M1 Occlusion Research Articles

Mechanical Thrombectomy for Treatment of Acute Cerebral Infarction due to Distal Medium Vessel Occlusions: A Retrospective Cohort Study.

Mechanical thrombectomy (MT) is standard of care for acute cerebral infarction (ACI) due to large vessel occlusions. However, its clinical efficacy in patients with ACI due to distal medium vessel occlusions (DMVOs) remains unclear. This study evaluates the efficacy and safety of MT in patients with ACI due to DMVOs. Totally, 306 patients with ACI at a very early stage were assigned into DMVOs-MT, M1-MT, and DMVOs-intravenous thrombolysis (IVT) groups. These groups were compared regarding baseline data, recanalization rate, location of vessel occlusions, number of thrombectomy, first-pass recanalization, mRS scores, NIHSS scores, 90-day mRS scores, incidence of adverse events, and mortality. Risk factors for poor prognosis of patients with DMVOs following MT were analyzed. DMVOs-MT and M1-MT groups showed comparable first-pass recanalization rates, recanalization rates, and NIHSS score reduction ratios, with marked differences in location of vessel occlusions. Versus DMVOs-IVT, DMVOs-MT had increased differences between pre- and post-treatment NIHSS scores and between pre-treatment NIHSS scores and NIHSS scores at discharge and elevated NIHSS reduction ratios. The poor prognosis rate of DMVOs-MT group was insignificantly different from that of M1-MT group but lower than that of DMVOs-IVT group. Adverse events and mortality incidences were comparable among the three groups. Diabetes, first-pass recanalization, and pre-treatment NIHSS scores were independent risk factors for poor prognosis in DMVO patients after MT. MT is as effective and safe in patients with DMVOs as in patients with M1 occlusions. In patients with DMVOs, MT has higher efficacy and safety than IVT.

Middle cerebral artery hypodense dot sign in iatrogenic air embolism.

Air embolism is a rare cause of stroke, usually associated with medical procedures, with gastrointestinal endoscopy rarely implicated. Here, we present a case of a patient who experienced cerebral air embolism post-gastroscopy, presenting with aphasia and right hemiparesis due to left M2 occlusion with spontaneous and complete recovery. CT scan revealed a hypodense defect in the left Sylvian fissure, representing a "hypodense dot sign" suggestive of an air embolism. The hypodense MCA sign, previously described in fat embolism cases, could also indicate air embolism, supporting prompt diagnosis and proper intervention.

Acute middle cerebral artery occlusion due to a small internal carotid aneurysm cavity with blood stagnation: illustrative case.

In cerebral large vessel occlusion, even when an aneurysm is close to the target vessel, if the aneurysm is relatively small and angiography shows no thrombus within the aneurysm, it is difficult to identify the aneurysm as the embolic source. A 67-year-old man with a history of two left-sided cerebral infarctions developed a small left-sided cerebral infarction. On hospital day 3, he developed a left M2 occlusion and underwent thrombectomy with retraction of a stent retriever into an aspiration catheter at the proximal end of the thrombus. A red thrombus was retrieved, and M2 recanalization was successfully achieved. Angiography revealed a large partially thrombotic aneurysm with a small cavity with blood stagnation in the left cervical internal carotid artery, which was considered the embolic source. Stent-assisted coil embolization was performed on the aneurysm, and no recurrent cerebral infarction was observed after embolization. In cerebral large vessel occlusion, an aneurysm cavity with blood stagnation may be the embolic source. Using an aspiration catheter alone or retracting a stent retriever into an aspiration catheter could be a useful technique and help to avoid interference between the aneurysm and the stent retriever. https://thejns.org/doi/10.3171/CASE24406.

Effect of occlusion site on the effectiveness and safety of endovascular thrombectomy for large ischemic cores: A cohort study.

