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1.
Stress Health ; 35(5): 675-680, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31430036

RESUMO

The aim of this work was to test the hypothesis that the discrepancy between factual and counterfactual subjective social status (DCS) relates to psychological distress beyond the effect of current (i.e., factual) subjective and objective social status. Participants were 124 single mothers (Study 1) and 310 persons who have become unemployed (Study 2). In both samples, higher DCS was related to more severe symptoms of stress and depression beyond the effect of current subjective and objective social status. Upward counterfactual thinking might be an additional psychological factor in the relationship between social inequality and health in socially deprived individuals.

2.
Clin Chem ; 63(1): 394-402, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27903616

RESUMO

AIMS: Serial measurements of high-sensitivity troponin are used to rule out acute myocardial infarction (AMI) with an assay specific cutoff at the 99th percentile. Here, we evaluated the performance of a single admission troponin with a lower cutoff combined with a low risk electrocardiogram (ECG) to rule out AMI. METHODS: Troponin I measured with a high-sensitivity assay (hs-TnI) was determined at admission in 1040 patients presenting with suspected AMI (BACC study). To rule out AMI we calculated the negative predictive value (NPV) utilizing the optimal hs-TnI cutoff combined with a low risk ECG. The results were validated in 3566 patients with suspected AMI [2-h Accelerated Diagnostic Protocol to Assess Patients With Chest Pain Symptoms Using Contemporary Troponins as the Only Biomarker (ADAPT) studies]. Patients were followed for 6 or 12 months. RESULTS: 184 of all patients were diagnosed with AMI. An hs-TnI cutoff of 3 ng/L resulted in a NPV of 99.3% (CI 97.3-100.0), ruling out 35% of all non-AMI patients. Adding the information of a low risk ECG resulted in a 100% (CI 97.5-100.0) NPV (28% ruled out). The 2 validation cohorts replicated the high NPV of this approach. The follow-up mortality in the ruled out population was low (0 deaths in BACC and Stenocardia, 1 death in ADAPT). CONCLUSIONS: A single hs-TnI measurement on admission combined with a low risk ECG appears to rule out AMI safely without need for serial troponin testing. TRIAL REGISTRATION: www.clinicaltrials.gov (NCT02355457).


Assuntos
Eletrocardiografia , Infarto do Miocárdio/diagnóstico , Troponina I/sangue , Doença Aguda , Idoso , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue
3.
Clin Hemorheol Microcirc ; 64(3): 255-266, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27858702

RESUMO

INTRODUCTION: Flow-mediated dilation (FMD) quantifies endothelium-dependent vasomotor responses to short-term increases in blood flow. Low-flow mediated vasoconstriction (L-FMC) has been more recently introduced as additional measure of endothelial function, and its relationship with changes in blood flow, cardiovascular risk factors and FMD ha∧s been less well characterized. MATERIALS AND METHODS: We evaluated radial artery FMD and L-FMC along with the changes in blood flow and shear rate/stress in 584 patients with known or suspected coronary artery disease (72.9% men, mean age 67+/-11 years). Baseline blood flow and shear rate showed a modest association with radial artery FMD and L-FMC (R2 = 0.04 and R2 = 0.02, P < 0.0001). Resting diameter showed a stronger association with FMD but not with L-FMC (R2 = 0.11, P < 0.0001 and R2 = 0.005, P = 0.09). Analysis with generalized additive models showed that age, sex and presence and extent of coronary artery disease were strongly related to both endothelial function measures (P < 0.001 for both), but they explained only 12.4% and 10.1% of the variance in L-FMC and FMD. When the corresponding changes in blood flow were added to these statistical models, the % of variance explained raised to 20.4% and 17.7% for L-FMC and FMD. L-FMC was a strong predictor of FMD even after correction for the changes in blood flow. DISCUSSION: Changes in blood flow are the most important determinants of both L-FMC and FMD. These observations support the concept that both FMD and L-FMC measure endothelium-dependent, shear-induced, vasomotion.


Assuntos
Endotélio Vascular/fisiopatologia , Vasoconstrição/imunologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional , Fatores de Risco , Estresse Mecânico
4.
JAMA Cardiol ; 1(4): 397-404, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27438315

