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1.
Artigo em Inglês | MEDLINE | ID: mdl-31743617

RESUMO

BACKGROUND: The exercise intolerance in chronic heart failure with reduced ejection fraction (HFrEF) is mostly attributed to alterations in skeletal muscle. However, the mechanisms underlying the skeletal myopathy in patients with HFrEF are not completely understood. We hypothesized that (i) aerobic exercise training (AET) and inspiratory muscle training (IMT) would change skeletal muscle microRNA-1 expression and downstream-associated pathways in patients with HFrEF and (ii) AET and IMT would increase leg blood flow (LBF), functional capacity, and quality of life in these patients. METHODS: Patients age 35 to 70 years, left ventricular ejection fraction (LVEF) ≤40%, New York Heart Association functional classes II-III, were randomized into control, IMT, and AET groups. Skeletal muscle changes were examined by vastus lateralis biopsy. LBF was measured by venous occlusion plethysmography, functional capacity by cardiopulmonary exercise test, and quality of life by Minnesota Living with Heart Failure Questionnaire. All patients were evaluated at baseline and after 4 months. RESULTS: Thirty-three patients finished the study protocol: control (n = 10; LVEF = 25 ± 1%; six males), IMT (n = 11; LVEF = 31 ± 2%; three males), and AET (n = 12; LVEF = 26 ± 2%; seven males). AET, but not IMT, increased the expression of microRNA-1 (P = 0.02; percent changes = 53 ± 17%), decreased the expression of PTEN (P = 0.003; percent changes = -15 ± 0.03%), and tended to increase the p-AKTser473 /AKT ratio (P = 0.06). In addition, AET decreased HDAC4 expression (P = 0.03; percent changes = -40 ± 19%) and upregulated follistatin (P = 0.01; percent changes = 174 ± 58%), MEF2C (P = 0.05; percent changes = 34 ± 15%), and MyoD expression (P = 0.05; percent changes = 47 ± 18%). AET also increased muscle cross-sectional area (P = 0.01). AET and IMT increased LBF, functional capacity, and quality of life. Further analyses showed a significant correlation between percent changes in microRNA-1 and percent changes in follistatin mRNA (P = 0.001, rho = 0.58) and between percent changes in follistatin mRNA and percent changes in peak VO2 (P = 0.004, rho = 0.51). CONCLUSIONS: AET upregulates microRNA-1 levels and decreases the protein expression of PTEN, which reduces the inhibitory action on the PI3K-AKT pathway that regulates the skeletal muscle tropism. The increased levels of microRNA-1 also decreased HDAC4 and increased MEF2c, MyoD, and follistatin expression, improving skeletal muscle regeneration. These changes associated with the increase in muscle cross-sectional area and LBF contribute to the attenuation in skeletal myopathy, and the improvement in functional capacity and quality of life in patients with HFrEF. IMT caused no changes in microRNA-1 and in the downstream-associated pathway. The increased functional capacity provoked by IMT seems to be associated with amelioration in the respiratory function instead of changes in skeletal muscle. ClinicalTrials.gov (Identifier: NCT01747395).

