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2.
Clin Nutr ; 38(1): 1-9, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30181091

RESUMO

RATIONALE: This initiative is focused on building a global consensus around core diagnostic criteria for malnutrition in adults in clinical settings. METHODS: In January 2016, the Global Leadership Initiative on Malnutrition (GLIM) was convened by several of the major global clinical nutrition societies. GLIM appointed a core leadership committee and a supporting working group with representatives bringing additional global diversity and expertise. Empirical consensus was reached through a series of face-to-face meetings, telephone conferences, and e-mail communications. RESULTS: A two-step approach for the malnutrition diagnosis was selected, i.e., first screening to identify "at risk" status by the use of any validated screening tool, and second, assessment for diagnosis and grading the severity of malnutrition. The malnutrition criteria for consideration were retrieved from existing approaches for screening and assessment. Potential criteria were subjected to a ballot among the GLIM core and supporting working group members. The top five ranked criteria included three phenotypic criteria (non-volitional weight loss, low body mass index, and reduced muscle mass) and two etiologic criteria (reduced food intake or assimilation, and inflammation or disease burden). To diagnose malnutrition at least one phenotypic criterion and one etiologic criterion should be present. Phenotypic metrics for grading severity as Stage 1 (moderate) and Stage 2 (severe) malnutrition are proposed. It is recommended that the etiologic criteria be used to guide intervention and anticipated outcomes. The recommended approach supports classification of malnutrition into four etiology-related diagnosis categories. CONCLUSION: A consensus scheme for diagnosing malnutrition in adults in clinical settings on a global scale is proposed. Next steps are to secure further collaboration and endorsements from leading nutrition professional societies, to identify overlaps with syndromes like cachexia and sarcopenia, and to promote dissemination, validation studies, and feedback. The diagnostic construct should be re-considered every 3-5 years.


Assuntos
Internacionalidade , Desnutrição/diagnóstico , Avaliação Nutricional , Adulto , Consenso , Humanos , Liderança , Estado Nutricional , Sociedades Científicas
3.
J Cachexia Sarcopenia Muscle ; 10(1): 207-217, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30920778

RESUMO

RATIONALE: This initiative is focused on building a global consensus around core diagnostic criteria for malnutrition in adults in clinical settings. METHODS: In January 2016, the Global Leadership Initiative on Malnutrition (GLIM) was convened by several of the major global clinical nutrition societies. GLIM appointed a core leadership committee and a supporting working group with representatives bringing additional global diversity and expertise. Empirical consensus was reached through a series of face-to-face meetings, telephone conferences, and e-mail communications. RESULTS: A two-step approach for the malnutrition diagnosis was selected, i.e., first screening to identify "at risk" status by the use of any validated screening tool, and second, assessment for diagnosis and grading the severity of malnutrition. The malnutrition criteria for consideration were retrieved from existing approaches for screening and assessment. Potential criteria were subjected to a ballot among the GLIM core and supporting working group members. The top five ranked criteria included three phenotypic criteria (weight loss, low body mass index, and reduced muscle mass) and two etiologic criteria (reduced food intake or assimilation, and inflammation or disease burden). To diagnose malnutrition at least one phenotypic criterion and one etiologic criterion should be present. Phenotypic metrics for grading severity as Stage 1 (moderate) and Stage 2 (severe) malnutrition are proposed. It is recommended that the etiologic criteria be used to guide intervention and anticipated outcomes. The recommended approach supports classification of malnutrition into four etiology-related diagnosis categories. CONCLUSION: A consensus scheme for diagnosing malnutrition in adults in clinical settings on a global scale is proposed. Next steps are to secure further collaboration and endorsements from leading nutrition professional societies, to identify overlaps with syndromes like cachexia and sarcopenia, and to promote dissemination, validation studies, and feedback. The diagnostic construct should be re-considered every 3-5 years.


Assuntos
Desnutrição/diagnóstico , Adulto , Índice de Massa Corporal , Consenso , Ingestão de Alimentos , Saúde Global , Humanos , Fenótipo , Sarcopenia/diagnóstico , Redução de Peso
5.
Stud Health Technol Inform ; 133: 238-45, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18431857

RESUMO

There is increasing evidence nowadays that diseases or conditions, like osteoporosis (OP), which are conventionally defined in terms of bone quantity/mass, are also associated with concomitant changes at the bone matrix level. The present study examined the composition, density and mineral content of OP cancellous bone at the tissue level and the hardness values at the trabecular level to establish correlations between these variables. The results showed that changes in porosity (Bone volume/Tissue volume) are accompanied by changes in mineral content and in the hardness of individual trabeculae. In other words in OP there are both quantitative and qualitative effects that take place with the progress of this condition.


