Double Stent Retriever (SR) Technique: A Novel Mechanical Thrombectomy Technique to Facilitate the Device-Clot Interaction for Refractory Acute Cerebral Large Vessel Occlusions

Double Stent Retriever Technique for Mechanical Thrombectomy: A Systematic Review and Meta-Analysis

BACKGROUND

Mechanical thrombectomy using a double stent retriever technique has recently been described for the treatment of acute ischemic stroke, but its efficacy and safety are not well-established.

PURPOSE

The aim of this systematic review and meta-analysis was to evaluate reports of the use of a double stent retriever technique during the endovascular treatment of patients with ischemic stroke.

DATA SOURCES

The PubMed, EMBASE, Web of Science, and Scopus databases were searched to identify all studies (clinical trials, cohort series, and case reports) investigating the utility of a double stent retriever technique for the treatment of stroke. The study is reported in accordance with PRISMA 2020 guidelines and was prospectively registered in PROSPERO (CRD42023482691).

STUDY SELECTION

Seventeen studies involving a total of 128 patients with large-vessel occlusions predominantly in the anterior circulation (93.0%) were identified.

DATA ANALYSIS

Outcomes of interest were the prevalence of successful recanalization (modified TICI ≥2b) and a first-pass effect following the double stent retriever technique as well as complications such as iatrogenic dissections and SAH. Data were pooled using a random effects model.

DATA SYNTHESIS

The double stent retriever technique was used as a rescue strategy in occlusions refractory to conventional endovascular treatment in 68.7% (88/128) of patients and as a first-line strategy in 31.3% (40/128) of patients. The double stent retriever technique achieved an overall final modified TICI ≥2b in 92.6% cases, with a first-pass effect of 76.6%. The complication rate remained low, with 0.37% dissection and 1.56% SAH.

LIMITATIONS

Limitations of the study include the following: 1) a large number of case reports or small series, 2) a meta-analysis of proportions with no statistical comparison with a control group, and 3) the lack of access to patient-level data.

CONCLUSIONS

Our findings suggest that double stent retriever thrombectomy may be safe and associated with good recanalization outcomes, but prospective comparative studies are needed to determine which patients may benefit from this endovascular procedure.

Could emergency admission plasma D-dimer level predict first pass effect of stent retriever thrombectomy in acute ischemic stroke?

BACKGROUND

Evidence on plasma biomarkers to identify first pass effect (FPE) in patients with acute ischemic stroke (AIS) with large vessel occlusion (LVO) treated with thrombectomy is limited.

PURPOSE

To evaluate whether plasma D-dimer could predict FPE.

MATERIAL AND METHODS

Consecutive patients with LVO who underwent first-line stent retriever thrombectomy at our center between January 2018 and August 2021 were enrolled. Patients were classified into the FPE (modified Thrombolysis in Cerebral Infarction [mTICI] ≥2c) group or non-FPE (mTICI 0-2b) group based on angiographic outcomes. Logistic regression analysis was performed to determine the predictors of FPE. The overall ability of D-dimer levels in predicting FPE was evaluated using receiver operating characteristic (ROC) curves.

RESULTS

In total, 313 patients were included; 88 (28.1%) patients achieved FPE. Compared to those with non-FPE, patients with FPE had more diabetes mellitus history, lower D-dimer levels, higher clot burden score, a higher proportion of M1 middle cerebral artery, and a higher proportion of main stem occlusion pattern (P <0.05). After adjusting for potential variables, D-dimer levels (OR=0.81, 95% CI=0.52-0.96), clot burden score (OR=1.76, 95% CI=1.38-2.87), and main stem occlusion pattern (OR=1.85, 95% CI=1.19-2.62) remained independently associated with FPE. Based on the ROC analysis, the D-dimer as a predictor for predicting FPE presented with a specificity of 79%, a negative predictive value of 87%, and an area under the curve of 0.761.

CONCLUSION

Low emergency admission plasma D-dimer level is an independent predictor of FPE in patients with AIS treated with stent retriever thrombectomy.

