RESUMO
Post-traumatic growth (PTG) is the experience of positive changes that can follow a traumatic event. The current study examined the factorial as well as the discriminant validity of the German version of the Post-traumatic Growth Inventory (PTGI-G) in stroke patients. A total of 188 adult stroke patients (63.3% male; median age 69â years) completed the PTGI-G and the German version of the Hospital Anxiety and Depression Scale (HADS-D) at the end of their inpatient rehabilitation. Confirmatory factor analyses indicate an acceptable model fit of both the original five-factor solution as well as a second-order factor model of the PTGI-G (CFI > .95; RMSEA < .01). Small and non-significant correlations between the PTGI-G subscales and the depression scale of the HADS-D support the discriminant validity of the PTGI-G. The PTGI-G appears to be a valid tool in the context of stroke research.
Assuntos
Adaptação Psicológica , Autorrelato/normas , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Ansiedade/etiologia , Ansiedade/reabilitação , Depressão/etiologia , Depressão/reabilitação , Análise Fatorial , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Acidente Vascular Cerebral/complicaçõesRESUMO
The controversy as to whether Doppler ultrasonic methods should play a role in clinical decision-making in the prevention of stroke is attributable to reported disagreement between angiographic and ultrasonic results and the lack of internationally accepted ultrasound criteria for describing the degree of stenosis. Foremost among the explanations for both is the broad scatter of peak systolic velocities in the stenosis, the criterion that has so far received most attention. Grading based on a set of main and additional criteria can overcome diagnostic errors. Morphological measurements (B-mode images and color flow imaging) are the main criteria for low and moderate degrees of stenosis. Increased velocities in the stenosis indicate narrowing, but the appearance of collateral flow and decreased poststenotic flow velocity prove a high degree stenosis (≥70%), additionally allowing the estimation of the hemodynamic effect in the category of high-degree stenosis. Additional criteria refer to the effect of a stenosis on prestenotic flow (common carotid artery), the extent of poststenotic flow disturbances, and derived velocity criteria (diastolic peak velocity and the carotid ratio). This multiparametric approach is intended to increase the reliability and the standard of reporting of ultrasonic results for arteriosclerotic disease of the carotid artery.
Assuntos
Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/diagnóstico , Ecocardiografia/métodos , Estenose das Carótidas/fisiopatologia , Ecocardiografia Doppler , Ecocardiografia Doppler em Cores , Hemodinâmica/fisiologia , Humanos , Reprodutibilidade dos TestesRESUMO
OBJECTIVE: To compare the impact of initial corticosteroid treatment on high-resolution MRI and colour-coded duplex sonography (CCDS) findings in patients with GCA (temporal). METHODS: Sensitivity and specificity of CCDS and high-resolution contrast-enhanced MRI studies of 59 patients with suspected GCA were retrospectively analysed. Patients were grouped according to the duration of steroid treatment before imaging: 0-1 day, 2-4 days and >4 days. In 41 patients, imaging results were compared with findings of temporal artery biopsy (TAB). RESULTS: Sixty-one per cent (36/59) of patients were diagnosed with GCA. TAB findings were positive in 59% (24/41). The compared results of TAB sensitivity of CCDS and MRI under steroid treatment of 0-1 day were 92% and 90%, 2-4 days 80% and 78% and >4 days 50% and 80%, respectively. The compared results of the final clinical diagnosis sensitivity of CCDS and MRI under steroid treatment of 0-1 day was 88% and 85%, 2-4 days 50% and 64% and >4 days 50% and 56%, respectively. CONCLUSION: Sensitivity of a first-time CCDS or an MRI for detection of GCA rapidly decreases under corticosteroid treatment. Therefore imaging of patients with suspected GCA should be performed as soon as possible, preferably within the first days of treatment.