Assuntos
Matriz Óssea/fisiopatologia , Fêmur/fisiologia , Osteoporose/fisiopatologia , Idoso , Envelhecimento , Fenômenos Biomecânicos , Densidade Óssea , Feminino , Humanos , Pessoa de Meia-Idade , Porosidade
6.
J Hum Hypertens ; 31(6): 376-381, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28252041

RESUMO

Hypertension is one of the leading risk factors for morbidity and mortality in patients with cardiovascular and cerebrovascular diseases and renal impairment. It also leads to target organ damage (TOD), which worsens organ function and the patient's clinical status. Reactive oxygen species (ROS)-mediated oxidative stress may contribute significantly to TOD in patients with hypertension. NO (nitric oxide) is a paracrine factor derived from endothelial cells that has been shown to alleviate ROS-mediated oxidative damage. Nebivolol is a third-generation ß-blocker with vasodilator activity, both actions contributing to decreased blood pressure in hypertensive patients. Its vasodilatory function is mediated by the endothelial l-arginine NO pathway. Nebivolol increases the bioavailability of NO in the vasculature. Its efficacy and safety profile is comparable to other commonly used antihypertensive agents. In this article, we review the current literature to understand TOD secondary to oxidative stress in patients with hypertension and the role of nebivolol in its prevention. A better understanding of the underlying mechanisms by which nebivolol reduces ROS-mediated TOD will not only help in the development of targeted therapies but may also improve health outcomes in hypertensive patients.


Assuntos
Antagonistas de Receptores Adrenérgicos beta 1/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Antioxidantes/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Hipertensão/tratamento farmacológico , Nebivolol/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Vasodilatadores/uso terapêutico , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Endotélio Vascular/fisiopatologia , Humanos , Hipertensão/complicações , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Óxido Nítrico/metabolismo
7.
Cochrane Database Syst Rev ; (1): CD003838, 2006 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-16437464

RESUMO

BACKGROUND: Chronic heart failure is a major cause of morbidity and mortality world-wide. Diuretics are regarded as the first-line treatment for patients with congestive heart failure since they provide symptomatic relief. The effects of diuretics on disease progression and survival remain unclear. OBJECTIVES: To assess the harms and benefits of diuretics for chronic heart failure SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (Issue 2 2004), MEDLINE 1966-2004, EMBASE 1980-2004 and HERDIN database. We hand searched pertinent journals and reference lists of papers were inspected. We also contacted manufacturers and researchers in the field. SELECTION CRITERIA: Only double-blinded randomised controlled trials of diuretic therapy comparing one diuretic with placebo, or one diuretic with another active agent (e.g. ACE inhibitors, digoxin) in patients with chronic heart failure were eligible for inclusion. DATA COLLECTION AND ANALYSIS: Two reviewers independently abstracted the data and assessed the eligibility and methodological quality of each trial. Extracted data were entered into the Review Manager 4.2 computer software, and analysed by determining the odds ratio for dichotomous data, and difference in means for continuous data, of the treated group compared with controls. The likelihood of heterogeneity of the study population was assessed by the Chi-square test. If there was no evidence of statistical heterogeneity and pooling of results was clinically appropriate, a combined estimate was obtained using the fixed-effects model. MAIN RESULTS: We included 14 trials (525 participants), 7 were placebo-controlled, and 7 compared diuretics against other agents such as ACE inhibitors or digoxin. We analysed the data for mortality and for worsening heart failure. Mortality data were available in 3 of the placebo-controlled trials (202 participants). Mortality was lower for participants treated with diuretics than for placebo, odds ratio (OR) for death 0.24, 95% confidence interval (CI) 0.07 to 0.83; P = 0.02. Admission for worsening heart failure was reduced in those taking diuretics in two trials (169 participants), OR 0.07 (95% CI 0.01 to 0.52; P = 0.01). In four trials comparing diuretics to active control (91 participants), diuretics improved exercise capacity in participants with CHF, difference in means WMD 0.72 , 95% CI 0.40 to 1.04; P < 0.0001. AUTHORS' CONCLUSIONS: The available data from several small trials show that in patients with chronic heart failure, conventional diuretics appear to reduce the risk of death and worsening heart failure compared to placebo. Compared to active control, diuretics appear to improve exercise capacity.


Assuntos
Diuréticos/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
8.
Circulation ; 104(19): 2324-30, 2001 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-11696473

