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1.
Stroke ; 54(2): 632-638, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36533521

RESUMO

Randomized clinical trials of acute stroke have led to major advances in acute stroke therapy over the past decade. Despite these successes, recruitment in acute trials is often difficult. We outline challenges in recruitment for acute stroke trials and present potential solutions, which can increase the speed and decrease the cost of identifying new treatments for acute stroke. One of the largest opportunities to increase the speed of enrollment and make trials more generalizable is expansion of inclusion criteria whose impact on expected recruitment can be assessed by epidemiologic and registry databases. Another barrier to recruitment besides the number of eligible patients is availability of study investigators limited to business hours, which may be helped by financial support for after-hours call. The wider use of telemedicine has accelerated quicker stroke treatment at many hospitals and has the potential to accelerate research enrollment but requires training of clinical investigators who are often inexperienced with this approach. Other potential solutions to enhance recruitment include rapid prehospital notification of clinical investigators of potential patients, use of mobile stroke units, advances in the process of emergency informed consent, storage of study medication in the emergency department, simplification of study treatments and data collection, education of physicians to improve equipoise and enthusiasm for randomization of patients within a trial, and clear recruitment plans, and even potentially coenrollment, when there are competing trials at sites. Without successful recruitment, scientific advances and clinical benefit for acute stroke patients will lag.


Assuntos
Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/terapia , Hospitais , Consentimento Livre e Esclarecido
2.
Stroke ; 52(12): 3786-3795, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34428930

RESUMO

BACKGROUND AND PURPOSE: Evidence about the utility of ultrasound-enhanced thrombolysis (sonothrombolysis) in patients with acute ischemic stroke (AIS) is conflicting. We aimed to evaluate the safety and efficacy of sonothrombolysis in patients with AIS with large vessel occlusion, by analyzing individual patient data of available randomized-controlled clinical trials. METHODS: We included all available randomized-controlled clinical trials comparing sonothrombolysis with or without addition of microspheres (treatment group) to intravenous thrombolysis alone (control group) in patients with AIS with large vessel occlusion. The primary outcome measure was the rate of complete recanalization at 1 to 36 hours following intravenous thrombolysis initiation. We present crude odds ratios (ORs) and ORs adjusted for the predefined variables of age, sex, baseline stroke severity, systolic blood pressure, and onset-to-treatment time. RESULTS: We included 7 randomized controlled clinical trials that enrolled 1102 patients with AIS. A total of 138 and 134 confirmed large vessel occlusion patients were randomized to treatment and control groups respectively. Patients randomized to sonothrombolysis had increased odds of complete recanalization compared with patients receiving intravenous thrombolysis alone (40.3% versus 22.4%; OR, 2.17 [95% CI, 1.03-4.54]; adjusted OR, 2.33 [95% CI, 1.02-5.34]). The likelihood of symptomatic intracranial hemorrhage was not significantly different between the 2 groups (7.3% versus 3.7%; OR, 2.03 [95% CI, 0.68-6.11]; adjusted OR, 2.55 [95% CI, 0.76-8.52]). No differences in the likelihood of asymptomatic intracranial hemorrhage, 3-month favorable functional and 3-month functional independence were documented. CONCLUSIONS: Sonothrombolysis was associated with a nearly 2-fold increase in the odds of complete recanalization compared with intravenous thrombolysis alone in patients with AIS with large vessel occlusions. Further study of the safety and efficacy of sonothrombolysis is warranted.


Assuntos
AVC Isquêmico/terapia , Trombólise Mecânica/métodos , Resultado do Tratamento , Terapia por Ultrassom/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
3.
Ann Neurol ; 87(3): 419-433, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31916270

RESUMO

OBJECTIVE: The primary imaging modalities used to select patients for endovascular thrombectomy (EVT) are noncontrast computed tomography (CT) and CT perfusion (CTP). However, their relative utility is uncertain. We prospectively assessed CT and CTP concordance/discordance and correlated the imaging profiles on both with EVT treatment decisions and clinical outcomes. METHODS: A phase 2, multicenter, prospective cohort study of large-vessel occlusions presented up to 24 hours from last known well was conducted. Patients received a unified prespecified imaging evaluation (CT, CT angiography, and CTP with Rapid Processing of Perfusion and Diffusion software mismatch determination). The treatment decision, EVT versus medical management, was nonrandomized and at the treating physicians' discretion. An independent, blinded, neuroimaging core laboratory adjudicated favorable profiles based on predefined criteria (CT:Alberta Stroke Program Early CT Score ≥ 6, CTP:regional cerebral blood flow (<30%) < 70ml with mismatch ratio ≥ 1.2 and mismatch volume ≥ 10ml). RESULTS: Of 4,722 patients screened from January 2016 to February 2018, 361 patients were included. Two hundred eighty-five (79%) received EVT, of whom 87.0% had favorable CTs, 91% favorable CTPs, 81% both favorable profiles, 16% discordant, and 3% both unfavorable. Favorable profiles on the 2 modalities correlated similarly with 90-day functional independence rates (favorable CT = 56% vs favorable CTP = 57%, adjusted odds ratio [aOR] = 1.91, 95% confidence interval [CI] = 0.40-9.01, p = 0.41). Having a favorable profile on both modalities significantly increased the odds of receiving thrombectomy as compared to discordant profiles (aOR = 3.97, 95% CI = 1.97-8.01, p < 0.001). Fifty-eight percent of the patients with favorable profiles on both modalities achieved functional independence as compared to 38% in discordant profiles and 0% when both were unfavorable (p < 0.001 for trend). In favorable CT/unfavorable CTP profiles, EVT was associated with high symptomatic intracranial hemorrhage (sICH) (24%) and mortality (53%) rates. INTERPRETATION: Patients with favorable imaging profiles on both modalities had higher odds of receiving EVT and high functional independence rates. Patients with discordant profiles achieved reasonable functional independence rates, but those with an unfavorable CTP had higher adverse outcomes. Ann Neurol 2020;87:419-433.