Assuntos
Corticosteroides/uso terapêutico , Arterite de Células Gigantes/tratamento farmacológico , Idoso , Feminino , Arterite de Células Gigantes/patologia , Humanos , Angiografia por Ressonância Magnética , Masculino , Estudos Retrospectivos , Sensibilidade e Especificidade , Ultrassonografia Doppler em CoresRESUMO
BACKGROUND: Studies to date have shown an association between the presence of patent foramen ovale and cryptogenic stroke in patients younger than 55 years of age. This association has not been established in patients 55 years of age or older. METHODS: We prospectively examined 503 consecutive patients who had had a stroke, and we compared the 227 patients with cryptogenic stroke and the 276 control patients with stroke of known cause. We examined the prevalences of patent foramen ovale and of patent foramen ovale with concomitant atrial septal aneurysm in all patients, using transesophageal echocardiography. We also compared data for the 131 younger patients (< 55 years of age) and those for the 372 older patients (> or = 55 years of age). RESULTS: The prevalence of patent foramen ovale was significantly greater among patients with cryptogenic stroke than among those with stroke of known cause, for both younger patients (43.9% vs. 14.3%; odds ratio, 4.70; 95% confidence interval [CI], 1.89 to 11.68; P<0.001) and older patients (28.3% vs. 11.9%; odds ratio, 2.92; 95% CI, 1.70 to 5.01; P<0.001). Even stronger was the association between the presence of patent foramen ovale with concomitant atrial septal aneurysm and cryptogenic stroke, as compared with stroke of known cause, among both younger patients (13.4% vs. 2.0%; odds ratio, 7.36; 95% CI, 1.01 to 326.60; P=0.049) and older patients (15.2% vs. 4.4%; odds ratio, 3.88; 95% CI, 1.78 to 8.46; P<0.001). Multivariate analysis adjusted for age, plaque thickness, and presence or absence of coronary artery disease and hypertension showed that the presence of patent foramen ovale was independently associated with cryptogenic stroke in both the younger group (odds ratio, 3.70; 95% CI, 1.42 to 9.65; P=0.008) and the older group (odds ratio, 3.00; 95% CI, 1.73 to 5.23; P<0.001). CONCLUSIONS: There is an association between the presence of patent foramen ovale and cryptogenic stroke in both older patients and younger patients. These data suggest that paradoxical embolism is a cause of stroke in both age groups.
Assuntos
Embolia Paradoxal/complicações , Forame Oval Patente/complicações , Acidente Vascular Cerebral/etiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Forame Oval Patente/epidemiologia , Aneurisma Cardíaco/complicações , Humanos , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Prevalência , Estudos Prospectivos , Fatores de RiscoRESUMO
BACKGROUND: Natalizumab inhibits adherence of leukocytes to the cerebral endothelium. Since leukocytes play a role in regulating vascular tone, natalizumab may also affect cerebral vasoregulation. The aim of this observational study was to investigate whether neurovascular coupling and cerebral autoregulation are altered following routine clinical infusion of natalizumab in patients with relapsing-remitting multiple sclerosis. METHODS: In 18 patients receiving regular infusion of 300 mg natalizumab, neurovascular coupling to visual stimulation and dynamic cerebral autoregulation (phase and gain of 0.1-Hz oscillations) were measured by transcranial Doppler ultrasound (before, and 2 h and 2 days after the infusion). A repeated examination 28 days after infusion served as a control situation. RESULTS: Neurovascular coupling was altered 2 h and 2 days after infusion with an overshooting initial hemodynamic response. After 28 days, neurovascular coupling was similar to values before the infusion. Dynamic cerebral autoregulation, cerebral blood flow velocity and pulsatility index in the middle and posterior cerebral artery were unaltered. CONCLUSION: Natalizumab infusion is associated with a temporarily increased initial hyperemia to functional activation. Such a hyperreactivity suggests an increased bioavailability of nitric oxide during functional activation.
Assuntos
Anticorpos Monoclonais/administração & dosagem , Circulação Cerebrovascular/efeitos dos fármacos , Esclerose Múltipla/fisiopatologia , Adulto , Análise de Variância , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais Humanizados , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Velocidade do Fluxo Sanguíneo/fisiologia , Circulação Cerebrovascular/fisiologia , Feminino , Humanos , Infusões Intravenosas/métodos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/diagnóstico por imagem , Natalizumab , Observação , Estatísticas não Paramétricas , Fatores de Tempo , Ultrassonografia Doppler Transcraniana/métodosRESUMO
BACKGROUND: By mapping the dynamics of brain reorganization, functional magnetic resonance imaging MRI (fMRI) has allowed for significant progress in understanding cerebral plasticity phenomena after a stroke. However, cerebro-vascular diseases can affect blood oxygen level dependent (BOLD) signal. Cerebral autoregulation is a primary function of cerebral hemodynamics, which allows to maintain a relatively constant blood flow despite changes in arterial blood pressure and perfusion pressure. Cerebral autoregulation is reported to become less effective in the early phases post-stroke. This study investigated whether any impairment of cerebral hemodynamics that occurs during the acute and the subacute phases of ischemic stroke is related to changes in BOLD response. We enrolled six aphasic patients affected by acute stroke. All patients underwent a Transcranial Doppler to assess cerebral autoregulation (Mx index) and fMRI to evaluate the amplitude and the peak latency (time to peak-TTP) of BOLD response in the acute (i.e., within four days of stroke occurrence) and the subacute (i.e., between five and twelve days after stroke onset) stroke phases. RESULTS: As patients advanced from the acute to subacute stroke phase, the affected hemisphere presented a BOLD TTP increase (p = 0.04) and a deterioration of cerebral autoregulation (Mx index increase, p = 0.046). A similar but not significant trend was observed also in the unaffected hemisphere. When the two hemispheres were grouped together, BOLD TTP delay was significantly related to worsening cerebral autoregulation (Mx index increase) (Spearman's rho = 0.734; p = 0.01). CONCLUSIONS: The hemodynamic response function subtending BOLD signal may present a delay in peak latency that arises as patients advance from the acute to the subacute stroke phase. This delay is related to the deterioration of cerebral hemodynamics. These findings suggest that remodeling the fMRI hemodynamic response function in the different phases of stroke may optimize the detection of BOLD signal changes.