Recent clinical trials have shown that patients with large ischemic cores have better outcomes with endovascular thrombectomy (EVT) compared with standard medical treatment (SMT) alone.We aim to assess whether the relationship between EVT and improvements in clinical outcomes varies depending on the location of the occlusive sites. This study is a subgroup analysis conducted within a prospective, nationwide, multi-center registry. The cohort included patients with acute large vessel occlusion in the anterior circulation and an Alberta Stroke Program Early Computed Tomography Score of 0 to 5 within 24 hours from last known well. We utilized the adjusted common odds ratio for a shift toward better outcome on the modified Rankin Scale after EVT compared with SMT alone as the primary outcome. Safety outcomes included symptomatic intracranial hemorrhage (sICH). A total of 745 patients with large ischemic cores were included: 272(36.5%) with internal carotid artery occlusion, 392(52.6%) with M1 segment of the middle cerebral artery occlusion, and 81(11.0%) with M2 segment of the middle cerebral artery occlusion. The adjusted common odds ratios were as follows: 1.98 (95% CI, 1.01-3.89) for ICA occlusions, 2.09 (95% CI, 1.35-3.23) for M1 occlusions, and 1.13 (95% CI, 0.43-2.94) for M2 occlusions. There was no significant treatment-by-occlusion site interaction observed (P=0.69). However, the incidence of sICH was significantly greater in all groups receiving EVT than in those receiving SMT alone. Additionally, we observed that the secondary outcomes and subgroup analyses were generally consistent with the main outcomes. In this study, we found that patients with internal carotid artery and M1 occlusion demonstrated a better outcome with EVT, while the benefit for patients with M2 occlusion remains uncertain.

Subacute in-stent thrombosis after carotid artery stenting in a patient with gene polymorphisms associated with aspirin and clopidogrel resistance: a case report

BackgroundCarotid artery stenting (CAS) is a key treatment option for moderate to severe carotid artery stenosis. Carotid stent thrombosis (CST), a rare complication of CAS, has gained significant attention because of its catastrophic nature. More evidences are needed to guide the diagnosis and treatment of CST.Case presentationThis study reports a rare case of sub-acute CST following CAS in a 50-year-old male patient who had experienced repeated cerebrovascular events on the premise of taking antiplatelet drugs. He also suffered an occlusion of the left middle cerebral artery (MCA) in the M2 segment, likely caused by an embolus detached from the stent thrombus. The cause of CST in this patient was presumed to be dual antiplatelet resistance (AR), as indicated by genetic testing. After treated with guide catheter-directed thrombolysis, thrombus aspiration, and a second round of thrombolysis, his in-stent thrombus was basically cleared. His M2 occlusion was resolved by mechanical thrombectomy using the Solitaire FR/Stent with Intermediate Catheter Assisting technique. The patient recovered well after replacement of antiplatelet drugs, and no new thromboembolic event occurred during the 13-month follow-up period.ConclusionsThe occurrence rate of AR-related CST may be underestimated as the cause of majority CST cases remains unclear. Implementation of genetic test for aspirin and clopidogrel resistance may be helpful to find the possible cause of CST and to avoid future repeated cerebrovascular events by replacement of antiplatelet drugs.

Is the hemoglobin, albumin, lymphocyte, and platelet (HALP) score a novel biomarker for predicting mortality in patients with middle cerebral artery infarctions undergoing mechanical thrombectomy?

BackgroundThe hemoglobin, albumin, lymphocyte, and platelet (HALP) score, easily calculated parameter, indicating systemic inflammation and nutritional status IntroductionIn this study, we used the HALP score in patients with acute ischemic stroke (AIS) undergoing mechanical thrombectomy (MT) to predict 90-day mortality. Method122 patients with AIS who underwent either MT or MT and tissue plasminogen activator (tPA) for middle cerebral artery (MCA) M1 occlusion. The HALP score was calculated, demographic data, modified Rankin Scale (mRS) score, and mortality status in retrospectively reviewed. The effectiveness of the HALP score in predicting mortality within 90 days was assessed using the receiver operating characteristic ( ROC) curves. The optimal cutoff value for HALP was 13.10. ResultsA HALP score <13.10 increased the risk of death within 90 days and was associated with a higher incidence of large artery thrombosis. Cardioembolism and hyperlipidemia were more common in patients with high (>13) HALP scores. In addition to the HALP score, the length of hospital stay, 24-h National Institutes of Health Stroke Scale score (NIHSS), number of days of intubation, acute physiologic assessment and chronic health evaluation (APACHE) II score, and symptom-to-groin time were statistically significant risk factors for mortality within 90 days. DiscussionThe HALP score is an easily calculated, inexpensive, and noninvasive parameter that can be used to predict mortality in patients with MCA M1 occlusion undergoing reperfusion therapy. Low HALP scores indicate a poor prognosis. Thus, there is a relationship between the HALP score and survival.

