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.

Tenecteplase for Stroke at 4.5 to 24 Hours with Perfusion-Imaging Selection.

BACKGROUND: Thrombolytic agents, including tenecteplase, are generally used within 4.5 hours after the onset of stroke symptoms. Information on whether tenecteplase confers benefit beyond 4.5 hours is limited. METHODS: We conducted a multicenter, double-blind, randomized, placebo-controlled trial involving patients with ischemic stroke to compare tenecteplase (0.25 mg per kilogram of body weight, up to 25 mg) with placebo administered 4.5 to 24 hours after the time that the patient was last known to be well. Patients had to have evidence of occlusion of the middle cerebral artery or internal carotid artery and salvageable tissue as determined on perfusion imaging. The primary outcome was the ordinal score on the modified Rankin scale (range, 0 to 6, with higher scores indicating greater disability and a score of 6 indicating death) at day 90. Safety outcomes included death and symptomatic intracranial hemorrhage. RESULTS: The trial enrolled 458 patients, 77.3% of whom subsequently underwent thrombectomy; 228 patients were assigned to receive tenecteplase, and 230 to receive placebo. The median time between the time the patient was last known to be well and randomization was approximately 12 hours in the tenecteplase group and approximately 13 hours in the placebo group. The median score on the modified Rankin scale at 90 days was 3 in each group. The adjusted common odds ratio for the distribution of scores on the modified Rankin scale at 90 days for tenecteplase as compared with placebo was 1.13 (95% confidence interval, 0.82 to 1.57; P = 0.45). In the safety population, mortality at 90 days was 19.7% in the tenecteplase group and 18.2% in the placebo group, and the incidence of symptomatic intracranial hemorrhage was 3.2% and 2.3%, respectively. CONCLUSIONS: Tenecteplase therapy that was initiated 4.5 to 24 hours after stroke onset in patients with occlusions of the middle cerebral artery or internal carotid artery, most of whom had undergone endovascular thrombectomy, did not result in better clinical outcomes than those with placebo. The incidence of symptomatic intracerebral hemorrhage was similar in the two groups. (Funded by Genentech; TIMELESS ClinicalTrials.gov number, NCT03785678.).

Therapeutic effects of Buyang Huanwu Tang combined with RT-PA intravenous thrombolysis on stroke of Qi deficiency and blood stasis type and its impact on Keap1-Nrf2/ARE pathway antioxidant stress.

This study investigated the impact of combining traditional Chinese medicine, Buyang Huanwu Tang, with intravenous thrombolysis using alteplase (rt-PA) in treating ischemic stroke patients with qi deficiency and blood stasis. A single-center clinical randomized trial involved 117 ischemic stroke patients treated with rt-PA in the neurology department from January 2019 to December 2021. Patients were randomly divided into two groups: the control group (58 patients) received rt-PA alone, while the combined group (59 patients) received rt-PA along with Buyang Huanwu Tang. Neurological deficit scores (NIHSS) were assessed before and after treatment, along with hemorheological indicators, vascular endothelial growth factor (VEGF), matrix metalloproteinase-9 (MMP-9), and Keap1-Nrf2/ARE pathway oxidative stress indicators (Keap1, Nrf2, ARE, and NQO1 proteins). Before treatment, there were no significant differences between the groups. After treatment, the combination group exhibited lower NIHSS scores at 4, 8, and 12 weeks, indicating significant improvement compared to the control group. Additionally, the combination group demonstrated reduced plasma viscosity, low and high shear viscosity, and improved red blood cell aggregation compared to the control group after 8 weeks of treatment. Furthermore, the combination group showed elevated MMP-9 levels and reduced VEGF levels, suggesting favorable outcomes. Regarding the Keap1-Nrf2/ARE pathway, Nrf2 and NQO1 protein expression levels were higher in the combination group after 8 weeks of treatment. Clinical efficacy assessment revealed that the combined treatment group had a significantly better overall treatment response. In conclusion, combining Buyang Huanwu Tang with rt-PA intravenous thrombolysis effectively mitigated oxidative stress damage in the Keap1-Nrf2/ARE pathway among ischemic stroke patients with qi deficiency and blood stasis. This approach promoted neurological function recovery and improved overall treatment outcomes.

