Carotid Artery Stenting Cases Research Articles

Abstract TMP68: Proximal Balloon Occlusion With Forced Aspiration (POWER) Technique Should Be Effective in Preventing Distal Microembolization During Carotid Artery Stenting With the Filter Protection Device

Purpose: Since the balloon protection device became unavailable in Japan three years ago, the DWI-positive rate after carotid artery stenting (CAS) has increased. We have developed a Proximal balloon Occlusion With forcEd aspiRation (POWER) technique to prevent distal embolization in CAS with the filter protection device. The concept of this technique was to standardize the three points: (1) aspiration force, (2) timing of aspiration and (3) use of balloon guiding. To standardize (1), a VACLOK (vacuum pressure) syringe-like system was used instead of manual aspiration, so that the same aspiration force was applied. To standardize (2), aspiration was to be initiated just before PTA balloon deflation during pre- and post-dilatation. Methods: From June 2020 to the present, CAS cases using the Filter protection device were enrolled and divided into two groups before and after the introduction of the POWER technique. Patient backgrounds, carotid artery characteristics (symptomatic, stenosis rate and length, MRI and echographic findings), PTA balloon size, stent type, the postoperative DWI positive rate and the number of DWI spots, and the symptomatic stroke rate were compared between the two groups, respectively. Results: Of the 55 CAS cases, 36 were enrolled in the without-POWER group and 19 in the with-POWER group. Between the two groups, postoperative DWI positivity was 32 (88.9%) vs. 9 (47.4%) (p<0.001), DWI spot lesions (n, median (quartiles)) was 9 (3-20) vs. 0 (0-2) (p<0.001), and symptomatic stroke was 6 (16.7%) vs. 0 (0%) (p=0.06), all with-POWER group were less common. Symptomatic stenosis (63.9% vs. 94.7%, p<0.05) was more common in the with-POWER group. There were no differences in age, gender, stenosis rate and length, open cell stent, PTA balloon size, MRA TOF high, MRI T1BB high, hypoechoic plaque, HT, DL, DM, CKD, smoking or DAPT use. Conclusion: POWER technique was associated with lower postoperative DWI positivity and lesion counts in CAS with filter protection device.

Abstract 133: Safe Guiding Catheter Navigation in Carotid Artery Stenting for Low‐positioned Common Carotid Lesions: “No‐touching” Technique

Introduction In carotid artery stenting (CAS), a guiding catheter (GC) placement to the appropriate position is the first step of the successful procedure. In normal settings, GC is navigated along with stable support of guidewire and inner‐catheter which are sent distally to external carotid artery. In cases of low‐positioned common carotid artery (CCA) lesions, however, safe GC placement without touching lesions is often difficult. Herein, we report the technique of safe GC navigation of “no‐touching” to the low‐position CCA plaque using Newton‐shaped stiff inner‐catheter. Methods We reviewed CAS procedures with low‐positioned CCA lesions using “no‐touching” technique: a balloon guiding catheter (BGC) was coaxially advanced in combination with 4‐French Newton‐shaped stiff inner‐catheter (Newton‐T®, Medikit, Tokyo, Japan). With its advantage of shape and stiffness buffering the kickback force with support of lesser curvature of aortic arch, BGCs were navigated to the appropriate position without touching to the plaques. Results The technique were applied in 5 cases (age: 73‐85 years old, 4 males, 4 left‐sided lesions) among the 37 consequent CAS cases. GC fixation by GooseNeck snare was used concurrently in 2 cases. BGCs were successfully navigated without touching plaques in all cases. CAS procedures were subsequently undergone and no complication was observed. Conclusion GC navigation using “no‐touching” technique with Newton‐T catheter was safe and useful in CAS procedures for low‐positioned CCA lesions.

Importance of preoperative coronary artery examination before performing procedures for carotid artery stenosis.

Carotid artery stenosis and coronary artery disease (CAD) often occur simultaneously, with one being an important risk factor in the treatment of the other. This study aimed to perform coronary computed tomography angiography (CTA) as a preoperative evaluation for carotid artery stenosis treatment. We retrospectively reviewed cases of carotid endarterectomy (CEA) and carotid artery stenting (CAS) performed at our hospital as well as CAD complications. Among the 54 and 166 CEA and CAS cases from May 2014 to February 2022, 53 and 148 cases were analyzed for atherosclerotic stenosis, respectively. Among those who underwent CEA and CAS, 7 (13.2%) and 17 (11.5%) received percutaneous coronary intervention (PCI), 44 (83%) and 97 (65.5%) received symptomatic carotid stenosis treatment and 43 (81.1%) and 110 (74.3%) received preoperative coronary CTA, respectively. Coronary artery stenosis was noted in 14 (32.6%) and 46 (41.8%) patients who had undergone CTA in the CEA and CAS groups, respectively. PCI before carotid treatment was performed in two cases in the CEA group (3.8% of all patients who had undergone CEA) and eight cases in the CAS group (5.4% of all patients who had undergone CAS). Screening may detect asymptomatic coronary artery lesions in carotid artery stenosis even in patients without chest symptoms and suspicion of ischemic heart disease. Preoperative coronary artery screening is important considering that pre and postoperative coronary artery treatment may improve long-term prognosis.

