Real-world Experience of Carotid Artery Stenting in Japan: Analysis of 8458 Cases from the JR-NET3 Nationwide Retrospective Multi-center Registries

Optimal Duration of Dual Antiplatelet Therapy After Carotid Artery Stenting: A Nationwide Cohort Study

BACKGROUND

Carotid artery stenting (CAS) is an alternative treatment for patients with carotid artery stenosis who are not eligible for carotid endarterectomy. Dual antiplatelet therapy (DAPT) after CAS aims to prevent ischemic stroke. However, its optimal duration remains unclear. We aimed to determine the optimal duration of DAPT by identifying the differences in clinical events that occur depending on the DAPT maintenance period.

METHODS

Data were obtained from the nationwide database of the Korean Health Insurance Review and Assessment Service between 2007 and 2019. Patients who received CAS, as identified by procedure codes, were divided into 2 groups according to the duration of DAPT (aspirin and clopidogrel): those who maintained DAPT for at least 90 days but for <6 months (short-DAPT group) and those who maintained it for longer (long-DAPT group). The primary outcome was a composite of ischemic stroke, gastrointestinal bleeding, and intracranial hemorrhage within 12 months of switching to single antiplatelet therapy. Statistical analyses used inverse probability of treatment weighting to balance baseline characteristics, with Cox regression and Fine and Gray competing risk models used to assess outcomes.

RESULTS

Of the 12 034 patients who underwent CAS, 2529 and 9505 were assigned to the short-DAPT and long-DAPT groups, respectively. In the short-DAPT group, ischemic stroke, gastrointestinal bleeding, and intracranial hemorrhage occurred in 41 (1.6%), 22 (0.9%), and 4 (0.2%) patients, respectively. In the long-DAPT group, ischemic stroke, gastrointestinal bleeding, and intracranial hemorrhage occurred in 108 (1.1%), 87 (0.9%), and 4 (0.04%) patients, respectively. The primary outcome did not differ significantly between the groups (2.5% versus 2.1%; adjusted hazard ratio of long-DAPT to short-DAPT, 0.869 [95% CI, 0.652-1.158]; P=0.337).

CONCLUSIONS

Short-duration DAPT can be recommended, as it does not differ from long-duration DAPT in terms of clinical efficacy and adverse events after CAS.

Clinical Outcomes of Carotid Artery Stenting for Carotid Artery Stenosis in Maintenance Hemodialysis Patients

Most previous large studies of carotid artery stenting (CAS) in maintenance hemodialysis patients are old-era, do not describe the types of stents and method of protection, and their effectiveness is unknown. CAS has progressed remarkably, and tailor-made CAS is now possible in hemodialysis patients according to the lesion. We aimed to analyze the outcomes of CAS in maintenance hemodialysis patients treated in our institution.We retrospectively investigated the data of patients who underwent elective CAS in our institution between January 2012 and April 2023. Firstly, we verified the outcomes of CAS in maintenance hemodialysis patients. Secondly, the outcomes of CAS in maintenance hemodialysis patients were compared with CAS in nondialysis patients during the same period.During the study period, 212 patients with carotid stenosis underwent CAS. Among these, 18 patients undergoing maintenance hemodialysis were identified for analysis. All 18 patients underwent lesion-specific tailor-made CAS. All 18 patients were technically successfully stented with good vasodilation and improvement in stenosis. No symptomatic cerebral infarction occurred within 30 days after CAS. There was no difference between dialysis and nondialysis patients in the risk of symptomatic complications and death occurring within 30 days after surgery. There was a higher risk of hemorrhagic complications not associated with prognosis in the dialysis group (23.1% vs 1.0%, P = 0.0047). No in-stent restenosis (>50% stenosis) and ipsilateral cerebral infarction at 1 year occurred during follow-up.CAS in hemodialysis patients may be safe and effective.

Randomized Controlled Trial of Cilostazol Addition for In-Stent Restenosis After Carotid Artery Stenting

BACKGROUND

Restenosis after carotid artery stenting (CAS) is associated with the risk of developing ischemic stroke. We aimed to evaluate the inhibitory effect of cilostazol addition on in-stent restenosis (ISR) in patients treated with CAS.

