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We sought to investigate the effect of the α1-adrenergic receptor blockade during handgrip exercise (Grip), isolated metaboreflex activation (Metabo), and cold pressor test (CPT) on coronary circulation in young (YW) and postmenopausal women (PMW). Ten YW and 9 PMW underwent two protocols: (1) 3 min of baseline followed by 3 min of CPT and (2) 3 min of rest, 3 min of Grip followed by 3 min of Metabo. Protocols were carried out under control conditions and α1-adrenergic receptor blockade (oral prazosin 0.03 mg·kg -1 ). Coronary blood velocity (CBV) and vascular conductance (CCI) were lower in PMW. Grip increased CBV only in YW (YW: Δ18.0 ± 21.1% vs. PMW: Δ4.2 ± 10.1%; p < 0.05), and the blockade did not change the CBV response to Grip in YW and PMW. During the Metabo, CBV returned to resting levels in YW and was unchanged from rest in PMW, before (YW:Δ1.7 ± 8.7% vs. PMW: Δ- 1.5 ± 8.6) and under the blockade (YW: Δ4.5 ± 14.8% vs. PMW: Δ9.1 ± 29.5%). CPT did not change CBV in both groups (YW: Δ3.9 ± 8.0 vs. PMW: Δ- 4.1 ± 6.2%), following the α1-blockade, CPT increased CBV only in YW (YW: Δ11.2 ± 12.8% vs. PMW: Δ2.2 ± 7.1%; p < 0.05 for group and condition). CCI decreased during Grip, Metabo, and CPT in YW and PMW, while the blockade prevented that decrease only in YW. The α1-adrenergic receptor plays a role in the control of coronary circulation in young women, evoking stronger vasoconstriction during CPT than Grip and Metabo in YW. PMW have impaired vasomotor control in the coronary circulation, which seems not to be caused by the α1-adrenergic receptor., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Objective: To update the estimated cost of physical inactivity for the Brazilian Unified Health System (SUS)., Methods: The hospitalization costs were accessed via a database of the Ministry of Health - Informatics Department of the Brazilian SUS. Physical inactivity for the year 2017 was accessed via the Sistema de Vigilância de Fatores de Risco e Proteção para Doenças Crônicas por Inquérito Telefônico (Vigitel - Surveillance System for Risk and Protective Factors for Chronic Diseases by Telephone Survey). Seven chronic non-communicable diseases (NCD) were selected via the international classification of disease (ICD-10). The population fraction attributable to physical inactivity was calculated based on relative risk reported in previous studies and the prevalence of physical inactivity., Results: In 2017, the seven NCD considered in the analysis were responsible for 154,017 hospital admissions in adults older than 40 years old, residing in the state capitals and the Federal District, which corresponded to 6.5% of hospitalizations and 10.6% of SUS costs at an estimated US$ 112,524,914.47. Considering the group of individuals with insufficient physical activity in their leisure time, the percentage cost attributed to physical inactivity reached 17.4% of the estimated costs with NCD. At a national level, NCD were responsible for approximately 740 thousand hospitalizations, costing US$ 482 million, from which 17.4%, US$ 83 million were attributed to physical inactivity., Conclusion: This study provides evidence to conclude that physical inactivity exerts an economic impact on the SUS due to NCD hospitalization. Physical inactivity is a modifiable lifestyle and compelling evidence, including that of this article, supports the promotion of a more active community as one of the major targets of public health care policies.

