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

The Efficacy and Safety of Endovascular Treatment on Large Vessel Occlusion of Intracranial Atherosclerosis Versus Embolism: A Meta-Analysis

This study is to assess the efficacy and safety of endovascular treatment for acute ischemic stroke resulting from intracranial atherosclerosis-large vessel occlusion (ICAS-LVO) in comparison to embolic-large vessel occlusion (embolic-LVO). We undertook an extensive search of databases including PubMed, Embase, The Cochrane Library, Wanfang Data, and China National Knowledge Internet using a combination of free-text terms and mesh terms as part of our search strategy. Literature screening and data retrieval were conducted following predefined inclusion/exclusion criteria. The search timeframe was limited to studies published until August 2021. All statistical evaluations were carried out by Review Manager 5.3. This meta-analysis comprised a total of 2748 patients across 14 studies. Our results demonstrate a significantly lower rate of systematic intracranial hemorrhage in ICAS-LVO compared with embolic-LVO following endovascular therapy. Moreover, the rates of rescue therapy and stent implantation were significantly lower in ICAS-LVO versus embolic-LVO. However, the 2 groups had a similar recanalization rate, favorable outcome, and mortality rates at 90 days post endovascular treatment. Patients with ICAS-LVO exhibit a lower incidence of systematic intracranial hemorrhage after treatment compared with those with embolic-LVO. Furthermore, ICAS-LVO patients did not demonstrate a unique risk profile regarding recanalization, favorable outcomes (at 90 days), and mortality (at 90 days), resulting in comparable outcomes to embolic-LVO. However, a higher proportion of stent implantation and rescue therapy was observed in ICAS-LVO patients, highlighting the need for further investigation into the standardization of endovascular management for ICAS-LVO.

Exosomes of endothelial progenitor cells repair injured vascular endothelial cells through the Bcl2/Bax/Caspase-3 pathway

The main objective of this study is to evaluate the influence of exosomes derived from endothelial progenitor cells (EPC-Exo) on neointimal formation induced by balloon injury in rats. Furthermore, the study aims to investigate the potential of EPC-Exo to promote proliferation, migration, and anti-apoptotic effects of vascular endothelial cells (VECs) in vitro. The underlying mechanisms responsible for these observed effects will also be thoroughly explored and analyzed. Endothelial progenitor cells (EPCs) was isolated aseptically from Sprague-Dawley (SD) rats and cultured in complete medium. The cells were then identified using immunofluorescence and flow cytometry. The EPC-Exo were isolated and confirmed the identities by western-blot, transmission electron microscope, and nanoparticle analysis. The effects of EPC-Exo on the rat carotid artery balloon injury (BI) were detected by hematoxylin and eosin (H&E) staining, ELISA, immunohistochemistry, immunofluorescence, western-blot and qPCR. LPS was used to establish an oxidative damage model of VECs. The mechanism of EPC-Exo repairing injured vascular endothelial cells was detected by measuring the proliferation, migration, and tube function of VECs, actin cytoskeleton staining, TUNEL staining, immunofluorescence, western-blot and qPCR. In vivo, EPC-Exo exhibit inhibitory effects on neointima formation following carotid artery injury and reduce the levels of inflammatory factors, including TNF-α and IL-6. Additionally, EPC-Exo downregulate the expression of adhesion molecules on the injured vascular wall. Notably, EPC-Exo can adhere to the injured vascular area, promoting enhanced endothelial function and inhibiting vascular endothelial hyperplasia Moreover, they regulate the expression of proteins and genes associated with apoptosis, including B-cell lymphoma-2 (Bcl2), Bcl2-associated x (Bax), and Caspase-3. In vitro, experiments further confirmed that EPC-Exo treatment significantly enhances the proliferation, migration, and tube formation of VECs. Furthermore, EPC-Exo effectively attenuate lipopolysaccharides (LPS)-induced apoptosis of VECs and regulate the Bcl2/Bax/Caspase-3 signaling pathway. This study demonstrates that exosomes derived from EPCs have the ability to inhibit excessive carotid intimal hyperplasia after BI, promote the repair of endothelial cells in the area of intimal injury, and enhance endothelial function. The underlying mechanism involves the suppression of inflammation and anti-apoptotic effects. The fundamental mechanism for this anti-apoptotic effect involves the regulation of the Bcl2/Bax/Caspase-3 signaling pathway.

