Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 92
Filtrar
1.
N Engl J Med ; 373(24): 2314-24, 2015 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-26549714

RESUMO

BACKGROUND: Nitrates are commonly prescribed to enhance activity tolerance in patients with heart failure and a preserved ejection fraction. We compared the effect of isosorbide mononitrate or placebo on daily activity in such patients. METHODS: In this multicenter, double-blind, crossover study, 110 patients with heart failure and a preserved ejection fraction were randomly assigned to a 6-week dose-escalation regimen of isosorbide mononitrate (from 30 mg to 60 mg to 120 mg once daily) or placebo, with subsequent crossover to the other group for 6 weeks. The primary end point was the daily activity level, quantified as the average daily accelerometer units during the 120-mg phase, as assessed by patient-worn accelerometers. Secondary end points included hours of activity per day during the 120-mg phase, daily accelerometer units during all three dose regimens, quality-of-life scores, 6-minute walk distance, and levels of N-terminal pro-brain natriuretic peptide (NT-proBNP). RESULTS: In the group receiving the 120-mg dose of isosorbide mononitrate, as compared with the placebo group, there was a nonsignificant trend toward lower daily activity (-381 accelerometer units; 95% confidence interval [CI], -780 to 17; P=0.06) and a significant decrease in hours of activity per day (-0.30 hours; 95% CI, -0.55 to -0.05; P=0.02). During all dose regimens, activity in the isosorbide mononitrate group was lower than that in the placebo group (-439 accelerometer units; 95% CI, -792 to -86; P=0.02). Activity levels decreased progressively and significantly with increased doses of isosorbide mononitrate (but not placebo). There were no significant between-group differences in the 6-minute walk distance, quality-of-life scores, or NT-proBNP levels. CONCLUSIONS: Patients with heart failure and a preserved ejection fraction who received isosorbide mononitrate were less active and did not have better quality of life or submaximal exercise capacity than did patients who received placebo. (Funded by the National Heart, Lung, and Blood Institute; ClinicalTrials.gov number, NCT02053493.).


Assuntos
Insuficiência Cardíaca/tratamento farmacológico , Dinitrato de Isossorbida/análogos & derivados , Vasodilatadores/uso terapêutico , Acelerometria , Idoso , Estudos Cross-Over , Método Duplo-Cego , Tolerância ao Exercício , Feminino , Insuficiência Cardíaca/fisiopatologia , Humanos , Dinitrato de Isossorbida/efeitos adversos , Dinitrato de Isossorbida/uso terapêutico , Masculino , Pessoa de Meia-Idade , Atividade Motora , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Qualidade de Vida , Volume Sistólico , Vasodilatadores/efeitos adversos , Caminhada
2.
JAMA ; 317(19): 1958-1966, 2017 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-28510680

RESUMO

IMPORTANCE: Iron deficiency is present in approximately 50% of patients with heart failure with reduced left ventricular ejection fraction (HFrEF) and is an independent predictor of reduced functional capacity and mortality. However, the efficacy of inexpensive readily available oral iron supplementation in heart failure is unknown. OBJECTIVE: To test whether therapy with oral iron improves peak exercise capacity in patients with HFrEF and iron deficiency. DESIGN, SETTING, AND PARTICIPANTS: Phase 2, double-blind, placebo-controlled randomized clinical trial of patients with HFrEF (<40%) and iron deficiency, defined as a serum ferritin level of 15 to 100 ng/mL or a serum ferritin level of 101 to 299 ng/mL with transferrin saturation of less than 20%. Participants were enrolled between September 2014 and November 2015 at 23 US sites. INTERVENTIONS: Oral iron polysaccharide (n = 111) or placebo (n = 114), 150 mg twice daily for 16 weeks. MAIN OUTCOMES AND MEASURES: The primary end point was a change in peak oxygen uptake (V̇o2) from baseline to 16 weeks. Secondary end points were change in 6-minute walk distance, plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels, and health status as assessed by Kansas City Cardiomyopathy Questionnaire (KCCQ, range 0-100, higher scores reflect better quality of life). RESULTS: Among 225 randomized participants (median age, 63 years; 36% women) 203 completed the study. The median baseline peak V̇o2 was 1196 mL/min (interquartile range [IQR], 887-1448 mL/min) in the oral iron group and 1167 mL/min (IQR, 887-1449 mL/min) in the placebo group. The primary end point, change in peak V̇o2 at 16 weeks, did not significantly differ between the oral iron and placebo groups (+23 mL/min vs -2 mL/min; difference, 21 mL/min [95% CI, -34 to +76 mL/min]; P = .46). Similarly, at 16 weeks, there were no significant differences between treatment groups in changes in 6-minute walk distance (-13 m; 95% CI, -32 to 6 m), NT-proBNP levels (159; 95% CI, -280 to 599 pg/mL), or KCCQ score (1; 95% CI, -2.4 to 4.4), all P > .05. CONCLUSIONS AND RELEVANCE: Among participants with HFrEF with iron deficiency, high-dose oral iron did not improve exercise capacity over 16 weeks. These results do not support use of oral iron supplementation in patients with HFrEF. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT02188784.