Mechanical Thrombectomy Using Double Stent Retriever Technique for Acute Ischemic Stroke Following Embolism From the Pulmonary Vein Stump After Left Upper Lobectomy: A Case Report

Acute ischemic stroke (AIS) following pulmonary lobectomy, which is traditionally attributed to air embolism and atrial fibrillation (AF), may occur after thrombus formation in the pulmonary vein stump (PVS). Herein, we document the mechanical thrombectomy (MT) of a carotid bifurcation occlusion post-left upper lobectomy (LUL) to manage AIS. A 76-year-old male with a history of diabetes, dyslipidemia, and a treated dural arteriovenous fistula at the transverse sigmoid junction, with no history of AF, successfully underwent LUL for a pulmonary tumor. The patient independently walked on postoperative day 1. He developed right hemiparesis and total aphasia on the morning of the second day after surgery, which was discovered by the nursing staff. A magnetic resonance imaging (MRI) confirmed an occlusion of the left common carotid artery (CCA). Tissue plasminogen activator (t-PA) was not administered owing to recent surgery. An urgent MT using multiple MT techniques carried out 90 minutes after the discovery of symptoms only achieved partial recanalization. Subsequently, a double stent retriever technique (DSRT) addressed the occlusion in the common and cervical internal carotid artery (ICA). Following this, a T occlusion was encountered, which was addressed with a combined approach using a single stent retriever (SR), achieving a thrombolysis in cerebral infarction (TICI) grade 2b result. However, postoperative aphasia and severe right hemiparesis remained. Postoperative imaging showed a significant left cerebral hemisphere infarction and a thrombus in the PVS. Oral edoxaban was administered, and PVS thrombosis did not recur. The patient was transferred to a rehabilitation facility 190 days post-embolization with a modified Rankin Scale score of 4. In this report, we demonstrate the challenging case of the DSRT in addressing AIS after LUL, which led to the formation of a massive thrombus and occlusion of the carotid artery, as revealed by the PVS. This case emphasizes the importance of collaborative efforts between thoracic surgeons and all staff involved in stroke care in managing such complex scenarios.

A review of mechanical thrombectomy techniques for acute ischemic stroke

Mechanical thrombectomy is established as standard of care in the management of acute ischemic stroke due to large vessel occlusion and evidence-based guidelines for mechanical thrombectomy have been defined. As research continues to further expand the eligibility criteria for thrombectomy and the number of thrombectomy procedures increase worldwide, there is also growing focus on innovation of thrombectomy devices, procedural techniques, and related outcomes. Thrombectomy primarily involves use of stent retrievers and distal aspiration techniques, but variations and different combinations of techniques have been reported. As this is a rapidly evolving area in stroke management, there is debate as to which, if any, of these techniques leads to improved clinical outcomes over another and there is a lack of data comparing them. In this review, currently published and distinct techniques of mechanical thrombectomy are described methodically along with illustrations to aid in understanding the subtle differences between the techniques. The perceived benefits of each variation are discussed.

Double stent retriever technique for rescue recanalization in refractory large vessel occlusions

Acute ischemic stroke patients with large vessel occlusion (LVO) involving bifurcation usually have a difficult and high clot burden. By using conventional technique often resulting in a reduction in the possibility of successful recanalization. The double stent retriever technique can be considered for rescue recanalization. We reported a case of refractory terminal left internal carotid occlusion that was treated using double stent retriever technique. Two microcatheter were advanced across the occlusion were one to the superior branch of middle cerebral artery and another was on inferior branch. Both stent retrievers were pulled back together and complete recanalization was achieved. This technique were reported in some case series to be effective and based on our initial experience using this technique it seems the expansion improved after deployment of the second stent retriever and it traps the clot within its stent struts, to facilitate clot retrieval. Therefore, double stent retriever technique can be one of the choices for rescue recanalization in refractory clot occlusion and it may potentially help other clinicians in similar situations.

Microcatheter tracking in thrombectomy procedures: A finite-element simulation study

BACKGROUND AND OBJECTIVE

Mechanical thrombectomy is a minimally invasive procedure that aims at removing the occluding thrombus from the vasculature of acute ischemic stroke patients. Thrombectomy success and failure can be studied using in-silico thrombectomy models. Such models require realistic modeling steps to be effective. We here present a new approach to model microcatheter tracking during thrombectomy.