2.
J Cardiovasc Electrophysiol ; 30(11): 2591-2598, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31544272

RESUMO

INTRODUCTION: The muscular metaboreflex, whose activation regulates blood flow during isometric and aerobic exercise, is blunted in patients with heart failure (HF), and cardiac resynchronization therapy (CRT) may restore this regulatory reflex. OBJECTIVE: To evaluate metaboreflex responses after CRT. METHODS: Thirteen HF patients and 12 age-matched healthy control subjects underwent the following evaluations (pre- and post-CRT implantation in the patient group): (a) heart rate, blood pressure, and forearm blood flow measurements; (b) muscle sympathetic nerve activity (MSNA) evaluation; and (c) peak oxygen consumption (VO2peak ). Examinations were performed at rest, during moderate isometric exercise (IE), and during forearm ischemia (metaboreflex activation). The primary outcome was the increment in MSNA during limb ischemia compared to the rest moment (ΔMSNA rest to metaboreflex activation). RESULTS: After CRT, rest MSNA decreased in the HF participants: 50.4 ± 9.2 bursts/min pre-CRT vs 34.0 ± 14.4 bursts/min post-CRT, P = .001, accompanied by an improvement in systolic blood pressure and in rate-pressure product. MSNA during limb ischemia decreased: 56.6 ± 11.5 bursts/min pre-CRT vs 43.6 ± 12.7 bursts/min post-CRT, P = .001, and the ΔMSNA rest to metaboreflex activation increased: 0% (interquartile range [IQR)], -7 to 9) vs 13% (IQR, 5-30), P = .03. An augmentation of mean blood pressure during limb ischemia post-CRT was noticed: 94 mmHg (IQR, 81-104) vs 110 mmHg (IQR, 100-117), P = .04. CRT improved VO2peak , and this improvement was correlated with diminution in ΔMSNA pre- to post-CRT at rest moment (rs = -0.74, P = .006). CONCLUSION: CRT provides metaboreflex sensitization and MSNA enhancement. The restoration of sympathetic responsiveness correlates with the improvement in functional capacity.

3.
Ther Adv Chronic Dis ; 10: 2040622319868376, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31489153

RESUMO

Background: Studies have shown significant benefits of exercise therapy in heart failure (HF) with a reduced ejection fraction (HFrEF) and HF with a preserved ejection fraction (HFpEF). The mechanisms responsible for the beneficial effect of exercise in HFrEF and HFpEF are still unclear. We hypothesized that the effect of exercise on myocardial remodeling may explain its beneficial effect. Methods: IMAGING-REHAB-HF is a single-center, randomized, controlled clinical trial using cardiac magnetic resonance imaging, vasomotor endothelial function, cardiac sympathetic activity imaging and serum biomarkers to compare the effect of exercise therapy in HFpEF (LVEF ≥ 45%) and HFrEF (LVEF < 45%). Subjects will be assessed at baseline and after 4 months. The exercise program will consist of three 60-min exercise sessions/week. The primary endpoints are the effect of exercise on myocardial extracellular volume (ECV), left ventricular (LV) systolic function, LV mass, LV mass-to-volume and LV cardiomyocyte volume. Secondary endpoints include the effect of exercise on vasomotor endothelial function, cardiac sympathetic activity and plasmatic biomarkers. Patients will be allocated in a 2:1 fashion to supervised exercise program or usual care. A total sample size of 90 patients, divided into two groups according to LVEF:HFpEF group (45 patients:30 in the intervention arm and 15 in the control arm) and HFrEF group (45 patients:30 in the intervention arm and 15 in the control arm) - will be necessary to achieve adequate power. Conclusion: This will be the first study to evaluate the benefits of a rehabilitation program on cardiac remodeling in HF patients. The unique design of our study may provide unique data to further elucidate the mechanisms involved in reverse cardiac remodeling after exercise in HFpEF and HFrEF patients.

4.
Rev. Soc. Cardiol. Estado de Säo Paulo ; 29(3 Supl): 306-313, jul.-set. 2019. tab
Artigo em Português | LILACS | ID: biblio-1023176

RESUMO

A doença arterial coronariana (DAC) é umas das doenças cardiovasculares que mais mata no Brasil e no mundo. É uma doença multifatorial, associada a fatores de risco modificáveis. Além dos tratamentos convencionais, é recomendado que pacientes com DAC também incluam modificações no estilo de vida e programas de reabilitação cardiovascular com ênfase no exercício físico (RCEE) em seu tratamento. Sabidamente, o exercício físico regular somado às mudanças no estilo de vida contribui para a diminuição do avanço da doença aterosclerótica e da mortalidade dos pacientes com DAC. Além disso, o exercício físico tem impacto benéfico na capacidade funcional e qualidade de vida. Um programa de RCEE é uma estratégia eficaz, segura e com excelente razão de custo-benefício para o tratamento da DAC. Contudo, mesmo sendo uma terapia recomendada pelos principais órgãos de saúde, no Brasil as políticas públicas de saúde são extremamente escassas e a quantidade de centros especializados que oferecem a RCEE também é baixa. Problemas de adesão, participação e motivação são evidentes quando os programas são avaliados. Esta revisão mostra os principais estudos que, ao longo das últimas décadas, deram base para as recomendações da RCEE e faz uma análise crítica do cenário atual, deixando claro que novas estratégias de atuação e monitoramento devem ser exploradas e incentivadas para que os programas de RCEE sejam incluídos efetivamente no tratamento dos pacientes com DAC