Assuntos
Procedimentos Endovasculares/métodos , Acidente Vascular Cerebral/cirurgia , Tomografia Computadorizada por Raios X/métodos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neuroimagem , Seleção de Pacientes , Estudos Prospectivos , Método Simples-Cego , Trombectomia/métodos , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Resultado do Tratamento
4.
Semin Neurol ; 41(1): 16-27, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33472270

RESUMO

Acute ischemic stroke (AIS) is a time sensitive medical emergency and a leading cause of morbidity and mortality worldwide. Intravenous (IV) recombinant tissue plasminogen activator (IV alteplase) is currently the only proven effective medication for the treatment of AIS with promising adjuvant medications currently under investigation. Recent advances in endovascular thrombectomy have broadened therapeutic options in specific patient populations, with modern treatment strategies utilizing advanced imaging modalities to extend the window for treatment. In all cases, rapid treatment remains a priority. The future of IV alteplase and the changing standard for treatment of AIS remain unwritten with the increasing evidence for imaging selection for both endovascular thrombectomy and IV alteplase, while novel adjuncts are under investigation. In this article, we review the history of IV alteplase investigations for stroke, evidence for thrombectomy as an adjunct to IV alteplase, and the potential of novel adjuvant therapeutics currently under investigation.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/tratamento farmacológico , Fibrinolíticos/uso terapêutico , Humanos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/tratamento farmacológico , Trombectomia , Ativador de Plasminogênio Tecidual , Resultado do Tratamento
5.
Stem Cells ; 37(11): 1481-1491, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31529663

RESUMO

Cellular therapy is a promising investigational modality to enhance poststroke recovery. We conducted a single-arm, phase I clinical trial to determine the safety and feasibility of intravenous (IV) administration of autologous bone marrow mononuclear cells (MNCs) after acute ischemic stroke (AIS). Patients with moderate severity of AIS underwent bone marrow harvest followed by IV reinfusion of MNCs within 24-72 hours of onset. A target dose of 10 million cells per kilogram was chosen based on preclinical data. Patients were followed up daily during hospitalization and at 1, 3, 6, 12, and 24 months for incidence of adverse events using laboratory, clinical (12 months), and radiological (24 months) parameters. The trial was powered to detect severe adverse events (SAEs) with incidences of at least 10% and planned to enroll 30 patients. Primary outcomes were study-related SAEs and the proportion of patients successfully completing study intervention. A propensity score-based matched control group was used for the estimation of effect size (ES) for day-90 modified Rankin score (mRS). There were no study-related SAEs and, based on a futility analysis, enrolment was stopped after 25 patients. All patients successfully completed study intervention and most received the target dose. Secondary analysis estimated the ES to be a reduction of 1 point (95% confidence interval: 0.33-1.67) in median day-90 mRS for treated patients as compared with the matched control group. Bone marrow harvest and infusion of MNCs is safe and feasible in patients with AIS. The estimated ES is helpful in designing future randomized controlled trials. Stem Cells 2019;37:1481-1491.