METHODS

For 3 patient-specific vessel geometries, we performed finite-element simulations of the microcatheter tracking (1) following the vessel centerline (centerline method) and (2) as a one-step insertion simulation, where the microcatheter tip was advanced along the vessel centerline while its body was free to interact with the vessel wall (tip-dragging method). Qualitative validation of the two tracking methods was performed with the patient's digital subtraction angiography (DSA) images. In addition, we compared simulated thrombectomy outcomes (successful vs unsuccessful thrombus retrieval) and maximum principal stresses on the thrombus between the centerline and tip-dragging method.

RESULTS

Qualitative comparison with the DSA images showed that the tip-dragging method more realistically resembles the patient-specific microcatheter-tracking scenario, where the microcatheter approaches the vessel walls. Although the simulated thrombectomy outcomes were similar in terms of thrombus retrieval, the thrombus stress fields (and the associated fragmentation of the thrombus) were strongly different between the two methods, with local differences in the maximum principal stress curves up to 84%.

CONCLUSIONS

Microcatheter positioning with respect to the vessel affects the stress fields of the thrombus during retrieval, and therefore, may influence thrombus fragmentation and retrieval in-silico thrombectomy.

Access to and application of recanalizing therapies for severe acute ischemic stroke caused by large vessel occlusion

BACKGROUND

Groundbreaking study results since 2014 have dramatically changed the therapeutic options in acute therapy for severe ischemic stroke caused by large vessel occlusion (LVO). The scientifically proven advances in stroke imaging and thrombectomy techniques have allowed to offer the optimal version or combination of best medical and interventional therapy to the selected patient, yielding favorable or even excellent clinical outcomes within time windows unheard of before. The provision of the best possible individual therapy has become a guideline-based gold standard, but remains a great challenge. With geographic, regional, cultural, economic and resource differences worldwide, optimal local solutions have to be strived for.

AIM

This standard operation procedure (SOP) is aimed to give a suggestion of how to give patients access to and apply modern recanalizing therapy for acute ischemic stroke caused by LVO.

METHOD

The SOP was developed based on current guidelines, the evidence from the most recent trials and the experience of authors who have been involved in the above-named development at different levels.

RESULTS

This SOP is meant to be a comprehensive, yet not too detailed template to allow for freedom in local adaption. It comprises all relevant stages in providing care to the patient with severe ischemic stroke such as suspicion and alarm, prehospital acute measures, recognition and grading, transport, emergency room workup, selective cerebral imaging, differential treatment by recanalizing therapies (intravenous thrombolysis, endovascular stroke treatmet, or combined), complications, stroke unit and neurocritical care.

CONCLUSIONS

The challenge of giving patients access to and applying recanalizing therapies in severe ischemic stroke may be facilitated by a systematic, SOP-based approach adapted to local settings.

Comprehensive classifications for the endovascular recanalization of vertebral artery stump syndrome

Background

and purpose: To share our single-center vertebral artery stump syndrome (VASS) treatment experience and assess the role of comprehensive classification based on anatomic development, proximal conditions, and distal conditions (PAD).

Materials and methods

Data were retrospectively collected from patients who underwent endovascular thrombectomy (EVT) at the Stroke Center of the First Hospital of Jilin University between January 2016 and December 2021. Among patients with acute ischemic stroke in the posterior circulation, those with acute occlusion of the intracranial arteries and occlusion at the origin of the vertebral artery confirmed by digital subtraction angiography were selected. The clinical data were summarized and analyzed.

Results

Fifteen patients with VASS were enrolled in the study. The overall success rate of surgical recanalization was 80%. The successful proximal recanalization rate was 70.6%, and the recanalization rates for P1, P2, P3, and P4 were 100%, 71.4%, 50%, and 66.67%, respectively. The mean operation times for the A1 and A2 types were 124 and 120 ​min, respectively. The successful distal recanalization rate was 91.7%, and the recanalization rates for types D1, D2, D3, and D4 were 100%, 83.3%, 100%, and 100%, respectively. Five patients experienced perioperative complications (incidence rate: 33.3%). Distal embolism occurred in three patients (incidence rate: 20%). No dissection or subarachnoid hemorrhage occurred in any patient.

Conclusion

EVT is a technically feasible treatment for VASS, and comprehensive PAD classification can, to a certain extent, help initially estimate the difficulty of surgery and provide guidance for interventional procedures.

Bifurcation occlusions and endovascular treatment outcome in acute ischemic stroke

BACKGROUND

A thrombus in the M1 segment of the middle cerebral artery (MCA) can occlude this main stem only or extend into the M1-M2 bifurcation. The occlusion pattern may affect endovascular treatment (EVT) success, as a bifurcated thrombus may be more prone to fragmentation during retrieval.

