RESUMO
We aimed to analyse cardiac autonomic control by assessing the post-exercise heart rate recovery (HRR) and physical fitness in children and adolescents with spina bifida (SB), compared to participants with typical development. A total of 124 participants, 42 with spina bifida (SB group) and 82 typical developmental controls (CO group) performed the arm cranking exercise test with a gas analysis system. HRR was determined at the first (HRR_1) and second (HRR_2) minute at recovery phase. Data are shown as [mean difference (95% CI)]. The SB group showed reduced HR reserve [14.5 (7.1-22.0) bmp, P<0.01], slower HRR_1 [12.4 (7.4-17.5) bpm, P<0.01] and HRR_2 [16.3 (10.6-21.9) bpm; P<0.01], lower VO2peak [VO2peak relative: 7.3 (4.2-10.3) mL·min-1·kg-1, P<0.01; VO2peak absolute: 0.42 (0.30-0.54) L·min-1, P<0.01], and lower O2 pulse [2.5 (1.8-3.2) mL·bpm, P<0.01] and ventilatory responses [13.5 (8.8-18.1) L·min-1, P<0.01] than the CO group. VE/VO2 was not different between groups [-2.82 (-5.77- -0.12); P=0.06], but the VE/VCO2 [-2.59 (-4.40-0.78); P<0.01] and the values of the anaerobic threshold corrected by body mass [-3.2 (-5.8- -0.6) mL·min-1·kg-1, P=0.01] were higher in the SB group than in the CO group. We concluded that children and adolescents with SB have reduced physical fitness and a slower HRR response after maximal effort.
Assuntos
Frequência Cardíaca/fisiologia , Consumo de Oxigênio/fisiologia , Aptidão Física/fisiologia , Disrafismo Espinal/fisiopatologia , Adolescente , Criança , Teste de Esforço , Feminino , Humanos , MasculinoRESUMO
PURPOSE: We analyzed the evolution and pattern of heart rate (HR) during the 12-minute wheelchair propulsion field test (WPFT) and compared the peak HR (HRpeak) from the WPFT to the HRpeak obtained in the progressive cardiopulmonary exercise test on arm cranking ergometer (ACT). We aimed to determine if the field test detects the HRpeak consistently and could be used in clinical practice. METHODS: Eleven wheelchair-using children and adolescents with myelomeningocele (aged 8-15 y) performed a maximal ACT and a 12-minute WPFT. HR was recorded continuously at rest, during each minute of the tests, and at recovery. Mixed analysis of variance was used to compare the variables at rest and peak. Bland-Altman plot and Lin's concordance correlation coefficient were used to show agreement between the tests. RESULTS: During minute 2 of the WPFT, participants reached 73%-96% of the HRpeak values recorded in the ACT. From minutes 4 to 12, participants reached HRpeak values ranging 86%-109% of the values recorded in the ACT. There is agreement between the ACT and the WPFT tests. CONCLUSION: WPFT with minimal duration of 4 minutes may be an alternative tool to obtain HRpeak in children and adolescents with myelomeningocele.
Assuntos
Frequência Cardíaca , Meningomielocele/fisiopatologia , Cadeiras de Rodas , Adolescente , Criança , Ergometria , Teste de Esforço , Feminino , Humanos , MasculinoRESUMO
BACKGROUND: Primary microvascular angina (PMA) is a common clinical condition associated to negative impact on quality of life (QOL) and reduced physical capacity. This study aimed at evaluating the effects of aerobic physical training (APT) on myocardial perfusion, physical capacity, and QOL in patients with PMA. METHODS: We investigated 12 patients (53.8 ± 9.7 years old; 7 women) with PMA, characterized by angina, angiographycally normal coronary arteries, and reversible perfusion defects (RPDs) detected on (99m)Tc-sestamibi-SPECT myocardial perfusion scintigraphy (MPS). At baseline and after 4 month of APT, the patients underwent MPS, cardiopulmonary test, and QOL questionnaire. Stress-rest MPS images were visually analyzed by attributing semi-quantitative scores (0 = normal; 4 = absent uptake), using a 17-segment left ventricular model. Summed stress, rest, and difference scores (SDS) were calculated. RESULTS: In comparison to the baseline, in the post-training we observed a significant increase in peak-VO2 (19.4 ± 4.8 and 22.1 ± 6.2 mL·kg(-1)·minute(-1), respectively, P = .01), reduction of SDS (10.1 ± 8.8 and 2.8 ± 4.9, P = .008), and improvement in QOL scores. CONCLUSIONS: Physical training in patients with PMA is associated with reduction of myocardial perfusion abnormalities, increasing of physical capacity, and improvement in QOL. The findings of this hypothesis-generating study suggest that APT can be a valid therapeutic option for patients with PMA.