Assuntos
Células da Medula Óssea/citologia , Transplante de Medula Óssea/efeitos adversos , Isquemia Encefálica/terapia , Leucócitos Mononucleares/citologia , Acidente Vascular Cerebral/terapia , Administração Intravenosa , Idoso , Células da Medula Óssea/fisiologia , Transplante de Medula Óssea/métodos , Isquemia Encefálica/diagnóstico por imagem , Imagem de Tensor de Difusão , Estudos de Viabilidade , Feminino , Humanos , Leucócitos Mononucleares/fisiologia , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/diagnóstico por imagem , Resultado do Tratamento
6.
J Stroke Cerebrovasc Dis ; 27(12): 3647-3651, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30249518

RESUMO

BACKGROUND: A randomized trial of concurrent recombinant tissue-type plasminogen activator (r-tPA) + thrombin-inhibition with Argatroban in stroke patients recently demonstrated safety and signal of efficacy compared to r-tPA alone, but patients having endovascular therapy (EVT) were excluded. The current study intended to study feasibility and safety of concurrent r-tPA and Argatroban in patients undergoing EVT. METHODS: We conducted a single-arm, feasibility, and safety study of patients that received standard-dose r-tPA, had intracranial large vessel occlusions, and underwent EVT within 6 hours of stroke onset. During r-tPA, a 100 µg/kg Argatroban bolus, followed by 12-hour infusion, targeted an activated Partial Thromboplastin Time (aPTT) 2.25 timesbaseline. Feasibility was defined as ability to combine treatments without EVT time-metric delays, compared to cotemporaneous r-tPA + EVT treatments. Safety was incidence of symptomatic intracerebral hemorrhage (sICH), systemic hemorrhage, or EVT complications. RESULTS: All preplanned 10 patients were enrolled. Arterial occlusions were middle cerebral artery (n = 8), internal carotid artery (n = 1), and posterior cerebral artery (n = 1). All received Argatroban before EVT and completed infusions. There were no delays in time-metrics compared to nonstudy patients during the same period. Nine patients achieved excellent angiographic reperfusion (Thrombolysis In Cerebral Ischemia [TICI] ≥2b); with 7 complete (TICI = 3). There were no sICH, systemic hemorrhage, or EVT complications. At 90 days, 6 (60%) patients had a modified Rankin Scale of 0-2 and none died. CONCLUSIONS: In patients treated with r-tPA and EVT, concomitant Argatroban is feasible, does not delay EVT provision, produces high rates of recanalization, is probably safe, and warrants further study.


Assuntos
Procedimentos Endovasculares , Fibrinolíticos/uso terapêutico , Ácidos Pipecólicos/uso terapêutico , Inibidores da Agregação Plaquetária/uso terapêutico , Acidente Vascular Cerebral/terapia , Ativador de Plasminogênio Tecidual/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Arginina/análogos & derivados , Hemorragia Cerebral/epidemiologia , Terapia Combinada , Quimioterapia Combinada , Procedimentos Endovasculares/efeitos adversos , Estudos de Viabilidade , Fibrinolíticos/efeitos adversos , Humanos , Incidência , Pessoa de Meia-Idade , Ácidos Pipecólicos/efeitos adversos , Inibidores da Agregação Plaquetária/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Sulfonamidas , Terapia Trombolítica/efeitos adversos , Ativador de Plasminogênio Tecidual/efeitos adversos , Resultado do Tratamento
7.
Stroke ; 48(6): 1608-1616, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28507269

RESUMO

BACKGROUND AND PURPOSE: We conducted a randomized exploratory study to assess safety and the probability of a favorable outcome with adjunctive argatroban, a direct thrombin-inhibitor, administered to recombinant tissue-type plasminogen activator (r-tPA)-treated ischemic stroke patients. METHODS: Patients treated with standard-dose r-tPA, not receiving endovascular therapy, were randomized to receive no argatroban or argatroban (100 µg/kg bolus) followed by infusion of either 1 (low dose) or 3 µg/kg per minute (high dose) for 48 hours. Safety was incidence of symptomatic intracerebral hemorrhage. Probability of clinical benefit (modified Rankin Scale score 0-1 at 90 days) was estimated using a conservative Bayesian Poisson model (neutral prior probability centered at relative risk, 1.0 and 95% prior intervals, 0.33-3.0). RESULTS: Ninety patients were randomized: 29 to r-tPA alone, 30 to r-tPA+low-dose argatroban, and 31 to r-tPA+high-dose argatroban. Rates of symptomatic intracerebral hemorrhage were similar among control, low-dose, and high-dose arms: 3/29 (10%), 4/30 (13%), and 2/31 (7%), respectively. At 90 days, 6 (21%) r-tPA alone, 9 (30%) low-dose, and 10 (32%) high-dose patients were with modified Rankin Scale score 0 to 1. The relative risks (95% credible interval) for modified Rankin Scale score 0 to 1 with low, high, and either low or high dose argatroban were 1.17 (0.57-2.37), 1.27 (0.63-2.53), and 1.34 (0.68-2.76), respectively. The probability that adjunctive argatroban was superior to r-tPA alone was 67%, 74%, and 79% for low, high, and low or high dose, respectively. CONCLUSIONS: In patients treated with r-tPA, adjunctive argatroban was not associated with increased risk of symptomatic intracerebral hemorrhage and provides evidence that a definitive effectiveness trial is indicated. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique Identifier: NCT01464788.