Endovascular treatment for proximal middle cerebral artery occlusion due to underlying intracranial atherosclerotic disease: A retrospective single-center case series

ObjectiveTo compare treatment outcomes between patients who received a front-line stent-retriever thrombectomy (SRT) or first stenting without retrieval (FRESH) for treating proximal M1 occlusion due to underlying intracranial atherosclerotic disease (ICAD). MethodsWe retrospectively reviewed consecutive acute ischemic stroke (AIS) patients with intracranial large vessel occlusion (LVO) in the anterior circulation who underwent endovascular treatment (EVT) between January 2017 and August 2021 at Yeungnam University Medical Center. LVO in the anterior circulation was classified according to etiology as follows: Embolic group and ICAD group. Occlusion of the proximal M1 due to ICAD were enrolled in this study. The ICAD group was divided into SRT and FRESH groups according to the treatment method. ResultsAmong the 72 patients in the ICAD group, 55 patients had occlusion of the M1, and 27 had occlusion of the proximal M1 (27/55, 49.1 %). Among the 27 patients, 11 (40.7 %) underwent SRT and 16 (59.3 %) underwent FRESH. The puncture-to-recanalization time was significantly shorter in the FRESH group (28 min vs. 52 min, p = 0.023). Symptomatic ICH tended to occur more frequently in the SRT group than in the FRESH group (27.3 % vs. 0.0 %, p=0.056). There was a nonsignificant trend towards a good functional outcome in the FRESH group compared to the SRT group (81.3 % vs. 45.5 %, p=0.097). ConclusionIn the FRESH group, the puncture-to-recanalization time was significantly shorter, symptomatic ICH tended to occur less frequently, and good functional outcomes were more common.

Clinical comparison of aspiration to stentriever-mediated aspiration thrombectomy for M2 occlusions

ObjectiveWhile revascularization for M2 occlusions is generally recommended and considered beneficial, the optimal approach (aspiration vs stentriever/combined) is less well defined in the literature. We sought to compare outcomes after thrombectomy with manual aspiration thrombectomy alone (MAT) or stentriever-mediated aspiration thrombectomy (SMAT) Materials and MethodsTo circumvent inter-operator technical variability, patients underwent thrombectomy for M2 occlusions by a single operator and were stratified by first pass approach: manual aspiration thrombectomy (MAT/aspiration alone) and stentriever-mediated manual aspiration thrombectomy (SMAT/combination). Efficacy outcomes included good reperfusion (mTICI score ≥2b) and a favorable 90-day functional outcome (mRS score of ≤2). Safety outcomes included 90-day mortality and symptomatic intracranial hemorrhage. ResultsOne hundred three patients were identified: 57 underwent MAT whereas 46 underwent SMAT. Good reperfusion (TICI 2b or greater) was comparable between groups (93.5 % vs. 87.7 %, P=0.33). The intracranial hemorrhage rate was higher with SMAT compared to MAT (13 % vs. 1.8 %, P=0.04). Puncture-to-recanalization time was longer in SMAT (34.4 vs. 19.9 minutes, P<0.001). In multivariable analysis, complete or good reperfusion was associated with shorter puncture-recanalization time (adjusted odds ratio [aOR], 0.85) or less total passes (aOR, 0.58), respectively. In a propensity score matched analysis of 66 patients with comparable baseline and technical efficiency, the safety outcomes were not different between SMAT and MAT groups. ConclusionsSMAT compared with MAT did not result in an improved revascularization rate or functional outcome, while it was related to more hemorrhagic complications and mortality. Given cost and time savings with manual aspiration alone, this approach may be optimal as first line for M2 occlusions.

