Stent Retriever Research Articles

Abstract WP189: TIGER Study: Effectiveness and Safety of Tigertriever Are Maintained When Treating Large Clot Size

Introduction: Larger volume thrombi are associated with a lower probability of functional independence defined as a modified Rankin Score (mRS) ≤2 and a higher number of retrieval attempts. A subanalysis of the TIGER study data was performed in order to assess the effectiveness and safety of Tigertriever in small and large clot sizes. Methods: The TIGER study was a single arm, prospective, multi-center trial assessing the efficacy and safety of the Tigertriever, a radially-adjustable stent retriever, for LVO-related stroke. The trial enrolled 160 subjects, of which 150 had successful mTICI 2b-3 revascularization (94%) at end of all procedures. The interventionalists evaluated the clot length angiographically prior to the treatment, and analysis was performed to compare the Tigertriever performance in short clots with long clots. Results: Data is available from 135 (78 males) out of the 160 subjects enrolled in the study.The median clot length was 9mm with a range of 1-50mm. Subjects were divided into two subgroups: Group A; subjects with small clot length, ≤9mm (n=69) and group B, subjects with large clot length, >9mm (n=66). Baseline NIHSS was significantly smaller in group A compared to group B (16.9 vs.19, respectively, P=0.02). Median clot size in group A was 6.1mm and 16.5mm in group B. The mean number of passes with Tigertriever to achieve successful revascularization (mTICI 2b-3) was slightly higher in group B, but not statistically different (1.7 in group A vs. 2 in group B, P=0.07). First pass effect (63% vs. 50% NS), good clinical outcome (62% vs. 53% NS), sICH (1.4% vs. 3% NS) and ENT (Embolization to new territory 2.9% vs. 1.5% NS) were comparable in group A and group B, respectively. Conclusions: Despite the impaired neurological functioning as indicated by significantly higher baseline NIHSS in subjects admitted with larger clot length, Tigertriever efficacy and safety were maintained when treating these large clots compared to small clots.

Microfabricated Nitinol Stent Retrievers with a Micro-Patterned Surface.

Stent retrievers are medical devices that are designed to physically remove blood clots from within the blood vessels of the brain. This paper focuses on microfabricated nitinol (nickel-titanium alloy) stent retrievers, which feature micro-patterns on their surface to enhance the effectiveness of mechanical thrombectomy. A thick film of nitinol, which was 20 µm in thickness, was sputtered onto a substrate with a micro-patterned surface, using electroplated copper as the sacrificial layer. The nitinol film was released from the substrate and then thermally treated while folded into a cylindrical shape. In vitro experiments with pig blood clots demonstrated that the micro-patterns on the surface improved the efficacy of blood clot retrieval.

A case report of left circumflex stent infection and mycotic aneurysm: a rare but life-threatening complication of percutaneous coronary intervention

BackgroundCoronary stent infections are an uncommon but deadly complication of percutaneous coronary intervention. Mortality remains as high as 40–60% even with adequate treatment. We report such an interesting case of left circumflex stent (LCX) infection and mycotic aneurysm that was successfully managed with antibiotics and surgery.Case presentationA middle-aged man who underwent percutaneous coronary intervention (PCI) to the left circumflex artery four weeks prior was referred as a case of pyrexia of unknown origin, not responding to antibiotics, and colchicine started for suspected Dressler syndrome. Although the inflammatory markers were elevated, the results of the blood culture did not show any growth. Echocardiography showed a doubtful echogenic structure in the left atrioventricular groove and mild pericardial effusion, and a stent infection was suspected. PET scan showed focal metabolic activity in the region of the LCX stent, with metabolically active supraclavicular and paratracheal lymph nodes, and a coronary angiogram revealed an aneurysm arising distal to the stented LCX. A diagnosis of stent infection and associated mycotic aneurysm was made, and the patient underwent surgery which included aneurysm repair, stent retrieval, and coronary artery bypass graft (CABG) to the major and terminal OM. The postoperative course was uneventful, and the patient was discharged without complications.ConclusionsIt is important to investigate the possibility of coronary stent infection in individuals experiencing prolonged fever following PCI. PET scans and coronary angiograms can aid in diagnosis when echocardiograms are inconclusive. Adequate antibiotic therapy and timely surgery are crucial for successfully managing coronary stent infections.