Abstract Number ‐ 148: Emergent Carotid Artery Stenting On Acute Stroke Patients With Carotid Occlusion: Benefit Or Harm?

Introduction Almost one out of four patients with acute middle cerebral artery occlusion also have ipsilateral internal carotid artery occlusion (ICAO). The interventions for acute stroke due to extracranial ICAO with or without intracranial occlusions are still a challenge. Case series reported early revascularization reduced stroke recurrence and improved outcomes. The benefits of this intervention on hyperacute ischemic strokes (within 6 hours) were much less known. We reported here two hyperacute stroke patients who emergent CAS on ICAO. Methods Electronic medical charts were reviewed, assessing intracranial hemorrhage (ICH) in two hyperacute stroke patients resulting from emergent carotid artery stenting (CAS) on the occluded internal carotid artery (ICA). Results Case description:The first patient was a 60‐year‐old male who had acute right hemiparesis, aphasia, and left gaze deviation with NIHSS12. The last known normal was five hours ago. Head and neck CT angiography (CTA) showed left anterior M2 branch artery occlusion and left ICAO. Head CT perfusion (CTP) showed a small core infarct with a large perfusion mismatch. Emergent CAS was performed without distal embolic protection (DEP) and followed by distal mechanical thrombectomy (MT). TICI 2B recanalization was achieved. After CAS, aspirin and clopidogrel were administrated. He had a large left MCA and PCA stroke from fetal PCA. A few days later, the patient developed large intraparenchymal hemorrhage (IPH) and intraventricular hemorrhage (IVH). He expired shortly. The second was a 52‐year‐old male had acute right facial droop, aphasia, dysarthria, and decreased consciousness (NIHSS 8). CTA showed left ICAO but patent intracranial arteries. CT perfusion showed a large mismatch without core infarction. He received intravenous tPA and had emergent CAS with a DEP. Aspirin 600 mg was administrated afterward. A few hours later, he had worsened weakness. Head CT showed left IPH, IVH, and subarachnoid hemorrhages with cerebral edema, and midline shift. He was medically managed for a prolonged stay and was discharged to a rehabilitation facility. Conclusions We presented two consecutive cases of emergent revascularization of ICAO in hyperacute stroke carried a high risk of ICH with poor outcome. Our online database search found that only a few case series of emergent CAS on ICAO were reported. Overall, emergent CAS carried about 20% risk of ICH and high mortality. Other series reported angioplasty on stenotic or occluded cervical ICA lesions with MT on distal occlusions had less hemorrhagic risk because there was no need fordual antiplatelet treatment. Most emergent CAS cases were performed on tandem occlusions for faster direct access and better efficacy of distal recanalization. A futurestudy comparing hemorrhagic risk betweenemergent CAS versus angioplasty of ICAO in patients with tandem occlusions can help to establish a standard MT protocol. For isolated ICAO with patent intracranial arteries from good collaterals, CTP may not be a good guidance tool for decision‐making of emergent CAS as it can falsely show mismatch from existing collaterals due to occlusion. A randomized clinical trial of comparison of medical management versus emergent CAS on those patients is warranted.

Long-term outcomes of carotid artery stenting in patients with carotid artery stenosis: A single-center 14-year retrospective analysis.

Carotid artery stenting (CAS) is currently widely used for the treatment of carotid artery stenosis. The objective of this study was to analyze the outcomes of CAS performed in a single institution. We retrospectively analyzed 313 CAS cases from January 2007 to December 2020, including 206 (66%) symptomatic and 107 (34%) asymptomatic cases. Procedure-related morbidity and mortality were assessed. Rates of periprocedural (≤30 days after CAS) and postprocedural ipsilateral strokes (>30 days after CAS) were also assessed. Logistic regression analysis was used to identify risk factors for the periprocedural complication, in-stent restenosis (ISR), and ipsilateral stroke. The success rate of CAS was 98%. Among 313 cases, 1 patient died due to hyperperfusion-related intracerebral hemorrhage (ICH). The CAS-related mortality rate was 0.31%. The overall incidence of periprocedural complications is 5.1%. A risk factor for periprocedural complication was a symptomatic carotid artery stenosis (7.3% vs. 0.9%, p=0.016). Twenty cases of ISR occurred during 63.7±42.1 months of follow-up. The overall incidence of ISR was 10.2% (20/196). A risk factors for ISR were diabetes mellitus (17.6% vs. 5.7%, p=0.008) and patients who used Open-cell stents (19.6% vs. 6.9%, p=0.010). The overall incidence of ipsilateral stroke is 5.6%. A risk factors for ipsilateral stroke was ISR (95% CI, p=0.002). CAS is a safe and effective procedure for carotid artery stenosis. Although the incidence of complications is low, fatal complication such as hyperperfusion- related ICH can occur. To prevent hyperperfusion-related ICH, several methods such as strict blood pressure (BP) control, intentional less widening of stenotic segment should be used. To prevent ISR or stroke occurrence, special attention should be paid to patients who have ISR or ipsilateral stroke risk factors.