Coronary artery disease (CAD) is one of the most lethal cardiovascular diseases both in Brazil and worldwide. It is a multifactorial disease associated with modifiable risk factors. In addition to conventional treatments, it is recommended that patients with CAD also include lifestyle changes and exercise-based cardiovascular rehabilitation (CR) programs in their treatment. It is well known that regular physical exercise combined with lifestyle changes contributes to a reduction in the progression of atherosclerosis and in mortality in patients with CAD. Moreover, physical exercise has a beneficial impact on functional capacity and quality of life. A CR program is an effective, safe strategy for the treatment of CAD with an excellent cost-benefit ratio. However, even though it is a therapy recommended by the main health agencies, public health policies in Brazil are extremely scarce and the number of specialized centers that offer CR is low. Problems of adherence, participation, and motivation are evident when these programs are evaluated. This review looks at the main studies that have been the basis for the recommendations of CR over last decades and critically analyzes the current scenario, making it clear that new strategies for action and monitoring should be explored and encouraged such that CR programs will be included effectively in the treatment of patients with CAD


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Doença da Artéria Coronariana , Exercício , Reabilitação Cardíaca/métodos , Qualidade de Vida , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/terapia , Doença Crônica/mortalidade , Fatores de Risco , Placa Aterosclerótica , Frequência Cardíaca
7.
Eur J Prev Cardiol ; 24(4): 365-372, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27956555

RESUMO

Background Exercise training improves neurovascular control and functional capacity in heart failure (HF) patients. However, the influence of the aetiology on these benefits is unknown. We compared the effects of exercise training on neurovascular control and functional capacity in idiopathic, ischaemic and hypertensive HF patients. Design Subjects consisted of 45 exercise-trained HF patients from our database (2000-2015), aged 40-70 years old, functional class II/III and ejection fraction ≤40%, and they were divided into three groups: idiopathic ( n = 11), ischaemic ( n = 18) and hypertensive ( n = 16). Methods Functional capacity was determined by cardiopulmonary exercise testing. Muscle sympathetic nerve activity (MSNA) was recorded by microneurography. Forearm blood flow (FBF) was measured by venous occlusion plethysmography. Results Four months of exercise training significantly reduced MSNA and significantly increased FBF in all groups. However, the relative reduction in MSNA was greater in hypertensive patients compared with that in idiopathic patients (frequency: -34% vs . -15%, p = 0.01; incidence: -31% vs . -12%, p = 0.02). No differences were found between hypertensive patients and ischaemic patients. The relative increase in FBF was greater in hypertensive patients than in ischaemic and idiopathic patients (42% vs. 15% and 17%, respectively, p = 0.02). The relative increase in forearm vascular conductance was greater in hypertensive patients compared with those in ischaemic and idiopathic patients (57% vs . 13% and 26%, respectively, p = 0.001). Exercise training significantly and similarly increased peak oxygen consumption in all groups. Conclusion The exercise-induced improvement in neurovascular control is more pronounced in hypertensive HF patients than in idiopathic and ischaemic HF patients. The increase in functional capacity is independent of aetiology.


