Functional Outcomes Associated With Blood Pressure Decrease After Endovascular Thrombectomy.

Importance: The associations between blood pressure (BP) decreases induced by medication and functional outcomes in patients with successful endovascular thrombectomy remain uncertain. Objective: To evaluate whether BP reductions induced by intravenous BP medications are associated with poor functional outcomes at 3 months. Design, Setting, and Participants: This cohort study was a post hoc analysis of the Outcome in Patients Treated With Intra-Arterial Thrombectomy-Optimal Blood Pressure Control trial, a comparison of intensive and conventional BP management during the 24 hours after successful recanalization from June 18, 2020, to November 28, 2022. This study included 302 patients who underwent endovascular thrombectomy, achieved successful recanalization, and exhibited elevated BP within 2 hours of successful recanalization at 19 stroke centers in South Korea. Exposure: A BP decrease was defined as at least 1 event of systolic BP less than 100 mm Hg. Patients were divided into medication-induced BP decrease (MIBD), spontaneous BP decrease (SpBD), and no BP decrease (NoBD) groups. Main Outcomes and Measures: The primary outcome was a modified Rankin scale score of 0 to 2 at 3 months, indicating functional independence. Primary safety outcomes were symptomatic intracerebral hemorrhage within 36 hours and mortality due to index stroke within 3 months. Results: Of the 302 patients (median [IQR] age, 75 [66-82] years; 180 [59.6%] men), 47 (15.6%)were in the MIBD group, 39 (12.9%) were in the SpBD group, and 216 (71.5%) were in the NoBD group. After adjustment for confounders, the MIBD group exhibited a significantly smaller proportion of patients with functional independence at 3 months compared with the NoBD group (adjusted odds ratio [AOR], 0.45; 95% CI, 0.20-0.98). There was no significant difference in functional independence between the SpBD and NoBD groups (AOR, 1.41; 95% CI, 0.58-3.49). Compared with the NoBD group, the MIBD group demonstrated higher odds of mortality within 3 months (AOR, 5.15; 95% CI, 1.42-19.4). The incidence of symptomatic intracerebral hemorrhage was not significantly different among the groups (MIBD vs NoBD: AOR, 1.89; 95% CI, 0.54-5.88; SpBD vs NoBD: AOR, 2.75; 95% CI, 0.76-9.46). Conclusions and Relevance: In this cohort study of patients with successful endovascular thrombectomy after stroke, MIBD within 24 hours after successful recanalization was associated with poor outcomes at 3 months. These findings suggested lowering systolic BP to below 100 mm Hg using BP medication might be harmful.

Statin Therapy for Secondary Prevention in Ischemic Stroke Patients With Cerebral Microbleeds.

BACKGROUND AND OBJECTIVES: The association between statin use and the risk of intracranial hemorrhage (ICrH) following ischemic stroke (IS) or transient ischemic attack (TIA) in patients with cerebral microbleeds (CMBs) remains uncertain. This study investigated the risk of recurrent IS and ICrH in patients receiving statins based on the presence of CMBs. METHODS: We conducted a pooled analysis of individual patient data from the Microbleeds International Collaborative Network, comprising 32 hospital-based prospective studies fulfilling the following criteria: adult patients with IS or TIA, availability of appropriate baseline MRI for CMB quantification and distribution, registration of statin use after the index stroke, and collection of stroke event data during a follow-up period of ≥3 months. The primary endpoint was the occurrence of recurrent symptomatic stroke (IS or ICrH), while secondary endpoints included IS alone or ICrH alone. We calculated incidence rates and performed Cox regression analyses adjusting for age, sex, hypertension, atrial fibrillation, previous stroke, and use of antiplatelet or anticoagulant drugs to explore the association between statin use and stroke events during follow-up in patients with CMBs. RESULTS: In total, 16,373 patients were included (mean age 70.5 ± 12.8 years; 42.5% female). Among them, 10,812 received statins at discharge, and 4,668 had 1 or more CMBs. The median follow-up duration was 1.34 years (interquartile range: 0.32-2.44). In patients with CMBs, statin users were compared with nonusers. Compared with nonusers, statin therapy was associated with a reduced risk of any stroke (incidence rate [IR] 53 vs 79 per 1,000 patient-years, adjusted hazard ratio [aHR] 0.68 [95% CI 0.56-0.84]), a reduced risk of IS (IR 39 vs 65 per 1,000 patient-years, aHR 0.65 [95% CI 0.51-0.82]), and no association with the risk of ICrH (IR 11 vs 16 per 1,000 patient-years, aHR 0.73 [95% CI 0.46-1.15]). The results in aHR remained consistent when considering anatomical distribution and high burden (≥5) of CMBs. DISCUSSION: These observational data suggest that secondary stroke prevention with statins in patients with IS or TIA and CMBs is associated with a lower risk of any stroke or IS without an increased risk of ICrH. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that for patients with IS or TIA and CMBs, statins lower the risk of any stroke or IS without increasing the risk of ICrH.