Effects of thrombus characteristics on clinical outcome and success of recanalization in acute ischemic stroke

Background: Despite current developments in mechanical thrombectomy (MT), successful recanalization cannot be achieved in all patients. One of the factors related to this is the characteristics of the thrombus. In this study, we aimed to evaluate the effects of thrombus length and permeability on procedural success and clinical outcome. Methods: Patients with intracranial ICA, middle cerebral artery M1, or M2 occlusions, who underwent MT between November 2019 and January 2022 were included in the study. Thrombus length, density and permeability were calculated and the relationship between recanalization success and modified Rankin Scores (mRS) at the 3rd month was evaluated. Good clinical outcome was defined as an mRS score of 2 or less. Results: Forty-six of the 79 patients included in the study had a good clinical outcome. Although thrombus length was shorter and permeability was higher in patients with good clinical outcome, statistical significance was not achieved. There was a positive correlation between thrombus density, thrombus length and the number of passes, and a negative correlation between permeability. There was no significant difference in thrombus length, density and permeability between patients with and without successful recanalisation. Thrombus length was found to be a predictor of clinical outcome at 3 months in univariate analysis, whereas only age was found to be an independent predictor in multivariate analysis. Conclusions: In conclusion, despite certain findings not achieving statistical significance, the observed trends offer valuable insights for future research. A comprehensive understanding of thrombus nature could guide personalized stroke treatment strategies in the future.

Combining the deployment of only the distal basket segment of the EMBOTRAP III and an aspiration catheter for M2 occlusions: the ONE-SEG technique.

Endovascular therapy (EVT) for distal medium vessel occlusions requires prioritizing effectiveness and safety. We developed a technique combining the deployment of only the distal basket segment of the EMBOTRAP III and an aspiration catheter (AC) for M2 occlusions, called the "ONE-SEG technique," and evaluated its clinical and technical impacts. This was a retrospective review of 30 consecutive patients with M2 segment middle cerebral artery occlusion treated using the ONE-SEG technique. This method involves deploying the EMBOTRAP III through a microcatheter in only one segment and guiding the AC to the M2 origin or distal M1. The rates of final-pass expanded thrombolysis in cerebral infarction (eTICI) scores of 2c/3 or 2b/2c/3, safety (symptomatic intracranial hemorrhage [sICH]), and clinical outcomes (modified Rankin Scale [mRS] score 0-2, 0-3 at 90 days, and mortality at 90 days) were evaluated. Of the 30 cases, 36.7% were female, and the mean age was 75.6 ± 11.0 years. The ONE-SEG technique was used for 17 cases (56.7%, median NIHSS 10 [5-15.5]) with primary M2 occlusion and 13 cases (43.3%, median NIHSS 20 [14-22.5]) with secondary M2 occlusion after proximal thrombus removal. The successful final reperfusion rate (eTICI 2b/2c/3) was 90% overall (27/30 cases). One case (3.3%) developed sICH with secondary M2 occlusion. At 3 months, mRS scores 0-2 were seen in 64.7% of patients with primary M2 occlusion (11/17 cases) and in 23.1% (3/13 cases) with secondary M2 occlusion. EVT using the ONE-SEG technique appears to be safe and effective for M2 occlusion.

Association Between the Timing of Atrial Fibrillation Detection and Functional Outcome Following Mechanical Thrombectomy.