Assuntos
Córtex Auditivo/fisiopatologia , Circulação Cerebrovascular , Oxigênio/sangue , Acidente Vascular Cerebral/fisiopatologia , Doença Aguda , Afasia/etiologia , Velocidade do Fluxo Sanguíneo , Hemodinâmica , Homeostase , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Ultrassonografia Doppler TranscranianaRESUMO
BACKGROUND: The Ischemic Stroke System is a novel device designed to deliver stimulation to the sphenopalatine ganglion(SPG).The SPG sends parasympathetic innervations to the anterior cerebral circulation. In rat stroke models, SPG stimulation results in increased cerebral blood flow, reduced infarct volume, protects the blood brain barrier, and improved neurological outcome. We present here the results of a prospective, multinational, single-arm, feasibility study designed to assess the safety, tolerability, and potential benefit of SPG stimulation inpatients with acute ischemic stroke(AIS). METHODS: Patients with anterior AIS, baseline NIHSS 7-20 and ability to initiate treatment within 24h from stroke onset, were implanted and treated with the SPG stimulation. Patients were followed up for 90 days. Effect was assessed by comparing the patient outcome to a matched population from the NINDS rt-PA trial placebo patients. RESULTS: Ninety-eight patients were enrolled (mean age 57years, mean baseline NIHSS 12 and mean treatment time from stroke onset 19h). The observed mortality rate(12.2%), serious adverse events (SAE)incidence(23.5%) and nature of SAE were within the expected range for the population. The modified intention to treat cohort consisted of 84 patients who were compared to matched patients from the NINDS placebo arm. Patients treated with SPG stimulation had an average mRS lower by 0.76 than the historical controls(CMH test p = 0.001). CONCLUSION: The implantation procedure and the SPG stimulation, initiated within 24hr from stroke onset, are feasible, safe, and tolerable. The results call for a follow-up randomized trial (funded by BrainsGate; clinicaltrials.gov number, NCT03733236).
Assuntos
Isquemia Encefálica , Circulação Cerebrovascular , Terapia por Estimulação Elétrica , Gânglios Parassimpáticos/fisiopatologia , Acidente Vascular Cerebral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Velocidade do Fluxo Sanguíneo , Isquemia Encefálica/fisiopatologia , Isquemia Encefálica/terapia , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/terapiaRESUMO
Dynamic cerebral autoregulation assessed from blood pressure transients can be considerably impaired in severe internal carotid artery (ICA) obstruction. It is unknown whether impaired autoregulation indicates an increased risk of subsequent ischemic events in this situation. 165 patients with ICA stenosis (> 70 %) or occlusion were prospectively followed until anterior circulation stroke, transient ischemic attack, carotid recanalization without prior event, death or study end. Transcranial Doppler sonography was used to determine autoregulation in both middle cerebral arteries from spontaneous blood pressure fluctuations (correlation coefficient indices Dx and Mx) and respiratory- induced 0.1 Hz oscillations (phase). Standard CO(2) reactivity (CO(2)R) was additionally assessed. All indices were classified as impaired vs. preserved according to reference values from 79 agematched controls. During median follow-up of 24.5 months, there were 16 ischemic events over ipsilateral sides. Competing risk analysis revealed a significant predictive effect on ipsilateral ischemic events for impaired Dx (rate ratio 8.2 [95 % confidence interval 1.7-39], p = 0.0079), phase (5.0 [2-13], p = 0.0007) and CO(2)R (9.4 [2.2-40], p = 0.0025). Restricting analysis to severe stenosis alone (n = 103), only impaired phase (rate ratio 8.6 [1.6-45], p = 0.01) remained as a significant predictor. In a continuous statistical model, only Dx and Mx were significant predictors of ischemic events (p = 0.012 and p = 0.016). In conclusion, impaired dynamic cerebral autoregulation indicates an increased risk of subsequent ischemic events in severe obstructive ICA disease. Its clinical application might thus be of help in identifying higher risk patients.