Assuntos
Terapia por Exercício , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/reabilitação , Hipertensão/complicações , Isquemia Miocárdica/complicações , Adulto , Idoso , Feminino , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional/fisiologia , Estudos Retrospectivos , Sistema Nervoso Simpático/fisiopatologia , Resultado do Tratamento
8.
Am J Physiol Heart Circ Physiol ; 311(5): H1180-H1188, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27591218

RESUMO

Heart failure (HF) is characterized by decreased exercise capacity, attributable to neurocirculatory and skeletal muscle factors. Cardiac resynchronization therapy (CRT) and exercise training have each been shown to decrease muscle sympathetic nerve activity (MSNA) and increase exercise capacity in patients with HF. We hypothesized that exercise training in the setting of CRT would further reduce MSNA and vasoconstriction and would increase Ca2+-handling gene expression in skeletal muscle in patients with chronic systolic HF. Thirty patients with HF, ejection fraction <35% and CRT for 1 mo, were randomized into two groups: exercise-trained (ET, n = 14) and untrained (NoET, n = 16) groups. The following parameters were compared at baseline and after 4 mo in each group: V̇o2 peak, MSNA (microneurography), forearm blood flow, and Ca2+-handling gene expression in vastus lateralis muscle. After 4 mo, exercise duration and V̇o2 peak were significantly increased in the ET group (P = 0.04 and P = 0.01, respectively), but not in the NoET group. MSNA was significantly reduced in the ET (P = 0.001), but not in NoET, group. Similarly, forearm vascular conductance significantly increased in the ET (P = 0.0004), but not in the NoET, group. The expression of the Na+/Ca2+ exchanger (P = 0.01) was increased, and ryanodine receptor expression was preserved in ET compared with NoET. In conclusion, the exercise training in the setting of CRT improves exercise tolerance and neurovascular control and alters Ca2+-handling gene expression in the skeletal muscle of patients with systolic HF. These findings highlight the importance of including exercise training in the treatment of patients with HF even following CRT.


Assuntos
Cálcio/metabolismo , Terapia de Ressincronização Cardíaca , Terapia por Exercício , Exercício , Insuficiência Cardíaca/terapia , Acoplamento Neurovascular , Músculo Quadríceps/metabolismo , Sistema Nervoso Simpático/metabolismo , Ecocardiografia , Teste de Esforço , Tolerância ao Exercício , Feminino , Antebraço/irrigação sanguínea , Expressão Gênica , Insuficiência Cardíaca/genética , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/inervação , Músculo Esquelético/metabolismo , Consumo de Oxigênio , Músculo Quadríceps/inervação , RNA Mensageiro/metabolismo , Fluxo Sanguíneo Regional , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Trocador de Sódio e Cálcio/genética
9.
Eur J Prev Cardiol ; 23(15): 1599-608, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27271264

RESUMO

BACKGROUND: We investigated the effects of muscle functional electrical stimulation on muscle sympathetic nerve activity and muscle blood flow, and, in addition, exercise tolerance in hospitalised patients for stabilisation of heart failure. METHODS: Thirty patients hospitalised for treatment of decompensated heart failure, class IV New York Heart Association and ejection fraction ≤ 30% were consecutively randomly assigned into two groups: functional electrical stimulation (n = 15; 54 ± 2 years) and control (n = 15; 49 ± 2 years). Muscle sympathetic nerve activity was directly recorded via microneurography and blood flow by venous occlusion plethysmography. Heart rate and blood pressure were evaluated on a beat-to-beat basis (Finometer), exercise tolerance by 6-minute walk test, quadriceps muscle strength by a dynamometer and quality of life by Minnesota questionnaire. Functional electrical stimulation consisted of stimulating the lower limbs at 10 Hz frequency, 150 ms pulse width and 70 mA intensity for 60 minutes/day for 8-10 consecutive days. The control group underwent electrical stimulation at an intensity of < 20 mA. RESULTS: Baseline characteristics were similar between groups, except age that was higher and C-reactive protein and forearm blood flow that were smaller in the functional electrical stimulation group. Functional electrical stimulation significantly decreased muscle sympathetic nerve activity and increased muscle blood flow and muscle strength. No changes were found in the control group. Walking distance and quality of life increased in both groups. However, these changes were greater in the functional electrical stimulation group. CONCLUSION: Functional electrical stimulation improves muscle sympathetic nerve activity and vasoconstriction and increases exercise tolerance, muscle strength and quality of life in hospitalised heart failure patients. These findings suggest that functional electrical stimulation may be useful to hospitalised patients with decompensated chronic heart failure.