METHODS

In a randomized, open-label, blind-end point trial, patients with symptomatic and asymptomatic carotid artery stenosis and scheduled for CAS were randomly assigned to adding cilostazol (50 or 100 mg, twice per day) on other antiplatelets from 3 days before CAS or not adding cilostazol. Concomitant use of other antiplatelets was unrestricted. ISR was diagnosed by a peak systolic velocity of at least 1.75 m/s on duplex ultrasonography. The primary outcome was incidence of ISR within 2 years after CAS. Secondary outcomes included occurrences of cardiovascular events or any death and hemorrhagic events.

RESULTS

Participants were recruited from December 2010 to September 2015. Although the sample size was initially set to be 900 (450 in each group), 631 patients (mean age 69.9 years, 558 men, 325 in the cilostazol, and 306 in the noncilostazol group) were included in the primary analysis. Within 2 years' follow-up, ISR occurred in 31 of 325 patients (cumulative incidence 10.8%) in the cilostazol group and 46 of 306 patients (19.6%) in the noncilostazol group (hazard ratio, 0.64 [95% CI, 0.41-1.0]; P=0.056). In the exploratory analysis, incidence of ISR beyond 30 days after CAS was lower in the cilostazol group than in the noncilostazol group (10.3% versus 19.3%; P=0.040). Incidences of cardiovascular events or any death and hemorrhagic events were similar between the groups (6.2% versus 6.7% and 2.3% versus 1.4%, respectively).

CONCLUSIONS

The addition of cilostazol to other antiplatelet agents could contribute to the reduction of ISR in the chronic stage of patients who underwent CAS, the authenticity of which depends on further studies with sufficient statistical power.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT01261234.

Transradial artery access for carotid artery stenting: A pooled analysis

INTRODUCTION

Carotid artery stenting (CAS) through transradial access (TRA) is emerging as an alternative to carotid endarterectomy. However, the current evidence base is limited, mainly comprising single-center studies.

OBJECTIVE

This systematic review and meta-analysis aim to assess the safety and effectiveness of TRA for CAS, providing evidence to support clinical decisions.

METHODS

We conducted searches on PUBMED, Cochrane Library, Embase, and Web of Science databases, including studies on TRA for CAS. Studies with fewer than 20 patients, non-primary outcomes, and non-full-text articles were excluded.

RESULTS

We analyzed 14 studies involving 1,166 patients who underwent CAS via TRA. Procedural success rate was high in 13 studies, with a 95% rate (95% CI; 92%-98%). Crossover to TFA access was observed in 12 studies at 6% (95% CI: 3%-9%). Transradial access failure was reported in four studies, with a rate of 0% (95% CI: 0%-0%). Cannulation failure resulted in a rate of 4% (95% CI: 2%-7%). Asymptomatic radial artery occlusion (ARAO) occurred at a rate of 2% based on eight studies (95% CI: 0%-5%). Forearm hematoma was reported in 10 studies, with an occurrence of 1% (95% CI: 0%-2%). Cerebral vascular attacks (CAV) within 30 days were assessed in 13 studies, indicating a 2% occurrence (95% CI: 1%-2%).

CONCLUSION

The findings suggest that TRA for CAS yields promising outcomes with high success rates and low complication rates. Further research should focus on randomized controlled trials and long-term outcomes to validate and extend findings.

Systematic Review and Meta-Analysis of Transradial Access for Carotid Artery Stenting

There is an increasing number of studies on the transradial approach (TRA) for carotid artery stenting. We aimed to summarize the published data on TRA vs the transfemoral approach (TFA). We searched Science Direct, Embase, PubMed, and Web of Science databases for the relevant literature. Primary outcomes included surgical success and cardiovascular and cerebrovascular complication rates; secondary outcomes included the rates of vascular access-related and other complications. We also compared the crossover rate, success rate, and complications between TRA and TFA carotid stenting. This is the first such meta-analysis regarding TRA and TFA. Twenty studies on TRA carotid stenting were included (n = 1300). Among 19 studies, the success rate of TRA carotid stenting was .951 (95% confidence interval [CI]: .926-.975); death rate was .022 (.011-.032); stroke rate was .005 (.001-.008); radial artery occlusion rate was .008 (.003-.013); and forearm hematoma rate was .003 (-.000 to .006). Among 4 studies comparing TRA and TFA, the success rate was lower (odds ratio: .02; 95% CI: .00-.23) and crossover rate was higher (odds ratio: 40.16; 95% CI: 4.41-365.73) with TRA. Thus, transradial neuro-interventional surgery has a lower success rate than TFA.