Sub-satisfactory recanalization of severe middle cerebral artery stenoses can significantly improve hemodynamics

Purpose

To investigate the effect of sub-satisfactory stent recanalization on hemodynamic stresses for severe stenoses of the middle cerebral artery (MCA) M 1 segment.

Materials and methods

Patients with severe stenoses of the MCA M1 segment treated with endovascular stent angioplasty were retrospectively enrolled. Three-dimensional digital subtraction angiography before and after stenting was performed; the computational fluid dynamics (CFD) analysis of hemodynamic stresses at the stenosis and normal segments proximal and distal to the stenoses was analyzed.

Results

Fifty-one patients with severe stenosis at the MCA M1 segment were enrolled, with the stenosis length ranging from 5.1 to 12.8 mm (mean 9 ± 3.3 mm). Stent angioplasty was successful in all (100%) the patients. The angiography immediately after stenting demonstrated a significant (P < 0.05) decrease in MCA stenosis after comparison with before stenting (31.4 ±12.5% vs. 87.5 ± 9.6%), with residual stenosis of 15–30% (mean 22.4 ± 3.5%). Before stenting, the total pressure was significantly higher (P < 0.0001), while the WSS, velocity, and vorticity were all significantly decreased (P < 0.0001) at the normal arterial segment proximal to the stenosis, and the total pressure, WSS, velocity, and vorticity were all significantly decreased (P < 0.0001) at the normal arterial segment distal to the stenosis compared with those at the stenosis. After sub-satisfactory stenting recanalization, all the hemodynamic stresses proximal or distal to the stenosis and at the perforator root were improved compared with those before stenting and were similar to those after virtual stenosis removal.

Conclusion

Sub-satisfactory recanalization of severe MCA stenoses can significantly improve the hemodynamic status for cerebral perfusion at the stenoses.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Outcome of Wingspan Stent Using Aggressive Post-stent Balloon Dilation for Intracranial Atherosclerosis Stenosis

Background: Wingspan stent has gained interest for better long-term outcomes for intracranial atherosclerosis disease (ICAD). However, in-stent restenosis still presents as a problem and may cause postoperative neurological events. We aimed to find a way to prevent in-stent restenosis.

Method: Patients with stenosis >70% ICAD were treated with wingspan stent and were retrospectively reviewed. The patients were separated into two groups: one with post-dilation and the other without post-dilation. The outcomes of wingspan stenting were compared immediately after the surgery and at a 1-year follow-up.

Results: Overall, 28 patients were included for analysis, with 15 patients undergoing post-dilation and 13 patients not undergoing the procedure. The extent of stenosis was significantly lower in the post-dilation group than in the no post-dilation group, both immediately after the surgery (14.8 ± 10.2 vs. 28.5 ± 14.5%, p < 0.01) and at 1-year follow-up (25.8 ± 18.0 vs. 50.1 ± 23.2%, p < 0.01). The post-dilation method immediately expanded the stent diameter (2.89 ± 0.48 vs. 3.05 ± 0.44 mm, p < 0.001), and the diameter still increased at 1-year follow-up (3.05 ± 0.44 vs. 3.12 ± 0.43 mm, p < 0.01) due to the self-expandable property of the wingspan. Similarly, in the no post-dilation group, the stent size was also increased (2.70 ± 0.67 vs. 2.80 ± 0.64 mm, p < 0.01). However, at 1-year follow up, the luminal diameter was stationary in the post-dilation group (2.36 ± 0.73 vs. 2.46 ± 0.82 mm, p = 0.88) and decreased in the no post-dilation group (2.24 ± 0.56 vs. 1.60 ± 0.79 mm, p < 0.01). The periprocedural complication rate was similar between the groups.