Background: Cardiac resynchronization therapy (CRT) may benefit patients with advanced heart failure (HF). Abnormal eccentricity index by gated SPECT is related to structural and functional alterations of the left ventricle (LV)., Objective: The aim of this study is to evaluate the feasibility of LV lead implantation guided by phase analysis and its relationship to ventricular remodeling., Methods: Eighteen patients with indication for CRT underwent myocardial scintigraphy for implant orientation, and eccentricity and ventricular shape parameters were evaluated. P < 0.05 was adopted as statistical significance., Results: At baseline, most patients were classified as NYHA 3 (n = 12). After CRT, 11 out of 18 patients were reclassified to a lower degree of functional limitation. In addition, patients' quality of life was improved post-CRT. Significant reductions were observed in QRS duration, PR interval, end-diastolic shape index, end-systolic shape index, stroke volume, and myocardial mass post-CRT. The CRT LV lead was positioned concordant, adjacent, and discordant in 11 (61.1%), 5 (27.8%), and 2 (11.1%) patients, respectively. End-systolic and end-diastolic eccentricity demonstrated reverse remodeling post-CRT., Conclusions: LV lead implantation in CRT guided by gated SPECT scintigraphy is feasible. The placement of the electrode concordant or adjacent to the last segment to contract was a determinant of reverse remodeling.

Purpose: We investigate the impact of menopause on cardiovascular adjustments to the cold pressor test (CPT) and the role of the α1-adrenergic receptor., Methods: Ten young women (YW) and nine postmenopausal women (MW) underwent 1 min of CPT in control and α1-blockade conditions (0.03 mg‧kg -1 of oral prazosin)., Results: CPT increased heart rate (HR) (YW: ∆20 ± 3 bpm; MW: ∆13 ± 2 bpm) and stroke volume (SV; YW: ∆15 ± 8 ml; MW: ∆9 ± 6 ml; p = 0.01 for time) and evoked a greater increase in cardiac output (CO) in YW (YW: ∆2.1 ± 0.2 l‧m -1 ; MW: ∆1.3 ± 0.5 l‧m -1 ; p = 0.01). α1-Blockade increased baseline HR and did not change HR, SV, and CO responses to CPT. MW presented an exaggerated systolic blood pressure (BP) response (YW: ∆38 ± 9 mmHg; MW: ∆56 ± 24 mmHg; p = 0.03). The α1-blockade did not change baseline BP while blunting its response. Total vascular resistance (TVR) was similar between groups at baseline and increased during CPT only in MW (YW: ∆2.3 ± 1.4 mmHg‧L -1 ‧min; MW:∆6.8 ± 5.9 mmHg‧L -1 ‧min). Under α1-blockade, the TVR increase during CPT was attenuated in MW and abolished in YW (YW: ∆0.3 ± 1.2 mmHg‧L -1 ‧min and MW: ∆3.0 ± 2.0 mmHg‧L -1 ‧min). CPT did not change femoral vascular conductance (FVC) in either group before the blockade (YW: ∆-0.3 ± 4.0 ml‧min -1 ‧mmHg -1 ; MW: ∆-0.2 ± 0.8 ml‧min -1 ‧mmHg -1 ); however, FVC tended to increase in young women (YW: ∆1.3 ± 1.0 ml‧min -1 ‧mmHg -1 ; MW: ∆0.1 ± 1.5 ml‧min -1 ‧mmHg -1 ; p = 0.06) after the α1-blockade., Conclusion: In postmenopausal women, the cardiac ability to adjust to CPT is blunted and α1-adrenergic receptor stimulation is important for the increase in stroke volume. In addition, the peripheral effect of α1-adrenergic receptor stimulation seems to be increased in postmenopausal women., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany.)