Sex differences in outcomes of carotid artery stenting

OBJECTIVE

Existing evidence is inconclusive on whether women after carotid artery stenting (CAS) experience worse outcomes than men.

METHODS

The outcomes of women and men were compared using the data from nationwide retrospective registry between 2015 and 2019. The primary outcome was the incidence of ischemic stroke and all-cause death. Secondary outcomes included the incidence of ischemic stroke, all-cause death, acute occlusion, and acute myocardial infarction. Functional outcomes were the achieving an mRS score of 0-1 and 0-2. Outcomes were assessed at 30 days after CAS.

RESULTS

In total, 9792 patients (1330 women, 8862 men; mean age, 73.8 vs 73.5 years, p = 0.17) were analyzed. Symptomatic stenosis was common in men (52.0% vs. 55.1%; p = 0.03), while ≥50% stenosis after CAS was common in women (3.2% vs. 2.0%; p = 0.005). The primary outcome was no significantly difference in women and men (2.0% vs. 1.9%; adjusted odds ratio [aOR], 1.19; 95% confidence interval [95%CI], 0.75-1.88).The incidence of all-cause death was higher in women (0.9% vs. 0.5%; aOR, 2.45; 95%CI, 1.11-5.39). Functional outcomes were significantly less common in women than in men (mRS0-1, 72.6% vs. 74.8%; aOR, 0.77; 95%CI, 0.63-0.95; mRS0-2, 82.1% vs. 85.6%; aOR, 0.76; 95%CI, 0.60-0.95).

CONCLUSIONS

This study suggests that there was no significant sex differences in the incidence of ischemic stroke and all-cause death at 30 days. However, women have higher rate of all-cause death and poorer functional outcomes at 30 days than men.

Real-World Outcomes of Carotid Artery Stenting in Symptomatic and Asymptomatic Patients With Carotid Artery Stenosis

BACKGROUND

The effectiveness and safety of carotid artery stenting (CAS) are comparable to those of carotid endarterectomy in both symptomatic and asymptomatic patients with carotid artery stenosis, but real-world outcomes are not well-known.

OBJECTIVES

The purpose of this study was to investigate the real-world clinical outcomes of CAS in symptomatic and asymptomatic patients with carotid artery stenosis.

METHODS

We conducted a nationwide retrospective registry study of 156 centers between January 2015 and December 2019. We enrolled consecutive patients with CAS managed by certified specialists from the Japanese Society of Neuroendovascular Therapy. Outcomes between symptomatic and asymptomatic patients were compared. The primary outcome was a composite of ischemic stroke and all-cause death at 30 days after CAS. Secondary outcomes were ischemic stroke, all-cause death, intracranial hemorrhage (ICH), and procedural complications.

RESULTS

We analyzed 9,792 patients (symptomatic, n = 5,351; asymptomatic, n = 4,441). The mean age was 73.5 years, and men were dominant (86.4%). Embolism protection devices were used in 99% of patients. The primary outcome was not significantly different between the symptomatic and asymptomatic groups (120 [2.2%] vs 65 [1.5%]; adjusted OR: 1.30; 95% CI: 0.92-1.83). The incidences of symptomatic ICH, any ICH, acute in-stent occlusion, and hyperperfusion syndrome were significantly more prevalent in the symptomatic group (47 [0.9%] vs 8 [0.2%], aOR: 4.41 [95% CI: 1.68-11.6]; 73 [1.4%] vs 12 [0.3%], aOR: 3.56 [95% CI: 1.71-7.39]; 45 [0.8%] vs 19 [0.4%], aOR: 2.18 [95% CI: 1.08-4.40]; and 102 [1.9%] vs 36 [0.8%], aOR: 1.78 [95% CI: 1.17-2.71], respectively). Other secondary outcomes were not significantly different between the 2 groups.

CONCLUSIONS

The complication rate after specialist-involved CAS at 30 days was low in real-world practice.