Assuntos
Tolerância ao Exercício , Ferritinas/sangue , Insuficiência Cardíaca/fisiopatologia , Compostos de Ferro/administração & dosagem , Deficiências de Ferro , Consumo de Oxigênio , Volume Sistólico/fisiologia , Administração Oral , Idoso , Método Duplo-Cego , Feminino , Nível de Saúde , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/metabolismo , Humanos , Compostos de Ferro/efeitos adversos , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Qualidade de Vida , Fatores de Tempo , Transferrina/metabolismo , Resultado do Tratamento , Teste de Caminhada
3.
Circulation ; 131(20): 1763-71, 2015 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-25986447

RESUMO

BACKGROUND: Oxidative stress may contribute to heart failure (HF) progression. Inhibiting xanthine oxidase in hyperuricemic HF patients may improve outcomes. METHODS AND RESULTS: We randomly assigned 253 patients with symptomatic HF, left ventricular ejection fraction ≤40%, and serum uric acid levels ≥9.5 mg/dL to receive allopurinol (target dose, 600 mg daily) or placebo in a double-blind, multicenter trial. The primary composite end point at 24 weeks was based on survival, worsening HF, and patient global assessment. Secondary end points included change in quality of life, submaximal exercise capacity, and left ventricular ejection fraction. Uric acid levels were significantly reduced with allopurinol in comparison with placebo (treatment difference, -4.2 [-4.9, -3.5] mg/dL and -3.5 [-4.2, -2.7] mg/dL at 12 and 24 weeks, respectively, both P<0.0001). At 24 weeks, there was no significant difference in clinical status between the allopurinol- and placebo-treated patients (worsened 45% versus 46%, unchanged 42% versus 34%, improved 13% versus 19%, respectively; P=0.68). At 12 and 24 weeks, there was no significant difference in change in Kansas City Cardiomyopathy Questionnaire scores or 6-minute walk distances between the 2 groups. At 24 weeks, left ventricular ejection fraction did not change in either group or between groups. Rash occurred more frequently with allopurinol (10% versus 2%, P=0.01), but there was no difference in serious adverse event rates between the groups (20% versus 15%, P=0.36). CONCLUSIONS: In high-risk HF patients with reduced ejection fraction and elevated uric acid levels, xanthine oxidase inhibition with allopurinol failed to improve clinical status, exercise capacity, quality of life, or left ventricular ejection fraction at 24 weeks. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00987415.


Assuntos
Alopurinol/uso terapêutico , Insuficiência Cardíaca/complicações , Hiperuricemia/tratamento farmacológico , Xantina Oxidase/antagonistas & inibidores , Idoso , Alopurinol/efeitos adversos , Biomarcadores/sangue , Diuréticos/uso terapêutico , Método Duplo-Cego , Determinação de Ponto Final , Teste de Esforço , Tolerância ao Exercício , Feminino , Gota/tratamento farmacológico , Supressores da Gota/uso terapêutico , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/diagnóstico por imagem , Hospitalização/estatística & dados numéricos , Humanos , Hiperuricemia/complicações , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo , Qualidade de Vida , Volume Sistólico , Inquéritos e Questionários , Resultado do Tratamento , Ultrassonografia
4.
N Engl J Med ; 367(24): 2296-304, 2012 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-23131078

RESUMO

BACKGROUND: Ultrafiltration is an alternative strategy to diuretic therapy for the treatment of patients with acute decompensated heart failure. Little is known about the efficacy and safety of ultrafiltration in patients with acute decompensated heart failure complicated by persistent congestion and worsened renal function. METHODS: We randomly assigned a total of 188 patients with acute decompensated heart failure, worsened renal function, and persistent congestion to a strategy of stepped pharmacologic therapy (94 patients) or ultrafiltration (94 patients). The primary end point was the bivariate change from baseline in the serum creatinine level and body weight, as assessed 96 hours after random assignment. Patients were followed for 60 days. RESULTS: Ultrafiltration was inferior to pharmacologic therapy with respect to the bivariate end point of the change in the serum creatinine level and body weight 96 hours after enrollment (P=0.003), owing primarily to an increase in the creatinine level in the ultrafiltration group. At 96 hours, the mean change in the creatinine level was -0.04±0.53 mg per deciliter (-3.5±46.9 µmol per liter) in the pharmacologic-therapy group, as compared with +0.23±0.70 mg per deciliter (20.3±61.9 µmol per liter) in the ultrafiltration group (P=0.003). There was no significant difference in weight loss 96 hours after enrollment between patients in the pharmacologic-therapy group and those in the ultrafiltration group (a loss of 5.5±5.1 kg [12.1±11.3 lb] and 5.7±3.9 kg [12.6±8.5 lb], respectively; P=0.58). A higher percentage of patients in the ultrafiltration group than in the pharmacologic-therapy group had a serious adverse event (72% vs. 57%, P=0.03). CONCLUSIONS: In a randomized trial involving patients hospitalized for acute decompensated heart failure, worsened renal function, and persistent congestion, the use of a stepped pharmacologic-therapy algorithm was superior to a strategy of ultrafiltration for the preservation of renal function at 96 hours, with a similar amount of weight loss with the two approaches. Ultrafiltration was associated with a higher rate of adverse events. (Funded by the National Heart, Lung, and Blood Institute; ClinicalTrials.gov number, NCT00608491.).


Assuntos
Síndrome Cardiorrenal/terapia , Diuréticos/uso terapêutico , Insuficiência Cardíaca/terapia , Ultrafiltração , Idoso , Algoritmos , Síndrome Cardiorrenal/etiologia , Creatinina/sangue , Diuréticos/efeitos adversos , Feminino , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/mortalidade , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Ultrafiltração/efeitos adversos , Redução de Peso/efeitos dos fármacos
5.
Circulation ; 128(5): 502-11, 2013 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-23775260