Assuntos
Angina Microvascular/diagnóstico por imagem , Angina Microvascular/psicologia , Imagem de Perfusão do Miocárdio , Idoso , Exercício Físico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Qualidade de Vida , Cintilografia , Compostos Radiofarmacêuticos , Inquéritos e Questionários , Tecnécio Tc 99m Sestamibi , Tomografia Computadorizada de Emissão de Fóton Único , Disfunção Ventricular Esquerda/diagnóstico por imagemRESUMO
INTRODUCTION: Chronic Chagas cardiomyopathy (CCC), the most severe clinical condition of Chagas disease, often leads to a reduction in functional capacity and the appearance of symptoms such as fatigue and dyspnea on exertion. However, its determinant factors remain unclear. We aimed to evaluate the peak oxygen consumption (VO2peak) in patients with CCC and identify its determining factors. METHODS: An observational study with 97 CCC patients was conducted. Patients underwent clinical examination, cardiopulmonary exercise test (CPET), and echocardiography as part of the standard clinical evaluation. Multivariate linear regression was used to identify independent clinical and echocardiographic predictors of VO2peak and percentage of predicted VO2. RESULTS: Mean age of study patients was 55.9⯱â¯13.4â¯years, median left ventricle ejection fraction (LVEF) was 40 (26-61.5) % and median VO2peak was 16.1 (12.1-20.8) ml/Kg/min. 36 patients presented preserved LVEF and 61 presented reduced LVEF. There were significant differences in almost all CPET variables (pâ¯<â¯0.05) between these two groups. VO2peak was associated with age, male sex, NYHA functional class, LVEF, left atrium diameter, LV diastolic diameter, E wave, LV mass index, and pulmonary artery systolic pressure (PASP). Age, male sex, LVEF, and E wave remained independently associated with VO2peak in the multivariate analysis (R2â¯=â¯0.69), furthermore, only LVEF and E wave were associated with the predicted VO2 percentage (R2â¯=â¯0.53). CONCLUSION: In patients with CCC, disease severity, male sex, LV systolic and diastolic function influence the functional capacity.
RESUMO
Rheumatic mitral stenosis (RMS) is still a significant public health problem in low- and middle-income countries. Pulmonary hypertension (PH) is a common consequence of RMS and may be used as a surrogate of disease severity. Cardiopulmonary exercise testing (CPET) provides a comprehensive assessment of the cardiorespiratory systems and can identify indirect signs of PH. To evaluate the relationship between CPET parameters and PH quantified by echocardiography in patients with RMS. This cross-sectional study retrospectively included thirty patients with RMS referred for CPET from 2012 to 2020. Two groups of patients were defined according to echocardiographic-derived pulmonary systolic arterial pressure (PASP): significant PH group (PSAP ≥ 50 mmHg); and non-significant PH group (PSAP < 50 mmHg). A decrease in peak oxygen consumption (VO2) and oxygen pulse predicted (O2PP) was observed in the PH group compared to the non-significant PH group (11.1±2.8 mL/kg/min vs 14.1±2.9 mL/kg/min; Pâ¯=â¯0.02; 54±9% vs 67.8±15%; Pâ¯=â¯0.02). The PH group exhibited a greater VE/VCO2 nadir rather than non-significant PH group (38±5 vs 32±3; P < 0.001). Receiver operating characteristic (ROC) analysis with O2PP <54% showed sensitivity and specificity of 67% and 90%, respectively. VE/VCO2 nadir ≥ 40 and VO2 peak < 10.8 mL/kg/min showed 44% and 56% of sensitivity and 100% and 90% of specificity respectively. CPET can improve the assessment of disease severity in patients with RMS with high specificity. The presence of higher O2PP, higher VO2 peak, and lower VE/VCO2 nadir highly suggests the absence of significant PH.
Assuntos
Hipertensão Pulmonar , Estenose da Valva Mitral , Humanos , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/etiologia , Teste de Esforço , Valva Mitral/diagnóstico por imagem , Estudos Retrospectivos , Estudos Transversais , Ecocardiografia , Estenose da Valva Mitral/complicações , Estenose da Valva Mitral/diagnósticoRESUMO
Heart Rate Variability (HRV) and arterial pressure (AP) variability and their responses to head-up tilt test (HUTT) were investigated in Post-COVID-19 syndrome (PCS) patients reporting tachycardia and/or postural hypotension. Besides tachycardia, PCS patients also showed attenuation of the following HRV parameters: RMSSD [square root of the mean of the sum of the squares of differences between adjacent normal-to-normal (NN) intervals] from statistical measures; the power of RR (beat-to-beat interval) spectra at HF (high frequency) from the linear method spectral analysis; occurrence of 2UV (two unlike variation) pattern of RR from the nonlinear method symbolic analysis; and the new family of statistics named sample entropy, when compared to control subjects. Basal AP and LF (low frequency) power of systolic AP were similar between PCS patients and control subjects, while 0 V (zero variation) patterns of AP from the nonlinear method symbolic analysis were exacerbated in PCS patients. Despite tachycardia and a decrease in RMSSD, no parameter of HRV changed during HUTT in PCS patients compared to control subjects. PCS patients reassessed after 6 months showed higher HF power of RR spectra and a higher percentage of 2UV pattern of RR. Moreover, the reassessed PCS patients showed a lower occurrence of 0 V patterns of AP, while the HUTT elicited HR (heart rate) and AP responses identical to control subjects. The HRV and AP variability suggest an autonomic dysfunction with sympathetic predominance in PCS patients. In contrast, the lack of responses of HRV and AP variability indices during HUTT indicates a marked impairment of autonomic control. Of note, the reassessment of PCS patients showed that the noxious effect of COVID-19 on autonomic control tended to fade over time.