Safety outcomes of early initiation of antithrombotic agents within 24 h after intravenous alteplase at 0.6 mg/kg.

BACKGROUND: We examined outcome of acute ischemic stroke (AIS) with administration of antithrombotics within 24 h after intravenous low-dose alteplase. METHODS: Consecutive AIS patients who were treated with intravenous alteplase at 0.6 mg/kg from 2005 to 2021 were retrospectively included in our single-center registry. Patients were classified into two groups: those who received antithrombotics within 24 h after intravenous alteplase (early initiation group) and those who did not (control group). Safety outcomes were any intracranial hemorrhage (ICH), symptomatic ICH (sICH) within 36 h after onset, and death within 3 months. sICH was defined as any ICH with a ≥ 4-point increase in the National Institutes of Health Stroke Scale (NIHSS) score or death within 36 h. RESULTS: Of 1111 patients (women, 426; median age, 76 [interquartile range, 69-83] years; median NIHSS score, 11 [6-19]; cardioembolism, 580 [52.2%]), early initiation group comprised 58 patients (22; 72 [65-80] years; 7 [4-12]; 11 [19.0%]) and control group comprised 1053 patients (404; 77 [69-84] years; 11 [6-19]; 569 [54.1%]). No significant between-group differences were observed in the incidence of any ICH (17.2% vs. 21.6%; adjusted odds ratio [aOR], 1.18; 95% confidence interval [CI], 0.57-2.44), sICH (0% vs. 0.9%, P = 1.00), or death within 3 months (5.2% vs. 6.7%; aOR, 1.23; 95% CI, 0.36-4.23). CONCLUSIONS: Early initiation of antithrombotics after intravenous alteplase at 0.6 mg/kg did not increase the rate of sICH or death within 3 months and may be used with caution in patients with advanced neurological deterioration.

Economic evaluation of intravenous alteplase for stroke with the time of onset between 4.5 and 9 hours.

BACKGROUND: A clinical trial proved the clinical effectiveness of perfusion imaging-guided intravenous thrombolysis with alteplase for patients with acute ischemic stroke (AIS) with the time of onset between 4.5 and 9 hours. This study aimed to assess the lifetime cost-effectiveness of alteplase versus placebo from the perspective of Chinese and United States (US) healthcare payers. METHODS: A decision-analytic model was built to estimate lifetime costs and quality-adjusted life-years (QALYs) associated with alteplase or placebo. Model inputs were extracted from published sources. Incremental costs, incremental QALYs, and incremental cost-effectiveness ratio (ICER) were calculated to evaluate the base-case scenario. One-way and probabilistic sensitivity analysis were performed to evaluate uncertainty in the results. RESULTS: In China, alteplase yielded an additional lifetime QALY of 0.126 with an additional cost of Chinese Yuan (¥) ¥9552 compared with placebo, and the ICER was ¥83 950 (US$12 157)/QALY. In the US, alteplase had a higher QALY (difference: 0.193) with a lower cost (difference: US$-2024) compared with placebo. In probabilistic sensitivity analyses, alteplase had a 42.54% to 78.3% probability of being cost-effective compared with placebo in China when the willingness-to-pay (WTP) threshold ranged from ¥72 447/QALY to ¥217 341/QALY. In the US, alteplase had a 93.47% to 93.57% probability of being cost-effective under the WTP threshold of US$100 000/QALY to US$150 000/QALY. These findings remained robust under one-way sensitivity analysis. CONCLUSION: For patients with AIS with a time of onset between 4.5 and 9 hours, perfusion imaging-guided intravenous alteplase was likely to be cost-effective in China and was cost-effective in the US when compared with placebo.

Tissue plasminogen activator with prolonged dwell time effectively evacuates pleural effusions.