Effectiveness of endovascular treatment for in-hospital stroke vs. community-onset stroke: a propensity score-matched analysis.

BACKGROUND: The effectiveness of endovascular treatment for in-hospital stroke remains debatable. We aimed to compare the outcomes between patients with in-hospital stroke and community-onset stroke who received endovascular treatment. METHODS: This prospective registry-based cohort study included consecutive patients who underwent endovascular treatment from January 2013 to December 2022 and were registered in the Selection Criteria in Endovascular Thrombectomy and Thrombolytic Therapy study and Yonsei Stroke Cohort. Functional outcomes at day 90, radiological outcomes, and safety outcomes were compared between the in-hospital and community-onset groups using logistic regression and propensity score-matched analysis. RESULTS: Of 1,219 patients who underwent endovascular treatment, 117 (9.6%) had in-hospital stroke. Patients with in-hospital onset were more likely to have a pre-stroke disability and active cancer than those with community-onset. The interval from the last known well to puncture was shorter in the in-hospital group than in the community-onset group (155 vs. 355 min, p<0.001). No significant differences in successful recanalization or safety outcomes were observed between the groups; however, the in-hospital group exhibited worse functional outcomes and higher mortality at day 90 than the community-onset group (all p<0.05). After propensity score matching including baseline characteristics, functional outcomes after endovascular treatment did not differ between the groups (OR: 1.19, 95% CI 0.78-1.83, p=0.4). Safety outcomes did not significantly differ between the groups. CONCLUSION: Endovascular treatment is a safe and effective treatment for eligible patients with in-hospital stroke. Our results will help physicians in making decisions when planning treatment and counseling caregivers or patients.

Initial stroke severity and discharge outcome in patients with muscle mass deficit.

This study aimed to investigate the association between muscle mass deficit and the initial severity of ischemic stroke. The impact of muscle mass deficit on the discharge outcome was also evaluated. This retrospective study included 660 patients with acute ischemic stroke who underwent bioelectrical impedance analyses. We compared the National Institute of Health Stroke Scale (NIHSS) score, occurrence of moderate stroke (NIHSSS ≥ 5) at admission, and unfavorable functional outcome (modified Rankin Scale score ≥ 2) at discharge between patients with and without muscle mass deficit using Poisson and logistic regression analyses. The mean age of the study patients was 65.6 ± 13.0, and 63.3% were males. Muscle mass deficit was present in 24.4% of patients. Muscle mass deficit was significantly and independently associated with NIHSS score or moderate stroke (all p < 0.05). This association was noted regardless of patient characteristics. Among the respective NIHSS items, muscle mass deficit was significantly associated with facial palsy, motor function of the arm or leg, limb ataxia, and dysarthria. Muscle mass deficit also led to unfavorable functional outcome, which was mediated by the initial NIHSS score. In conclusion, muscle mass deficit is associated with higher NIHSS score and unfavorable functional outcome in patients with acute ischemic stroke.