Aspiration thrombectomy versus stent retriever thrombectomy as a first-line approach for cardiogenic cerebral embolism and cryptogenic stroke in large vessels of the anterior circulation.

This study aims to compare the clinical efficacy of aspiration thrombectomy and stent retriever thrombectomy as first-line approaches for anterior circulation large vessel cardiogenic cerebral embolism and cryptogenic stroke. This retrospective observational study included patients with anterior circulation large vessel cardiogenic cerebral embolism and cryptogenic stroke treated with endovascular therapy. Patients were grouped according to the first-line approach they received: aspiration thrombectomy or stent retriever thrombectomy. The primary outcome measure was the change in the National Institute of Health Stroke Scale (NIHSS) score from preoperative to immediate postoperative and from preoperative to discharge. Secondary indicators included the rate of favorable prognosis at discharge [Modified Rankin Scale (mRS) score ≤ 2], successful vessel recanalization rate [modified Treatment in Cerebral Ischemia (mTICI) score ≥ 2b], time from successful femoral artery puncture to successful vessel recanalization, and perioperative complications. The study included 127 cases, with 1 case withdrawal after enrollment due to a stroke of another determined cause, with 83 in the aspiration thrombectomy group and 43 cases in the stent retriever thrombectomy group. The change in NIHSS score from preoperative to immediate postoperative was 5 (1, 8) in the aspiration thrombectomy group and 1 (0, 4.5) in the stent retriever thrombectomy group. The change from preoperative to discharge was 8 (5, 12) in the aspiration thrombectomy group and 4 (0, 9) in the stent retriever thrombectomy group. The aspiration thrombectomy group exhibited significantly better prognosis rates and shorter time from successful femoral artery puncture to successful vessel recanalization. There were no significant differences between the two groups in terms of successful vessel recanalization rates and perioperative complications. As a first-line approach for anterior circulation large vessel cardiogenic cerebral embolism and cryptogenic stroke, aspiration thrombectomy leads to better improvement in neurological functional deficits and prognosis rates compared to stent retriever thrombectomy.

Common design and data elements reported in active mechanical thrombectomy trials focusing on distal medium vessel occlusions and minor strokes: a systematic review

BackgroundDistal medium vessel occlusions (DMVOs) and minor strokes represent emerging frontiers in mechanical thrombectomy (MT). Although several randomized clinical trials (RCTs) are underway, the design characteristics of these trials and...

Technique and impact on first pass effect primary results of the ASSIST global registry

BackgroundPatients treated with mechanical thrombectomy (MT) for acute ischemic strokes from large vessel occlusion (LVO) have better outcomes with effective reperfusion. However, it is unknown which technique leads to better...

Radially adjustable stent retriever for mechanical thrombectomy in acute ischemic stroke: Improved first-pass effect with rapid-inflation deflation technique.