Usefulness of cone-beam computed tomography to predict residual stenosis after carotid artery stenting.

The long-term durability of carotid artery stenting (CAS) may be determined by various factors; however, residual stenosis is a known risk factor for in-stent restenosis. The authors of this article utilized cone-beam computed tomography (CBCT) in angiosuite to investigate plaque features affecting the character and quality of stent expansion after CAS. Forty-two CAS cases with both pre- and post-CAS CBCT evaluations were included in this retrospective analysis. Five features derived from pre-CAS images were tested: (1) eccentricity, (2) overballoon, (3) maximum plaque thickness, (4) calcification barrier, and (5) stenotic degree. For post-CAS CBCT, stent configuration was assessed if the stent was expanded and oval or round in shape as well as outward or inward in orientation. Variables were tested if they were associated with oval expansion, outward expansion, and 20% residual stenosis after CAS. Oval or outward expansion is directly related to residual stenosis. The oval expansion was associated with maximum plaque thickness, and outward expansion was associated with the presence of a calcification barrier. Variables related to > 20% residual stenosis were the maximum plaque thickness, calcification barrier, and pre-CAS stenotic degree. CBCT for carotid stenosis may provide valuable information about plaque features, especially calcification features that may interfere with the angioplasty effect, as well as the characteristics and quality of stent expansion. Residual stenosis > 20% was associated with calcification barrier, maximum plaque thickness, and pre-CAS stenotic degree.

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

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. 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. 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. 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.

Evaluation of Robotic-Assisted Carotid Artery Stenting in a Virtual Model Using Motion-Based Performance Metrics

Purpose: Robotic-assisted carotid artery stenting (CAS) cases have been demonstrated with promising results. However, no quantitative measurements have been made to compare manual with robotic-assisted CAS. This study aims to quantify surgical performance using tool tip kinematic data and metrics of precision during CAS with manual and robotic control in an ex vivo model. Materials and Methods: Transfemoral CAS cases were performed in a high-fidelity endovascular simulator. Participants completed cases with manual and robotic techniques in 2 different carotid anatomies in random order. C-arm angulations, table position, and endovascular devices were standardized. Endovascular tool tip kinematic data were extracted. We calculated the spectral arc length (SPARC), average velocity, and idle time during navigation in the common carotid artery and lesion crossing. Procedural time, fluoroscopy time, movements of the deployed filter wire, precision of stent, and balloon positioning were recorded. Data were analyzed and compared between the 2 modalities. Results: Ten participants performed 40 CAS cases with a procedural success of 100% and 0% residual stenosis. The median procedural time was significantly higher during the robotic-assisted cases (seconds, median [interquartile range, IQR]: 128 [49.5] and 161.5 [62.5], p=0.02). Fluoroscopy time differed significantly between manual and robotic-assisted procedures (seconds, median [IQR]: 81.5 [32] and 98.5 [39.5], p=0.1). Movement of the deployed filter wire did not show significant difference between manual and robotic interventions (mm, median [IQR]: 13 [10.5] and 12.5 [11], p=0.5). The postdilation balloon exceeded the margin of the stent with a median of 2 [1] mm in both groups. Navigation with robotic assistance showed significantly lower SPARC values (–5.78±3.14 and –8.63±3.98, p=0.04) and higher idle time values (8.92±8.71 and 3.47±3.9, p=0.02) than those performed manually. Conclusions: Robotic-assisted and manual CAS cases are comparable in the precision of stent and balloon positioning. Navigation in the carotid artery is associated with smoother motion and higher idle time values. These findings highlight the accuracy and the motion stabilizing capability of the endovascular robotic system. Clinical Impact Robotic assistance in the treatment of peripheral vascular disease is an emerging field and may be a tool for radiation protection and the geographic distribution of endovascular interventions in the future. This preclinical study compares the characteristics of manual and robotic-assisted carotid stenting (CAS). Our results highlight, that robotic-assisted CAS is associated with precise navigation and device positioning, and smoother navigation compared to manual CAS.