Assuntos
Isquemia Encefálica/etiologia , Encéfalo/fisiopatologia , Doenças das Artérias Carótidas/complicações , Circulação Cerebrovascular/fisiologia , Risco , Idoso , Análise de Variância , Velocidade do Fluxo Sanguíneo/fisiologia , Encéfalo/patologia , Isquemia Encefálica/diagnóstico por imagem , Doenças das Artérias Carótidas/diagnóstico por imagem , Estudos de Casos e Controles , Feminino , Seguimentos , Lateralidade Funcional , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Valores de Referência , Análise de Regressão , Análise Espectral , Ultrassonografia Doppler Transcraniana/métodosRESUMO
BACKGROUND: To investigate whether there is: (1) a specific temporal course of cerebral dysautoregulation in acute ischemic stroke, and (2) a separate detrimental effect of recombinant tissue plasminogen activator (rtPA) on autoregulation dynamics in this situation. METHODS: We studied 16 patients with acute middle cerebral artery (MCA) occlusion and rtPA thrombolysis (intra-arterial or intravenous application, or both). Controls were 71 healthy adults and 11 patients with minor stroke not receiving rtPA. Dynamic autoregulation was recorded from spontaneous fluctuations of blood pressure and MCA flow velocity (transcranial Doppler) using two well-described approaches (index Mx, phase shift). Three measurements were performed (study 1: 20 +/- 9 h of ictus; study 2: 64 +/- 10 h; study 3: 112 +/- 7 h). RESULTS: Two groups of clinical outcome were identified: good (modified Rankin scale
Assuntos
Circulação Cerebrovascular/efeitos dos fármacos , Fibrinolíticos/uso terapêutico , Infarto da Artéria Cerebral Média/tratamento farmacológico , Terapia Trombolítica , Ativador de Plasminogênio Tecidual/uso terapêutico , Doença Aguda , Idoso , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Feminino , Fibrinolíticos/administração & dosagem , Fibrinolíticos/efeitos adversos , Homeostase , Humanos , Infarto da Artéria Cerebral Média/patologia , Infarto da Artéria Cerebral Média/fisiopatologia , Infusões Intra-Arteriais , Infusões Intravenosas , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Proteínas Recombinantes/uso terapêutico , Terapia Trombolítica/efeitos adversos , Fatores de Tempo , Ativador de Plasminogênio Tecidual/administração & dosagem , Ativador de Plasminogênio Tecidual/efeitos adversos , Resultado do Tratamento , Ultrassonografia Doppler TranscranianaRESUMO
BACKGROUND AND PURPOSE: Transesophageal echocardiography (TEE) is the gold standard in detecting high-risk (ie, aortic thrombi) and potential sources (ie, patent foramen ovale [PFO]) of cerebral embolism. We sought to evaluate the additional information and therapeutic impact provided by TEE in stroke patients and to characterize patients in whom TEE is indispensable. METHODS: We included 503 consecutive patients (mean age 62.2 years) with acute brain ischemia. Each patient received TEE and the following routine diagnostics: ultrasound of brain supplying arteries, ECG or Holter-ECG, transthoracic echocardiography, and brain imaging (computed tomography or MRI). Stroke etiology was classified according to the Trial of Org 10172 in Acute Stroke Treatment (TOAST) criteria. High-risk sources in TEE were: aortic thrombi or plaques > or =4 mm, thrombi in left atrial cavity/left atrial appendage, spontaneous echo contrast, and left atrial flow velocity <30 cm/s. Potential sources in TEE were PFO, atrial septal aneurysm, and aortic plaques <4 mm. RESULTS: Stroke etiology was determined by routine diagnostics in 276 of 503 patients (54.9%). Of the remaining 227 patients (undetermined etiology), 212 (93.4%) were candidates for oral anticoagulation (OA). TEE revealed a high-risk source, with indication for OA in 17 of them (8.0%). A potential source leading to OA was found in an additional 48 patients (22.6%). The remaining 147 patients (69.3%) were treated by platelet inhibitors or statins. CONCLUSIONS: TEE strongly influenced secondary prevention and led to OA in one third of our patients with stroke of undetermined etiology. TEE is indispensable in all patients being candidates for OA when routine diagnostics cannot clarify stroke etiology.