Evidence for improved first-pass effect with the novel radially adjustable radio-opaque stent retriever Tigertriever is lacking. To compare improvement in first pass success with Tigertriever using two different techniques-rapid inflation deflation (RID) and suction thrombectomy (ST). Retrospective analysis of patients with acute ischemic stroke who underwent mechanical thrombectomy with Tigertriever at a single comprehensive stroke center. Thirty patients were included. Mean age was 72.8 years. Twelve patients (48%) experienced successful first passes with Tigertriever. Successful revascularization (modified thrombolysis in cerebral infarction (mTICI) 2b/3) was achieved in all (100%) patients who received RID or ST technique for thrombectomy. Good clinical outcome (modified Rankin score = 0-2) was noted in 40% (n = 10). Total mortality in the cohort was 8% (n = 2). RID and ST groups comprised of 10 and 15 patients, respectively. Five patients underwent MT with Tigertriever as a rescue device. No difference was noted in mean age (p = 0.27), gender (p = 0.29), location of occlusion (p = 0.46), and device used for first pass (p = 0.57). A 70% first-pass success rate in RID group and 37.5% in ST group was noticed (p = 0.06). Mean time from groin puncture to reperfusion (TICI 2b//3) was statistically similar (p = 0.29, RID: 19.9 min vs ST: 25 min). Both groups noted a 100% complete recanalization rate. The rate of mortality between the two groups were not statistically different (p = 0.46). The preliminary first-pass success rates of RID technique with Tigertriever compared to ST technique, are encouraging. Longitudinal studies with longer follow up are needed to elucidate the smaller learning curve with this device.

Disability-free outcomes after mechanical thrombectomy: A systematic review and meta-analysis of the randomized controlled trials.

The modified Rankin Scale (mRS) score of ≤2 (functional independence) has been the most common primary endpoint of modern mechanical thrombectomy (MT) trials. However, unlike mRS 0-1, mRS score of 2 indicates disability. An important proportion of the mRS 2 patients are home dependent and report a significant decrease in their quality of life. To investigate excellent outcome (mRS 0-1) rates after MT. We systematically searched Ovid MEDLINE, Ovid EMBASE, Cochrane Central Register of Controlled Trials, Scopus, and Web of Science databases. Randomized controlled trials (RCTs) investigating the role of modern MT in acute ischemic stroke were screened. Posterior circulation and large-core infarct trials were excluded from the study. The data regarding excellent outcomes (mRS: 0-1), functional independence (mRS: 0-2), and reperfusion were collected. Twenty-two RCTs comprising 5692 patients were included in the meta-analysis. The overall mRS 0-1 rate was 31.24% (95% CI = 26.95-36.2). The rate of successful reperfusion was 81.8% (95% CI = 77.93-85.86). MT achieved significantly higher rates of mRS 0-1 compared to standard care alone (OR = 2.04; 95% CI = 1.64-2.55; P-value < 0.001), with no heterogeneity detected among studies (I2= 0%; P-value = 0.52). The direct MT and MT plus intravenous thrombolytic treatment groups' excellent outcome rates were comparable (OR = 0.98; 95% CI = 0.82-1.18; P-value = 0.863). Also, aspiration and stent retriever thrombectomy techniques provided similar excellent outcome rates (OR = 0.76; 95% CI = 0.55-1.05; P-value = 0.141). Our results prove the additional benefit of MT over standard care, using a stricter definition for favorable functional outcome. Nearly one-third of patients presenting with large artery occlusion and treated with MT had no disability at 90 days. While this is remarkable, our results also indicate that reperfusion alone is often not enough to prevent disability and underline the need for better neuroprotection strategies.

Postmarket Surveillance of Neuroendovascular Devices

Endovascular devices have catalyzed a global industry for advanced technologies such as flow diverters and stent retrievers. Though adoption of these devices has skyrocketed over the past 30 years, the regulatory landscape for real‐world monitoring is constantly under revision. Postmarket surveillance is an area of Medical Device Regulation that monitors how devices perform in the real world after regulatory approval. This area of research is underdeveloped globally, with most surveillance relying on passive adverse event data collection from health care systems. The US Food and Drug Administration has not yet established a comprehensive postmarket surveillance strategy for neuroendovascular devices. Postmarket clinical surveillance data are rare; only 4 mandated 522 postmarket neuroendovascular trials exist, and 4 of 14 endovascular registries have published results per ClinicalTrials.gov. The European Union 2017 Medical Device Regulation describes a comprehensive regulatory strategy to address postmarket surveillance, yet it has faced difficult implementation due to resource constraints and concerns such as increased costs and reliance on foreign devices and regulators. More than 50% of manufacturers are planning portfolio reductions, with 33% of the devices from these manufacturers planned for discontinuation. As of April 2022, &gt;85% of 500 000+ previously certified devices were without new certification. In this article, we describe the current regulatory landscape for postmarket surveillance and support the need for a comprehensive, cost‐efficient postmarket strategy for neurovascular devices while proposing several solutions and considerations. An effective postmarket strategy has numerous benefits, such as promoting patient safety, expanding real‐world data collection, and increased efficiency for approving future devices.