RESUMO

BACKGROUND: In chronic heart failure (CHF), overactivation of ergoreceptors (afferents sensitive to the metabolic effects of muscular work) may be a link between peripheral changes, sympathetic overactivation, and increased hemodynamic and ventilatory responses to exercise. The relationship between ergoreceptors, autonomic changes, and the progression of the syndrome has not yet been studied. METHODS AND RESULTS: Thirty-eight stable CHF patients (age, 57+/-1 years; ejection fraction, 26+/-2%) were compared with 12 age-matched normal control subjects. The ergoreflex contribution to the ventilatory and hemodynamic responses to exercise, together with peripheral and central chemoreceptor sensitivity, arterial baroreflex sensitivity, plasma norepinephrine, epinephrine, and heart rate variability, were measured. Enhanced ergoreflex effects on ventilation (78+/-2% versus 50+/-8%), peripheral chemosensitivity (0.6+/-0.4 versus 0.2+/-0.1 L/min per percent SaO(2)), and central chemosensitivity (2.9+/-0.2 versus 2.0+/-0.2 L. min(-1). mm Hg(-1)) and an impaired baroreflex function (4.1+/-0.6 versus 9.1+/-5.6 ms/mm Hg) were confirmed in CHF compared with control subjects (P<0.01 in all comparisons). Ergoreceptor overactivity was associated with a worse symptomatic state (NYHA class, P<0.05), lower exercise tolerance (peak VO(2), P<0.05), and pronounced exercise hyperventilation (VE/VCO(2), P<0.01). It was also a strong predictor of increased central chemosensitivity (independently of clinical parameters), baroreflex impairment, and sympathetic activation (plasma catecholamines and heart rate variability indexes; all P<0.05). In multivariate analysis, among all reflexes studied, the ventilatory component of the ergoreflex was the only independent predictor of peak VO(2) and VE/VCO(2). CONCLUSIONS: In CHF, overactivation of the ergoreflex is associated with abnormal cardiorespiratory reflex control, independently of clinical severity. Among impaired reflexes, overactivation of the ergoreflex is an important determinant of exercise hyperventilation and reduced exercise tolerance.


Assuntos
Barorreflexo , Células Quimiorreceptoras/fisiopatologia , Metabolismo Energético , Insuficiência Cardíaca/fisiopatologia , Respiração , Sistema Nervoso Autônomo/fisiopatologia , Doença Crônica , Progressão da Doença , Eletrocardiografia , Metabolismo Energético/fisiologia , Epinefrina/sangue , Teste de Esforço , Feminino , Testes de Função Cardíaca , Frequência Cardíaca , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Músculos/metabolismo , Neurônios Aferentes , Norepinefrina/sangue , Estudos Prospectivos , Análise de Regressão , Resistência Vascular
9.
Circulation ; 102(18): 2214-21, 2000 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-11056095

RESUMO

BACKGROUND: In patients with chronic heart failure (CHF), periodic breathing (PB) predicts poor prognosis. Clinical studies have identified numerous risk factors for PB (which also includes Cheyne-Stokes respiration). Computer simulations have shown that oscillations can arise from delayed negative feedback. However, no simple general theory quantitatively explains PB and its mechanisms of treatment using widely-understood clinical concepts. Therefore, we introduce a new approach to the quantitative analysis of the dynamic physiology governing cardiorespiratory stability in CHF. METHODS AND RESULTS: An algebraic formula was derived (presented as a simple 2D plot), enabling prediction from easily acquired clinical data to determine whether respiration will be unstable. Clinical validation was performed in 20 patients with CHF (10 with PB and 10 without) and 10 healthy normal subjects. Measurements, including chemoreflex sensitivity (S) and delay (delta), alveolar volume (V(L)), and end-tidal CO(2) fraction (C), were applied to the stability formula. The breathing pattern was correctly predicted in 28 of the 30 subjects. The principal combined parameter (CS)x(delta/V(L)) was higher in patients with PB (14.2+/-3.0) than in those without PB (3.1+/-0.5; P:=0.0005) or in normal controls (2.4+/-0.5; P:=0.0003). This was because of differences in both chemoreflex sensitivity (1749+/-235 versus 620+/-103 and 526+/-104 L/min per atm CO(2); P:=0.0001 and P:<0.0001, respectively) and chemoreflex delay (0.53+/-0.06 vs 0.40+/-0.06 and 0.30+/-0.04 min; P:=NS and P:=0.02). CONCLUSION: This analytical approach identifies the physiological abnormalities that are important in the genesis of PB and explicitly defines the region of predicted instability. The clinical data identify chemoreflex gain and delay time (rather than hyperventilation or hypocapnia) as causes of PB.


Assuntos
Respiração de Cheyne-Stokes/fisiopatologia , Insuficiência Cardíaca/fisiopatologia , Modelos Cardiovasculares , Respiração , Respiração de Cheyne-Stokes/complicações , Doença Crônica , Insuficiência Cardíaca/complicações , Humanos , Matemática , Pessoa de Meia-Idade , Periodicidade , Pletismografia de Impedância , Valor Preditivo dos Testes , Troca Gasosa Pulmonar , Volume de Ventilação Pulmonar
10.
Circulation ; 100(21): 2198-203, 1999 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-10571980