Clinical Associations and Prognostic Value of MRI-Visible Perivascular Spaces in Patients With Ischemic Stroke or TIA: A Pooled Analysis

BACKGROUND AND OBJECTIVES: Visible perivascular spaces are an MRI marker of cerebral small vessel disease and might predict future stroke. However, results from existing studies vary. We aimed to clarify this through a large collaborative multicenter analysis. METHODS: We pooled individual patient data from a consortium of prospective cohort studies. Participants had recent ischemic stroke or transient ischemic attack (TIA), underwent baseline MRI, and were followed up for ischemic stroke and symptomatic intracranial hemorrhage (ICH). Perivascular spaces in the basal ganglia (BGPVS) and perivascular spaces in the centrum semiovale (CSOPVS) were rated locally using a validated visual scale. We investigated clinical and radiologic associations cross-sectionally using multinomial logistic regression and prospective associations with ischemic stroke and ICH using Cox regression. RESULTS: We included 7,778 participants (mean age 70.6 years; 42.7% female) from 16 studies, followed up for a median of 1.44 years. Eighty ICH and 424 ischemic strokes occurred. BGPVS were associated with increasing age, hypertension, previous ischemic stroke, previous ICH, lacunes, cerebral microbleeds, and white matter hyperintensities. CSOPVS showed consistently weaker associations. Prospectively, after adjusting for potential confounders including cerebral microbleeds, increasing BGPVS burden was independently associated with future ischemic stroke (versus 0-10 BGPVS, 11-20 BGPVS: HR 1.19, 95% CI 0.93-1.53; 21+ BGPVS: HR 1.50, 95% CI 1.10-2.06; p = 0.040). Higher BGPVS burden was associated with increased ICH risk in univariable analysis, but not in adjusted analyses. CSOPVS were not significantly associated with either outcome. DISCUSSION: In patients with ischemic stroke or TIA, increasing BGPVS burden is associated with more severe cerebral small vessel disease and higher ischemic stroke risk. Neither BGPVS nor CSOPVS were independently associated with future ICH.

Association between substantia nigra degeneration and functional outcome in patients with basal ganglia infarction.

BACKGROUND AND PURPOSE: Cerebral infarction in the basal ganglia may cause secondary and delayed neuronal degeneration in the substantia nigra (SN). However, the clinical significance of SN degeneration remains poorly understood. METHODS: This retrospective observational study included patients with acute ischemic stroke in the basal ganglia on initial diffusion-weighted imaging who underwent follow-up diffusion-weighted imaging between 4 and 30 days after symptom onset. SN degeneration was defined as a hyperintensity lesion in the SN observed on diffusion-weighted imaging. We compared functional outcomes at 3 months between patients with and without SN degeneration. A poor outcome was defined as a score of 3-6 (functional dependence or death) on the modified Rankin Scale. RESULTS: Of 350 patients with basal ganglia infarction (median age = 74.0 years, 53.7% male), 125 (35.7%) had SN degeneration. The proportion of functional dependence or death was 79.2% (99/125 patients) in patients with SN degeneration, which was significantly higher than that in those without SN degeneration (56.4%, 127/225 patients, p < 0.001). SN degeneration was more frequent in patients with functional dependence or death (99/226 patients, 43.8%) than in those with functional independence (26/124 patients, 21.0%, p < 0.001). Multivariable logistic regression analysis showed a significant association between SN degeneration and functional dependence or death (odds ratio = 2.91, 95% confidence interval = 1.17-7.21, p = 0.021). CONCLUSIONS: The study showed that patients with degeneration of SN were associated with functional dependence or death at 3 months, suggesting that secondary degeneration is a predictor of poor stroke outcomes and a potential therapeutic target.

Preprocedural D-Dimer Level as a Predictor of First-Pass Recanalization and Functional Outcome in Endovascular Treatment of Acute Ischemic Stroke.