RESUMO
BACKGROUND: Maintenance of orthostatism requires the interaction of autonomic and muscle responses for an efficient postural control, to minimize body motion and facilitate venous return in a common type of syncope called neurocardiogenic syncope (NCS). Muscle activity in standing position may be registered by surface electromyography, and body sway confirmed by displacement of the center of pressure (COP) on a force platform. These peripheral variables reflect the role of muscles in the maintenance of orthostatism during the active tilt test, which, compared with muscle activity during the passive test (head-up tilt test), enables the analyses of electromyographic activity of these muscles that may anticipate the clinical effects of CNS during these tests. OBJECTIVE: to evaluate and compare the effects of a standardized protocol of active and passive tests for CNS diagnosis associated with the effects of Valsalva maneuver (VM). METHODS: twenty-thee clinically stable female volunteers were recruited to undergo both tests. EMG electrodes were placed on muscles involved in postural maintenance. During the active test, subjects stood on a force platform. In addition to electromyography and the platform, heart rate was recorded during all tests. Three VMs were performed during the tests. RESULTS: progressive peripheral changes were observed along both tests, more evidently during the active test. CONCLUSION: the active test detected changes in muscle and cardiovascular responses, which were exacerbated by the VM.
Assuntos
Frequência Cardíaca/fisiologia , Músculo Esquelético/fisiologia , Teste da Mesa Inclinada/métodos , Adolescente , Adulto , Eletromiografia , Feminino , Humanos , Postura , Adulto JovemRESUMO
The study of myocardial contractility, based on the new anatomical concepts that govern cardiac mechanics, represents a promising strategy of analysis of myocardial adaptations related to physical training in the context of post-infarction. We investigated the influence of aerobic training on physical capacity and on the evaluation parameters of left ventricular contraction mechanics in patients with myocardial infarction. Thirty-one patients (55.1 ± 8.9 years) who had myocardial infarction in the anterior wall were prospectively investigated in three groups: interval training group (ITG) (n = 10), moderate training group (MTG) n = 10) and control group (CG) (n = 10). Before and after 12 weeks of clinical follow-up, patients underwent cardiopulmonary exercise testing and cardiac magnetic resonance imaging. The trained groups performed supervised aerobic training on treadmill, in two different intensities. A statistically significant increase in peak oxygen uptake (VO2) was observed in the ITG (19.2 ± 5.1 at 21.9 ± 5.6 ml/kg/min, p < 0.01) and in the MTG 18.8 ± 3.7 to 21.6 ± 4.5 ml/kg/min, p < 0.01). The GC did not present a statistically significant change in peak VO2. A statistically significant increase in radial strain (STRAD) was observed in the CG: basal STRAD (57.4 ± 16.6 to 84.1 ± 30.9%, p < 0.05), medial STRAD (57.8 ± 27, 9 to 74.3 ± 36.1%, p < 0.05) and apical STRAD (38.2 ± 26.0 to 52.4 ± 29.8%, p < 0.01). The trained groups did not present a statistically significant change of the radial strain. The present study points to a potential clinical application of the parameters of ventricular contraction mechanics analysis, especially radial strain, to discriminate post-infarction myocardial adaptations between patients submitted or not to aerobic training programs.