Assuntos
Ecocardiografia Transesofagiana/métodos , Isquemia/patologia , Isquemia/terapia , Acidente Vascular Cerebral/patologia , Acidente Vascular Cerebral/terapia , Administração Oral , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/farmacologia , Aorta/patologia , Encéfalo/patologia , Transtornos Cerebrovasculares/diagnóstico , Transtornos Cerebrovasculares/patologia , Ecocardiografia/métodos , Humanos , Embolia Intracraniana/patologia , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Modelos Estatísticos , Risco , Acidente Vascular Cerebral/diagnóstico , Fatores de TempoRESUMO
BACKGROUND AND PURPOSE: A recent study showed a dramatic increase in cerebral hemorrhage comprising atypical locations with low-frequency ultrasound-mediated recombinant tissue plasminogen activator-thrombolysis in humans. Here, we provide a possible explanation for this phenomenon by a side effect observed in a study using the similar ultrasound device. METHODS: The study was originally undertaken to investigate by transcranial Doppler sonography, positron emission tomography and perfusion MRI whether transcranial application of wide-field low-frequency ultrasound (300 kHz) improves cerebral hemodynamics in patients with cerebral small vessel disease. RESULTS: Showing no clear positive effect on cerebral hemodynamics in 4 patients and on cerebral perfusion (positron emission tomography) in 2 patients, the study has been terminated early because of a remarkable side effect in the first patient (a 62 year-old man) undergoing perfusion-MRI: detection of frontoparietal extravasation of Gadolinium contrast agent (applied during MRI perfusion imaging preinsonation) on MRI immediately postinsonation. CONCLUSIONS: Abnormal permeability of the human blood-brain barrier can be induced by wide-field low-frequency insonation. The observed excessive bleeding rate with low-frequency sonothrombolysis might thus be attributable to primary blood-brain barrier disruption by ultrasound.
Assuntos
Barreira Hematoencefálica/efeitos da radiação , Isquemia Encefálica/fisiopatologia , Isquemia Encefálica/terapia , Terapia por Ultrassom/efeitos adversos , Idoso , Isquemia Encefálica/diagnóstico , Circulação Cerebrovascular/efeitos da radiação , Extravasamento de Materiais Terapêuticos e Diagnósticos/etiologia , Lobo Frontal/irrigação sanguínea , Hemodinâmica/efeitos da radiação , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Lobo Parietal/irrigação sanguínea , Tomografia por Emissão de Pósitrons , Ultrassonografia Doppler TranscranianaRESUMO
BACKGROUND AND PURPOSE: We hypothesized that for the prediction or exclusion of aortic thrombi or plaques >or=4 mm, the combination of intima-media thickness (IMT) and distensibility (DC) of the common carotid arteries would be superior to the measurement of IMT alone. METHODS: We prospectively included 208 stroke patients (mean age, 60 years) undergoing transesophageal echocardiography for screening of aortic plaques. IMT and DC were determined by ultrasound, and DC was quantified by measuring blood pressure and the common carotid arteries diameter change on M-mode ultrasound during the cardiac cycle. RESULTS: Negative predictive values of IMT <0.9 mm and DC >or=24x10(-3)/kPa for the exclusion of aortic atheroma >or=4 mm were similar (92.0% and 91.7%, respectively). However, negative predictive values increased to 98.2% and to 100.0% for the exclusion of aortic thrombi when both parameters were combined. Positive predictive values of IMT >or=0.9 mm and DC <24 were lower (46.3%, 41.1%; respectively), but they also increased in combination (54.3%). CONCLUSIONS: Our findings suggest that IMT and DC represent different vessel wall properties and that measuring both parameters provides optimized characterization of carotid atherosclerosis. Combining IMT and DC increases the predictive power of carotid ultrasound, making transesophageal echocardiography dispensable for assessment of the aorta for those with normal carotid arteries and indispensable for those patients with carotid atherosclerosis.