We aimed to evaluate the association between preprocedural D-dimer levels and endovascular and clinical outcomes. We retrospectively reviewed patients with acute intracranial large-vessel occlusion who underwent mechanical thrombectomy. Plasma D-dimer levels were measured immediately before the endovascular procedure. Endovascular outcomes included successful recanalization, first-pass recanalization (first-pass effect (FPE) and modified FPE (mFPE)), thrombus fragmentation, and the number of passes of the thrombectomy device. Clinical outcomes were assessed at 3 months using the modified Rankin Scale. A total of 215 patients were included. Preprocedural D-dimer levels were lower in patients with FPE (606.0 ng/mL [interquartile range, 268.0-1062.0]) than in those without (879.0 ng/mL [437.0-2748.0]; p = 0.002). Preprocedural D-dimer level was the only factor affecting FPE (odds ratio, 0.92 [95% confidence interval, 0.85-0.98] per 500 ng/mL; p = 0.022). D-dimer levels did not differ significantly based on successful recanalization and thrombus fragmentation. The number of passes of the thrombectomy device was higher (p = 0.002 for trend) and the puncture-to-recanalization time was longer (p = 0.044 for trend) as the D-dimer levels increased. Patients with favorable outcome had significantly lower D-dimer levels (495.0 ng/mL [290.0-856.0]) than those without (1189.0 ng/mL [526.0-3208.0]; p < 0.001). Preprocedural D-dimer level was an independent factor for favorable outcome (adjusted odds ratio, 0.88 [0.81-0.97] per 500 ng/mL; p = 0.008). In conclusion, higher preprocedural D-dimer levels were significantly associated with poor endovascular and unfavorable functional outcomes.

Coagulation Factor Expression and Composition of Arterial Thrombi in Cancer-Associated Stroke.

BACKGROUND: Cancer is associated with an increased risk of stroke. Tumor cells activate platelets, induce a coagulation cascade, and generate thrombin. The composition of thrombi may reflect the mechanism of thrombosis, aiding the determination of the treatment strategy. Here, we investigated the composition and expression of coagulation factors in the thrombi of patients with cancer-associated stroke. METHODS: Patients with stroke who underwent endovascular thrombectomy between September 2014 and June 2020 and whose cerebral thrombi were obtained were divided into those with cancer-associated stroke (cancer group) and propensity score-matched patients without cancer (control group), using 1:1 matching based on age and sex. Immunohistochemistry was performed of the thrombi, and the composition and expression of coagulation factors were compared between groups. RESULTS: Among the 320 patients who underwent endovascular thrombectomy and who had thrombi obtained, this study included 23 patients with cancer and 23 matched controls. In both groups, the median age was 65 years, and 12 patients (52.2%) were men. Platelet composition was significantly higher in the cancer group than in the control group (median [interquartile range], 51.3% [28.0%-61.4%] versus 9.5% [4.8%-14.0%]; P<0.001). Among coagulation factors, thrombin (26.2% [16.2%-52.7%] versus 4.5% [1.3%-7.2%]; P<0.001) and tissue factors (0.60% [0.34%-2.06%] versus 0.37% [0.22%-0.60%]; P=0.024) were higher and factor X was lower (1.25% [0.39%-3.60%] versus 2.33% [1.67%-4.48%]; P=0.034) in the cancer group. There was a positive correlation between thrombin and platelets in the cancer group (r=0.666; P=0.001) but not in the control group (r=-0.167; P=0.627). CONCLUSIONS: Cerebral thrombi in patients with cancer-associated stroke showed higher proportions of platelets, thrombin, and tissue factors, suggesting their key roles in arterial thrombosis in cancer and providing a therapeutic perspective for preventing stroke in patients with cancer-associated stroke.

Clinical Benefit of First-Pass Recanalization Is Time-Dependent in Endovascular Treatment of Acute Ischemic Stroke.

Clinical benefit can be time-dependent even after first-pass recanalization (FPR) in endovascular treatment of acute stroke. This study aimed to evaluate the association between favorable outcome and FPR under a specific time frame. Patients who underwent mechanical thrombectomy were retrospectively reviewed. Recanalization status was categorized into four groups based on FPR and dichotomized time from groin puncture to recanalization (P-to-R time). Favorable outcomes were compared between groups. A total of 458 patients were included. As the cutoff of P-to-R time for favorable outcome was 30 min, recanalization status was categorized into FPR (+) with a P-to-R time ≤ 30 min (Group 1), FPR (-) with a P-to-R time ≤ 30 min (Group 2), FPR (+) with a P-to-R time > 30 min (Group 3), and FPR (-) with a P-to-R time > 30 min (Group 4). Favorable outcomes in Group 3 (37.5%) were significantly less frequent than those in Group 1 (60.4%, p = 0.029) and Group 2 (59.5%, p = 0.033) but were not significantly different from those in Group 4 (35.7%, p = 0.903). Compared to Group 1, Group 3 (adjusted odds ratio, 0.30 [95% confidence interval, 0.12-0.76]; p = 0.011) and Group 4 (0.25 [0.14-0.48]; p < 0.001) were adversely associated with favorable outcomes. FPR was associated with functional outcome in a time-dependent manner. Even for patients who have achieved FPR, their functional outcome might not be favorable if the P-to-R time is >30 min.