Assuntos
Terapia por Exercício/métodos , Exercício Físico/fisiologia , Contração Miocárdica/fisiologia , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/reabilitação , Função Ventricular Esquerda/fisiologia , Pressão Sanguínea/fisiologia , Teste de Esforço/métodos , Frequência Cardíaca/fisiologia , Ventrículos do Coração/fisiopatologia , Humanos , Pessoa de Meia-Idade , Consumo de Oxigênio/fisiologia , Projetos Piloto , Estudos Prospectivos , Reprodutibilidade dos Testes , Estatísticas não Paramétricas , Fatores de Tempo , Resultado do TratamentoRESUMO
BACKGROUND: Numerous studies show the benefits of exercise training after myocardial infarction (MI). Nevertheless, the effects on function and remodeling are still controversial. OBJECTIVES: To evaluate, in patients after (MI), the effects of aerobic exercise of moderate intensity on ventricular remodeling by cardiac magnetic resonance imaging (CMR). METHODS: 26 male patients, 52.9 ± 7.9 years, after a first MI, were assigned to groups: trained group (TG), 18; and control group (CG), 8. The TG performed supervised aerobic exercise on treadmill twice a week, and unsupervised sessions on 2 additional days per week, for at least 3 months. Laboratory tests, anthropometric measurements, resting heart rate (HR), exercise test, and CMR were conducted at baseline and follow-up. RESULTS: The TG showed a 10.8% reduction in fasting blood glucose (p = 0.01), and a 7.3-bpm reduction in resting HR in both sitting and supine positions (p < 0.0001). There was an increase in oxygen uptake only in the TG (35.4 ± 8.1 to 49.1 ± 9.6 mL/kg/min, p < 0.0001). There was a statistically significant decrease in the TG left ventricular mass (LVmass) (128.7 ± 38.9 to 117.2 ± 27.2 g, p = 0.0032). There were no statistically significant changes in the values of left ventricular end-diastolic volume (LVEDV) and ejection fraction in the groups. The LVmass/EDV ratio demonstrated a statistically significant positive remodeling in the TG (p = 0.015). CONCLUSIONS: Aerobic exercise of moderate intensity improved physical capacity and other cardiovascular variables. A positive remodeling was identified in the TG, where a left ventricular diastolic dimension increase was associated with LVmass reduction.
Assuntos
Terapia por Exercício/métodos , Exercício Físico/fisiologia , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/reabilitação , Remodelação Ventricular/fisiologia , Adulto , Índice de Massa Corporal , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Teste de Esforço , Frequência Cardíaca/fisiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico por imagem , Valores de Referência , Reprodutibilidade dos Testes , Estatísticas não Paramétricas , Volume Sistólico/fisiologia , Fatores de Tempo , Resultado do Tratamento , Triglicerídeos/sangue , Função Ventricular Esquerda/fisiologiaAssuntos
Reabilitação Cardíaca , Jogos de Vídeo , Exercício Físico , Terapia por Exercício , HumanosRESUMO
BACKGROUND: Characterized as a sudden and temporary loss of consciousness and postural tone, with quick and spontaneous recovery, syncope is caused by an acute reduction of systemic arterial pressure and, therefore, of cerebral blood flow. Unsatisfactory results with the use of drugs allowed the nonpharmacological treatment of neurocardiogenic syncope was contemplated as the first therapeutic option. OBJECTIVES: To compare, in patients with neurocardiogenic syncope, the impact of a moderate intensity aerobic physical training (AFT) and a control intervention on the positivity of head-up tilting test (HUT) and orthostatic tolerance time. METHODS: Were studied 21 patients with a history of recurrent neurocardiogenic syncope and HUT. The patients were randomized into: trained group (TG), n = 11, and control group (CG), n = 10. The TG was submitted to 12 weeks of AFT supervised, in cycle ergometer, and the CG to a control procedure that consisted in 15 minutes of stretching and 15 minutes of light walk. RESULTS: The TG had a positive effect to physical training, with a significant increase in peak oxygen consumption. The CG did not show any statistically significant change before and after the intervention. After the intervention period, 72.7% of the TG sample had negative results to the HUT, not having syncope in the revaluation. CONCLUSION: The program of supervised aerobic physical training for 12 weeks was able to reduce the number of positive HUT, as it was able to increase tolerance time in orthostatic position during the HUT after the intervention period.
Assuntos
Teste de Esforço/métodos , Terapia por Exercício/métodos , Tolerância ao Exercício/fisiologia , Síncope Vasovagal/terapia , Adolescente , Adulto , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Valores de Referência , Teste da Mesa Inclinada , Fatores de Tempo , Resultado do Tratamento , Adulto JovemRESUMO
Abstract Background: Maintenance of orthostatism requires the interaction of autonomic and muscle responses for an efficient postural control, to minimize body motion and facilitate venous return in a common type of syncope called neurocardiogenic syncope (NCS). Muscle activity in standing position may be registered by surface electromyography, and body sway confirmed by displacement of the center of pressure (COP) on a force platform. These peripheral variables reflect the role of muscles in the maintenance of orthostatism during the active tilt test, which, compared with muscle activity during the passive test (head-up tilt test), enables the analyses of electromyographic activity of these muscles that may anticipate the clinical effects of CNS during these tests. Objective: to evaluate and compare the effects of a standardized protocol of active and passive tests for CNS diagnosis associated with the effects of Valsalva maneuver (VM). Methods: twenty-thee clinically stable female volunteers were recruited to undergo both tests. EMG electrodes were placed on muscles involved in postural maintenance. During the active test, subjects stood on a force platform. In addition to electromyography and the platform, heart rate was recorded during all tests. Three VMs were performed during the tests. Results: progressive peripheral changes were observed along both tests, more evidently during the active test. Conclusion: the active test detected changes in muscle and cardiovascular responses, which were exacerbated by the VM.