RESUMO

BACKGROUND: Perioperative management of patients with complete mixing of pulmonary and systemic blood centers on approximately equating pulmonary (Qp) and systemic (Qs) blood flow (Qp/Qs approximately 1). This empirically derived target is opposed by theoretical studies advocating a target Qp/Qs well below 1. We studied the cause of this persistent discrepancy. METHODS AND RESULTS: Classic theoretical studies have concentrated on maximizing 1 of many potential combination parameters of arterial oxygen content (CaO(2)) and systemic blood flow: total oxygen delivery (DO(2))=CaO(2)xQs. We defined "useful" oxygen delivery as the amount of oxygen above a notional saturation threshold (Sat(Thresh)): D(u)O(2)=carrying capacityx(SaO(2)-Sat(Thresh))xQs. Whereas DO(2) peaks at Qp/Qs ratios <1, D(u)O(2) peaks at higher Qp/Qs ratios, nearer to (or exceeding) 1. Systemic venous saturation (which mirrors tissue oxygen tension) peaks at Qp/Qs=1. CONCLUSIONS: First, the standard model of single-ventricle physiology can be reexpressed in a form allowing analysis by differential calculus, which allows broader conclusions to be drawn than does computer modeling alone. Second, the classic measure DO(2) fails to reflect the fact that proportional changes in saturation and flow are not clinically equivalent. Recognizing this asymmetry by using D(u)O(2) can give a target Qp:Qs balance that better represents clinical experience. Finally, to avoid an arbitrary choice of Sat(Thresh), systemic venous oxygen saturation (SsvO(2)) may be a useful parameter to maximize: this occurs at a Qp/Qs ratio of 1. Attempts to increase DO(2) by altering Qp/Qs away from this value will inevitably reduce SsvO(2) and therefore tissue oxygenation. Oxygen delivery is far from synonymous with tissue oxygen status.


Assuntos
Circulação Coronária , Oxigênio/sangue , Circulação Pulmonar , Simulação por Computador , Humanos , Consumo de Oxigênio
11.
Circulation ; 100(10): 1065-70, 1999 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-10477531

RESUMO

BACKGROUND: Respiratory gas exchange measurements in patients with chronic heart failure (CHF) at rest and during exercise commonly reveal prominent slow oscillations in ventilation (V(E)), measured oxygen uptake (VO(2)), and carbon dioxide production (VCO(2)), whose origin is not clear. Voluntary simulation of periodic breathing (PB) in normals has been reported to generate a different pattern of oscillations in gas exchange from that seen in spontaneous PB. This necessitates hypothesizing that PB is caused by a primary oscillation in tissue metabolism or in cardiac output. METHODS AND RESULTS: We developed an automated method by which normal controls could be guided to breathe according to a PB pattern. The resultant metabolic oscillations closely matched those seen in spontaneous PB and had several interesting properties. At low workloads (including rest), the oscillations in VO(2) were as prominent as those in V(E) in both spontaneous PB (alpha(VO2)/alpha(VE)=0.92+/-0.04) and voluntary PB (0.93+/-0.07). However, at increased workload, the oscillations in VO(2) because less prominent than those in V(E) in spontaneous PB (intermediate workload 0.63+/-0.05, high workload 0.57+/-0.04; P<0.001) and voluntary PB (intermediate 0.66+/-0.03, high 0.48+/-0.03; P<0.001). There was no difference in the relative size of metabolic oscillations between voluntary and spontaneous PB at matched workloads (P>0.05 at low, intermediate, and high workloads). Furthermore, VO(2) peaked before V(E) in both spontaneous and voluntary PB. This time delay varied from 6.4+/-0.4 s at low ventilation, to 11.3+/-0.9 s at high ventilation (P<0.0001). CONCLUSIONS: The magnitude and phase pattern of oscillations in gas exchange of spontaneous PB can be obtained by adequately matched voluntary PB. Therefore, the gas exchange features of PB are explicable by primary ventilatory oscillation.


Assuntos
Baixo Débito Cardíaco/fisiopatologia , Troca Gasosa Pulmonar , Adulto , Idoso , Dióxido de Carbono/metabolismo , Doença Crônica , Humanos , Cinética , Pessoa de Meia-Idade , Oscilometria , Consumo de Oxigênio , Fatores de Tempo
12.
Circulation ; 108(1): 54-9, 2003 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-12821550

RESUMO

BACKGROUND: Heart failure treatment depends partly on the underlying cause of the disease. We evaluated cardiovascular magnetic resonance (CMR) for the problem of differentiating dilated cardiomyopathy (DCM) from left ventricular (LV) dysfunction caused by coronary artery disease (CAD). METHODS AND RESULTS: Late gadolinium enhancement with CMR was performed in 90 patients with heart failure and LV systolic dysfunction (63 patients with DCM and unobstructed coronary arteries and 27 with significant CAD at angiography). We also studied 15 control subjects with no coronary risk factors and/or unobstructed coronary arteries. None (0%) of the control subjects had myocardial gadolinium enhancement; however, all patients (100%) with LV dysfunction and CAD had enhancement, which was subendocardial or transmural. In patients with DCM, there were 3 findings: no enhancement (59%); myocardial enhancement indistinguishable from the patients with CAD (13%); and patchy or longitudinal striae of midwall enhancement clearly different from the distribution in patients with CAD (28%). CONCLUSIONS: Gadolinium CMR is a powerful technique to distinguish DCM from LV dysfunction related to CAD and yields new insights in DCM. These data suggest that using the coronary angiogram as the arbiter for the presence of LV dysfunction caused by CAD could have lead to an incorrect assignment of DCM cause in 13% of patients, possibly because of coronary recanalization after infarction. The midwall myocardial enhancement in patients with DCM is similar to the fibrosis found at autopsy; it has not previously been visualized in vivo and warrants further investigation. CMR may become a useful alternative to routine coronary angiography in the diagnostic workup of DCM.