Carotid Endarterectomy and Carotid Artery Stenting for Symptomatic Carotid Stenosis: An Experience of a Hybrid Neurosurgeon in a Developing Nation.

Stenosis of the ICA is an important cause of ischemic stroke and associated morbidity and mortality. Carotid artery stenting (CAS) and carotid endarterectomy (CEA) help to prevent impending or subsequent ischemic stroke in such patients. To study the outcome and adverse events associated with CEA and CAS. To determine the generalization of results obtained with multicentric trials such as CREST, etc., by comparing the results obtained by a single neurosurgeon in a community setting. From Jan 2014-Dec 2017, 80 patients presented with symptomatic carotid stenosis. Out of these 80 patients, 65 underwent intervention; 34 patients underwent CEA and 31 patients underwent CAS. Pre-defined variables like age, sex, and degree of stenosis were assessed as potential risk factors, and the patients' clinical features, radiological imaging, and procedural complications were documented. The primary outcome of procedure-related stroke, major adverse events (MAEs), and death at 30 days follow-up and long-term outcomes of restenosis at 1 year were analyzed. Peri-procedural stroke occurred in 2 cases (6.4%) of CAS; one suffered an ischemic stroke and other suffered a hemorrhagic stroke. Three cases of CEA suffered procedure-related events; one (2.9%) suffered TIA while the other two developed postoperative local hematoma without neurological deficit; one was treated conservatively while the other required re-exploration due to pressure symptoms. Restenosis occurred in one case that underwent CAS. CAS and CEA are complementary approaches in treating symptomatic carotid stenosis even when performed by a single hybrid neurosurgeon as results obtained are commensurable to major studies like CREST.

Abstract 1122‐000174: Stroke Risk of Carotid Artery Stenting Using Balloon‐Guide Catheter Versus Distal Embolic Protection Devices

Introduction : Prevention of distal embolization during carotid artery stenting (CAS) is a key element of procedural technique and is standardly performed using distal protection devices (DPDs). Data in support of DPDs, however, are limited. Here, we present our experience of proximal occlusion using a balloon guide catheter (BGC) during CAS as the primary method of distal embolic protection. Methods : We conducted a retrospective review of patients undergoing CAS at our healthcare system between January of 2018 to March of 2021. Procedures were categorized by embolic protection strategy: DPD or BGC (with or without DPD). Emergent cases were defined as patients receiving CAS within <24 hours of presenting with an ischemic stroke or TIA ipsilateral to the carotid disease side. Severe stenosis was defined as 70–99% per NASCET criteria. The primary outcome was rate of procedural ischemic stroke between the DPD and BGC groups, and was defined as acute focal neurological deficit lasting for ≥ 24 hours following CAS related to an embolic event during the procedure. Results : A total of 126 CAS procedures were performed during the study period. 91 cases were performed under proximal BGC protection (of which 24 also included DPD usage) and 35 CAS cases via DPD as a primary mean for embolic protection. The median age for the cohort was 68 [IQR 62‐76], 37% females, 31% (n = 39) cases were treated emergently, and elective cases were 69% (n = 87). Baseline characteristics were similar in both groups except for hyperlipidemia (BGC vs DPD, 71.4% vs 42.9%; p = 0.003) and history of smoking (BGC vs DPD, 56% vs 34.4%; p = 0.029). Severe carotid stenosis was present in 80.2% BGC group and 77.1% in DPD (p = 0.573). Post‐stenting balloon angioplasty was more frequent in the BGC group as compared with DPD (54% vs. 26%, BGC vs. DPD, p = 0.005). Procedural embolic stroke rates were low in both groups, and not significantly different (1.1% vs. 2.9%, BGC vs. DPD, p = 0.48). Conclusions : CAS with BGC as the primary means of distal embolic protection showed comparable, low rates of procedural embolic ischemic events compared to those with DPD. These findings suggest BGC embolic strategies may be a viable alternative to DPD usage.