OBJECTIVE

To investigate whether bifurcated thrombus patterns are associated with EVT procedural and clinical outcomes.

METHODS

Occlusion patterns of MCA thrombi on CT angiography from MR CLEAN Registry patients were classified into three groups: main stem occlusion, bifurcation occlusion extending into one M2 branch, and bifurcation occlusion extending into both M2 branches. Procedural parameters, procedural outcomes (reperfusion grade and embolization to new territory), and clinical outcomes (24-48 hour National Institutes of Health Stroke Scale [NIHSS_FU] score, change in NIHSS scores between 24 and 48 hours and baseline ∆ [NIHSS], and 90-day modified Rankin Scale [mRS] scores) were compared between occlusion patterns.

RESULTS

We identified 1023 patients with an MCA occlusion of whom 370 (36%) had a main stem occlusion, 151 (15%) a single branch, and 502 (49%) a double branch bifurcation occlusion. There were no statistically significant differences in retrieval method, procedure time, number of retrieval attempts, reperfusion grade, and embolization to new territory between occlusion patterns. Patients with main stem occlusions had lower NIHSS_FU scores than patients with single (7 vs 11, p=0.01) or double branch occlusions (7 vs 9, p=0.04). However, there were no statistically significant differences in ∆ NIHSS or in 90-day mRS scores.

CONCLUSIONS

In our population, EVT procedural and long-term clinical outcomes were similar for MCA bifurcation occlusions and MCA main stem occlusions.

Mechanical Thrombectomy for Acute Common Carotid Artery Occlusion

Mechanical thrombectomy (MT) is the standard treatment for acute large occlusion of the cerebral artery. Evidence for the success of this procedure was based on the treatment of patients with internal carotid artery and middle cerebral artery thrombi. There are a few reports on thrombi extending to the common carotid artery (CCA). We document our endovascular procedure and the clinical outcome in seven consecutive patients who underwent MT for CCA thrombi between September 2016 and April 2021. Their mean National Institutes of Health Stroke Scale score was 20.0 (range, 9-30), and the mean diffusion-weighted imaging Alberta Stroke Program Early Computed Tomography Score on magnetic resonance images was 8.7 (range, 7-10). In six patients, MT of the CCA occlusion was successful, and the mean puncture-to-reperfusion time was 84 minutes (range, 39-211 minutes). In five patients, successful reperfusion was obtained. The mean total pass number was 4.1 (range, 2-7). Due to large thrombi, we performed balloon guide catheter (BGC) occlusion in three patients. Sheath occlusion occurred in two, and thrombus migration into the femoral artery around the sheath was observed in two patients. The mean modified Rankin Scale score 3 months post-stroke was 3.6 (range, 2-5). When the removal of a large CCA thrombus is attempted in a single step, catheter and sheath occlusion may occur, and this increases the risk for critical systemic artery occlusion. Therefore, we suggest that MT be combined with the BGC technique and propose the use of a large aspiration catheter to decrease the volume of the thrombus.

Distal Embolization in Relation to Radiological Thrombus Characteristics, Treatment Details, and Functional Outcome

BACKGROUND

Distal embolization (DE) is a common complication of endovascular treatment (EVT). We investigated the association of radiological thrombus characteristics and treatment details with DE.

METHODS

Patients with thin-slice (≤2.5 mm) baseline noncontrast computed tomography and computed tomography angiography from the ESCAPE-NA1 trial (Efficacy and Safety of Nerinetide for the Treatment of Acute Ischemic Stroke) were included. Thrombus annotation was performed manually on coregistered scans by experienced readers. We assessed thrombus location, distance from internal carotid artery terminus, length, perviousness, absolute attenuation, and hyperdense artery sign. In addition, we evaluated balloon guide catheter use during EVT, first-line EVT approach, the number of thrombectomy passes, and prior intravenous thrombolysis administration. DE was defined as the occurrence of emboli distal to the target artery or in new territories during EVT. The association between thrombus characteristics, treatment details, and DE was evaluated using descriptive statistics and multivariable mixed-effects logistic regression, resulting in adjusted odds ratios (aOR) with 95% CI. Interaction between IVT and radiological thrombus characteristics was assessed by adding interaction terms in separate models.