RESUMO

BACKGROUND: Pulmonary hypertension caused by systolic left ventricular dysfunction is associated with significant morbidity and mortality; however, no treatment is approved for this indication. We hypothesized that riociguat, a novel soluble guanylate cyclase stimulator, would have beneficial hemodynamic effects in patients with pulmonary hypertension caused by systolic left ventricular dysfunction. METHODS AND RESULTS: Overall, 201 patients with heart failure resulting from pulmonary hypertension caused by systolic left ventricular dysfunction were randomized to double-blind treatment with oral placebo or riociguat (0.5, 1, or 2 mg 3 times daily) for 16 weeks in 4 parallel arms. The primary outcome was the placebo-corrected change from baseline at week 16 in mean pulmonary artery pressure. Although the decrease in mean pulmonary artery pressure in the riociguat 2 mg group (-6.1±1.3 mm Hg; P<0.0001 versus baseline) was not significantly different from placebo (P=0.10), cardiac index (0.4 L·min(-1)·m(-2); 95% confidence interval, 0.2-0.5; P=0.0001) and stroke volume index (5.2 mL·m(-2); 95% confidence interval, 2.0-8.4; P=0.0018) were significantly increased without changes in heart rate or systemic blood pressure compared with placebo. Both pulmonary (-46.6 dynes·s(-1)·cm(-5); 95% confidence interval, -89.4 to -3.8; P=0.03) and systemic vascular resistance (-239.3 dynes·s(-1)·cm(-5); 95% confidence interval, -363.4 to -115.3; P=0.0002) were significantly reduced with riociguat 2 mg. Riociguat reduced the Minnesota Living With Heart Failure score (P=0.0002). Discontinuation of treatment was similar between treatment groups. CONCLUSIONS: Although the primary end point of the study was not met, riociguat was well tolerated in patients with pulmonary hypertension caused by systolic left ventricular dysfunction and improved cardiac index and pulmonary and systemic vascular resistance. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01065454.


Assuntos
Hemodinâmica/efeitos dos fármacos , Hipertensão Pulmonar/tratamento farmacológico , Hipertensão Pulmonar/epidemiologia , Pirazóis/uso terapêutico , Pirimidinas/uso terapêutico , Disfunção Ventricular Esquerda/tratamento farmacológico , Disfunção Ventricular Esquerda/epidemiologia , Adulto , Idoso , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade
6.
N Engl J Med ; 364(9): 797-805, 2011 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-21366472

RESUMO

BACKGROUND: Loop diuretics are an essential component of therapy for patients with acute decompensated heart failure, but there are few prospective data to guide their use. METHODS: In a prospective, double-blind, randomized trial, we assigned 308 patients with acute decompensated heart failure to receive furosemide administered intravenously by means of either a bolus every 12 hours or continuous infusion and at either a low dose (equivalent to the patient's previous oral dose) or a high dose (2.5 times the previous oral dose). The protocol allowed specified dose adjustments after 48 hours. The coprimary end points were patients' global assessment of symptoms, quantified as the area under the curve (AUC) of the score on a visual-analogue scale over the course of 72 hours, and the change in the serum creatinine level from baseline to 72 hours. RESULTS: In the comparison of bolus with continuous infusion, there was no significant difference in patients' global assessment of symptoms (mean AUC, 4236±1440 and 4373±1404, respectively; P=0.47) or in the mean change in the creatinine level (0.05±0.3 mg per deciliter [4.4±26.5 µmol per liter] and 0.07±0.3 mg per deciliter [6.2±26.5 µmol per liter], respectively; P=0.45). In the comparison of the high-dose strategy with the low-dose strategy, there was a nonsignificant trend toward greater improvement in patients' global assessment of symptoms in the high-dose group (mean AUC, 4430±1401 vs. 4171±1436; P=0.06). There was no significant difference between these groups in the mean change in the creatinine level (0.08±0.3 mg per deciliter [7.1±26.5 µmol per liter] with the high-dose strategy and 0.04±0.3 mg per deciliter [3.5±26.5 µmol per liter] with the low-dose strategy, P=0.21). The high-dose strategy was associated with greater diuresis and more favorable outcomes in some secondary measures but also with transient worsening of renal function. CONCLUSIONS: Among patients with acute decompensated heart failure, there were no significant differences in patients' global assessment of symptoms or in the change in renal function when diuretic therapy was administered by bolus as compared with continuous infusion or at a high dose as compared with a low dose. (Funded by the National Heart, Lung, and Blood Institute; ClinicalTrials.gov number, NCT00577135.).


Assuntos
Diuréticos/administração & dosagem , Furosemida/administração & dosagem , Insuficiência Cardíaca/tratamento farmacológico , Inibidores de Simportadores de Cloreto de Sódio e Potássio/administração & dosagem , Doença Aguda , Idoso , Área Sob a Curva , Creatinina/sangue , Diuréticos/efeitos adversos , Método Duplo-Cego , Esquema de Medicação , Dispneia/etiologia , Feminino , Furosemida/efeitos adversos , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/complicações , Humanos , Infusões Intravenosas , Injeções Intravenosas , Análise de Intenção de Tratamento , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Inibidores de Simportadores de Cloreto de Sódio e Potássio/efeitos adversos
7.
Eur Heart J ; 34(1): 57-67, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22778174

