Low-Dose versus Standard-Dose Intravenous Alteplase in Acute Ischemic Stroke

Patterns and Clinical Implications of Hemorrhagic Transformation After Thrombolysis in Acute Ischemic Stroke: Results From the ENCHANTED Study

BACKGROUND AND OBJECTIVES

Hemorrhagic transformation may be a potentially devastating complication of IV thrombolysis (IVT) in acute ischemic stroke, but what degree of hemorrhage indicates the greatest negative effect is not known. We aimed to define the associations between hemorrhagic transformation patterns, classified according to clinical and imaging categories, and clinical outcomes after IVT.

METHODS

We conducted a post hoc analysis from the international Enhanced Control of Hypertension and Thrombolysis Stroke Study. Symptomatic intracerebral hemorrhage (sICH) was defined based on established criteria, such as the Safe Implementation of Thrombolysis in Stroke-Monitoring Study (SITS-MOST) criteria. Asymptomatic intracerebral hemorrhage (aICH) was defined as any intracerebral hemorrhage that did not meet the criteria for sICH. Imaging subtypes of hemorrhagic transformation were assessed using the Heidelberg Bleeding Classification system. The primary outcome was death or major disability, defined by modified Rankin scale (mRS) scores 3-6 at 90 days. Secondary outcomes included death, death or disability (mRS 2-6), and poor health-related quality of life (HRQoL), defined as an overall heath utility score ≤0.7 (mean).

RESULTS

Of the 4,370 participants, 779 (17.8%) developed any intracranial hemorrhage (ICH), with a median time from randomization to hemorrhage of 23.5 hours (interquartile range 18.92-26.07). According to the SITS-MOST criteria, 62 patients (1.4% of 4,370) were classified as sICH, and 717 patients (16.4% of 4,370) were classified as aICH. sICH per SITS-MOST criteria was associated with death or major disability (odds ratio [OR] 23.05, 95% CI 8.97-59.23), death (OR 20.14, 95% CI 11.32-35.84), death or disability (OR 61.36, 95% CI 8.40-448.01), and poor HRQoL (OR 17.87, 95% CI 7.47-42.71). Similarly, aICH per SITS-MOST criteria was also associated with death or major disability (OR 2.23, 95% CI 1.84-2.70), death (OR 1.82, 95% CI 1.39-2.38), death or disability (OR 2.29, 95% CI 1.87-2.80), and poor HRQoL (OR 1.81, 95% CI 1.50-2.18). Comparable associations were observed for sICH and aICH defined by other criteria, as well as for imaging subtypes based on Heidelberg Bleeding Classification system.

DISCUSSION

All forms of post-IVT hemorrhagic transformation in acute ischemic stroke are associated with increased odds of poor clinical outcomes. Of note, aICH after IVT should not be considered clinically innocuous.

TRIAL REGISTRATION INFORMATION

ClinicalTrials.gov (NCT01422616).

Successful recovery of vision following intravenous thrombolysis using low-dose alteplase in central retinal artery occlusion

Central retinal artery occlusion (CRAO) is an ophthalmic emergency characterized by sudden loss of vision with a low chance of spontaneous recovery. This case report presents a 49-year-old female with sudden right eye visual loss, diagnosed as non-arteritic CRAO. Fundoscopic examination revealed retinal pallor, and optical coherence tomography demonstrated edema of the inner retinal layer, consistent with CRAO. Brain magnetic resonance imaging (MRI) showed an acute ischemic lesion in the right occipital subcortex. The patient received intravenous recombinant tissue plasminogen activator (IV rt-PA) at a lower-than-standard dose of 0.6 mg/kg within 4 h and 17 min of symptom onset, resulting in significant visual improvement. Extensive etiological investigation, including transesophageal echocardiography, uncovered a large, high-risk patent foramen ovale (PFO), leading to the diagnosis of PFO-associated CRAO and concomitant embolic stroke. This case suggests the effectiveness of low-dose IV rt-PA in treating CRAO, which might offer comparable efficacy to the standard dose while potentially minimizing bleeding risks. It also emphasizes the importance of considering cardiac comorbidities, particularly PFO, in younger CRAO patients, and underscores the need for a multidisciplinary approach and comprehensive stroke-etiology workups in CRAO management. This report contributes to the limited evidence on CRAO treatment in Japan, particularly in the context of lower tPA dosing and associated cardiac abnormalities. It underscores the importance of early diagnosis, treatment, and thorough etiological investigation in improving outcomes for CRAO patients.

Intravenous alteplase before endovascular therapy for acute large vessel occlusion with large ischemic core: subanalysis of a randomized clinical trial

BACKGROUND

The efficacy of endovascular therapy (EVT) in patients with large ischemic core has been reported, but it remains unclear whether IV alteplase (IVT) has beneficial effects in addition to EVT in such patients. We evaluated the efficacy and safety of EVT with or without IVT.

METHODS

The RESCUE-Japan LIMIT was an open-label, prospective, multicenter, randomized clinical trial to evaluate the efficacy and safety of EVT in stroke patients with large ischemic core, defined as Alberta Stroke Program Early CT Score (ASPECTS) 3-5. This subanalysis evaluated the differences in the effects of EVT with medical care (EVT group) compared with medical care alone (No-EVT group) between those who received IVT (IVT stratum) and those who did not (No-IVT stratum) before EVT.

RESULTS

Among 202 enrolled patients, 147 (73%) did not receive IVT. In the No-IVT stratum, the modified Rankin Scale (mRS) score of 0-3 at 90 days was significantly higher in the EVT group than in the No-EVT group (31.1% vs 12.3%, OR 3.21 (95% CI 1.37 to 7.53)). In the IVT stratum, the mRS score of 0-3 was 30.8% in the EVT group and 13.8% in the No-EVT group (OR 2.78 (95% CI 0.72 to 10.7)) (interaction p=0.77). The incidence of symptomatic intracranial hemorrhage was not different between the two groups in the No-IVT stratum (OR 1.20 (95% CI 0.35 to 4.12)), but it was significantly higher in the EVT group than in the No-EVT group in the IVT stratum (11.5% vs 0%, p=0.03).

CONCLUSIONS

There was no difference in efficacy of EVT with or without IVT, while IVT before EVT might increase symptomatic intracranial hemorrhage in patients with large ischemic core.

TRIAL REGISTRATION INFORMATION

NCT03702413.

Understanding physician preferences about combined thrombolysis and thrombectomy in patients with large vessel occlusion: An international cross-sectional survey

BACKGROUND

A recently published individual participant-level meta-analysis found that EVT alone was not non-inferior to combined intravenous thrombolysis (IVT) and EVT. Our aim was to determine factors that influence physicians' treatment choice of IVT-alone versus EVT-alone versus a combined approach.

METHODS

We performed an international, structured, invite-only survey among physicians treating patients presenting with AIS. Respondents were asked 16 multiple choice questions. Fourteen questions involved the respondent being provided with a clinical scenario. In each scenario, a patient was presenting with an AIS with LVO, varying a single clinical or imaging feature.

RESULTS

A total of 282 stroke physicians (mean age 46 years, 75 % males) participated in the survey. In LVO stroke, eligible for both IVT and EVT, without other qualifiers, 220 (85.9 %) respondents chose to pursue a combined approach. For age over 80 years, 191 (74 %) participants opted for combined approach, which decreased to 121 (48.2 %) with dementia and 148 (57.4 %) if the patient was on dual anti-platelet therapy (DAPT). Of respondents choosing combination therapy in a patient above the age of 80, only 105 (56.8 %) would pursue the same in a patient with dementia. For imaging factors, 177 (72.8 %) opted for a combined approach for intracranial carotid occlusion, which decreased to 160 (65.3 %) in tandem occlusions. Overall, 88 (38 %) respondents agreed to the statement "I am uncomfortable with uncertainty in patient care".

CONCLUSIONS

In a typical patient with AIS due to LVO, most respondents still choose a combined revascularization approach but discrepancy in decision-making increases in complex scenarios.

Twenty-Four-Hour Post-Thrombolysis NIHSS Score As the Strongest Prognostic Predictor After Acute Ischemic Stroke: ENCHANTED Study

BACKGROUND

This study was conducted to determine optimal predictive ability of National Institutes of Health Stroke Scale (NIHSS) measurements at baseline, 24 hours, and change from baseline to 24 hours after thrombolysis on functional recovery in patients with acute ischemic stroke who participated in the ENCHANTED (Enhanced Control of Hypertension and Thrombolysis Stroke Study).

METHODS AND RESULTS

ENCHANTED was an international, multicenter, 2×2 quasifactorial, prospective, randomized open trial of low-dose versus standard-dose intravenous alteplase and intensive versus guideline-recommended blood pressure lowering in thrombolysis-eligible patients with acute ischemic stroke. Absolute (baseline minus 24 hours) and percentage (absolute change/baseline × 100) changes in NIHSS scores were calculated. Receiver operating characteristic curve analyses assessed performance of different NIHSS measurements on 90-day favorable functional recovery (modified Rankin Scale [mRS] score 0-2) and excellent functional recovery (mRS score 0-1). Youden index was used to identify optimal predictor cutoff points. A total of 4410 patients in the ENCHANTED trial were enrolled. The 24-hour NIHSS score had the highest discriminative ability for predicting favorable 90-day functional recovery (mRS score 0-2; area under the curve 0.866 versus 0.755, 0.689, 0.764; P<0.001) than baseline, absolute, and percentage change of NIHSS score, respectively. The optimal cutoff point of 24-hour NIHSS score for predicting favorable functional recovery was ≤4 (sensitivity 66.5%, specificity 87.1%, adjusted odds ratio, 9.44 [95% CI, 7.77-11.48]). The 24-hour NIHSS score (≤3) was the best predictor of 90-day excellent functional recovery (mRS score 0-1). Findings were consistent across subgroups, including sex, race, baseline NIHSS score, stroke subtype, and age.