Antithrombotic Therapy in Carotid Artery and Intracranial Artery Stent

Optimal platelet inhibition is critical in patients with carotid and intracranial artery stenosis undergoing carotid artery stenting (CAS) and intracranial artery stenting (ICS). Many reports have highlighted the importance of dual antiplatelet therapy (DAPT) in reducing adverse neurological outcomes without a significant increase in bleeding complications during CAS. DAPT has commonly used CAS and ICS, typically with aspirin and clopidogrel, but clopidogrel resistance occurs in approximately 20% of Japanese and other Asian populations. One solution to clopidogrel resistance is using adjunctive cilostazol to suppress the frequency of stroke events and in-stent restenosis after CAS. Other antiplatelet agents such as prasugrel, ticagrelor, cangrelor, and glycoprotein (GP) IIb/IIIa inhibitors are under investigation. The duration of DAPT after CAS remains controversial, as a longer duration of DAPT after CAS is associated with lower rates of readmission for stroke, but increased risk of hemorrhagic complications. Regarding antithrombotic therapy in CAS with concomitant atrial fibrillation, the use of direct oral anticoagulants plus a P2Y12 inhibitor may be suggested for the optimal safety and efficacy of antithrombotic management. For emergent CAS in acute ischemic stroke (AIS), intraprocedural DAPT loading and GP IIb/IIIa inhibitors, as necessary, may improve stent patency without increasing the risk of intracranial hemorrhage. In ICS, aggressive antiplatelet therapy based on an assessment of platelet aggregation is also important to improve clinical outcomes. In addition, rescue stenting for AIS caused by intracranial atherosclerotic stenosis-related large vessel occlusion is gaining attention. GP IIb/IIIa inhibitors have shown promise, but are not approved in Japan. In conclusion, DAPT is essential for the perioperative management of CAS and ICS. Specific perioperative antithrombotic management remains unclear, but the potential benefits of antithrombotic agents must be weighed against the corresponding increased risk of bleeding complications.

Safety and Risk Factors of Carotid Artery Stenting with Simple Distal Filter Protection: A Single-Center Retrospective Study

Objective

Carotid artery stenting embolic protection devices offer various options, among which distal filter protection is the simplest and easiest to handle. However, compared to balloon protection systems, distal filter protection has more embolic complications. Therefore, we explored the risk factors of distal filter protection, intending to achieve a safer carotid artery stenting. This retrospective study was conducted to identify prognostic factors following carotid artery stenting with only distal filter protection from July 2010 to June 2021.

Methods

Information on patient background, procedures and devices, and complications was collected using medical records. The data pertaining to 187 patients were analyzed after excluding the data of patients in whom other protection devices (8 cases) were used. We used FilterWire EZ as the first choice for embolic protection device and SpiderFX when the patients had difficult-to-cross lesions.

Results

The patients' mean age was 71.9 ± 6.9 years, and 72 (38.5%) were symptomatic. Symptomatic (odds ratio: 2.02, p = 0.035) and difficult-to-cross lesions (odds ratio: 3.63, p = 0.0013) were factors independently associated with symptomatic complications.

Conclusion

This retrospective single-center study established independent prognostic factors for carotid artery stenting with distal filter protection. For patients with symptomatic lesions and severe stenosis or bends that are difficult to pass through, it is necessary to be careful when performing carotid artery stenting with distal filter protection.

Short term outcomes of carotid surgery: the real-world experience of a single teaching center

Background

Surgical treatment of symptomatic extracranial carotid stenosis is well established for preventing neurological events and should adhere to optimal quality standards. However, there is growing concern as to whether results of controlled trials are replicable in real-world settings.

Objectives

To assess a symptomatic carotid stenosis population that underwent surgery and its short-term outcomes in a real-world context at a professional training center.

Methods

Observational study using data collected from medical records from January 2012 to January 2023. Patients undergoing operations for other carotid diseases and with concomitant heart surgery were excluded.