Impact of atherosclerotic etiology on technical and clinical outcomes of mechanical thrombectomy with a stent retriever: subanalysis of the Japan Trevo Registry

BackgroundThe safety and effectiveness of stent retriever use for patients with acute large vessel occlusion (LVO) due to intracranial atherosclerotic disease (ICAD) is not well established. We investigated the differences...

Thrombectomy With the pRESET vs Solitaire Stent Retrievers as First-Line Large Vessel Occlusion Stroke Treatment

Stent retriever-based thrombectomy is highly beneficial in large vessel occlusion (LVO) strokes. Many stent retriever designs are currently available, but comparison of these technologies in well-conducted studies is lacking. To determine whether thrombectomy for LVO stroke with the pRESET stent retriever is noninferior to treatment with the Solitaire stent retriever. This study was a multicenter, prospective, randomized, controlled, open-label, adaptive, noninferiority trial with blinded primary end point evaluation. Between October 2019 and February 2022, multicenter participation occurred across 19 research hospitals and/or universities in the US and 5 in Germany. Patients with LVO stroke were enrolled and included up to 8 hours after symptom onset. Patients underwent 1:1 randomization to thrombectomy with the pRESET or Solitaire stent retriever. The primary outcome was the difference in the rate of 90-day functional independence across the 2 devices, using a -12.5% noninferiority margin for the lower bound of the 1-sided 95% CI of the difference between pRESET and Solitaire retrievers. Of 340 randomized patients, 170 (50.0%) were female, and the median (IQR) age was 73.0 (64.0-82.0) years. The study procedure was completed in 322 of the 340 randomized patients. The primary end point of 90-day functional independence was achieved by 95 patients (54.9%; 95% CI, 48.7-61.1) in the pRESET group and in 96 (57.5%; 95% CI, 51.2-63.8) in the Solitaire group (absolute difference, -2.57%; 95% CI, -11.42 to 6.28). As the lower bound of the 95% CI was greater than -12.5%, the pRESET retriever was deemed noninferior to the Solitaire retriever. The noninferiority of pRESET over Solitaire was also observed in the secondary clinical end point (90-day shift in modified Rankin Scale score) and in both angiographic end points (Expanded Treatment in Cerebral Infarction [eTICI] score of 2b50 or greater within 3 passes: 146 of 173 [84.4%] vs 149 of 167 [89.2%]; absolute difference, -4.83%; 95% CI, -10.84 to 1.19; eTICI of 2c or greater following the first pass: 76 of 173 [43.7%] vs 74 of 167 [44.3%]; absolute difference, -0.63%; 95% CI, -9.48 to 8.21). Symptomatic intracranial hemorrhage occurred in 0 patients in the pRESET group and 2 (1.2%) in the Solitaire group. Mortality occurred in 25 (14.5%) in the pRESET group and in 24 (14.4%) in the Solitaire group at 90 days. Findings of the per-protocol and as-treated analyses were in concordance with findings of the intention-to-treat analysis. In this study, among patients with LVO stroke, thrombectomy with the pRESET stent retriever was noninferior to thrombectomy with the Solitaire stent retriever. Findings suggest that pRESET offers a safe and effective option for flow restoration and disability reduction in patients with LVO stroke.

Safety and Efficacy of Aspiration Catheter CAT6 and 5 Fr Navien in the Endovascular Treatment of Acute Ischemic Stroke.