Abstract: Filho, MM, Venturini, GRdO, Moreira, OC, Leitão, L, Mira, PA, Castro, JB, Aidar, FJ, Novaes, JdS, Vianna, JM, and Caputo Ferreira, ME. Effects of different types of resistance training and detraining on functional capacity, muscle strength, and power in older women: A randomized controlled study. J Strength Cond Res 36(4): 984-990, 2022-Resistance training (RT) increases muscle strength, power, and functional capacity (FC) of older women. However, these benefits can be lost partially or totally with detraining. This study aimed to compare the effect of 20 weeks of different types of RT and 4 weeks of detraining on muscle strength, power, and FC in older women. Ninety-five older women were randomly divided into 4 experimental groups (strength endurance, power, absolute strength, and relative strength training) and 1 control group (CG). We assessed muscle strength (10RM test) and muscle power of the lower (countermovement jump) and upper limbs (medicine ball pitch). Functional capacity was assessed by the Senior Fitness Test, which comprises the following tests: 30-second arm curl, 30-second chair stand, back scratch, chair sit and reach, 8-foot up and go, and 6-minute walk. The experiment lasted 24 weeks (familiarization: 2 weeks; neural adaptation: 6 weeks; specific training: 12 weeks; and detraining: 4 weeks). Muscle strength, lower and upper limb power (all p < 0.05), 30-second arm curl, 30-second chair stand, 8-foot up and go, 6-minute walk (all p < 0.001), and lower limb flexibility (p = 0.002) improved in all experimental groups after training and CG showed no differences in any of these variables. After detraining, muscle strength, lower and upper limb power (p < 0.05 for all), and FC decreased in comparison to the end of RT (30-second arm curl, 30-second chair stand, 8-foot up and go, 6-minute walk, and lower limb flexibility, p < 0.05 for all). Although the FC of the subjects has been reduced after 4 weeks of detraining, it was maintained at higher levels in comparison to baseline. These results suggested that older women can be submitted to different types of RT to achieve improvements in general fitness., (Copyright © 2022 National Strength and Conditioning Association.)

New Findings: What is the central question of this study? What is the role of β- and α-adrenergic receptors in the control of the coronary circulation during handgrip exercise and isolated muscle metaboreflex activation in humans? What is the main finding and its importance? β-Adrenergic receptor, but not α-adrenergic receptor, blockade significantly blunted the increases in coronary blood velocity observed during handgrip. Coronary blood velocity was unchanged from baseline during isolated muscle metaboreflex activation. This highlights the important role of β-adrenergic receptors in the coronary circulation during handgrip in humans, and the more limited involvement of the α-adrenergic receptors., Abstract: We sought to investigate the role of β- and α-adrenergic receptors in coronary circulation during static handgrip exercise and isolated muscle metaboreflex activation in humans. Seventeen healthy young men underwent two experimental sessions, consisting of 3 min of static handgrip exercise at a target force of 40% maximum voluntary force (not achieved for the full 3 min), and 3 min of metaboreflex activation (post-exercise ischaemia) in two conditions: (1) control and β-blockade (oral propranolol), and (2) control and α-blockade (oral prazosin). In both sessions, coronary blood velocity (CBV, echocardiography) was increased during handgrip (Δ8.0 ± 7.4 cm s -1 ) but unchanged with metaboreflex activation (Δ2.5 ± 3.2 cm s -1 ) under control conditions. β-Blockade abolished the increase in CBV during handgrip, while CBV was unchanged from control with α-blockade. Cardiac work, estimated from rate pressure product (RPP; systolic blood pressure multiplied by heart rate), increased during handgrip and metaboreflex in control conditions in both sessions. β-Blockade reduced RPP responses to handgrip and metaboreflex, whereas α-blockade increased RPP, but the responses to handgrip and metaboreflex were unchanged. CBV and RPP were only significantly correlated during handgrip under control (r = 0.71, P < 0.01) and β-blockade (r = 0.54, P = 0.03) conditions, and the slope of this relationship was unaltered with β-blockade. Collectively, these findings indicate that β-adrenergic receptors play the primary role to the increase of coronary circulation during handgrip exercise, but CBV is unchanged with metaboreflex activation, while α-adrenergic receptor stimulation seems to exert no effect in the control of the coronary circulation during handgrip exercise and isolated muscle metaboreflex activation in humans., (© 2021 The Authors. Experimental Physiology © 2021 The Physiological Society.)