OBJECTIVES: Fibrinolytic therapy can be effective for management of complex pleural effusions. Tissue plasminogen activator (tPA, 10 mg) and deoxyribonuclease (DNAse) every 12 h with a dwell time of one hour is a common strategy based on published data. We used a simpler protocol of tPA (4 mg) without DNAse but with a longer dwell time of 12 h, repeated daily. We reviewed our results. METHODS: Charts were reviewed and demographics, clinical data and treatment information were abstracted. Outcomes were assessed based on radiographic findings and need for surgery. RESULTS: Two hundred and fifteen effusions in 207 patients (8 bilateral) were identified. 85% were either infectious or malignant. Two hundred and forty nine chest tubes were used: 84% were 10 Fr or 12 Fr and 7% were PleurX®. Five hundred and thirty one doses of tPA were given. The median number of doses per effusion was 2 (range 1-10), and 84% of effusions were treated with three or fewer doses. There were no significant bleeding complications. Median time to chest tube removal was 6 days (range 1 to 98, IQR 4 to 10). Drainage was considered complete for 78% of effusions, while 6% required decortication. CONCLUSIONS: Low dose tPA daily with a 12 h dwell time may be as effective as the standard regimen of tPA and DNAse twice daily with one hour dwell. For most patients only three doses were required, and small pigtail catheters were sufficient. This regimen uses less medication and is logistically much easier than the current standard.

Intravenous Thrombolysis With Alteplase at 0.6 mg/kg in Patients With Ischemic Stroke Taking Direct Oral Anticoagulants.

Background We elucidated the safety of treatment with alteplase at 0.6 mg/kg within 24 hours for patients on direct oral anticoagulants (DOACs) before ischemic stroke onset. Methods and Results Consecutive patients with acute ischemic stroke who underwent intravenous thrombolysis using alteplase at 0.6 mg/kg from 2011 to 2021 were enrolled from our single-center prospective stroke registry. We compared outcomes between patients taking DOACs and those not taking oral anticoagulants within 48 hours of stroke onset. The primary safety outcome was the rate of symptomatic intracranial hemorrhage with a ≥4-point increase on the National Institutes of Health Stroke Scale score from baseline. The efficacy outcome was defined as 3-month modified Rankin Scale score of 0 to 2 after stroke onset. Of 915 patients with acute ischemic stroke who received intravenous thrombolysis (358 women; median age, 76 years; median National Institutes of Health Stroke Scale score, 10), 40 patients took DOACs (6 took dabigatran, 8 took rivaroxaban, 16 took apixaban, and 10 took edoxaban) within 24 hours of onset and 753 patients did not take any oral anticoagulants. The rate of symptomatic intracranial hemorrhage was comparable between patients on DOACs and those not on oral anticoagulants (2.5% versus 2.4%, P=0.95). The rate of favorable outcomes was comparable between the 2 groups (59.4% versus 58.2%, P=0.46), although the admission National Institutes of Health Stroke Scale score was higher in patients on DOACs. No significant differences showed in any intracranial hemorrhage within 36 hours or mortality at 3 months. Conclusions Intravenous thrombolysis would be safely performed for patients on DOACs following the recommendations of the Japanese guidelines. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02251665.

Safety and efficacy of a new modified intravenous recombinant tissue plasminogen activator (rt-PA) regimen in Chinese patients with acute ischemic stroke: A descriptive retrospective cohort study with subgroup-analysis of different rt-PA dose.

Evidence for effects of the dose of recombinant tissue plasminogen activator(rt-PA) in Asian populations is inconclusive. The standard dose may cause drug waste and increase economic burden in developing country. Therefore, we preliminarily describe the safety and efficacy of a new modified dose of rt-PA regimen(0.6 or 0.9 mg/kg, with a maximum dose of 50 mg) in real world settings. 265 consecutive patients with ischemic stroke were treated with intravenous(IV) rt-PA alone from all the 323 consecutive patients treated with reperfusion therapy between January 1, 2017 and March 31, 2020. Safety and Efficacy was assessed by early neurological improvement(ENI), early neurological deterioration(END), symptomatic intracranial hemorrhage(sICH) and 90-day outcome defined by modified Rankin scale(mRS). Subgroup analysis was conducted to draw comparisons between different dose groups ([0.5,0.6)mg/kg, [0.6,0.7)mg/kg, [0.7,0.8)mg/kg, [0.8,0.9]mg/kg). Among the 265 patients, 150(56.60%) had a favorable outcome at 3 months(3 M); Mortality occurred in 17(6.40%) in 3 M; sICH in 12(4.50%); ENI in 70(26.40%); END2 in 29(10.90%) and END4 in 18(6.80%). In subgroup analysis, there was a significant difference in sICH that more patients developed sICH in [0.8-0.9]mg/kg group(P = 0.044) in univariate analysis of different dose. After adjusting, there was no significant difference between 4 dosage groups. Significant differences were seen in gender, atrial fibrillation and baseline NIHSS in the multivariable model of favorable outcome at 3 M. Our study preliminarily shows a good safety and efficacy of our modified rt-PA regimen, indicating that this regimen should be worthy of further study especially in developing country to reduce the financial burden of patients and avoid drug waste.