Mechanical thrombectomy has become a key treatment option for acute ischemic stroke. This study compared the safety and efficacy of aspiration catheter CAT6 and 5 Fr Navien. Thrombectomy was performed in103 patients with the acute internal carotid artery, middle cerebral artery M1 or M2 occlusions, including the CAT6 group (n=53 with stent retriever and CAT6 aspiration) and the 5 Fr Navien group (n=50 with stent retriever and 5 Fr Navien aspiration) at the Advanced Stroke Center. Overall, an aspiration catheter placement success rate was achieved in 93.2% of cases, 52 (98.11%) for CAT6, and 44 (88.00%) for 5 Fr Navien ( P =0.042). Overall, 17 cases (16.51%) required additional guidewire rates, 5.66% for CAT6, and 13.592% for 5 Fr Navien ( P =0.002). First-pass success rate (FPSR) was achieved in 38.84% of cases overall, a rate that did not differ significantly between catheters: 45.28% for CAT6; 32.00% for 5 Fr Navien ( P =0.167). Final thrombolysis in cerebral infarction 2b or 3 reperfusion was achieved in 91.26% of cases overall, 51 (96.23%) for CAT6, and 43 (86%) for 5 Fr Navien ( P =0.066). The participants had a mean number of passes for the index thrombus of 1.956 and a median procedure time of 65.82±21.8 minutes. There was no significant difference found in 90-day good outcome (mean 42.7%, modified Rankin Score 0 to 2) and 90-day mortality (17%) between CAT6 and 5 Fr Navien. Aspiration catheter placement success rate and first-pass success rate seemed to be higher for CAT6 and, moreover, the rate of additional guidewires was lower.

A porcine model of thoracic aortic aneurysms created with a retrievable drug infusion stent graft mirrors human aneurysm pathophysiology

ObjectiveAneurysm pathophysiology remains poorly understood, in part from the disparity of murine models with human physiology and the requirement for invasive aortic exposure to apply agents used to create aneurysm models. A retrievable drug infusion stent graft (RDIS) was developed to isolate the aortic wall intraluminally for drug exposure. We hypothesized that an RDIS could deliver aneurysm-promoting enzymes to create a porcine model of thoracic aneurysms without major surgical exposure. MethodsRetrievable nitinol stent graft frames were designed with an isolated drug delivery chamber, covered with polytetrafluoroethylene, and connected to a delivery wire with a drug infusion catheter installed to the outer chamber. Institutional Animal Care and Use Committee-approved Yorkshire pigs (n = 5) underwent percutaneous access of the femoral artery, baseline aortogram and stent placement in the thoracic aorta followed by 30-minute exposure to a cocktail of elastase, collagenase, and trypsin. After aspiration of excess drug, stent retrieval, and femoral artery repair, animals were recovered, with angiograms at 1 and 4 weeks followed by explant. Histological analysis, in situ zymography, and multiplex cytokine assays were performed. ResultsThe RDIS isolated a segment of anterior aorta angiographically, while the center lumen preserved distal perfusion during drug treatment (baseline femoral mean arterial pressure, 70 ± 14 mm Hg; after RDIS, 75 ± 12; P = .55). Endovascular induction of thoracic aneurysms did not require prior mechanical injury and animals revealed no evidence of toxicity. Within 1 week, significant aneurysmal growth was observed in all five animals (1.4 ± 0.1 cm baseline to 2.9 ± 0.7 cm; P = .002) and only within the treated region of the aorta. Aneurysms persisted out to 4 weeks. Aneurysm histology demonstrated loss of elastin and collagen that was otherwise preserved in untreated aorta. Proinflammatory cytokines and increased matrix metalloproteinase activity were increased significantly within the aneurysm. ConclusionsAn RDIS achieves isolated drug delivery while preserving distal perfusion to achieve an endovascular porcine model of thoracic aneurysms without major surgery. This model may have value for surgical training, device testing, and to better understand aneurysm pathogenesis. Most important, although the RDIS was used to simulate aortic pathology, this tool offers intriguing horizons for focused therapeutic drug delivery directly to aneurysms and, more broadly, focused locoregional drug delivery to vessels and vascular beds.