Abstract P540: Safety of Carotid Artery Stenting Without Embolic Protection: A Single Centre Experience

Introduction: One of the most feared complications of carotid revascularization, including carotid artery stenting (CAS), is peri-procedural ischemic stroke. Several studies suggest that the use of a distal embolic protection device (EPD), as well as over-sized pre- and post-stenting balloon angioplasty, may increase the risk of dislodgement of atheromatous plaque in patients undergoing CAS. The CREST trial, that mandated the use of an EPD, had a peri-procedural ischemic stroke rate of 4.1%. We hypothesize that our technique of stenting without the use of an EPD and sub-maximal angioplasty will have a low risk of peri-procedural complications. Methods: A retrospective review was conducted of consecutive cases of ICA stenting without use of an embolic protection device between January 2012 and June 2020 at a Canadian stroke centre. Data was extracted from the patient electronic medical record and Picture Archives and Communications Systems (PACS). Both symptomatic and asymptomatic CAS cases were included. Results: A total of 220 patients were included in the study, with a median age of 70 years (range 39-93 years), and 83 patients (38%) were female. The vast majority of patients were symptomatic (216 patients [98%]). A large portion of patients had a contralateral ICA occlusion or near occlusion (56 patients [25%]). In the majority of cases, a Precise Cordis RX carotid stent (Cordis) was placed. There were four patients with peri-procedural ischemic strokes (1.8%), with two occurring 8-30 days after stenting. There was one case of acute stent occlusion associated with an ischemic stroke. Two patients (less than 1%) had hyperperfusion syndrome after CAS. Median length of stay following the procedure was one day. Conclusions: In this single centre series, the peri-procedural risks of CAS without using an EPD are low. The ischemic stroke rate is less than 2%, lower than what has been reported in large randomized controlled trials using embolic protection.

Distal radial artery (snuffbox) access for carotid artery stenting - Technical pearls and procedural set-up.

To report use of distal radial artery (dRA) access for carotid artery stenting (CAS) and to discuss procedural setup and technical considerations for a successful intervention. A retrospective review of our prospective neurointerventional database of CAS was conducted between May 2019 and March 2020. All CAS cases via dRA in the anatomical snuffbox were identified. Patient demographics, clinical information, procedural and radiographic data was collected. 22 CAS procedures in 20 patients via dRA were identified. Patients' mean age was 69.4 years (range 53-87 years). 3 patients were female. Mean radial artery diameter was 2.1 mm (range 1.6-2.8 mm). dRA access was achieved in all cases. Conversion to femoral access was required in 2 cases (9.1%) due to persistent radial artery vasospasm resulting in patient discomfort despite multiple additional doses of intraarterial vasodilators and added intravenous sedation as well as tortuous vessel anatomy and limited support of the catheters in a type 3 aortic arch for left CAS. Our preliminary experience with dRA access for CAS suggests this approach to be feasible and safe for patients. Technical considerations are important and preprocedural planning is necessary for a successful intervention. Catheter systems and devices specifically designed for radial access are needed to enable more interventionalists to safely perform neurointerventional procedures via wrist access.

The Usefulness of Prasugrel as Rescue Medication in Neuroendovascular Therapy.

In neuroendovascular therapy, clopidogrel resistance and thrombosis are common problems. In such cases, we use prasugrel as rescue medication, and we clarified its usefulness. We retrospectively investigated 199 consecutive cases of neuroendovascular therapy performed at our hospital from April 2016 to March 2018, and examined the safety and effectiveness of prasugrel. There were 14 cases of prasugrel administration: six cases of coil embolization for cerebral aneurysm, five cases of carotid artery stenting (CAS), and three other cases.The reasons for prasugrel administration were as follows: emergency stent use in four cases, intraoperative thrombosis in three cases, intra-stent thrombosis after CAS in three cases, and others in four cases. In all cases, it was used in combination with aspirin and the median duration of administration was 212 days. Regarding its safety, there was one hemorrhagic complication at the puncture site for which the involvement of prasugrel was unable to be excluded, but it was improved by conservative treatment and there was no major hemorrhage such as intracranial hemorrhage. Regarding its efficacy, in one case, the thrombus during coil embolization did not completely disappear after prasugrel administration and additional mechanical thrombolysis was required. However, no new thrombosis was observed during prasugrel administration in all 14 cases. Prasugrel may be useful as a rescue medication in neuroendovascular therapy.

Carotid Artery Endarterectomy vs. Stenting: Are There Any Relevant Morphological and Hemodynamic Implications?