Intensive vs Conventional Blood Pressure Lowering After Endovascular Thrombectomy in Acute Ischemic Stroke: The OPTIMAL-BP Randomized Clinical Trial.

Importance: Optimal blood pressure (BP) control after successful reperfusion with endovascular thrombectomy (EVT) for patients with acute ischemic stroke is unclear. Objective: To determine whether intensive BP management during the first 24 hours after successful reperfusion leads to better clinical outcomes than conventional BP management in patients who underwent EVT. Design, Setting, and Participants: Multicenter, randomized, open-label trial with a blinded end-point evaluation, conducted across 19 stroke centers in South Korea from June 2020 to November 2022 (final follow-up, March 8, 2023). It included 306 patients with large vessel occlusion acute ischemic stroke treated with EVT and with a modified Thrombolysis in Cerebral Infarction score of 2b or greater (partial or complete reperfusion). Interventions: Participants were randomly assigned to receive intensive BP management (systolic BP target <140 mm Hg; n = 155) or conventional management (systolic BP target 140-180 mm Hg; n = 150) for 24 hours after enrollment. Main Outcomes and Measures: The primary outcome was functional independence at 3 months (modified Rankin Scale score of 0-2). The primary safety outcomes were symptomatic intracerebral hemorrhage within 36 hours and death related to the index stroke within 3 months. Results: The trial was terminated early based on the recommendation of the data and safety monitoring board, which noted safety concerns. Among 306 randomized patients, 305 were confirmed eligible and 302 (99.0%) completed the trial (mean age, 73.0 years; 122 women [40.4%]). The intensive management group had a lower proportion achieving functional independence (39.4%) than the conventional management group (54.4%), with a significant risk difference (-15.1% [95% CI, -26.2% to -3.9%]) and adjusted odds ratio (0.56 [95% CI, 0.33-0.96]; P = .03). Rates of symptomatic intracerebral hemorrhage were 9.0% in the intensive group and 8.1% in the conventional group (risk difference, 1.0% [95% CI, -5.3% to 7.3%]; adjusted odds ratio, 1.10 [95% CI, 0.48-2.53]; P = .82). Death related to the index stroke within 3 months occurred in 7.7% of the intensive group and 5.4% of the conventional group (risk difference, 2.3% [95% CI, -3.3% to 7.9%]; adjusted odds ratio, 1.73 [95% CI, 0.61-4.92]; P = .31). Conclusions and Relevance: Among patients who achieved successful reperfusion with EVT for acute ischemic stroke with large vessel occlusion, intensive BP management for 24 hours led to a lower likelihood of functional independence at 3 months compared with conventional BP management. These results suggest that intensive BP management should be avoided after successful EVT in acute ischemic stroke. Trial Registration: ClinicalTrials.gov Identifier: NCT04205305.

Association of clot ultrastructure with clot perviousness in stroke patients.

Clot perviousness on computerized tomography (CT) is predictive of response to reperfusion therapy. This study aimed to determine the association of clot perviousness with ultrastructural features of clot in stroke patients undergoing endovascular thrombectomy. We quantitatively analyzed the ultrastructural components identified using scanning electron microscopy. The clot components were determined in the inner portions of the clots. Clot perviousness was assessed as thrombus attenuation increase (TAI) using noncontrast CT and CT angiography. We compared the association between the identified ultrastructural components and clot perviousness. The proportion of pores consisted of 3.5% on scanning electron microscopy images. The proportion of porosity in the inner portion was 2.5%. Among the ultrastructural components, polyhedrocytes were most commonly observed. The mean TAI was 9.3 ± 10.0 (median 5.6, interquartile range 1.1-14.3) Hounsfield units. TAI correlated positively with inner porosity (r = 0.422, p = 0.020). Among the ultrastructural clot components, TAI was independently associated with polyhedrocytes (B = - 0.134, SE = 0.051, p = 0.008). Clot perviousness is associated with porosity and the proportion of polyhdrocytes of clots.

