Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 51
Filtrar
1.
Neurosci Lett ; 630: 254-258, 2016 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-27345389

RESUMO

GOAL: While transcranial laser therapy (TLT) has been shown to improve clinical outcome in a preclinical model of ischemic stroke, optimal timing and dosing has yet to be tested adequately. The purpose of this study was to assess clinical stroke outcome in the Rabbit Small Clot Embolic Model (RSCEM) with dose escalating TLT. METHODS: We utilized the rabbit small clot embolic stroke model (RSCEM) using dose-escalating regimens. Behavioral analysis was conducted at 24h post-embolization, allowing for the determination of the effective stroke dose (ES50) or clot amount (mg) that produces neurological deficits in 50% of a group of rabbits. Using the RSCEM, a treatment is considered beneficial if it significantly increases the ES50 compared with the control group. FINDINGS: A significant behavioral benefit was seen at triple TLT of 111mW treatment of 2min at 2h post-embolization (6.47±1.06, n=17; p=0.03), compared with the previously used regimen (3.09±0.51, n=15). CONCLUSION: TLT results in significant behavioral improvement when administered 2h post-embolization. Studies are warranted to evaluate this therapy in combination with thrombolysis.


Assuntos
Isquemia Encefálica/terapia , Modelos Animais de Doenças , Embolização Terapêutica/métodos , Terapia a Laser/métodos , Fototerapia/métodos , Acidente Vascular Cerebral/terapia , Animais , Comportamento Animal , Córtex Cerebral/patologia , Embolia Intracraniana/terapia , Coelhos , Resultado do Tratamento
2.
Stroke ; 45(10): 2974-82, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25147328

RESUMO

BACKGROUND AND PURPOSE: Higher low-density lipoprotein cholesterol is associated with more rapid chronic kidney disease progression; reduction in cholesterol with statins, in conjunction with statins' pleiotropic effects, such as decreasing inflammation, may be renoprotective. The Stroke Prevention by Aggressive Reduction in Cholesterol Levels (SPARCL) trial assessed the effect of statin treatment on the risk of nonfatal and fatal stroke in subjects with a noncardioembolic stroke or transient ischemic attack, no known coronary heart disease, and low-density lipoprotein cholesterol between 2.6 and 4.9 mmol/L (100-190 mg/dL). METHODS: We explored the effect of randomization to atorvastatin 80 mg/d or placebo on the change in estimated glomerular filtration rate (eGFR; using the 4-component Modification of Diet in Renal Disease Study equation) in SPARCL subjects (n=4731) with (eGFR, <60 mL/min per 1.73 m2; n=3119) and without (eGFR, ≥60 mL/min per 1.73 m2; n=1600) chronic kidney disease overall and by glycemic status at baseline. RESULTS: Mean baseline eGFR was similar between treatment groups (65.5±0.26 versus 65.6±0.26 mL/min per 1.73 m2 atorvastatin versus placebo; 33% versus 34% had chronic kidney disease, respectively; P=0.55). After 60 months, eGFR increased 3.46±0.33 mL/min per 1.73 m2 in those randomized to atorvastatin versus 1.42±0.34 mL/min per 1.73 m2 in those randomized to placebo (P<0.001) independent of baseline renal function. In the subgroup with diabetes mellitus at randomization, eGFR increased 1.12±0.92 mL/min per 1.73 m2 in the atorvastatin group and decreased 1.69±0.92 mL/min per 1.73 m2 in placebo group during a period of 60 months (P=0.016). CONCLUSIONS: This post hoc analysis suggests that atorvastatin treatment may improve renal function in patients with prior stroke or transient ischemic attack with and without chronic kidney disease, and that atorvastatin treatment may prevent eGFR decline in patients with stroke and diabetes mellitus. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT00147602.


Assuntos
Taxa de Filtração Glomerular/efeitos dos fármacos , Ácidos Heptanoicos/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Ataque Isquêmico Transitório/tratamento farmacológico , Pirróis/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Idoso , Atorvastatina , Método Duplo-Cego , Feminino , Humanos , Rim/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade
3.
Biol Sex Differ ; 5: 9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25061508