Abnormalities in the muscle metaboreflex concur to exercise intolerance and greater cardiovascular risk. Exercise training benefits neurocardiovascular function at rest and during exercise, but its role in favoring muscle metaboreflex in health and disease remains controversial. While some authors demonstrated that exercise training enhanced the sensitization of muscle metabolically afferents and improved neurocardiovascular responses to muscle metaboreflex activation, others reported unaltered responses. This narrative review aimed to: (a) highlight the current evidence on the effects of exercise training upon cardiovascular and autonomic responses to muscle metaboreflex activation; (b) analyze the role of training components and indicate potential mechanisms of metaboreflex adaptations; and (c) address key methodological features for future research. Though limited, accumulated evidence suggests that muscle metaboreflex adaptations depend on the individual clinical status, exercise modality, and training duration. In healthy populations, most trials negated the hypothesis of metaboreflex improvement due to chronic exercise, irrespective of the training duration. Favorable changes in patients with impaired metaboreflex, particularly chronic heart failure, mostly resulted from long-term interventions (> 16 weeks) including aerobic exercise of moderate to high intensity, performed in isolation or within multimodal training. Potential mechanisms of metaboreflex improvements include enhanced sensitivity of channels and receptors, greater antioxidant capacity, lower metabolite accumulation, increased functional sympatholysis, and muscle perfusion. Future research should investigate: (1) the dose-response relationship of training components within different exercise modalities to elicit improvements in individuals showing intact or impaired muscle metaboreflex; and (2) potential and specific underlying mechanisms of metaboreflex improvements in individuals with different medical conditions., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Purpose: Chemotherapy treatment can lead to cardiovascular toxicity and physical impairment prior to autologous hematopoietic stem cell transplantation (auto-HSCT). Cardiovascular adjustments during exercise and the exercise capacity remain unknown in patients prior to auto-HSCT. Thus, the hemodynamic responses during exercise and exercise capacity were evaluated using a novel effort test in patients prior to auto-HSCT., Methods: Thirty patients prior to auto-HSCT (BMT group: 44.6 ± 14.1 years) and 23 control participants (CON group: 43.9 ± 16.6 years) performed the 6-Minute Step Test (6MST) to assess their exercise capacity and the hemodynamic responses during exercise. Systolic and diastolic blood pressure (SBP and DBP), heart rate (HR), and oxygen saturation (SpO 2 ) were measured during the test. Rate-pressure product (RPP) was calculated multiplying SBP by HR. The highest HR value recorded during the test was compared with the maximum HR predicted by age and was used as % of maximum HR (%HRmax)., Results: The number of steps up and down performed by the BMT group was lower than CON (108.8 ± 25.3 vs. 127.5 ± 34.4 steps, P = 0.02). The BMT group showed a higher magnitude of increase in SBP and RPP during the 6MST when compared to CON (ΔSBP: 18.5 ± 11.45 vs. 8.30 ± 18.46 mmHg, P = 0.01; and ΔRPP: 8197.3 ± 3829.1 vs. 6170.9 ± 3568.9 mmHg beats min -1 , P = 0.05). The BMT group exhibited higher SpO2 and HR values throughout the protocol (P < 0.05), reaching a higher %HRmax than CON group (76.9 ± 9.6 vs. 66.4 ± 8.9%, P < 0.01)., Conclusions: Patients with indication for auto-HSCT have exacerbated chronotropic and pressor responses during exercise and reduced exercise capacity in the 6MST.

Background: Liver cirrhosis (LC) causes several musculoskeletal changes., Objective: To test the hypothesis that the peripheral and inspiratory muscle endurance are reduced in patients with liver cirrhosis., Methods: Twenty-one patients with LC (LC group; 61±14 years) and 18 age-matched subjects (control group; 56±17 years) had accepted to participate in this cross-sectional observational study. To assess peripheral muscle endurance, all volunteers performed a rhythmic handgrip exercise at 45% of their maximum voluntary contraction. A metronome was used to control the contraction-relaxation cycles at 60/min. The inspiratory muscle endurance was assessed using PowerBreath®. Participants underwent inspiratory muscle exercise at 60% of their maximal inspiratory muscle strength. The time until failure characterized the muscle endurance for both handgrip and inspiratory muscle exercises. Additionally, the quality of life of the participants was assessed., Results: The muscle endurance was lower in the LC group when compared to the control group for both handgrip (67 vs 130 s, P<0.001) and inspiratory muscle exercises (40 vs 114 s, P<0.001). The peripheral muscle endurance was directly correlated with the total quality of life score (r=0.439, P=0.01) and to the following domains: fatigue (r=0.378 e P=0.030), activity (r=0.583, P=0.001), systemic symptoms (r=0.316, P=0.073) and preoccupation (r=0.370, P=0.034). The inspiratory muscle endurance was inversely correlated with the total quality of life score (r=0.573, P=0.001) and the following domains: fatigue (r=0.503, P=0.002), activity (r=0.464, P=0.004), systemic symptoms (r=0.472, P=0.004), abdominal symptoms (r=0.461, P=0.005), emotional function (r=0.387, P=0.02) and preoccupation (r=0.519, P=0.001)., Conclusion: Both peripheral and inspiratory muscle endurance were lower in LC patients when compared to the control group.