Assuntos
Antitrombinas/farmacocinética , Isquemia Encefálica/tratamento farmacológico , Hemorragia Cerebral/induzido quimicamente , Fibrinolíticos/farmacologia , Avaliação de Resultados em Cuidados de Saúde , Ácidos Pipecólicos/farmacologia , Índice de Gravidade de Doença , Acidente Vascular Cerebral/tratamento farmacológico , Ativador de Plasminogênio Tecidual/farmacologia , Idoso , Idoso de 80 Anos ou mais , Antitrombinas/administração & dosagem , Antitrombinas/efeitos adversos , Arginina/análogos & derivados , Quimioterapia Combinada , Feminino , Fibrinolíticos/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Ácidos Pipecólicos/administração & dosagem , Ácidos Pipecólicos/efeitos adversos , Sulfonamidas , Ativador de Plasminogênio Tecidual/administração & dosagem
8.
Ann Neurol ; 80(2): 211-8, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27273860

RESUMO

OBJECTIVE: It is estimated that one of four ischemic strokes are noticed upon awakening and are not candidates for intravenous recombinant tissue plasminogen activator (rtPA) because their symptoms are >3 hours from last seen normal (LSN). We tested the safety of rtPA in a multicenter, single-arm, prospective, open-label study (NCT01183533) in patients with wake-up stroke (WUS). METHODS: We aimed to enroll 40 WUS patients with disabling deficits. Patients were 18 to 80 years of age, National Institutes of Health Stroke Scale (NIHSS) ≤25, and selected only on the appearance of noncontrast computed tomography (ie, over one-third middle cerebral artery territory hypodensity). Standard-dose (0.9mg/kg) intravenous rtPA had to be started ≤3 hours of patient awakening. The primary safety outcome was symptomatic intracerebral hemorrhage (sICH) with preplanned stopping rules and data safety board oversight. Other endpoints included: asymptomatic intracerebral hemorrhage; clinical improvement in NIHSS; and 90-day modified Rankin Scale (mRS) score. RESULTS: Between October 2010 and October 2013, all 40 preplanned patients were enrolled (50% men) at five stroke centers. Four patients (10%) were subsequently determined to be mimics. Patients had a mean age of 60.8, median NIHSS of 6.5 (range, 2-24), and received thrombolysis at a mean time of 10.3 ± 2.6 LSN and 2.6 ± 0.6 hours from awakening with deficits. No sICH or parenchymal hematomas occurred. At 3 months, 20 of 38 (52.6%) patients achieved excellent recovery with mRS scores of 0 or 1 (2 patients were lost to follow-up). INTERPRETATION: Intravenous thrombolysis was safe in this prospective WUS study of patients selected by noncontrast CT. A randomized effectiveness trial appears feasible using a similar, pragmatic design. Ann Neurol 2016;80:211-218.


Assuntos
Hemorragia Cerebral/induzido quimicamente , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Acidente Vascular Cerebral/tratamento farmacológico , Ativador de Plasminogênio Tecidual/administração & dosagem , Ativador de Plasminogênio Tecidual/efeitos adversos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Fibrinolíticos/administração & dosagem , Fibrinolíticos/efeitos adversos , Fibrinolíticos/uso terapêutico , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/uso terapêutico , Índice de Gravidade de Doença , Fatores de Tempo , Ativador de Plasminogênio Tecidual/uso terapêutico , Resultado do Tratamento , Adulto Jovem
10.
Stroke ; 46(8): 2238-43, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26138130

RESUMO

BACKGROUND AND PURPOSE: Although the modified Rankin Scale (mRS) is the most commonly used primary end point in acute stroke trials, its power is limited when analyzed in dichotomized fashion and its indication of effect size challenging to interpret when analyzed ordinally. Weighting the 7 Rankin levels by utilities may improve scale interpretability while preserving statistical power. METHODS: A utility-weighted mRS (UW-mRS) was derived by averaging values from time-tradeoff (patient centered) and person-tradeoff (clinician centered) studies. The UW-mRS, standard ordinal mRS, and dichotomized mRS were applied to 11 trials or meta-analyses of acute stroke treatments, including lytic, endovascular reperfusion, blood pressure moderation, and hemicraniectomy interventions. RESULTS: Utility values were 1.0 for mRS level 0; 0.91 for mRS level 1; 0.76 for mRS level 2; 0.65 for mRS level 3; 0.33 for mRS level 4; 0 for mRS level 5; and 0 for mRS level 6. For trials with unidirectional treatment effects, the UW-mRS paralleled the ordinal mRS and outperformed dichotomous mRS analyses. Both the UW-mRS and the ordinal mRS were statistically significant in 6 of 8 unidirectional effect trials, whereas dichotomous analyses were statistically significant in 2 to 4 of 8. In bidirectional effect trials, both the UW-mRS and ordinal tests captured the divergent treatment effects by showing neutral results, whereas some dichotomized analyses showed positive results. Mean utility differences in trials with statistically significant positive results ranged from 0.026 to 0.249. CONCLUSIONS: A UW-mRS performs similar to the standard ordinal mRS in detecting treatment effects in actual stroke trials and ensures the quantitative outcome is a valid reflection of patient-centered benefits.