Resumo Fundamento: A manutenção do ortostatismo requer interação das respostas autonômicas e musculares para um controle postural eficiente e minimizar oscilações do corpo e facilitar o retorno venoso frente a um tipo comum de síncope chamada neurocardiogênica (SNC). A atividade da musculatura na posição de pé pode ser documentada por meio da eletromiografia de superfície (EMG) e as oscilações do corpo confirmadas pelo deslocamento do centro de pressão (CP) sobre uma plataforma de força. Estas variáveis periféricas mostram o papel muscular na manutenção do ortostatismo durante o tilt test ativo bem como esta atividade muscular ser comparada durante o teste passivo, Head-Up Tilt test, na tentativa de verificar alterações na atividade eletromiográfica destes músculos que podem antecipar os efeitos clínicos da SNC durante estes testes. Objetivo: Avaliar e comparar os efeitos de um protocolo padronizado para testes ativo e passivo de detecção da SNC associado ao efeito da manobra de valsalva (MV). Métodos: 23 voluntárias mulheres clinicamente saudáveis foram recrutadas para realizar ambos os testes. Os eletrodos da EMG foram posicionados em músculos associados com a manutenção postural, além de durante o teste ativo os sujeitos realizarem a postura ortostática sobre uma plataforma de força. Foi registrado além da EMG e da plataforma, a frequência cardíaca durante todo o teste. Três MV foram realizadas durante os testes. Resultados: Alterações periféricas foram verificadas de maneira progressiva ao longo dos testes, sendo mais evidente durante o teste ativo. Conclusão: o teste ativo verificou mudanças mais evidentes nas respostas musculares e cardiovasculares, amplificadas pela MV.
Assuntos
Humanos , Feminino , Adolescente , Adulto , Adulto Jovem , Teste da Mesa Inclinada/métodos , Músculo Esquelético/fisiologia , Frequência Cardíaca/fisiologia , Postura , EletromiografiaRESUMO
Chronic aortic regurgitation (AR) is a valvulopathy of slow and insidious evolution, and patients may remain asymptomatic for a long period of time. Exercise-induced systolic dysfunction occurs during the natural history of chronic AR and is related to changes in both preload and afterload. We describe the case of a 58-year-old woman with a diagnosis of chronic AR who reported progressive dyspnea of six years' duration. A cardiopulmonary exercise test to assess functional capacity showed flattening of both oxygen uptake and oxygen pulse curves, suggesting latent systolic dysfunction related to chronic AR, which was later confirmed by stress Doppler echocardiogram with dynamic physical exercise.
Assuntos
Insuficiência da Valva Aórtica/complicações , Teste de Esforço , Disfunção Ventricular Esquerda/diagnóstico , Disfunção Ventricular Esquerda/etiologia , Doença Crônica , Feminino , Humanos , Pessoa de Meia-Idade , SístoleRESUMO
Abstract The study of myocardial contractility, based on the new anatomical concepts that govern cardiac mechanics, represents a promising strategy of analysis of myocardial adaptations related to physical training in the context of post-infarction. We investigated the influence of aerobic training on physical capacity and on the evaluation parameters of left ventricular contraction mechanics in patients with myocardial infarction. Thirty-one patients (55.1 ± 8.9 years) who had myocardial infarction in the anterior wall were prospectively investigated in three groups: interval training group (ITG) (n = 10), moderate training group (MTG) n = 10) and control group (CG) (n = 10). Before and after 12 weeks of clinical follow-up, patients underwent cardiopulmonary exercise testing and cardiac magnetic resonance imaging. The trained groups performed supervised aerobic training on treadmill, in two different intensities. A statistically significant increase in peak oxygen uptake (VO2) was observed in the ITG (19.2 ± 5.1 at 21.9 ± 5.6 ml/kg/min, p < 0.01) and in the MTG 18.8 ± 3.7 to 21.6 ± 4.5 ml/kg/min, p < 0.01). The GC did not present a statistically significant change in peak VO2. A statistically significant increase in radial strain (STRAD) was observed in the CG: basal STRAD (57.4 ± 16.6 to 84.1 ± 30.9%, p < 0.05), medial STRAD (57.8 ± 27, 9 to 74.3 ± 36.1%, p < 0.05) and apical STRAD (38.2 ± 26.0 to 52.4 ± 29.8%, p < 0.01). The trained groups did not present a statistically significant change of the radial strain. The present study points to a potential clinical application of the parameters of ventricular contraction mechanics analysis, especially radial strain, to discriminate post-infarction myocardial adaptations between patients submitted or not to aerobic training programs.