Assuntos
Cardiomiopatia Dilatada/diagnóstico , Doença da Artéria Coronariana/diagnóstico , Gadolínio , Insuficiência Cardíaca/diagnóstico , Imageamento por Ressonância Magnética , Idoso , Cardiomiopatia Dilatada/complicações , Doença Crônica , Doença da Artéria Coronariana/complicações , Diagnóstico Diferencial , Feminino , Insuficiência Cardíaca/etiologia , Humanos , Aumento da Imagem , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Valores de Referência , Fatores de Risco , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Esquerda/etiologia
13.
Circulation ; 100(24): 2418-24, 1999 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-10595954

RESUMO

BACKGROUND: Oscillatory breathing patterns characterized by rises and falls in ventilation with apnea (Cheyne-Stokes respiration [CSR]) or without apnea (periodic breathing [PB]) commonly occur during the daytime in chronic heart failure (CHF). We have prospectively characterized patients with cyclical breathing in terms of clinical characteristics, indices of autonomic control, prognosis, and the role of peripheral chemosensitivity. METHODS AND RESULTS: To determine cyclical breathing pattern, power spectral analysis was applied to 30-minute recordings of respiration in 74 stable CHF patients. Analyses of heart rate variability and baroreflex sensitivity were used to assess autonomic balance. Peripheral chemosensitivity was assessed with the transient hypoxia method. We also determined whether the suppression of peripheral chemoreceptor activity (hyperoxia or dihydrocodeine) would influence the respiratory pattern. Cyclical respiration was found in 49 (66%) patients (22 [30%] CSR, 27 [36%] PB) and was associated with more advanced CHF symptoms, impaired autonomic balance, and increased chemosensitivity (0.80 and 0.75 versus 0.34 L. min(-1). %SaO(2)(-1), P<0.001, for CSR and PB versus normal breathing, respectively). Transient hyperoxia abolished oscillatory breathing in 7 of 8 patients. Dihydrocodeine administration decreased chemosensitivity by 42% (P=0.05), which correlated with improvement in respiratory pattern. Cyclical breathing predicted poor 2-year survival (relative risk 9.41, P<0.01, by Cox proportional hazards analysis), independent of peak oxygen consumption (P=0.04). CONCLUSIONS: An oscillatory breathing pattern during the daytime is a marker of impaired autonomic regulation and poor outcome. Augmented activity of peripheral chemoreceptors may be involved in the genesis of this respiratory pattern. Modulation of peripheral chemosensitivity can reduce or abolish abnormal respiratory patterns and may be an option in the management of CHF patients with oscillatory breathing.


Assuntos
Respiração de Cheyne-Stokes/fisiopatologia , Insuficiência Cardíaca/fisiopatologia , Pressorreceptores/fisiologia , Idoso , Analgésicos Opioides/administração & dosagem , Sistema Nervoso Autônomo/fisiologia , Doença Crônica , Codeína/administração & dosagem , Codeína/análogos & derivados , Feminino , Seguimentos , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Oxigênio/administração & dosagem , Consumo de Oxigênio , Periodicidade , Equilíbrio Postural , Pressorreceptores/efeitos dos fármacos , Prognóstico , Estudos Prospectivos , Mecânica Respiratória/efeitos dos fármacos , Mecânica Respiratória/fisiologia , Vigília
14.
Circulation ; 102(25): 3060-7, 2000 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-11120695

RESUMO

BACKGROUND: Inflammatory immune activation is an important feature in chronic heart failure (CHF). Little is known about the prognostic importance of tumor necrosis factor-alpha (TNF-alpha), soluble TNF-receptor 1 and 2 (sTNF-R1/sTNF-R2), interleukin-6 (IL-6), and soluble CD14 receptors (sCD14) in CHF patients. METHODS AND RESULTS: In 152 CHF patients (age 61+/-1 years, New York Heart Association [NYHA] class 2.6+/-0.1, peak VO(2) 17.3+/-0.6 mL. kg(-1). min(-1), mean+/-SEM) plasma concentrations of immune variables were prospectively assessed. During a mean follow-up of 34 months (>12 months in all patients), 62 patients (41%) died. Cumulative mortality was 28% at 24 months. In univariate analyses, increased total and trimeric TNF-alpha, sTNF-R1, and sTNF-R2 (all P

Assuntos
Baixo Débito Cardíaco/imunologia , Baixo Débito Cardíaco/mortalidade , Citocinas/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Antígenos CD/sangue , Biomarcadores/sangue , Baixo Débito Cardíaco/sangue , Doença Crônica , Feminino , Humanos , Imunoensaio , Interleucina-6/sangue , Receptores de Lipopolissacarídeos/sangue , Masculino , Pessoa de Meia-Idade , Prognóstico , Curva ROC , Receptores do Fator de Necrose Tumoral/sangue , Receptores Tipo I de Fatores de Necrose Tumoral , Receptores Tipo II do Fator de Necrose Tumoral , Solubilidade , Análise de Sobrevida , Fator de Necrose Tumoral alfa/metabolismo
15.
Circulation ; 104(5): 544-9, 2001 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-11479251