Conclusion: The post-dilation method can be feasibly performed and can offer better stent expansion and apposition in the wingspan system. By applying this technique, we might prevent in-stent restenosis and improve neurological outcomes.

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.

Factors affecting in-stent restenosis after angioplasty with the Enterprise stent for intracranial atherosclerotic diseases

This study investigated factors affecting the safety and in-stent restenosis after intracranial stent angioplasty using the Enterprise stent for symptomatic intracranial atherosclerotic stenosis. Between January 2017 and March 2019, patients with intracranial atherosclerotic stenosis treated with Enterprise stent angioplasty were enrolled, including 400 patients in the modeling group and 89 patients in the validation group. The clinical factors affecting in-stent restenosis after Enterprise stent angioplasty in the modeling group were analyzed, and a logistic regression model of these factors was established and validated in the validation group. The receiver operating characteristic (ROC) curve and the area under the ROC curve (AUC) were analyzed. In the modeling group with 400 patients, there were 410 lesions, including 360 stenotic lesions and 50 occluded lesions, with 176 (42.9%) lesions in the anterior circulation and 234 (57.1%) in the posterior circulation. Successful stenting was performed in 398 patients (99.5%). Stenosis was significantly (P < 0.05) improved after stenting compared with before stenting (27.7% ± 2.9% vs. 77.9% ± 8.0%). Periprocedural complications included ischemic stroke (3.25%), hemorrhagic stroke (0.75%), and death (0.50%), with a total periprocedural complication rate of 4.0%. The first follow-up angiography was performed in 348 (87.0%) patients with 359 lesions 3.5-14 months (mean 5.7 months) after stenting. In-stent restenosis occurred in 62 (17.3%) lesions, while the other 295 (82.7%) had no restenosis. Lesion location, calcification degree, balloon expansion pressure, residual stenosis, intraprocedural dissection, and cerebral blood flow TICI grade were significant (P < 0.05) risk factors for in-stent restenosis. The in-stent restenosis prediction model was established as follows: P = 1/[1 + e^{-(-6.070-1.391 location + 2.745 calcification + 4.117 balloon inflation pressure + 2.195 intraprocedural dissection + 1.163 residual stenosis + 1.174 flow TC grade)}]. In the validation group, the AUC in the ROC curve analysis was 0.902 (95% CI: 0.836-0.969), and when the cutoff value was 0.50, the sensitivity and specificity of this model were shown to be 76.92% and 80.26%, respectively, in predicting in-stent restenosis at angiographic follow-up, with a total coincidence rate of 79.78%. In conclusion, in-stent restenosis after intracranial Enterprise stenting is affected by stenosis location, calcification, balloon inflation pressure, intraprocedural arterial dissection, residual stenosis, and cerebral flow grade, and establishment of a logistic model with these factors can effectively predict in-stent restenosis.

Stenting for Symptomatic Intracranial Vertebrobasilar Artery Stenosis in Northeast of China: A Single-Center Study

Objective: We described the incidence of surgery-related complications to evaluate the safety of endovascular therapy for severe symptomatic intracranial vertebral basilar artery stenosis (IVBS) in our stroke center in Northeast of China.

Methods: Consecutive patients with symptomatic IVBS caused by 70–99% stenosis despite standard medical treatment of antiplatelet agents plus statin were enrolled. Either balloon-mounted stent or balloon predilation plus self-expanding stent was performed. Clinical adverse events such as stroke, transient ischemic attack (TIA), and death after the surgery were documented. Radiological events such as in-stent thrombosis, dissection, and guide-wire perforation during the process were recorded as complications as well. The baseline characteristics and outcomes of patients among different Mori types were compared.