Background and Aims: The 6-minute walk test (6MWT) is a measure of the overall functional capacity and is associated with the risk of mortality in patients with liver cirrhosis and in those listed for liver transplantation. Nevertheless, physical performance has not yet been established as a predictor of the risk of clinical decompensation in patients with cirrhosis. We aimed to determine the capacity of the 6MWT to predict the clinical decompensation in patients with cirrhosis after 1 year of follow-up., Methods: This prospective cohort study included patients with compensated cirrhosis of several etiologies. All participants had stable clinical conditions for at least 6 months prior to baseline. At baseline, patients performed the 6MWT and were followed up for 1 year to detect the decompensation outcomes., Results: A total of 55 participants completed the evaluation and follow-up. The mean age was 56.3±10.5 years, and 65% were men. Around 65.4% were classified as Child-Pugh class A. In the receiver operating characteristic analysis, a walking distance ≤ 401.8 m during the 6MWT was set as the threshold for predicting clinical decompensation with 64% sensitivity and 82% specificity. Kaplan-Meier curve analysis revealed that patients who covered a distance of < 401.8 m during the test had a decompensation-free outcome rate of 30% as compared to the rate of 75% of those who walked > 401.8 m (p<0.001)., Conclusions: The 6MWT was a significant predictor of clinical decompensation in patients with cirrhosis. A cutoff of 401.8 m was related to an increased risk of clinical decompensation in cirrhotic patients with a stable clinical condition at baseline. The 6MWT should be added to the clinical assessment of the cirrhotic population.

We sought to test the hypothesis that the cardiovascular responses to isolated muscle metaboreflex activation would be blunted in patients with cirrhosis. Eleven patients with cirrhosis and 15 healthy controls were evaluated. Blood pressure (BP; oscillometric method), contralateral forearm blood flow (FBF; venous occlusion plethysmography), and heart rate (HR; electrocardiogram) were measured during baseline, isometric handgrip at 30% of maximal voluntary contraction followed by postexercise ischemia (PEI). Forearm vascular conductance (FVC) was calculated as follows: (FBF / mean BP) × 100. Changes in HR during handgrip were similar between groups but tended to be different during PEI (controls: Δ 0.5 ± 1.1 bpm vs. cirrhotic patients: Δ 3.6 ± 1.0 bpm, P = 0.057). Mean BP response to handgrip (controls: Δ 20.9 ± 2.7 mm Hg vs. cirrhotic patients: Δ 10.6 ± 1.5 mm Hg, P = 0.006) and PEI was attenuated in cirrhotic patients (controls: Δ 16.1 ± 1.9 mm Hg vs. cirrhotic patients: Δ 7.2 ± 1.4 mm Hg, P = 0.001). In contrast, FBF and FVC increased during handgrip and decreased during PEI similarly between groups. These results indicate that an abnormal muscle metaboreflex activation explained, at least partially, the blunted pressor response to exercise exhibited by cirrhotic patients. Novelty: Patients with cirrhosis present abnormal muscle metaboreflex activation. BP response was blunted but forearm vascular response was preserved. HR response was slightly elevated.

Objective: To analyze the sociodemographic and clinical factors associated with the perceived benefits and barriers to physical activity (PA) in subjects with liver cirrhosis., Methods: This cross-sectional study assessed 102 outpatients with liver cirrhosis regarding the clinical and sociodemographic profile and the perceived benefits and barriers to PA by the Exercise Benefits and Barriers Scale and muscle strength. A Generalized Step-Forward linear regression analysis was used to identify the factors associated., Results: The participants were 59±10 years and 60.8% were men. Around 29.4% had ascites decompensation. Perceived benefits and barriers were associated with the presence of ascites (95%CI -0.079 - 0.03; p=0.06 and 95%CI 0.003 - 0.217; p=0.045, respectively). In the group with ascites, both benefits and barriers were associated with muscle strength. In the group without ascites, benefits were associated with cardiovascular risks and no association was observed with barriers to physical activity., Conclusions: Perceived benefits and barriers to physical activity are associated with intrinsic factors such as the presence of ascites and cardiovascular risk in individuals with liver cirrhosis. The results of this study highlight key elements that must be considered for increasing physical activity in this population.

Objective: To investigate the effects of aerobic exercise on the cardiac baroreflex function and vascular reactivity in patients with cirrhosis., Methods: Thirteen patients with cirrhosis were submitted to exercise and control intervention. At baseline and at 30 and 60 min following intervention, we evaluated cardiac baroreflex sensitivity (cBRS) and the baroreflex effectiveness index (BEI) using sequence technique. Vascular reactivity was assessed inducing reactive hyperemia before and 60 min after intervention., Results: At baseline, there was no difference (P interaction = 0.848) between exercise (from 3.0 ± 0.34 to 14.60 ± 1.06 ml/100ml/min) and control sessions (from 2.38 ± 0.10 to 13.73 ± 1.05 ml/100ml/min) regarding the increase in forearm blood flow during reactive hyperemia. However, this response was higher postexercise (from 3.38 ± 0.31 to 16.58 ± 1.58 ml/100ml/min) than postcontrol intervention (from 2.04 ± 0.23 to 11.98 ± 1.16 ml/100ml/min, P interaction < 0.001). BEI increased at 30- and 60-min postexercise (from 32 ± 7 to 42 ± 7 and 46 ± 7%), but not after control intervention (from 33 ± 6 to 31 ± 5 and 33 ± 7%, P interaction = 0.014). In contrast, cBRS decreased at 30-min postexercise (from 10.3 ± 1.9 to 8.2 ± 1.4 and 10.3 ± 2.1 ms/mmHg) and increased postcontrol intervention (from 7.9 ± 0.9 to 10.5 ± 1.5 and 10.3 ± 1.3 ms/mmHg, P interaction = 0.012)., Conclusion: The results suggest that a single bout of aerobic exercise improved cardiac baroreflex function and increased vascular reactivity in patients with early-stage cirrhosis.

Objective: The aim of the study was to compare the quality of life (QOL) of patients undergoing hematopoietic stem cell transplantation who improved their functional capacity during hospitalization (increased functional capacity group) with that of patients who maintained or decreased functional capacity during hospitalization (decreased functional capacity group)., Design: This observational, longitudinal study included 27 hospitalized patients undergoing hematopoietic stem cell transplantation. Patients were divided into increased functional capacity group (16 patients) and decreased functional capacity group (11 patients). Functional capacity (6-min step test), peripheral muscle strength (sit-to-stand test and handgrip strength), and QOL (European Organization for Research and Treatment of Cancer) were assessed at admission and at hospital discharge., Results: Increased functional capacity patients had increased functional capacity and peripheral muscle strength of the lower and upper limbs at hospital discharge (P < 0.01, <0.01, and 0.02, respectively). The patients in the increased functional capacity group demonstrated an increase in global health and reduced symptoms at discharge (P = 0.02 and 0.03, respectively). No significant differences were observed between groups in the functional domain., Conclusions: Patients undergoing hematopoietic stem cell transplantation, who have improved functional capacity at discharge, also experience an improved QOL, with no such improvement noted among patients who have stable or reduced functional capacity. We recommend that the treatment protocol for hospitalized patients undergoing hematopoietic stem cell transplantation include an exercise program aimed at improving functional capacity.

Offspring of hypertensive parents present autonomic dysfunction at rest and during physiological maneuvers. However, the cardiac autonomic modulation during exercise remains unknown. This study tested whether the cardiac autonomic modulation would be reduced in offspring of hypertensive parents during exercise. Fourteen offspring of hypertensive and 14 offspring of normotensive individuals were evaluated. The groups were matched by age (24.5±1.0 vs. 26.6±1.5 years; p=0.25) and BMI (22.8±0.6 vs. 24.2±1.0 kg/m 2 ; p=0.30). Blood pressure and heart rate were assessed simultaneously during 3 min at baseline followed by 3-min isometric handgrip at 30% of maximal voluntary contraction. Cardiac autonomic modulation was evaluated using heart rate variability. Primary variables were subjected to two-way ANOVA (group vs. time). P value<0.05 was considered statistically significant. Blood pressure and heart rate were similar between groups during exercise protocol. In contrast, offspring of hypertensive subjects showed a reduction of SDNN (Basal=34.8±3.5 vs. 45.2±3.7 ms; Exercise=30.8±3.3 vs. 41.5±3.9 ms; p group=0.01), RMSSD (Basal=37.1±3.7 vs. 52.0±6.0 ms; Exercise=28.6±3.4 vs. 41.9±5.3 ms; p group=0.02) and pNN50 (Basal=15.7±4.0 vs. 29.5±5.5%; Exercise=7.7±2.4 vs. 18.0±4.3%; p group=0.03) during the exercise protocol in comparison with offspring of normotensive parents. We concluded that normotensive offspring of hypertensive parents exhibit impaired cardiac autonomic modulation during exercise., Competing Interests: Conflict of interest: The authors have no conflict of interest to declare, (© Georg Thieme Verlag KG Stuttgart · New York.)

Background:: A family history of hypertension is associated with vascular and autonomic abnormalities, as well as an impaired neurohemodynamic response to exercise., Objective:: To test the hypothesis that normotensive individuals with a family history of hypertension present an impaired peripheral vascular resistance response to exercise., Methods:: The study included 37 normotensive volunteers of both sexes who were sedentary, eutrophic, and nonsmokers, comprising 23 with (FH+; 24 ± 3 years) and 14 without (FH-; 27 ± 5 years) a family history of hypertension. Blood pressure, heart rate (DIXTAL®), forearm blood flow (Hokanson®), and peripheral vascular resistance were simultaneously measured for 3 minutes during rest and, subsequently, for 3 minutes during an isometric exercise at 30% of maximal voluntary contraction (Jamar®)., Results:: At rest, the FH+ and FH- groups present similar mean blood pressure (83 ± 7 versus 83 ± 5 mmHg, p = 0.96), heart rate (69 ± 8 bpm versus 66 ± 7 bpm, p = 0.18), forearm blood flow (3 ± 1 mL/min/100 mL versus 2.7 ± 1 mL/min/100 mL, p = 0.16), and peripheral vascular resistance (30 ± 9 units versus 34±9 units, p = 0.21), respectively. Both groups showed a significant and similar increase in mean blood pressure (∆ = 15 ± 7 mmHg versus 14 ± 7 mmHg, p = 0.86), heart rate (∆ = 12 ± 8 bpm versus 13 ± 7 bpm, p = 0.86), and forearm blood flow (∆ = 0.8 ± 1.2 mL/min/100 mL versus 1.4 ± 1.1 mL/min/100 mL, p = 0.25), respectively, during exercise. However, individuals in the FH+ group showed no reduction in peripheral vascular resistance during exercise, which was observed in the FH- group (∆ = -0.4 ± 8.6 units versus -7.2 ± 6.3 units, p = 0.03)., Conclusion:: Normotensive individuals with a family history of hypertension present an impaired peripheral vascular resistance response to exercise., Fundamento:: O histórico familiar para hipertensão arterial está relacionado a anormalidades vasculares e autonômicas, bem como disfunções no comportamento neuro-hemodinâmico durante o exercício físico., Objetivo:: Testar a hipótese de que