Using the Casper Stent in Carotid Angioplasty: A Single Center Experience

Objectives To establish the success rate in endovascular internal carotid artery (ICA) stenosis recanalization using the double-layer stent Casper-RX (Microvention, Inc 35 Enterprise, Aliso Viejo, California, United States of America) and to identify the main comorbidities in individuals with ICA stenosis, morphological characteristics of the stenosis, diagnostic methods, intraoperative complications, as well as morbidity and mortality within 30 days of the surgical procedure. Materials and Methods Retrospective analysis of 116 patients undergoing ICA angioplasty with a degree of stenosis ≥ 70% using Casper-RX stenting who underwent this procedure from April 2015 to December 2019. Results Technical success was achieved in 99.1% of the patients. Three of them had postprocedural complications: one transient ischemic attack (TIA) and two puncture site hematomas. A cerebral protection filter was not used in only two procedures, as these consisted of dissection of the carotid. There was satisfactory recanalization and adequate accommodation of the stents in the previously stenosed arteries, with no restenosis in 99.4% of the cases. Conclusion The endovascular treatment of extracranial carotid stenoses using the Casper-RX stent showed good applicability and efficacy. Although only two cases of thromboembolic complications occurred during the procedure, further investigation and studies on the effectiveness of this new device are needed.

Stenting of ultraembolic hazardous carotid stenotic lesions using the technique of triple antiembolic protection

Objective ‒ to develop a technique of triple antiembolic protection with the simultaneous use of proximal antiembolic protection systems, distal antiembolic filters and two-layer micromesh carotid stents for carotid stenting of ultraembolic hazardous carotid stenosis. Evaluate its effectiveness and safety.Materials and methods. Since 2016, 23 carotid stenting of ultraembolic hazardous carotid stenoses has been performed using the technique of triple antiembolic protection (proximal antiembolic protection systems, distal antiembolic filters and two-layer micromesh carotid stents). All patients had symptomic stenosis: transient ischemic attacks in a certain carotid pool (n = 7), ischemic strokes (n = 16). The age of patients was from 57 to 84 years. Men prevailed among patients (n = 15). Postoperative follow-up included magnetic resonance imaging (MRI) of the brain on the first or second day after surgery with T2*, FLAIR and DWI sequences to determine the presence of «fresh» embolic ischemic foci and to exclude hemorrhagic complications. After 6 months, a control clinical examination, computed tomography or MRI of the brain, ultrasound angioscanning of the main arteries of the head were performed.Results. In all patients the patency of the carotid arteries was completely restored, and in the early postoperative period, no clinical signs of recurrent ischemic brain damage were detected in any of the cases. No signs of plaque prolapse through the stent were detected in any case. A significant amount of atheromatous debris was in 11 cases when aspirated on an external filter. In 3 cases, emboli were also detected in the distal protection filter. This fact indicates that the joint use of distal and proximal antiembolic systems reliably protects against the risk of embolism in such cases. According to MRI on the 1st or 2nd day there were no signs of «fresh» subclinical embolic ischemic foci, as well as hemorrhage. In 20 patients who underwent a follow-up examination, no signs of restenosis in the stent were recorded in any case, as well as repeated ischemic strokes. In 7 cases where the plaque had an ulcer, the ulcer resolved under the stent. Three patients are expected for a follow-up examination. According to the remote survey, these patients do not have new ischemic brain lesions. The effectiveness of the technique of triple antiembolic protection for the treatment of patients with subtotal ultraembolic hazardous carotid stenosis is indicated by the absence of clinical and neuroradiological signs of recurrent ischemic lesions.Conclusions. The technique of triple antiembolic protection for the treatment of patients with subtotal ultraembolic hazardous carotid stenoses is safe and highly effective. It is the improvement of carotid stenting results in this most dangerous group that gives reason to think about revealing the advantages of carotid stenting over carotid endarterectomy in general.