A Comprehensive Prediction Model for Futile Recanalization in AIS Patients Post-Endovascular Therapy: Integrating Clinical, Imaging, and No-Reflow Biomarkers.

Our study aimed to construct a predictive model for identifying instances of futile recanalization in patients with anterior circulation occlusion acute ischemic stroke (AIS) who achieved complete reperfusion following endovascular therapy. We included 173 AIS patients who attained complete reperfusion, as indicated by a Modified Thrombolysis in Cerebral Infarction (mTICI) scale score of 3. Our approach involved a thorough analysis of clinical factors, imaging biomarkers, and potential no-reflow biomarkers through both univariate and multivariate analyses to identify predictors of futile recanalization. The comprehensive model includes clinical factors such as age, presence of diabetes, admission NIHSS score, and the number of stent retriever passes; imaging biomarkers like poor collaterals; and potential no-reflow biomarkers, notably disrupted blood-brain barrier (OR 4.321, 95% CI 1.794-10.405; p = 0.001), neutrophil-to-lymphocyte ratio (NLR; OR 1.095, 95% CI 1.009-1.188; p = 0.030), and D-dimer (OR 1.134, 95% CI 1.017-1.266; p = 0.024). The model demonstrated high predictive accuracy, with a C-index of 0.901 (95% CI 0.855-0.947) and 0.911 (95% CI 0.863-0.954) in the original and bootstrapping validation samples, respectively. Notably, the comprehensive model showed significantly improved predictive performance over models that did not include no-reflow biomarkers, evidenced by an integrated discrimination improvement of 8.86% (95% CI 4.34%-13.39%; p < 0.001) and a categorized reclassification improvement of 18.38% (95% CI 3.53%-33.23%; p = 0.015). This model, which leverages the potential of no-reflow biomarkers, could be especially beneficial in healthcare settings with limited resources. It provides a valuable tool for predicting futile recanalization, thereby informing clinical decision-making. Future research could explore further refinements to this model and its application in diverse clinical settings.

Star-PCL shape memory polymer (SMP) scaffolds with tunable transition temperatures for enhanced utility.

Thermoresponsive shape memory polymers (SMPs) prepared from UV-curable poly(ε-caprolactone) (PCL) macromers have the potential to create self-fitting bone scaffolds, self-expanding vaginal stents, and other shape-shifting devices. To ensure tissue safety during deployment, the shape actuation temperature (i.e., the melt transition temperature or Tm of PCL) must be reduced from ∼55 °C that is observed for scaffolds prepared from linear-PCL-DA (Mn ∼ 10 kg mol-1). Moreover, increasing the rate of biodegradation would be advantageous, facilitating bone tissue healing and potentially eliminating the need for stent retrieval. Herein, a series of six UV-curable PCL macromers were prepared with linear or 4-arm star architectures and with Mns of 10, 7.5, and 5 kg mol-1, and subsequently fabricated into six porous scaffold compositions (10k, 7.5k, 5k, 10k★, 7.5k★, and 5k★) via solvent casting particulate leaching (SCPL). Scaffolds produced from star-PCL-tetraacrylate (star-PCL-TA) macromers produced pronounced reductions in Tm with decreased Mnversus those formed with the corresponding linear-PCL-diacrylate (linear-PCL-DA) macromers. Scaffolds were produced with the desired reduced Tm profiles: 37 °C < Tm < 55 °C (self-fitting bone scaffold), and Tm ≤ 37 °C (self-expanding stent). As macromer Mn decreased, crosslink density increased while % crystallinity decreased, particularly for scaffolds prepared from star-PCL-TA macromers. While shape memory behavior was retained and radial expansion pressure increased, this imparted a reduction in modulus but with an increase in the rate of degradation.