Corrigendum: Clinical implications of atrial fibrillatioN detection using wearabLE devices in patients with cryptogenic stroke (CANDLE-AF) trial: Design and rationale.

[This corrects the article DOI: 10.3389/fcvm.2022.837958.].

Differential association between apolipoprotein B and LDL cholesterol and cerebral atherosclerosis according to pre-stroke statin use.

BACKGROUND AND AIMS: To reduce cardiovascular risk, low-density lipoprotein cholesterol (LDL-C) is the primary target of statin treatment, while apolipoprotein B (ApoB) is secondary. We investigated the association between atherosclerotic stenosis and LDL-C or ApoB levels and whether a difference in association exists according to pre-admission statin use in ischemic stroke patients. METHODS: This retrospective cross-sectional study included consecutive patients with acute ischemic stroke or transient ischemic attack who underwent lipid profile and angiographic testing. Patients were categorized into four groups according to stenosis location: normal, extracranial atherosclerotic stenosis (ECAS), intracranial atherosclerotic stenosis (ICAS), or ECAS + ICAS. Subgroup analyses were performed by pre-admission statin use. RESULTS: Of the 6338 patients included, 1980 (31.2%) were in the normal group, 718 (11.3%) in the ECAS group, 1845 (29.1%) in the ICAS group, and 1795 (28.3%) in the ECAS + ICAS group. Both LDL-C and ApoB levels were associated with every location of stenosis. A significant interaction was found between pre-admission statin use and LDL-C level (p for interaction <0.05). LDL-C was associated with stenosis only in statin-naïve patients, whereas ApoB was associated with ICAS, with or without ECAS, in both statin-naïve and statin-treated patients. ApoB also showed a consistent association with symptomatic ICAS in both statin-treated and statin-naïve patients, whereas LDL-C did not. CONCLUSIONS: ApoB was consistently associated with ICAS, particularly symptomatic stenosis, in both statin-naïve and statin-treated patients. The close association between ApoB levels and residual risk in statin-treated patients could be partially explained by these results.

First-Pass Recanalization with EmboTrap II in Acute Ischemic Stroke (FREE-AIS): A Multicenter Prospective Study.

OBJECTIVE: We aimed to evaluate the efficacy of EmboTrap II in terms of first-pass recanalization and to determine whether it could yield favorable outcomes. MATERIALS AND METHODS: In this multicenter, prospective study, we consecutively enrolled patients who underwent mechanical thrombectomy using EmboTrap II as a front-line device. The primary outcome was the first pass effect (FPE) rate defined by modified Thrombolysis In Cerebral Infarction (mTICI) grade 2c or 3 by the first pass of EmboTrap II. In addition, modified FPE (mFPE; mTICI grade 2b-3 by the first pass of EmboTrap II), successful recanalization (final mTICI grade 2b-3), and clinical outcomes were assessed. We also analyzed the effect of FPE on a modified Rankin Scale (mRS) score of 0-2 at 3 months. RESULTS: Two hundred-ten patients (mean age ± standard deviation, 73.3 ± 11.4 years; male, 55.7%) were included. Ninety-nine patients (47.1%) had FPE, and mFPE was achieved in 150 (71.4%) patients. Successful recanalization was achieved in 191 (91.0%) patients. Among them, 164 (85.9%) patients underwent successful recanalization by exclusively using EmboTrap II. The time from groin puncture to FPE was 25.0 minutes (interquartile range, 17.0-35.0 minutes). Procedure-related complications were observed in seven (3.3%) patients. Symptomatic intracranial hemorrhage developed in 14 (6.7%) patients. One hundred twenty-three (58.9% of 209 completely followed) patients had an mRS score of 0-2. Sixteen (7.7% of 209) patients died during the follow-up period. Patients who had successful recanalization with FPE were four times more likely to have an mRS score of 0-2 than those who had successful recanalization without FPE (adjusted odds ratio, 4.13; 95% confidence interval, 1.59-10.8; p = 0.004). CONCLUSION: Mechanical thrombectomy using the front-line EmboTrap II is effective and safe. In particular, FPE rates were high. Achieving FPE was important for an mRS score of 0-2, even in patients with successful recanalization.

