrombotic failure

BACKGROUND AND PURPOSE

Intracranial stenting with the Wingspan system has been used as a revascularization strategy in symptomatic patients with intracranial atherosclerotic disease (ICAD). The latest results of the Stenting versus Aggressive Medical Therapy for Intracranial Artery Stenosis (SAMMPRIS) trial challenge this approach. Our experience in the treatment of symptomatic ICAD with the Wingspan system is reported.

MATERIALS AND METHODS

Patients who underwent stenting for symptomatic ICAD were included in the analysis. Demographic data, periprocedural complications, long term radiological and clinical outcomes are reported.

RESULTS

46 lesions were treated in 45 patients. 13 patients (29%) presented with a transient ischemic attack and 32 (71%) with a stroke. 43 patients (95.5%) failed antithrombotic therapy at presentation. One (2%) symptomatic periprocedural (24 h) complication occurred. The 30 day incidence of stroke and vascular death was 6.6%--a fatal hemorrhagic stroke and two non-fatal hemorrhagic strokes. In-stent stenosis (≥50%) was seen in nine (42.8%) lesions, two were symptomatic.

CONCLUSIONS

This cohort of patients with symptomatic ICAD who failed antithrombotic medications benefited from angioplasty and stenting with the Wingspan system.

Comparison of NASCET and WASID criteria for the measurement of intracranial stenosis using digital subtraction and computed tomography angiography of the middle cerebral artery

BACKGROUND AND PURPOSE

Intracranial large-artery atherosclerosis is considered a frequent cause of stroke worldwide, particularly in Asian populations. The current evidence suggests that symptomatic patients with severe stenosis may benefit from intracranial stents. There are two methods for calculating the degree of intracranial stenosis, Warfarin-Aspirin Symptomatic Intracranial Disease (WASID) and North American Symptomatic Carotid Endarterectomy Trial (NASCET), but they have never been compared.

METHODS

A total of 25 patients with suspected middle cerebral artery (MCA) stenosis based on their acute presentation were imaged by computed tomography angiography (CTA), then confirmed by digital subtraction angiography (DSA). Measurements were carried out on symptomatic MCA using both methods for determining the degree of stenosis.

RESULTS

The degree of stenosis was significantly different using NASCET and WASID methods in DSA (48.2% vs. 54.6%; P<0.01), whereas CTA values did not differ significantly (54.2% vs. 52.0%; P = 0.9). All measurements were highly correlated between methods (Spearman r = 0.92 and 0.89, respectively; P<0.01).

CONCLUSION

The results of this study suggest that NASCET and WASID measures are, on average, generally similar, although substantial disagreement in a given patient may be seen.