RESUMO

BACKGROUND: Biologic sex can influence response to pharmacologic therapy. The purpose of this proof-of-concept study was to evaluate the medicating effects of estrogen in the efficacy of acute antiplatelet loading therapy on stroke outcome in the rabbit small clot embolic model. METHODS: Female and male (20/group) New Zealand White rabbits were embolized to produce embolic stroke by injecting small blood clots into the middle cerebral artery via an internal carotid artery catheter. Two hours after embolization, rabbits were treated with standard dose antiplatelet loading (aspirin 10 mg/kg plus clopidogrel 10 mg/kg). Primary outcome measures were platelet inhibition, behavioral outcome P 50 (the weight of microclots (mg) that produces neurologic dysfunction in 50% of a group of animals), and effect of endogenous estrogen on outcome. RESULTS: For the first time in a non-rodent model of stroke, it was found that higher endogenous estrogen levels resulted in significantly better behavioral outcome in female subjects (r s -0.70, p < 0.011). Platelet inhibition in response to collagen, arachidonic acid, and adenosine diphosphate (ADP) was not significantly different in females with higher vs. lower estrogen levels. CONCLUSIONS: Behavioral outcomes are improved with females with higher endogenous estrogen levels treated with standard dose antiplatelet loading. This is the first non-rodent study to demonstrate that higher endogenous estrogen levels in female rabbits appear to be neuroprotective in ischemic stroke. This research supports the further study of the effect of endogenous estrogen levels on outcome with standard dose antiplatelet loading in stroke patients not eligible for revascularization therapies.

4.
Neurosci Lett ; 553: 99-103, 2013 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-23933199

RESUMO

Transcranial near-infrared laser therapy (TLT) improves stroke outcome in animal models. Adequate laser doses are necessary to exert therapeutic effects. However, applying higher laser energy may cause cortical tissue heating and exacerbate stroke injury. The objective of this study is to examine the thermal effect and safety of transcranial near-infrared laser therapy. Diode laser with a wavelength of 808 nm was used to deliver different power densities to the brain cortex of rabbits. Cortical temperature was monitored and measured using a thermal probe during the 2 min transcranial laser irradiation. Neuro-pathological changes were examined with histological staining 24 h after laser treatment. Transcranial laser irradiation for 2 min at cortical power densities of 22.2 and 55.6 mW/cm(2) with continuous wave (CW) did not increase cortical temperature in rabbits. With the same treatment regime, cortical power density at 111.1 mW/cm(2) increased brain temperature gradually by 0.5 °C over the 2 min exposure and returned to baseline values within 1-2 min post-irradiation. Separately, histological staining was evaluated after triple laser exposure of 22.2 mW/cm(2) CW and 111.1 mW/cm(2) pulse wave (PW) and showed normal neural cell morphology. The present study demonstrated that the TLT powers currently utilized in animal stroke studies do not cause cortical tissue heating and histopathological damage.


Assuntos
Temperatura Corporal , Córtex Cerebral/efeitos da radiação , Lasers Semicondutores/efeitos adversos , Animais , Córtex Cerebral/patologia , Masculino , Coelhos
5.
Stroke ; 44(11): 3246-8, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23982714

RESUMO

BACKGROUND AND PURPOSE: No approved acute therapy exists for thousands of patients with ischemic stroke who present ineligible for thrombolytics. The purpose of this proof-of-concept study was to evaluate the efficacy of acute antiplatelet loading on stroke outcome in the rabbit small clot embolic model. METHODS: Sixty male New Zealand white rabbits were embolized via small clots into the middle cerebral artery. Two hours later, animals were treated with (1) aspirin (5 mg/kg; n=20); (2) usual dual antiplatelet loading (aspirin 10 mg/kg+clopidogrel 10 mg/kg; n=20); or (3) high-dose dual antiplatelet loading (aspirin 10 mg/kg+clopidogrel 30 mg/kg; n=20). The coprimary outcomes were as follows: (1) platelet inhibition and (2) behavioral outcome as measured by the P50 (milligrams of clot that leads to neurological dysfunction in 50% of animals in a group). RESULTS: There was a significant difference in 3-hour arachidonic acid and ADP (P<0.011); 6-hour collagen and ADP (P<0.01, P<0.01); and 24-hour collagen, arachidonic acid, and ADP (P=0.02, P<0.01, P<0.01) platelet inhibition. The behavioral outcome was significantly better in the usual dual antiplatelet loading versus aspirin group (P=0.02). CONCLUSIONS: This study suggests that usual dual antiplatelet loading is clinically beneficial in a validated model of acute stroke. Study of usual dual antiplatelet loading in acute stroke is warranted to provide treatment to stroke victims ineligible for current therapies.


Assuntos
Plaquetas/efeitos dos fármacos , Isquemia Encefálica/tratamento farmacológico , Inibidores da Agregação Plaquetária/farmacologia , Difosfato de Adenosina/sangue , Animais , Ácido Araquidônico/sangue , Aspirina/farmacologia , Colágeno/sangue , Modelos Animais de Doenças , Embolização Terapêutica , Fibrinolíticos/farmacologia , Masculino , Coelhos , Distribuição Aleatória , Resultado do Tratamento
6.
Lasers Med Sci ; 28(4): 1085-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22945539