Atrial fibrillation detected after stroke (AFDAS) refers to the identification of newly diagnosed atrial fibrillation (AF) following an ischemic stroke in patients without known AF (KAF). The objective of this study was to compare the functional outcomes of patients diagnosed with AFDAS and those with KAF who underwent mechanical thrombectomy. We conducted a retrospective analysis of patients who underwent mechanical thrombectomy and with either new AF diagnosed during hospitalization or KAF. We compared the baseline characteristics, clinical, and procedure-related variables between those with AFDAS and KAF. The primary outcome was the achievement of functional independence, defined as a modified Rankin Scale score of 0 to 2, at 3 months after stroke. Of the 252 patients, 101 (40.1%) were classified into the AFDAS group. The KAF group exhibited a higher rate of stroke history compared with the AFDAS group (32.5% versus 13.9%; P=0.001). Tandem occlusion was more common in the KAF group (13.2% versus 5.9%), while M2 occlusion was more common in the AFDAS group (11.3% versus 20.8%). The proportion of patients who achieved functional independence was higher in the AFDAS group (37.7% versus 52.5%; P=0.029). Multivariable analysis showed that AFDAS was associated with a favorable functional outcome (odds ratio, 2.67 [95% CI, 1.39-5.14]; P=0.003). AFDAS demonstrated a positive association with functional independence in patients with stroke who underwent mechanical thrombectomy and were finally diagnosed to have AF during hospitalization. The observed disparities in occlusion site, intractable thrombus, and history of previous stroke may have contributed to these findings.

Trevo 3 Mm and/or AXS Catalyst5 for the Treatment of Medium Distal Vessel Occlusion Stroke-results from the ASSIST Registry.

The effect of endovascular therapy (EVT) on the outcome of stroke patients with amedium distal vessel occlusion (MDVO) is unclear. We report the results of MDVO patients treated with the 3 mm Trevo stent retriever (SR) and/or the AXS Catalyst5 distal access catheter. Data was derived from aprospective, multicenter global registry (ASSIST registry) which enrolled patients treated with operator preferred EVT technique at 71sites from January 2019 to January 2022. Three techniques were assessed: SR classic, direct aspiration, and acombined approach. Additional inclusion criteria were (a)EVT performed with the 3 mm Trevo SR and/or AXS Catalyst5 distal access catheter on the first pass and (b)an occlusion of the M2segment or M3segment of the middle cerebral artery or the A1, A2 or A3segment of the anterior cerebral artery. The primary outcome was achieving an expanded Thrombolysis in Cerebral Infarction (eTICI) score of 2c or 3 on the first pass, with the primary technique as adjudicated by core lab. The primary clinical outcome measure was a90-day modified Rankin Scale (mRS) score of 0-2. Atotal of 155 patients (10.4% of the ASSIST population) were included. Most patients had an M2 occlusion (93.5%). First pass eTICI reperfusion was achieved in 43.1% of the patients. No modifying effect of the frontline technique was found. The rate of mRS 0-2 (overall 65.0%) did not significantly differ between groups. The data suggests that the Trevo 3 mm SR and/or the AXS Catalyst5 may be an option to treat medium distal vessel occlusion, but more data is needed to demonstrate safety and efficacy in this patient cohort. Further improvements are needed regarding materials and techniques to improve reperfusion results in this patient cohort in the future.

Management of patients with diffusion-weighted imaging-negative acute ischemic stroke: Retrospective analysis of 47 consecutive patients

BackgroundFew studies with a limited number of patients focused on the outcomes of patients with diffusion-weighted imaging (DWI)-negative acute ischemic stroke (AIS) after intravenous thrombolysis (IVT) and/or endovascular treatment (EVT). MethodsThis retrospective observational, single-center study included all consecutive patients admitted for AIS involving the anterior circulation and treated with IVT and/or EVT between January 1, 2015 and December 31, 2023. The collected data were used to identify the characteristics of patients with negative DWI and to compare outcomes in patients with negative and positive DWI. ResultsAmong the 1210 patients included, 47 (3.9 %) had negative (DWI-negative group) and 1163 had increased DWI signal (DWI-positive group). In the DWI-negative group, the mean age was 69 years (SD=19.4), 55.3 % were men, and 27 (57.4 %) had a large vessel occlusion. Thirty eight (80.9 %) were treated with IVT alone, 7 (14.9 %) with EVT alone, and 2 (4.3 %) with both. Fluid attenuated inversion recovery (FLAIR) sequences were the most sensitive to detect predictive factors of cerebral ischemia, such as vessel thrombosis and the spaghetti sign that were found in 68.1 % and 83 %, of patients, respectively. Oxyhemoglobin-sensitive (T2*) and susceptibility-weighted angiography (SWAN) sequences were less sensitive: vessel thrombosis and the brush sign were detected in 55.3 % and 19.1 % of patients, respectively. Comparison of the two DWI groups showed that M2 occlusion was more frequent (31.9 % vs 13 %, p<0.001) and M1 occlusion rarer (19.1 % vs 36 %, p<0.02) in the DWI-negative than DWI-positive group. At admission, the median National Institutes of Health Stroke Scale score was lower in the DWI-negative than DWI-positive group (2 vs 6, p=0.0001), but the median symptom onset-to-MRI time was similar in both groups (108 vs 111 min, p=0.88). ConclusionsIn patients with DWI-negative AIS, symptoms are less severe. Large vessel occlusions, notably in the M2 segment, are more distal at the expense of the M1 segment of MCA. The spaghetti sign remains the most predictive feature of AIS that should be specifically searched in the absence of DWI lesions.