Introduction: Carotid endarterectomy (CEA) and carotid artery stenting (CAS) are interventional therapeutic alternatives for the treatment of carotid stenosis (CS), which is partially triggered by atherogenic hemodynamic conditions regulated from the bifurcation morphology. The predictive potential of morphological and hemodynamic features was recently examined in the post-CEA setting, suggesting that arteriotomy repair should avoid a large widening of the carotid bulb, which is linked to restenosis via the generation of flow disturbances [1,2]. Here, we study the impact of CAS vs. CEA with patch-plasty on carotid bifurcation geometry and hemodynamics, supported by patient-based computational simulations. Methods: After digitally recording CT data of patients treated with CAS (n=2) or CEA (n=2), the 3D carotid bifurcation geometries were reconstructed. As geometry shapes the flow, which is in turn implied in the restenosis process, a centerline-based geometric analysis was carried out on the reconstructed geometries (Figure 1). Hemodynamics-informed geometric descriptors were calculated, i.e., carotid flare (a measure of the carotid bulb expansion) and tortuosity, as suggested elsewhere [2-3]. Complementary, computational fluid dynamics simulations were performed to determine the extent of luminal surface area exposed to low and oscillatory wall shear stress, a hemodynamic condition widely recognized as “disturbed shear”, with acknowledged atherogenic [4] and restenosis risk potential [2]. Results: A different reshaping of the carotid bifurcation was observed as a consequence of CAS vs. CEA. In general, stent implantation led to reduced tortuosity, while no significant variation was observed for flare with respect to the pre-operative geometry. Conversely, CEA led to a significant increase of flare and to minor variations of tortuosity. As for hemodynamics, larger areas at the luminal surface exposed to disturbed shear were observed in stented cases (Figure 2). Conclusion: CAS and CEA reshape the carotid bifurcation in a different way, suggesting that different restenosis trajectories are possible in the long term. The larger disturbed shear area in CAS cases might be ascribed to the decrease in tortuosity [2-3], although the complex interaction between geometry and the underlying disturbed shear will be subject of future investigations. The present results confirm very recent findings [2] suggesting that geometric and hemodynamic analyses hold potential for the virtual exploration of personalized post-operative scenarios, providing useful indications on (1) the best treatment strategy (e.g., CEA vs. CAS), and (2) the stratification of post-intervention restenosis risk. Disclosure: Nothing to disclose

Association between the choice of anesthesia and in-hospital outcomes after carotid artery stenting

ObjectiveSeveral prior studies have shown lower risk of myocardial infarction (MI) in carotid artery stenting (CAS) compared with carotid endarterectomy. This is likely because the majority of endarterectomies are performed under general anesthesia (GA), whereas CAS is mainly performed under local anesthesia (LA). Performing CAS under GA may reverse its minimally invasive benefits. The aim of this study was to compare the safety profile of CAS-GA with that of CAS-LA. MethodsA retrospective analysis of the Vascular Quality Initiative database from 2005 to 2017 was performed. Primary outcomes included major adverse cardiac events (MACE), a composite of in-hospital death and MI, and postoperative neurologic events. Multivariable logistic models, and coarsened exact matching were used to evaluate the association between the primary outcomes and anesthesia technique. ResultsOf 12,919 CAS cases performed, 2024 (15.7%) were under GA. Comparing CAS-GA with CAS-LA in the overall cohort, CAS-GA had significantly higher crude rates of in-hospital mortality (2.1% vs 0.5%), MI (1.3% vs 0.7%), composite MACE (3.1% vs 1.2%), and ipsilateral stroke (2.3% vs 1.6%). Patients undergoing CAS-GA also had higher rates of dysrhythmia (3.0% vs 2.2%), acute congestive heart failure (1.6% vs 0.7%) and perioperative hypertension (13.2% vs 9.4%), and were more likely to have a length of hospital stay of more than 4 days (prolonged length of stay) (17.6% vs 8.5%) compared with those undergoing CAS-LA. On multivariable analysis, CAS-GA had a 2.3 times higher odds of in-hospital mortality compared with CAS-LA (OR, 2.52; 95% CI, 1.26-5.03), a 1.9 times the odds of MACE (OR, 1.87; 95% CI, 1.15-3.03), and a 2.3 times the odds of acute congestive heart failure (OR, 2.29; 95% CI, 1.26-4.15; all P < .05). In addition, these patients had a 43% higher odds of developing perioperative hypertension (OR, 1.43; 95% CI, 1.09-1.87; P = .01) and almost 2 times the odds of a prolonged length of stay (OR, 1.82; 95% CI, 1.41-2.35; P < .001). The adjusted odds of stroke, dysrhythmia and reperfusion syndrome were not significantly different between the two groups. Additional analysis using coarsened exact matching showed similar results. ConclusionsIn addition to the established increase risk of perioperative stroke/death with CAS compared with carotid endarterectomy, performing it under GA seems to be associated with increased cardiac complications, length of stay, and consequently hospitalization costs. Pending future data from prospective, randomized, controlled trials to validate our findings, there is evidence to suggest that it may be better to perform CAS under LA, especially in medically high-risk patients.