RESUMO

AIMS: Cinaciguat (BAY 58-2667) is a novel soluble guanylate cyclase activator. This study evaluated the haemodynamic effect and safety of cinaciguat added to standard therapy in patients with acute decompensated heart failure (ADHF). METHODS AND RESULTS: In this placebo-controlled, phase IIb study (NCT00559650), 139 patients admitted with ADHF, pulmonary capillary wedge pressure (PCWP) ≥18 mmHg, left ventricular ejection fraction <40%, and a pre-existing need for invasive haemodynamic monitoring were randomized 2:1 to cinaciguat:placebo (continuous i.v. infusion). The dose was titrated for 8 h and maintained for 16-40 h (starting dose: 100 µg/h). At 8 h, mean PCWP changed from 25.7 ± 5.0 mmHg by -7.7 mmHg with cinaciguat and from 25.0 ± 5.3 mmHg by -3.7 mmHg with placebo (P < 0.0001). The mean right atrial pressure changed from 12.4 ± 5.3 mmHg by -2.7 mmHg with cinaciguat and from 11.8 ± 4.9 mmHg by -0.6 mmHg with placebo (P= 0.0019). Cinaciguat also decreased the pulmonary and systemic vascular resistance and the mean arterial pressure, and increased the cardiac index (all P < 0.0001 vs. placebo). Systolic blood pressure changed by -21.6 ± 17.0 mmHg with cinaciguat and -5.0 ± 14.5 mmHg with placebo. Adverse events were experienced by 71 and 45% of patients receiving cinaciguat and placebo, respectively. No adverse effects on the 30-day mortality were seen; however, the trial was stopped prematurely due to an increased occurrence of hypotension at cinaciguat doses ≥200 µg/h. CONCLUSION: Cinaciguat unloaded the heart in patients with ADHF. However, high doses were associated with hypotension.


Assuntos
Benzoatos/administração & dosagem , Benzoatos/efeitos adversos , Proteínas Ativadoras de Guanilato Ciclase/administração & dosagem , Proteínas Ativadoras de Guanilato Ciclase/efeitos adversos , Insuficiência Cardíaca/tratamento farmacológico , Hipotensão/induzido quimicamente , Doença Aguda , Relação Dose-Resposta a Droga , Método Duplo-Cego , Término Precoce de Ensaios Clínicos , Feminino , Taxa de Filtração Glomerular/efeitos dos fármacos , Insuficiência Cardíaca/fisiopatologia , Hemodinâmica/efeitos dos fármacos , Humanos , Hipotensão/fisiopatologia , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Taquicardia Ventricular/induzido quimicamente , Resultado do Tratamento
8.
Turk Kardiyol Dern Ars ; 42 Suppl 1: 142-52, 2014 Oct.
Artigo em Turco | MEDLINE | ID: mdl-25697041

RESUMO

Chronic obstructive lung disease (COPD) and diffuse parenchymal lung diseases (DPLD), including idiopathic pulmonary fibrosis (IPF) and sarcoidosis, are associated with a high incidence of pulmonary hypertension (PH), which is linked with exercise limitation and a worse prognosis. Patients with combined pulmonary fibrosis and emphysema (CPFE) are particularly prone to the development of PH. Echocardiography and right heart catheterization are the principal modalities for the diagnosis of COPD and DPLD. For discrimination between group 1 PH patients with concomitant respiratory abnormalities and group 3 PH patients (PH caused by lung disease), patients should be transferred to a center with expertise in both PH and lung diseases for comprehensive evaluation. The task force encompassing the .authors of this article provided criteria for this discrimination and suggested using the following definitions for group 3 patients, as exemplified for COPD, IPF, and CPFE: COPD/IPF/CPFE without PH (mean pulmonary artery pressure [mPAP]<25mmHg); COPD/IPF/CPFE with PH (mPAP25mmHg); PH-COPD, PH-IPF, and PH-CPFE); COPD/IPF/CPFE with severe PH (mPAP 35 mmHg or mPAP 25 mmHg with low cardiac index [CI <2.0.l/min/m2]; severe PH-COPD, severe PH-IPF, and severe PH-CPFE). The "severe PH group" includes only a minority of chronic lung disease patients who are suspected of having strong general vascular abnormalities (remodeling) accompanying the parenchymal disease and with evidence of an exhausted circulatory reserve rather than an exhausted ventilatory reserve underlying the limitation of exercise capacity. Exertional dyspnea disproportionate to pulmonary function tests, low carbon monoxide diffusion capacity, and rapid decline of arterial oxygenation upon exercise are typical clinical features of this subgroup with poor prognosis. Studies evaluating the effect of pulmonary arterial hypertension drugs currently not approved for group 3 PH patients should focus on this severe PH group, and for the time being, these patients should be transferred to expert centers for individualized patient care. (J Am Coll Cardiol 2013;62:D109-16) ©2013 by the American College of Cardiology Foundation.

10.
Basic Res Cardiol ; 108(5): 378, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23982491

RESUMO

Immunoglobulin light chain (LC) amyloidosis (AL) results from overproduction of circulating amyloidogenic LC proteins and subsequent amyloid fibril deposition in organs. Mortality in AL amyloidosis patients is highly associated with a rapidly progressive AL cardiomyopathy, marked by profound impairment of diastolic and systolic cardiac function and significant early mortality. While myocardial fibril deposition contributes to the severe diastolic dysfunction seen in AL cardiomyopathy patients, the degree of fibril deposition has not been found to correlate with prognosis. Previously, we and others showed a direct cardiotoxic effect of amyloidogenic LC proteins (AL-LC), which may contribute to the pathophysiology and mortality observed in AL cardiomyopathy patients. However, the mechanisms underlying AL-LC related cardiotoxicity remain unknown. Mammalian stanniocalcin1 (STC1) is associated with a number of cellular processes including oxidative stress and cell death. Herein, we find that STC1 expression is elevated in cardiac tissue from AL cardiomyopathy patients, and is induced in isolated cardiomyocytes in response to AL-LC, but not non-amyloidogenic LC. STC1 overexpression in vitro recapitulates the pathophysiology of AL-LC mediated cardiotoxicity, with increased ROS production, contractile dysfunction and cell death. Overexpression of STC1 in vivo results in significant cardiac dysfunction and cell death. Genetic silencing of STC1 prevents AL-LC induced cardiotoxicity in cardiomyocytes and protects against AL-LC induced cell death and early mortality in zebrafish. The cardiotoxic effects of STC1 appears to be mediated via mitochondrial dysfunction as indicated by loss of mitochondrial membrane potential, ROS production and increased mitochondrial calcium levels. Collectively, this work identifies STC1 as a critical determinant of AL-LC cardiotoxicity.