Degree of subarachnoid hemorrhage affects clinical outcome after mechanical thrombectomy for M2 occlusion.

The prognostic relevance of post-mechanical thrombectomy (MT) subarachnoid hemorrhage (SAH) remains controversial. This study aimed to investigate whether the thickness of the SAH clot affects clinical outcomes following MT for M2 occlusion. A retrospective analysis was conducted on a prospective database of patients who underwent MT for isolated M2 occlusion. Patients were categorized into three groups based on the presence and thickness of SAH. Clinical and angiographical characteristics and outcomes were compared. Of the 36 patients included, SAH was observed in 15 (42%). When comparing patients with no SAH (grade 0) or thin SAH (grade 1) (N = 28) with those who had thick SAH (grade 2) (N = 8), patients with Grade 2 SAH required a higher number of passes and had a more severe angulation at M2. Patients with SAH Grade 2 had significantly worse NIHSS scores at 24 h (median, 4 vs. 14), but only one patient was identified as having a symptomatic intracranial hemorrhage. Patients with SAH Grade 2 were found to have a lower rate of favorable outcome (modified Rankin scale 0-2) (23% vs. 75%, P = 0.0026) and higher mortality (25% vs. 0%, P = 0.0499) at 90 days. The study found that thick SAH prevents clinical recovery after MT for M2 occlusion, even in cases of successful recanalization, and is associated with an unfavorable outcome. Thick SAH after MT is also linked to an increase in the number of passes and severe angulation at the M2 segment.

Interhospital Transfer for Endovascular Stroke Treatment in Canada: Results From the OPTIMISE Registry.

Interhospital transfer for patients with stroke due to large vessel occlusion for endovascular thrombectomy (EVT) has been associated with treatment delays. We analyzed data from Optimizing Patient Treatment in Major Ischemic Stroke With EVT, a quality improvement registry to support EVT implementation in Canada. We assessed for unadjusted differences in baseline characteristics, time metrics, and procedural outcomes between patients with large vessel occlusion transferred for EVT and those directly admitted to an EVT-capable center. Between January 1, 2018, and December 31, 2021, a total of 6803 patients received EVT at 20 participating centers (median age, 73 years; 50% women; and 50% treated with intravenous thrombolysis). Patients transferred for EVT (n=3376) had lower rates of M2 occlusion (22% versus 27%) and higher rates of basilar occlusion (9% versus 5%) compared with those patients presenting directly at an EVT-capable center (n=3373). Door-to-needle times were shorter in patients receiving intravenous thrombolysis before transfer compared with those presenting directly to an EVT center (32 versus 36 minutes). Patients transferred for EVT had shorter door-to-arterial access times (37 versus 87 minutes) but longer last seen normal-to-arterial access times (322 versus 181 minutes) compared with those presenting directly to an EVT-capable center. No differences in arterial access-to-reperfusion times, successful reperfusion rates (85% versus 86%), or adverse periprocedural events were found between the 2 groups. Patients transferred to EVT centers had a similar likelihood for good functional outcome (modified Rankin Scale score, 0-2; 41% versus 43%; risk ratio, 0.95 [95% CI, 0.88-1.01]; adjusted risk ratio, 0.98 [95% CI, 0.91-1.05]) and a higher risk for all-cause mortality at 90 days (29% versus 25%; risk ratio, 1.15 [95% CI, 1.05-1.27]; adjusted risk ratio, 1.14 [95% CI, 1.03-1.28]) compared with patients presenting directly to an EVT center. Patients transferred for EVT experience significant delays from the time they were last seen normal to the initiation of EVT.