Cost-Effectiveness of a Direct-Aspiration First-Pass Technique versus Stent Retriever in Mechanical Thrombectomy

A direct-aspiration first-pass technique (ADAPT) in mechanical thrombectomy has been described in recent studies as an efficacious strategy compared with using a stent retriever (SR). We sought to evaluate for cost differences of ADAPT technique versus SR as an initial approach. We conducted a retrospective analysis of consecutive patients with mechanical thrombectomy at our institution between 2022 and 2023. Patients were grouped into ADAPT with/without SR as a rescue strategy and SR as an initial approach with allowance of concomitant aspiration. Direct cost data (consumables) were obtained. Baseline demographics, stroke metrics, procedure outcomes and cost, and last follow-up outcomes in modified Rankin Scale were compared between 2 groups. Fifty-six patients were included. Thirty-seven (66.1%) underwent ADAPT, with 11 (29.7%) eventually requiring an SR. Mean age was 64.8 years. The average National Institutes of Health Stroke Scale score was 13.2 in the ADAPT group and 14.0 in the SR group (P= 0.68), with a similar proportion of tissue plasminogen activator (P= 0.53), site of occlusion (P= 0.66), and tandem occlusion (P= 0.69) between the groups. Recanalization was achieved in 94.6% of all patients, with an average of 1.9 passes, 89.3% being TICI 2B or above, with no differences between the 2 groups. Significantly lower cost (P < 0.01) was observed in ADAPT ($14,243.4) compared with SR ($19,003.6). Average follow-up duration was 180.2 days, with mortality of 23.2%. At last follow-up, 55.4% remained functionally independent (modified Rankin Scale score <3) with no difference (P= 0.56) between the ADAPT (59.5%) and SR (47.4%) groups. Outcomes were comparable between the ADAPT and SR groups. ADAPT reduced procedural consumables cost by approximately $5000 (25%), even if stent retrievers were allowed to be used for rescue. Establishing ADPAT as initial approach may bring significant direct cost savings while obtaining similar outcomes.

A scoping review of cerebral reperfusion therapies in childhood and adolescence with arterial ischemic stroke

AbstractBackgroundManagement of pediatric stroke is challenging because of the paucity of data supporting the efficacy of interventions. This scoping review details the treatments available for the acute phase of stroke in pediatric patients with arterial ischemic stroke.Summary of ReviewOverall, 68 relevant articles were published between 2001 and 2023. The primary study included 48 case reports (n = 48). Eleven articles reported the use of intravenous thrombolysis (IVT) with alteplase, eight used intra‐arterial (IA) alteplase, and 52 reported mechanical thrombectomy (MT). IVT was administered to 195 patients with a median of 5.5 h of stroke onset, and only four (2.0%) had intracranial hemorrhage after alteplase treatment. Of the 11 articles, nine used 0.9 mg/kg IVT administered as a 10% bolus, with the remaining 90% administered over one hour, and one study used 0.54 mg/kg. IA was performed in 17 patients with a median of 5.05 h of stroke onset, and three individuals (17.6%) had intracranial hemorrhage. Of the eight reports that document IA, two used 0.9 mg/kg; one each used 0.16 mg/kg, 0.1 mg/kg, 0.6 mg/kg, 100 mg/day, and 10 mg/day; and one article documented the use of urokinase 750 000 IU. MT was used in 434 and 215 individuals in a previous systematic review, with a median of 11.82 h of stroke onset, and only 2.9% had intracranial hemorrhage after the treatment. Stent retrievers were used in 33 reports (63.5%) and aspiration retrievers were mentioned in 15 articles (28.8%). Overall, the outcomes ranged from complete to moderate recovery for all modalities.ConclusionsIVT and MT are safer than IA; however, despite the lack of clinical trials, all modalities seem effective in improving clinical recovery. To guide clinical practice and determine better intervention modalities, clinicians should note the key messages from this review, such as using magnetic resonance imaging in the acute phase and identifying key risk factors and presenting symptoms.

Rescue Strategy for Hemorrhagic Complication During Mechanical Thrombectomy and the Clinical Outcome.