Fragility Index Meta-Analysis of Randomized Controlled Trials Shows Highly Robust Evidential Strength for Benefit of <3 Hour Intravenous Alteplase.

BACKGROUND: Cumulative fragility index (FI) analysis enables quantification of the evidential strength of intravenous alteplase's core indication-treatment of disabling acute ischemic stroke within 3 hours of onset. METHODS: Meta-analyses were performed (study level) or identified (individual participant level) for freedom-from-disability (modified Rankin Scale [mRS] score 0-1, primary efficacy), functional independence (mRS score 0-2, secondary efficacy), and mortality outcomes. Individual trial and cumulative FI analyses were serially conducted after each successive randomized controlled trial (RCT). FI scores were classified as follows: not robust (FI 0-4), somewhat robust (FI 5-12), robust (FI 13-33), and highly robust (FI >33). RESULTS: Nine randomized controlled trials were identified from 1995 to 2021 of within-3-hour intravenous alteplase for acute ischemic stroke. In study-level meta-analyses, alteplase increased freedom-from-disability outcome (mRS score 0-1), 31.0% versus 22.3%, relative risk, 1.39 (95% CI, 1.20-1.61); P<0.00001; increased functional independence (mRS score 0-2), 39.7% versus 31.2%, relative risk, 1.29 (95% CI, 1.14-1.45), P<0.000; and did not alter mortality, 24.1% versus 26.1%; P=0.23. Overall FIs for study-level meta-analyses were both highly robust at 42 and 40 for mRS score 0-1 and mRS score 0-2, respectively. Serial FI analyses showed robust evidential strength for intravenous alteplase superiority with publication of the 2 NINDS-tPA trials (National Institute of Neurological Disorders and Stroke-tissue-type plasminogen activator) in 1995, increased to highly robust in 2012, and remains highly robust in 2021. CONCLUSIONS: Within-3-hour intravenous alteplase for acute ischemic stroke is one of the most robustly proven therapies in medicine. The initial concurrent trials 25 years ago showed robust evidence for benefit and, after additional studies, advanced to highly robust.

Effect of Direct Transportation to Thrombectomy-Capable Center vs Local Stroke Center on Neurological Outcomes in Patients With Suspected Large-Vessel Occlusion Stroke in Nonurban Areas: The RACECAT Randomized Clinical Trial.