RESUMO

Transcranial near-infrared laser therapy (TLT) improves behavioral outcome in animal stroke models when applied as single treatment within the 24 h of the stroke onset. It is unknown if the multiple TLT treatments have an added beneficial effect. We aim to determine whether multiple irradiations with TLT would have further improvement in behavioral outcomes in the rabbit small clot embolic stroke model (RSCEM). Using the RSCEM, two and three TLT treatments (7.5-20 mW/cm(2)) were compared against single laser treatment alone (7.5-10.8 mW/cm(2)). Two sham irradiation groups were added for the control curves. The double treatment group received TLT at 3 and 5 h and the triple treatment group at 2, 3, and 4 h after embolization. Behavioral analysis was conducted 24 h after embolization using a dichotomized behavioral score. The determination of the effective clot amount (milligrams) that produces neurological deficits in 50 % of the rabbits (P 50) was used to compare TLT treatments with the sham. The P 50 for double treatment was 5.47 ± 0.90, with n = 39; the corresponding P 50 value for a single treatment was 3.87 ± 0.73, with n = 38; and the corresponding control curve was 3.25 ± 0.4, n = 32. The P 50 for triple treatment was 5.91 ± 0.49, with n = 23; the corresponding P 50 value for a single treatment was 3.09 ± 0.59, with n = 15, and the corresponding control curve was 1.71 ± 0.26, with n = 17. The triple treatment had 91 % improvement when compared with the single treatment and 245 % improvement when compared with the sham. The present study suggests that the additional TLT treatments provide further behavioral improvement when given during the acute ischemic stroke phase.


Assuntos
Comportamento Animal/efeitos da radiação , Terapia com Luz de Baixa Intensidade/métodos , Acidente Vascular Cerebral/psicologia , Acidente Vascular Cerebral/radioterapia , Animais , Modelos Animais de Doenças , Raios Infravermelhos/uso terapêutico , Embolia Intracraniana/complicações , Masculino , Coelhos , Acidente Vascular Cerebral/etiologia , Fatores de Tempo
7.
Int J Stroke ; 8(5): 315-20, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22299818

RESUMO

BACKGROUND: NeuroThera Effectiveness and Safety Trials (NEST) 1 and 2 have demonstrated safety of transcranial laser therapy (TLT) for human treatment in acute ischemic stroke. NEST 1 study suggested efficacy of TLT but the following NEST 2, despite strong signals, missed reaching significance on its primary efficacy endpoint. In order to assess efficacy in a larger cohort, a pooled analysis was therefore performed. METHODS: The two studies were first compared for heterogeneity, and then a pooled analysis was performed to assess overall safety and efficacy, and examined particular subgroups. The primary endpoint for the pooled analysis was dichotomized modified Rankin scale (mRS) 0-2 at 90 days. RESULTS: Efficacy analysis for the intention-to-treat population was based on a total of 778 patients. Baseline characteristics and prognostic factors were balanced between the two groups. The TLT group (n = 410) success rate measured by the dichotomized 90-day mRS was significantly higher compared with the sham group (n = 368) (P = 0·003, OR: 1·67, 95% CI: 1·19-2·35). The distribution of scores on the 90-day mRS was significantly different in TLT compared with sham (P = 0·0005 Cochran-Mantel-Haenszel). Subgroup analysis identified moderate strokes as a predictor of better treatment response. CONCLUSIONS: This pooled analysis support the likelihood that transcranial laser therapy is effective for the treatment of acute ischemic stroke when initiated within 24 h of stroke onset. If ultimately confirmed, transcranial laser therapy will change management and improve outcomes of far more patients with acute ischemic stroke.


Assuntos
Isquemia Encefálica/complicações , Terapia a Laser/métodos , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Cooperação Internacional , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Índice de Gravidade de Doença
8.
Womens Health (Lond) ; 7(4): 465-74, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21790339

RESUMO

Sex differences exist in the occurrence, treatment and outcome of ischemic stroke. Compared with men, women have more stroke events and are less likely to fully recover from a stroke. Given the rapidly aging population, stroke incidence and mortality among women are projected to substantially rise by 2050. This has important public health consequences. Mitigating the burden of stroke among women will require a fundamental understanding of sex differences and sex-specific issues including cerebrovascular disease pathophysiology, treatment and outcome. An aspect of stroke treatment receiving increasing but insufficient attention involves possible interactions between estrogen levels, antiplatelet drugs and stroke outcome. Emerging evidence suggests that antiplatelet therapy may provide primary stroke protection but not primary myocardial infarction prevention in women, while the opposite may be true among men. Understanding sex-specific issues related to women who experience stroke is critical to clinicians who treat women with antiplatelet medications as part of a secondary stroke prevention regimen; however, the ideal antiplatelet medication, and dose, in women requires further research. In this article we present a conceptual framework for sex differences in antiplatelet treatment response in ischemic stroke, thrombus formation and the mediating role of estrogen, sex differences in antiplatelet treatment response in clinical trials, and sex differences in antiplatelet treatment use in ischemic stroke.