RESUMO

BACKGROUND: Peripheral chemoreceptor hypersensitivity is a feature of abnormal cardiorespiratory reflex control in chronic heart failure (CHF) and may contribute to sympathetic overactivity, attenuated baroreflex sensitivity (BRS), and excessive ventilation during exercise. We studied whether augmented peripheral chemosensitivity carries independent prognostic significance. METHODS AND RESULTS: We assessed peripheral chemosensitivity (ventilatory response to hypoxia using transient inhalation of pure nitrogen) and BRS (phenylephrine and spectral methods) in 80 consecutive CHF patients (age 58+/-9 years; left ventricular ejection fraction [LVEF] 24+/-12%; peak oxygen consumption [peak VO(2)] 18+/-7 mL(-1). min(-1)). CHF patients demonstrated augmented peripheral chemosensitivity and decreased BRS (all P<0.01 versus reference values). During follow-up (median 41 months, >3 years in all survivors), 37 patients died. High peripheral chemosensitivity (>0.72 L. min(-1). %SaO(2)(-1)) predicted impaired survival (hazard ratio 3.2, 95% CI 1.6 to 6.0, P=0.0006). In the 27 patients (34%) with high peripheral chemosensitivity, 3-year survival was 41% (95% CI 22% to 60%) compared with 77% (66% to 89%) in 53 patients with normal chemosensitivity (P=0.0002). In multivariate analyses, augmented chemosensitivity independently predicted death (hazard ratio 2.8, 95% CI 1.5 to 5.5, adjusted for age, peak VO(2), and VE/VCO(2) [P=0.002]; hazard ratio 2.6, 95% CI 1.3 to 5.1, adjusted for age, LVEF, and peak VO(2) [P=0.008]). Depressed BRS was related to unfavorable prognosis in univariate analysis (P=0.05) but not in multivariate analyses. CONCLUSIONS: Hypersensitivity of the peripheral chemoreceptors independently predicts adverse prognosis in ambulatory patients with CHF. This hyperactive excitatory reflex, through its inhibitory effect on the baroreflex, may be the reason for the previously observed prognostic association of the latter.


Assuntos
Células Quimiorreceptoras/fisiopatologia , Insuficiência Cardíaca/fisiopatologia , Idoso , Pressão Sanguínea/fisiologia , Doença Crônica , Teste de Esforço , Feminino , Seguimentos , Insuficiência Cardíaca/mortalidade , Frequência Cardíaca/fisiologia , Humanos , Hipóxia/fisiopatologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Consumo de Oxigênio , Prognóstico , Análise de Sobrevida , Taxa de Sobrevida
16.
Circulation ; 103(7): 967-72, 2001 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-11181471

RESUMO

BACKGROUND: In patients with chronic heart failure (CHF) and preserved exercise tolerance, the value of cardiopulmonary exercise testing for risk stratification is not known. Elevated slope of ventilatory response to exercise (VE/VCO(2)) predicts poor prognosis in advanced CHF. Derangement of cardiopulmonary reflexes may trigger exercise hyperpnea. We assessed the relationship between cardiopulmonary reflexes and VE/VCO(2)and investigated the prognostic value of (VE/VCO(2)) in CHF patients with preserved exercise tolerance. METHODS AND RESULTS: Among 344 consecutive CHF patients, we identified 123 with preserved exercise capacity, defined as a peak oxygen consumption (PEAK VO(2)) >/=18 mL. kg(-1). min(-1) (age 56 years; left ventricular ejection fraction 28%; peak VO(2) 23.5 mL. kg(-1). min(-1)). Hypoxic and hypercapnic chemosensitivity (n=38), heart rate variability (n=34), baroreflex sensitivity (n=20), and ergoreflex activity (n=20) were also assessed. We identified 40 patients (33%) with high VE/VCO(2) (ie, >34.0). During follow-up (49+/-22 months, >3 years in all survivors), 34 patients died (3-year survival 81%). High VE/VCO(2) (hazard ratio 4.3, P<0.0001) but not peak f1.gif" BORDER="0">O(2) (P=0.7) predicted mortality. In patients with high VE/VCO(2), 3-year survival was 57%, compared with 93% in patients with normal VE/VCO(2) P<0.0001). Patients with high VE/VCO(2) demonstrated impaired reflex control, as evidenced by augmented peripheral (P=0.01) and central (P=0.0006) chemosensitivity, depressed low-frequency component of heart rate variability (P<0.0001) and baroreflex sensitivity (P=0.03), and overactive ergoreceptors (P=0.003) compared with patients with normal VE/VCO(2). CONCLUSIONS: In CHF patients with preserved exercise capacity, enhanced ventilatory response to exercise is a simple marker of a widespread derangement of cardiovascular reflex control; it predicts poor prognosis, which VO(2) does not.