Results

A total of 70 patients undergoing angioplasty or carotid endarterectomy were included. Population subsets undergoing angioplasty or endarterectomy were similar. Differences in anesthetic modality and a longer operative time in the carotid endarterectomy subgroup were statistically significant. There were 4 cases of stroke, only 3 of which (2 minor and 1 major) were related to the index lesion. Thus, the rate of major operation-related stroke was 1.43% and the rate of any lesion-related stroke was 4.29%. There was 1 case of AMI in the angioplasty group and there were no deaths in the sample. The overall rate of major adverse cardiovascular events was 5.71%. There were no statistical differences between the endarterectomy and angioplasty groups regarding the main outcomes.

Conclusions

The rates of outcomes of ischemic stroke, acute myocardial infarction, death, and major adverse cardiovascular events at this center are in line with the rates reported by randomized controlled trials, demonstrating the feasibility of carotid surgery in centers with teaching programs.

Complications and outcomes of carotid artery stenting in high-risk cases

OBJECTIVES

Carotid artery stenting is sometimes adapted for some at-risk cases; however, appropriate treatment timing with stroke onset is controversial. This study aims to identify factors that have an impact on complications and outcomes, especially in patients at high risk.

MATERIALS AND METHODS

We examined the characteristics of 152 consecutive patients treated by carotid artery stenting between January 2018 and March 2022 and retrospectively analyzed the risk factors for complications and poor outcomes (modified-Rankin-Scale deterioration), such as patient background, carotid artery stenting risks (access route tortuosity, severe calcification, vulnerable plaque, estimated glomerular filtration rate <30 mL/min/1.73 m2, etc.), characteristics of the stenosis, details of treatment, and treatment timing.

RESULTS

The average North American Symptomatic Carotid Endarterectomy Trial criteria score was 68.3% and the lesion length was 20.5±9.7mm. Among patients, 107 (70.4%) had a carotid artery stenting risk. In high-risk carotid artery stenting cases, symptomatic complications occurred in 32 (30.0%), and the 90-day modified Rankin scale score deteriorated in 15 cases (14.0%). Multivariate analysis showed that cases with triple antithrombotic therapy (p=0.003), stenting within 7 days (p=0.0032), and after 28+ days (p=0.0035) of stroke onset were independently associated factors for complications.

CONCLUSIONS

This study showed that among risk factors, triple antithrombotic therapy in particular was a risk factor for perioperative complications. Carotid artery stenting for patients with stroke after 28 days of onset affects the prognosis. Therefore, although further study is warranted, waiting more than one month for treatment in patients requiring carotid artery stenting is a potential risk.

The Height and Mobility of Protruding Plaque After Carotid Artery Stenting Are Associated with Postoperative Ischemic Lesions

BACKGROUND

Tissue protrusion (TP) is a possible cause of cerebral infarction after carotid artery stenting (CAS). Using optical frequency domain imaging (OFDI) and angioscopy, we investigated the relationship between the morphological features of TP and postoperative new ischemic lesions on magnetic resonance imaging (MRI)-diffusion weighted imaging (DWI) after CAS.

METHODS

Fifty patients who underwent CAS and subsequent poststenting intravascular evaluation using both OFDI and angioscopy were included. CAS was performed for proximal protection via the femoral artery approach, and intravascular evaluation with OFDI and angioscopy were performed after stent placement. We compared the background and poststenting intravascular findings between patients with and without postoperative new ischemic lesions on MRI-DWI.

RESULTS

TP was observed in 42 patients (84%), and postoperative new ischemic lesions on MRI-DWI were observed in 32 patients (64%). The frequency of TP did not differ between the 2 groups, but the height of TP was higher in the DWI-positive group (0.62 mm vs. 0.29 mm, P = 0.0028), and mobile TP was observed only in the DWI-positive group. The height of TP (P = 0.023) was an independent predictor of new periprocedural ischemic brain lesions after CAS, and its cut-off value for mobility was 0.55 mm on the receiver operating characteristic curve (area under the curve, 0.93).

CONCLUSIONS

The height of TP on OFDI and mobile-TP on angioscopy after CAS were associated with postoperative new ischemic lesions on MRI-DWI. The intravascular evaluation using OFDI and angioscopy could be helpful for a detailed evaluation of TP.

Strategy of carotid artery stenting as first-line treatment and carotid endarterectomy for carotid artery stenosis: A single-center experience

Background:

The main surgical options for stenosis of the carotid artery are carotid endarterectomy (CEA) and carotid artery stenting (CAS). The number of CAS procedures performed in Japan greatly exceeds that of CEA procedures. In this study, we used data from a single center to examine CAS and CEA for carotid artery stenosis.