Validation of a model for outcome prediction after endovascular treatment for ischemic stroke.

The recently developed MR-PREDICTS@24 h model showed excellent performance in the MR-CLEAN Registry cohort in patients presenting within 12 h from onset. However, its applicability to an U.S. population and to patients presenting beyond 12 h from last known normal are still undetermined. We aim to externally validate the MR-PREDICTS@24 h model in a new geographic setting and in the late window. In this retrospective analysis of a prospectively collected database from a comprehensive stroke center in the United States, we included patients with intracranial carotid artery or middle cerebral artery M1 or M2 segment occlusions who underwent endovascular therapy and applied the MR-PREDICTS@24 h formula to estimate the probabilities of functional outcome at day 90. The primary endpoint was the modified Rankin Scale (mRS) at 90 days. We included 1246 patients, 879 in the early (<12 h) and 367 in the late (≥12 h) cohort. For both cohorts, calibration and discrimination of the model were accurate throughout mRS levels, with absolute differences between estimated and predicted proportions ranging from 1% to 5%. Calibration metrics and curve inspections showed good performance for estimating the probabilities of mRS ≤ 1 to mRS ≤ 5 for the early cohort. For the late cohort, predictions were reliable for the probabilities of mRS ≤ 1 to mRS ≤ 4. The MR-PREDICTS@24 h was transferrable to a real-world U.S.-based cohort in the early window and showed consistently accurate predictions for patients presenting in the late window without need for updating.

Endovascular treatment of primary M3 occlusion stroke in clinical practice: analysis of the German Stroke Registry

BackgroundEndovascular treatment (ET) options for acute stroke due to distal middle cerebral artery occlusions are rapidly evolving, but data on outcome and safety are sparse. We therefore performed an analysis of patients undergoing ET for primary M3 occlusions in routine clinical practice in a nationwide registry.MethodsPatients enrolled between 01/20 and 12/21 in the prospective, multicenter German Stroke Registry-Endovascular Treatment (GSR-ET) were screened for mechanical thrombectomy performed for primary M3 occlusion. We analyzed neurological deficit as measured by the National Institute of Health Stroke Scale (NIHSS), symptomatic intracranial hemorrhage (sICH), thrombectomy technique, successful reperfusion (modified Thrombolysis in Cerebral Infarction [mTICI] score of 2b-3) and functional outcome as measured by the modified Rankin Scale (mRS) at discharge and 90 days.ResultsOut of 5574 patients, 11 patients (0.2%, median age 80 years, 54.5% female) underwent ET for primary M3 occlusion. All patients had pre-admission mRS ≤ 1, median NIHSS on admission was 8, and successful reperfusion was achieved in 6/11 patients (54.5%). While no vasospasm, dissection or perforation was reported, symptomatic intracranial hemorrhage occurred in 2 patients (18.2%). Favorable outcome (mRS ≤ 2) was achieved in 6/11 patients (54.5%) at 90-day follow-up.ConclusionsET for primary M3 occlusions is rarely performed. While technically feasible, the procedure’s potential benefits must be carefully weighed against its associated risks, including clinically relevant complications. Caution and further research is needed to optimize patient selection for this intervention.Trial RegistrationGSR-ET; ClinicalTrials.gov Identifier: NCT03356392; Trial Registration Date: 11/29/2017.

Assessment of automated TICI scoring during endovascular treatment in patients with an ischemic stroke

BackgroundThe extended Thrombolysis in Cerebral Infarction (eTICI) score is used in digital subtraction angiography (DSA) to quantify reperfusion grade in patients with an ischemic stroke who undergo endovascular thrombectomy (EVT)....