Assuntos
Tolerância ao Exercício , Insuficiência Cardíaca/fisiopatologia , Testes de Função Respiratória/estatística & dados numéricos , Ventilação/estatística & dados numéricos , Doença Crônica , Teste de Esforço/estatística & dados numéricos , Seguimentos , Insuficiência Cardíaca/diagnóstico , Testes de Função Cardíaca/estatística & dados numéricos , Humanos , Pessoa de Meia-Idade , Análise Multivariada , Consumo de Oxigênio , Valor Preditivo dos Testes , Prognóstico , Modelos de Riscos Proporcionais , Medição de Risco , Taxa de Sobrevida
17.
Cell Death Differ ; 11(5): 527-41, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-14765134

RESUMO

The majority of ovarian cancer cells are resistant to apoptosis induced by tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). Subtoxic concentrations of the semisynthetic retinoid N-(4-hydroxyphenyl)retinamide (4HPR) enhanced TRAIL-mediated apoptosis in ovarian cancer cell lines but not in immortalized nontumorigenic ovarian epithelial cells. The enhancement of TRAIL-mediated apoptosis by 4HPR was not due to changes in the levels of proteins known to modulate TRAIL sensitivity. The combination of 4HPR and TRAIL enhanced cleavage of multiple caspases in the death receptor pathway (including the two initiator caspases, caspase-8 and caspase-9). The 4HPR and TRAIL combination leads to mitochondrial permeability transition, significant increase in cytochrome c release, and increased caspase-9 activation. Caspase-9 may further activate caspase-8, generating an amplification loop. Stable overexpression of Bcl-xL abrogates the interaction between 4HPR and TRAIL at the mitochondrial level by blocking cytochrome c release. As a consequence, a decrease in activation of caspase-9, caspase-8, and TRAIL-mediated apoptosis occurs. These results indicate that the enhancement in TRAIL-mediated apoptosis induced by 4HPR is due to the increase in activation of multiple caspases involving an amplification loop via the mitochondrial-death pathway. These findings offer a promising and novel strategy for the treatment of ovarian cancer.


Assuntos
Apoptose/efeitos dos fármacos , Fenretinida/toxicidade , Glicoproteínas de Membrana/metabolismo , Mitocôndrias/metabolismo , Receptores X de Retinoides/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Apoptose/fisiologia , Proteínas Reguladoras de Apoptose , Caspases/metabolismo , Citocromos c/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Feminino , Humanos , Ovário/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF , Células Tumorais Cultivadas
18.
Lancet ; 362(9377): 14-21, 2003 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-12853194

RESUMO

BACKGROUND: The improvement in left-ventricular ejection fraction (LVEF) in response to beta blockers is heterogeneous in patients with heart failure due to ischaemic heart disease, possibly indicating variations in the myocardial substrate underlying left-ventricular dysfunction. We investigated whether improvement in LVEF was associated with the volume of hibernating myocardium (viable myocardium with contractile failure). METHODS: We did a double-blind, randomised trial to compare placebo and carvedilol for 6 months in individuals with stable, chronic heart failure due to ischaemic left-ventricular systolic dysfunction. We enrolled 489 patients, of whom 387 were randomised. Patients were designated hibernators or non-hibernators according to the volume of hibernating myocardium. The primary endpoint was change in LVEF, measured by radionuclide ventriculography, in hibernators versus non-hibernators, on carvedilol compared with placebo. Analysis was by intention to treat. RESULTS: 82 patients dropped out of the study because of adverse events, withdrawal of consent, or failure to complete the investigation. Thus, 305 (79%) were analysed. LVEF was unchanged with placebo (mean change -0.4 [SE 0.9] and -0.4 [0.8] for non-hibernators and hibernators, respectively) but increased with carvedilol (2.5 [0.9] and 3.2 [0.8], respectively; p<0.0001 compared with baseline). Mean placebo-subtracted change in LVEF was 3.2% (95% CI 1.8-4.7; p=0.0001) overall, and 2.9% (0.7-5.1; p=0.011) and 3.6% (1.7-5.4; p=0.0002) in non-hibernators and hibernators, respectively. Effect of hibernator status on response of LVEF to carvedilol was not significant (0.7 [-2.2 to 3.5]; p=0.644). However, patients with more myocardium affected by hibernation or by hibernation and ischaemia had a greater increase in LVEF on carvedilol (p=0.0002 and p=0.009, respectively). INTERPRETATION: Some of the effect of carvedilol on LVEF might be mediated by improved function of hibernating or ischaemic myocardium, or both. Medical treatment might be an important adjunct or alternative to revascularisation for patients with hibernating myocardium.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Carbazóis/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/fisiopatologia , Propanolaminas/uso terapêutico , Volume Sistólico/fisiologia , Disfunção Ventricular Esquerda/fisiopatologia , Carvedilol , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Miocárdio Atordoado/complicações , Disfunção Ventricular Esquerda/etiologia
19.
J Am Coll Cardiol ; 22(4 Suppl A): 172A-177A, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8376689