CONCLUSIONS

In thrombolysis-eligible patients with acute ischemic stroke, 24-hour NIHSS score (optimal cutpoint of 4) is the strongest predictor of 90-day functional recovery over baseline and early change of NIHSS score.

REGISTRATION

URL: https://clinicaltrials.gov. Unique Identifier: NCT01422616.

Combined treatment of submacular hemorrhage with low-dose subretinal recombinant tissue plasminogen activator and intravitreal conbercept

BACKGROUND

Pars Plana Vitrectomy (PPV) combined with subretinal injection of low-dose recombinant tissue plasminogen activator (rt-PA) and intravitreal injection of Conbercept as a novel therapy for submacular hemorrhage (SMH) requires evaluation.

METHODS

In a retrospective interventional clinical study, 14 eyes of 14 patients with SMH underwent PPV along with rt-PA (subretinal) and Conbercept (intravitreal) injections. The main outcomes included best-corrected visual acuities (BCVAs), degrees of blood displacement, and adverse events. All patients completed at least 6-month follow-up visits.

RESULTS

Mean BCVAs significantly improved at 7 days (22.29 ± 15.35), 1 month (30.71 ± 16.42), 3 months (38.29 ± 13.72), 4 months (38.86 ± 14.15), and 6 months (41.21 ± 14.91) post-treatment compared to baseline (16.36 ± 13.97) (F = 12.89, P = 0.004). The peak improvement in BCVAs occurred at 6 months postoperatively. The procedure effectively eliminated subfoveal hemorrhages in all eyes, with clots removal and absorption occurring within one month and complete regression by 3-month follow-up visits. Postoperatively, two cases of AMD resulted in discoid scars on the fundus. No instances of rt-PA-related retinal toxicity were observed during the follow-up period.

CONCLUSION

The combined approach of PPV with low-dose rt-PA and anti-VEGF shows promise in enhancing both vision and anatomical structure in SMH therapy. Individualized treatment plans tailored to the primary disease should be developed to optimize visual prognoses.

TRIAL REGISTRATION

Retrospectively registered No.ChiCTR2100053034. Registration date: 10/11/2021.

Relationship between updated MELD and prognosis in alcohol-associated hepatitis: Opportunities for more efficient trial design

BACKGROUND

Alcohol-associated hepatitis (AH) is associated with significant mortality. Model for End-Stage Liver Disease (MELD) score is used to predict short-term mortality and aid in treatment decisions. MELD is frequently updated in the course of AH. However, once the most updated MELD is known, it is uncertain if previous ones still have prognostic value, which might be relevant for transplant allocation and trial design. We aimed to investigate the predictive performance of updated MELDs in a prospectively collected cohort of patients with AH by the InTeam consortium.

METHODS

Three hundred seven patients (with 859 MELD values within 60 d of admission) fulfilled the inclusion criteria. The main endpoint was time to death or transplant up to 90 days. We used a joint model approach to assess the predictive value of updated MELDs.

RESULTS

Updated MELD measurements had a strong prognostic value for death/transplant (HR: 1.20, 95% CI: 1.14-1.27) (p < 0.0001). Previous MELD values did not add predictive value to the most current MELD. We also showed that MELD at day 28 (MELD28) had a significant predictive value for subsequent mortality/transplant in a landmark analysis (HR: 1.18, 95% CI: 1.12-1.23). We show that the use of an ordinal scale including death, transplant, and MELD28 as a trial outcome could substantially reduce the sample size required to demonstrate short-term benefit of an intervention.

CONCLUSION

We show that updated MELDs during the trajectory of AH predict subsequent mortality or the need for transplant. MELD28 inclusion in an ordinal outcome (together with death or transplant) could increase the efficiency of randomized controlled trials.

Early REperfusion therapy with intravenous alteplase for recovery of VISION in acute central retinal artery occlusion (REVISION): Study protocol of a phase III trial

RATIONALE

Meta-analyses of case series of non-arteritic central retinal artery occlusion (CRAO) indicate beneficial effects of intravenous thrombolysis when initiated early after symptom onset. Randomized data are lacking to address this question.

AIMS

The REperfusion therapy with intravenous alteplase for recovery of VISION in acute central retinal artery occlusion (REVISION) investigates intravenous alteplase within 4.5 h of monocular vision loss due to acute CRAO.

METHODS

This study is the randomized (1:1), double-blind, placebo-controlled, multicenter adaptive phase III trial.

STUDY OUTCOMES

Primary outcome is functional recovery to normal or mildly impaired vision in the affected eye defined as best-corrected visual acuity of the Logarithm of the Minimum Angle of Resolution of 0.5 or less at 30 days (intention-to-treat analysis). Secondary efficacy outcomes include modified Rankin Score at 90 days and quality of life. Safety outcomes include symptomatic intracranial hemorrhage, major bleeding (International Society on Thrombosis and Haemostasis definition) and mortality. Exploratory analyses of optical coherence tomography/angiography, ultrasound and magnetic resonance imaging (MRI) biomarkers will be conducted.

SAMPLE SIZE

Using an adaptive design with interim analysis at 120 patients, up to 422 participants (211 per arm) would be needed for 80% power (one-sided alpha = 0.025) to detect a difference of 15%, assuming functional recovery rates of 10% in the placebo arm and 25% in the alteplase arm.

DISCUSSION

By enrolling patients within 4.5 h of CRAO onset, REVISION uses insights from meta-analyses of CRAO case series and randomized thrombolysis trials in acute ischemic stroke. Increased rates of early reperfusion and good neurological outcomes in stroke may translate to CRAO with its similar pathophysiology.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT04965038; EU Trial Number: 2023-507388-21-00.

Pharmacokinetics and pharmacodynamics of low doses of recombinant tissue plasminogen activator to establish a model for biosimilarity comparisons

Background

Recombinant tissue plasminogen activator (rt-PA) is a thrombolytic agent and essential in emergency medical care. Given recent supply shortages, the availability of biosimilar products is an urgent medical need. However, biosimilarity trials are difficult to perform in critically ill patients.

Objectives

The aim of this pilot study was to investigate the pharmacokinetics and pharmacodynamics of low rt-PA doses to establish a model for testing proposed biosimilars in healthy volunteers.

Methods

Eight healthy volunteers received 0.02 to 0.05 mg/kg rt-PA on 3 study days; blood samples were obtained every 4 minutes after the end of the bolus infusion to measure rt-PA antigen levels by enzyme immunoassay, and the pharmacodynamics were assessed with rotational thromboelastometry.

Results

Bolus infusion of low rt-PA doses was safe and well tolerated. Maximal plasma concentrations and the area under the curve increased dose-dependently. Time-concentration curves were clearly separated between the lower and the higher doses. As expected, the half-live of rt-PA was short (4.5-5 min), and representative for therapeutic doses. The intrasubject coefficient variations were moderate (<25%). Bolus infusion of rt-PA dose-dependently shortened lysis time and lysis onset time in both dose groups and caused maximum clot lysis of 100% in all participants.

Conclusion

In conclusion, the pharmacokinetics of rt-PA was dose linear and displayed limited intrasubject variability even at subtherapeutic doses. The half-life and thus clearance of rt-PA was representative of full therapeutic doses. The lysis time was shortened in a dose and time-dependent fashion and was clearly distinguishable between doses. Thus, the model appears to be suitable and sensitive to test biosimilarity.

Factors influencing the efficacy of recombinant tissue plasminogen activator: Implications for ischemic stroke treatment

Intravenous thrombolysis with a recombinant tissue plasminogen activator (rt-PA) is the first-line treatment of acute ischemic stroke. However, successful recanalization is relatively low and the underlying processes are not completely understood. The goal was to provide insights into clinically important factors potentially limiting rt-PA efficacy such as clot size, rt-PA concentration, clot age and also rt-PA in combination with heparin anticoagulant. We established a static in vitro thrombolytic model based on red blood cell (RBC) dominant clots prepared using spontaneous clotting from the blood of healthy donors. Thrombolysis was determined by clot mass loss and by RBC release. The rt-PA became increasingly less efficient for clots larger than 50 μl at a clinically relevant concentration of 1.3 mg/l. A tenfold decrease or increase in concentration induced only a 2-fold decrease or increase in clot degradation. Clot age did not affect rt-PA-induced thrombolysis but 2-hours-old clots were degraded more readily due to higher activity of spontaneous thrombolysis, as compared to 5-hours-old clots. Finally, heparin (50 and 100 IU/ml) did not influence the rt-PA-induced thrombolysis. Our study provided in vitro evidence for a clot size threshold: clots larger than 50 μl are hard to degrade by rt-PA. Increasing rt-PA concentration provided limited thrombolytic efficacy improvement, whereas heparin addition had no effect. However, the higher susceptibility of younger clots to thrombolysis may prompt a shortened time from the onset of stroke to rt-PA treatment.

Predictors of Early versus Delayed Neurological Deterioration after Thrombolysis for Ischemic Stroke

INTRODUCTION

We aimed to determine predictors of early (END) and delayed neurological deterioration (DND) and their association with the functional outcome in patients with acute ischemic stroke (AIS) who participated in the international Enhanced Control of Hypertension and Thrombolysis Stroke Study (ENCHANTED).

METHODS

END and DND (without END) were defined as scores of a ≥2-point increase on the National Institutes of Health Stroke Scale (NIHSS) or a ≥1-point decrease on the Glasgow coma scale or death, from baseline to 24 h and 24-72 h, respectively. Multivariable logistic regression models were used to determine independent predictors of END and DND and their association with 90-day outcomes (dichotomous scores on the modified Rankin scale [mRS] of 2-6 vs. 0-1 and 3-6 vs. 0-2 and death).

RESULTS

Of 4,496 patients, 871 (19.4%) and 302 (8.4%) patients experienced END and DND, respectively. Higher baseline NIHSS score, older age, large-artery occlusion due to significant atheroma, cardioembolic stroke subtype, hemorrhagic infarction and parenchymatous hematoma within 24 h were all independent predictors for both END (all p ≤ 0.01) and DND (all p ≤ 0.024). Moreover, higher baseline systolic blood pressure (BP) (odds ratio [OR] 1.07, 95% confidence interval [CI] 1.02-1.12), higher diastolic BP variability within 24 h (OR 1.07, 95% CI 1.04-1.09), patients from Asia (OR 1.25, 95% CI 1.03-1.52) were the only independent predictors for END. However, Asian ethnicity was negatively associated with DND (OR 0.64, 95% CI 0.47-0.86). Hemorrhagic infarction and parenchymatous hematoma within 24 h were the key predictors of END across all stroke subtypes. END and DND were all associated with a poor functional outcome at 90 days (all p < 0.001).

CONCLUSION

We identified overlapping and unique demographic and clinical predictors of END and DND after thrombolysis for AIS. Both END and DND predict unfavorable outcomes at 90 days.

Clinical significance of intracranial hemorrhage after thrombectomy detected solely by magnetic resonance imaging and not by computed tomography

BACKGROUND AND OBJECTIVE

Whether intracranial hemorrhage (ICH) detected using magnetic resonance imaging (MRI) affects the clinical outcomes of patients with large-vessel occlusion (LVO) treated with mechanical thrombectomy (MT) remains unclear. This study investigated the clinical features of ICH after MT detected solely by MRI.

METHODS

This was a retrospective analysis of patients with acute ischemic stroke and occlusion of the internal carotid artery or middle cerebral artery treated with MT between April 2011 and March 2021. Among 632 patients, patients diagnosed with no ICH using CT, with a pre-morbid modified Rankin Scale (mRS) score ≤ 2, and those who underwent MRI including T2* and computed tomography (CT) within 72 h from MT were enrolled. The main outcomes were the association between ICH detected solely by MRI and clinical outcomes at 90 days. Poor clinical outcomes were defined as mRS score > 2 at 90 days after onset.

RESULTS

Of the 246 patients, 29 (12%) had ICH on MRI (MRI-ICH(+)), and 217 (88%) were MRI-ICH(-). There was no significant difference between number of patients with MRI-ICH(+) experiencing poor (10 [12%]) and favorable (19 [12%]) outcomes. The mRS score at 90 days between patients with MRI-ICH (+) and MRI-ICH(-) was not significantly different (2 [1-4] vs. 2 [1-4], respectively). Higher age and lower ASPECTS were independent risk factors for poor outcomes, as shown by multivariate regression analysis. MRI-ICH(+) status was not associated with poor outcomes.

CONCLUSIONS

ICH detected by MRI alone did not influence clinical outcomes in patients with LVO treated with MT.

Comparing Low- or Standard-Dose Alteplase in Endovascular Thrombectomy: Insights From a Nationwide Registry

BACKGROUND

Timely intravenous thrombolysis and endovascular thrombectomy are the standard reperfusion treatments for large vessel occlusion stroke. Currently, it is unknown whether a low-dose thrombolytic agent (0.6 mg/kg alteplase) can offer similar efficacy to the standard dose (0.9 mg/kg alteplase).

METHODS

We enrolled consecutive patients in the multicenter Taiwan Registry of Endovascular Thrombectomy for Acute Ischemic Stroke who had received combined thrombolysis (within 4.5 hours of onset) and thrombectomy treatment from January 2019 to April 2023. The choice of low- or standard-dose alteplase was based on the physician's discretion. The outcomes included successful reperfusion (modified Thrombolysis in Cerebral Infarction score, 2b-3), symptomatic intracerebral hemorrhage, 90-day modified Rankin Scale score, and 90-day mortality. The outcomes between the 2 groups were compared using multivariable logistic regression and inverse probability of treatment weighting-adjusted analysis.

RESULTS

Among the 2242 patients in the Taiwan Registry of Endovascular Thrombectomy for Acute Ischemic Stroke, 734 (33%) received intravenous alteplase. Patients in the low-dose group (n=360) were older, had more women, more atrial fibrillation, and longer onset-to-needle time compared with the standard-dose group (n=374). In comparison to low-dose alteplase, standard-dose alteplase was associated with a lower rate of successful reperfusion (81% versus 87%; adjusted odds ratio, 0.63 [95% CI, 0.40-0.98]), a numerically higher incidence of symptomatic intracerebral hemorrhage (6.7% versus 3.9%; adjusted odds ratio, 1.81 [95% CI, 0.88-3.69]), but better 90-day modified Rankin Scale score (functional independence [modified Rankin Scale score, 0-2], 47% versus 31%; adjusted odds ratio, 1.91 [95% CI, 1.28-2.86]), and a numerically lower mortality rate (9% versus 15%; adjusted odds ratio, 0.73 [95% CI, 0.43-1.25]) after adjusting for covariates. Similar results were observed in the inverse probability of treatment weighting-adjusted models. The results were consistent across predefined subgroups and age strata.

CONCLUSIONS

Despite the lower rate of successful reperfusion and higher risk of symptomatic intracerebral hemorrhage with standard-dose alteplase, standard-dose alteplase was associated with a better functional outcome in patients receiving combined thrombolysis and thrombectomy.

Traditional Chinese Medicine formula, Sanwujiao granule, attenuates ischemic stroke by promoting angiogenesis through early administration

ETHNOPHARMACOLOGICAL RELEVANCE

Ischemic stroke (IS) is one of the most lethal diseases with the insufficient pharmacology therapeutic approach. Sanwujiao granule (SW) is widely used for IS in China with little known about its underlying mechanism.

AIM OF THE STUDY

To investigate the characteristics of therapeutic effects and potential mechanisms of SW against IS.

MATERIALS AND METHODS

The fingerprint of SW was applied by high-performance liquid chromatography-mass spectrometry (HPLC-MS). Three different drug treatment strategies, including prophylactic administration, early administration and delayed administration, were applied in rats' permanent middle cerebral occlusion (pMCAO) model. The Garcia neurological deficit test, adhesive removal test, rotarod test, TTC and TUNEL staining were performed to evaluate the pathological changes. The transcriptomic analysis was used to predict the potential mechanism of SW. The vascular deficiency model of Tg(kdrl:eGFP) zebrafish larvae and oxygen-glucose deprivation model on bEnd.3 cells were used to verify SW's pharmacological effect. qRT-PCR, immunofluorescent staining and Western Blot were applied to detect the expression of genes and proteins. The network pharmacology approach was applied to discover the potential bioactive compounds in SW that contribute to its pharmacological effect.

RESULTS

SW early and delayed administration attenuated cerebral infarction, neurological deficit and cell apoptosis. The transcriptomic analysis revealed that SW activated angiogenesis-associated biological processes specifically by early administration. CD31 immunofluorescent staining further confirmed the microvessel intensity in peri-infarct regions was significantly elevated after SW early treatment. Additionally, on the vascular deficiency model of zebrafish larvae, SW showed the angiogenesis effect. Next, the cell migration and tube formation were also observed in the bEnd.3 cells with the oxygen-glucose deprivation induced cell injury. It's worth noting that both mRNA and protein levels of angiogenesis factor, insulin-like growth factor 1, were significantly elevated in the pMCAO rats' brains treated with SW. The network pharmacology approach was applied and chasmanine, karacoline, talatisamine, etc. were probably the main active compounds of SW in IS treatment as they affected the angiogenesis-associated targets.

CONCLUSIONS

These results demonstrate that SW plays a critical role in anti-IS via promoting angiogenesis through early administration, indicating that SW is a candidate herbal complex for further investigation in treating IS in the clinical.

The effect of asymptomatic intracranial hemorrhage after mechanical thrombectomy on clinical outcome

BACKGROUND AND OBJECTIVE

Whether asymptomatic intracranial hemorrhage (ICH) affects the clinical outcomes in patients with acute large vessel occlusion treated with mechanical thrombectomy (MT) remains unclear. This study aimed to address this uncertainty.

METHODS

We retrospectively analyzed patients with acute ischemic stroke and internal carotid or middle cerebral (M1 segment) artery occlusion treated with MT between April 2011 and March 2021 at a single center. All patients had a premorbid modified Rankin scale (mRS) score ≤ 2 and an anterior circulation occlusion and underwent magnetic resonance imaging at admission. Asymptomatic ICH was defined as ICH without symptomatic ICH defined by the SITS-MOST criteria. A favorable outcome was defined as an mRS score ≤ 2 at 90 days after stroke onset.

RESULTS

Our study included 349 patients; 62% were men, the median age was 76 [67-83] years, and the median National Institutes of Health Stroke Scale (NIHSS) score was 15 [8-21]. As determined via computed tomography, 103 (30%) patients had ICH (20 symptomatic and 83 asymptomatic). The favorable outcome rate was significantly lower for asymptomatic vs. no ICH (30% vs. 67%, p < 0.01). In a multivariate regression analysis, a high NIHSS score (odds ratio [OR], 1.06; 95% confidence interval [CI], 1.02-1.10; p < 0.01) and low Alberta Stroke Program Early CT Score (OR, 0.78; 95% CI, 0.65-0.92; p < 0.01) were independent risk factors for ICH.

CONCLUSIONS

Asymptomatic ICH is associated with poor clinical outcome at 90 days after stroke onset.

Tenecteplase for Acute Ischemic Stroke Thrombolysis: Practical Considerations and Real-World Implementation

The only FDA-approved medical treatment for acute ischemic stroke (AIS) is alteplase (commonly referred to as "tPA"). The utilization of a newer fibrinolytic agent, tenecteplase, in routine stroke care is increasing because of recent clinical trial findings, streamlined clinical workflows, and cost-effectiveness. The stroke community is monitoring this development with considerable interest and special attention to the following questions: (1) Does the current evidence support superiority or noninferiority of tenecteplase compared with standard-of-care alteplase? (2) What are the ramifications of off-label treatment with tenecteplase? (3) And what are the real-world considerations when transitioning from alteplase to tenecteplase for AIS thrombolysis? This commentary provides a practical synthesis of the current evidence and discusses our institutional experience with tenecteplase including treatment considerations, off-label use, patient consent, stroke center accreditation, and cost savings. Necessary "Code Stroke" workflow changes to ensure a safe transition from alteplase to tenecteplase are detailed.

Perioperative stroke

Ischaemic or haemorrhagic perioperative stroke (that is, stroke occurring during or within 30 days following surgery) can be a devastating complication following surgery. Incidence is reported in the 0.1-0.7% range in adults undergoing non-cardiac and non-neurological surgery, in the 1-5% range in patients undergoing cardiac surgery and in the 1-10% range following neurological surgery. However, higher rates have been reported when patients are actively assessed and in high-risk populations. Prognosis is significantly worse than stroke occurring in the community, with double the 30-day mortality, greater disability and diminished quality of life among survivors. Considering the annual volume of surgeries performed worldwide, perioperative stroke represents a substantial burden. Despite notable differences in aetiology, patient populations and clinical settings, existing clinical recommendations for perioperative stroke are extrapolated mainly from stroke in the community. Perioperative in-hospital stroke is unique with respect to the stroke occurring in other settings, and it is essential to apply evidence from other settings with caution and to identify existing knowledge gaps in order to effectively guide patient care and future research.

Determining acute ischemic stroke onset time using machine learning and radiomics features of infarct lesions and whole brain

Accurate determination of the onset time in acute ischemic stroke (AIS) patients helps to formulate more beneficial treatment plans and plays a vital role in the recovery of patients. Considering that the whole brain may contain some critical information, we combined the Radiomics features of infarct lesions and whole brain to improve the prediction accuracy. First, the radiomics features of infarct lesions and whole brain were separately calculated using apparent diffusion coefficient (ADC), diffusion-weighted imaging (DWI) and fluid-attenuated inversion recovery (FLAIR) sequences of AIS patients with clear onset time. Then, the least absolute shrinkage and selection operator (Lasso) was used to select features. Four experimental groups were generated according to combination strategies: Features in infarct lesions (IL), features in whole brain (WB), direct combination of them (IW) and Lasso selection again after direct combination (IWS), which were used to evaluate the predictive performance. The results of ten-fold cross-validation showed that IWS achieved the best AUC of 0.904, which improved by 13.5% compared with IL (0.769), by 18.7% compared with WB (0.717) and 4.2% compared with IW (0.862). In conclusion, combining infarct lesions and whole brain features from multiple sequences can further improve the accuracy of AIS onset time.

Reperfusion therapy for acute ischemic stroke: where are we in 2023?

Over the last three decades, stroke care has undergone significant transformations mainly driven by the introduction of reperfusion therapy and the organization of systems of care. Patients receiving treatment through a well-structured stroke service have a much higher chance of favorable outcomes, thereby decreasing both disability and mortality. In this article, we reviewed the scientific evidence for stroke reperfusion therapy, including thrombolysis and thrombectomy, and its implementation in the public health system in Brazil.

O2L-001, an innovative thrombolytic to evacuate intracerebral haematoma

Intracerebral haemorrhage is an unmet medical need affecting more than 3 million people worldwide every year and leading to the formation of an intracerebral haematoma. Updated guidelines (2022) for the management of intracerebral haemorrhage patients recognize that minimally invasive approaches for the evacuation of supratentorial intracerebral haemorrhage have demonstrated reductions in mortality compared with medical management alone. However, improvement of functional outcome with a procedure involving thrombolytic therapy was neutral in the last large phase 3 clinical trial and requires a more effective and safer thrombolytic agent than those currently available. Here, we demonstrate that O2L-001 allows for the extended release of W253R/R275S recombinant tissue-type plasminogen activator (rtPA). A new rtPA variant, called optimized tPA (OptPA), offers improved efficacy for haematoma evacuation as well as improved safety. OptPA was produced in a Chinese hamster ovary cell line before purification, nanoprecipitation using the NANOp2Lysis® technological platform followed by suspension in a solution of 17% poloxamer 407 to obtain O2L-001. Plasmin generation assays were performed to demonstrate O2L-001 safety. Ex vivo haematoma models using human blood were used to demonstrate O2L-001 thrombolysis properties and efficacy. For the best translational significance, a clinical sized haematoma was used to ensure catheter placement and to allow administration of the thrombolytic agent into the core of the haematoma via a minimally invasive procedure. The capacity of OptPA to convert plasminogen into plasmin is strongly decreased compared to rtPA, thereby reducing potential bleeding events. However, a clot lysis assay showed that OptPA had the same fibrinolytic activity as rtPA. We demonstrated that long-term exposure to a thrombolytic agent was essential to achieve high thrombolysis efficacy. Indeed, 24 h continuous exposure to 0.1 µg/ml rtPA had similar efficacy than repeated short exposure to 30 µg/ml rtPA. This finding led to the development of O2L-001, allowing the extended release of OptPA in the first 6 h following injection. An ex vivo model using human blood was used to demonstrate O2L-001 efficacy. Interestingly, unlike rtPA, O2L-001 was able to induce the complete lysis of the 5 ml haematoma. In clinical sized haematomas (obtained from 30 ml of human blood), a single injection of O2L-001 at 1 mg/ml into the core of the haematoma led to a 44% increase in thrombolysis compared to rtPA. Taken together, these results demonstrate that O2L-001 provides new hope for haematoma evacuation and the treatment of patients with intracerebral haemorrhage.

Phage activity against Staphylococcus aureus is impaired in plasma and synovial fluid

S. aureus is a pathogen that frequently causes severe morbidity and phage therapy is being discussed as an alternative to antibiotics for the treatment of S. aureus infections. In this in vitro and animal study, we demonstrated that the activity of anti-staphylococcal phages is severely impaired in 0.5% plasma or synovial fluid. Despite phage replication in these matrices, lysis of the bacteria was slower than phage propagation, and no reduction of the bacterial population was observed. The inhibition of the phages associated with a reduction in phage adsorption, quantified to 99% at 10% plasma. S. aureus is known to bind multiple coagulation factors, resulting in the formation of aggregates and blood clots that might protect the bacterium from the phages. Here, we show that purified fibrinogen at a sub-physiological concentration of 0.4 mg/ml is sufficient to impair phage activity. In contrast, dissolution of the clots by tissue plasminogen activator (tPA) partially restored phage activity. Consistent with these in vitro findings, phage treatment did not reduce bacterial burdens in a neutropenic mouse S. aureus thigh infection model. In summary, phage treatment of S. aureus infections inside the body may be fundamentally challenging, and more investigation is needed prior to proceeding to in-human trials.

Tenecteplase, 0.4 mg/kg, in Moderate and Severe Acute Ischemic Stroke: A Pooled Analysis of NOR-TEST and NOR-TEST 2A

Background The optimal dose of tenecteplase in acute ischemic stroke remains to be defined. We present a pooled analysis of the 2 NOR-TESTs (Norwegian Tenecteplase Stroke Trials) exploring the efficacy and safety of tenecteplase, 0.4 mg/kg. Methods and Results We retrospectively reviewed 2 PROBE (Prospective Randomized Open, Blinded End-point) trials, NOR-TEST and NOR-TEST 2A. Patients were randomized to either tenecteplase, 0.4 mg/kg, or alteplase, 0.9 mg/kg. The primary end point was favorable functional outcome at 3 months (modified Rankin Scale score, 0-1) or return to baseline if prestroke modified Rankin Scale score was 2. Secondary end points included favorable functional and clinical outcome and safety data. The pooled analysis includes patients with National Institutes of Health Stroke Scale score ≥6 from both trials and an additional post hoc analysis of patients with National Institutes of Health Stroke Scale score ≤5 from NOR-TEST. The per-protocol analysis contains 483 patients, of whom 235 were assigned to tenecteplase and 248 were assigned to alteplase. In per-protocol analysis, functional outcome was better in the alteplase arm with cutoff modified Rankin Scale score of 2 (odds ratio [OR], 0.52 [95% CI, 0.33-0.80]; P=0.003) and expressed by ordinal shift analysis (OR, 1.64 [95% CI, 1.17-2.28]; P=0.004). Mortality at 3 months was higher in the tenecteplase arm (OR, 2.48 [95% CI, 1.20-5.10]; P=0.01). Mortality and intracranial hemorrhage rates were higher in the severe stroke group randomized to tenecteplase, whereas these rates were similar for alteplase and tenecteplase in moderate and mild stroke. Conclusions Tenecteplase, 0.4 mg/kg, is unsafe in moderate and severe stroke, and the risk of death and intracranial hemorrhage probably increases with stroke severity. A lower tenecteplase dose should be tested in future trials. Registration URL: https://www.clinicaltrials.gov; Unique identifiers: NCT01949948, NCT03854500.

Efficacy and safety of short-term high dosage dual antiplatelet therapy after 0.6 mg/kg rt-PA intravenous thrombolysis for acute ischemic stroke

OBJECTIVE

To evaluate the efficacy and safety of short-term high-dose of dual antiplatelet therapy after 0.6 mg/kg rt-PA intravenous thrombolysis for acute ischemic stroke (AIS).

METHODS

All 208 patients with AIS were randomized into group 1 (103 cases, after 0.6 mg/kg rt-PA, 300 mg of oral aspirin(ASP) q.d. and 225 mg of oral clopidogrel (CLO) q.d. for for 5 days, then 100 mg of oral ASP q.d. for the next 85 days and 75 mg of oral CLO q.d. for the next 16 days) and group 2 (105 cases, after 0.9 mg/kg rt-PA, 100 mg of oral ASP q.d. for 90 days and 75 mg of oral CLO q.d. for 21 days).The efficacy index was the mRS score, NIHSS score and recurrence risk of stroke, while the safety index was the incidence of bleeding events and mortality. All parameters were evaluated at 30 and 90 days after thrombolysis. Patients whose characteristics may provide the best treatment benefit were further analyzed using the logistic regression model in group 1.

RESULTS

The proportion of mRS scores between 0 and 1 in group 1 was higher than that in group 2 at both 30 days (44.7% vs 32.4%, P < .05) and 90 days (50.5% vs 35.2%, P < .05). Compared to group 2, the proportion of NIHSS scores less than 4 was significantly higher in group 1 at both 30 days (37.9% vs 25.7%, P < .05) and 90 days (46.6% vs 30.5%, P < .05). At 90 days, Group 1 had a lower stroke recurrence risk than Group 2 (3.9% vs 10.5%, P < .05). The incidence of SICH was significantly different between the 2 groups at both 30 days (2.9% vs 9.5%, P < .05) and 90 days (2.9% vs 10.5%, P < .05). However, other bleeding events and mortality rates were not significantly different between the 2 groups. The lower the baseline NIHSS score and the shorter the OTT, the more favorable the outcomes obtained at 90 days.

CONCLUSIONS

Compared to standard doses, short term high-dose dual antiplatelet therapy after 0.6 mg/kg rt-PA intravenous thrombolysis may be a good choice for AIS patients.

Effect of Jin three needles combined with Tong Qiao and blood activation Tang on neurological function, coagulation function and serum level in stroke patients

To investigate the efficacy and safety of Jin three needles combined with Tong Qiao Wu Blood-streaming Tang in patients with acute ischemic stroke (AIS), this retrospective study analyzed the data of patients with AIS between January 2017 and December 2022. The National Institutes of Health Stroke Scale (NIHSS) scores, blood neuron-specific enolase, S100β protein (S100β), fibrinogen (FIB), cerebral infarct volume, D-dimer (D-D), prothrombin time (PT), activated partial thromboplastin time, hypersensitive c-reactive protein (hs-CRP), serum tumor necrosis factor-α (TNF-α), and homocysteine (Hcy) were compared between the 2 groups. The treatment effect was significantly better in the observation group than in the comparison group (P < .05). The NIHSS score, neuron-specific enolase, S100β, and cerebral infarct volume were significantly lower in both groups after treatment than before treatment (P < .05). FIB and D-D levels were significantly lower and APTT and PT levels were significantly higher in both groups after treatment than before treatment (P < .05). TNF-α, hs-CRP, and Hcy were significantly lower in both groups after treatment than before treatment, and TNF-α, hs-CRP and Hcy were significantly lower in the observation group than in the comparison group (P < .05). No statistically significant difference in the incidence of adverse reactions occurred between the 2 groups (P > .05). Combining Jin three needles can improve the therapeutic effect in patients with AIS, promote the recovery of neurological function, improve coagulation function, and reduce the inflammatory response with good safety.

Effect of Intravenous Thrombolytic Dose of Alteplase on Long-Term Prognosis in Patients with Acute Ischemic Stroke

INTRODUCTION

This study aimed to investigate the long-term prognostic effects of different alteplase doses on patients with acute ischemic stroke (AIS).

METHODS

In this cohort study, we enrolled 501 patients with AIS treated with intravenous thrombolysis with alteplase, with the primary endpoint event of recurrence of ischemic stroke and the secondary endpoint event of death. The effects of different doses of alteplase on recurrence of ischemic stroke and death were analyzed using a Cox proportional risk model.

RESULTS

Among 501 patients with AIS treated with thrombolysis, 295 patients (58.9%) and 206 patients (41.1%) were treated with low-dose and standard-dose alteplase, respectively. During the study period, 61 patients (12.2%) had a confirmed recurrence of ischemic stroke. Multivariate Cox proportional risk analysis showed that standard-dose alteplase thrombolysis (HR 0.511, 95% CI 0.288-0.905, P = 0.021) was significantly associated with a reduced risk of long-term recurrence of AIS, whereas atrial fibrillation was associated with an increased risk of long-term recurrence of AIS. Thirty-nine (7.8%) patients died during the study period. Multivariate Cox proportional risk analysis showed that age, baseline National Institutes of Health Stroke Scale (NIHSS) score, and symptomatic steno-occlusion were associated with an increased long-term risk of death from AIS. The alteplase dose was not associated with the risk of death from AIS.

CONCLUSIONS

Standard-dose alteplase treatment reduced the risk of long-term recurrence of AIS after hospital discharge and the alteplase dose was not associated with the long-term risk of death from AIS.

Association between Rapid Ventricular Response and Stroke Outcomes in Atrial Fibrillation-Related Cardiac Embolic Stroke

INTRODUCTION

Patients with atrial fibrillation-related stroke (AF-stroke) are prone to developing rapid ventricular response (RVR). We investigated whether RVR is associated with initial stroke severity, early neurological deterioration (END) and poor outcome at 3 months.

METHODS

We reviewed patients who had AF-stroke between January 2017 and March 2022. RVR was defined as having heart rate >100 beats per minute on initial electrocardiogram. Neurological deficit was evaluated with National Institutes of Health Stroke Scale (NIHSS) score at admission. END was defined as increase of ≥2 in total NIHSS score or ≥1 in motor NIHSS score within first 72 h. Functional outcome was score on modified Rankin Scale at 3 months. Mediation analysis was performed to examine potential causal chain in which initial stroke severity may mediate relationship between RVR and functional outcome.

RESULTS

We studied 568 AF-stroke patients, among whom 86 (15.1%) had RVR. Patients with RVR had higher initial NIHSS score (p < 0.001) and poor outcome at 3 months (p = 0.004) than those without RVR. The presence of RVR [adjusted odds ratio (aOR) = 2.13; p = 0.013] was associated with initial stroke severity, but not with END and functional outcome. Otherwise, initial stroke severity [aOR = 1.27; p = <0.001] was significantly associated with functional outcome. Initial stroke severity as a mediator explained 58% of relationship between RVR and poor outcome at 3 months.

CONCLUSION

In patients with AF-stroke, RVR was independently associated with initial stroke severity but not with END and functional outcome. Initial stroke severity mediated considerable proportion of association between RVR and functional outcome.

Pathophysiology and Optimal Treatment of Intracranial Branch Atheromatous Disease

Intracranial branch atheromatous disease (BAD) is a pathological condition characterized by the occlusion of a relatively large perforating branch (700-800 µm) near the orifice of a parent artery due to atherosclerotic plaque-based thrombus (microatheroma). BAD is refractory to treatment and follows a course of progressive exacerbation, especially motor paralysis. Uniform treatment for common atherothrombotic cerebral infarction or lacunar infarction does not prevent the progressive exacerbation of BAD, and consequently affects functional prognosis. To date, various combinations of treatments have been investigated and proposed to attenuate the worsening symptoms of BAD. However, no therapy with established efficacy is yet available for BAD. Since it is the most difficult condition to treat in the area of cerebral infarction, the establishment of optimal treatment methods for BAD is keenly awaited. This review presents an overview of the acute treatments available for BAD and discusses the prospects for optimal treatment.

Best medical management versus intravenous thrombolysis for mild non-disabling ischemic stroke: A prospective noninferiority registry study

OBJECTIVES

The efficacy and safety of intravenous thrombolysis uncertain in patients with non-disabling mild ischemic stroke. Our aim was to investigate whether best medical management only is noninferior to intravenous thrombolysis plus best medical management therapy for achieving favorable functional outcome at 90 days.

MATERIALS AND METHODS

In a prospective acute ischemic stroke registry from 2018 through 2020, 314 non-disabling mild ischemic stroke patients received best medical management only and 638 underwent intravenous thrombolysis plus best medical management. The primary outcome was modified Rankin Scale ≤1 at Day 90. The noninferiority margin was -5%. Secondary outcomes of hemorrhagic transformation, early neurologic deterioration and mortality were also evaluated.

RESULTS

The best medical management only was noninferior to the combined therapy of intravenous thrombolysis and best medical management with regard to the primary outcome (unadjusted risk difference, 1.16%; 95% CI, -3.48% ∼ 5.8%; p = 0.0046 for noninferiority; adjusted risk difference, 3.01%; 95% CI, -3.39% ∼ 9.41%). After propensity score matching, p < 0.0001 for noninferiority. RD, 4.03%; 95% CI, -1.59% ∼ 9.69%. p < 0.0001 for noninferiority. Adjusted RD, 5.23%; 95% CI, -1.88% ∼ 9.97%. The occurrence of hemorrhagic transformation was significantly increased in the group of combination therapy (OR, 4.26; 95% CI, 1.30 to 13.99; p = 0.008), while no significant difference was detected in early neurologic deterioration (OR, 1.11; 95% CI, 0.49-2.52; p = 0.808) and mortality (OR, 0.57; 95% CI, 0.20 to 1.69; p = 0.214) between groups.

CONCLUSIONS

In the present study, we found the best medical management only was noninferior to the combination therapy of intravenous thrombolysis plus best medical management for non-disabling mild ischemic stroke within 4.5 h after onset. Best medical management may be a treatment of choice for non-disabling mild ischemic stroke patients. Further randomized controlled studies are warranted.

Effect of the interaction between atrial fibrillation and rt-PA dose on the prognosis of acute ischaemic stroke with intravenous thrombolysis

BACKGROUND

The association between atrial fibrillation (AF) and the prognosis of acute ischaemic stroke (AIS) remains controversial; whether the recombinant tissue plasminogen activator dose influences this association remains poorly understood.

METHODS

Patients who had an AIS were enrolled from eight stroke centres in China. According to the recombinant tissue plasminogen activator dose, patients treated with intravenous recombinant tissue plasminogen activator within 4.5 hours after symptom onset were divided into a low-dose group (recombinant tissue plasminogen activator <0.85 mg/kg) and a standard-dose group (recombinant tissue plasminogen activator ≥0.85 mg/kg). Patients who had an AIS in the low-dose group and the standard dose group were divided into whether or not they had AF. The main outcomes were major disability (modified Rankin scale (mRS) score 3-5), mortality and vascular events occurring within 3 months.

RESULTS

The study included 630 patients who received recombinant tissue plasminogen activator after AIS, including 391 males and 239 females, with a mean age of 65.8 years. Of these patients, 305 (48.4%) received low-dose recombinant tissue plasminogen activator and 325 (51.6%) received standard dose recombinant tissue plasminogen activator. The recombinant tissue plasminogen activator dose significantly influenced the association between AF and death or major disability (p-interaction=0.036). After multivariate adjustment, AF was associated with an increased risk of death or major disability (OR 2.90, 95% CI 1.47 to 5.72, p=0.002), major disability (OR 1.93, 95% CI 1.04 to 3.59, p=0.038) and vascular events (HR 5.01, 95% CI 2.25 to 11.14, p<0.001) within 3 months in patients with standard-dose recombinant tissue plasminogen activator. No significant association was found between AF and any clinical outcome in patients with low-dose recombinant tissue plasminogen activator (all p>0.05). With AF, the mRS score distribution showed a significantly worse shift in patients with standard-dose recombinant tissue plasminogen activator (p=0.016) than in those with low-dose recombinant tissue plasminogen activator (p=0.874).

CONCLUSIONS

AF may be a strong predictor of poor prognosis in patients who had an AIS receiving standard-dose recombinant tissue plasminogen activator, suggesting that low-dose recombinant tissue plasminogen activator should be administered to patients who had a stroke with AF to improve their prognosis.

WHAT IS ALREADY KNOWN ON THIS TOPIC

WHAT THIS STUDY ADDS

HOW THIS STUDY MIGHT AFFECT RESEARCH, PRACTICE OR POLICY

[Intravenous thrombolysis of ischemic stroke-Current status]

Intravenous thrombolysis (IVT) treatment with alteplase (rtPA) is an essential part of the routine treatment of patients with ischemic stroke since its introduction in the late 1990s. Rapid treatment is of essential importance. For patients with an unclear time window, various mismatch concepts have been established to identify salvageable brain tissue prior to IVT. Numerous official contraindications for rtPA are not evidence-based; for example, current data from observational studies show that systemic thrombolytic treatment is possible even in patients receiving direct oral anticoagulant (DOAC) treatment. Tenecteplase (TNK) is an alternative thrombolytic agent with some pharmacologic advantages. The most recent guidelines indicate that TNK is particularly advantageous over rtPA in patients treated in combination with endovascular stroke therapy (EST). The combination of IVT and EST should primarily be performed in the 4.5‑h time window in patients without contraindications; in the later time window EST alone is conceivable if it can be performed without delay.

Baseline brain imaging signs in patients with ischaemic stroke by the presence of atrial fibrillation: the ENCHANTED trial

BACKGROUND

We aimed to assess the association of atrial fibrillation (AF) on outcomes in a post hoc analysis of the ENCHANTED (Enhanced Control of Hypertension and Thrombolysis Stroke Study) and how this association is modified by baseline imaging features.

METHODS

Inverse probability of treatment weight was used to remove baseline imbalances between those with and without AF. The primary outcome was the modified Rankin Scale (mRS) scores at 90 days. Secondary outcomes were symptomatic intracerebral haemorrhage (sICH), early neurological deterioration or death within 24 h, and death at 90 days. The logistic regression model was used to determine the associations.

RESULTS

Of the 3285 patients included in this analysis, 636 (19%) had AF at baseline. Compared with non-AF, AF was not significantly associated with an unfavourable shift of mRS (odds ratio 1.09; 95% confidence interval, 0.96-1.24), but with sICH (2.82; 1.78-4.48; IST-3 criteria), early neurological deterioration or death within 24 h (1.31; 1.01-1.70), and death (1.42; 1.12-1.79). Among patients with acute ischaemic signs (presence, extent, swelling and attenuation of acute lesions), AF was associated with the increased risk of all the poor outcomes (all P < 0.04 for interaction).

CONCLUSIONS

We found AF increased risk of sICH, early neurological deterioration or death and death, but not unfavourable functional recovery at day 90 after thrombolysis in patients with AIS. The presence of acute ischaemic brain imaging signs at stroke presentation could be used to improve risk stratification in the presence of AF.

TRIAL REGISTRATION

The trial is registered at ClinicalTrials.gov (NCT01422616).

Treatment of Acute Stroke: Current Practices and Future Horizons

PURPOSE

This review will discuss revascularization of acute ischemic stroke (AIS), discussing the concept of the ischemic penumbra and how thrombolysis and thrombectomy take advantage of it.

SUMMARY

The goal of AIS revascularization is to rescue the ischemic penumbra and the approach to has gone from a time-based to tissue-based approach. Patients must be carefully selected for thrombolysis, which traditionally was limited to those whose last known normal time (LKNT) was known and within 4.5 h. However, newer imaging techniques involving MRI and CT perfusion (CTP) can select patients for thrombolysis whose LKNT is unknown. Alteplase, or tPA, is still the agent of choice for thrombolysis in patients with AIS but tenecteplase (TNK) may be just as effective and more efficient to use. Endovascular thrombectomy (EVT) has shown considerable efficacy for treating large-vessel occlusions and using CTP, patients can be selected for hours after symptom-onset if viable tissue remains. Further research is underway to determine if EVT can be used for medium vessel occlusions and for basilar artery thromboses as well as to determine whether an "EVT-alone" strategy is superior to "tPA + EVT" strategy.

Comparing performance measures and clinical outcomes between mobile stroke units and usual care in underserved areas

BACKGROUND

The efficacy of mobile stroke units (MSUs) in improving acute ischemic stroke (AIS) care in developing countries is unknown. We compared performance measures and stroke outcomes in AIS patients between MSU and usual care: emergency medical services (EMS) and walk-in.

METHODS

We enrolled patients > 18 years of age with an AIS within 4.5 h after onset. Demographic data, types, and time of reperfusion therapies and clinical outcomes were recorded. A favorable outcome was defined as a modified Rankin Scale (mRS) 0-2 at 3 months.

RESULTS

A total of 978 AIS patients (MSU = 243, EMS = 214, walk-in = 521) were enrolled between June 1, 2018, and April 30, 2021. The mean age (± SD) was 66 (± 14) years, and 510 (52.1%) were male. AIS time metrics were the shortest in the MSU with a mean (± SD) door to needle (DN) time of 20 (± 7), 29 (± 13), and 35 (± 16) min (p < 0.001) and door to puncture (DP) time of 73 ± 19, 86 ± 33, and 101 ± 42 min (p < 0.001) in MSU, EMS, and walk-in, respectively. Participants in the MSU (56.8%) received higher rate of reperfusion therapie(s) when compared to the EMS (51.4%) and walk-in (31.5%) (p < 0.001). After adjustment for any potential confounders and using the EMS as a reference, the MSU has the highest likelihood of achieving a favorable outcome (adjusted OR 2.15; 95% CI 1.39-3.32).

CONCLUSIONS

In underserved populations, MSUs significantly reduced DN time, increased the likelihood of receiving reperfusion treatment, and achieved independency at 3 months when compared to usual care.

Sex differences in pain expressed by patients across diverse disease states: individual patient data meta-analysis of 33,957 participants in 10 randomized controlled trials

ABSTRACT

The experience of pain is determined by many factors and has a significant impact on quality of life. This study aimed to determine sex differences in pain prevalence and intensity reported by participants with diverse disease states in several large international clinical trials. Individual participant data meta-analysis was conducted using EuroQol-5 Dimension (EQ-5D) questionnaire pain data from randomised controlled trials published between January 2000 and January 2020 and undertaken by investigators at the George Institute for Global Health. Proportional odds logistic regression models, comparing pain scores between females and males and fitted with adjustments for age and randomized treatment, were pooled in a random-effects meta-analysis. In 10 trials involving 33,957 participants (38% females) with EQ-5D pain score data, the mean age ranged between 50 and 74. Pain was reported more frequently by females than males (47% vs 37%; P < 0.001). Females also reported greater levels of pain than males (adjusted odds ratio 1.41, 95% CI 1.24-1.61; P < 0.001). In stratified analyses, there were differences in pain by disease group (P for heterogeneity <0.001), but not by age group or region of recruitment. Females were more likely to report pain, and at a higher level, compared with males across diverse diseases, all ages, and geographical regions. This study reinforces the importance of reporting sex-disaggregated analysis to identify similarities and differences between females and males that reflect variable biology and may affect disease profiles and have implications for management.

Effects of intensive blood pressure lowering on cerebral ischaemia in thrombolysed patients: insights from the ENCHANTED trial

Background

Intensive blood pressure lowering may adversely affect evolving cerebral ischaemia. We aimed to determine whether intensive blood pressure lowering altered the size of cerebral infarction in the 2196 patients who participated in the Enhanced Control of Hypertension and Thrombolysis Stroke Study, an international randomised controlled trial of intensive (systolic target 130-140 mm Hg within 1 h; maintained for 72 h) or guideline-recommended (systolic target <180 mm Hg) blood pressure management in patients with hypertension (systolic blood pressure >150 mm Hg) after thrombolysis treatment for acute ischaemic stroke between March 3, 2012 and April 30, 2018.

Methods

All available brain imaging were analysed centrally by expert readers. Log-linear regression was used to determine the effects of intensive blood pressure lowering on the size of cerebral infarction, with adjustment for potential confounders. The primary analysis pertained to follow-up computerised tomography (CT) scans done between 24 and 36 h. Sensitivity analysis were undertaken in patients with only a follow-up magnetic resonance imaging (MRI) and either MRI or CT at 24-36 h, and in patients with any brain imaging done at any time during follow-up. This trial is registered with ClinicalTrials.gov, number NCT01422616.

Findings

There were 1477 (67.3%) patients (mean age 67.7 [12.1] y; male 60%, Asian 65%) with available follow-up brain imaging for analysis, including 635 patients with a CT done at 24-36 h. Mean achieved systolic blood pressures over 1-24 h were 141 mm Hg and 149 mm Hg in the intensive group and guideline group, respectively. There was no effect of intensive blood pressure lowering on the median size (ml) of cerebral infarction on follow-up CT at 24-36 h (0.3 [IQR 0.0-16.6] in the intensive group and 0.9 [0.0-12.5] in the guideline group; log Δmean -0.17, 95% CI -0.78 to 0.43). The results were consistent in sensitivity and subgroup analyses.

Interpretation

Intensive blood pressure lowering treatment to a systolic target <140 mm Hg within several hours after the onset of symptoms may not increase the size of cerebral infarction in patients who receive thrombolysis treatment for acute ischaemic stroke of mild to moderate neurological severity.

Funding

National Health and Medical Research Council of Australia; UK Stroke Association; UK Dementia Research Institute; Ministry of Health and the National Council for Scientific and Technological Development of Brazil; Ministry for Health, Welfare, and Family Affairs of South Korea; Takeda.

Comparison of Effectiveness and Safety of Low-Dose Versus Standard-Dose Intravenous Recombinant Tissue Plasminogen Activator in Patients With Acute Ischemic Stroke: A Meta-Analysis

The aim of the present meta-analysis is to compare the efficacy and safety of low-dose and standard-dose recombinant tissue plasminogen activators (r-tPA) in patients with acute ischemic stroke. The present meta-analysis was conducted according to the Meta-Analysis of Observational Studies in Epidemiology (MOOSE) guidelines. We conducted a systematic search in PubMed, Embase, and the Cochrane Library to identify studies published between January 1, 2010, and January 31, 2023, using the following terms: "stroke," "alteplase," "doses," "efficacy," "tissue plasminogen activator," "r-tPA," and "safety." Primary efficacy outcomes included favorable outcomes (Modified Rankin Scale scores of 0-2), while secondary efficacy outcome was all-cause mortality at 90 days. Safety outcomes included asymptomatic intracerebral hemorrhage (ICH) and symptomatic ICH assessed using the National Institute of Neurological Disorders and Stroke (NINDS) study and the Safe Implementation of Thrombolysis in Stroke-Monitoring (SITS-MOST) study. We also compared parenchymal hematomas as safety outcome between the two groups defined by the authors themselves in their research. A total of 16 studies were included in the present meta-analysis. The meta-analysis did not report any significant difference between low-dose and standard-dose r-tPA in terms of mortality, symptomatic intracranial hemorrhage (SICH), asymptomatic ICH, and parenchymal hematomas. However, the favorable outcome was significantly greater in patients receiving a standard dose of r-tPA.

A comparison of low- versus standard-dose bridging alteplase in acute ischemic stroke mechanical thrombectomy using indirect methods

Background

Whether low-dose alteplase is similar to standard-dose bridging alteplase prior to endovascular mechanical thrombectomy in patients with acute ischemic stroke (AIS) remains uncertain.

Aims

The aim of this study was to compare the efficacy and safety outcomes of low- versus standard-dose bridging alteplase therapy (BT) in patients with acute ischemic stroke (AIS) who are eligible for intravenous thrombolysis (IVT) within 4.5 h after onset.

Methods

We conducted an indirect comparison of low- versus standard-dose bridging alteplase before mechanical thrombectomy in AIS of current available clinical randomized controlled trials (RCTs) that compared direct mechanical thrombectomy treatment (dMT) to BT. Primary efficacy outcomes were functional independence and excellent recovery defined as a dichotomized modified Rankin Scale (mRS) 0-2 and 0-1 at 90 days. Safety outcomes included symptomatic intracranial hemorrhage (sICH) and any intracranial hemorrhage (ICH).

Results

We included six RCTs of 2334 AIS patients in this analysis, including one trial using low-dose bridging alteplase (n = 103) and five trials using standard-dose bridging alteplase (n = 1067) against a common comparator (dMT). Indirect comparisons of low- to standard-dose bridging alteplase yielded an odds ratio (OR) of 0.84 (95% CI 0.47-1.50) for 90-day mRS 0-2, 1.18 (95% CI 0.65-2.12) for 90-day mRS 0-1, 1.21 (95% CI 0.44-3.36) for mortality, and 1.11 (95% CI 0.39-3.14) for successful recanalization. There were no significant differences in the odds for sICH (OR 1.05, 95% CI 0.32-3.41) or any ICH (OR 1.71, 95% CI 0.94-3.10) between low- and standard-dose bridging alteplase.

Conclusion

Indirect evidence shows that the effects of low- and standard-dose bridging alteplase are similar for key efficacy and safety outcomes. Due to the wide confidence intervals, larger randomized trials comparing low- and standard-dose alteplase bridging therapy are required.

Intravenous thrombolysis in acute ischemic stroke after antagonization of unfractionated heparin with protamine: case series and systematic review of literature

Background and aims

Intravenous thrombolysis (IVT) is standard of care for disabling acute ischemic stroke (AIS) within a time window of ⩽ 4.5 h. Some AIS patients cannot be treated with IVT due to limiting contraindications, including heparin usage in an anticoagulating dose within the past 24 h or an elevated activated prothrombin time (aPTT) > 15 s. Protamine is a potent antidote to unfractionated heparin.

Objectives

The objective of this study was to investigate the safety and efficacy of IVT in AIS patients after antagonization of unfractionated heparin with protamine.

Methods

Patients from our stroke center (between January 2015 and September 2021) treated with IVT after heparin antagonization with protamine were analyzed. National Institutes of Health Stroke Scale (NIHSS) was used for stroke severity and modified Rankin Scale (mRS) for outcome assessment. Substantial neurological improvement was defined as the difference between admission and discharge NIHSS of ⩾8 or discharge NIHSS of ⩽1. Good outcome at follow-up after 3 months was defined as mRS 0-2. Safety data were obtained for mortality, symptomatic intracerebral hemorrhage (sICH), and for adverse events due to protamine. Second, a systematic review was performed searching PubMed and Scopus for studies and case reviews presenting AIS patients treated with IVT after heparin antagonization with protamine. The search was limited from January 1, 2011 to September 29, 2021. Furthermore, we conducted a propensity score matching comparing protamine-treated patients to a control IVT group without protamine (ratio 2:1, match tolerance 0.2).

Results

A total of 16 patients, 5 treated in our hospital and 11 from literature, [65.2 ± 13.1 years, 37.5% female, median premorbid mRS (pmRS) 1 (IQR 1, 4)] treated with IVT after heparin antagonization using protamine were included and compared to 31 IVT patients [76.2 ± 10.9 years, 45% female, median pmRS 1 (IQR 0, 2)]. Substantial neurological improvement was evident in 68.8% of protamine-treated patients versus 38.7% of control patients (p = 0.028). Good clinical outcome at follow-up was observed in 56.3% versus 58.1% of patients (p = 0.576). No adverse events due to protamine were reported, one patient suffered sICH after secondary endovascular thrombectomy of large vessel occlusion. Mortality was 6.3% versus 22.6% (p = 0.236).

Conclusion

IVT after heparin antagonization with protamine seems to be safe and, prospectively, may extend the number of AIS patients who can benefit from reperfusion treatment using IVT. Further prospective registry trials would be helpful to further investigate the clinical applicability of heparin antagonization.

Low-dose vs. standard-dose intravenous alteplase for acute ischemic stroke with unknown time of onset

Background

Standard-dose intravenous alteplase for acute ischemic stroke (AIS) in the unknown or extended time window beyond 4.5 h after symptom onset is both effective and safe for certain patients who were selected based on multimodal neuroimaging. However, uncertainty exists regarding the potential benefit of using low-dose alteplase among the Asian population outside the 4.5-h time window.

Methods

Consecutive AIS patients who received intravenous alteplase between 4.5 and 9 h after symptom onset or with an unknown time of onset guided by multimodal computed tomography (CT) imaging were identified from our prospectively maintained database. The primary outcome was excellent functional recovery, defined as having a modified Rankin scale (mRS) score of 0-1 at 90 days. Secondary outcomes included functional independence (an mRS score of 0-2 at 90 days), early major neurologic improvement (ENI), early neurologic deterioration (END), any intracranial hemorrhage (ICH), symptomatic ICH (sICH), and 90-day mortality. Propensity score matching (PSM) and multivariable logistic regression models were used to adjust for confounding factors and compare the clinical outcomes between the low- and standard-dose groups.

Results

From June 2019 to June 2022, a total of 206 patients were included in the final analysis, of which 143 were treated with low-dose alteplase and 63 were treated with standard-dose alteplase. After accounting for confounding factors, we observed that there were no statistically significant differences between the standard- and low-dose groups with respect to excellent functional recovery [adjusted odds ratio = 1.22 (aOR), 95% confidence interval (CI): 0.62-2.39; adjusted rate difference (aRD) = 4.6%, and 95% CI: -11.2 to 20.3%]. Patients of both groups had similar rates of functional independence, ENI, END, any ICH, sICH, and 90-day mortality. In the subgroup analysis, patients aged ≥70 years were more likely to achieve excellent functional recovery when receiving standard-dose rather than low-dose alteplase.

Conclusion

The effectiveness of low-dose alteplase might be comparable to that of standard-dose alteplase in AIS patients aged <70 years with favorable perfusion-imaging profiles in the unknown or extended time window but not in those aged ≥70 years. Furthermore, low-dose alteplase did not significantly reduce the risk of sICH compared to standard-dose alteplase.