Defining carotid near-occlusion with full collapse: a pooled analysis

Purpose Create a new definition of near-occlusion with full collapse to predicting recurrent stroke. Methods Pooled analysis of two studies. Patients with symptomatic ≥ 50% carotid stenoses were included. Outcome was preoperative recurrent ipsilateral ischemic stroke or retinal artery occlusion within 28 days of presenting event. We analyzed several artery diameters on computed tomography angiography and stenosis velocity on ultrasound. Results A total of 430 patients with symptomatic ≥ 50% carotid stenosis were included, 27% had near-occlusion. By traditional definition, 27% with full collapse and 11% without full collapse reached the outcome (p = 0.047). Distal internal carotid artery (ICA) diameter, ICA ratio, and ICA-to-external carotid artery ratio were associated with the outcome. Best new definition of full collapse was distal ICA diameter ≤ 2.0 mm and/or ICA ratio ≤ 0.42. With this new definition, 36% with full collapse and 4% without full collapse reached the outcome (p < 0.001). Conclusions Defining near-occlusion with full collapse as distal ICA diameter ≤ 2.0 mm and/or ICA ratio ≤ 0.42 seems to yield better prognostic discrimination than the traditional appearance-based definition. This novel definition can be used in prognostic and treatment studies of near-occlusion with full collapse.

Failed carotid artery stenting followed by successful surgical intervention: Case report

A 56-year-old female patient with significant carotid stenoses with circumferential plaques, causing localized vascular narrowing, was inappropriately indicated for carotid artery stenting. After placement of a distal embolic protection device in the left internal carotid artery, a stent was inserted; however, it could not be fully deployed due to the rigid, severely calcified vascular walls. The various endovascular attempts to recapture the protection device were futile and, eventually, led to fracture of the guidewire of the device and it remained entrapped together with the stent. Emergency carotid arteriotomy with extirpation of the stent and embolic protection device via carotid thromboendarterectomy was performed. In conclusion, the proper patient selection for carotid artery stenting is of utmost importance.

Ultrasound detection of cerebral microembolism in carotid stenoses: progress and perspective (A review of the literature)

The review summarizes available information regarding the method of Transcranial doppler sonography (TCD) usage to record microembolism in patients with carotid artery stenosis, search for information was carried out in literature 1997–2020 (PUBMED, MEDLINE).History overview of TCD with embolodetection implementation is presented, as well as ways of its technical and methodological improvement. Evidence-based studies of the method clinical relevance in atherosclerotic carotid stenoses and their surgical treatment are outlined. Observation results of the intraoperative cerebral embolization during carotid endarterectomy and carotid artery stenting are presented along with comparison of TCD-embolodetection data, neuroimaging and clinical outcomes. Individual centres and multicenter study ACES data on prognostic value of registration of embolic signals in asymptomatic carotid stenosis, risk assessment of vascular events in diffe-rent groups of patients and in varying degrees of stenosis of the vessel lumen was analyzed. The role of embolodetection in predicting repeated cerebrovascular disorders in symptomatic carotid stenosis and its importance for monitoring antiplatelet therapy is set out (multicenter study CARESS). The evidence of the reliability of TCD embolodetection as tool for verificarion of at-risk patients with carotid stenosis who may benefit ftom surgical treatment is presented.Recent advances in ultrasound and other imaging techniques for assessing unstable plague are outlined along with prospects for the use of TCD monitoting for cerebrovascular disorders forecasting.