Stroke Risk and Antithrombotic Treatment During Follow-up of Patients With Ischemic Stroke and Cortical Superficial Siderosis.

BACKGROUND AND OBJECTIVES: In patients with ischemic stroke (IS) or transient ischemic attack (TIA) and cortical superficial siderosis (cSS), there are few data regarding the risk of future cerebrovascular events and also about the benefits and safety of antithrombotic drugs for secondary prevention. We investigated the associations of cSS and stroke risk in patients with recent IS or TIA. METHODS: We retrospectively analyzed the Microbleeds International Collaborative Network (MICON) database. We selected patients with IS or TIA from cohorts who had MRI-assessed cSS, available data on antithrombotic treatments, recurrent cerebrovascular events (intracranial hemorrhage [ICrH], IS, or any stroke [ICrH or IS]), and mortality. We calculated incidence rates (IRs) and performed univariable and multivariable Cox regression analyses. RESULTS: Of 12,669 patients (mean age 70.4 ± 12.3 years, 57.3% men), cSS was detected in 273 (2.2%) patients. During a mean follow-up of 24 ± 17 months, IS was more frequent than ICrH in both cSS (IR 57.1 vs 14.6 per 1,000 patient-years) and non-cSS (33.7 vs 6.3 per 1,000 patient-years) groups. Compared with the non-cSS group, cSS was associated with any stroke on multivariable analysis {IR 83 vs 42 per 1,000 patient-years, adjusted hazard ratio [HR] for cSS 1.62 (95% CI: 1.14-2.28; p = 0.006)}. This association was not significant in subgroups of patients treated with antiplatelet drugs (n = 6,554) or with anticoagulants (n = 4,044). Patients with cSS who were treated with both antiplatelet drugs and anticoagulants (n = 1,569) had a higher incidence of ICrH (IR 107.5 vs 4.9 per 1,000 patient-years, adjusted HR 13.26; 95% CI: 2.90-60.63; p = 0.001) and of any stroke (IR 198.8 vs 34.7 per 1,000 patient-years, adjusted HR 5.03; 95% CI: 2.03-12.44; p < 0.001) compared with the non-cSS group. DISCUSSION: Patients with IS or TIA with cSS are at increased risk of stroke (ICrH or IS) during follow-up; the risk of IS exceeds that of ICrH for patients receiving antiplatelet or anticoagulant treatment alone, but the risk of ICrH exceeds that of IS in patients receiving both treatments. The findings suggest that either antiplatelet or anticoagulant treatment alone should not be avoided in patients with cSS, but combined antithrombotic therapy might be hazardous. Our findings need to be confirmed by randomized clinical trials.

Preprocedural determination of an occlusion pathomechanism in endovascular treatment of acute stroke: a machine learning-based decision.

OBJECTIVE: To evaluate whether an occlusion pathomechanism can be accurately determined by common preprocedural findings through a machine learning-based prediction model (ML-PM). METHODS: A total of 476 patients with acute stroke who underwent endovascular treatment were retrospectively included to derive an ML-PM. For external validation, 152 patients from another tertiary stroke center were additionally included. An ML algorithm was trained to classify an occlusion pathomechanism into embolic or intracranial atherosclerosis. Various common preprocedural findings were entered into the model. Model performance was evaluated based on accuracy and area under the receiver operating characteristic curve (AUC). For practical utility, a decision flowchart was devised from an ML-PM with a few key preprocedural findings. Accuracy of the decision flowchart was validated internally and externally. RESULTS: An ML-PM could determine an occlusion pathomechanism with an accuracy of 96.9% (AUC=0.95). In the model, CT angiography-determined occlusion type, atrial fibrillation, hyperdense artery sign, and occlusion location were top-ranked contributors. With these four findings only, an ML-PM had an accuracy of 93.8% (AUC=0.92). With a decision flowchart, an occlusion pathomechanism could be determined with an accuracy of 91.2% for the study cohort and 94.7% for the external validation cohort. The decision flowchart was more accurate than single preprocedural findings for determining an occlusion pathomechanism. CONCLUSIONS: An ML-PM could accurately determine an occlusion pathomechanism with common preprocedural findings. A decision flowchart consisting of the four most influential findings was clinically applicable and superior to single common preprocedural findings for determining an occlusion pathomechanism.