Importance: In nonurban areas with limited access to thrombectomy-capable centers, optimal prehospital transport strategies in patients with suspected large-vessel occlusion stroke are unknown. Objective: To determine whether, in nonurban areas, direct transport to a thrombectomy-capable center is beneficial compared with transport to the closest local stroke center. Design, Setting, and Participants: Multicenter, population-based, cluster-randomized trial including 1401 patients with suspected acute large-vessel occlusion stroke attended by emergency medical services in areas where the closest local stroke center was not capable of performing thrombectomy in Catalonia, Spain, between March 2017 and June 2020. The date of final follow-up was September 2020. Interventions: Transportation to a thrombectomy-capable center (n = 688) or the closest local stroke center (n = 713). Main Outcomes and Measures: The primary outcome was disability at 90 days based on the modified Rankin Scale (mRS; scores range from 0 [no symptoms] to 6 [death]) in the target population of patients with ischemic stroke. There were 11 secondary outcomes, including rate of intravenous tissue plasminogen activator administration and thrombectomy in the target population and 90-day mortality in the safety population of all randomized patients. Results: Enrollment was halted for futility following a second interim analysis. The 1401 enrolled patients were included in the safety analysis, of whom 1369 (98%) consented to participate and were included in the as-randomized analysis (56% men; median age, 75 [IQR, 65-83] years; median National Institutes of Health Stroke Scale score, 17 [IQR, 11-21]); 949 (69%) comprised the target ischemic stroke population included in the primary analysis. For the primary outcome in the target population, median mRS score was 3 (IQR, 2-5) vs 3 (IQR, 2-5) (adjusted common odds ratio [OR], 1.03; 95% CI, 0.82-1.29). Of 11 reported secondary outcomes, 8 showed no significant difference. Compared with patients first transported to local stroke centers, patients directly transported to thrombectomy-capable centers had significantly lower odds of receiving intravenous tissue plasminogen activator (in the target population, 229/482 [47.5%] vs 282/467 [60.4%]; OR, 0.59; 95% CI, 0.45-0.76) and significantly higher odds of receiving thrombectomy (in the target population, 235/482 [48.8%] vs 184/467 [39.4%]; OR, 1.46; 95% CI, 1.13-1.89). Mortality at 90 days in the safety population was not significantly different between groups (188/688 [27.3%] vs 194/713 [27.2%]; adjusted hazard ratio, 0.97; 95% CI, 0.79-1.18). Conclusions and Relevance: In nonurban areas in Catalonia, Spain, there was no significant difference in 90-day neurological outcomes between transportation to a local stroke center vs a thrombectomy-capable referral center in patients with suspected large-vessel occlusion stroke. These findings require replication in other settings. Trial Registration: ClinicalTrials.gov Identifier: NCT02795962.

Effect of Intra-arterial Alteplase vs Placebo Following Successful Thrombectomy on Functional Outcomes in Patients With Large Vessel Occlusion Acute Ischemic Stroke: The CHOICE Randomized Clinical Trial.

Importance: It is estimated that only 27% of patients with acute ischemic stroke and large vessel occlusion who undergo successful reperfusion after mechanical thrombectomy are disability free at 90 days. An incomplete microcirculatory reperfusion might contribute to these suboptimal clinical benefits. Objective: To investigate whether treatment with adjunct intra-arterial alteplase after thrombectomy improves outcomes following reperfusion. Design, Setting, and Participants: Phase 2b randomized, double-blind, placebo-controlled trial performed from December 2018 through May 2021 in 7 stroke centers in Catalonia, Spain. The study included 121 patients with large vessel occlusion acute ischemic stroke treated with thrombectomy within 24 hours after stroke onset and with an expanded Treatment in Cerebral Ischemia angiographic score of 2b50 to 3. Interventions: Participants were randomized to receive intra-arterial alteplase (0.225 mg/kg; maximum dose, 22.5 mg) infused over 15 to 30 minutes (n = 61) or placebo (n = 52). Main Outcomes and Measures: The primary outcome was the difference in proportion of patients achieving a score of 0 or 1 on the 90-day modified Rankin Scale (range, 0 [no symptoms] to 6 [death]) in all patients treated as randomized. Safety outcomes included rate of symptomatic intracranial hemorrhage and death. Results: The study was terminated early for inability to maintain placebo availability and enrollment rate because of the COVID-19 pandemic. Of 1825 patients with acute ischemic stroke treated with thrombectomy at the 7 study sites, 748 (41%) patients fulfilled the angiographic criteria, 121 (7%) patients were randomized (mean age, 70.6 [SD, 13.7] years; 57 women [47%]), and 113 (6%) were treated as randomized. The proportion of participants with a modified Rankin Scale score of 0 or 1 at 90 days was 59.0% (36/61) with alteplase and 40.4% (21/52) with placebo (adjusted risk difference, 18.4%; 95% CI, 0.3%-36.4%; P = .047). The proportion of patients with symptomatic intracranial hemorrhage within 24 hours was 0% with alteplase and 3.8% with placebo (risk difference, -3.8%; 95% CI, -13.2% to 2.5%). Ninety-day mortality was 8% with alteplase and 15% with placebo (risk difference, -7.2%; 95% CI, -19.2% to 4.8%). Conclusions and Relevance: Among patients with large vessel occlusion acute ischemic stroke and successful reperfusion following thrombectomy, the use of adjunct intra-arterial alteplase compared with placebo resulted in a greater likelihood of excellent neurological outcome at 90 days. However, because of study limitations, these findings should be interpreted as preliminary and require replication. Trial Registration: ClinicalTrials.gov Identifier: NCT03876119; EudraCT Number: 2018-002195-40.

