RESUMO
OBJECTIVE: Analyze the acute heart rate and blood pressure responses to two protocols of pelvic floor muscles contractions in premenopausal and postmenopausal women. METHODS: Fifty-four women without pelvic floor muscles disorders were eligible and allocated into two groups: premenopausal and postmenopausal. The groups underwent two protocols and the pelvic floor muscle endurance, heart rate, and blood pressure values were monitored. Both protocols included 10 pelvic floor muscles contractions; one series contained contractions lasting 5 s with 5 s of rest between each contraction and the other series contained contractions lasting 10 s with 10 s of rest. RESULTS: In both groups, there was a significant increase in the heart rate during pelvic floor muscles contractions (premenopausal: 71.0 ± 7.3 and 80.3 ± 7.7; postmenopausal: 65.4 ± 6.6 and 73.6 ± 6.6, at rest and contractions peak, respectively) and in systolic blood pressure immediately after the contractions. The observed values during exercise returned to basal values seconds after the contractions. A positive correlation between heart rate and vaginal squeeze pressure (r = 0.45, p = 0.0007 and r = 0.48, p = 0.0003, 5- and 10-s series, respectively) was observed. CONCLUSION: The proposed protocol of isometric pelvic floor muscles contractions caused an increase in heart rate and blood pressure within the normal range and might not represent a cardiovascular risk for healthy postmenopausal women without urinary incontinence and without cardiovascular dysfunctions.
Assuntos
Pressão Sanguínea , Frequência Cardíaca , Distúrbios do Assoalho Pélvico , Incontinência Urinária , Feminino , Humanos , Contração Muscular , Diafragma da Pelve , Estudos ProspectivosRESUMO
Aging affects baroreflex regulation. The effect of senescence on baroreflex control was assessed from spontaneous fluctuations of heart period (HP) and systolic arterial pressure (SAP) through the HP-SAP gain, while the HP-SAP phase and strength are usually disregarded. This study checks whether the HP-SAP phase and strength, as estimated, respectively, via the phase of the HP-SAP cross spectrum (PhHP-SAP) and squared coherence function (K2HP-SAP), vary with age in healthy individuals and trends are gender-dependent. We evaluated 110 healthy volunteers (55 males) divided into five age subgroups (21-30, 31-40, 41-50, 51-60, and 61-70 yr). Each subgroup was formed by 22 subjects (11 males). HP series was extracted from electrocardiogram and SAP from finger arterial pressure at supine resting (REST) and during active standing (STAND). PhHP-SAP and K2HP-SAP functions were sampled in low-frequency (LF, from 0.04 to 0.15 Hz) and in high-frequency (HF, above 0.15 Hz) bands. Both at REST and during STAND PhHP-SAP(LF) showed a negative correlation with age regardless of gender even though values were more negative in women. This trend was shown to be compatible with a progressive increase of the baroreflex latency with age. At REST K2HP-SAP(LF) decreased with age regardless of gender, but during STAND the high values of K2HP-SAP(LF) were more preserved in men than women. At REST and during STAND the association of PhHP-SAP(HF) and K2HP-SAP(HF) with age was absent. The findings points to a greater instability of baroreflex control with age that seems to affect to a greater extent women than men. NEW & NOTEWORTHY Aging increases cardiac baroreflex latency and decreases the degree of cardiac baroreflex involvement in regulating cardiovascular variables. These trends are gender independent but lead to longer delays and asmaller degree of cardiac baroreflex involvement in women than in men, especially during active standing, with important implications on the tolerance to an orthostatic stressor.
Assuntos
Envelhecimento/fisiologia , Pressão Arterial , Barorreflexo , Coração/fisiologia , Caracteres Sexuais , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Taxa Respiratória , Decúbito Dorsal , Adulto JovemRESUMO
NEW FINDINGS: What is the central question of this study? This is the first study to evaluate and describe the cardiovascular responses during maximal expiratory pressure compared with the Valsalva manoeuvre, and whether those responses are similar. What is the main finding and its importance? This study showed that the duration of the manoeuvres appears to be responsible for the different physiological mechanisms involved in the cardiovascular responses to each manoeuvre and that the intensity of expiratory effort was related to the response in maximal expiratory pressure. These results are important to identify the risks to which subjects are exposed when performing these manoeuvres. The main purpose of this study was to compare the cardiovascular responses between the Valsalva manoeuvre (VM) and maximal expiratory pressure (MEP) and to evaluate the effect of age on these responses. Twenty-eight healthy men were evaluated and divided into two groups, younger (n = 15, 25 ± 5 years) and middle aged (n = 13, 50 ± 5 years), and they performed the VM and MEP measurement. The VM consisted of an expiratory effort (40 mmHg) against a manometer for 15 s, and the MEP was performed according to American Thoracic Society guidelines. The cardiovascular responses were analysed at rest, isotime (3 s), peak, nadir and recovery, and the cardiovascular variations (Δ) were calculated as peak or isotime minus resting values. For the statistical analysis, we used two-way ANOVA (P < 0.05). We observed that MEP and the VM generate similar changes in cardiac output (P > 0.05), but MEP presents higher values for mean arterial pressure (MAPPeak , MAPIsotime , ΔMAP and ΔMAPIsotime ) than those observed in the VM (P < 0.05). The execution time of the manoeuvres (VM â¼15 s and MEP â¼5 s) appears to be largely responsible for the activation of different physiological mechanisms involved in the cardiovascular control for each manoeuvre, and the intensity of expiratory effort is related to the higher response of MAP and peripheral vascular resistance (PVRIsotime and ΔPVRIsotime ) during MEP (P < 0.05). Moreover, it appears that age affects only the heart rate and PVR responses (P < 0.05), which were higher in the young and middle-aged group, respectively. Based on these findings, we can conclude that MEP and the VM do not generate similar cardiovascular responses, except for cardiac output.