Resumo O estudo da contratilidade miocárdica, baseado nos novos conceitos anatômicos que regem a mecânica cardíaca, representa uma estratégia promissora de análise das adaptações do miocárdio relacionadas ao treinamento físico no contexto do pós-infarto. Nós investigamos a influência do treinamento aeróbico na capacidade física e nos parâmetros de avaliação da mecânica de contração do ventrículo esquerdo em pacientes com infarto do miocárdio. Foram prospectivamente investigados 30 pacientes, 55,1 ± 8,9 anos, acometidos por infarto do miocárdio de parede anterior, aleatorizados em três grupos: grupo treinamento intervalado (GTI) (n = 10), grupo treinamento moderado (GTM) (n=10) e grupo controle (GC) (n = 10). Antes e após as 12 semanas de seguimento clínico, os pacientes realizaram teste cardiopulmonar de exercício e ressonância magnética cardíaca. Os grupos treinados realizaram treinamento aeróbico supervisionado, em esteira ergométrica, aplicando-se duas intensidades distintas. Observou-se aumento estatisticamente significante do consumo de oxigênio (VO2) pico no GTI (19,2 ± 5,1 para 21,9 ± 5,6 ml/kg/min, p < 0,01) e no GTM (18,8 ± 3,7 para 21,6 ± 4,5 ml/kg/min, p < 0,01). O GC não apresentou mudança estatisticamente significante no VO2 pico. Houve aumento estatisticamente significante do strain radial (STRAD) somente no GC: STRAD basal (57,4 ± 16,6 para 84,1 ± 30,9%, p < 0,05), STRAD medial (57,8 ± 27,9 para 74,3 ± 36,1%, p < 0,05) e STRAD apical (38,2 ± 26,0 para 52,4 ± 29,8%, p < 0,01). Os grupos treinados não apresentaram mudança estatisticamente significante do strain radial. Os achados do presente estudo apontam para uma potencial aplicação clínica dos parâmetros de análise da mecânica de contração ventricular, notadamente do strain radial, em discriminar adaptações do miocárdio pós-infarto entre pacientes submetidos ou não a programas de treinamento aeróbico.
Assuntos
Humanos , Pessoa de Meia-Idade , Exercício Físico/fisiologia , Função Ventricular Esquerda/fisiologia , Terapia por Exercício/métodos , Contração Miocárdica/fisiologia , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/reabilitação , Consumo de Oxigênio/fisiologia , Fatores de Tempo , Pressão Sanguínea/fisiologia , Projetos Piloto , Estudos Prospectivos , Reprodutibilidade dos Testes , Resultado do Tratamento , Estatísticas não Paramétricas , Teste de Esforço/métodos , Frequência Cardíaca/fisiologia , Ventrículos do Coração/fisiopatologiaRESUMO
OBJECTIVE: The potential influence of magnesium on exercise performance is a subject of increasing interest. Magnesium has been shown to have bronchodilatatory properties in asthma and chronic obstructive pulmonary disease patients. The aim of this study was to investigate the effects of acute magnesium IV loading on the aerobic exercise performance of stable chronic obstructive pulmonary disease patients. METHODS: Twenty male chronic obstructive pulmonary disease patients (66.2 + 8.3 years old, FEV1: 49.3+19.8%) received an IV infusion of 2 g of either magnesium sulfate or saline on two randomly assigned occasions approximately two days apart. Spirometry was performed both before and 45 minutes after the infusions. A symptom-limited incremental maximal cardiopulmonary test was performed on a cycle ergometer at approximately 100 minutes after the end of the infusion. RESULTS: Magnesium infusion was associated with significant reductions in the functional residual capacity (-0.41 l) and residual volume (-0.47 l), the mean arterial blood pressure (-5.6 mmHg) and the cardiac double product (734.8 mmHg.bpm) at rest. Magnesium treatment led to significant increases in the maximal load reached (+8 w) and the respiratory exchange ratio (0.06) at peak exercise. The subgroup of patients who showed increases in the work load equal to or greater than 5 w also exhibited significantly greater improvements in inspiratory capacity (0.29 l). CONCLUSIONS: The acute IV loading of magnesium promotes a reduction in static lung hyperinflation and improves the exercise performance in stable chronic obstructive pulmonary disease patients. Improvements in respiratory mechanics appear to be responsible for the latter finding.
Assuntos
Teste de Esforço/efeitos dos fármacos , Magnésio/administração & dosagem , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Idoso , Broncodilatadores/administração & dosagem , Exercício Físico/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio/efeitos dos fármacos , Testes de Função Respiratória , Volume de Ventilação Pulmonar/efeitos dos fármacos , Resultado do Tratamento , Sinais Vitais/efeitos dos fármacosRESUMO
The objective of this report is to document the effects of an aerobic training program on myocardial perfusion, and endothelial function abnormalities, and on the relief of angina in a patient with microvascular myocardial ischemia. A 53-year-old female patient exhibited precordial pain on effort and angiographically normal coronaries. Her symptoms had been present for 4 yrs despite pharmacologic treatment for the control of risk factors, with myocardial perfusion scintigraphy revealing an extensive reversible perfusion defect. She was submitted to aerobic training for 4 mos, obtaining significant improvement of the anginal symptoms. Additionally, after the aerobic training program, scintigraphy revealed the disappearance of the myocardial perfusion defect, with a marked improvement of endothelium-dependent vasodilatory response and an improved quality-of-life score. These results suggest that aerobic training can improve endothelial function, leading to a reduction of ischemia and an improved quality-of-life in patients with microvascular myocardial ischemia.
