Vascular effects of isometric handgrip training in hypertensives.

The isometric handgrip training (IHT) has been emerging as an alternative approach for blood pressure (BP) reduction in hypertensive patients. However, the mechanisms underlying the reductions in BP after IHT are poorly known. Thus, the aim of this study was to analyze the vascular effects of IHT in hypertensive patients. A randomized controlled trial was conducted with 33 hypertensive patients (61 ± 2 y.o.; 67% female) who were randomly assigned to two groups: IHT or control group. The IHT group has completed three weekly sessions of isometric handgrip (4 × 2 â€Šmin sets, alternating the hands at 30% of maximal voluntary contraction). Before and after a period of 12 weeks BP, arterial stiffness, central and peripheral pulse wave velocity (PWV) and endothelial function were measured. The IHT approach has significantly decreased systolic (∆ = -16 ± 2 vs. ∆ = -3 ± 3 mmHg, p < 0.001) and diastolic (∆ = -8 ± 2 vs. ∆ = 0 ± 2 mmHg, p = 0.014) BP. Reductions in central PWV (IHT: 9.1 ± 0.5 vs. 8.0 ± 0.3 m/s; Control: 8.8 ± 0.5 m/s, p < 0.05) and shear rate area after occlusion have significantly reduced by using the IHT (37822 ± 6931 vs. 24829 ± 5337 s-1, p < 0.05). In conclusion, 12 weeks of IHT have reduced the BP and arterial stiffness and improved markers of endothelial function in hypertensive patients.

Prevalence of cardiovascular risk factors and socioeconomic level among public-sector workers in Angola.

BACKGROUND: Cardiovascular diseases are the leading cause of death in the majority of developed and developing countries. African countries are currently facing an increase in both cardiovascular and transmitted diseases. In addition, cardiovascular risk varies among different socioeconomic groups. Thus, we determined the prevalence of modifiable cardiovascular risk factors in apparently healthy public-sector workers and investigated possible relationships with socioeconomic status. METHODS: We employed a cross-sectional study comprising 42.2% (n = 615) of the public-sector workers at Agostinho Neto University, 48% (n = 294) male and 52% (n= 321) female, with ages between 20 and 72 years and from various socioeconomic groups. The study was conducted from February 2009 to December 2010. Personal, anthropometric, biochemical, hemodynamic, socioeconomic, and physical activity data were collected. RESULTS: The prevalence rates of cardiovascular risk factors were as follows: hypertension, 45.2% (men 46.3%, women 44.2%, P > 0.05); hypercholesterolemia, 11.1% (men 10.5%, women 11.5%, P > 0.05); low high-density lipoprotein (HDL) cholesterol, 50.1% (men 36.9%, women 62.3%; P < 0.05); hypertriglyceridemia, 10.6% (men 12.6%, women 8.7%, P > 0.05); smoking, 7.2% (men 10.2%, women 4.4%; P < 0.05); diabetes, 5.7% (men 5.5%, women 5.9%, P > 0.05); overweight, 29.3% (men 27.3%, women 31.2%, P > 0.05); obesity, 19.6% (men 9.2%, women 29.0%; P < 0.05); sedentary lifestyle, 87.2% (men 83.0%, women 91,0%, P < 0.05); and left ventricular hypertrophy, 20% (men 32.0%, women 9.0%; P < 0.05). At least one risk factor was present in 27.7% of the sample; 15.2% had two risk factors, and 31.4% had three or more risk factors. Among the individuals with low socioeconomic status, 41.0% had three or more risk factors. CONCLUSIONS: The results of this study suggest the existence of a high prevalence of multiple risk factors for cardiovascular disease in apparently healthy public-sector workers in Angola. The workers in lower socioeconomic groups had higher incidences of hypertension, smoking, and left ventricular hypertrophy.

Effects of exercise intensity on rating of perceived exertion during a multiple-set resistance exercise session.

The aim of this study was to analyze the effects of intensity on rating of perceived exertion (RPE) during a multiple-set resistance exercise session. Fourteen men (22.9 ± 3.8 years) with previous experience in resistance training (22.9 ± 3.8 years) performed 2 experimental sessions in random order: resistance exercise at 50% of 1 repetition maximum (1RM) (E50%) and resistance exercise at 70% of 1RM (E70%). In both sessions, 5 exercises (bench press, bent-over row, frontal raises, arm curl, and overhead triceps extension) were performed in 3 sets of 12, 9, and 6 repetitions, respectively. Active muscle RPEs were measured after each repetition using the OMNI-Resistance Exercise Scale (OMNI-RES). In the 3 sets of 5 exercises, the RPE was higher at E70% than that at E50%. The differences in RPE between intensities were observed in both the first and the sixth repetitions for each exercise. In the E70% session, the RPE increased between sets in all exercises, whereas it did not change in the E50% session. In conclusion, the RPE was higher at 70% of 1RM than that at 50% of 1RM. Moreover, in a multiple-set prescription, the RPE did not change between sets with 50% of 1RM, whereas the RPE increased between sets with 70% of 1RM. These findings suggest that RPE can be effectively used to prescribe and monitor resistance exercise intensity during an entire multiple-set exercise session in young men with previous experience in resistance training.

The antiapoptotic effect of granulocyte colony-stimulating factor reduces infarct size and prevents heart failure development in rats.

BACKGROUND/AIM: Granulocyte colony-stimulating factor (G-CSF) reduces myocardial injury and improves cardiac function after myocardial infarction (MI). We investigated the early alterations provided by G-CSF and the chronic repercussions in infarcted rats. METHODS: Male Wistar rats (200-250g) received vehicle (MI) or G-CSF (MI-GCSF) (50 µg/kg, sc) at 7, 3 and 1 days before MI surgery. Afterwards MI was produced and infarct size was measured 1 and 15 days after surgery. Expression of anti- and proapoptotic proteins was evaluated immediately before surgery. 24 hours after surgery, apoptotic nuclei were evaluated. Two weeks after MI, left ventricular (LV) function was evaluated, followed by in situ LV diastolic pressure-volume evaluation. RESULTS: Infarct size was decreased by 1 day pre-treatment before occlusion (36±2.8 vs. 44±2.1% in MI; P<0.05) and remained reduced at 15 days after infarction (28±2.2 vs. 36±1.4% in MI; P<0.05). G-CSF pretreatment increased Bcl-2 and Bcl-xL protein expression, but did not alter Bax in LV. Apoptotic nuclei were reduced by treatment (Sham: 0.46±0.42, MI: 15.5±2.43, MI-GCSF: 5.34±3.34%; P<0.05). Fifteen days after MI, cardiac function remained preserved in G-CSF pretreated rats. The LV dilation was reduced in MI-G-CSF group as compared to MI rats, being closely associated with infarct size. CONCLUSION: The early beneficial effects of G-CSF were essentials to preserve cardiac function at a chronic stage of myocardial infarction.

Reference values of tissue Doppler imaging and pulsed Doppler echocardiography for analysis of left ventricular diastolic function in healthy adults.

To determine reference values for tissue Doppler imaging (TDI) and pulsed Doppler echocardiography for left ventricular diastolic function analysis in a healthy Brazilian adult population. Observations were based on a randomly selected healthy population from the city of Vitória, Espírito Santo, Brazil. Healthy volunteers (n = 275, 61.7% women) without prior histories of cardiovascular disease underwent transthoracic echocardiography. We analyzed 175 individuals by TDI and evaluated mitral annulus E'- and A'-waves from the septum (S) and lateral wall (L) to calculate E'/A' ratios. Using pulsed Doppler echocardiography, we further analyzed the mitral E- and A-waves, E/A ratios, isovolumetric relaxation times (IRTs), and deceleration times (DTs) of 275 individuals. Pulsed Doppler mitral inflow mean values for men were as follows: E-wave: 71 ± 16 cm/sec, A-wave: 68 ± 15 cm/sec, IRT: 74.8 ± 9.2 ms, DT: 206 ± 32.3 ms, E/A ratio: 1.1 ± 0.3. Pulsed Doppler mitral inflow mean values for women were as follows: E-wave: 76 ± 17, A-wave: 69 ± 14 cm/sec, IRT: 71.2 ± 10.5 ms, DT: 197 ± 33.3 ms, E/A ratio: 1.1 ± 0.3. IRT and DT values were higher in men than in women (P = 0.04 and P = 0.007, respectively). TDI values in men were as follows: E'S: 11± 3 cm/sec, A'S: 13 ± 2 cm/sec, E'S/A'S: 0.89 ± 0.2, E'L: 14 ± 3 cm/sec, A'L: 14 ± 2 cm/sec, E'L/A'L: 1.1± 0.4. E-wave/ E'S ratio: 6.9 ± 2.2; E-wave / E'L ratio: 4.9 ± 1.7. In this study, we determined pulsed Doppler and TDI derived parameters for left ventricular diastolic function in a large sample of healthy Brazilian adults.