Assuntos
Isquemia Encefálica/prevenção & controle , Transtornos Cerebrovasculares/prevenção & controle , Infarto do Miocárdio/prevenção & controle , Inibidores da Agregação Plaquetária/uso terapêutico , Saúde da Mulher , Anticoagulantes/uso terapêutico , Isquemia Encefálica/tratamento farmacológico , Transtornos Cerebrovasculares/tratamento farmacológico , Medicina Baseada em Evidências , Feminino , Humanos , Masculino , Infarto do Miocárdio/tratamento farmacológico , Fatores de Risco , Distribuição por Sexo , Fatores Sexuais , Estados Unidos
9.
Arch Neurol ; 68(10): 1245-51, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21670382

RESUMO

OBJECTIVE: To perform a secondary analysis of the Stroke Prevention by Aggressive Reduction in Cholesterol Levels (SPARCL) trial, which tested the effect of treatment with atorvastatin in reducing stroke in subjects with a recent stroke or transient ischemic attack, to explore the effects of treatment in subjects with type 2 diabetes mellitus or metabolic syndrome (MetS). METHODS: The 4731 subjects enrolled in the SPARCL trial were classified as having type 2 diabetes mellitus at enrollment (n = 794), MetS retrospectively (n = 642), or neither diabetes nor MetS (n = 3295, the reference group) based on data collected at baseline. Cox regression models were used to determine whether the effect of treatment on the primary end point (combined risk of nonfatal and fatal stroke) and secondary end points (major coronary events, major cardiovascular events, any coronary heart disease event, and any revascularization procedure) varied based on the presence of type 2 diabetes mellitus or MetS. RESULTS: Subjects with type 2 diabetes mellitus had increased risks of stroke (hazard ratio [HR] = 1.62; 95% confidence interval [CI], 1.33-1.98; P < .001), major cardiovascular events (HR = 1.66; 95% CI, 1.39-1.97; P < .001), and revascularization procedures (HR = 2.39; 95% CI, 1.78-3.19; P < .001) compared with the reference group. Subjects with MetS were not at increased risk for stroke (P = .78) or major cardiovascular events (P = .38) but more frequently had revascularization procedures (HR = 1.78; 95% CI, 1.26-2.5; P = .001). There were no treatment × subgroup interactions for the SPARCL primary end point (P = .47). CONCLUSIONS: The SPARCL subjects with type 2 diabetes were at higher risk for recurrent stroke and cardiovascular events. This exploratory analysis found no difference in the effect of statin treatment in reducing these events in subjects with or without type 2 diabetes or MetS. Trial Registration clinicaltrials.gov Identifier: NCT00147602.


Assuntos
Colesterol/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Ácidos Heptanoicos/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Ataque Isquêmico Transitório/complicações , Síndrome Metabólica/complicações , Pirróis/uso terapêutico , Acidente Vascular Cerebral/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Atorvastatina , Fenômenos Fisiológicos Cardiovasculares/efeitos dos fármacos , Intervalos de Confiança , Diabetes Mellitus Tipo 2/complicações , Feminino , Humanos , Ataque Isquêmico Transitório/tratamento farmacológico , Ataque Isquêmico Transitório/epidemiologia , Lipoproteínas HDL/sangue , Lipoproteínas LDL/sangue , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Triglicerídeos/sangue , Adulto Jovem
10.
Curr Treat Options Cardiovasc Med ; 13(3): 233-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21424751

RESUMO

OPINION STATEMENT: Intravenous alteplase or tissue plasminogen activator (tPA) has been the standard of care with proven efficacy for acute ischemic stroke for over a decade. Despite this, only a small fraction of potentially eligible stroke patients receive this medication. There seems to be a fear among practitioners of legal repercussions as a result of an increased risk of intracerebral hemorrhage due to tPA. This review of legal cases involving tPA will show that instead, physicians are often found liable as a result of not treating with tPA.

11.
Arch Neurol ; 67(10): 1210-8, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20937948

RESUMO

OBJECTIVES: Our primary objective was to determine the proportion of the population able to achieve acute cerebrovascular care in emergency stroke systems (ACCESS) in the United States. In addition, we examined how policy changes, including allowing ground ambulances to cross state lines and allowing air ambulances to transport patients from the prehospital setting to primary stroke centers (PSCs), would affect population access to stroke care. DESIGN: Data were obtained via the US Census Bureau, The Joint Commission, and the Atlas and Database of Air Medical Services. Driving distances, ambulance driving speeds, and prehospital times were estimated using validated models and adjusted for population density. Access was determined by summing the population that could reach a PSC within the specified time intervals. SETTING/ PARTICIPANTS: US population. MAIN OUTCOME MEASURES: Thirty-, 45-, and 60-minute access by ground and air ambulance to PSCs. RESULTS: Fewer than 1 in 4 Americans (22.3%) have access to a PSC within 30 minutes, less than half (43.2%) have access within 45 minutes, and just over half (55.4%) have access within 60 minutes. The use of air ambulances to deliver patients to PSCs would increase access from 22.3% to 26.0% for 30 minutes, 43.2% to 65.5% for 45 minutes, and from 55.4% to 79.3% for 60 minutes. The combination of prehospital regionalization and air ambulance transport of patients with acute stroke would reduce the 135.7 million Americans without 60-minute access to a PSC by half, to 62.9 million. CONCLUSIONS: About half of the US population has timely access to a PSC. The use of air ambulances to triage patients with ischemic stroke to a PSC would increase the percentage of the US population with prompt access to stroke care. These data have implications for the ongoing design of the US stroke system.