Assuntos
Ensaios Clínicos como Assunto/métodos , Assistência Centrada no Paciente/métodos , Índice de Gravidade de Doença , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/terapia , Ensaios Clínicos como Assunto/normas , Humanos , Assistência Centrada no Paciente/normas , Acidente Vascular Cerebral/diagnóstico , Resultado do Tratamento
12.
Ann Neurol ; 73(6): 721-8, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23418024

RESUMO

OBJECTIVE: Chronic cerebrospinal venous insufficiency (CCSVI) has been implicated in the pathophysiology of multiple sclerosis (MS). We sought to determine whether neurosonography (NS) provides reliable information on cerebral venous outflow patterns specific to MS. METHODS: This was a single-center, prospective case-control study of volunteer MS and non-MS participants. A neurosonologist, blind to the subjects' diagnosis, used high-resolution B-mode imaging with color and spectral Doppler to systematically investigate, capture, and record extracranial and intracranial venous drainage. These neuroimaging results were evaluated and scored by an expert blinded to subjects' information and with no interactions with the participants. RESULTS: Altogether, 276 subjects were studied: 206 with MS and 70 non-MS. MS patients were older than non-MS subjects (48.3±9.9 vs 44.3±11.8 years, p<0.007), with durations from first symptoms and diagnosis of 13.7±10 and 9.9±7.8 years, and Expanded Disability Status Scale of 2.6±2.0. Overall, 82 subjects (29.7%) fulfilled 1 of 5 NS criteria proposed for CCSVI; 13 (4.7%) fulfilled 2 criteria required for diagnosis, and none fulfilled >2 criteria. The distribution of subjects with 0, 1, or 2 criteria did not differ significantly across all diagnostic groupings, between MS and non-MS subjects, or within MS subgroups. CCSVI was present in 7.14% of non-MS and 3.88% of MS patients (p=0.266). No significant differences emerged between MS and non-MS subjects for extracranial or intracranial venous flow rates. INTERPRETATION: NS findings described as CCSVI are much less prevalent than initially reported, and do not distinguish MS from other subjects. Our findings do not support the hypothesis that CCSVI is causally associated with MS.


Assuntos
Veias Cerebrais/diagnóstico por imagem , Esclerose Múltipla/diagnóstico por imagem , Medula Espinal/irrigação sanguínea , Medula Espinal/diagnóstico por imagem , Ultrassonografia Doppler em Cores/métodos , Insuficiência Venosa/diagnóstico por imagem , Adulto , Estudos de Casos e Controles , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/epidemiologia , Neuroimagem/métodos , Estudos Prospectivos , Método Simples-Cego , Ultrassonografia Doppler Transcraniana , Insuficiência Venosa/epidemiologia
13.
J Magn Reson Imaging ; 40(3): 630-40, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24273083

RESUMO

PURPOSE: To demonstrate the efficacy of contrast enhanced magnetic resonance venography (CEMRV) using gadofosveset trisodium in the comprehensive evaluation of the intracranial and extracranial venous system. MATERIALS AND METHODS: Temporal signal decay, in-plane saturation and flow artifacts were assessed in an institutional review board approved, HIPAA compliant CEMRV study of 99 subjects. In a 39 subject subset, percent diameter narrowing of the internal jugular (IJ), brachiocephalic and azygous veins were coded according to the following ordinal grades for both catheter venography (CV) and CEMRV: grade 0 ≤ 50%, grade 1 >50% and ≤ 75%, grade 2 >75% and <100% and grade 3 = 100% and compared with pressure gradient measurements obtained during CV. RESULTS: There was no significant signal decay, in-plane saturation or flow artifacts identified on CEMRV or hemodynamically significant pressure gradients identified on CV. All brachiocephalic and azygous veins had matched grade 0 narrowing on both modalities. Discrepancy between modalities occurred in the IJ veins at the level of thyroid gland where 15% of IJ veins had CEMRV grade ≥ 1 narrowing compared with 4% for CV or below the thyroid gland where 5% of IJ veins had CEMRV grade ≥ 1 narrowing compared with 20% for CV. There was fair agreement (κ = 0.24) between modalities for grade of narrowing in the combined data set of all coded veins. CONCLUSION: CEMRV using gadofosveset trisodium is accurate in the evaluation of the venous system.