RESULTS

In total, 496 out of 1105 (44.9%) ESCAPE-NA1 patients were included. DE was detected in 251 out of 496 patients (50.6%). Patients with DE had longer thrombi (median, 28.5 [interquartile range, 20.8-42.3] mm versus 24.4 [interquartile range, 17.1-32.4] mm; P<0.01). There were no statistically significant differences in the other thrombus characteristics. Factors associated with DE were thrombus length (aOR, 1.02 [95% CI, 1.01-1.04]), balloon guide catheter use (aOR, 0.49 [95% CI, 0.29-0.85]), and number of passes (aOR, 1.24 [95% CI, 1.04-1.47]). In patients with hyperdense artery sign, IVT was associated with reduced odds of DE (aOR, 0.55 [95% CI, 0.31-0.97]), P for interaction=0.04.

CONCLUSIONS

DE was associated with longer thrombi, no balloon guide catheter use, and more EVT passes. IVT was associated with a reduced risk of DE in patients with hyperdense artery sign. These findings may support treatment decisions on IVT and EVT approaches.

Endovascular Treatment of Tandem Atherosclerotic Cervical Internal Carotid Artery Occlusion in the Setting of Acute Ischemic Stroke

BACKGROUND

Among tandem occlusions, atherosclerotic cervical internal carotid artery occlusion (ACICAO) can be technically challenging and associated with its unique complications. We evaluated our experience with endovascular treatment (EVT) of ACICAO in the setting of acute ischemic stroke.

METHODS

In total, 154 consecutive patients who underwent EVT for acute anterior circulation stroke at our institute were retrospectively reviewed. Patients with tandem ACICAO were analyzed in this study. Procedures, recanalization rates, complications, and prognoses were evaluated.

RESULTS

Ten patients (6%) of all 154 patients had ACICAO. In nine (90%) of the 10 patients, cervical lesions were successfully crossed and intervened upon. Four patients underwent stenting and five underwent angioplasty alone, followed by intracranial procedure. Eight patients (80%) achieved successful recanalization following mechanical thrombectomy for intracranial occlusion. However, one patient had massive subarachnoid hemorrhage during the procedure and another patient developed massive intracranial hemorrhage after EVT, both after stenting. Four of the five patients who initially underwent angioplasty alone subsequently underwent staged endarterectomy or stenting for residual stenosis on or after the next day. The single patient in whom the cervical lesion could not be crossed and another with reocclusion after EVT underwent a rescue bypass procedure due to persistent ischemic symptoms. After 90 days, four patients (40%) were functionally independent (modified Rankin scale score 0-2).

CONCLUSIONS

Our experience suggests that EVT for ACICAO is technically feasible; however, it involves the potential risk of several significant complications. To avoid serious hemorrhagic complications, cervical lesions may be better treated with angioplasty alone first.

Acute internal carotid artery occlusion due to dissection of the paraclinoid segment: Diagnostic usefulness of angiographic findings during stent retriever deployment

Intracranial artery dissection is an uncommon but possible cause of ischemic stroke, and is usually diagnosed based on imaging findings such as mural hematoma and dissection flap. However, it is challenging to recognize the underlying dissection in cases of acute large vessel occlusion. In this report, we present a case of acute internal carotid artery occlusion, in which the underlying dissection of the paraclinoid segment was found during the thrombectomy procedure. Two thrombectomy procedures failed to recanalize the acute internal carotid artery occlusion without removing any clot. Angiography performed during a Trevo stent retriever deployment in the first pass showed obscure contrast defects in the stent strut with temporary flow restoration. In the next pass, the appearance of the contrast defects changed and a parallel linear contrast appeared on the outside of the vessel wall. These angiographic findings were identified as mural hematoma and dissection flap, indicating dissection of the paraclinoid as the cause of the occlusion. During antiplatelet loading and preparation of a dedicated intracranial stent, the Trevo stent retriever was left deployed again at the occlusion site to maintain the blood flow. After permanent stenting with an Enterprise stent, angiography revealed complete recanalization. The patient recovered fully after the procedure. In the present case, stent retriever deployment revealed the hallmarks of dissection on angiography, such as mural hematoma, dissection flap, and temporal morphological changes, by restoring the blood flow temporarily. Such angiographic findings can provide useful information on the occlusion characteristics and real-time feedback for optimal treatment strategy.