Assuntos
Isquemia Encefálica/patologia , Artérias Carótidas/patologia , Acidente Vascular Cerebral/patologia , Túnica Íntima/patologia , Túnica Média/patologia , Adulto , Idoso , Isquemia Encefálica/diagnóstico por imagem , Artérias Carótidas/diagnóstico por imagem , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Acidente Vascular Cerebral/diagnóstico por imagem , Túnica Íntima/diagnóstico por imagem , Túnica Média/diagnóstico por imagem , UltrassonografiaRESUMO
The phase shift between oscillations of blood pressure (BP) and Doppler middle cerebral artery flow velocity (MCAFV) reflects continuous cerebral autoregulatory action. It is not known whether a similar phase shift exists for cortical hemodynamics ('microvascular level') assessed by near infrared spectroscopy (NIRS) and what the effects are of pathological conditions. This study investigates the phase relations between oscillations of BP, MCAFV and NIRS parameters in 38 healthy older adults and 28 patients with unilateral severe obstructive carotid disease. BP was recorded noninvasively by finger plethysmography. Stable 0.1 Hz oscillations of all hemodynamic parameters were induced by regular breathing at a rate of 6/min. Basic results were that: (1) BP-induced cortical microvascular oscillations (NIRS) follow those of macrovascular oscillations (MCAFV) with a phase of 80-90 degrees (corresponding to 2-2.5 s at 0.1 Hz), most likely reflecting a transit time phenomenon; (2) oxy- and deoxyhemoglobin thereby oscillate in counterphase; (3) hemodynamic compromise in carotid obstruction leads to (a) delayed NIRS oscillations in comparison to BP which are highly correlated to a shorter phase lead of MCAFV against BP and (b) a decoupling of the oxy-/deoxyhemoglobin counterphase to 240 degrees . Cortical hemodynamic responses to BP oscillations follow specific phase relationships due to cerebral autoregulatory action and circulatory transit times. With hemodynamic impairment, as in unilateral carotid obstruction, these phases are significantly changed reflecting disturbed autoregulation.
Assuntos
Relógios Biológicos/fisiologia , Pressão Sanguínea/fisiologia , Circulação Cerebrovascular/fisiologia , Microcirculação/fisiologia , Artéria Cerebral Média/fisiologia , Telencéfalo/irrigação sanguínea , Idoso , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/fisiopatologia , Transtornos Cerebrovasculares/diagnóstico por imagem , Transtornos Cerebrovasculares/fisiopatologia , Feminino , Homeostase/fisiologia , Humanos , Fluxometria por Laser-Doppler/métodos , Masculino , Microcirculação/diagnóstico por imagem , Pessoa de Meia-Idade , Artéria Cerebral Média/diagnóstico por imagem , Pletismografia , Valor Preditivo dos Testes , Fatores de Risco , Telencéfalo/diagnóstico por imagem , Telencéfalo/fisiologia , UltrassonografiaRESUMO
BACKGROUND AND PURPOSE: Impaired cerebrovascular reserve capacity (CVC) is a risk factor for ischemic events in patients with high-grade carotid stenosis and occlusion. In this study, the CVC in response to a CO2 challenge was evaluated with blood oxygen level-dependent (BOLD) MRI and the results compared with those of a transcranial Doppler CO2 tests. METHODS: A T2*-weighted single-shot multigradient echo-planar imaging sequence was used to determine cerebral CO2 reactivity. T2* values were calculated for each pixel at rest and during a challenge with 7% CO2, and a reference function was fitted to the T2* time courses. Whole-brain color-coded DeltaT2* parameter maps were calculated and visually evaluated for regional differences. Additionally, a region-of-interest analysis was undertaken. Average values for DeltaT2* normalized to changes in end-tidal PCO2 were calculated. RESULTS: Color parameter maps showed areas of decreased BOLD effect within the internal carotid artery territory in 12 of 13 hemispheres with impaired CVC in transcranial Doppler CO2 test. Regional normalized DeltaT2* was highly correlated with changes of middle cerebral artery blood flow velocity in transcranial Doppler CO2 test. Normalized DeltaT2* was significantly reduced in hemispheres with impaired CVC in transcranial Doppler (P<0.0001). CONCLUSIONS: BOLD MRI can easily be included in routine MRI exams. The technique is robust and yields diagnostic information concerning the cerebrovascular reserve.