Use of Dual-Layered Stents in Endovascular Treatment of Extracranial Stenosis of the Internal Carotid Artery: Results of a Patient-Based Meta-Analysis of 4 Clinical Studies

ObjectivesThe aim of this study was to evaluate the clinical efficacy of dual-layered mesh-covered carotid stent systems (DLS) for carotid artery stenting (CAS). BackgroundThe need to minimize the risk for plaque debris prolapsing between stent struts following CAS has resulted in the development of DLS. Small clinical studies evaluating 2 available devices, Roadsaver and CGuard, have been recently published; none of these studies is sufficiently powered to test the role of common risk factors on the occurrence of stroke at 30 days post-CAS. MethodsA search was performed of multiple electronic databases for studies larger than 100 cases of CAS with DLS. Four single-arm prospective studies were identified, and individual patient data were collected. The primary endpoint was the occurrence of stroke at 30 days; secondary endpoints were technical and procedural success, periprocedural stroke, and in-hospital and 30-day rates of death. ResultsThe Roadsaver and CGuard stents were used in similar proportions, and technical success was achieved in all procedures (100% [n = 556]). There were 6 periprocedural strokes (1.08%; all minor). During 30-day follow-up, there was 1 death (0.17%) from myocardial infarction and 1 additional minor stroke (0.17%). The cumulative 30-day mortality rate was 0.17%, and the incidence of stroke at 30 days was 1.25%. No predictors of stroke at 30 days could be identified. ConclusionsThis meta-analysis suggests that DLS can be safely used for CAS, and their use minimizes the incremental risk related to symptomatic status and other risk factors.

Abstract TP121: National Patterns of Carotid Revascularization in the Pre- and Post- Crest Era

Background: The Carotid Revascularization Endarterectomy vs. Stenting Trial (CREST) showed greater safety of carotid artery stenting (CAS) in patients (pts) &lt;70 yo and endarterectomy (CEA) in &gt;70 yo. The aim of this study was to evaluate national patterns in CAS performance in pts &gt;70yo in the pre- (2007-2010) and post-CREST (2011-2013) era. Methods: Adults requiring CAS or CEA were identified from the 2007-2013 Nationwide Inpatient Sample (NIS) using International Classification of Disease (ICD-9) codes. We estimated the proportion of CAS performed in all age groups and used multivariate models adjusted for clinical and hospital factors to compare odds of receiving CAS in the pre- to post-CREST era. Results: We identified 839,357 weighted cases of CAS and CEA from the NIS. 15.7% of CAS and 8.4% of CEA were performed in symptomatic pts. CAS increased in all age groups over time (figure 1). Proportion of &gt;70yo receiving CAS increased from 11.9% in the pre- to 13.9% in the post-CREST era (p=0.004). In multivariate models, odds of receiving CAS as opposed to CEA increased by 15% in all pts &gt;70yo in the post-CREST compared to the pre-CREST period (OR 1.15, 95%CI 1.10-1.19, p&lt;0.001) including asymptomatic women (OR 1.10, 1.03-1.18). Congestive heart failure (OR 1.50, 95%CI 1.41-1.60), peripheral vascular disease (OR 1.41, 95%CI 1.34-1.48) and hospitalization in the Western region as opposed to the Northeast (OR 1.25, 95%CI 1.16-1.34) were associated with higher odds of CAS in pts&gt;70yo, while female sex (OR 0.92, 95%CI =0.89-0.97), smoking (OR 0.84, 95%CI 0.79-0.90) and weekend admission (OR 0.78, 95%CI 0.70-0.86) were negatively associated with odds of CAS. Conclusion: Rates of CAS increased in the post- compared to pre-CREST era in pts &gt;70yo including asymptomatic women. Despite the concerns of higher periprocedural complications with CAS in elderly pts, the results of CREST have not influenced clinical revascularization practice in pts &gt;70yo.

Abstract TMP21: Effect of Non-evidence Based Practices in Carotid Artery Stenting on Outcomes

Introduction: During the past decade, novel intra-procedural carotid artery stenting (CAS) techniques have emerged. Primary stenting, which forgoes the use of any angioplasty, and proximal embolic protection have been utilized in an attempt to mitigate perioperative complications. However, the effectiveness of such techniques remains controversial. We sought to assess the effect of primary stenting, proximal embolic protection, comorbidities, medications and other patient-level factors on outcomes of CAS in a multispecialty national database. Methods: We analyzed all CAS cases in the Vascular Quality Initiative (VQI) database from 2005 to 2015. Only patients with a follow up of ≥30 days were included. Propensity score matching was used to assess the effect of primary stenting on primary composite end-point outcome of stroke/transient ischemic attack (TIA)/death within 30 days of the procedure. A logistic regression model was constructed to determine the effect proximal protection and other characteristics had on 30-day stroke/TIA/death. Results: A total of 3,584 patients satisfied our selection criteria (mean age was 69.5±9.9 years; males 62%). Composite perioperative stroke/TIA/death rate was 9.7% (stroke 5.5%; TIA 2.4%; death 2.8%) and new myocardial infarction rate was 1.2%. Primary carotid stenting technique was used in 213(6.0%) patients, while proximal embolic protection was utilized in only 132(4.0%) patients. In a well-matched cohort of 211 primary stenting patients (total 422 patients): the 30-day stroke/TIA/death rate was almost double in the treated cohort (13.2% vs 7.1%, P&lt;0.05), while 30-day stroke/death rate was 4.6% higher in the primary stenting group (10.7% vs 6.1%, P=0.10). Proximal embolic protection had no significant effect on primary composite end-point (OR 0.68, P=NS), while P2Y12 antagonist use and a history of ipsilateral CEA each had approximately 30% reduction in risk of stroke/TIA/death (OR 0.71, P=0.03; OR 0.68, P=0.02). Conclusion: Primary carotid stenting carries a higher risk of perioperative stroke/TIA/death in CAS than traditional use of angioplasty. Proximal embolic protection has no significant effect on outcomes while P2Y12 antagonists and having a prior CEA reduce the chances of stroke/TIA/death.