Neutrophil Recruitment in Arterial Thrombus and Characteristics of Stroke Patients with Neutrophil-Rich Thrombus.

PURPOSE: Neutrophils contribute to thrombosis. However, there is limited information on the temporal course of neutrophil recruitment in thrombosis, the contribution of neutrophils to thrombus growth, and the characteristics of stroke patients with neutrophil-rich thrombi. MATERIALS AND METHODS: After inducing carotid artery thrombosis in Institute of Cancer Research mice using ferric chloride, aged thrombi were produced by ligating the distal portion of the carotid artery in mice for 0.5, 1, 2, 3, 6, or 24 h. For thrombus analysis in stroke patients, we used registry data and thrombi that were obtained during intra-arterial thrombectomy. Immunohistochemistry was performed to determine thrombus composition. RESULTS: In the thrombi of 70 mice, Ly6G positive cell counts (neutrophils) and histone H3-positive cell counts increased in a time-dependent manner (both p<0.001). Ly6G-positive cell count was strongly correlated with histone H3-positive cell counts (r=0.910, p<0.001), but not with thrombus size (p=0.320). In 75 stroke patients, atrial fibrillation and cardioembolism were more frequent in the higher neutrophil group (32/37, 86.5%) than in the lower neutrophil group (19/38, 50%) (p=0.002). The median erythrocyte fraction was higher [52.0 (interquartile range 39.9-57.8)] in the higher neutrophil group than in the lower neutrophil group [40.3 (interquartile range 23.5-53.2)]. The fraction of neutrophils was positively correlated with that of erythrocytes (R=0.35, p=0.002). CONCLUSION: Neutrophils were recruited and increased in arterial thrombosis in a time-dependent manner; however, they were not associated with the growth of formed thrombi. Neutrophil fractions in the thrombi of stroke patients appeared to be associated with atrial fibrillation and erythrocyte fraction.

Impact of Renal Function on Short-Term Outcome After Reperfusion Therapy in Patients With Ischemic Stroke.

BACKGROUND: A high and low estimated glomerular filtration rate (eGFR) could affect outcomes after reperfusion therapy for ischemic stroke. This study aimed to determine whether renal function based on eGFR affects mortality risk in patients with ischemic stroke within 6 months following reperfusion therapy. METHODS: This prospective registry-based cohort study included 2266 patients who received reperfusion therapy between January 2000 and September 2019 and were registered in the SECRET (Selection Criteria in Endovascular Thrombectomy and Thrombolytic Therapy) study or the Yonsei Stroke Cohort. A high and low eGFR were based on the Chronic Kidney Disease Epidemiology Collaboration equation and defined, respectively, as the 5th and 95th percentiles of age- and sex-specific eGFR. Occurrence of death within 6 months was compared among the groups according to their eGFR such as low, normal, or high eGFR. RESULTS: Of the 2266 patients, 2051 (90.5%) had a normal eGFR, 110 (4.9%) a low eGFR, and 105 (4.6%) a high eGFR. Patients with high eGFR were younger or less likely to have hypertension, diabetes, or atrial fibrillation than the other groups. Active cancer was more prevalent in the high-eGFR group. During the 6-month follow-up, there were 24 deaths (22.9%) in the high-eGFR group, 37 (33.6%) in the low-eGFR group, and 237 (11.6%) in the normal-eGFR group. After adjusting for variables with P<0.10 in the univariable analysis, 6-month mortality was independently associated with high eGFR (hazard ratio, 2.22 [95% CI, 1.36-3.62]; P=0.001) and low eGFR (HR, 2.29 [95% CI, 1.41-3.72]; P=0.001). These associations persisted regardless of treatment modality or various baseline characteristics. CONCLUSIONS: High eGFR as well as low eGFR were independently associated with 6-month mortality after reperfusion therapy. Kidney function could be considered a prognostic factor in patients with ischemic stroke after reperfusion therapy.