Low-dose vs. standard-dose alteplase for Chinese patients with acute ischemic stroke: A propensity score analysis

Background and purpose

Previous studies have stimulated debates on low-dose alteplase administration in acute ischemic stroke (AIS) among the Asian population. We sought to evaluate the safety and efficacy of low-dose alteplase in Chinese patients with AIS using a real-world registry.

Methods

We analyzed data from the Shanghai Stroke Service System. Patients receiving alteplase intravenous thrombolysis within 4.5 hours were included. These patients were divided into the low-dose alteplase group (0.55-0.65 mg/kg) and the standard-dose alteplase group (0.85-0.95 mg/kg). Baseline imbalances were adjusted by using the propensity score matching. The primary outcome was mortality or disability, which was defined as the modified Rankin scale (mRS) score ranging from 2 to 6 at discharge. The secondary outcomes were in-hospital mortality, symptomatic intracranial hemorrhage (sICH) and functional independence (mRS score 0-2).

Results

From January 2019 to December 2020, a total of 1,334 patients were enrolled and 368 (27.6%) were treated with low-dose alteplase. The median age of the patients was 71 years, and 38.8% were female. Our study showed that the low-dose group had significantly higher rates of death or disability (adjusted odds ratio (aOR) = 1.49, 95% confidence interval (CI) [1.12, 1.98]) and less functional independence (aOR = 0.71, 95%CI [0.52, 0.97]) than the standard-dose group. There was no significant difference in sICH or in-hospital mortality between the standard-dose and low-dose alteplase groups.

Conclusions

Low-dose alteplase was related to a poor functional outcome without lowering the risk of sICH, compared with standard-dose alteplase for AIS patients in China.

VIsion Salvage Using Intra-Ophthalmic Arterial Alteplase Combine with Nimodipine in Central Retinal Artery Occlusion (VISION)

Purpose

To investigate the efficacy and safety of selective intra-ophthalmic arterial combined nimodipine and alteplase infusion in patients with central retinal artery occlusion (CRAO).

Design

Non-randomized, prospective interventional study.

Methods

All patients with CRAO who presented at our institute within 24 hours from CRAO onset from August 2020 to July 2022 were included. Intra-arterial nimodipine and alteplase were given selectively into the ophthalmic artery. Visual acuity was recorded during and after the procedure. Change in best corrected visual acuity (BCVA) 1 month post-treatment, relative to baseline, was set as the primary outcome measure. Significant improvement in vision and adverse events are reported as secondary outcomes.

Patients

Nine patients with non-arteritic CRAO were enrolled.

Results

A total of nine patients with CRAO underwent selective intra-ophthalmic arterial nimodipine and alteplase injection. Overall, BCVA had statistically significantly improved by 0.78 logarithm of the minimum angle of resolution (logMAR) at 1 month compared with baseline (95% confidence interval: (-1.24, -0.31), p-value = 0.001). Seven (77.8%) patients had significant visual improvement (≥0.3 logMAR) at 1-month post-treatment. There were minor adverse events during administration of the nimodipine, including chemosis and headache, which resolved after the discontinuation of nimodipine. There were also asymptomatic thromboembolic events in 2 patients (22.2%) after the intervention procedure, without any morbidity or mortality.

Conclusion

The use of selective intra-ophthalmic arterial combined nimodipine and alteplase was efficacious in improving BCVA at 1 month for patients with non-arteritic CRAO presenting between 24 hours from onset, with minor adverse events but no serious adverse events.

Analyses on safety and efficacy of non-standard dose of r-tPA in intravenous thrombolysis-treated AIS patients

Background

Intravenous 0.9 mg/kg recombinant tissue plasminogen activator (r-tPA) is one of the most effective treatments in acute ischemic stroke patients. Practically, the dose of r-tPA is still a topic that is constantly being discussed.

Methods

For this observational study, data were obtained from 537 patients who received r-tPA thrombolysis at Shanghai Sixth People's Hospital stroke center over 5 years (2014–2019). Patients were divided into two groups: a non-standard dose group (0.6 mg/kg ≤ dose &lt; 0.9 mg/kg) and a standard dose group (0.9 mg/kg). Different outcomes were observed: efficacy: 3 months mRS 0-1 (3m-mRS0-1); safety: symptomatic intracranial hemorrhage within 24 h (24h-sICH) and 3 months mortality (3m-death). We also observed the effect of r-tPA dose coefficient on outcomes in different age groups and baseline National Institute of Health stroke scale (NIHSS) score subgroups.

Results

There were 265 patients who gave the standard dose treatment and 272 gave the nonstandard dose. There was no significant difference between the non-standard dose group and the standard dose group in 3m-mRS0-1, 3m-death, and 24h-sICH (p = 0.567, 0.327, and 0.415, respectively). The dose coefficient presents a significant negative correlation (p = 0.034, B = −4.290) with 3m-death in NIHSS &lt; 16 sub-group. Door-to-needle time (DNT) is the most important independent outcome-influential factor (MIOIF) in the NIHSS ≥16 sub-group. The diabetes history and baseline NIHSS score were the MIOIF in the age ≥80-year sub-group.

Conclusions

The non-standard dose group (0.6 mg/kg ≤ dose &lt; 0.9 mg/kg) shows no difference in safety and effectiveness than the standard dose group (0.9 mg/kg) in our study. The standard dose should be considered first according to current evidence and Guidelines, but the non-standard dose (0.6 mg/kg ≤ dose &lt; 0.9 mg/kg) might be an option in the actual diagnosis and treatment process considering the patient's clinical profile and financial condition.

The feasibility and accuracy of machine learning in improving safety and efficiency of thrombolysis for patients with stroke: Literature review and proposed improvements

In the treatment of ischemic stroke, timely and efficient recanalization of occluded brain arteries can successfully salvage the ischemic brain. Thrombolysis is the first-line treatment for ischemic stroke. Machine learning models have the potential to select patients who could benefit the most from thrombolysis. In this study, we identified 29 related previous machine learning models, reviewed the models on the accuracy and feasibility, and proposed corresponding improvements. Regarding accuracy, lack of long-term outcome, treatment option consideration, and advanced radiological features were found in many previous studies in terms of model conceptualization. Regarding interpretability, most of the previous models chose restrictive models for high interpretability and did not mention processing time consideration. In the future, model conceptualization could be improved based on comprehensive neurological domain knowledge and feasibility needs to be achieved by elaborate computer science algorithms to increase the interpretability of flexible algorithms and shorten the processing time of the pipeline interpreting medical images.

Effects of tissue plasminogen activator on medium-term functional independence: A propensity score-matched analysis

This study revealed the effects of tissue plasminogen activator (tPA) on medium-term functional independence in patients with stroke. We retrospectively examined 240 patients from April 2016 to March 2019 and selected 68 who met our criteria. After adjusting the functional status at the onset by propensity score matching, the functional independence measure (FIM) on admission to and discharge from the convalescent rehabilitation wards was compared between the groups classified by the presence or absence of tPA. Twelve pairs were derived by propensity score matching. Upon admission to the convalescent rehabilitation ward, the median score of the FIM was significantly higher in the tPA group than in the non-tPA group (P = .028). Patients in the tPA group had higher median FIM scores at discharge than those in the non-tPA group (P = .060). The difference in the independence level of activities of daily living (ADL) between the groups with and without tPA may gradually decrease with continuous inpatient rehabilitation. However, the tPA group tended to have high levels of independence in ADL at the time of discharge.

Machine learning prediction of symptomatic intracerebral hemorrhage after stroke thrombolysis: a cross-cultural validation in Caucasian and Han Chinese cohort

Background

Previous studies found that Asians seemed to have higher risk of HT after thrombolysis than Caucasians due to its race differences in genetic polymorphism. Whether the model developed by Caucasians could predict risk of symptomatic intracerebral hemorrhage (sICH) in Asians was unknown.

Objectives

To develop a machine learning-based model for predicting sICH after stroke thrombolysis in Caucasians and externally validate it in an independent Han Chinese cohort.

Design

The derivation Caucasian sample included 1738 ischemic stroke (IS) patients from the Virtual International Stroke Trials Archive (VISTA) data set, and the external validation Han Chinese cohort included 296 IS patients who were treated with intravenous thrombolysis.

Methods

Twenty-eight variables were collected across both samples. According to their properties, we classified them into six distinct clusters (ie, demographic variables, medical history, previous medication, baseline blood biomarkers, neuroimaging markers on initial CT scan and clinical characteristics). A support vector machine (SVM) model, which consisted of data processing, model training, testing and a 10-fold cross-validation, was developed to predict the risk of sICH after stroke thrombolysis. The receiving operating characteristic (ROC) was used to assess the prediction performance of the SVM model. A domain contribution analysis was then performed to test which cluster had the highest influence on the performance of the model.

Results

In total, 85 (4.9%) patients developed sICH in the Caucasians, and 29 (9.8%) patients developed sICH in the Han Chinese cohort. Eight features including age, NIHSS score, SBP (systolic blood pressure), DBP (diastolic blood pressure), ALP (alkaline phosphatase), ALT (alanine transaminase), glucose, and creatine level were included in the final model, all of which were from demographic, clinical characteristics, and blood biomarkers clusters, respectively. The SVM model showed a good predictive performance in both Caucasians (AUC = 0.87) and Han Chinese patients (AUC = 0.74). Domain contribution analysis showed that inclusion/exclusion of clinical characteristic cluster (NIHSS score, SBP, and DBP), had the highest influence on the performance of predicting sICH in both Caucasian and Han Chinese cohorts.

Conclusion

The established SVM model is feasible for predicting the risk of sICH after thrombolysis quickly and efficiently in both Caucasian and Han Chinese cohort.