RESUMO

In acute heart failure with pulmonary edema, rest is a useful adjunct to pharmacologic treatment because it increases urinary flow and enhances the effectiveness of diuretic drugs. In chronic heart failure, however, there is increasing evidence that avoiding exercise can lead to deconditioning changes in skeletal muscle and in the peripheral circulation that may actually impair exercise tolerance. Exercise training was introduced as part of postinfarction rehabilitation in the 1960s, but it was not tested in patients with heart failure until well into the 1980s. Several reports have now shown considerable improvements in exercise capacity after physical training in patients with stable chronic nonedematous heart failure. Many of the peripheral abnormalities described in chronic heart failure have been shown to be at least partially reversible after physical training. These include abnormalities of skeletal muscle, respiratory gas exchange and autonomic nervous control of the circulation. Controversy still exists as to whether training may have beneficial prognostic effects in chronic heart failure and how soon after myocardial infarction it is safe to commence training. In addition, little information exists as to the most appropriate form of exercise therapy and the proper criteria for patient selection into training programs. Exercise training seems set to become a popular and beneficial adjunct to the management of patients with chronic heart failure. It has been shown to have a beneficial effect on symptoms, exercise performance and a host of pathophysiologic changes characteristic of chronic heart failure. Whether it improves prognosis is not known.


Assuntos
Terapia por Exercício , Insuficiência Cardíaca/reabilitação , Sistema Cardiovascular/fisiopatologia , Doença Crônica , Terapia por Exercício/métodos , Tolerância ao Exercício , Insuficiência Cardíaca/fisiopatologia , Humanos , Sistema Musculoesquelético/fisiopatologia , Função Ventricular Esquerda
20.
J Am Coll Cardiol ; 30(7): 1827-34, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9385914

RESUMO

OBJECTIVES: We sought to compare the arterial blood gas chemosensitivity in relation to exercise ventilatory response in patients with univentricular heart and cyanosis and in patients with univentricular heart and Fontan-type circulation without cyanosis. BACKGROUND: Patients with univentricular heart demonstrate excessive ventilation during exercise. Chronic hypoxemia may alter chemoreceptor function, affecting ventilation. METHODS: Cardiopulmonary exercise testing was performed in 10 patients with rest or stress-induced cyanosis (cyanotic group: mean age +/- SE 30.5 +/- 2.3 years; 5 men), 8 patients without cyanosis with Fontan-type circulation (Fontan group: mean age 29.4 +/- 1.5 years; 4 men) and 10 healthy control subjects (normal group: mean age 30.7 +/- 1.9 years; 5 men). Hypoxic and hypercapnic chemosensitivity were assessed by using transient inhalations of pure nitrogen and the rebreathing of 7% CO2 in 93% O2, respectively. RESULTS: Peak O2 consumption was comparable in both patient groups (21.7 +/- 2.5 [cyanotic group] vs. 21.0 +/- 1.9 ml/kg per min [Fontan group]) but was lower than that in the normal group (34.7 +/- 1.9 ml/kg per min). The ventilatory response to exercise, characterized by the regression slope relating minute ventilation to CO2 output, was higher in the cyanotic group (43.4 +/- 4.0) than in the Fontan group (31.4 +/- 3.0, p = 0.02) and the normal group (23.1 +/- 1.1). Hypoxic chemosensitivity was blunted in the cyanotic group compared with that in the Fontan and normal groups (0.148 vs. 0.448 [p = 0.02] vs. 0.311 liter/min per percent arterial O2 saturation, respectively) and did not correlate with the ventilatory response to exercise (r = -0.36, p = 0.29). In contrast, hypercapnic chemosensitivity represented by the slope of the hypercapnic-ventilatory response line was similar in the cyanotic, Fontan and normal groups (1.71 vs. 1.76 vs. 1.70 liter/min per mm Hg, respectively), but the response line had shifted to the left in the cyanotic group (x intercept = 31.9 vs. 39.9 mm Hg [p = 0.026]), compared with 45.2 mm Hg in normal subjects. These findings suggest that in the cyanotic group, ventilation is greater for a given level of arterial CO2 tension and thus may partly explain the increased exercise ventilatory response in this group. CONCLUSIONS: Hypoxic chemosensitivity is blunted in patients with univentricular heart and cyanosis and does not determine the exercise ventilatory response. CO2 elimination appears more important. The blunting of hypoxic chemosensitivity is reversible once chronic hypoxemia is relieved, as evident in the Fontan group.


Assuntos
Células Quimiorreceptoras/fisiologia , Cardiopatias Congênitas/sangue , Hipóxia/fisiopatologia , Ventilação Pulmonar/fisiologia , Adulto , Dióxido de Carbono/farmacologia , Estudos de Casos e Controles , Células Quimiorreceptoras/efeitos dos fármacos , Teste de Esforço , Tolerância ao Exercício/fisiologia , Feminino , Técnica de Fontan , Cardiopatias Congênitas/fisiopatologia , Cardiopatias Congênitas/cirurgia , Humanos , Masculino , Consumo de Oxigênio/fisiologia
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