Assuntos
Amiloidose/metabolismo , Cardiomiopatias/metabolismo , Glicoproteínas/metabolismo , Cadeias Leves de Imunoglobulina/metabolismo , Amiloidose/patologia , Animais , Cardiomiopatias/patologia , Técnicas de Silenciamento de Genes , Humanos , Immunoblotting , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Camundongos , Mitocôndrias/metabolismo , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Peixe-Zebra
11.
Proc Natl Acad Sci U S A ; 107(9): 4188-93, 2010 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-20150510

RESUMO

Patients with primary (AL) cardiac amyloidosis suffer from progressive cardiomyopathy with a median survival of less than 8 months and a 5-year survival of <10%. Contributing to this poor prognosis is the fact that these patients generally do not tolerate standard heart failure therapies. The molecular mechanisms underlying this deadly form of heart disease remain unclear. Although interstitial amyloid fibril deposition of Ig light chain proteins is a major cause of cardiac dysfunction in AL cardiac amyloidosis, we have previously shown that amyloid precursor proteins directly impair cardiac function at the cellular and isolated organ levels, independent of fibril formation. In this study, we report that amyloidogenic light chain (AL-LC) proteins provoke oxidative stress, cellular dysfunction, and apoptosis in isolated adult cardiomyocytes through activation of p38 mitogen-activated protein kinase (MAPK). AL-LC-induced p38 activation was found to be independent of the upstream MAPK kinase, MKK3/6, and instead depends upon transforming growth factor-beta-activated protein kinase-1 binding protein-1 (TAB1)-mediated p38alpha MAPK autophosphorylation. Treatment of cardiomyocytes with SB203580, a selective p38 MAPK inhibitor, significantly attenuated AL-LC-induced oxidative stress, cellular dysfunction, and apoptosis. Our data provide a unique mechanistic insight into the pathogenesis of AL-LC cardiac toxicity and suggest that TAB1-mediated p38alpha MAPK autophosphorylation may serve as an important event leading to cardiac dysfunction and subsequent heart failure.


Assuntos
Amiloide/fisiologia , Apoptose , Miocárdio/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Ativação Enzimática , Humanos , Imidazóis/farmacologia , Contração Miocárdica , Miocárdio/citologia , Miocárdio/enzimologia , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores
12.
JAMA ; 309(12): 1268-77, 2013 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-23478662

RESUMO

IMPORTANCE: Studies in experimental and human heart failure suggest that phosphodiesterase-5 inhibitors may enhance cardiovascular function and thus exercise capacity in heart failure with preserved ejection fraction (HFPEF). OBJECTIVE: To determine the effect of the phosphodiesterase-5 inhibitor sildenafil compared with placebo on exercise capacity and clinical status in HFPEF. DESIGN: Multicenter, double-blind, placebo-controlled, parallel-group, randomized clinical trial of 216 stable outpatients with HF, ejection fraction ≥50%, elevated N-terminal brain-type natriuretic peptide or elevated invasively measured filling pressures, and reduced exercise capacity. Participants were randomized from October 2008 through February 2012 at 26 centers in North America. Follow-up was through August 30, 2012. INTERVENTIONS: Sildenafil (n = 113) or placebo (n = 103) administered orally at 20 mg, 3 times daily for 12 weeks, followed by 60 mg, 3 times daily for 12 weeks. MAIN OUTCOME MEASURES: Primary end point was change in peak oxygen consumption after 24 weeks of therapy. Secondary end points included change in 6-minute walk distance and a hierarchical composite clinical status score (range, 1-n, a higher value indicates better status; expected value with no treatment effect, 95) based on time to death, time to cardiovascular or cardiorenal hospitalization, and change in quality of life for participants without cardiovascular or cardiorenal hospitalization at 24 weeks. RESULTS: Median age was 69 years, and 48% of patients were women. At baseline, median peak oxygen consumption (11.7 mL/kg/min) and 6-minute walk distance (308 m) were reduced. The median E/e' (16), left atrial volume index (44 mL/m2), and pulmonary artery systolic pressure (41 mm Hg) were consistent with chronically elevated left ventricular filling pressures. At 24 weeks, median (IQR) changes in peak oxygen consumption (mL/kg/min) in patients who received placebo (-0.20 [IQR, -0.70 to 1.00]) or sildenafil (-0.20 [IQR, -1.70 to 1.11]) were not significantly different (P = .90) in analyses in which patients with missing week-24 data were excluded, and in sensitivity analysis based on intention to treat with multiple imputation for missing values (mean between-group difference, 0.01 mL/kg/min, [95% CI, -0.60 to 0.61]). The mean clinical status rank score was not significantly different at 24 weeks between placebo (95.8) and sildenafil (94.2) (P = .85). Changes in 6-minute walk distance at 24 weeks in patients who received placebo (15.0 m [IQR, -26.0 to 45.0]) or sildenafil (5.0 m [IQR, -37.0 to 55.0]; P = .92) were also not significantly different. Adverse events occurred in 78 placebo patients (76%) and 90 sildenafil patients (80%). Serious adverse events occurred in 16 placebo patients (16%) and 25 sildenafil patients (22%). CONCLUSION AND RELEVANCE: Among patients with HFPEF, phosphodiesterase-5 inhibition with administration of sildenafil for 24 weeks, compared with placebo, did not result in significant improvement in exercise capacity or clinical status. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00763867.