Derivation and external validation of a simple prediction model for the diagnosis of type 2 diabetes mellitus in the Brazilian urban population.

A risk score model was developed based in a population of 1,224 individuals from the general population without known diabetes aging 35 years or more from an urban Brazilian population sample in order to select individuals who should be screened in subsequent testing and improve the efficacy of public health assurance. External validation was performed in a second, independent, population from a different city ascertained through a similar epidemiological protocol. The risk score was developed by multiple logistic regression and model performance and cutoff values were derived from a receiver operating characteristic curve. Model's capacity of predicting fasting blood glucose levels was tested analyzing data from a 5-year follow-up protocol conducted in the general population. Items independently and significantly associated with diabetes were age, BMI and known hypertension. Sensitivity, specificity and proportion of further testing necessary for the best cutoff value were 75.9, 66.9 and 37.2%, respectively. External validation confirmed the model's adequacy (AUC equal to 0.72). Finally, model score was also capable of predicting fasting blood glucose progression in non-diabetic individuals in a 5-year follow-up period. In conclusion, this simple diabetes risk score was able to identify individuals with an increased likelihood of having diabetes and it can be used to stratify subpopulations in which performing of subsequent tests is necessary and probably cost-effective.

Supervised, but Not Home-Based, Isometric Training Improves Brachial and Central Blood Pressure in Medicated Hypertensive Patients: A Randomized Controlled Trial.

Meta-analyses have shown that supervised isometric handgrip training reduces blood pressure in hypertensives. However, the mechanism(s) underlying these effects in medicated hypertensive patients, as well as the effects from home-based exercise training, is uncertain. The purpose of this study was to compare the effects of supervised and home-based isometric handgrip training on cardiovascular parameters in medicated hypertensives. In this randomized controlled trial, 72 hypertensive individuals (38-79 years old, 70% female) were randomly assigned to three groups: home-based, supervised isometric handgrip training or control groups. Home-based and supervised isometric handgrip training was completed thrice weekly (4 × 2 min at 30% of maximal voluntary contraction, with 1-min rest between bouts, alternating the hands). Before and after 12 weeks brachial, central and ambulatory blood pressures (BP), arterial stiffness, heart rate variability, vascular function, oxidative stress and inflammation markers were obtained. No significant (p > 0.05) effect was observed for ambulatory BP, arterial stiffness, heart rate variability, vascular function and oxidative stress and inflammatory markers in all three groups. Brachial BP decreased in the supervised group (Systolic: 132 ± 4 vs. 120 ± 3 mmHg; Diastolic: 71 ± 2 vs. 66 ± 2 mmHg, p < 0.05), whereas no significant differences were observed in the home-based (Systolic: 130 ± 4 vs. 126 ± 3 mmHg; diastolic: 73 ± 3 vs. 71 ± 3 mmHg) and control groups (p > 0.05). Supervised handgrip exercise also reduced central BP systolic (120 ± 5 vs. 109 ± 5 mmHg), diastolic (73 ± 2 vs. 67 ± 2 mmHg); and mean BP (93 ± 3 vs. 84 ± 3 mmHg), whereas no significant effects were found in the home-based (Systolic: 119 ± 4 vs. 115 ± 3 mmHg; Diastolic: 74 ± 3 vs. 71 ± 3 mmHg) and control groups (p > 0.05). In conclusion, supervised, but not home-based, isometric training lowered brachial and central BP in hypertensives.

Cardiovascular risk factors in pre-pubertal schoolchildren in Angola.