Methods:

The subjects were patients with carotid artery stenosis who underwent CAS or CEA between January 2012 and May 2020. CAS was the first-choice treatment. CEA was used in cases with vulnerable plaques, a relatively low risk of general anesthesia, and no anatomical features disadvantageous for endarterectomy.

Results:

A total of 140 cases (102 CAS and 38 CEA) were examined. There were more elderly patients in the CAS group. The CEA group had a higher rate of vulnerable plaques and only one case with an unfavorable anatomy for CEA. Major adverse events (stroke) occurred in two CAS cases. In multivariate logistic analysis, postoperative ischemic lesions were independently associated with age (odds ratio [OR] = 1.13, 95% confidence interval [CI]: 1.01–1.26, P = 0.026) and vulnerable plaque (OR = 5.54, 95% CI: 1.48–20.70, P = 0.011) in the CAS group, but not in the CEA group.

Conclusion:

The results reflect the treatment algorithm at our hospital, indicating that triage is accurate. Thus, it is beneficial to assign cases based primarily on plaque vulnerability and anatomical risk for CEA, and to not hesitate to perform CEA simply because of old age. CAS as first-line treatment and CEA are effective and safe, which reflect the treatment situation in Japan.

Trans-cell Approach through Closed-cell Stent for Middle Meningeal Artery Embolization in Recurrent Chronic Subdural Hematoma

We report a case of recurrent chronic subdural hematoma (CSDH) treated using the trans-cell approach through a closed-cell stent for middle meningeal artery embolization (MMAE). A 77-year-old man with acute ischemic stroke due to anterior circulation tandem occlusion was treated with intracranial thrombectomy and carotid artery stenting using a closed-cell stent 5 years ago. He experienced head trauma after a fall, which then developed into a CSDH. Burr hole surgery was performed twice, followed by MMAE considering the high possibility of recurrence due to antiplatelet therapy and brain atrophy after ischemic stroke. A distal access catheter was inserted into the external carotid artery through the closed-cell stent, and a microcatheter was navigated in the middle meningeal artery. The anterior and posterior convexity branches were embolized with 16.7% N-butyl cyanoacrylate. The postoperative course was favorable, and CT at 3-month follow-up showed a decrease in the hematoma. Even after the placement of the closed-cell stent, endovascular treatment of the external carotid artery is possible and can be a therapeutic option using the trans-cell approach.

Renal Dysfunction is the Strongest Prognostic Factor After Carotid Artery Stenting According to Real-World Data

PURPOSE

Through the progression of devices, the adaptation of carotid artery stenting (CAS) has been expanded according to the non-inferiority of CAS for carotid endarterectomy reported by several randomized control trials. To maintain favorable outcomes, identifying prognostic factors is essential for optimizing treatment indications and periprocedural management. This study focused on the prognostic factors of CAS using real-world data.

METHODS

This retrospective multicenter cohort study aimed to identify the prognostic factors after CAS using real-world data from the stroke registry of Yokohama (STrOke Registry of Yokohama; STORY) from January 1, 2018 to May 31, 2021. Patient characteristics, procedural factors, complications, and prognoses were collected using medical records.

RESULTS

Data from 107 patients were enrolled in this study after excluding those with insufficient data (2 cases). The mean participant age was 74.9±8.2 years, and 66 patients (61.7%) were symptomatic. Symptomatic lesions were a significant prognostic factor in the overall analysis (p=0.003). A multivariate analysis showed that the estimated glomerular filtration rate (eGFR) (odds ratio: 1.11, p=0.003) and staged CAS (odds ratio: 38.9, p=0.04) were independent prognostic factors. The odds ratio and relative risk of mRS deterioration when eGFR was under 49 mL/min/1.73 m² compared with when eGFR was above 49 mL/min/1.73 m² were 5.2 and 3.74, respectively.

CONCLUSIONS

In this real-world multicenter study, we established independent prognostic factors for CAS using high totality data. For patients with symptomatic lesions and low eGFR (≤49 mL/min/1.73 m²), indication for treatment should be considered strictly.

Antiplatelet Loading Effects Prior to Endovascular Treatment: Carotid Artery Stenosis versus Unruptured Cerebral Aneurysms

Objective

Carotid artery stenosis and cerebral aneurism may have different platelet functions and antiplatelet responses because these diseases have different etiologies. In this study, we compared the antiplatelet loading effects prior to endovascular treatment between carotid artery stenosis and unruptured cerebral aneurysm (UCA) patients.

Methods

Nine patients with asymptomatic carotid artery stenosis (ACS), 14 with symptomatic carotid artery stenosis (SCS), and 20 with unruptured cerebral aneurysms were enrolled in this study. Antiplatelet (aspirin + clopidogrel) loading effects prior to endovascular treatment were evaluated using light transmission aggregometry and platelet aggregate detection methods.

Results

Although there are differences in the prevalence of atherosclerosis risk factors, maximum aggregation rates in light transmission aggregometry and platelet aggregation-prone properties were not different in the three disease groups.

Conclusion

Preoperative dual antiplatelet therapy with aspirin and clopidogrel may be appropriate for both carotid artery stenosis and cerebral aneurism patients even though their conditions and background factors differ.

Periprocedural Variability of Platelet Functions in Carotid Artery Stenting: An Analysis Using VerifyNow

Objective

The assessment of platelet functions is necessary to prevent both thromboembolic and hemorrhagic complications under dual antiplatelet therapy (DAPT). Using the VerifyNow (Accumetrics, Inc., San Diego, CA, USA) assay, this study aimed to reveal time-dependent changes in platelet functions after carotid artery stenting (CAS).

Methods

We enrolled retrospectively 43 patients who underwent CAS under DAPT. Aspirin reaction unit (ARU) and P2Y12 reaction unit (PRU) values were determined on the day before and on days 1, 3, and 7 after the procedure. Multiple comparison tests (MCTs) were performed among ARU and PRU measurement points, and the proportions of hypo- and hyper-responses were compared.

Results

The median ARU values were 408 (interquartile range: 392-497) before CAS and 418 (405-470) on day 1, 405 (393.0-460.5) on day 3, and 402 (388.5-477.5) on day 7 (not significant in MCTs). The percentages of hypo-responses were 16.3%, 7.0%, 2.3%, and 7.0%, respectively (p = 0.11). The significantly different median PRU values were 173 (116.5-209.5), 233 (166.5-273.5), 139 (70.5-205.5), and 51 (9.0-79.5), respectively. The median PRU was before the procedure within the therapeutic range but exceeded the upper cutoff on day 1 and was below the lower cutoff on day 7. The percentages of hypo-responses were 14.0%, 51.2%, 18.6%, and 11.6%, respectively (p <0.001) and the percentages of hyper-responses were 9.3%, 2.3%, 23.3%, and 62.8%, respectively (p <0.001).

Conclusion

In the periprocedural CAS period, ARU values were stable, but PRU values showed time-dependent changes. PRU values were above the therapeutic range the day after CAS but decreased below this range on day 7.

Transradial approach for neurointerventions: a systematic review of the literature

Background

Despite the recent increase in the number of publications on diagnostic cerebral angiograms using transradial access (TRA), there have been relatively few regarding TRA for neurointerventional cases. Questions of feasibility and safety may still exist among physicians considering TRA for neurointerventional procedures.

Methods

A systematic literature review was performed following PRISMA guidelines. Three online databases (MedLine via PubMed, Scopus and Embase) were searched for articles published between January 2000 and December 2019. Search terms included “Transradial access”, “Radial Access”, “Radial artery” AND “Neurointerventions". The reference lists of selected articles and pertinent available non-systematic analysis were reviewed for other potential citations. Primary outcomes measured were access site complications and crossover rates.

Results

Twenty-one studies (n=1342 patients) were included in this review. Two of the studies were prospective while the remaining 19 were retrospective. Six studies (n=616 patients) included TRA carotid stenting only. The rest of the studies included treatment for cerebral aneurysms (n=423), mechanical thrombectomy (n=127), tumor embolization (n=22), and other indications (n=154) such as angioplasty and stenting for vertebrobasilar stenosis, balloon test occlusion, embolization of dural arteriovenous fistula and arteriovenous malformation, chemotherapeutic drug delivery, intra-arterial thrombolysis, and arterial access during a venous stenting procedure. Two (0.15%) major complications and 37 (2.75%) minor complications were reported. Sixty-four (4.77%) patients crossed over to transfemoral access for completion of the procedure. Seven (0.52%) patients crossed over due to access failure and 57 (4.24%) patients crossed over to TFA due to inability to cannulate the target vessel.