[Orolingual Angioedema after Recombinant Tissue Plasminogen Activator Treatment in Acute Cardiogenic Cerebral Embolism Patient Using Olmesartan: A Case Report].

Recombinant tissue plasminogen activator (rt-PA), which is used to treat acute cerebral infarction, may cause angioedema immediately after administration particularly in patients who are taking angiotensin-converting enzyme (ACE) inhibitors. On the other hand, unlike ACE inhibitors, angiotensin II receptor blockers (ARBs) do not act directly on bradykinin, and are therefore considered an alternative to ACE inhibitors in patients with bradykinin-related side effects. We report a case of orolingual angioedema in an 82-year-old male patient who is taking ARB, which occurred after rt-PA administration for acute cerebral infarction. The patient, who has been on medications for hypertension including ARB (olmesartan 40 mg/day) and for hyperuricemia, was transported to our hospital with the chief complaint of right conjugate deviation of the eyes and left hemiplegia. Head magnetic resonance imaging revealed cerebral infarction in the right mesencephalic artery area including the insular cortex. He was diagnosed with cardiogenic cerebral embolism, and rt-PA administration was started 4 h after onset. The patient developed eyelid edema 2.5 h after the start of administration, and orolingual angioedema and breathing difficulty 15.5 h after. The patient was treated with methylprednisolone, d-chlorpheniramine maleate, and famotidine, and the symptoms improved gradually in 1.5 h. We should pay attention to the occurrence of orolingual angioedema not only at the beginning of rt-PA administration but also for a long time thereafter when it is used in patients taking ARBs.

Underutilization of Endovascular Therapy in Black Patients With Ischemic Stroke: An Analysis of State and Nationwide Cohorts.

BACKGROUND AND PURPOSE: Endovascular therapy (EVT) is a very effective treatment but relies on specialized capabilities that are not available in every hospital where acute ischemic stroke is treated. Here, we assess whether access to and utilization of this therapy has extended uniformly across racial and ethnic groups. METHODS: We conducted a retrospective, population-based study using the 2019 Texas Inpatient Public Use Data File. Acute ischemic stroke cases and EVT use were identified using the International Classification of Diseases, Tenth Revision (ICD-10) diagnosis and procedure codes. We examined EVT utilization by race/ethnicity and performed patient- and hospital-level analyses. To validate state-specific findings, we conducted patient-level analyses using the 2017 National Inpatient Sample for national estimates. To assess independent associations between race/ethnicity and EVT, multivariable modified Poisson regressions were fitted and adjusted relative risks were estimated accounting for patient risk factors and socioeconomic characteristics. RESULTS: Among 40 814 acute ischemic stroke cases in Texas in 2019, 54% were White, 17% Black, and 21% Hispanic. Black patients had similar admissions to EVT-performing hospitals and greater admissions to comprehensive stroke centers (CSCs) compared with White patients (EVT 62% versus 62%, P=0.21; CSCs 45% versus 39%, P<0.001) but had lower EVT rates (4.1% versus 5.3%; adjusted relative risk, 0.76 [0.66-0.88]; P<0.001). There were no differences in EVT rates between Hispanic and White patients. Lower rates of EVT among Black patients were consistent in the subgroup of patients who arrived in early time windows and received intravenous recombinant tissue-type plasminogen activator (adjusted relative risk, 0.77 [0.61-0.98]; P=0.032) and the subgroup of those admitted to EVT-performing hospitals in both non-CSC (3.0% versus 5.5, P<0.001) and CSC hospitals (7.9% versus 10.4%, P<0.001) while there were no differences between Whites and Hispanic patients. Nationwide sample data confirmed this finding of lower utilization of EVT among Black patients (adjusted relative risk, 0.87 [0.77-0.98]; P=0.024). CONCLUSIONS: We found no evidence of disparity in presentation to EVT-performing hospitals or CSCs; however, lower rates of EVT were observed in Black patients.

Acute Myocardial Infarction after Intravenous Thrombolysis for Acute Ischemic Stroke: Case Series and Systematic Review.