Atherosclerotic ICA stenosis coinciding with ICA asymmetry associated with Circle of Willis variations can mimic near-occlusion

Differentiating carotid near-occlusion (tight atherosclerotic stenosis causing distal artery size reduction) from conventional stenosis is the first step when grading carotid stenoses with NASCET method. The internal carotid artery (ICA) can be asymmetrically associated with Circle of Willis variations. When such ICA asymmetry coincides with stenosis, it may mimic near-occlusion. We studied ICA anatomical variant prevalence in 4042 consecutive CTA exams from all indications, 53 excluded due to carotid occlusion, 814 with any ≥ 50% steno-occlusive disease intra- or extracranially, 3228 without. Of the 3989 included cases, 568 (14%) had ICA asymmetry, of which 335 (59%) were from associated with Circle of Willis variations. Of 3228 patients without ≥ 50% stenosis or other steno-occlusive disease intra- and extracranially; 257 (8.0%) demonstrated ICA asymmetry associated with Circle of Willis variations, equally common among sexes and age unrelated and most frequently attributed to an ipsilateral A1 hypoplasia/aplasia, less often attributed to large contralateral posterior communicating artery. As ICA asymmetry associated with Circle of Willis variations are common, caution should be exercised diagnosing near-occlusion on asymmetry alone.

Possible involvement of pericytes in intraplaque hemorrhage of carotid artery stenosis

OBJECTIVEIntraplaque hemorrhage (IPH) is most often caused by the rupture of neovessels; however, the factors of intraplaque neovessel vulnerability remain unclear. In this study, the authors focused on pericytes and aimed to investigate the relationship between IPH and pericytes.METHODSThe authors retrospectively analyzed the medical records of all patients with carotid artery stenoses who had undergone carotid endarterectomy at their hospitals between August 2008 and March 2016. Patients with carotid plaques that could be evaluated histopathologically were eligible for study inclusion. Intraplaque hemorrhage was analyzed using glycophorin A staining, and patients were divided into the following 2 groups based on the extent of granular staining: high IPH (positive staining area > 10%) and low IPH (positive staining area ≤ 10%). In addition, intraplaque neovessels were immunohistochemically evaluated using antibodies to CD34 as an endothelial cell marker or antibodies to NG2 and CD146 as pericyte markers. The relationship between IPH and pathology for intraplaque neovessels was investigated.RESULTSSeventy of 126 consecutive carotid stenoses were excluded due to the lack of a specimen for histopathological evaluation; therefore, 53 patients with 56 carotid artery stenoses were eligible for study inclusion. Among the 56 stenoses, 37 lesions had high IPH and 19 had low IPH. The number of CD34-positive neovessels was equivalent between the two groups. However, the densities of NG2- and CD146-positive neovessels were significantly lower in the high IPH group than in the low IPH group (5.7 ± 0.5 vs. 17.1 ± 2.4, p < 0.0001; 6.6 ± 0.8 vs. 18.4 ± 2.5, p < 0.0001, respectively).CONCLUSIONSPlaques with high IPH are associated with fewer pericytes in the intraplaque neovessels. This finding may help in the development of novel therapeutic strategies targeting pericytes.

A case of tandem stenoses at the proximal common and internal carotid arteries treated with transbrachial stenting: a case report

The transfemoral approach is a common technique for carotid artery stenting. However, it has the risk of distal embolism when stenting for a stenosis of the proximal common carotid artery because of poor stability of the guiding catheter resulting in difficulty in setting the embolic protection device prior to stenting. We present a novel therapeutic approach and technique for the treatment of tandem carotid stenoses including the proximal common carotid artery. A 63-year-old man presented with double stenoses at the common carotid artery and internal carotid artery. We used a transbrachial sheath guide that had a 6 Fr (2.24 mm, 0.088 inch) internal diameter and was 90 cm long, and was specifically designed for direct cannulation to the common carotid artery, like a modified Simmons catheter. Because the sheath guide positioned in the aortic arch made it possible to introduce safely the embolic protection device distal to the internal carotid artery stenosis without touching the plaque at the stenosis with no use of any coaxial catheters or guidewires, carotid artery stenting for tandem stenoses could be successfully carried out. The postoperative course was uneventful. In carotid artery stenting, especially for stenosis of the proximal common carotid artery, the sheath guide designed for transbrachial carotid cannulation was useful in stenting the tandem carotid stenoses.