Assuntos
Serviço Hospitalar de Emergência/estatística & dados numéricos , Acessibilidade aos Serviços de Saúde , Acidente Vascular Cerebral/terapia , Fatores Etários , Planejamento em Saúde Comunitária/estatística & dados numéricos , Sistemas de Informação Geográfica , Humanos , Acidente Vascular Cerebral/epidemiologia , Fatores de Tempo , Transporte de Pacientes , Estados Unidos/epidemiologia
12.
Vasc Health Risk Manag ; 6: 229-36, 2010 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-20407630

RESUMO

Statin therapy in patients with cardiovascular disease is associated with reduced incidence of stroke. The Stroke Prevention by Aggressive Reduction of Cholesterol Levels (SPARCL) trial showed daily treatment with 80 mg of atorvastatin in patients with a recent stroke or transient ischemic attack (TIA) reduced the incidence of fatal or nonfatal stroke by 16%. Several post hoc analyses of different subgroups followed the SPARCL study. They have not revealed any significant differences when patients were sorted by age, sex, presence of carotid disease or type of stroke, with the exception of intracranial hemorrhage as the entry event. Lower low-density lipoprotein cholesterol levels in addition to possible neuroprotective mechanisms due to atorvastatin treatment correlate with improved risk reduction. Although not predefined subgroups and subject to an insufficient power, these post hoc studies have generated new clinical questions. However, clinicians should avoid denying therapy based on such subgroup analysis. At this point, the best evidence powerfully demonstrates stroke and TIA patients should be prescribed high dose statin therapy for secondary stroke prevention.


Assuntos
Ácidos Heptanoicos/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Ataque Isquêmico Transitório/prevenção & controle , Pirróis/uso terapêutico , Acidente Vascular Cerebral/prevenção & controle , Fatores Etários , Idoso , Atorvastatina , Doenças das Artérias Carótidas/complicações , LDL-Colesterol/sangue , Feminino , Humanos , Hemorragias Intracranianas/induzido quimicamente , Ataque Isquêmico Transitório/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores Sexuais , Acidente Vascular Cerebral/tratamento farmacológico , Resultado do Tratamento
13.
Curr Cardiol Rep ; 12(1): 29-33, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20425181

RESUMO

Intravenous tissue plasminogen activator is the only proven therapy for acute ischemic stroke. Not enough patients are eligible for treatment and additional new therapies are needed. Recently, laser technology has been applied to acute ischemic stroke. This noninvasive technique uses near-infrared wavelengths applied to the scalp within 24 h of symptom onset. The mechanism is incompletely understood but may involve increased mitochondrial adenosine triphosphate production. Animal models demonstrated safety and efficacy warranting randomized controlled trials in humans. NEST-1 (phase 2) and NEST-2 (phase 3) confirmed the safety of transcranial laser therapy, although efficacy was not found in NEST-2. Pooled analysis of NEST-1 and NEST-2 revealed a significantly improved success rate in patients treated with laser therapy. Further phase 3 testing is planned and may create a new paradigm for the treatment of acute ischemic stroke.


Assuntos
Isquemia Encefálica/cirurgia , Terapia a Laser/métodos , Acidente Vascular Cerebral/cirurgia , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Intervalos de Confiança , Método Duplo-Cego , Indicadores Básicos de Saúde , Humanos , Terapia a Laser/efeitos adversos , Modelos Logísticos , Pessoa de Meia-Idade , Modelos Animais , Estudos Multicêntricos como Assunto , Análise Multivariada , Razão de Chances , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Ativador de Plasminogênio Tecidual
14.
Stroke ; 41(3): 426-30, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20110538