Assuntos
Estimulação Elétrica/métodos , Tolerância ao Exercício/fisiologia , Insuficiência Cardíaca/terapia , Pacientes Internados , Força Muscular/fisiologia , Músculo Esquelético/fisiopatologia , Sistema Nervoso Simpático/fisiologia , Adolescente , Adulto , Idoso , Feminino , Antebraço/irrigação sanguínea , Insuficiência Cardíaca/fisiopatologia , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Pletismografia , Qualidade de Vida , Fluxo Sanguíneo Regional/fisiologia , Adulto Jovem
10.
Am J Physiol Heart Circ Physiol ; 308(9): H1096-102, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25747752

RESUMO

Arterial baroreflex control of muscle sympathetic nerve activity (ABRMSNA) is impaired in chronic systolic heart failure (CHF). The purpose of the study was to test the hypothesis that exercise training would improve the gain and reduce the time delay of ABRMSNA in CHF patients. Twenty-six CHF patients, New York Heart Association Functional Class II-III, EF ≤ 40%, peak V̇o2 ≤ 20 ml·kg(-1)·min(-1) were divided into two groups: untrained (UT, n = 13, 57 ± 3 years) and exercise trained (ET, n = 13, 49 ± 3 years). Muscle sympathetic nerve activity (MSNA) was directly recorded by microneurography technique. Arterial pressure was measured on a beat-to-beat basis. Time series of MSNA and systolic arterial pressure were analyzed by autoregressive spectral analysis. The gain and time delay of ABRMSNA was obtained by bivariate autoregressive analysis. Exercise training was performed on a cycle ergometer at moderate intensity, three 60-min sessions per week for 16 wk. Baseline MSNA, gain and time delay of ABRMSNA, and low frequency of MSNA (LFMSNA) to high-frequency ratio (HFMSNA) (LFMSNA/HFMSNA) were similar between groups. ET significantly decreased MSNA. MSNA was unchanged in the UT patients. The gain and time delay of ABRMSNA were unchanged in the ET patients. In contrast, the gain of ABRMSNA was significantly reduced [3.5 ± 0.7 vs. 1.8 ± 0.2, arbitrary units (au)/mmHg, P = 0.04] and the time delay of ABRMSNA was significantly increased (4.6 ± 0.8 vs. 7.9 ± 1.0 s, P = 0.05) in the UT patients. LFMSNA-to-HFMSNA ratio tended to be lower in the ET patients (P < 0.08). Exercise training prevents the deterioration of ABRMSNA in CHF patients.


Assuntos
Pressão Arterial , Barorreflexo , Sistema Cardiovascular/inervação , Terapia por Exercício , Insuficiência Cardíaca/terapia , Músculo Esquelético/inervação , Sistema Nervoso Simpático/fisiopatologia , Adulto , Idoso , Ciclismo , Brasil , Doença Crônica , Terapia por Exercício/métodos , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento
11.
Am J Physiol Heart Circ Physiol ; 308(8): H792-802, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25681428

RESUMO

Neurohormonal excitation and dyspnea are the hallmarks of heart failure (HF) and have long been associated with poor prognosis in HF patients. Sympathetic nerve activity (SNA) and ventilatory equivalent of carbon dioxide (VE/VO2) are elevated in moderate HF patients and increased even further in severe HF patients. The increase in SNA in HF patients is present regardless of age, sex, and etiology of systolic dysfunction. Neurohormonal activation is the major mediator of the peripheral vasoconstriction characteristic of HF patients. In addition, reduction in peripheral blood flow increases muscle inflammation, oxidative stress, and protein degradation, which is the essence of the skeletal myopathy and exercise intolerance in HF. Here we discuss the beneficial effects of exercise training on resting SNA in patients with systolic HF and its central and peripheral mechanisms of control. Furthermore, we discuss the exercise-mediated improvement in peripheral vasoconstriction in patients with HF. We will also focus on the effects of exercise training on ventilatory responses. Finally, we review the effects of exercise training on features of the skeletal myopathy in HF. In summary, exercise training plays an important role in HF, working synergistically with pharmacological therapies to ameliorate these abnormalities in clinical practice.


Assuntos
Terapia por Exercício , Insuficiência Cardíaca Sistólica/fisiopatologia , Músculo Esquelético/fisiopatologia , Vasoconstrição , Tolerância ao Exercício , Insuficiência Cardíaca Sistólica/terapia , Humanos , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/inervação , Ventilação Pulmonar
12.
Prog Cardiovasc Dis ; 57(4): 337-46, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25559061

RESUMO

Regular exercise and a physically active lifestyle have favorable effects on health. Several issues related to this theme are addressed in this report. A comment on the requirements of personalized exercise medicine and in-depth biological profiling along with the opportunities that they offer is presented. This is followed by a brief overview of the evidence for the contributions of genetic differences to the ability to benefit from regular exercise. Subsequently, studies showing that mutations in TP53 influence exercise capacity in mice and humans are succinctly described. The evidence for effects of exercise on endothelial function in health and disease also is covered. Finally, changes in cardiac and skeletal muscle in response to exercise and their implications for patients with cardiac disease are summarized. Innovative research strategies are needed to define the molecular mechanisms involved in adaptation to exercise and to translate them into useful clinical and public health applications.


Assuntos
Doenças Cardiovasculares , Terapia por Exercício/métodos , Tolerância ao Exercício/genética , Músculo Esquelético/fisiologia , Medicina de Precisão/métodos , Proteína Supressora de Tumor p53/genética , Adaptação Fisiológica/genética , Animais , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/fisiopatologia , Doenças Cardiovasculares/prevenção & controle , Exercício , Estudo de Associação Genômica Ampla , Humanos , Camundongos , Atividade Motora/fisiologia , Mutação
13.
Am J Physiol Heart Circ Physiol ; 307(11): H1655-66, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25305179

RESUMO

Previous studies have demonstrated that muscle mechanoreflex and metaboreflex controls are altered in heart failure (HF), which seems to be due to changes in cyclooxygenase (COX) pathway and changes in receptors on afferent neurons, including transient receptor potential vanilloid type-1 (TRPV1) and cannabinoid receptor type-1 (CB1). The purpose of the present study was to test the hypotheses: 1) exercise training (ET) alters the muscle metaboreflex and mechanoreflex control of muscle sympathetic nerve activity (MSNA) in HF patients. 2) The alteration in metaboreflex control is accompanied by increased expression of TRPV1 and CB1 receptors in skeletal muscle. 3) The alteration in mechanoreflex control is accompanied by COX-2 pathway in skeletal muscle. Thirty-four consecutive HF patients with ejection fractions <40% were randomized to untrained (n = 17; 54 ± 2 yr) or exercise-trained (n = 17; 56 ± 2 yr) groups. MSNA was recorded by microneurography. Mechanoreceptors were activated by passive exercise and metaboreceptors by postexercise circulatory arrest (PECA). COX-2 pathway, TRPV1, and CB1 receptors were measured in muscle biopsies. Following ET, resting MSNA was decreased compared with untrained group. During PECA (metaboreflex), MSNA responses were increased, which was accompanied by the expression of TRPV1 and CB1 receptors. During passive exercise (mechanoreflex), MSNA responses were decreased, which was accompanied by decreased expression of COX-2, prostaglandin-E2 receptor-4, and thromboxane-A2 receptor and by decreased in muscle inflammation, as indicated by increased miRNA-146 levels and the stable NF-κB/IκB-α ratio. In conclusion, ET alters muscle metaboreflex and mechanoreflex control of MSNA in HF patients. This alteration with ET is accompanied by alteration in TRPV1 and CB1 expression and COX-2 pathway and inflammation in skeletal muscle.


