JEFFERSON LUIS VIEIRA
Projetos de Pesquisa
Unidades Organizacionais
Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina - Médico
2 resultados
Resultados de Busca
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- Respiratory Filter Reduces the Cardiovascular Effects Associated With Diesel Exhaust Exposure A Randomized, Prospective, Double-Blind, Controlled Study of Heart Failure: The FILTER-HF Trial(2016) VIEIRA, Jefferson L.; GUIMARAES, Guilherme V.; ANDRE, Paulo A. de; CRUZ, Fatima D.; SALDIVA, Paulo H. Nascimento; BOCCHI, Edimar A.OBJECTIVES The goal of this study was to test the effects of a respiratory filter intervention (filter) during controlled pollution exposure. BACKGROUND Air pollution is considered a risk factor for heart failure (HF) decompensation and mortality. METHODS This study was a double-blind, randomized to order, controlled, 3-way crossover, single-center clinical trial. It enrolled 26 patients with HF and 15 control volunteers. Participants were exposed in 3 separate sessions to clean air, unfiltered diesel exhaust exposure (DE), or filtered DE. Endpoints were endothelial function assessed by using the reactive hyperemia index (RHi), arterial stiffness, serum biomarkers, 6-min walking distance, and heart rate variability. RESULTS In patients with HF, DE was associated with a worsening in RHi from 2.17 (interquartile range [IQR]: 1.8 to 2.5) to 1.72 (IQR: 1.5 to 2.2; p = 0.002) and an increase in B-type natriuretic peptide (BNP) from 47.0 pg/ml (IQR: 17.3 to 118.0 pg/ml) to 66.5 pg/ml (IQR: 26.5 to 155.5 pg/ml; p = 0.004). Filtration reduced the particulate concentration (325 +/- 31 mu g/m(3) vs. 25 +/- 6 mu g/m(3); p < 0.001); in the group with HF, filter was associated with an improvement in RHi from 1.72 (IQR: 1.5 to 2.2) to 2.06 (IQR: 1.5 to 2.6; p = 0.019) and a decrease in BNP from 66.5 pg/ml (IQR: 26.5 to 155.5 pg/ml) to 44.0 pg/ml (IQR: 20.0 to 110.0 pg/ml; p = 0.015) compared with DE. In both groups, DE decreased the 6-min walking distance and arterial stiffness, although filter did not change these responses. DE had no effect on heart rate variability or exercise testing. CONCLUSIONS To our knowledge, this trial is the first to show that a filter can reduce both endothelial dysfunction and BNP increases in patients with HF during DE. Given these potential benefits, the widespread use of filters in patients with HF exposed to traffic-derived air pollution may have beneficial public health effects and reduce the burden of HF. (Effects of Air Pollution Exposure Reduction by Filter Mask on Heart Failure; NCT01960920) (C) 2016 by the American College of Cardiology Foundation.
- Systemic effects of controlled exposure to diesel exhaust: a meta-analysis from randomized controlled trials(2017) VIEIRA, Jefferson Luis; MACEDO, Francisco Yuri; BENJO, Alexandre Miguel; GUIMARAES, Guilherme V.; CONTRERAS, Johanna Paola; BOCCHI, Edimar A.Introduction: Ambient air pollution is associated with adverse cardiovascular events. This meta-analysis aimed to investigate the short-term association between air pollution and cardiovascular effects on healthy volunteers. Methods: We searched databases to identify randomized trials with controlled human exposures to either of two models for studying ambient particulate matter: diesel-exhaust or concentrated ambient particles. Estimates of size effect were performed using standardized mean difference (SMD). Heterogeneity was assessed with I-2 statistics. Outcomes were vascular function estimated by forearm blood flow (FBF), blood pressure, heart rate, and blood analysis. Results: Database searches yielded 17 articles (n=342) with sufficient information for meta-analyses. High levels of heterogeneity for the some outcomes were analyzed using random-effects model. The pooled effect estimate showed that short-term exposure to air pollution impaired FBF response from 2.7 to 2.5mL/100mL tissue/min (SMD 0.404; p=.006). There was an increase in 5000 platelet/mm(3) following pollution exposure (SMD 0.390; p=.050) but no significant differences for other outcomes. Conclusion: Controlled human exposures to air pollution are associated with the surrogates of vascular dysfunction and increase in platelet count, which might be related to adverse cardiovascular events. Given the worldwide prevalence of exposure to air pollution, these findings are relevant for public health.