BACKGROUND AND OBJECTIVES: Intravenous thrombolysis (IV-rtPA) has been suggested as a potential cause of myocardial infarction (MI) after acute ischemic stroke (AIS), with randomized clinical trials showing a higher number of cardiac events within the thrombolysis group. We assessed the prevalence and MI mechanisms after IV-rtPA for AIS. METHODS: Retrospective review of consecutive AIS patients admitted to six stroke units and systematic literature review searching for AIS patients who suffered a MI less than 24 h after IV-rtPA. In those with available coronary angiography, MI etiology was defined as atherosclerotic or embolic. Patients' characteristics were compared between groups. RESULTS: Fifty-two patients were included. Thirty-two patients (61.5%) derived from hospital cases, after reviewing 6958 patients treated with IV-rtPA [0.5% (95% CI 0.38-0.54) of total hospital cases]. After coronary angiography (n = 25, 48.1%), 14 (54%) patients were considered to have an atherosclerotic MI, and 11 (46%) due to coronary embolism. Patients with an embolic MI more frequently had a cardioembolic AIS (72.7% vs 28.6%; p-value = 0.047) and an intracardiac thrombus (27.3% vs 0.0%; p-value = 0.044). Although not statistically significant, patients with an embolic MI had apparent lower time intervals between starting IV-rtPA infusion and MI occurrence [2 h (0.2-3.0) vs 3 h (1.0-15.0); p-value = 0.134]. CONCLUSIONS: MI within the first 24 h after IV-rtPA for AIS is an infrequent event, and more frequently non-embolic. However, the prevalence of embolic MI was superior to what is found in the general population with MI. There was an association between the pathophysiology of AIS and MI. The low number of events and publication bias may have limited our conclusions.

Effect of Occlusion Site on the Safety and Efficacy of Intravenous Alteplase Before Endovascular Thrombectomy: A Prespecified Subgroup Analysis of DIRECT-MT.

BACKGROUND AND PURPOSE: Recent trials showed thrombectomy alone was comparable to bridging therapy in patients with anterior circulation large vessel occlusion eligible for both intravenous alteplase and endovascular thrombectomy. We performed this study to examine whether occlusion site modifies the effect of intravenous alteplase before thrombectomy. METHODS: This is a prespecified subgroup analysis of a randomized trial evaluating risk and benefit of intravenous alteplase before thrombectomy (DIRECT-MT [Direct Intra-Arterial Thrombectomy in Order to Revascularize AIS Patients With Large Vessel Occlusion Efficiently in Chinese Tertiary Hospitals]). Among 658 randomized patients, 640 with baseline occlusion site information were included. The primary outcome was the score on the modified Rankin Scale at 90 days. Multivariable ordinal logistic regression analysis with an interaction term was used to estimate treatment effect modification by occlusion location (internal carotid artery versus M1 versus M2). We report the adjusted common odds ratio for a shift toward better outcome on the modified Rankin Scale after thrombectomy alone compared with combination treatment adjusted for age, the National Institutes of Health Stroke Scale score at baseline, the time from stroke onset to randomization, the modified Rankin Scale score before stroke onset, and collateral score per the DIRECT-MT statistical analysis plan. RESULTS: The overall adjusted common odds ratio was 1.08 (95% CI, 0.82-1.43) with thrombectomy alone compared with combination treatment, and there was no significant treatment-by-occlusion site interaction (P=0.47). In subgroups based on occlusion location, we found the following adjusted common odds ratios: 0.99 (95% CI, 0.62-1.59) for internal carotid artery occlusions, 1.12 (95% CI, 0.77-1.64) for M1 occlusions, and 1.22 (95% CI, 0.53-2.79) for M2 occlusions. No treatment-by-occlusion site interactions were observed for dichotomized modified Rankin Scale distributions and successful reperfusion (extended thrombolysis in Cerebral Infarction score ≥2b) before thrombectomy. Differences in symptomatic hemorrhage rate were not significant between occlusion locations (internal carotid artery occlusion: 7.02% in bridging therapy versus 7.14% for thrombectomy alone, P=0.97; M1 occlusion: 5.06% versus 2.48%, P=0.22; M2 occlusion: 9.09% versus 4.76%; P=0.78). CONCLUSIONS: In this prespecified subgroup of a randomized trial, we found no evidence that occlusion location can inform intravenous alteplase decisions in endovascular treatment eligible patients directly presenting at endovascular treatment capable centers. Future studies are needed to confirm our findings. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03469206.