Assuntos
Tolerância ao Exercício , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/fisiopatologia , Inibidores da Fosfodiesterase 5/uso terapêutico , Piperazinas/uso terapêutico , Sulfonas/uso terapêutico , Idoso , Pressão Sanguínea , Método Duplo-Cego , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Consumo de Oxigênio , Purinas/uso terapêutico , Citrato de Sildenafila , Volume Sistólico , Resultado do Tratamento , Caminhada
13.
JAMA ; 310(23): 2533-43, 2013 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-24247300

RESUMO

IMPORTANCE: Small studies suggest that low-dose dopamine or low-dose nesiritide may enhance decongestion and preserve renal function in patients with acute heart failure and renal dysfunction; however, neither strategy has been rigorously tested. OBJECTIVE: To test the 2 independent hypotheses that, compared with placebo, addition of low-dose dopamine (2 µg/kg/min) or low-dose nesiritide (0.005 µg/kg/min without bolus) to diuretic therapy will enhance decongestion and preserve renal function in patients with acute heart failure and renal dysfunction. DESIGN, SETTING, AND PARTICIPANTS: Multicenter, double-blind, placebo-controlled clinical trial (Renal Optimization Strategies Evaluation [ROSE]) of 360 hospitalized patients with acute heart failure and renal dysfunction (estimated glomerular filtration rate of 15-60 mL/min/1.73 m2), randomized within 24 hours of admission. Enrollment occurred from September 2010 to March 2013 across 26 sites in North America. INTERVENTIONS: Participants were randomized in an open, 1:1 allocation ratio to the dopamine or nesiritide strategy. Within each strategy, participants were randomized in a double-blind, 2:1 ratio to active treatment or placebo. The dopamine (n = 122) and nesiritide (n = 119) groups were independently compared with the pooled placebo group (n = 119). MAIN OUTCOMES AND MEASURES: Coprimary end points included 72-hour cumulative urine volume (decongestion end point) and the change in serum cystatin C from enrollment to 72 hours (renal function end point). RESULTS: Compared with placebo, low-dose dopamine had no significant effect on 72-hour cumulative urine volume (dopamine, 8524 mL; 95% CI, 7917-9131 vs placebo, 8296 mL; 95% CI, 7762-8830 ; difference, 229 mL; 95% CI, -714 to 1171 mL; P = .59) or on the change in cystatin C level (dopamine, 0.12 mg/L; 95% CI, 0.06-0.18 vs placebo, 0.11 mg/L; 95% CI, 0.06-0.16; difference, 0.01; 95% CI, -0.08 to 0.10; P = .72). Similarly, low-dose nesiritide had no significant effect on 72-hour cumulative urine volume (nesiritide, 8574 mL; 95% CI, 8014-9134 vs placebo, 8296 mL; 95% CI, 7762-8830; difference, 279 mL; 95% CI, -618 to 1176 mL; P = .49) or on the change in cystatin C level (nesiritide, 0.07 mg/L; 95% CI, 0.01-0.13 vs placebo, 0.11 mg/L; 95% CI, 0.06-0.16; difference, -0.04; 95% CI, -0.13 to 0.05; P = .36). Compared with placebo, there was no effect of low-dose dopamine or nesiritide on secondary end points reflective of decongestion, renal function, or clinical outcomes. CONCLUSION AND RELEVANCE: In participants with acute heart failure and renal dysfunction, neither low-dose dopamine nor low-dose nesiritide enhanced decongestion or improved renal function when added to diuretic therapy. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01132846.


Assuntos
Dopamina/administração & dosagem , Insuficiência Cardíaca/tratamento farmacológico , Nefropatias/tratamento farmacológico , Natriuréticos/administração & dosagem , Peptídeo Natriurético Encefálico/administração & dosagem , Vasodilatadores/administração & dosagem , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Cistatina C/sangue , Diuréticos/uso terapêutico , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Taxa de Filtração Glomerular , Insuficiência Cardíaca/complicações , Humanos , Rim/fisiopatologia , Nefropatias/complicações , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Urina
14.
Circulation ; 124(13): 1442-51, 2011 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-21875912

RESUMO

BACKGROUND: Exercise oscillatory ventilation (EOV) is a noninvasive parameter that potently predicts outcomes in systolic heart failure (HF). However, mechanistic insights into EOV have been limited by the absence of studies relating EOV to invasive hemodynamic measurements and blood gases performed during exercise. METHODS AND RESULTS: Fifty-six patients with systolic HF (mean±SEM age, 59±2 years; left ventricular ejection fraction, 30±1%) and 19 age-matched control subjects were studied with incremental cardiopulmonary exercise testing. Fick cardiac outputs, filling pressures, and arterial blood gases were measured at 1-minute intervals during exercise. We detected EOV in 45% of HF (HF+EOV) patients and in none of the control subjects. The HF+EOV group did not differ from the HF patients without EOV (HF-EOV) in age, sex, body mass index, left ventricular ejection fraction, or origin of HF. Univariate predictors of the presence of EOV in HF, among measurements performed during exercise, included higher right atrial pressure and pulmonary capillary wedge pressure and lower cardiac index (CI) but not Paco2 or Pao2. Multivariate logistic regression identified that low exercise CI is the strongest predictor of EOV (odds ratio, 1.39 for each 1.0-L · min(-1) · m(-2) decrement in CI; 95% confidence interval, 1.14-1.70; P=0.001). Among HF patients with EOV, exercise CI was inversely related to EOV cycle length (R=-0.71) and amplitude (R=-0.60; both P<0.001). In 11 HF+EOV subjects treated with 12 weeks of sildenafil, EOV cycle length and amplitude decreased proportionately to increases in CI. CONCLUSION: Exercise oscillatory ventilation is closely related to reduced CI and elevated filling pressures during exercise and may be an important surrogate for exercise-induced hemodynamic impairment in HF patients. Clinical Trial Registration- URL: http://www.clinicaltrials.gov. Unique identifier: NCT00309790.