Results: From January 2017 to December 2018, 97 patients with stroke or TIA due to intracranial IVBS were treated by stenting, including 30 patients with basilar artery (BA) stenosis, 55 patients with intracranial vertebral artery (V4) stenosis, and 12 patients with V4-BA stenosis. The primary events include two intracranial hemorrhage (2.1%, 2/97), seven ischemic events (7.2%, 7/97), and two death (2.1%, 2/97). The successful stent deployment rate was 98.9% (96/97). The Apollo stents were used more for Mori A lesions. Self-expanding stents were more used in Mori C lesions. Mori C lesions were more vulnerable to endovascular procedure and showed higher rate of complications than A (p = 0.008) and B type (p = 0.047).

Conclusion: A high technical success rate of IVBS stenting could be achieved, and the safety was acceptable, whereas Mori C lesions were more vulnerable to endovascular procedure and showed a higher rate of complications than A and B types.

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.

Tandem Short-length Multi-stent Construct for Emergent Revascularization of Occlusive Long-segment Left Middle Cerebral Artery In-stent Stenosis

Endovascular stenting and balloon angioplasty is a feasible although controversial option for intracranial atherosclerotic stenosis refractory to maximize medical management. High rates of symptomatic in-stent restenosis (ISR) have been identified with Wingspan stent (Stryker, Fremont, CA, USA) placement. Revascularization of ISR by way of re-stenting is often attempted, albeit with high risk and low durability. In lesions with long-segment non-focal critical or emergent occluded stenosis, re-stenting with a single balloon mounted stent is not possible due to deliverability of a lengthy device through a tortuous carotid siphon. Tandem drug-eluting stent placement within the middle cerebral artery to address acute, occlusive ISR using a Wingspan stent, with additional stent reconstruction, has not been previously described.

Endovascular Treatment of Acute Ischemic Stroke Due to Intracranial Atherosclerotic Large Vessel Occlusion : A Systematic Review

OBJECTIVE

To evaluate the efficacy and safety of endovascular treatment (ET) of acute ischemic stroke (AIS) caused by intracranial atherosclerotic large vessel occlusion (ICAS-LVO).

METHODS

A systemic review and meta-analysis were conducted on studies published between July 2005 and October 2018 on the outcomes of ET in patients with AIS due to ICAS-LVO. The outcomes of the ICAS-LVO and embolic LVO groups were also compared.

RESULTS

A total of 17 studies including 1315 subjects with ICAS-LVO were included. In the single-arm meta-analysis, the pooled estimates of successful recanalization rate, favorable outcomes, symptomatic intracranial hemorrhage and mortality were 88% (95% CI (95% confidence interval), 84-92%), 52% (95% CI, 47-56%), 5% (95% CI, 3-7%) and 15% (95% CI, 12-19%) respectively. The preferred primary treatment was stent-retriever thrombectomy (84.1%) and the preferred rescue treatment was stent implantation with or without percutaneous transluminal angioplasty (PTA, 32.7%). In the double-arm meta-analysis, the incidence of symptomatic intracranial hemorrhage was lower in the ICAS-LVO compared to the embolic-LVO group (OR (odds ratio) = 0.60, 95% CI, 0.46-0.77, p < 0.01), whereas the implementation of rescue treatment (OR = 5.94, 95% CI, 3.15-11.19, p < 0.01) and stenting rate (OR = 10.06, 95%CI, 4.43-22.85, p < 0.01) were higher in the ICAS-LVO group. Other parameters were similar in both groups.

CONCLUSION

The use of ET is a safe and effective therapeutic option for AIS due to ICAS-LVO. Stent-retriever thrombectomy and stent-implement are the preferred primary and rescue therapies respectively for ICAS-LVO. Less symptomatic intracranial hemorrhage and higher stenting were observed in the ICAS-LVO compared to the embolic-LVO group.