Conclusion

This systematic review demonstrates that TRA has a relatively low rate of access site complications and crossovers. With increasing familiarity, development of TRA-specific neuroendovascular devices, and the continued reports of its success in the literature, TRA is expected to become more widely used by neurointerventionalists.

Thirty-Day Outcome of Carotid Artery Stenting in Elderly Patients: A Single-Center Experience

BACKGROUND

The safety of carotid artery stenting (CAS) in elderly patients is controversial. The aims of this study were to evaluate 30-day outcomes after CAS in elderly patients (≥70 years old) and to investigate risk factors for postoperative incidence of major adverse clinical events (MACE) to improve CAS safety based on clinical evidence in this specific subgroup of patients.

METHODS

The data set included patients who underwent CAS between 2001 and 2017 at Xuanwu Hospital, Capital Medical University. The primary outcome variable was 30-day postoperative incidence of the following MACE: death, myocardial infarction, and ipsilateral stroke. Univariate and multivariate analyses were performed to identify high-risk patients and procedural characteristics associated with MACE.

RESULTS

A total of 1029 elderly patients who underwent CAS for carotid artery stenosis were identified and analyzed. The incidence of postoperative MACE was 3.01% (n = 31 cases [5 deaths, 24 strokes, and 2 myocardial infarctions]). After multivariate analysis, independent predictors of MACE included a family history of stroke (odds ratio [OR] = 3.817; 95% confidence interval [CI], 1.227-11.876; P = 0.021), symptomatic status (OR = 2.650; 95% CI, 1.210-5.806; P = 0.015), and modified Rankin Scale score ≥3 (OR = 4.594; 95% CI, 1.708-12.352; P = 0.003). Hyperlipidemia was not an independent risk factor (OR = 1.597; 95% CI, 0.745-3.425; P = 0.229).

CONCLUSIONS

At our center, CAS was safely performed in elderly patients. A family history of stroke, symptomatic status, and modified Rankin Scale score ≥3 indicating a neurologic deficit increased the risk of 30-day postoperative MACE.

Procedural success with radial access for carotid artery stenting: systematic review and meta-analysis

BACKGROUND

Femoral access is the traditional approach for endovascular carotid artery stenting. Radial access is increasingly used as an alternative approach due to its known anatomical advantages in patients with unfavorable aortic arch morphology via the femoral approach and its excellent access site safety profile. Our objective was to analyze procedural success using radial access for carotid artery stenting as reported in the literature.

METHODS

Three online databases were systematically searched following PRISMA guidelines for studies (n ≥20) using radial artery access for carotid artery stenting (1999-2018). Random-effects meta-analysis was used to pool the procedural success (successful stent placement with no requirement for crossover to femoral access), mortality, and complication rates associated with radial access.

RESULTS

Seven eligible studies reported procedural success outcomes with a pooled meta-analysis rate of 90.8% (657/723; 95% CI 86.7% to 94.2%; I²=53.1%). Asymptomatic radial artery occlusion occurred in 5.9% (95% CI 4.1% to 8.0%; I²=0%) and forearm hematoma in 1.4% (95% CI 0.4% to 2.9%; I²=0%). Risk of minor stroke/transient ischemic attack was 1.9% (95% CI 0.6% to 3.8%; I²=42.3%) and major stroke was 1.0% (95% CI 0.4% to 1.8%; I²=0%). There were three deaths across the seven studies (0.6%; 95% CI 0.2% to 1.3%; I²=0%). The meta-analysis was limited by statistically significant heterogeneity for the primary outcome of procedural success.

CONCLUSION

Radial access for carotid artery stenting has a high procedural success rate with low rates of mortality, access site complications, and cerebrovascular complications. The potential benefits of this approach in patients with unfavorable aortic arch access should be explored in a prospective randomized trial.