Assuntos
Teste de Esforço/métodos , Insuficiência Cardíaca Sistólica , Piperazinas/uso terapêutico , Mecânica Respiratória/fisiologia , Sulfonas/uso terapêutico , Gasometria , Dióxido de Carbono/sangue , Débito Cardíaco/efeitos dos fármacos , Débito Cardíaco/fisiologia , Teste de Esforço/efeitos dos fármacos , Feminino , Insuficiência Cardíaca Sistólica/diagnóstico , Insuficiência Cardíaca Sistólica/tratamento farmacológico , Insuficiência Cardíaca Sistólica/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Inibidores da Fosfodiesterase 5/uso terapêutico , Esforço Físico/fisiologia , Valor Preditivo dos Testes , Troca Gasosa Pulmonar/efeitos dos fármacos , Troca Gasosa Pulmonar/fisiologia , Pressão Propulsora Pulmonar/efeitos dos fármacos , Pressão Propulsora Pulmonar/fisiologia , Purinas/uso terapêutico , Mecânica Respiratória/efeitos dos fármacos , Descanso/fisiologia , Citrato de Sildenafila , Volume Sistólico/efeitos dos fármacos , Volume Sistólico/fisiologia , Pressão Ventricular/efeitos dos fármacos , Pressão Ventricular/fisiologia
15.
Am Heart J ; 164(5): 763-770.e3, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23137508

RESUMO

BACKGROUND: Acute decompensated heart failure (ADHF) occurs with preserved (heart failure with preserved ejection fraction [HFpEF] ≥50%) or reduced (heart failure with reduced ejection fraction [HFrEF] <50%) ejection fraction. Natriuretic peptide (NP) levels are lower in HFpEF than HFrEF. We hypothesized that lower NP levels in HFpEF may be associated with other differences in biomarkers, specifically, renin-angiotensin-aldosterone system (RAAS) activation, oxidative stress, and a biomarker that reflects collagen synthesis. METHODS: In this prespecified ancillary analysis of patients with ADHF enrolled in the Diuretic Optimization Strategies Evaluation study, clinical features and N-terminal pro-B-type NP, cystatin C, plasma renin activity, aldosterone, oxidative stress (uric acid), and procollagen type III N-terminal peptide were compared in HFpEF and HFrEF at enrollment and 60-day follow-up. RESULTS: Compared with HFrEF (n = 219), HFpEF (n = 81) patients were older, heavier, more commonly female, less treated with RAAS antagonists, but with similar New York Heart Association class, jugular venous pressure, and edema severity. N-terminal pro-B-type NP was lower, and systolic blood pressure and cystatin C were higher in HFpEF. Despite higher systolic blood pressure and less RAAS antagonist use in HFpEF, plasma renin activity and aldosterone levels were similar in HFpEF and HFrEF as were uric acid and procollagen type III N-terminal peptide levels. Changes in biomarker levels from enrollment to 60 days were similar between HFrEF (n = 149) and HFpEF (n = 50). CONCLUSION: Lower NP levels in decompensated HFpEF occur in association with similar ADHF severity, more impaired vascular and renal function but similar elevation of biomarkers that reflect RAAS activation, oxidative stress, and collagen synthesis as in HFrEF.


Assuntos
Biomarcadores/sangue , Diuréticos/administração & dosagem , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/tratamento farmacológico , Peptídeos Natriuréticos/sangue , Sistema Renina-Angiotensina , Volume Sistólico , Idoso , Idoso de 80 Anos ou mais , Aldosterona/sangue , Pressão Sanguínea , Cistatina C/sangue , Método Duplo-Cego , Esquema de Medicação , Feminino , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Peptídeo Natriurético Encefálico/sangue , Estresse Oxidativo/efeitos dos fármacos , Fragmentos de Peptídeos/sangue , Valor Preditivo dos Testes , Pró-Colágeno/sangue , Estudos Prospectivos , Renina/sangue , Sistema Renina-Angiotensina/efeitos dos fármacos , Índice de Gravidade de Doença , Ácido Úrico/sangue
16.
J Card Fail ; 18(8): 626-34, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22858078

RESUMO

BACKGROUND: Elderly patients with heart failure (HF) have a worse prognosis than younger patients. We wished to study whether elders benefit from natriuretic peptide-guided HF care in this single-center study. METHODS AND RESULTS: A total of 151 patients with HF resulting from left ventricular systolic dysfunction (LVSD) were treated with HF treatment by standard-of-care (SOC) management or guided by N-terminal pro-B type natriuretic peptide (NT-proBNP) values (with a goal to lower NT-proBNP ≤1000 pg/mL) over 10 months. The primary end point for this post-hoc analysis was total cardiovascular events in 2 age categories (<75 and ≥75 years). In those ≥75 years of age (n = 38), NT-proBNP values increased in the SOC arm (2570 to 3523 pg/mL, P = .01), but decreased in the NT-proBNP-guided arm (2664 to 1418 pg/mL, P = .001). Elderly patients treated with SOC management had the highest rate of cardiovascular events, whereas the elderly with NT-proBNP management had the lowest rate of cardiovascular events (1.76 events per patient versus 0.71 events per patient, P = .03); the adjusted logistic odds for cardiovascular events related to NT-proBNP-guided care for elders was 0.24 (P = .008), whereas in those <75 years (n = 113), the adjusted logistic odds for events following NT-proBNP-guided care was 0.61 (P = .10). CONCLUSIONS: Natriuretic peptide-guided HF care was well tolerated and resulted in substantial improvement in cardiovascular event rates in elders (ClinicalTrials.Gov #00351390).