Assuntos
Endotélio Vascular/fisiopatologia , Exercício Físico , Isquemia Miocárdica/reabilitação , Imagem de Perfusão do Miocárdio , Feminino , Humanos , Angina Microvascular/diagnóstico , Angina Microvascular/reabilitação , Pessoa de Meia-Idade , Isquemia Miocárdica/fisiopatologia , Qualidade de Vida , Tomografia Computadorizada de Emissão de Fóton ÚnicoRESUMO
Abstract Background: Numerous studies show the benefits of exercise training after myocardial infarction (MI). Nevertheless, the effects on function and remodeling are still controversial. Objectives: To evaluate, in patients after (MI), the effects of aerobic exercise of moderate intensity on ventricular remodeling by cardiac magnetic resonance imaging (CMR). Methods: 26 male patients, 52.9 ± 7.9 years, after a first MI, were assigned to groups: trained group (TG), 18; and control group (CG), 8. The TG performed supervised aerobic exercise on treadmill twice a week, and unsupervised sessions on 2 additional days per week, for at least 3 months. Laboratory tests, anthropometric measurements, resting heart rate (HR), exercise test, and CMR were conducted at baseline and follow-up. Results: The TG showed a 10.8% reduction in fasting blood glucose (p = 0.01), and a 7.3-bpm reduction in resting HR in both sitting and supine positions (p < 0.0001). There was an increase in oxygen uptake only in the TG (35.4 ± 8.1 to 49.1 ± 9.6 mL/kg/min, p < 0.0001). There was a statistically significant decrease in the TG left ventricular mass (LVmass) (128.7 ± 38.9 to 117.2 ± 27.2 g, p = 0.0032). There were no statistically significant changes in the values of left ventricular end-diastolic volume (LVEDV) and ejection fraction in the groups. The LVmass/EDV ratio demonstrated a statistically significant positive remodeling in the TG (p = 0.015). Conclusions: Aerobic exercise of moderate intensity improved physical capacity and other cardiovascular variables. A positive remodeling was identified in the TG, where a left ventricular diastolic dimension increase was associated with LVmass reduction.
Resumo Fundamento: Vários estudos mostraram os benefícios da prática de exercício após infarto do miocárdio (IM). No entanto, os efeitos na função e no remodelamento são controversos. Objetivos: Avaliar os efeitos do exercício aeróbio de intensidade moderada no remodelamento ventricular em pacientes após IM através de ressonância magnética cardíaca (RMC). Métodos: 26 pacientes do sexo masculino (52,9 ± 7,9 anos), após um primeiro IM, foram designados para dois grupos: grupo treinado (GT), 18; e grupo controle (GC), 8. O GT realizou exercício aeróbio supervisionado em esteira duas vezes por semana, e não supervisionado em 2 dias adicionais por semana, por no mínimo 3 meses. Exames laboratoriais, medidas antropométricas, frequência cardíaca (FC) de repouso, teste de esforço e RMC foram realizados na condição basal e no seguimento. Resultados: O GT apresentou redução de 10,8% na glicemia de jejum (p = 0,01), e de 7,3 bpm na FC de repouso nas posições sentada e supina (p < 0,0001). Houve aumento no consumo de oxigênio apenas no GT (de 35,4 ± 8,1 para 49,1 ± 9,6 ml/kg/min, p < 0,0001) e diminuição estatisticamente significativa na massa ventricular esquerda (MVE) no GT (de 128,7 ± 38,9 para 117,2 ± 27,2 g, p = 0,0032). Não houve alterações estatisticamente significativas no volume diastólico final ventricular esquerdo (VDFVE) nem na fração de ejeção nos grupos. A relação MVE/VDFVE demonstrou remodelamento positivo estatisticamente significativo no GT (p = 0,015). Conclusões: Observou-se remodelamento positivo no GT, onde o aumento da dimensão diastólica ventricular esquerda associou-se com redução da MVE. O exercício aeróbio de intensidade moderada melhorou a capacidade física e outras variáveis cardiovasculares.
Assuntos
Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Exercício Físico/fisiologia , Remodelação Ventricular/fisiologia , Terapia por Exercício/métodos , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/reabilitação , Valores de Referência , Volume Sistólico/fisiologia , Fatores de Tempo , Triglicerídeos/sangue , Imageamento por Ressonância Magnética , Índice de Massa Corporal , Reprodutibilidade dos Testes , Função Ventricular Esquerda/fisiologia , Resultado do Tratamento , Estatísticas não Paramétricas , Teste de Esforço , Frequência Cardíaca/fisiologia , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Infarto do Miocárdio/diagnóstico por imagemRESUMO
BACKGROUND: Chronic heart failure (HF) is a syndrome characterized by reduced cardiac output in relation to the metabolic needs of the organism, as well as metabolic and neurohormonal axis abnormalities. Symptoms such as fatigue and dyspnoea are notorious and stress tests are widely used to assess functional capacity, prognosis and effectiveness of therapeutic interventions in this syndrome. OBJECTIVE: To evaluate the reproducibility of the six-minute walk test (6MW) in patients with HF and correlate the magnitude of the variables reached at peak exercise of the 6MWT with a cardiopulmonary exercise test (CPET). METHODS: We studied 16 patients (12 men and 4 women) diagnosed with HF FC I-II (NYHA). The volunteers underwent two 6MWT (6MWT'1 and 6MWT'2) with 30-minute interval between them; then, they underwent a maximum CPET. RESULTS: All variables obtained in the two 6MWT' proved to be significant with high correlations: distance walked (DW) (r = 0.93, p < 0.0001), heart rate (HR) (r = 0.89, p < 0.0001), oxygen consumption (VO2) (r = 0.93, p < 0.0001) and scale of perceived exertion (r = 0.85, p < 0.0001). In turn, all variables analyzed in the 6MWT' showed significant and moderate correlations with the variables obtained from the CPET, namely: peak HR (r = 0.66; p = 0.005); VO2 (r = 0.57; p = 0.02) and VO2 in the CPET and DT in the 6MWT'2 (r = 0.70; p = 0.002). CONCLUSION: The 6MWT was reproducible in this group of patients with HF (NYHA - I-II) and correlated with the CPET. Therefore, it is a tool for reliable evaluation, and a suitable, safe and low-cost alternative for the prescription of aerobic exercise in patients with HF.
Assuntos
Teste de Esforço , Insuficiência Cardíaca/fisiopatologia , Idoso , Tolerância ao Exercício/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Consumo de Oxigênio/fisiologia , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Testes de Função Respiratória , Estatísticas não Paramétricas , Fatores de Tempo , Caminhada/fisiologiaRESUMO
Fundamento: Caracterizada por perda súbita e transitória da consciência e do tônus postural, com recuperação rápida e espontânea, a síncope é causada por uma redução aguda da pressão arterial sistêmica e, por conseguinte, do fluxo sanguíneo cerebral. Os resultados insatisfatórios com o uso de fármacos permitiu que o tratamento não farmacológico da síncope neurocardiogênica fosse contemplado como primeira opção terapêutica. Objetivos: Comparar, em pacientes com síncope neurocardiogênica, o impacto do Treinamento Físico Aeróbico (TFA) de moderada intensidade e de uma intervenção controle, na positividade do Teste de Inclinação Passiva (TIP) e no tempo de tolerância ortostática. Métodos: Foram estudados 21 pacientes com história de síncope neurocardiogênica recorrente e TIP positivo. Esses foram aleatorizados em: Grupo Treinado (GT), n = 11, e Grupo Controle (GC), n = 10. O GT foi submetido a 12 semanas de TFA supervisionado, em cicloergômetro, e o GC, a um procedimento controle que consistia na realização de 15 minutos de alongamentos e 15 minutos de caminhada leve. Resultados: O GT apresentou efeito positivo ao treinamento físico, com aumento significativo do consumo de oxigênio-pico. Já o GC não apresentou nenhuma mudança estatisticamente significante, antes e após a intervenção. Após o período de intervenção, 72,7% da amostra do GT apresentou resultado negativo ao TIP, não apresentando síncope na reavaliação. Conclusão: O programa de treinamento físico aeróbico supervisionado por 12 semanas foi capaz de reduzir o número de TIP positivos, assim como foi capaz de aumentar o tempo de tolerância na posição ortostática ...
Background: Characterized as a sudden and temporary loss of consciousness and postural tone, with quick and spontaneous recovery, syncope is caused by an acute reduction of systemic arterial pressure and, therefore, of cerebral blood flow. Unsatisfactory results with the use of drugs allowed the nonpharmacological treatment of neurocardiogenic syncope was contemplated as the first therapeutic option. Objectives: To compare, in patients with neurocardiogenic syncope, the impact of a moderate intensity aerobic physical training (AFT) and a control intervention on the positivity of head-up tilting test (HUT) and orthostatic tolerance time. Methods: Were studied 21 patients with a history of recurrent neurocardiogenic syncope and HUT. The patients were randomized into: trained group (TG), n = 11, and control group (CG), n = 10. The TG was submitted to 12 weeks of AFT supervised, in cycle ergometer, and the CG to a control procedure that consisted in 15 minutes of stretching and 15 minutes of light walk. Results: The TG had a positive effect to physical training, with a significant increase in peak oxygen consumption. The CG did not show any statistically significant change before and after the intervention. After the intervention period, 72.7% of the TG sample had negative results to the HUT, not having syncope in the revaluation. Conclusion: The program of supervised aerobic physical training for 12 weeks was able to reduce the number of positive HUT, as it was able to increase tolerance time in orthostatic position during the HUT after the intervention period. .