Assuntos
Gadolínio , Angiografia por Ressonância Magnética/métodos , Compostos Organometálicos , Veias/anatomia & histologia , Adulto , Artefatos , Circulação Cerebrovascular , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/patologia , Estudos Prospectivos , Sensibilidade e Especificidade , Veias/patologia
14.
Stroke ; 44(6): 1641-6, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23598523

RESUMO

BACKGROUND AND PURPOSE: We aimed to evaluate safety and tolerability of a novel operator-independent ultrasound device among stroke-free volunteers. METHODS: A headframe containing 18 ultrasound transducers (each operating at 2 MHz, pulsed-wave) was used to expose both temporal windows and the suboccipital window. The transmission characteristics were set to emulate the acoustic characteristics of the exposure levels in the Combined Lysis of Thrombus in Brain Ischemia using Transcranial Ultrasound and Systemic tPA (CLOTBUST) trial and to never exceed Food and Drug Administration mandated diagnostic ultrasound exposure limits. Volunteers underwent 2 hours of insonation with transducer activation one at a time. Safety was captured using serial neurological examinations and pre- and postinsonation MRI for detection of the blood brain barrier permeability. RESULTS: A total of 15 volunteers (40% men; 49 ± 16 years; 27% black; all pre-exposure National Institutes of Health Stroke Scale scores 0) were enrolled. Five volunteers received pulsed-wave ultrasound via the best pair temporal transducers, 5 via sequential activation of the suboccipital transducers, and 5 via sequential activation of all bilateral temporal and suboccipital transducers. All subjects were safely insonated with no adverse effects as indicated by the neurological examinations during, immediately after the exposure, and at 24 hours, and no abnormality of the blood brain barrier was found on any of the MRIs. CONCLUSIONS: Our novel device was well tolerated by stroke-free volunteers and did not cause any neurological dysfunction nor did it affect blood brain barrier integrity. The safety and efficacy of the device are now being tested in stroke patients receiving intravenous tissue-type plasminogen activator in phase II-III clinical trials.


Assuntos
Trombose Intracraniana/terapia , Acidente Vascular Cerebral/terapia , Terapia Trombolítica/instrumentação , Terapia por Ultrassom/instrumentação , Adulto , Idoso , Barreira Hematoencefálica/patologia , Encéfalo/patologia , Segurança de Equipamentos , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Trombólise Mecânica/instrumentação , Trombólise Mecânica/métodos , Pessoa de Meia-Idade , Terapia Trombolítica/métodos , Terapia por Ultrassom/métodos
15.
Stroke ; 44(12): 3376-81, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24159060

RESUMO

BACKGROUND AND PURPOSE: The Combined Lysis of Thrombus in Brain Ischemia With Transcranial Ultrasound and Systemic T-PA-Hands-Free (CLOTBUST-HF) study is a first-in-human, National Institutes of Health-sponsored, multicenter, open-label, pilot safety trial of tissue-type plasminogen activator (tPA) plus a novel operator-independent ultrasound device in patients with ischemic stroke caused by proximal intracranial occlusion. METHODS: All patients received standard-dose intravenous tPA, and shortly after tPA bolus, the CLOTBUST-HF device delivered 2-hour therapeutic exposure to 2-MHz pulsed-wave ultrasound. Primary outcome was occurrence of symptomatic intracerebral hemorrhage. All patients underwent pretreatment and post-treatment transcranial Doppler ultrasound or CT angiography. National Institutes of Health Stroke Scale scores were collected at 2 hours and modified Rankin scale at 90 days. RESULTS: Summary characteristics of all 20 enrolled patients were 60% men, mean age of 63 (SD=14) years, and median National Institutes of Health Stroke Scale of 15. Sites of pretreatment occlusion were as follows: 14 of 20 (70%) middle cerebral artery, 3 of 20 (15%) terminal internal carotid artery, and 3 of 20 (15%) vertebral artery. The median (interquartile range) time to tPA at the beginning of sonothrombolysis was 22 (13.5-29.0) minutes. All patients tolerated the entire 2 hours of insonation, and none developed symptomatic intracerebral hemorrhage. No serious adverse events were related to the study device. Rates of 2-hour recanalization were as follows: 8 of 20 (40%; 95% confidence interval, 19%-64%) complete and 2 of 20 (10%; 95% confidence interval, 1%-32%) partial. Middle cerebral artery occlusions demonstrated the greatest complete recanalization rate: 8 of 14 (57%; 95% confidence interval, 29%-82%). At 90 days, 5 of 20 (25%, 95% confidence interval, 7%-49) patients had a modified Rankin scale of 0 to 1. CONCLUSIONS: Sonothrombolysis using a novel, operator-independent device, in combination with systemic tPA, seems safe, and recanalization rates warrant evaluation in a phase III efficacy trial. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: CLOTBUST-HF NCT01240356.