Hemorrhagic complications occasionally occur during mechanical thrombectomy and may lead to catastrophic outcomes. Therefore, remedial strategies require careful investigation. Herein, we aimed to evaluate a cohort of patients who experienced hemorrhage during endovascular procedures, the rescue methods used, and outcomes observed. This prospective study included patients who had hemorrhagic complications observed on digital subtraction angiography (DSA) during mechanical thrombectomy, between October 2017 and October 2022, at a high-volume stroke center. Functional outcomes were assessed using the modified Rankin scale (mRS) score at a 90-day follow-up. The primary outcomes were favorable outcomes (mRS score: 0-2 points) and mortality rates. The secondary outcomes were rescue therapy success rates, according to extravasation observed on the final DSA, recanalization status, and causes of hemorrhage. From October 2017 to October 2022, 1537 patients with stroke received emergency endovascular therapy, and 1147 patients completed a 90-day follow-up. Hemorrhage was observed in 33 (2.1%) patients in the process of endovascular interventions. Eighteen (54.5%) cases of hemorrhage were caused by microwire or microcatheter perforation. Mechanical stretching of the vessel during stent retriever withdrawal resulted in 8 (24.2%) cases of hemorrhage. Nine (27.3%) instances of hemorrhage stopped after the reversal of heparin administration and introduction of blood pressure control measures. Further endovascular rescue treatment was performed in 11 patients. Intracranial inflation of the balloon for tamponade stopped 10 hemorrhages, and 1 patient underwent additional coil embolization. Fifteen (45.5%) patients died within 90 days after the procedure. Three (9.1%) patients recovered functional independence (mRS score: 0-2 points) within 90 days. Hemorrhage during mechanical thrombectomy is a rare but severe complication of acute ischemic stroke with high mortality and disability rates. Intracranial inflation of a balloon for tamponade can effectively stop extravasation. This paper described haemorrhagic events characterised by contrast extravasation in the procedure of mechanical thrombectomy due to various causes. Although this complication is rare, patients showed a high mortality and disability rate. There are limited reports available. We found self-limiting haemorrhage had a rather benign prognosis and balloon tamponade could effectively stop the extravasation and might reduce the death rate within 90d. The methods we adopted could be applied in the clinical practice and help neuro-interventionist cope with this complication more promptly and effectively.

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

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

Effectiveness of the preventive administration of vasoactive amines in counterbalancing significant patient blood pressure drops following nimodipine administration during mechanical thrombectomy procedures

Background Focal vasospasm (FV) of the occluded vessel can occur during the endovascular treatment of acute ischemic stroke (AIS). Nimodipine is commonly used to treat vasospasm and can play a role in distinguishing it from artery narrowing due to iatrogenic dissection or residual clot. However, nimodipine administration can result in arterial hypotension and subsequent enlargement of the ischemic core. Objective To assess the efficacy of preventive and continuous vasoactive amine infusion to counterbalance nimodipine-induced hypotension. Methods We reviewed data from a prospective registry of patients treated for AIS between January 2019 and January 2022 who were administered nimodipine. All patients were equipped with an arterial cannula for invasive blood pressure measurement and given vasoactive amines preemptively before general anesthesia and throughout the procedure. Data obtained from invasive monitoring of mean arterial blood pressure (MABP) in a time-lapse of 25 min before and after nimodipine administration were analyzed. Results MABP significantly decreased after nimodipine administration but remained within the recommended range (81.79 ± 0.49 mmHg). Nimodipine was effective in reducing FV caused by stent retriever passage in 76.3% of cases. Furthermore, it proved valuable in diagnosing iatrogenic dissection (9.2%), residual clot (10.5%), or intracranial stenosis (4%). Conclusions Infusion of vasoactive amines effectively counteracted the intraarterial nimodipine effect, thus avoiding frank arterial hypotension during endovascular treatment. Nimodipine has been useful in differentiating the diagnosis of FV resulting from mechanical thrombectomy and other potential causes, such as iatrogenic dissection or residual clot.