Assuntos
Terapia por Exercício , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/terapia , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiopatologia , Reflexo/fisiologia , Adulto , Idoso , Doença Crônica , Ciclo-Oxigenase 2/fisiologia , Teste de Esforço , Feminino , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Receptor CB1 de Canabinoide/biossíntese , Transdução de Sinais/fisiologia , Volume Sistólico/fisiologia , Sistema Nervoso Simpático/fisiopatologia , Canais de Cátion TRPV/biossíntese
14.
Eur J Prev Cardiol ; 19(4): 822-9, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21697210

RESUMO

BACKGROUND: Exercise training is a non-pharmacological strategy for treatment of heart failure. Exercise training improves functional capacity and quality of life in patients. Moreover, exercise training reduces muscle sympathetic nerve activity (MSNA) and peripheral vasoconstriction. However, most of these studies have been conducted in middle-aged patients. Thus, the effects of exercise training in older patients are much less understood. The present study was undertaken to investigate whether exercise training improves functional capacity, muscular sympathetic activation and muscular blood flow in older heart failure patients, as it does in middle-aged heart failure patients. DESIGN: Fifty-two consecutive outpatients with heart failure from the database of the Unit of Cardiovascular Rehabilitation and Physiology Exercise were divided by age (middle-aged, defined as 45-59 years, and older, defined as 60-75 years) and exercise status (trained and untrained). METHODS: MSNA was recorded directly from the peroneal nerve using the microneurography technique. Forearm blood flow (FBF) was measured by venous occlusion plethysmography. Functional capacity was evaluated by cardiopulmonary exercise test. RESULTS: Exercise training significantly and similarly increased FBF and peak VO(2) in middle-aged and older heart failure patients. In addition, exercise training significantly and similarly reduced MSNA and forearm vascular resistance in these patients. No significant changes were found in untrained patients. CONCLUSION: Exercise training improves neurovascular control and functional capacity in heart failure patients regardless of age.


Assuntos
Terapia por Exercício , Insuficiência Cardíaca/reabilitação , Hemodinâmica , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/inervação , Nervo Fibular/fisiopatologia , Adulto , Fatores Etários , Idoso , Brasil , Tolerância ao Exercício , Feminino , Antebraço , Insuficiência Cardíaca/fisiopatologia , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Consumo de Oxigênio , Pletismografia , Recuperação de Função Fisiológica , Fluxo Sanguíneo Regional , Resultado do Tratamento
16.
Eur J Heart Fail ; 12(1): 58-65, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20023046

RESUMO

AIMS: We compared the effects of exercise training on neurovascular control and functional capacity in men and women with chronic heart failure (HF). METHODS AND RESULTS: Forty consecutive HF outpatients from the Heart Institute, University of Sao Paulo, Brazil were divided into the following four groups matched by age: men exercise-trained (n = 12), men untrained (n = 10), women exercise-trained (n = 9), women untrained (n = 9). Maximal exercise capacity was determined from a maximal progressive exercise test on a cycle ergometer. Forearm blood flow was measured by venous occlusion plethysmography. Muscle sympathetic nerve activity (MSNA) was recorded directly using the technique of microneurography. There were no differences between groups in any baseline parameters. Exercise training produced a similar reduction in resting MSNA (P = 0.000002) and forearm vascular resistance (P = 0.0003), in men and women with HF. Peak VO(2) was similarly increased in men and women with HF (P = 0.0003) and VE/VCO(2) slope was significantly decreased in men and women with HF (P = 0.0007). There were no significant changes in left-ventricular ejection fraction in men and women with HF. CONCLUSION: The benefits of exercise training on neurovascular control and functional capacity in patients with HF are independent of gender.


Assuntos
Exercício/fisiologia , Insuficiência Cardíaca/fisiopatologia , Músculo Esquelético/irrigação sanguínea , Sistema Nervoso Simpático/fisiologia , Adulto , Idoso , Pressão Sanguínea/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional , Fatores Sexuais , Volume Sistólico/fisiologia , Sistema Nervoso Simpático/fisiopatologia , Resultado do Tratamento
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