RESUMO

BACKGROUND AND PURPOSE: Noncoronary forms of atherosclerosis (including transient ischemic attacks or stroke of carotid origin or >50% stenosis of the carotid artery) are associated with a 10-year vascular risk of >20% and are considered as a coronary heart disease (CHD) -risk equivalent from the standpoint of lipid management. The Stroke Prevention by Aggressive Reduction in Cholesterol Levels (SPARCL) trial included patients with stroke or transient ischemic attack and no known CHD regardless of the presence of carotid atherosclerosis. We evaluated the risk of developing clinically recognized CHD in SPARCL patients. METHODS: A total of 4731 patients (mean age, 63 years) was randomized to 80 mg/day atorvastatin placebo. The rates of major coronary event, any CHD event, and any revascularization procedure were evaluated. RESULTS: After 4.9 years of follow-up, the risks of a major coronary event and of any CHD end point in the placebo group were 5.1% and 8.6%, respectively. The rate of outcome of stroke decreased over time, whereas the major coronary event rate was stable. Relative to those having a large vessel-related stroke at baseline, those having a transient ischemic attack, hemorrhagic stroke, small vessel stroke, or a stroke of unknown cause had similar absolute rates for a first major coronary event and for any CHD event; transient ischemic attack, small vessel, and unknown cause groups had lower absolute revascularization procedure rates. Major coronary event, any CHD event, and any revascularization procedure rates were similarly reduced in all baseline stroke subtypes in the atorvastatin arm compared with placebo with no heterogeneity between groups. CONCLUSIONS: CHD risk can be substantially reduced by atorvastatin therapy in patients with recent stroke or transient ischemic attack regardless of stroke subtype.


Assuntos
Colesterol/sangue , Doença das Coronárias/sangue , Ataque Isquêmico Transitório/sangue , Ataque Isquêmico Transitório/prevenção & controle , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/prevenção & controle , Atorvastatina , Doença das Coronárias/tratamento farmacológico , Doença das Coronárias/etiologia , Método Duplo-Cego , Feminino , Seguimentos , Ácidos Heptanoicos/uso terapêutico , Humanos , Ataque Isquêmico Transitório/complicações , Masculino , Pirróis/uso terapêutico , Acidente Vascular Cerebral/complicações
15.
Ann Neurol ; 66(1): 6-10, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19681102

RESUMO

Tissue plasminogen activator (tPA) for acute ischemic stroke was approved by the U.S. Food and Drug Administration (FDA) in 1996. Since then it has been severely underutilized. At the time when most practitioners were first being exposed to the literature concerning tPA, there were many concerns about safety and the restrictions on use were quite onerous. Since then a good deal of further work has been done to loosen the restrictions and allay concerns about the risks. The true risk to benefit ratio is far better than is generally realized. Now it is mostly economic problems related to the costs of constantly supplying emergency care that is limiting access. Furthermore, in the current litigious environment, failure to treat is likely to be a more hazardous course of action than legal exposure due to poor outcomes. It must be emphasized that the drug is quite safe and highly effective, and current utilization rates are unacceptably low. Ann Neurol 2009;66:6-10.


Assuntos
Acidente Vascular Cerebral/tratamento farmacológico , Ativador de Plasminogênio Tecidual/uso terapêutico , United States Food and Drug Administration/legislação & jurisprudência , Aprovação de Drogas/história , História do Século XX , História do Século XXI , Humanos , Ativador de Plasminogênio Tecidual/economia , Estados Unidos , United States Food and Drug Administration/normas
16.
Stroke ; 40(7): 2486-92, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19461031

RESUMO

BACKGROUND AND PURPOSE: The relative contributions of on-treatment low- and high-density lipoprotein cholesterol (LDL-C, HDL-C), triglycerides, and blood pressure (BP) control on the risk of recurrent stroke or major cardiovascular events in patients with stroke is not well defined. METHODS: We randomized 4731 patients with recent stroke or transient ischemic attack and no known coronary heart disease to atorvastatin 80 mg per day or placebo. RESULTS: After 4.9 years, at each level of LDL-C reduction, subjects with HDL-C value above the median or systolic BP below the median had greater reductions in stroke and major cardiovascular events and those with a reduction in triglycerides above the median or diastolic BP below the median showed similar trends. There were no statistical interactions between on-treatment LDL-C, HDL-C, triglycerides, and BP values. In a further exploratory analysis, optimal control was defined as LDL-C <70 mg per deciliter, HDL-C >50 mg per deciliter, triglycerides <150 mg per deciliter, and SBP/DBP <120/80 mm Hg. The risk of stroke decreased with as the level of control increased (hazard ratio [95% confidence interval] 0.98 [0.76 to 1.27], 0.78 [0.61 to 0.99], 0.62 [0.46 to 0.84], and 0.35 [0.13 to 0.96]) for those achieving optimal control of 1, 2, 3, or 4 factors as compared to none, respectively. Results were similar for major cardiovascular events. CONCLUSIONS: We found a cumulative effect of achieving optimal levels of LDL-C, HDL-C, triglycerides, and BP on the risk of recurrent stroke and major cardiovascular events. The protective effect of having a higher HDL-C was maintained at low levels of LDL-C.