METHODS: The incidence of obesity is increasing worldwide, especially in countries with accelerated economic growth. We determined the prevalence of and associations between overweight/obesity and cardiovascular risk factors in pre-pubertal (seven- to 11-year-old) schoolchildren (both genders, n = 198) in Luanda, Angola. Biochemical (fasting blood) and clinical examinations were obtained in a single visit. Data are reported as prevalence (95% confidence intervals) and association (r, Pearson). RESULTS: Prevalence of overweight/obesity was 17.7% (12.4- 23.0%), high blood pressure (BP > 90% percentile) was 14.6% (9.7-19.5%), elevated glucose level was 16.7% (11.5-21.9%) and total cholesterol level > 170 mg/dl (4.4 mmol/l) was 69.2% (62.8-75.6%). Significant associations between body mass index (BMI) and systolic and diastolic BP (r = 0.46 and 0.40, respectively; p < 0.05) were found. No association between BMI and elevated glucose or cholesterol levels was found. CONCLUSION: The prevalence of cardiovascular risk factors was high in pre-pubertal schoolchildren in Angola and fat accumulation was directly associated with blood pressure increase but not with other cardiovascular risk factors.

Comparison between symbolic and spectral analyses of short-term heart rate variability in a subsample of the ELSA-Brasil study.

Linear and nonlinear analyses of heart rate variability (HRV) have been largely used to evaluate the autonomic balance directed to the cardiovascular system. However, comparative studies evaluating the agreement between methods are scarce. Therefore, our aim was to examine the relationship between spectral (SPA; linear) and symbolic analyses (SYA; nonlinear) indexes. A subsample of 683 participants of the Brazilian Longitudinal Study of Adult Health was investigated. Linear and nonlinear analyses were obtained from 10 min ECG recording at rest. Reliability and agreement between methods were evaluated by kappa-statistic and proportion of agreement. According to SYA, the most frequent pattern was P1V (sympathovagal balance, without sympathetic or vagal predominance) comprising 62.7% of the sample, followed by P2V (vagal predominance) with 33.2%, and finally P0V pattern (sympathetic predominance) with 4.1%. Overall proportion of agreement between SYA and SPA was 39.68% (95% CI 0.360-0.433), with expected agreement by chance of 30.8%. Kappa value was 0.128 indicating a slight agreement between methods. Proportion of agreement was 7.93% (95% CI 0.032-0.126) for predominant sympathetic modulation, 10.39% (95% CI 0.075-0.132) for sympathovagal modulation, and 40.29% (95% CI 0.361-0.444) for parasympathetic modulation. Our data provide evidence for important differences between SPA and SYA on HRV analysis. More studies are needed to clarify the causes of disagreement between two methods designed to evaluate the autonomic modulation of heart beats.

Long-term intense resistance training in men is associated with preserved cardiac structure/function, decreased aortic stiffness, and lower central augmentation pressure.

OBJECTIVE: There have been contradictory reports regarding resistance exercise and central arterial compliance. The American Heart Association has recommended its use in preventing/treating cardiovascular diseases. We examined the effects of long-term endurance running and intense resistance training on central hemodynamics, compared with healthy control (CON). METHODS: Sixty-nine male participants, 25-50 years [19 intense resistance trained (IRT) group, 21 endurance runners, and 29 CON] were investigated by radial tonometry-pulse wave analysis, pulse wave velocity (PWV), and echocardiogram. Data were expressed as mean ± SE (median). Differences were tested by analysis of variance and analysis of covariance was used to adjust for confounding variables. RESULTS: There were no differences among groups regarding age, height (Ht), brachial and central blood pressure. Resting heart rate (HR) was lower and high-density lipoprotein cholesterol (HDL-C) higher in endurance runners. Weight, peripheral pulse pressure, and pulse pressure amplification were higher and HDL-C lower in the IRT group. Left ventricular mass and creatine phosphokinase were higher in trained participants. Relative wall thickness was similar among groups. The ratio of the velocity of peak E and A waves (E/A) was higher and PWV significantly lower in endurance runners (7.2 ± 0.14 m/s) and IRT (7.5 ± 0.14 m/s) as compared with CON (8.2 ± 0.16 m/s) even after adjustments for age, Ht, HR and mean arterial pressure (MAP), or mean systolic pressure. Differences in central augmentation pressure (cAP) adjusted for age, height, systolic or MAP, PWV, and HR (IRT equal to 0.08 ± 0.9, CON equal to 3.4 ± 0.9 and endurance running equal to 3.6 ± 1) were no longer significant after further adjustments to aortic diameter or weight. CONCLUSION: Long-term resistance training in men is associated with preserved cardiac structure/function, decreased aortic stiffness, and lower cAP.

Isometric handgrip training does not improve quality of life in hypertensives / Treinamento isométrico com handgrip não melhora qualidade de vida em hipertensos

Hypertensive patients have high blood pressure and poor cardiovascular health and it is known that hypertension negatively affects people's health-related quality of life. Meta-analyses have shown that isometric handgrip training (IHT) reduces blood pressure in hypertensives, but the effects of IHT on health-related quality of life is unknown. Therefore, we tested the hypotheses that the IHT improves health-related quality of life in hypertensives. In this randomized controlled trial, 48 hypertensive individuals were randomly assigned to two groups: IHT and control. IHT was completed thrice weekly (4 × 2 min at 30% of maximal voluntary contraction). Before and after 12 weeks healthrelated quality of life was assessment through Medical Outcomes Study Questionnaire Short Form 36 (SF36). No significant effect was observed for physical function (IHT: 85.6±4.6 vs. 81.1±7.2; Control: 78.6±76.7±4.9), physical problems (IHT: 71.4±10.1vs. 83.9±8.1; Control: 73.8±8.2 vs. 64.3±8.0), general health (IHT: 56.1±3.7 vs. 57.1±1.9; Control: 54.3±1.6 vs. 57.6±2.1), pain (IHT: 23.6±4.6 vs. 30.7±5.8; Control: 32.9±4.5 vs. 31.9±4.3), social aspects (IHT: 46.4±3.6 vs. 50.0±2.3; Control: 48.8±2.7 vs. 48.8±1.7), emotional problems (IHT: 85.7±8.4 vs. 92.9±5.2; Control: 79.4±7.8 vs. 71.4±6.6), mental health (IHT: 61.7±2.8 vs. 58.0±2.5; Control: 54.5±2.4 ± 55.6±1.9), and vitality (IHT: 60.0±4.3 vs. 58.6±4.0; Control: 50.7±2.9 vs. 53.6±3.0) after 12-weeks of supervised IHT (p>0.05 for all). In conclusion, 12-weeks of IHT does not improve health-related quality of life in hypertensives. Therefore, in order to improve quality of life, other exercises should be an indicated for hypertensive patients...(AU)

Pacientes hipertensos têm pressão arterial elevada e saúde cardiovascular prejudicada, e, sabese que a hipertensão também afeta negativamente a qualidade de vida relacionada a saúde. Meta-análises têm demonstrado que o treinamento de exercício isométrico com handgrip (IHT) reduz pressão arterial, mas os efeitos do IHT na qualidade de vida relacionada a saúde são esconhecidos. Portanto, foi testado a hipótese que o IHT melhora a qualidade de vida relacionada a saúde em hipertensos. Nesse ensaio clínico controlado randomizado, 48 hipertensos foram randomizados em IHT e controle. IHT foi realizado três vezes semanais (4 x 2 minutos a 30% da contração voluntária máxima). Antes e após 12 semanas, a qualidade de vida relacionada a saúde foi avaliada pelo Medical Outcomes Study Questionnaire Short Form 36. Nenhum efeito significante foi observado para função física (IHT: 85,6±4,6 vs. 81,1±7,2; Controle: 78,6±76,7±4,9), problemas físicos (IHT: 71,4±10,1 vs. 83,9±8,1; Controle: 73,8±8,2 vs. 64,3±8,0), estado geral de saúde (IHT: 56,1±3,7 vs. 57,1±1,9; Controle: 54,3±1,6 vs. 57,6±2,1), dor (IHT: 23,6±4,6 vs. 30,7±5,8; Controle: 32,9±4,5 vs. 31,9±4,3), aspectos sociais (IHT: 46,4±3,6 vs. 50,0±2,3; Controle: 48,8±2,7 vs. 48,8±1,7), problemas emocionais (IHT: 85,7±8,4 vs. 92,9±5,2; Controle: 79,4±7,8 vs. 71,4±6,6), saúde mental (IHT: 61,7±2,8 vs. 58,0±2,5; Controle: 54,5±2,4 ± 55,6±1,9), e vitalidade (IHT: 60,0±4,3 vs. 58,6±4,0; Controle: 50,7±2,9 vs. 53,6±3,0) após 12 semanas de IHT (p>0.05 para todos). Em conclusão, 12 semanas de IHT não melhora a qualidade de vida relacionada a saúde em hipertensos. Portanto, para melhorar a qualidade de vida, outras modalidades de exercício deveriam ser indicadas para pacientes hipertensos...(AU)

A single bout of resistance exercise does not modify cardiovascular responses during daily activities in patients with peripheral artery disease.

OBJECTIVE: To analyze the posteffects of a single bout of resistance exercise on cardiovascular parameters in patients with peripheral artery disease (PAD). DESIGN: Randomized cross-over. MATERIALS AND METHODS: Seventeen PAD patients performed two experimental sessions: control (C) and resistance exercise (R). Both sessions were identical (eight exercises, 3×10 repetitions), except that the R session was performed with an intensity between 5 and 7 in the OMNI-RES scale and the C session was performed without any load. Systolic blood pressure (BP), diastolic BP, heart rate, and rate-pressure product (RPP) were measured for 1 h after the interventions in the laboratory and during 24-h using ambulatory BP monitoring. RESULTS: After the R session, systolic BP (greatest reduction: -6±2 mmHg, P<0.01) and RPP (greatest reduction: -888±286 mmHg×bpm; P<0.01) decreased until 50 min after exercise. From the second hour until 23 h after exercise, BP, heart rate, and RPP product were similar (P>0.05) between R and C sessions. BP load, nocturnal BP fall, and morning surge were also similar between R and C sessions (P>0.05). CONCLUSION: A single bout of resistance exercise decreased BP and cardiac work for 1 h after exercise under clinical conditions, and did not modify ambulatory cardiovascular variables during 24 h in patients with PAD.

Age- and gender-specific reference values of pulse wave velocity for African adults: preliminary results.

Pulse wave velocity (PWV) is an independent predictor of cardiovascular (CV) risk. Higher PWV values have been observed in Africans; however, there are no established age- and gender-adjusted reference values for this population. Therefore, PWV was measured using a validated device (Complior SP) in 544 subjects recruited from an occupational cohort of employees of a public university in Angola. Since high blood pressure (BP) is an important factor influencing PWV, a subsample of 301 normotensive subjects (aged 22-72 years) was selected for this study. A subset of 131 individuals without CV risk factors was considered the healthy group (HG), while the entire group (n = 301) comprised the less healthy group (LHG). Predictors of PWV were evaluated using multiple regression analyses and age- and gender-specific percentile tables and curves were constructed. Age and PWV means were 36 ± 9.7 years and 6.6 ± 1.0 m/s in the HG, respectively, and 39.9 ± 10.2 years and 7.3 ± 1.3 m/s in the LHG. Age and plasma uric acid (UA) were the only significant PWV predictors in the HG, while age, mean BP (MBP), and gender showed significant prediction of PWV in the multiple regression analysis in the LHG. Age- and gender-adjusted reference values of PWV were provided for healthy and less healthy normotensive Africans. Considering the small sample size of our cohort, these preliminary results should be used cautiously until data on robust sample of the general population can be obtained.

High salt intake does not produce additional impairment in the coronary artery relaxation of spontaneously hypertensive aged rats.

The effect of a salt-based diet on the coronary responsiveness in aged hypertensive rats (SHR) still is unclear. We investigated the effects of high salt intake on the relaxation properties of coronary arteries of aged SHRs. Male SHR (32 week-old) received drinking water (SHR) or 1% NaCl solution (SHR-Salt) for 8 weeks. Isolated coronary segments were subjected to concentration-response curves to acetylcholine (ACh) in the presence or absence of L-NAME (100 µM), enalaprilate (10 µM), losartan (10 µM), and spironolactone (100 µM). Salt intake did not increase blood pressure in old SHRs, but caused ventricular hypertrophy. The endothelium-dependent relaxation in SHRs was lower than in Wistar rats. However, salt intake did not add further impairment. Both enalaprilate and losartan reduced the vasodilator response in coronary arteries from Wistar, but did not affect SHR-salt rats. Conversely, losartan attenuated the impaired ACh relaxation observed in SHR. Spironolactone reduced the relaxation induced by ACh in coronary arteries from Wistar rats but not in SHR. The renin-angiotensin-aldosterone system participates in the impaired coronary relaxation in aged SHR, but does not partake in this deleterious effect under increased salt intake, indicating that age could differentiate the effects of high sodium intake in coronary arteries of SHR.

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.

Low-intensity resistance exercise does not affect cardiac autonomic modulation in patients with peripheral artery disease.

OBJECTIVE: To analyze the effect of a single bout of resistance exercise on cardiac autonomic modulation in patients with peripheral artery disease. METHODS: Fifteen patients with peripheral artery disease (age: 58.3±4.0 years) underwent the following sessions in a random order: resistance exercise (three sets of 10 repetitions of the six resistance exercises with a workload of 5-7 in the OMNI-RES scale) and control (similar to the resistance session; however, the resistance exercises were performed with no load). The frequency domain (low frequency, high frequency and sympathovagal balance) and symbolic analysis (0V, 1V and 2V patterns) of heart rate variability were obtained before and until one hour after the interventions. RESULTS: After the resistance exercise and control sessions, similar increases were observed in the consecutive heartbeat intervals (control: 720.8±28.6 vs. 790.9±34.4 ms; resistance exercise: 712.9±30.1 vs. 756.8±37.9 ms; p<0.05) and in the pattern of the symbolic analysis with no variation (0V) (control: 25.1±3.5 vs. 33.4±4.1%; resistance exercise: 26.1±3.2 vs. 29.7±3.5%; p<0.05) until 50 min after both interventions. The pattern of two variations (2V) decreased similarly (control: 11.2±2.1 vs. 8.3±2.1%; resistance exercise: 9.5±1.7 vs. 7.8±1.7%; p<0.05). In contrast, the pattern of one variation (1V), the low and high frequency bands and sympathovagal balance did not change after the interventions (p>0.05). CONCLUSION: A single bout of resistance exercise did not alter cardiac autonomic modulation in patients with peripheral artery disease.

Body mass index is not independently associated with increased aortic stiffness in a Brazilian population.

BACKGROUND: Obesity has been described as a predictor of cardiovascular mortality, and some studies have reported an association with obesity and increased aortic stiffness. Other studies have not identified obesity to be an independent risk factor. Therefore, the purpose of our study was to determine the association between aortic stiffness and obesity in the Brazilian population. METHODS: A cross-sectional study recruited 1,662 individuals aged 25-64 years from the population of Vitória, Brazil following the guidelines of the MONICA-WHO Project. Anthropometric, clinical, and hemodynamic measurements and analyses of aortic stiffness (using carotid-femoral pulse wave velocity

Long-term use of low-dose spironolactone in spontaneously hypertensive rats: effects on left ventricular hypertrophy and stiffness.

The aim of the present study was to evaluate the effect of low-dose spironolactone initiated during the early stages of hypertension development and to assess the effects of chronic pressure overload on ventricular remodeling in rats. Male spontaneously hypertensive rats (SHRs) (4 weeks) were randomized to receive daily spironolactone (20 mg/kg) or vehicle (mineral oil) from 4 weeks to 8 months of age. Systolic blood pressure was measured non-invasively by tail-cuff pletysmography at baseline, 4 and 8 months. Hemodynamic assessment was performed at the end of treatment by arterial and ventricular catheterization. An in situ left ventricular pressure-volume curve was created to evaluate dilatation and wall stiffness. Systolic blood pressure at 1 month of age was higher in SHRs than in the Wistar group; it increased throughout the follow-up period and remained elevated with treatment (Wistar: 136 ± 2, SHR: 197 ± 6.8, SHR-Spiro: 207 ± 7.1 mmHg; p < 0.05). Spironolactone reduced cardiac hypertrophy (Wistar: 1.25 ± 0.03 SHR: 1.00 ± 0.03, SHR-Spiro: 0.86 ± 0.02 g; p < 0.05) and left ventricular mass normalized to body weight (Wistar: 2.51 ± 0.06, SHR: 2.70 ± 0.08, 2.53 ± 0.07 mg/g; p < 0.05). Moreover, the left ventricular wall stiffness that was higher in SHRs was partially reduced by spironolactone treatment (Wistar: 0.370 ± 0.032; SHR: 0.825 ± 0.058; SHR-Spiro: 0.650 ± 0.023 mmHg/ml; p < 0.05). Our results show that long-term spironolactone treatment initiated at the early stage of hypertension development reduces left ventricular hypertrophy and wall stiffness in SHRs.

Low-intensity resistance exercise does not affect cardiac autonomic modulation in patients with peripheral artery disease

OBJECTIVE: To analyze the effect of a single bout of resistance exercise on cardiac autonomic modulation in patients with peripheral artery disease. METHODS: Fifteen patients with peripheral artery disease (age: 58.3±4.0 years) underwent the following sessions in a random order: resistance exercise (three sets of 10 repetitions of the six resistance exercises with a workload of 5-7 in the OMNI-RES scale) and control (similar to the resistance session; however, the resistance exercises were performed with no load). The frequency domain (low frequency, high frequency and sympathovagal balance) and symbolic analysis (0V, 1V and 2V patterns) of heart rate variability were obtained before and until one hour after the interventions. RESULTS: After the resistance exercise and control sessions, similar increases were observed in the consecutive heartbeat intervals (control: 720.8±28.6 vs. 790.9±34.4 ms; resistance exercise: 712.9±30.1 vs. 756.8±37.9 ms; p<0.05) and in the pattern of the symbolic analysis with no variation (0V) (control: 25.1±3.5 vs. 33.4±4.1%; resistance exercise: 26.1±3.2 vs. 29.7±3.5%; p<0.05) until 50 min after both interventions. The pattern of two variations (2V) decreased similarly (control: 11.2±2.1 vs. 8.3±2.1%; resistance exercise: 9.5±1.7 vs. 7.8±1.7%; p<0.05). In contrast, the pattern of one variation (1V), the low and high frequency bands and sympathovagal balance did not change after the interventions (p>0.05). CONCLUSION: A single bout of resistance exercise did not alter cardiac autonomic modulation in patients with peripheral artery disease. .

Impacto da atividade física sobre o risco cardiovascular na população adulta de Vitória-ES / Impact of physical activity on cardiovascular risk in adults from Vitória-ES

A atividade física (AF) regular é considerada hábito de vida saudável por reduzir o risco de doenças cardiovasculares. Entretanto, há poucos estudos neste sentido realizados em amostras populacionais. Avaliar o impacto da AF de lazer (AFL), ocupacional (AFO) e mista (AFLO) sobre o risco cardiovascular mensurado pelo escore de Framingham (EF) na população adulta (25-64 anos) de Vitória-ES. Estudo transversal em amostra probabilística (N=1.663; ambos os sexos). Os dados foram coletados por meio de questionário, avaliação clínica e laboratorial (coleta de sangue). A estimativa de gasto calórico semanal em AFL, AFO e AFLO foi feita por meio de entrevista e, dessa forma, 4 grupos foram constituídos: Sedentário (S), AFL, AFO e AFLO. Análises de variância e covariância, bem como testes qui-quadrado e Mantel-Haenszel, foram usados para análise estatística. O grupo AFO apresentou valores inferiores para % gordura (%G), colesterol total (CT) e LDL se comparado ao grupo S. A prevalência de tabagismo foi menor nos grupos AFL (11,5%) e AFLO (10,2%), e maior nos grupos S (26,4%) e AFO (30,2%). O EF e o risco (%) de desenvolvimento de doença arterial coronariana em 10 anos (risco DAC), não ajustados, apresentaram-se menores no grupo AFO(EF= 3; 2,65±6,20; risco DAC= 4; 6,79±6,68%; mediana; média±DP ) se comparado ao grupo S (EF= 5;3,85±7,07; risco DAC= 6; 8,41±7,74%). Entretanto, após ajuste para idade e CT, o EF e o risco DAC foram menores no grupo AFL (EF: 2,54±4,18; risco DAC: 6,55±5,29%; média±DP) se comparado aos grupos S (EF: 3,50±4,17; risco DAC: 8,05±5,33%) e AFO (EF: 4,09±4,19; risco DAC: 8,08±5,35%), evidenciando, assim, que as variáveis CT e idade foram as principais determinantes das diferenças iniciais em favor do grupo AFO. O estudo denota impacto positivo da AF de lazer ou laboral na redução do risco cardiovascular populacional.