Comparative Analysis of Mechanical Thrombectomy Outcomes of Middle Cerebral Artery M1, M2 Superior, and M2 Inferior Occlusion Strokes

BackgroundThe M1 middle cerebral artery (MCA) commonly bifurcates into an M2 superior and an M2 inferior segment. However, MCA anatomy is highly variable rendering classification for mechanical thrombectomy (MT) trials difficult. Safety and effectiveness of M2 MCA stroke thrombectomy stratified by M2 MCA anatomy remains to be explored. MethodsLarge vessel occlusion strokes undergoing MT between 02/2016-08/2022 were reviewed (n=784). M1 (n=431) and M2 MCA (n=118) occlusions were assessed. Among M2 MCA occlusions only prototypical MCA bifurcation anatomy cases were included (n=99). Dominance was assessed based on angiography. Procedural and outcome data was compared between M1, M2 superior and M2 inferior MCA occlusions. ResultsBaseline demographics and periprocedural criteria of M2 superior (n=56) and M2 inferior (n=43) occlusion MTs were comparable. Among M2 inferior cases, the occluded branch was dominant in 41/43 (95.3%) but only in 37/56 (66.1%) among M2 superior cases (p<0.001). The 90-day favorable functional outcome (mRS 0-2) and mortality (mRS 6) rates were 60.0% and 8.9% in the M2 superior, 42.9% and 32.6% in the M2 inferior, and 44.1% and 26.0% in the M1 group (n=431). Compared to M2 superior, M2 inferior favorable outcome rates were lower (p=0.094) and mortality rates were higher (p=0.003) and resembled M1 outcome rates (p=0.750 and p=0.355, respectively). ConclusionIn setting of prototypical MCA bifurcation anatomy, thrombectomy of dominant M2 inferior occlusions had outcome rates like M1 occlusions. In contrast, M2 superior occlusions had significantly lower mortality rates and a trend towards better favorable functional outcome rates.

First-Line Aspiration Thrombectomy of M2 Occlusions with a Novel Reperfusion Catheter (REDTM 62): Real-World Experience from Two Tertiary Comprehensive Stroke Centers.

The direct aspiration first pass technique (ADAPT) is an effective and safe endovascular treatment for distal medium vessel occlusions (DMVOs). We evaluated technical features and initial results of a novel reperfusion catheter (REDTM 62) used for frontline aspiration thrombectomy of M2 occlusions in acute ischemic stroke patients. Appropriate aspiration catheters are crucial for a successful ADAPT maneuver; however, the selection of catheters suitable for smaller-sized vessels is scarce compared to the ones for large vessel occlusions. All patients treated with ADAPT using REDTM 62 as the frontline treatment approach for acute M2 occlusions between December 2022 and February 2024 were retrospectively enrolled. Demographic data, procedural timings and safety, recanalization rates, and outcome data were recorded. Twenty patients with a median admission National Institutes of Health Stroke Scale (NIHSS) score of 8 were identified. Successful revascularization (DMVO-thrombolysis in cerebral infarction [TICI]≥2b) with REDTM 62 aspiration thrombectomy was obtained in 65.0% (13/20) of cases. The first pass effect was 45.0% (9/20). In 2 cases, the REDTM 62 did not reach the clot due to marked distal vessel tortuosity. Stent retrievers were additionally used in 9 cases and led to an overall DMVO-TICI 2c/3 of 90.0% (18/20). Mean procedural time was 48 minutes. No complications directly related to ADAPT occurred. In-hospital mortality rate was 20.0% (4/20). The median discharge NIHSS score was 2.5. A good functional outcome at discharge (modified Rankin scale 0-2) was achieved in 55.0% (11/20) of cases. Our initial experiences with the novel REDTM 62 reperfusion catheter for treatment of M2 occlusions is in line with published data. ADAPT using this catheter may be considered as a safe and effective first-line treatment option. Further studies are warranted to validate the initial results.