Assuntos
Isquemia Encefálica/terapia , Fibrinolíticos/uso terapêutico , Acidente Vascular Cerebral/terapia , Terapia Trombolítica/instrumentação , Ativador de Plasminogênio Tecidual/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/tratamento farmacológico , Terapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/tratamento farmacológico , Terapia Trombolítica/efeitos adversos , Resultado do Tratamento , Ultrassonografia Doppler Transcraniana/efeitos adversos , Ultrassonografia Doppler Transcraniana/instrumentação
16.
Stroke ; 44(12): 3324-30, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23929748

RESUMO

BACKGROUND AND PURPOSE: Intra-arterial therapy (IAT) promotes recanalization of large artery occlusions in acute ischemic stroke. Despite high recanalization rates, poor clinical outcomes are common. We attempted to optimize a score that combines clinical and imaging variables to more accurately predict poor outcome after IAT in anterior circulation occlusions. METHODS: Patients with acute ischemic stroke undergoing IAT at University of Texas (UT) Houston for large artery occlusions (middle cerebral artery or internal carotid artery) were reviewed. Independent predictors of poor outcome (modified Rankin Scale, 4-6) were studied. External validation was performed on IAT-treated patients at Emory University. RESULTS: A total of 163 patients were identified at UT Houston. Independent predictors of poor outcome (P≤0.2) were identified as score variables using sensitivity analysis and logistic regression. Houston Intra-Arterial Therapy 2 (HIAT2) score ranges 0 to 10: age (≤59=0, 60-79=2, ≥80 years=4), glucose (<150=0, ≥150=1), National Institute Health Stroke Scale (≤10=0, 11-20=1, ≥21=2), the Alberta Stroke Program Early CT Score (8-10=0, ≤7=3). Patients with HIAT2≥5 were more likely to have poor outcomes at discharge (odds ratio, 6.43; 95% confidence interval, 2.75-15.02; P<0.001). After adjusting for reperfusion (Thrombolysis in Cerebral Infarction score≥2b) and time from symptom onset to recanalization, HIAT2≥5 remained an independent predictor of poor outcome (odds ratio, 5.88; 95% confidence interval, 1.96-17.64; P=0.02). Results from the cohort of Emory (198 patients) were consistent; patients with HIAT2 score≥5 had 6× greater odds of poor outcome at discharge and at 90 days. HIAT2 outperformed other previously published predictive scores. CONCLUSIONS: The HIAT2 score, which combines clinical and imaging variables, performed better than all previous scores in predicting poor outcome after IAT for anterior circulation large artery occlusions.


Assuntos
Isquemia Encefálica/terapia , Acidente Vascular Cerebral/terapia , Terapia Trombolítica/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/tratamento farmacológico , Feminino , Fibrinolíticos/uso terapêutico , Humanos , Injeções Intra-Arteriais , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Radiografia , Reperfusão , Estudos Retrospectivos , Índice de Gravidade de Doença , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/tratamento farmacológico , Ativador de Plasminogênio Tecidual/uso terapêutico , Resultado do Tratamento
17.
Mult Scler ; 19(11): 1499-507, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23828872

RESUMO

BACKGROUND: Chronic cerebrospinal venous insufficiency (CCSVI) was implicated in the pathophysiology of multiple sclerosis (MS). OBJECTIVE: We evaluated neurosonography (NS), magnetic resonance venography (MRV), and transluminal venography (TLV) in subsets of MS patients drawn from a single-center, prospective, case-control study of 206 MS and 70 non-MS volunteers. METHODS: As previously reported, findings on high-resolution B-mode NS imaging with color and spectral Doppler of the extracranial and intracranial venous drainage consistent with CCSVI were similar among MS and non-MS volunteers (3.88% vs 7.14%; p = 0.266). Ninety-nine MS participants consented to intravascular contrast-enhanced 3D MRV to assess their major systemic and intracranial venous circulation, and 40 advanced to TLV that included pressure measurements of the superior vena cava, internal jugular, brachiocephalic, and azygous veins. RESULTS: NS findings and MRV patterns were discrepant for 26/98 evaluable subjects, including four with abnormal findings on NS that had normal venous anatomy by MRV. In no instance were TLV pressure gradients indicative of clinically significant functional stenosis encountered. The three imaging approaches provided generally consistent data with discrepancies referable to inherent technique properties. CONCLUSIONS: Our findings lend no support for altered venous outflow dynamics as common among MS patients, nor do they likely contribute to the disease process.