indivíduos normotensos com histórico familiar de hipertensão arterial apresentam resposta prejudicada da resistência vascular periférica durante o exercício físico., Métodos:: Foram avaliados 37 normotensos de ambos os sexos, sedentários, eutróficos e não tabagistas, sendo 23 com histórico familiar positivo (HF+, 24 ± 3 anos) e 14 com histórico familiar negativo (HF-, 27 ± 5 anos) para hipertensão arterial. Foram identificados pressão arterial, frequência cardíaca (DIXTAL®), fluxo sanguíneo muscular do antebraço e resistência vascular periférica local (Hokanson®) por 3 minutos durante o repouso e, em seguida, 3 minutos durante exercício isométrico de preensão palmar a 30% da contração voluntária máxima (Jamar®)., Resultados:: Em repouso, os grupos HF+ e HF- apresentaram valores semelhantes de pressão arterial média (83 ± 7 mmHg versus 83 ± 5 mmHg, p = 0,96), frequência cardíaca (69 ± 8 bpm versus 66 ± 7 bpm, p = 0,18), fluxo sanguíneo muscular (3 ± 1 mL/min/199 mL versus 2,7 ± 1 mL/min/100 mL, p = 0,16) e resistência vascular periférica (30 ± 9 unidades versus 34 ± 9 unidades, p = 0,21), respectivamente. Durante o exercício, HF+ e HF- mostraram aumento significativo e semelhante da pressão arterial média (∆ = 15 ± 7 mmHg versus 14 ± 7 mmHg, p = 0,86), frequência cardíaca (∆ = 12 ± 8 bpm versus 13 ± 7 bpm, p = 0,86) e fluxo sanguíneo muscular (∆ = 0,8 ± 1,2 mL/min/100 mL versus 1,4 ± 1,1 mL/min/100 mL, p = 0,25), respectivamente. Entretanto, no grupo HF+ não houve redução significativa da resistência vascular periférica durante o exercício, fato que ocorreu no grupo HF- (∆ = -0,4 ± 8,6 unidades versus -7,2 ± 6,3 unidades, p = 0,03)., Conclusão:: Indivíduos normotensos com histórico familiar de hipertensão arterial apresentam resposta prejudicada da resistência vascular periférica durante o exercício físico.

Purpose: The aim of this study was to determine the gain and latency of arterial baroreflex control of heart rate in patients with resistant hypertension compared to patients with essential hypertension and normotensive subjects., Methods: Eighteen patients with resistant hypertension (56 ± 10 years, mean of four antihypertensive drugs), 17 patients with essential hypertension (56 ± 11 years, mean of two antihypertensive drugs), and 17 untreated normotensive controls (50 ± 15 years) were evaluated by spectral analysis of the spontaneous fluctuations of arterial pressure (beat-to-beat) and heart rate (ECG). This analysis estimated vasomotor and cardiac autonomic modulations, respectively. The transfer function analysis quantified the gain and latency of the response of output signal (RR interval) per unit of spontaneous change of input signal (systolic arterial pressure)., Results: The gain was similarly lower in patients with resistant hypertension and patients with essential hypertension in relation to normotensive subjects (4.67 ± 2.96 vs. 6.60 ± 3.30 vs. 12.56 ± 8.81 ms/mmHg; P < 0.01, respectively). However, the latency of arterial baroreflex control of heart rate was significantly higher only in patients with resistant hypertension when compared to patients with essential hypertension and normotensive subjects (-4.01 ± 3.19 vs. -2.91 ± 2.10 vs. -1.82 ± 1.09 s; P = 0.04, respectively). In addition, the index of vasomotor sympathetic modulation was significantly increased only in patients with resistant hypertension when compared to patients with essential hypertension and normotensive subjects (4.04 ± 2.86 vs. 2.65 ± 1.88 vs. 2.06 ± 1.70 mmHg 2 ; P < 0.01, respectively)., Conclusions: Patients with resistant hypertension have reduced gain and increased latency of arterial baroreflex control of heart rate. These patients also have increased vasomotor sympathetic modulation.