Assuntos
Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/tratamento farmacológico , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Envelhecimento , Anti-Hipertensivos/uso terapêutico , Progressão da Doença , Feminino , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Prognóstico , Estatística como Assunto , Resultado do Tratamento , Ultrassonografia , Disfunção Ventricular Esquerda/patologia
17.
J Card Fail ; 18(3): 176-82, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22385937

RESUMO

BACKGROUND: Worsening renal function is common among patients hospitalized for acute decompensated heart failure (ADHF). When this occurs, subsequent management decisions often pit the desire for effective decongestion against concerns about further worsening renal function. There are no evidence-based treatments or guidelines to assist in these difficult management decisions. Ultrafiltration is a potentially attractive alternative to loop diuretics for the management of fluid overload in patients with ADHF and worsening renal function. METHODS AND RESULTS: The National Heart, Lung, and Blood Institute Heart Failure Clinical Research Network designed a clinical trial to determine if ultrafiltration results in improved renal function and relief of congestion compared with stepped pharmacologic care when assessed 96 hours after randomization in patients with ADHF and cardiorenal syndrome. Enrollment began in June 2008. This paper describes the rationale and design of the Cardiorenal Rescue Study in Acute Decompensated Heart Failure (CARRESS-HF). CONCLUSIONS: Treating the signs and symptoms of congestion in ADHF is often complicated by worsening renal function. CARRESS-HF compares treatment strategies (ultrafiltration vs stepped pharmacologic care) for the management of worsening renal function in patients with ADHF. The results of the CARRESS-HF trial are expected to provide information and evidence as to the most appropriate approaches for treating this challenging patient population.


Assuntos
Pesquisa Biomédica/métodos , Síndrome Cardiorrenal/epidemiologia , Síndrome Cardiorrenal/terapia , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/terapia , Doença Aguda , Pesquisa Biomédica/tendências , Síndrome Cardiorrenal/diagnóstico , Insuficiência Cardíaca/diagnóstico , Hemofiltração/métodos , Humanos , Estudos Prospectivos
19.
Circulation ; 121(10): 1216-26, 2010 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-20194882

RESUMO

BACKGROUND: Heart failure is a debilitating condition resulting in severe disability and death. In a subset of cases, clustered as idiopathic dilated cardiomyopathy (iDCM), the origin of heart failure is unknown. In the brain of patients with dementia, proteinaceous aggregates and abnormal oligomeric assemblies of beta-amyloid impair cell function and lead to cell death. METHODS AND RESULTS: We have similarly characterized fibrillar and oligomeric assemblies in the hearts of iDCM patients, pointing to abnormal protein aggregation as a determinant of iDCM. We also showed that oligomers alter myocyte Ca(2+) homeostasis. Additionally, we have identified 2 new sequence variants in the presenilin-1 (PSEN1) gene promoter leading to reduced gene and protein expression. We also show that presenilin-1 coimmunoprecipitates with SERCA2a. CONCLUSIONS: On the basis of these findings, we propose that 2 mechanisms may link protein aggregation and cardiac function: oligomer-induced changes on Ca(2+) handling and a direct effect of PSEN1 sequence variants on excitation-contraction coupling protein function.


Assuntos
Cardiomiopatia Dilatada/genética , Cardiomiopatia Dilatada/metabolismo , Presenilina-1/genética , Proteínas/química , Adulto , Idoso , Amiloide/análise , Peptídeos beta-Amiloides/análise , Cálcio/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Mutação , Polimorfismo de Nucleotídeo Único , Presenilina-2/genética
20.
J Card Fail ; 16(2): 106-13, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20142021

RESUMO

BACKGROUND: Indications for implantable cardioverter-defibrillators (ICDs) in heart failure (HF) are expanding and may include more than 1 million patients. This study examined patient expectations from ICDs for primary prevention of sudden death in HF. METHODS AND RESULTS: Study participants (n = 105) had an EF <35% and symptomatic HF, without history of ventricular tachycardia/fibrillation or syncope. Subjects completed a written survey about perceived ICD benefits, survival expectations, and circumstances under which they might deactivate defibrillation. Mean age was 58, LVEF 21%, 40% were New York Heart Association Class III-IV, and 65% already had a primary prevention ICD. Most patients anticipated more than10 years survival despite symptomatic HF. Nearly 54% expected an ICD to save >or=50 lives per 100 during 5 years. ICD recipients expressed more confidence that the device would save their own lives compared with those without an ICD (P < .001). Despite understanding the ease of deactivation, 70% of ICD recipients indicated they would keep the ICD on even if dying of cancer, 55% even if having daily shocks, and none would inactivate defibrillation even if suffering constant dyspnea at rest. CONCLUSIONS: HF patients anticipate long survival, overestimate survival benefits conferred by ICDs, and express reluctance to deactivate their devices even for end-stage disease.


Assuntos
Morte Súbita Cardíaca/prevenção & controle , Desfibriladores Implantáveis , Insuficiência Cardíaca/psicologia , Insuficiência Cardíaca/terapia , Educação de Pacientes como Assunto , Adulto , Idoso , Estudos de Coortes , Feminino , Insuficiência Cardíaca/mortalidade , Humanos , Expectativa de Vida/tendências , Masculino , Pessoa de Meia-Idade , Educação de Pacientes como Assunto/tendências , Satisfação do Paciente , Taxa de Sobrevida/tendências
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa