Acute blood pressure responses after different isometric handgrip protocols in hypertensive patients

OBJECTIVE: The present study analyzed blood pressure responses after a single session of isometric handgrip exercise performed with different volumes and intensities by patients with hypertension. METHODS: This randomized crossover trial submitted 12 hypertensive patients (58±5 years old) to four isometric handgrip exercise sessions in a random order: 4 x 2 min at 30% of the maximal voluntary contraction (S30%); 4 x 2 min at 50% of the maximal voluntary contraction (S50%2min); 4 x 3 min at 30% of the maximal voluntary contraction (S30%3min); and a control session. The systolic and diastolic blood pressure, heart rate, and rate-pressure product were measured pre- and post-exercise (30th min). RESULTS: No significant changes were observed in cardiovascular variables after any session (p>0.05 for all comparisons). Similarly, individual analyses revealed heterogeneity in the responses, including increases in blood pressure observed in some sessions. Patients with reduced blood pressure after an isometric handgrip exercise session exhibited a higher body mass index, diastolic blood pressure and heart rate (p<0.05). They also tended to be younger (p=0.07). CONCLUSION: Isometric handgrip exercise performed with different intensities and volumes did not reduce the blood pressure of hypertensive patients

Association of time spent in physical activities and sedentary behaviors with carotid-femoral pulse wave velocity: A systematic review and meta-analysis

BACKGROUND AND AIMS: Increased arterial stiffness is linked to increased risk of cardiovascular disease and mortality. Studies have reported conflicting results regarding the relationship between arterial stiffness and time spent in sedentary behavior (SB) and physical activity (PA). The objective of this systematic review and meta-analysis was to assess the relationship between objectively measured light PA (LPA), moderate to vigorous PA (MVPA), and SB with the gold standard measurement of arterial stiffness, carotid-femoral pulse wave velocity (cfPWV). METHODS: PubMed, Scopus, and Web of Science were searched for relevant studies published until November 2016. Studies reporting the correlation of objectively measured PA and SB with cfPWV in human adults >18 years old were included in this analysis. Correlation coefficients (CCs) were converted to Z scores via Fisher's z values for the analysis of summary effects, using a random-effects model. RESULTS: Twelve studies were included in the systematic review. The meta-analysis showed a negative correlation between cfPWV and LPA (CC -0.16; 95% CI: -0.29 to -0.03; p=0.02) and MVPA (CC -0.16; 95% CI: -0.26 to -0.06; p<0.01), and a positive relationship between cfPWV and SB (CC 0.23; 95% CI: 0.12 to 0.35; p<0.01). CONCLUSIONS: Time spent in light and moderate physical activities is associated with lower arterial stiffness, while time spent in SB is related to higher arterial stiffness. It suggests that PA at any intensity is favorable for arterial stiffness, whereas SB leads to increased arterial stiffness. Considering that cfPWV has an independent prognostic value, these associations may have important clinical implications

Acute and Chronic Effects of Isometric Handgrip Exercise on Cardiovascular Variables in Hypertensive Patients: A Systematic Review

The aim of this study was to describe, through a systematic review, the acute and chronic effects of isometric handgrip exercise on cardiovascular variables in hypertensive individuals. In this systematic review, we included studies that analyzed whether a single bout or a program with isometric exercises affect cardiovascular variables in hypertensive adults. The electronic database PubMed/Medline was searched for relevant studies published until May 2017. Of the 2927 studies initially identified, 2916 were excluded based on title and abstract and five on the basis of full-text assessment, leaving six studies remaining. In addition, one further study cited in the references of the included articles was included in this review, totaling seven studies included (five studies on the chronic effects of isometric handgrip exercise on cardiovascular parameters). None of the acute studies observed post-exercise hypotension. The majority of the chronic studies found decreases in office blood pressure after isometric handgrip training, with training ranging from 6 to 10 weeks, while heart rate variability parameters were improved in one study and did not change in another. Reduction in oxidative stress was observed; however, this variable was only analyzed in one study. In hypertensives, acute responses to isometric handgrip exercise are very limited due to the small number of studies, therefore more research is required. Furthermore, chronic isometric handgrip training reduces blood pressure; however, there is still a gap in the knowledge on the effects of this modality of exercise on other cardiovascular variables-such as endothelial function, oxidative stress, and cardiac autonomic modulation-which should be addressed in future studies.status: publishe

Association between physical activity and walking capacity with cognitive function in peripheral artery disease patients

OBJECTIVE: To identify the association between objectively measured physical activity and walking capacity with cognitive function in patients with symptomatic peripheral artery disease. METHODS: This was an observational, cross sectional study. One hundred and thirty patients (age 67 ± 8 years) were recruited at a tertiary centre specializing in vascular disease. Cognitive function (global, memory, executive function and attention) was evaluated using the Montreal Cognitive Assessment tool. Physical activity levels (total, light, and moderate-vigorous) were obtained using an accelerometer. A 6 min and 4 m walk test were undertaken to assess walking capacity. Crude and covariate adjusted, linear regression analyses confirmed significant associations between physical activity levels and walking capacity with cognitive function. RESULTS: Positive and significant associations were observed between moderate to vigorous physical activity (p = .039) and walking capacity (p = .030) with memory after adjusting for covariates. No significant association was identified between light physical activity and usual gait speed with any cognitive function outcome. CONCLUSION: Greater memory performance was associated with greater moderate to vigorous physical activity levels and walking capacity in patients with symptomatic peripheral artery disease. Clinical interventions focused on improving moderate to vigorous physical activity levels and walking capacity may provide important therapies to potentially enhance cognitive health in patients with peripheral artery disease

Cintilografia de perfusão miocárdica sob baixa dose de dobutamina na identificação do miocárdio viável Low-dose dobutamine myocardial perfusion scintigraphy in the identification of viable myocardium

OBJETIVO: Verificar se a cintilografia de perfusão miocárdica duoisotópica(99mTc-sestamibi/tálio-201), método de alta sensibilidade para identificação do músculo viável, tem sua especificidade aumentada com a inclusão de informações sobre reserva contrátil miocárdica obtidas simultaneamente através de gated SPECT na vigência de baixas doses de dobutamina de forma semelhante ao ecocardiograma. MATERIAIS E MÉTODOS: Estudaram-se 260 segmentos miocárdicos de 13 pacientes com infarto do miocárdio, encaminhados para pesquisa de viabilidade antes do procedimento de revascularização. Avaliaram-se a integridade celular e a reserva contrátil pela cintilografia de perfusão miocárdica duoisotópica com imagens de repouso e redistribuição do tálio-201 e de estresse (99mTc-sestamibi gated SPECT), em condições basais e na vigência de baixas doses de dobutamina. A melhora do desempenho contrátil em controle cintilográfico pós-revascularização (99mTc-sestamibi gated SPECT) confirmava a presença de viabilidade. Para análise dos resultados quantificaram-se os parâmetros funcionais dos segmentos miocárdicos nas diferentes etapas do estudo, estratificando-os quanto à viabilidade para posterior comparação funcional pós-revascularização. RESULTADOS: No tratamento estatístico a análise do espessamento sistólico se destacou como parâmetro de avaliação da reserva contrátil miocárdica pelo método, mostrando tendência a incremento na especificidade (84%), demonstrando valores superiores aos da literatura. CONCLUSÃO: O método tende a apresentar contribuições efetivas na busca do miocárdio viável.<br>OBJECTIVE: To evaluate the increase in specificity of dual isotope myocardial perfusion gated SPECT (99mTc-sestamibi/thallium-201), a highly sensitive method to detect viable myocardium, with addition of data on contractile reserve simultaneously acquired by low-dose dobutamine gated SPECT, similarly to echocardiography. MATERIALS AND METHODS: A total of 260 myocardial segments were assessed in 13 patients with myocardial infarction referred for investigation of myocardial viability before undergoing revascularization. Cellular integrity and contractile reserve were evaluated by dual isotope perfusion myocardial gated SPECT with thallium rest and redistribution images and post-stress 99mTc-sestamibi gated-SPECT images under basal conditions and with low-dose dobutamine. The improvement in the contractile performance detected by post-revascularization 99mTc-sestamibi gated SPECT was the parameter considered for determining myocardial viability. For the purpose of results analysis, the functional parameters of the myocardial segments were quantified at the different phases of the study and stratified according to their viability for a later post-revascularization functional comparison. RESULTS: In the statistical analysis, systolic wall thickening demonstrated to be a relevant parameter in the evaluation of myocardial contractile reserve by this method, with a tendency of improvement in the specificity (84%), demonstrating higher values than those observed in the literature. CONCLUSION: This method tends to present an effective contribution in the assessment of myocardial viability