First Experience with the Nimbus Stentretriever

Purpose

To share our first experience with the Nimbus stentretriever, a multizone device designed to assist neurointerventionalists in handling fibrin-rich clots in endovascular stroke treatment.

Methods

We retrospectively analyzed the data of patients who were treated with the Nimbus stentretriever at our high-volume stroke center between May 2021 and May 2022. We evaluated the number of passes before Nimbus was used, the number of passes with nimbus, as well as the recanalization success before and after Nimbus according to the modified treatment in cerebral ischemia (mTICI) scale. Also, patient characteristics, procedural times and clinical outcomes were documented.

Results

A total of 21 consecutive patients were included in the study. An mTICI 2b/3 could be achieved in 76.2% and mTICI 2c/3 could be achieved in 57.1%. The mean number of passes was 3.4 before the use of Nimbus, 2.2 with Nimbus, and 5.4 for all passes with and without Nimbus and 4 occlusions (19.0%) were successfully recanalized with direct aspiration after the use of Nimbus. We observed seven subarachnoid hemorrhages (33.3%) and two cases of vasospasm.

Conclusion

In our series, the use of Nimbus resulted in successful recanalization in half of the patients after otherwise unsuccessful thrombectomy maneuvers; therefore, it should be considered as a rescue option if the maneuver with conventional stent retrievers was unsuccessful.

Mechanical Thrombectomy with Tandem Double Stent Retriever in Combination with Intermediate Catheter Aspiration for Refractory Severe Hemorrhagic Cerebral Venous Sinus Thrombosis

OBJECTIVE

We aimed to describe the initial experience of mechanical thrombectomy using tandem double stent retrievers combined with intermediate catheter aspiration to treat refractory severe hemorrhagic (SH)-cerebral venous sinus thrombosis (CVST).

METHODS

All refractory SH-CVST patients treated with mechanical thrombectomy using tandem double stent retriever (SR) combined with intermediate catheter aspiration (MT-TDSA) in our institution were retrospectively reviewed. MT-TDSA is a technique that fully engages the clot with double SRs and retrieves the clot using a double SR in combination with aspiration from an intermediate catheter. Demographics, clinical manifestation, medical history, the location of the occluded venous sinus, intraoperative details, procedure-related complications, and modified Rankin Scale (1, 6, 12 months postoperatively) were collected and analyzed.

RESULTS

Fourteen patients (median age, 43 years) with refractory SH-CVST were treated with MT-TDSA between January 2016 and January 2020. Ten of 14 (71.4%) had a successful intraoperative recanalization rate (>90%) using MT-TDSA. No procedure-related complications occurred. Eleven patients had good clinical outcomes (modified Rankin Scale score 0-2 at 12 months postoperatively).

CONCLUSIONS

MT-TDSA for refractory SH-CVST might improve clot-capturing ability and remove blood clots from cerebral venous sinuses effectively and safely, achieving good clinical outcomes.

Crossing double stent retriever technique for refractory terminal internal carotid artery occlusion

Mechanical thrombectomy is highly effective for the recovery of acute ischemic stroke with large vessel occlusion. However, refractory occlusions are still encountered despite the use of currently available devices. In this article, we present a case of refractory terminal internal carotid artery occlusion treated with the "crossing double stent retriever technique." Two thrombectomy procedures with the combined technique using a stent retriever and aspiration catheter failed to recanalize the terminal internal carotid artery occlusion that involved the dominant anterior cerebral artery. We then applied the crossing double stent retriever technique as a rescue technique. Two microcatheters were advanced across the occlusion: one to the anterior cerebral artery and the other to the middle cerebral artery. First, a Trevo NXT 4 mm stent retriever was deployed from the anterior cerebral artery. Next, an additional Trevo NXT 4 mm stent retriever was deployed from the middle cerebral artery, and full immediate restoration of flow was achieved on angiography. Intraprocedural radiological images showed that the 2 microcatheters traversed different pathways, and the 2 stent retrievers completely covered the entire vessel with apparent in-stent clot sign. Both stent retrievers were then pulled back together, and a hard clot was retrieved. Subsequent angiography revealed complete recanalization. The crossing double stent retriever technique seems an effective rescue technique for treating refractory terminal internal carotid artery occlusion, especially with the anatomical feature of branching of the dominant anterior cerebral artery. This technique can facilitate the device-clot-vessel interaction by engaging the clot via 2 different device pathways.

