The effects of exercise training on autonomic and hemodynamic responses to muscle metaboreflex in people living with HIV/AIDS: A randomized clinical trial protocol.

BACKGROUND: People living with HIV (PLHIV) present impaired muscle metaboreflex, which may lead to exercise intolerance and increased cardiovascular risk. The muscle metaboreflex adaptations to exercise training in these patients are unknown. The present study aims to investigate the effects of a supervised multimodal exercise training on hemodynamic and autonomic responses to muscle metaboreflex activation in PLHIV. METHODS AND DESIGN: In this randomized clinical trial protocol, 42 PLHIV aged 30-50 years will be randomly assigned at a ratio of 1:1 into an intervention or a control group. The intervention group will perform exercise training (3x/week during 12 weeks) and the control group will remain physically inactive. A reference group composed of 21 HIV-uninfected individuals will be included. Primary outcomes will be blood pressure and heart rate variability indices assessed during resting, mental stress, and activation of muscle metaboreflex by a digital sphygmomanometer and a heart rate monitor; respectively. Mental stress will be induced by the Stroop Color-Word test and muscle metaboreflex will be activated through a post-exercise circulatory arrest (PECA) protocol, being the latter performed without and with the application of a capsaicin-based analgesic balm in the exercised limb. Secondary outcomes will be heart rate, peripheral vascular resistance, stroke volume, cardiac output, blood lactate, anthropometric markers and handgrip maximal voluntary contraction. The intervention and control groups of PLHIV will be evaluated at baseline and after the intervention, while the HIV-uninfected reference group only at baseline. DISCUSSION: The findings of the present study may help to elucidate the muscle metaboreflex adaptations to exercise training in PLHIV. TRIAL REGISTRATION: This study will be performed at University of Rio de Janeiro State following registration at ClinicalTrials.gov as NCT04512456 on August 13, 2020.

Muscle mass, strength, bone mineral density and vascular function in middle-aged people living with HIV vs. age-matched and older controls.

INTRODUCTION: Combination antiretroviral therapy (cART) substantially extended the life of people living with HIV (PLHIV). However, prolonged HIV infection and cART increase the risk of comorbidities accelerating age-related muscle, bone, and vascular disorders. This cross-sectional study compared muscle mass and strength, bone mineral density (BMD), and vascular function in middle-aged PLHIV treated with cART vs. non-infected age-matched and older controls. METHODS: After careful screening for secondary diseases and medications, body composition, muscular and vascular function were assessed in 12 PLHIV (43.9±8.7 yrs old; HIV-infection for 16.2±8.6 yrs; on cART for 11.6±9.2 yrs), 12 age-matched (CONT, 43.2±8.5 yrs old), and 12 older (OLDER, 74.4±8.3 yrs old) controls through dual x-ray absorptiometry, isokinetic dynamometry, and venous occlusion plethysmography, respectively. RESULTS: PLHIV and CONT showed similar relative muscle mass (65.3±8.0 vs. 66.9±7.3%, respectively; P= 0.88) and strength (160.7±53.9 vs. 152.0±52.9 N.m-1, respectively; P= 0.90), which were greater than OLDER (80.6±18.8 N.m-1; P= 0.001). Total BMD was similar in PLHIV (1.04±0.13 g.cm-2) and OLDER (1.00±0.15 g.cm-2, P= 0.86), and both groups presented lower values than CONT (1.20±0.13 g.cm-2, P< 0.01). No significant difference across groups was detected for macrovascular reactivity (P= 0.32). CONCLUSION: Age-related osteopenia might be accelerated in middle-aged PLHIV on prolonged cART, as their BMD approached values found in older adults. On the other hand, muscle mass, isokinetic strength, and vasodilation capacity were similar in PLHIV and age-matched uninfected controls.

Exercise training improves microvascular function in patients with Chagas heart disease: Data from the PEACH study.

BACKGROUND: Chagas heart disease (CHD) impairs the systemic microvascular function. We investigated the effects of exercise training on cutaneous microvascular function among patients with CHD. METHODS: Patients from the PEACH study were randomly assigned to a supervised exercise training 3 times/week for 6 months (Trained; n = 10) or a control group (Untrained; n = 8). Both groups underwent evaluation of microvascular function before, and at 3- and 6-months of follow-up. Cutaneous vascular conductance (CVC) was assessed in the skin of the forearm using laser speckle contrast imaging coupled with iontophoresis of acetylcholine (ACh), sodium nitroprusside (SNP) and during post-occlusive reactive hyperemia (PORH). RESULTS: At 3-months of follow-up, no difference was detected between groups in CVC responses to ACh (p = 0.50), SNP (p = 0.26) and HRPO (p = 0.65). However, at 6-months of follow-up, trained vs. untrained patients improved CVC induced by SNP-iontophoresis (0.19 ± 0.10 vs. 0.14 ± 0.15 APU.mmHg-1; p = 0.05) and PORH (0.63 ± 0.15 vs. 0.48 ± 0.18 APU.mmHg-1; p = 0.05). CVC response to ACh-iontophoresis was similar between groups (0.19 ± 0.11 vs. 0.22 ± 0.17 APU.mmHg-1; p = 0.38). CONCLUSION: Exercise training performed during 6 months improved the cutaneous microvascular function of CHD patients. Further studies evaluating the mechanism involved in this response are warranted.

Hemodynamic, metabolic and ventilatory responses to exercise in adults with congenital heart disease / Respostas hemodinâmicas, metabólicas e ventilatórias ao exercício em adultos com cardiopatia congênita

Background: Congenital heart disease in adults shares some features with heart failure (HF), including exercise intolerance, ventilatory inefficiency, inflammatory and neurohormonal activation, cardiac arrhythmias and myocardial fibrosis. Over the last years, cardiopulmonary exercise test has gained importance in the diagnostic and prognostic evaluation of congenital heart diseases, as has already occurred in HF. Objective: To describe the behavior of hemodynamic, metabolic and ventilatory parameters in response to exercise in adults with congenital heart disease. Methods: Observational cross-sectional study evaluating 31 adults with congenital acyanotic or cyanotic heart disease, treated clinically, surgically or percutaneously, referred for cardiopulmonary exercise test. A descriptive analysis of the data was performed. Results: Patients aged 35.7 ± 14.2 years were included. Oxygen consumption (VO2) was 44.86 ± 18.01% of predicted at peak exercise and 36.92 ± 12.93% of predicted maximal VO2 at anaerobic threshold. We found an oxygen uptake efficiency slope (OUES) of 1.49 ± 0.89 (61.43 ± 26.63% of predicted), oxygen pulse of 58.90 ± 22.24% and increment in systolic arterial pressure during exercise was 31.42 ± 21.60 mmHg. Conclusion: Adults with congenital heart disease had similar responses to heart failure patients during exercise ­ reduced aerobic capacity, ventilatory inefficiency for oxygen consumption and limited inotropic response to exercise, characterized by reduced oxygen pulse and small increase in systolic arterial pressure

Influence of Physical Exercise on Advanced Glycation End Products Levels in Patients Living With the Human Immunodeficiency Virus.

Introduction: Combined antiretroviral therapy (cART) used to treat acquired immunodeficiency virus (HIV) induces a number of adverse effects, such as insulin resistance and dyslipidemia, which ultimately increases the cardiovascular risk. Advanced glycation end products (AGEs) have been implicated in the etiology of cardiovascular diseases, diabetes and other chronic diseases. It is known that physical exercise improves the lipid profile, insulin resistance and reduces the risk of cardiovascular diseases. However, the impact of physical exercise on AGE levels in HIV-infected patients has not been so far investigated. Therefore, this study compared AGEs levels in people with and without HIV and verified the effect of physical training on serum AGE levels. Methods: Participants were initially assigned into three groups: healthy control (CTL, n = 35), physically inactive HIV-infected (In-HIV, n = 33) and physically active HIV-infected (Ac-HIV, n = 19). The In-HIV group underwent physical training for 3 months, consisting of 60-min sessions of multimodal supervised exercise (aerobic, resistance and flexibility) with moderate intensity (50-80% heart rate reserve), performed 3 times/week. AGEs were measured in serum by fluorescence spectrometry. Results: At baseline, serum AGEs fluorescence level was significantly higher in inactive HIV-patients when compared to controls or active HIV-patients (In-HIV: 0.93 ± 0.08 vs. controls: 0.68 ± 0.13 and Ac-HIV: 0.59 ± 0.04 A.U.; P < 0.001). Triglycerides were also higher in In-HIV than CTL (182.8 ± 102 vs. 132.8 ± 52.3 mg/dL; P < 0.05). Waist circumference was lower in Ac-HIV, compared to In-HIV and controls (83.9 ± 10.4 vs. 92.9 ± 13.5 and 98.3 ± 12.4, respectively; P < 0.05). Body mass, fasting blood glucose, LDL, HDL, and total cholesterol were similar between groups. After training, AGE levels decreased (Baseline: 0.93 ± 0.08 vs. 3 months follow-up: 0.59 ± 0.04 AU; P < 0.001), no further difference being detected vs. CTL or Ac-HIV. Conclusion: HIV-infected patients under cART exhibited elevated AGEs levels compared to healthy individuals and physically active patients. Short-term aerobic training of moderate intensity counteracted this condition.

Is endothelial microvascular function equally impaired among patients with chronic Chagas and ischemic cardiomyopathy?

BACKGROUND: Chronic Chagas cardiomyopathy (CCC) and cardiomyopathies due to other etiologies involve differences in pathophysiological pathways that are still unclear. Systemic microvascular abnormalities are associated with the pathogenesis of ischemic heart disease. However, systemic microvascular endothelial function in CCC remains to be elucidated. Thus, we compared the microvascular endothelial function of patients presenting with CCC to those with ischemic cardiomyopathy disease. METHODS: Microvascular reactivity was assessed in 21 patients with cardiomyopathy secondary to Chagas disease, 21 patients with cardiomyopathy secondary to ischemic disease and 21 healthy controls. Microvascular blood flow was assessed in the skin of the forearm using laser speckle contrast imaging coupled with iontophoresis of acetylcholine (ACh). RESULTS: Peak increase in forearm blood flow with ACh iontophoresis in relation to baseline was greater in healthy controls than in patients with heart disease (controls: 162.7 ±â€¯58.4% vs. ischemic heart disease: 74.1 ±â€¯48.3% and Chagas: 85.1 ±â€¯68.1%; p < 0.0001). Patients with Chagas and ischemic cardiomyopathy presented similar ACh-induced changes from baseline in skin blood flow (p = 0.55). CONCLUSION: Endothelial microvascular function was equally impaired among patients with CCC and ischemic cardiomyopathy.

The Effects of Unsupervised Home-based Exercise Upon Functional Capacity After 6 Months of Discharge From Cardiac Rehabilitation: A Retrospective Observational Study.

BACKGROUND: It remains unclear whether self-regulated exercise is sufficient to maintain the benefits acquired during formal cardiac rehabilitation (CR). This retrospective observational study investigated the effects of a home-based exercise intervention after discharge from CR upon anthropometric and aerobic capacity markers in clinically stable patients. METHODS: Fifty patients with cardiovascular disease were discharged after 6 months of CR and encouraged to maintain aerobic exercise without supervision. Subsequent to 6 months of follow-up, patients were assigned to compliant (n = 34) or noncompliant (n = 16) groups according to their compliance to the home-based program. Maximal aerobic capacity (VO2peak) and anthropometric data were assessed before CR, at discharge, and after 6 months of follow-up. RESULTS: No statistical differences between compliant and noncompliant groups were observed at baseline and at discharge from CR. At the end of the follow-up, statistical differences across groups were not found for body mass or body mass index, but increases in VO2peak (+3.6 vs. -0.6 ml/kg·min, P = 0.004) and oxygen pulse (+1.5 vs. +0.2 ml/bpm, P = .03) were greater in compliant than noncompliant group. CONCLUSIONS: Self-regulated exercising following CR discharge seems to be effective to maintain gains in exercise capacity acquired during supervised center-based programs.