RESUMO

IMPORTANCE: Rapid and accurate diagnosis of acute myocardial infarction (AMI) currently constitutes an unmet need. OBJECTIVE: To test a 1-hour diagnostic algorithm to diagnose AMI using a high-sensitivity troponin I assay with a new cutoff level of 6 ng/L. DESIGN, SETTING, AND PARTICIPANTS: The Biomarkers in Acute Cardiac Care study is a prospective study that investigated the application of the troponin I assay for the diagnosis of AMI in 1040 patients presenting to the emergency department with acute chest pain from July 19, 2013, to December 31, 2014. Results were validated in 2 independent cohorts of 4009 patients. Final follow-up was completed on July 1, 2015, and data were assessed from July 2 to December 15, 2015. EXPOSURE: Acute chest pain suggestive of AMI. MAIN OUTCOMES AND MEASURES: Accurate diagnosis or exclusion of AMI and 12-month mortality in patients with acute chest pain. RESULTS: Of the 1040 patients included from the study cohort, 673 (64.7%) were male and had a median age of 65 (interquartile range, 52-75) years. With application of a low troponin I cutoff value of 6 ng/L, the rule-out algorithm showed a high negative predictive value of 99.8% (95% CI, 98.6%-100.0%) after 1 hour for non-ST-segment elevation MI type 1. The 1-hour approach was comparable to a 3-hour approach. Similarly, a rule-in algorithm based on troponin I levels provided a high positive predictive value with 82.8% (95% CI, 73.2%-90.0%). Moreover, application of the cutoff of 6 ng/L resulted in lower follow-up mortality (1.0%) compared with the routinely used 99th percentile (3.7%) for this assay. Two independent cohorts further validated the performance of this algorithm with high negative and positive predictive values. CONCLUSIONS AND RELEVANCE: Patients with possible AMI can be triaged within 1 hour after admission with no loss of safety compared with a 3-hour approach, when a low and sensitive cutoff is applied. This concept enables safe discharge or rapid treatment initiation after 1 hour.


Assuntos
Algoritmos , Biomarcadores/sangue , Infarto do Miocárdio/diagnóstico , Troponina I/sangue , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Valores de Referência , Sensibilidade e Especificidade
5.
Clin Hemorheol Microcirc ; 52(2-4): 235-43, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22960299

RESUMO

Previous studies from our and other laboratories have demonstrated the existence of a clear relationship between different measures of endothelial function and the extent of coronary atherosclerosis. The relationship between endothelial function and carotid intima-media thickness has not been extensively investigated. Endothelial function using radial artery flow-mediated constriction (L-FMC) and dilation (FMD) was assessed in 513 consecutive patients undergoing diagnostic coronary angiography. Intima-media thickness of both carotid arteries was also measured. IMT was greater in patients with diabetes, males, those with body mass index >30, and in those older than 65 years (all p < 0.05). There was a strong correlation between age and IMT (p < 0.0001). Hypercholesterolemia and a family history for cardiovascular disease had no impact on IMT. In contrast, the relationship between either L-FMC or FMD and IMT was weak at best (p = 0.008 for the relationship between L-FMC and IMT, p = 0.13 for the relationship between FMD and IMT). There was a positive correlation between IMT and resting radial artery diameter (p = 0.008). IMT increased with the extent of coronary artery disease, but this trend did not reach statistical significance (p = 0.07). Resting (L-FMC), but not recruitable (FMD) endothelial function correlates with the extent of subclinical carotid atherosclerosis. This correlation is however weaker in comparison to that with age.


Assuntos
Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/diagnóstico por imagem , Espessura Intima-Media Carotídea , Endotélio Vascular/diagnóstico por imagem , Idoso , Artérias Carótidas/patologia , Doenças das Artérias Carótidas/sangue , Doenças das Artérias Carótidas/patologia , Endotélio Vascular/fisiopatologia , Feminino , Humanos , Masculino , Fatores de Risco
6.
Clin Hemorheol Microcirc ; 52(2-4): 255-66, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22975942

RESUMO

BACKGROUND: Coronary (micro)vascular resistance is regulated by the complex interplay of several factors. Two potentially important determinants include endothelial function and the rheological properties of blood. However, their impact on the control of the coronary resistance vasculature is poorly understood. METHODS: The corrected Thrombolysis In Myocardial Infarction frame count (TIMIfc, an index of coronary flow velocity), conduit artery endothelial function, intima-media thickness of the common carotid artery and complete blood counts were measured in 145 patients undergoing elective coronary angiography. Patients with obstructive coronary artery disease or systemic conditions thought to be associated with microvascular disease were excluded from the analysis. RESULTS: There was a strong correlation between the TIMIfc measured in the three main coronary artery distributions (R values between 0.71 and 0.85, P < 0.00001). The TIMIfc was higher in males (P < 0.05), but there was no association with traditional risk factors for coronary artery disease (all P > 0.1). There was a correlation between TIMIfc and L-FMC, a parameter of resting endothelial function (R = 0.33, P < 0.0005). TIMIfc also correlated with mean platelet volume (a marker of platelet activation, R = 0.33, P < 0.001), and hematocrit (R = 0.33, P = 0.0002). There was no correlation between TIMIfc and carotid intima-media thickness and the degree of coronary atherosclerosis. Logistic regression analysis showed that L-FMC and hemorheological variables may explain as much as 19% of the variability in TIMIfc. CONCLUSIONS: Resting peripheral endothelial function, as well as parameters of platelet function, correlate with coronary TIMIfc. These data emphasize the existence of an association between endothelial function, hemorheological variables and coronary blood flow velocity.


Assuntos
Circulação Coronária/fisiologia , Endotélio Vascular/fisiologia , Idoso , Velocidade do Fluxo Sanguíneo , Espessura Intima-Media Carotídea , Angiografia Coronária , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/fisiopatologia , Endotélio Vascular/diagnóstico por imagem , Endotélio Vascular/fisiopatologia , Feminino , Hemorreologia , Humanos , Masculino , Ativação Plaquetária , Fatores de Risco
7.
Eur Heart J ; 33(3): 363-71, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21920964

RESUMO

AIMS: A number of risk factors for atherosclerosis have been identified, but it remains difficult, on an individual patient basis, to predict how these factors interact in determining the development of coronary artery disease (CAD). It also remains unclear whether the study of endothelial function provides information that is additive to that of traditional risk factors. METHODS AND RESULTS: Flow-mediated dilation (FMD) and low-flow-mediated constriction (L-FMC) were measured in 451 consecutive patients before coronary angiography. Low-flow-mediated constriction (P< 0.0001) and FMD (P=0.0005) progressively decreased with the number of diseased vessels, and L-FMC showed a significant linear correlation with the SYNTAX score (R=0.38; P< 0.0001). Logistic regression analysis confirmed the association between endothelial function parameters and CAD (P=0.001 for L-FMC, P=0.02 for FMD). Receiver operating characteristic analysis demonstrated that the addition of L-FMC alone and of the combination of FMD and L-FMC improved the predictive power of a model based on traditional risk factors for CAD (area under the curve of the risk factor model=0.716; risk factor model + FMD=0.734, P=0.1 compared with risk factor model; risk factor model + L-FMC=0.771, P=0.004; risk factor model + L-FMC + FMD=0.779, P=0.002). Reclassification statistics showed that the introduction of FMD to the model based on the traditional risk factors correctly reclassified an additional 5% of patients, and that the introduction of L-FMC net correctly reclassified 19% of the patients. There was no correlation between different parameters of endothelial function. CONCLUSION: Endothelial function assessment provides modest but statistically significant additional information in predicting the presence of CAD.


Assuntos
Doença da Artéria Coronariana/fisiopatologia , Endotélio Vascular/fisiopatologia , Vasoconstrição/fisiologia , Vasodilatação/fisiologia , Idoso , Constrição , Doença da Artéria Coronariana/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Fatores de Risco
8.
Clin Hemorheol Microcirc ; 49(1-4): 261-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22214697

RESUMO

The slow coronary flow phenomenon (SCF), a condition described by the presence of inappropriate delay in the progression of intracoronary contrast during angiography in the absence of stenoses, has been shown in some patients presenting with chest pain. While several conditions leading to "secondary" slow flow are known, there are no definitive conclusions regarding the exact pathogenesis of "primary" SCF. The present paper outlines the mechanisms that may lead to SCF, emphasizing the role of hemorheological and vascular factors in the pathogenesis of this phenomenon. Small vessel dysfunction has been proposed in the pathogenesis of SCF since the first description of this syndrome in 1972. Abnormalities in coronary microvascular function result from increased microvascular resistances and impaired endothelial release of vasoactive substances, especially in production and bioavailability of endothelium derived NO. Inflammatory conditions (increased levels of C-reactive protein, interleukin-6 and adhesion molecules) and metabolic abnormalities such as impaired glycemic control, hyperuricemia and elevated serum gamma-glutamyltransferase were also found to contribute to microvascular dysfunction in patients with SCF. New studies have also indicated that increased blood viscosity and one of its major determinants, erythrocyte aggregation, is associated with the SCF. Rheological variables play a role in the control of shear stress and contribute to blood flow velocity changes. Although platelets do not have a significant influence on blood viscosity, it has been demonstrated that they are involved in the development of SCF. Increased mean platelet volume (MPV), an indicator of platelet activation and platelet aggregability is also significantly higher in patients with SCF compared with patients with normal coronary flow.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Dor no Peito/fisiopatologia , Circulação Coronária/fisiologia , Hemorreologia , Microvasos/fisiopatologia , Arginina/análogos & derivados , Arginina/sangue , Dor no Peito/sangue , Dor no Peito/tratamento farmacológico , Circulação Coronária/efeitos dos fármacos , Diagnóstico Diferencial , Endotélio Vascular/fisiopatologia , Feminino , Humanos , Hiper-Homocisteinemia/sangue , Hiper-Homocisteinemia/fisiopatologia , Inflamação/fisiopatologia , Masculino , Microvasos/efeitos dos fármacos , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/fisiopatologia , Óxido Nítrico/fisiologia , Ativação Plaquetária , Síndrome , Resistência Vascular/efeitos dos fármacos , Vasodilatadores/farmacologia , Vasodilatadores/uso terapêutico
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