Safety and Efficacy of A Single Embolic Protection Device-Stent Combo for Carotid Revascularization

AIM: Carotid artery stenting (CAS) yields similar safety and efficacy results in comparison to carotid endarterectomy. There is however a plethora of devices for CAS, and selection remains problematic. We hypothesized that operators proficient with a single embolic protection device-stent combination can use it effectively for most CAS cases. METHODS: We collected data on all patients undergoing CAS at our institutions, distinguishing patients undergoing revascularization with or without the Angioguard-Precise embolic protection-stent combo.The primary outcome was the risk ofmajor adverse events (MAE), i.e. the composite of death, stroke, transient ischemic attack, or myocardial infarction. RESULTS: A total of 532 patients were treated on 562 lesions. Angioguard-Precise could be used in 447 (84%) patients [471 (84%) lesions], whereas other approaches were used in 85 (16%) patients [91 (16%) lesions]. The groups were similar for most characteristics, but prior carotid revascularization, brachial/radial access, common carotid target lesion, and predilation were less common in the single combo group, whereas stenting and use of embolic protection were less frequent in the other cases (all p < 0.05). Procedural success was achieved in 462 (98%) of cases in the combo group and 89 (98%) in the other group (p=0.695). No significant differences in MAE were found in-hospital [respectively 7 (2%) vs 0, p = 0.604], at 30 days [8 (1.7%) vs 1 (1.2%), p = 1], or at long-term [44 (10%) vs 11 (13%), p = 0.294]. CONCLUSIONS: Operators proficient with a specific embolic protection-stent combination can use it with favorable results in the vast majority of patients.

Physician specialty and variation in carotid revascularization technique selected for Medicare patients

Carotid artery stenting (CAS) has become an alternative to carotid endarterectomy (CEA) for select patients with carotid atherosclerosis. We hypothesized that the choice of CAS vs CEA varies as a function of treating physician specialty, which would result in regional variation in the relative use of these treatment types. We used Medicare claims (2002-2010) to calculate annual rates of CAS and CEA and examined changes by procedure type over time. To assess regional preferences surrounding CAS, we calculated the proportion of revascularizations by CAS, across hospital referral regions, defined according to the Dartmouth Atlas of Healthcare. We then examined relationships between patient factors, physician specialty, and regional use of CAS. The annual number of all carotid revascularization procedures decreased by 30% from 2002 to 2010 (3.2 to 2.3 per 1000; P = .005). Whereas rates of CEA declined by 35% during these 8 years (3.0 to 1.9 per 1000; P < .001), CAS utilization increased by 5% during the same interval (0.30 to 0.32 per 1000; P = .014). Variation in utilization of carotid revascularization varied across the Unites States, with some regions performing as few as 0.7 carotid procedure per 1000 beneficiaries (Honolulu, Hawaii) and others performing nearly 8 times as many (5.3 per 1000 in Houma, La). Variation in procedure type (CEA vs CAS) was evident as well, as the proportion of carotid revascularization procedures that were constituted by CAS varied from 0% (Casper, Wyo, and Meridian, Miss) to 53% (Bend, Ore). The majority of CAS procedures were performed by cardiologists (49% of all CAS cases), who doubled their rates of CAS during the study period from 0.07 per 1000 in 2002 to 0.15 per 1000 in 2010. Variation in rates of carotid revascularization exists. Whereas rates of carotid revascularization have declined by more than 30% in recent years, utilization of CAS has increased. The proportion of all carotid revascularization procedures performed as CAS varies markedly by geographic region, and regions with the highest proportion of cardiologists perform the most CAS procedures. Evidence-based guidelines for carotid revascularization will require a multidisciplinary approach to ensure uniform adoption across specialties that care for patients with carotid artery disease.