Assuntos
Sangue/metabolismo , Dióxido de Carbono/química , Doenças das Artérias Carótidas/patologia , Imageamento por Ressonância Magnética/métodos , Oxigênio/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Encéfalo/patologia , Dióxido de Carbono/metabolismo , Artéria Carótida Interna/patologia , Imagem Ecoplanar , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Estatística como Assunto , Fatores de Tempo , Ultrassonografia DopplerRESUMO
The objective of the present study was to identify predictors of left atrial spontaneous echocardiographic contrast (SEC) or thrombus in patients with stroke with sinus rhythm and left ventricular dysfunction. Of 500 consecutive patients with stroke, 48 with sinus rhythm and reduced left ventricular ejection fractions (EFs) < or =45% were examined. Ten patients presented with SEC or thrombus. The patients with SEC or thrombus had larger left atrial diameters (47 +/- 4 vs 42 +/- 6 mm, p <0.05), smaller EFs (30 +/- 9% vs 38 +/- 8%, p <0.01), and slower left atrial appendage (LAA) flow velocities (42 +/- 13 vs 61 +/- 17 cm/s, p <0.01). Multivariate analysis identified EF < or =35% and LAA flow velocity < or =55 cm/s as predictors of SEC or thrombus (p <0.05). Patients with stroke with sinus rhythm and moderate- to high-grade reduction of the left ventricular EF represent a risk group for a left atrial source of embolism and should undergo transesophageal echocardiography.
Assuntos
Apêndice Atrial/diagnóstico por imagem , Meios de Contraste/efeitos adversos , Ecocardiografia Transesofagiana/métodos , Embolia Intracraniana/etiologia , Volume Sistólico/fisiologia , Acidente Vascular Cerebral/complicações , Disfunção Ventricular Esquerda/complicações , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Apêndice Atrial/fisiopatologia , Ecocardiografia Transesofagiana/efeitos adversos , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologiaRESUMO
Giant cell arteritis (GCA) is known to affect the extracranial part of the vertebral arteries. Bilateral vertebral artery occlusion (BVAO) is a rare but serious neurologic condition. We report 3 patients with autopsy-proven (2 patients) or clinically diagnosed (1 patient) GCA causing BVAO. A review of the literature concerning BVAO revealed 5 other cases of BVAO resulting from GCA and 110 cases with underlying arteriosclerotic disease. Our 3 patients (mean age, 66 yr; range, 60-78 yr) with BVAO resulting from GCA all had initial severe headache followed by the onset of stepwise progressive, partly side-alternating neurologic deficits due to bilateral infarctions in the vertebrobasilar circulation territory. This course, more accelerated in BVAO due to GCA than in BVAO of arteriosclerotic origin, seems to be a typical, if not particular, clinical syndrome. BVAO was the first clinical manifestation of GCA in 1 of our patients and in 1 published case. From a clinical view, BVAO resulting from GCA differs from BVAO of arteriosclerotic origin by the much higher mortality rate (75% versus 19%, respectively), the presence of headache (100% versus 22%), fever (50% versus 0%), and elevated erythrocyte sedimentation rate (ESR in all GCA cases >45 mm/h; no data in the arteriosclerotic patient group), but not by the neurologic signs themselves. Therapy of BVAO resulting from GCA is purely empiric. In view of the serious prognosis, we propose treatment with intravenous high-dose glucocorticoids and additional immunosuppression with cyclophosphamide; the use of anticoagulation depends on the individual patient's estimated risk-benefit profile. Although BVAO due to GCA is rare, physicians and especially rheumatologists or neurologists should be aware of this entity because of its high mortality in patients without immediate introduction of a high-dose immunosuppressive therapy. Suspicion of GCA should arise in a patient aged over 50 years with no other vascular risk factors suffering from bilateral symptoms of ischemia in the vertebrobasilar territory, with a quickly progressing stepwise course and with headache, fever, or history of myalgia. ESR and temporal artery biopsy should be performed without delay. Early diagnosis of GCA is necessary for immediate initiation of intensive antiinflammatory and immunosuppressive treatment, without which progressive deterioration and systemic involvement are likely to be fatal.