Assuntos
Encéfalo/irrigação sanguínea , Imagem Multimodal , Esclerose Múltipla/patologia , Medula Espinal/irrigação sanguínea , Insuficiência Venosa/epidemiologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal/métodos , Esclerose Múltipla/complicações , Esclerose Múltipla/etiologia , Flebografia/métodos , Ultrassonografia Doppler/métodos , Insuficiência Venosa/complicações , Insuficiência Venosa/diagnóstico
18.
JAMA Neurol ; 80(11): 1182-1190, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37721738

RESUMO

Importance: The benefit of endovascular stroke therapy (EVT) in large vessel occlusion (LVO) ischemic stroke is highly time dependent. Process improvements to accelerate in-hospital workflows are critical. Objective: To determine whether automated computed tomography (CT) angiogram interpretation coupled with secure group messaging can improve in-hospital EVT workflows. Design, Setting, and Participants: This cluster randomized stepped-wedge clinical trial took place from January 1, 2021, through February 27, 2022, at 4 comprehensive stroke centers (CSCs) in the greater Houston, Texas, area. All 443 participants with LVO stroke who presented through the emergency department were treated with EVT at the 4 CSCs. Exclusion criteria included patients presenting as transfers from an outside hospital (n = 158), in-hospital stroke (n = 39), and patients treated with EVT through randomization in a large core clinical trial (n = 3). Intervention: Artificial intelligence (AI)-enabled automated LVO detection from CT angiogram coupled with secure messaging was activated at the 4 CSCs in a random-stepped fashion. Once activated, clinicians and radiologists received real-time alerts to their mobile phones notifying them of possible LVO within minutes of CT imaging completion. Main Outcomes and Measures: Primary outcome was the effect of AI-enabled LVO detection on door-to-groin (DTG) time and was measured using a mixed-effects linear regression model, which included a random effect for cluster (CSC) and a fixed effect for exposure status (pre-AI vs post-AI). Secondary outcomes included time from hospital arrival to intravenous tissue plasminogen activator (IV tPA) bolus in eligible patients, time from initiation of CT scan to start of EVT, and hospital length of stay. In exploratory analysis, the study team evaluated the impact of AI implementation on 90-day modified Rankin Scale disability outcomes. Results: Among 243 patients who met inclusion criteria, 140 were treated during the unexposed period and 103 during the exposed period. Median age for the complete cohort was 70 (IQR, 58-79) years and 122 were female (50%). Median National Institutes of Health Stroke Scale score at presentation was 17 (IQR, 11-22) and the median DTG preexposure was 100 (IQR, 81-116) minutes. In mixed-effects linear regression, implementation of the AI algorithm was associated with a reduction in DTG time by 11.2 minutes (95% CI, -18.22 to -4.2). Time from CT scan initiation to EVT start fell by 9.8 minutes (95% CI, -16.9 to -2.6). There were no differences in IV tPA treatment times nor hospital length of stay. In multivariable logistic regression adjusted for age, National Institutes of Health Stroke scale score, and the Alberta Stroke Program Early CT Score, there was no difference in likelihood of functional independence (modified Rankin Scale score, 0-2; odds ratio, 1.3; 95% CI, 0.42-4.0). Conclusions and Relevance: Automated LVO detection coupled with secure mobile phone application-based communication improved in-hospital acute ischemic stroke workflows. Software implementation was associated with clinically meaningful reductions in EVT treatment times. Trial Registration: ClinicalTrials.gov Identifier: NCT05838456.


Assuntos
Arteriopatias Oclusivas , Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Masculino , Ativador de Plasminogênio Tecidual/uso terapêutico , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/cirurgia , Inteligência Artificial , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/cirurgia , Procedimentos Endovasculares/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/cirurgia , Trombectomia/métodos , Arteriopatias Oclusivas/tratamento farmacológico , Software , Resultado do Tratamento
20.
Stroke ; 43(2): 591-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22223237

RESUMO

BACKGROUND AND PURPOSE: Current ischemic stroke reperfusion therapy consists of intravenous thrombolysis given in eligible patients after review of a noncontrast CT scan and a time-based window of opportunity. Rapid clot lysis has a strong association with clinical improvement but remains incomplete in many patients. This review appraises novel adjunctive or alternative approaches to current reperfusion strategies being tested in all trial phases. Summary of Review- Alternative approaches to current reperfusion therapy can be separated into 4 main categories: (1) combinatory approaches with other drugs or devices; (2) novel systemic thrombolytic agents; (3) endovascular medical or mechanical reperfusion treatments; and (4) noninvasive or minimally invasive methods to augment cerebral blood flow and alleviate intracranial blood flow steal. CONCLUSIONS: Reperfusion treatments must be provided as fast as possible in patients most likely to benefit. Patients who fail to rapidly reperfuse may benefit from other strategies that maintain collateral flow or protect tissue at risk.


Assuntos
Fibrinolíticos/uso terapêutico , Traumatismo por Reperfusão/tratamento farmacológico , Terapia Trombolítica , Aspirina/uso terapêutico , Terapia por Estimulação Elétrica , Procedimentos Endovasculares , Fibrinogênio/antagonistas & inibidores , Heparina de Baixo Peso Molecular/uso terapêutico , Humanos , Inibidores da Agregação Plaquetária/uso terapêutico , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/antagonistas & inibidores , Traumatismo por Reperfusão/etiologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/tratamento farmacológico , Trombina/antagonistas & inibidores , Tomografia Computadorizada por Raios X , Terapia por Ultrassom
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