Mechanical Thrombectomy Using Kissing Y-Solitaire as a Rescue Treatment for Refractory Acute Popliteal and Infrapopliteal Occlusion in Elderly Patients

Six patients were included to retrospectively review the preliminary efficacy and safety of mechanical thrombectomy using kissing Y-Solitaire as a rescue treatment. This technique was performed following failed single Solitaire thrombectomy in 5 patients (5/6), and the remaining patient (1/6) underwent unsuccessful AngioJet thrombectomy (Boston Scientific, Marlborough, Massachusetts). The ranges of the target vessel clot length and diameter were 4.9-6.9 mm and 27-38 mm, respectively. Technical success was achieved in all patients (6/6). They (6/6) had notable acute limb ischemia (ALI) symptom relief after 1 or 2 passes of retrieval, and clinical success was achieved in all patients (6/6). No complications were observed other than reversible vasospasm in 1 patient (1/6). Amputation or death did not occur. Mechanical revascularization with the use of kissing Y-Solitaire seems to be a potentially rapid, safe, and effective modality for selected patients with refractory short-segment occlusion of ALI secondary to popliteal and infrapopliteal arteries.

Iatrogenic intracranial vessel dissection during mechanical thrombectomy rescued by emergent stenting: 2 case reports

Intracranial vessel dissection is a procedural complication associated with endovascular treatment. However, there have been few reports on its potential causes and management during mechanical thrombectomy. In approximately 250 cases of mechanical thrombectomy over the past 5 years at our institution, iatrogenic intracranial dissection occurred in 2 patients (0.8%). In this report, we described these 2 cases that were rescued through emergent stenting. Mechanical thrombectomy, using both a stent retriever and an aspiration catheter, was performed for acute middle cerebral artery M2 occlusion in Patient 1 (a 69-year-old man) and for distal M1 occlusion in Patient 2 (an 83-year-old woman). In both cases, recanalization was achieved with the procedure, but irregular stenosis developed at the initially nonoccluded, but mildly arteriosclerotic, M1, after recanalization. During the thrombectomy procedure, the aspiration catheter sifted up to the arteriosclerotic M1. In both cases, the lesions were considered vessel dissection, due to a shift of the aspiration catheter tip into the arteriosclerotic vessel wall. Repeated percutaneous angiography with antithrombotic therapy failed to improve the lesions and to maintain the antegrade blood flow. Finally, lesions in each patient were successfully rescued through the use of emergent stenting. A drug-eluting stent for coronary use was deployed in Patient 1, and an Enterprise stent was applied in Patient 2. Inadvertent shift of the aspiration catheter into arteriosclerotic vessels can cause a serious intracranial vessel dissection. When performing mechanical thrombectomy, intracranial stents need to be available as rescue treatment devices to manage refractory iatrogenic intracranial vessel dissection.

Initial experience with the CatchView thrombectomy device for acute ischemic stroke

BACKGROUND

We report our initial experience with the CatchView (CV) thrombectomy device in patients with acute ischemic stroke (AIS).

METHODS

A retrospective analysis of 53 of 284 AIS patients (mean age 66.6±14.8 years, range 37-94) treated with a CV device between January 2019 and February 2020 was performed. The baseline characteristics (gender, age, comorbidities, National Institutes of Health Stroke Scale (NIHSS) score, intravenous tissue plasminogen activator (IV-tPA) administration, and occlusion localization) of these subjects were recorded. Modified Thrombolysis in Cerebral Ischemia (mTICI) scores of 2b and 3 were considered to indicate successful recanalization, and subjects with a modified Rankin Scale score of ≤2 on day 90 was considered a good clinical outcomes.

RESULTS

The mean NIHSS score was 12.3±3. Successful recanalization was achieved in 45 subjects (84.90%), and the rate of good clinical outcomes on day 90 was 43.39%. The secondary distal embolus rate was 5.66%. Symptomatic hemorrhage was observed in 3.77% of the subjects, and the mortality rate was 13.2%.

CONCLUSIONS

Mechanical thrombectomy devices include a wide array of endovascular tools for removing clots in AIS patients. In terms of successful recanalization and good clinical outcomes on day 90, our initial experience with the CV devices was encouraging.