Assuntos
Arterite de Células Gigantes/complicações , Insuficiência Vertebrobasilar/etiologia , Idoso , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Insuficiência Vertebrobasilar/diagnóstico , Insuficiência Vertebrobasilar/patologiaRESUMO
OBJECTIVE: To evaluate findings for patients with carotid cavernous fistulae or dural arteriovenous fistulae (AVFs) who underwent transvenous embolization via different transvenous approaches. METHODS: Retrospective analysis of data for 31 patients (age range, 17-81 yr; mean age, 59.3 yr) with carotid cavernous fistulae (n = 6) or dural AVFs (cavernous sinus [CS], n = 11; transverse/sigmoid sinus, n = 14) was performed. The AVFs were treated with coils via different transvenous approaches, in 56 procedures. Doppler ultrasonography and time-resolved, two-dimensional, magnetic resonance projection angiography were performed to confirm the treatment. The mean clinical follow-up period was 32.5 months. RESULTS: A total of 34 transvenous procedures were performed for 17 AVFs of the CS. Eleven patients with AVFs of the CS (63%) were cured with respect to clinical symptoms, and six patients experienced improvement (37%). The approach via the internal jugular vein and inferior petrosal sinus (n = 15) was possible in 60% of cases, with complete occlusion of the fistula in 78% of cases. With the approach via the facial vein (n = 8), there was a 50% success rate. The superior ophthalmic vein approach (n = 5) was associated with a high rate of technical success (100%), with a rate of complete fistula occlusion of 80%. We encountered complications, with transient morbidity, in four cases (23.5%). For 14 dural AVFs of the transverse/sigmoid sinus, 22 transvenous procedures were performed; 12 patients were cured (85.7%) and 2 experienced improvement (14.3%). The technical success rate was 86%, with complete occlusion in 42% of cases. Minor complications occurred in six cases (42.9%) but did not lead to permanent morbidity. CONCLUSION: Transvenous treatment of CS and transverse/sigmoid sinus AVFs can be effective if all transvenous approaches, including combined surgical/endovascular approaches, are considered.
Assuntos
Fístula Carótido-Cavernosa/terapia , Malformações Vasculares do Sistema Nervoso Central/terapia , Embolização Terapêutica , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Fístula Carótido-Cavernosa/diagnóstico por imagem , Malformações Vasculares do Sistema Nervoso Central/diagnóstico por imagem , Angiografia Cerebral , Embolização Terapêutica/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , VeiasRESUMO
Basilar artery (BA) stenting is an emerging technique with promising results in revascularization of severe arteriosclerotic stenoses. Because of the limitations associated with other noninvasive techniques, we applied transcranial color-coded sonography (TCCS) in the follow-up. Successful stent application in two cases of acute basilar occlusion caused by thrombosis on pre-existing severe midbasilar stenoses was initially confirmed by angiography. Later recanalization was controlled noninvasively by magnetic resonance angiography (MRA), computed tomographic angiography (CTA) and TCCS. Ultrasound (US) was performed through the transtemporal bone window; a contrast-enhancing agent had to be used in one case. TCCS showed an orthograde flow in the distal BA in both patients without signs of severe stenoses. Transtemporal TCCS was demonstrated to be a noninvasive bedside technique in monitoring the patency of the BA after stenting.
Assuntos
Artéria Basilar/diagnóstico por imagem , Artéria Basilar/cirurgia , Stents , Ultrassonografia Doppler Transcraniana , Insuficiência Vertebrobasilar/diagnóstico por imagem , Insuficiência Vertebrobasilar/cirurgia , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: To assess the usefulness of transcranial Doppler CO2 reactivity (CO2R) for prediction of ipsilateral ischemic stroke in carotid artery stenosis and occlusion with a meta-analysis of prospective studies based on individual patient data. METHODS: We searched Medline, Biosis Previews, Science Citation Index, The Cochrane Library, and EMBASE for studies in which patients with severe carotid artery stenosis or occlusion underwent Doppler CO2R testing (inhalation of CO2 or breath-holding) and were prospectively followed for ipsilateral ischemic stroke. Individual data from 754 patients from 9 studies were included. We used percentage cerebral blood flow velocity increase (pCi) during hypercapnia as the primary CO2R measure, and defined impaired reactivity as pCi <20% increase. RESULTS: In a multiple regression model, impaired CO2R was independently associated with an increased risk of ipsilateral ischemic stroke (hazard ratio [HR] 3.69; confidence interval [CI] 2.01, 6.77; p < 0.0001). Risk prediction was similar for recently symptomatic vs asymptomatic patients. Using continuous values of pCi, a significant association between decreasing pCi and increasing risk of ipsilateral stroke was found: HR of 1.64 (95% CI 1.33, 2.02; p < 0.0001) per 10% decrease in pCi. For patients with asymptomatic internal carotid artery stenosis only (n = 330), a comparable stroke risk prediction was found: increasing HR 1.95 (95% CI 1.26, 3.04; p = 0.003) per 10% decrease in pCi. CONCLUSIONS: This analysis supports the usefulness of CO2R in risk prediction for patients with severe carotid artery stenosis or occlusion, both in recently symptomatic and asymptomatic patients. Further studies should evaluate whether treatment strategies in asymptomatic patients based on CO2R could improve patient outcomes.