Assuntos
Anticolesterolemiantes/uso terapêutico , Pressão Sanguínea/fisiologia , Colesterol/sangue , Ácidos Heptanoicos/uso terapêutico , Hipercolesterolemia/tratamento farmacológico , Pirróis/uso terapêutico , Acidente Vascular Cerebral/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Atorvastatina , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Feminino , Humanos , Hipercolesterolemia/sangue , Hipercolesterolemia/fisiopatologia , Ataque Isquêmico Transitório/epidemiologia , Ataque Isquêmico Transitório/patologia , Ataque Isquêmico Transitório/prevenção & controle , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Prevenção Secundária , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/fisiopatologia , Resultado do Tratamento , Triglicerídeos/sangue , Adulto Jovem
17.
Stroke ; 40(4): 1405-9, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19228842

RESUMO

BACKGROUND AND PURPOSE: The SPARCL trial showed that atorvastatin 80 mg/d reduces the risk of stroke and other cardiovascular events in patients with recent stroke or transient ischemic attack (TIA). We tested the hypothesis that the benefit of treatment varies according to index event stroke subtype. METHODS: Subjects with stroke or TIA without known coronary heart disease were randomized to atorvastatin 80 mg/d or placebo. The SPARCL primary end point was fatal or nonfatal stroke. Secondary end points included major cardiovascular events (MCVE; stroke plus major coronary events). Cox regression models testing for an interaction with treatment assignment were used to explore potential differences in efficacy based on stroke subtype. RESULTS: For subjects randomized to atorvastatin versus placebo, a primary end point occurred in 13.1% versus 18.6% of those classified as having large vessel disease (LVD, 15.8% of 4,731 participants), in 13.1% versus 15.5% of those with small vessel disease (SVD, 29.8%), in 11.2% versus 12.7% of those with ischemic stroke of unknown cause (21.5%), in 7.6% versus 8.8% of those with TIA (30.9%), and in 22.2% versus 8.3% of those with hemorrhagic stroke (HS, 2%) at baseline. There was no difference in the efficacy of treatment for either the primary end point (LVD hazard ratio [HR] 0.70, 95% confidence interval [CI] 0.49 to 1.02, TIA HR 0.81, CI 0.57 to 1.17, SVD HR 0.85, CI 0.64 to 1.12, unknown cause HR 0.87, CI 0.61 to 1.24, HS HR 3.24, CI 1.01 to 10.4; P for heterogeneity=0.421), or MCVEs (P for heterogeneity=0.360) based on subtype of the index event. As compared to subjects with LVD strokes, those with SVD had similar MCVE rates (19.2% versus 18.5% over the course of the trial), and similar overall reductions in stroke and MCVEs. CONCLUSIONS: Atorvastatin 80 mg/d is similarly efficacious in preventing strokes and other cardiovascular events, irrespective of baseline ischemic stroke subtype.


Assuntos
Anticolesterolemiantes/administração & dosagem , Isquemia Encefálica/prevenção & controle , Hemorragia Cerebral/prevenção & controle , Ácidos Heptanoicos/administração & dosagem , Hipercolesterolemia/tratamento farmacológico , Pirróis/administração & dosagem , Acidente Vascular Cerebral/prevenção & controle , Atorvastatina , Isquemia Encefálica/epidemiologia , Hemorragia Cerebral/epidemiologia , Feminino , Humanos , Hipercolesterolemia/epidemiologia , Masculino , Pessoa de Meia-Idade , Placebos , Modelos de Riscos Proporcionais , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Resultado do Tratamento
18.
Stroke ; 40(4): 1359-64, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19233936

RESUMO

BACKGROUND AND PURPOSE: We hypothesized that transcranial laser therapy (TLT) can use near-infrared laser technology to treat acute ischemic stroke. The NeuroThera Effectiveness and Safety Trial-2 (NEST-2) tested the safety and efficacy of TLT in acute ischemic stroke. METHODS: This double-blind, randomized study compared TLT treatment to sham control. Patients receiving tissue plasminogen activator and patients with evidence of hemorrhagic infarct were excluded. The primary efficacy end point was a favorable 90-day score of 0 to 2 assessed by the modified Rankin Scale. Other 90-day end points included the overall shift in modified Rankin Scale and assessments of change in the National Institutes of Health Stroke Scale score. RESULTS: We randomized 660 patients: 331 received TLT and 327 received sham; 120 (36.3%) in the TLT group achieved favorable outcome versus 101 (30.9%), in the sham group (P=0.094), odds ratio 1.38 (95% CI, 0.95 to 2.00). Comparable results were seen for the other outcome measures. Although no prespecified test achieved significance, a post hoc analysis of patients with a baseline National Institutes of Health Stroke Scale score of <16 showed a favorable outcome at 90 days on the primary end point (P<0.044). Mortality rates and serious adverse events did not differ between groups with 17.5% and 17.4% mortality, 37.8% and 41.8% serious adverse events for TLT and sham, respectively. CONCLUSIONS: TLT within 24 hours from stroke onset demonstrated safety but did not meet formal statistical significance for efficacy. However, all predefined analyses showed a favorable trend, consistent with the previous clinical trial (NEST-1). Both studies indicate that mortality and adverse event rates were not adversely affected by TLT. A definitive trial with refined baseline National Institutes of Health Stroke Scale exclusion criteria is planned.