Assuntos
Sistema Cardiovascular/fisiopatologia , Expiração/fisiologia , Manobra de Valsalva/fisiologia , Adulto , Pressão Sanguínea/fisiologia , Débito Cardíaco/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pressões Respiratórias Máximas/métodos , Pessoa de Meia-Idade , Respiração , Resistência Vascular/fisiologiaRESUMO
BACKGROUND: Circulatory power (CP) and ventilatory power (VP) are indices that have been used for the clinical evaluation of patients with heart failure; however, no study has evaluated these indices in patients with coronary artery disease (CAD) without heart failure. OBJECTIVE: To characterize both indices in patients with CAD compared with healthy controls. METHODS: Eighty-seven men [CAD group = 42 subjects and healthy control group (CG) = 45 subjects] aged 40-65 years were included. Cardiopulmonary exercise testing was performed on a treadmill and the following parameters were measured: 1) peak oxygen consumption (VO2), 2) peak heart rate (HR), 3) peak blood pressure (BP), 4) peak rate-pressure product (peak systolic HR x peak BP), 5) peak oxygen pulse (peak VO2/peak HR), 6) oxygen uptake efficiency (OUES), 7) carbon dioxide production efficiency (minute ventilation/carbon dioxide production slope), 8) CP (peak VO2 x peak systolic BP) and 9) VP (peak systolic BP/carbon dioxide production efficiency). RESULTS: The CAD group had significantly lower values for peak VO2 (p < 0.001), peak HR (p < 0.001), peak systolic BP (p < 0.001), peak rate-pressure product (p < 0.001), peak oxygen pulse (p = 0.008), OUES (p < 0.001), CP (p < 0.001), and VP (p < 0.001) and significantly higher values for peak diastolic BP (p = 0.004) and carbon dioxide production efficiency (p < 0.001) compared with CG. Stepwise regression analysis showed that CP was influenced by group (R2 = 0.44, p < 0.001) and VP was influenced by both group and number of vessels with stenosis after treatment (interaction effects: R2 = 0.46, p < 0.001). CONCLUSION: The indices CP and VP were lower in men with CAD than healthy controls.
Assuntos
Pressão Sanguínea/fisiologia , Doença da Artéria Coronariana/fisiopatologia , Teste de Esforço , Tolerância ao Exercício/fisiologia , Consumo de Oxigênio/fisiologia , Adulto , Idoso , Dióxido de Carbono/metabolismo , Estudos de Casos e Controles , Estudos Transversais , Exercício Físico/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Testes de Função Respiratória , Estatísticas não Paramétricas , Fatores de TempoRESUMO
Background: Circulatory power (CP) and ventilatory power (VP) are indices that have been used for the clinical evaluation of patients with heart failure; however, no study has evaluated these indices in patients with coronary artery disease (CAD) without heart failure. Objective: To characterize both indices in patients with CAD compared with healthy controls. Methods: Eighty-seven men [CAD group = 42 subjects and healthy control group (CG) = 45 subjects] aged 40–65 years were included. Cardiopulmonary exercise testing was performed on a treadmill and the following parameters were measured: 1) peak oxygen consumption (VO2), 2) peak heart rate (HR), 3) peak blood pressure (BP), 4) peak rate-pressure product (peak systolic HR x peak BP), 5) peak oxygen pulse (peak VO2/peak HR), 6) oxygen uptake efficiency (OUES), 7) carbon dioxide production efficiency (minute ventilation/carbon dioxide production slope), 8) CP (peak VO2 x peak systolic BP) and 9) VP (peak systolic BP/carbon dioxide production efficiency). Results: The CAD group had significantly lower values for peak VO2 (p < 0.001), peak HR (p < 0.001), peak systolic BP (p < 0.001), peak rate-pressure product (p < 0.001), peak oxygen pulse (p = 0.008), OUES (p < 0.001), CP (p < 0.001), and VP (p < 0.001) and significantly higher values for peak diastolic BP (p = 0.004) and carbon dioxide production efficiency (p < 0.001) compared with CG. Stepwise regression analysis showed that CP was influenced by group (R2 = 0.44, p < 0.001) and VP was influenced by both group and number of vessels with stenosis after treatment (interaction effects: R2 = 0.46, p < 0.001). Conclusion: The indices CP and VP were lower in men with CAD than healthy controls. .
Fundamento: Os índices da Potência Circulatória (PC) e Potência Ventilatória (PV) têm sido utilizados para avaliação clínica de pacientes com insuficiência cardíaca, mas nenhum estudo avaliou esses índices em pacientes com Doença Arterial Coronariana (DAC). Objetivo: Caracterizar ambos os índices em pacientes com DAC comparados a indivíduos saudáveis. Métodos: Oitenta e sete homens [grupo DAC = 42 sujeitos e, grupo controle (GC) = 45 sujeitos] com idade entre 45 e 65 anos foram incluídos. Um Teste de Exercício Cardiopulmonar (TECP) foi realizado em esteira e as seguintes variáveis foram obtidas: 1) consumo de oxigênio (VO2) pico; 2) Frequência Cardíaca (FC) pico; 3) Pressão Arterial (PA) pico; 4) duplo produto pico (PA sistólica pico x FC pico); 5) pulso de oxigênio pico (VO2 pico dividido pela FC pico); 6) eficiência ventilatória para o consumo de oxigênio (OUES); 7) eficiência ventilatória para a produção de dióxido de carbono (VE/VCO2 slope); 8) PC (VO2 pico x PA sistólica pico); e 9) PV (PA sistólica pico dividido pelo VE/VCO2 slope). Resultados: O grupo DAC apresentou valores significativamente menores das seguintes variáveis no pico do exercício: VO2 (p < 0,001), FC (p < 0,001), PA sistólica (p < 0,001), duplo produto (p < 0,001), pulso de oxigênio (p = 0,008), OUES (p < 0,001), PC (p < 0,001) e PV (p < 0,001), e valores significativamente maiores de PA diastólica (p = 0,004) e VE/VCO2 slope (p < 0,001) em relação ao GC. Uma análise de regressão pelo método stepwise mostrou que a PC foi influenciada pelo grupo (R2 = 0,44, p < 0,001) e a PV tanto pelo grupo quanto pelo número de vasos com estenose pós tratamento (efeito de interação: R2 = 0,46, p < 0,001). Conclusion: Os índices da PC e PV foram menores em homens com DAC comparados ao GC, podendo dessa forma ser utilizados na caracterização dessa população. .
Assuntos
Animais , Humanos , Óxido de Alumínio/toxicidade , Moléculas de Adesão Celular/metabolismo , Adesão Celular/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Células Cultivadas , Moléculas de Adesão Celular/genética , Relação Dose-Resposta a Droga , Selectina E/genética , Selectina E/metabolismo , Endotélio Vascular/metabolismo , Endotélio Vascular/ultraestrutura , Expressão Gênica/efeitos dos fármacos , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Microscopia Eletrônica de Transmissão/métodos , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Monócitos/ultraestrutura , Tamanho da Partícula , RNA Mensageiro/metabolismo , Suínos , Molécula 1 de Adesão de Célula Vascular/genética , Molécula 1 de Adesão de Célula Vascular/metabolismoRESUMO
OBJECTIVE: To investigate the effects of hormone replacement therapy (HRT) on heart rate variability (HRV) in healthy postmenopausal women. METHODS: Two groups were evaluated: group 1 (G1): 20 women not undergoing HRT (60 ± 5.89 years), group 2 (G2): 20 women undergoing HRT (59 ± 5.70 years). The HRTs involved were either conjugated equine estrogen with or without medroxyprogesterone, synthetic estrogen hormone, estradiol associated with norethisterone acetate or isoflavonoids. Electrocardiogram was recorded in the supine position for 10 min. Spectral analysis included low and high frequencies in absolute (LF and HF) and normalized units (LFnu and HFnu), which are predominantly cardiac sympathetic modulation (CSM) and cardiac vagal modulation (CVM) indicators, respectively. The LF/HF ratio was also calculated. Symbolic analysis involved the following indexes: 0V % (CSM indicator), 1V % (CSM and CVM indicators), 2LV % (predominantly CVM indicator) and 2UV % (CVM indicator). Shannon and conditional entropies were also calculated. RESULTS: Spectral analysis demonstrated that HRT affected HRV. LF, LFnu and LF/HF ratio were higher (showing increased CSM), while HFnu was lower (representing decreased CVM) in G2 than in G1. Correlations between complexity indices and HFnu were significant and positive only in G1. INTERPRETATION: Women undergoing HRT presented higher CSM and lower CVM than those who were not. Moreover, the expected positive relationship between CVM and complexity of HRV was found only in control group, thus indicating that CVM in women under therapy drop below a minimal value necessary to the association to become apparent, suggesting an unfavorable cardiac autonomic modulation in spite of HRT.