Breaking the fibrinolytic speed limit with microwheel co-delivery of tissue plasminogen activator and plasminogen.

BACKGROUND: To reestablish blood flow in vessels occluded by clots, tissue plasminogen activator (tPA) can be used; however, its efficacy is limited by transport to and into a clot and by the depletion of its substrate, plasminogen. OBJECTIVES: To overcome these rate limitations, a platform was designed to co-deliver tPA and plasminogen based on microwheels (µwheels), wheel-like assemblies of superparamagnetic colloidal beads that roll along surfaces at high speeds. METHODS: The biochemical speed limit was determined by measuring fibrinolysis of plasma clots at varying concentrations of tPA (10-800 nM) and plasminogen (1-6 µM). Biotinylated magnetic mesoporous silica nanoparticles were synthesized and bound to streptavidin-coated superparamagnetic beads to make studded beads. Studded beads were loaded with plasminogen and tPA was immobilized on their surface. Plasminogen release and tPA activity were measured on the studded beads. Studded beads were assembled into µwheels with rotating magnetic fields and fibrinolysis of plasma clots was measured in a microfluidic device. RESULTS: The biochemical speed limit for plasma clots was ~15 µm/min. Plasminogen-loaded, tPA-immobilized µwheels lyse plasma clots at rates comparableto the biochemical speed limit. With the addition of a corkscrew motion, µwheels penetrate clots, thereby exceeding the biochemical speed limit (~20 µm/min) and achieving lysis rates 40-fold higher than 50 nM tPA. CONCLUSIONS: Co-delivery of an immobilized enzyme and its substrate via a microbot capable of mechanical work has the potential to target and rapidly lyse clots that are inaccessible by mechanical thrombectomy devices or recalcitrant to systemic tPA delivery.

Endovascular Treatment for Posterior Circulation Stroke in Routine Clinical Practice: Results of the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands Registry.

BACKGROUND AND PURPOSE: The benefit of endovascular treatment (EVT) for posterior circulation stroke (PCS) remains uncertain, and little is known on treatment outcomes in clinical practice. This study evaluates outcomes of a large PCS cohort treated with EVT in clinical practice. Simultaneous to this observational study, several intervention centers participated in the BASICS trial (Basilar Artery International Cooperation Study), which tested the efficacy of EVT for basilar artery occlusion in a randomized setting. We additionally compared characteristics and outcomes of patients treated outside BASICS in trial centers to those from nontrial centers. METHODS: We included patients with PCS from the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands Registry: a prospective, multicenter, observational study of patients who underwent EVT in the Netherlands between 2014 and 2018. Primary outcome was a score of 0 to 3 on the modified Rankin Scale at 90 days. Secondary outcomes included reperfusion status and symptomatic intracranial hemorrhage. For outcome comparison between patients treated in trial versus nontrial centers, we used ordinal logistic regression analysis. RESULTS: We included 264 patients of whom 135 (51%) had received intravenous thrombolysis. The basilar artery was most often involved (77%). Favorable outcome (modified Rankin Scale score 0-3) was observed in 115/252 (46%) patients, and 109/252 (43%) patients died. Successful reperfusion was achieved in 178/238 (75%), and symptomatic intracranial hemorrhage occurred in 9/264 (3%). The 154 nontrial patients receiving EVT in BASICS trial centers had similar characteristics and outcomes as the 110 patients treated in nontrial centers (modified Rankin Scale adjusted cOR: 0.77 [95% CI, 0.5-1.2]). CONCLUSIONS: Our study shows that high rates of favorable clinical outcome and successful reperfusion can be achieved with EVT for PCS, despite high mortality. Characteristics and outcomes of patients treated in trial versus nontrial centers were similar indicating that our cohort is representative of clinical practice in the Netherlands. Randomized studies using modern treatment approaches are needed for further insight in the benefit of EVT for PCS.