Cerebral collateral circulation as an independent predictor for in-stent restenosis after carotid artery stenting.

Background: In-stent restenosis is a crucial problem after carotid artery stenting, but the exact predictors of in-stent restenosis remain unclear. We aimed to evaluate the effect of cerebral collateral circulation on in-stent restenosis after carotid artery stenting and to establish a clinical prediction model for in-stent restenosis. Methods: This retrospective case-control study enrolled 296 patients with severe carotid artery stenosis of C1 segment (≥70%) who underwent stent therapy from June 2015 to December 2018. Based on follow-up data, the patients were divided into the in-stent restenosis and no in-stent restenosis groups. The collateral circulation of the brain was graded according to the criteria of the American Society for Interventional and Therapy Neuroradiology/Society for Interventional Radiology (ASITN/SIR). Clinical data were collected, such as age, sex, traditional vascular risk factors, blood cell count, high-sensitivity C-reactive protein, uric acid, stenosis degree before stenting and residual stenosis rate, and medication after stenting. Binary logistic regression analysis was performed to identify potential predictors of in-stent restenosis, and a clinical prediction model for in-stent restenosis after carotid artery stenting was established. Results: Binary logistic regression analysis showed that poor collateral circulation was an independent predictor of in-stent restenosis (P=0.003). We also found that a 1% increase in residual stenosis rate was associated with a 9% increase in the risk of in-stent restenosis (P=0.02). Ischemic stroke history (P=0.03), family history of ischemic stroke (P<0.001), in-stent restenosis history (P<0.001), and nonstandard medication after stenting (P=0.04) were predictors of in-stent restenosis. The risk of in-stent restenosis was lowest when the residual stenosis rate was 12.5% after carotid artery stenting. Furthermore, we used some significant parameters to construct a binary logistic regression prediction model for in-stent restenosis after carotid artery stenting in the form of a nomogram. Conclusions: Collateral circulation is an independent predictor of in-stent restenosis after successful carotid artery stenting, and the residual stenosis rate tends to be below 12.5% to reduce restenosis risk. The standard medication should be strictly carried out for patients after stenting to prevent in-stent restenosis.

Use of covered stents to treat complex cerebrovascular diseases: Expert consensus.

The treatment of complex cerebrovascular diseases (CCVDs) at the skull base, such as complex intracranial aneurysms, carotid-cavernous sinus fistulas, and intracranial artery traumatic injuries, is a difficult clinical problem despite advances in endovascular and surgical therapies. Covered stents or stent graft insertion is a new concept for endovascular treatment that focuses on arterial wall defect reconstruction, differing from endovascular lesion embolization or flow diverter therapies. In recent years, covered stents specifically designed for cerebrovascular treatment have been applied in the clinical setting, allowing thousands of patients with CCVDs to undergo intraluminal reconstruction treatment and achieving positive results, even in the era of flow diverters. Since there is no unified reference standard for the application of covered stents for treating CCVDs, it is necessary to further standardize and guide the clinical application of this technique. Thus, we organized authoritative experts in the field of neurointervention in China to write an expert consensus, which aims to summarize the results of covered stent insertion in the treatment of CCVDs and propose suitable standards for its application in the clinical setting. Based on the contents of this consensus, clinicians can use individualized intraluminal reconstruction treatment techniques for patients with CCVDs.

Effect of intracranial venous collaterals on neurological outcomes in cerebral venous thrombosis.

This study identifies predictors of favourable intracranial venous collaterals and the effect of intracranial venous collaterals on outcomes and recanalization in patients with cerebral venous thrombosis (CVT). Data of 61 patients with CVT were retrospectively reviewed. Venous collateralization was defined as expanded cortical vein formation through different drainage pathways. Recanalization grades were classified into complete or partial recanalization based on images obtained during hospitalisation and follow-up. Independent predictors of collateral formation and poor prognosis were investigated via univariate and binary logistic regression analyses. The effects of different intracranial venous collaterals on recanalization in patients with CVT were assessed. A risk prediction nomogram for prognosis was constructed. Age ≤ 35 years (odds ratio (OR) = 7.067; 95% confidence interval (CI) = 1.776-28.277; P = 0.006) and male sex (OR = 5.490; 95% CI = 1.205-25.004; P = 0.028) were independent predictors of favourable venous collaterals. Venous collaterals were associated with early recanalization (P = 0.017) and not with long-term recanalization (P = 0.252). Male sex (OR = 0.047; 95% CI = 0.003-0.651; P = 0.023), subacute onset (OR = 0.026; 95% CI = 0.002-0.367; P = 0.007), and good collateral grade (OR = 0.168; 95% CI = 0.029-0.985; P = 0.048) were independent factors of favourable neurological outcomes at discharge. Haemorrhage on computed tomography at admission (OR = 10.868; 95% CI = 2.082-56.733; P = 0.005) was inversely correlated with prognosis. These findings suggested that male patients under 35 years of age are more likely to have favourable venous collaterals and good outcomes. Venous collaterals are significantly associated with early recanalization. These findings highlight the importance of venous collateral evaluation in patients with CVT.

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.