Assuntos
Isquemia Encefálica/radioterapia , Terapia com Luz de Baixa Intensidade/efeitos adversos , Terapia com Luz de Baixa Intensidade/métodos , Acidente Vascular Cerebral/radioterapia , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/mortalidade , Feminino , Humanos , Raios Infravermelhos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Acidente Vascular Cerebral/mortalidade , Resultado do Tratamento
19.
Atherosclerosis ; 204(2): 515-20, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18962621

RESUMO

OBJECTIVE: To explore the relative contributions of baseline systolic blood pressure (SBP) and diastolic blood pressure (DBP) and lipoproteins on the risk of recurrent stroke or first major cardiovascular event (MCVE) and their potential impact on the benefit of statin treatment. METHODS AND RESULTS: The SPARCL trial randomized 4731 patients with recent stroke or transient ischemic attack (TIA) and no known coronary heart disease and LDL-C between 100 and 190 mg/dL to either atorvastatin 80 mg/d or placebo. Baseline assessment included SBP, DBP and measurements of low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C), and triglyceride levels. After 4.9 years of follow-up, there were 575 primary end points (fatal and nonfatal stroke), including 491 ischemic strokes, and 740 MCVEs (stroke plus myocardial infarction and vascular death). Cox regression models analysis showed a trend (P>0.05 and P<0.10) for higher SBP but not DBP to be associated with an outcome stroke with only SBP associated with MCVE. Only baseline low HDL-C was associated with an outcome stroke. Baseline HDL-C, triglycerides, and LDL/HDL ratio were each associated with MCVEs. There were no interactions between any of these baseline variables and the effect of treatment on outcome strokes. CONCLUSIONS: In patients with recent stroke or TIA and no coronary heart disease, only lower baseline HDL-C predicted the risk of recurrent stroke with HDL-C, triglycerides, and LDL/HDL ratio associated with MCVE. Atorvastatin treatment was similarly effective regardless of baseline lipoprotein levels.


Assuntos
Pressão Sanguínea , Doenças Cardiovasculares/prevenção & controle , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Ácidos Heptanoicos/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Ataque Isquêmico Transitório/tratamento farmacológico , Pirróis/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Triglicerídeos/sangue , Idoso , Atorvastatina , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/fisiopatologia , Feminino , Humanos , Ataque Isquêmico Transitório/sangue , Ataque Isquêmico Transitório/mortalidade , Ataque Isquêmico Transitório/fisiopatologia , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Medição de Risco , Fatores de Risco , Prevenção Secundária , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/fisiopatologia , Fatores de Tempo , Resultado do Tratamento
20.
Exp Neurol ; 215(1): 95-100, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18851964

RESUMO

Edaravone is a lipophilic drug with multiple mechanisms of action. Because edaravone is a promising drug candidate for the treatment of stroke, we tested the hypothesis that edaravone would be neuroprotective following cerebral ischemia using a rabbit embolic stroke model with a well-defined behavioral endpoint. Using the rabbit small clot embolic stroke model (RSCEM), a drug or drug combination is considered beneficial if it significantly increases the amount of microclots (mg) measured in brain that produce neurologic dysfunction in 50% of a group of animals (P(50)) compared to the control group. Edaravone (100 mg/kg, s.c.), increased the P(50) value to 1.80+/-0.24 mg (p<0.05) when administered 5 min following embolization and increased P(50) values by 195% and 161% (compared to control) when administered 1 and 3 h following embolization, respectively, but was inactive when applied 6 h following embolization, compared to the cumulative control group (P(50)=0.93+/-0.16 mg). To simulate the design of current clinical trials, edaravone was also given following a standard tPA regimen, which by itself increased the P(50) value to 2.72+/-0.28 mg. When tPA was infused 1 h following embolization and edaravone was given 3 h following embolization, the P(50) was 2.68+/-0.56 mg. This study indicates that edaravone may have substantial therapeutic benefit for the treatment of AIS since it had a therapeutic widow of at least 3 h in rabbits. Edaravone can also be administered with a thrombolytic to improve behavior.


Assuntos
Antipirina/análogos & derivados , Comportamento Animal/efeitos dos fármacos , Fibrinolíticos/uso terapêutico , Sequestradores de Radicais Livres/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Ativador de Plasminogênio Tecidual/uso terapêutico , Animais , Antipirina/uso terapêutico , Trombose das Artérias Carótidas/complicações , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Edaravone , Modelos Logísticos , Coelhos , Acidente Vascular Cerebral/etiologia , Fatores de Tempo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...