Respiratory sarcopenia screening in dialysis patients: cross-sectional and multicentre study protocol.

BACKGROUND: Respiratory sarcopenia is characterized by the weakness of respiratory muscles associated with sarcopenia due to aging or systemic diseases such as chronic kidney disease (CKD). Patients with CKD undergoing dialysis are particularly susceptible to respiratory muscle weakness caused by factors such as fluid overload and electrolyte imbalance. This weakness not only affects ventilation but also impairs oxygen uptake and delivery to muscle tissue, potentially leading to severe sarcopenia. Thus, the objective of this study is to conduct a respiratory sarcopenia screening in patients with CKD undergoing haemodialysis (HD) and peritoneal dialysis (PD). METHODS: This is an observational, cross-sectional and multicentre study conducted between March 2023 and March 2025. The study was approved by the Research Ethics Committee at two centres. Sarcopenia diagnosis is determined based on low handgrip strength and amount of appendicular skeletal muscle mass, assessed through bioelectrical impedance analysis. Respiratory sarcopenia is diagnosed in patients with sarcopenia who have low inspiratory muscle strength, evaluated through a manovacuometry test. The severity of sarcopenia and respiratory sarcopenia is defined, respectively, by low physical performance (measured using the Short Physical Performance Battery and Timed-Up and Go test) and pulmonary performance (measured through spirometry). Thus, this study will include 81 patients undergoing dialysis (41 on HD and 40 on PD) from three participating centres. DISCUSSION: The literature has been focused on respiratory function in CKD; however, the relationship with sarcopenia remains understudied. We believe that, similar to appendicular skeleton muscles, the axial skeleton muscles are also likely to weaken with the presence of chronic disease, such as CKD.

Analysis of physical function, muscle strength, and pulmonary function in surgical cancer patients: a prospective cohort study.

The aim of this study was to investigate mobility, physical functioning, peripheral muscle strength, inspiratory muscle strength and pulmonary function in surgical cancer patients admitted to an intensive care unit (ICU). We conducted a prospective cohort study with 85 patients. Mobility, physical functioning, peripheral muscle strength, inspiratory muscle strength, and pulmonary function were assessed using the following tests: ICU Mobility Scale (IMS); Chelsea Critical Care Physical Assessment (CPAx); handgrip strength and Medical Research Council Sum-Score (MRC-SS); maximal inspiratory pressure (MIP) and S-Index; and peak inspiratory flow, respectively. The assessments were undertaken at ICU admission and discharge. The data were analyzed using the Shapiro-Wilk and Wilcoxon tests and Spearman's correlation coefficient. Significant differences in inspiratory muscle strength, CPAx, grip strength, MRC-SS, MIP, S-Index, and peak inspiratory flow scores were observed between ICU admission and discharge. Grip strength showed a moderate correlation with MIP at admission and discharge. The findings also show a moderate correlation between S-Index scores and both MIP and peak inspiratory flow scores at admission and a strong correlation at discharge. Patients showed a gradual improvement in mobility, physical functioning, peripheral and inspiratory muscle strength, and inspiratory flow during their stay in the ICU.

Translation, transcultural adaptation, and validation of the Brazilian Portuguese version of the Obstructive Sleep Apnea Knowledge and Attitudes (OSAKA) questionnaire.

PURPOSE: To analyse the psychometric properties of the translated and cross-culturally adapted version of the OSAKA (Obstructive Sleep Apnea Knowledge and Attitudes) questionnaire in the Brazilian Portuguese language. METHODS: The OSAKA instrument was translated by two independent translators, and the back-translated conciliated version was presented and approved by Washington University, which holds the intellectual property for the OSAKA questionnaire. Physicians from different specialties electronically completed the OSAKA instrument and the ASKME (Assessment of Sleep Knowledge in Medical Education) questionnaire, which was used as an auxiliary instrument to analyse the construct validity. RESULTS: The questionnaire was tested with 176 physicians. The items from the knowledge and attitudes domains presented acceptable internal consistency values, with McDonald's omega coefficients (Ω) of 0.70 and 0.73, respectively. The OSAKA questionnaire showed a moderate correlation with the ASKME instrument (r = 0.60, p < 0.001) and excellent retest reliability, with an intraclass correlation coefficient of 0.81. There were differences in knowledge between the medical specialties (p < 0.001). Regarding attitudes, most respondents considered obstructive sleep apnoea and its diagnosis to be important and felt confident in identifying it, but the same majority did not feel confident in treating the disease. CONCLUSION: The OSAKA instrument, as a translated and cross-culturally adapted Brazilian Portuguese version, presented psychometric properties with adequate reliability and validity.

Inspiratory muscle training on quality of life in individuals with spinal cord injury: A systematic review and meta-analysis.

STUDY DESIGN: Systematic review and meta-analysis. OBJECTIVES: The objective was to summarize the effectiveness of Inspiratory Muscle Training (IMT) on the quality of life in individuals with Spinal Cord Injury (SCI). METHODS: An online systematic literature search was conducted in the following databases: PubMed/MEDLINE, PubMed CENTRAL, EMBASE, ISI Web of Science, SciELO, CINAHL/SPORTDiscus, and PsycINFO. Randomized and non-randomized clinical studies investigating the effectiveness of IMT in quality of life were included in the present study. The results used the mean difference and 95% confidence interval for maximal inspiratory pressure (MIP), forced expiratory volume in 1 s (FEV1), maximal expiratory pressure (MEP), and the standardized mean differences for the quality of life and maximum ventilation volume. RESULTS: The search found 232 papers, and after the screening, four studies met the inclusion criteria and were included in the meta-analytical procedures (n = 150 participants). No changes were demonstrated in the quality of life domains (general health, physical function, mental health, vitality, social function, emotional problem, and pain) after IMT. The IMT provided a considerable effect over the MIP but not on FEV1 and MEP. Conversely, it was not able to provide changes in any of the quality of life domains. None of the included studies evaluated the IMT effects on the expiratory muscle maximal expiratory pressure. CONCLUSION: Evidence from studies shows that inspiratory muscle training improves the MIP; however, this effect does not seem to translate to any change in the quality of life or respiratory function outcomes in individuals with SCI.

Failure of Noninvasive Ventilation in Acute Respiratory Failure is Associated with Higher Mortality in Patients with Solid Tumors: A Retrospective Cohort Study.

BACKGROUND: Noninvasive Ventilation (NIV) is a well-established treatment for Acute Respiratory Failure (ARF) in hematological cancer. However, the NIV impact on mortality in patients with solid tumors is unclear. OBJECTIVE: To define the factors associated with NIV failure and mortality and to describe the mortality risk of patients with solid tumors requiring NIV for ARF treatment in the intensive care unit (ICU). METHODS: A retrospective cohort study of patients with solid tumors admitted into an ICU between Jan 2016 and Dec 2017, for cancer treatment, with ARF diagnosis that had used the NIV as first-line treatment. Our primary outcome was ICU and in-hospital mortality. The secondary outcome was NIV failure. A Cox proportional hazards regression was used to identify variables associated with mortality and NIV failure. Kaplan-Meier analyses were performed to demonstrate cumulative survival. RESULTS: A total of 226 patients with solid tumors were included. The ICU and hospital mortality rates were 57.5% and 69.5%, respectively. NIV failed in 52.2% of the patients. The use of vasopressors (HR 2.48 [95% CI: 1.43-4.30] p = 0.001), baseline lactate (HR 1.20 [95% CI: 1.07-1.35] p = 0.003), baseline PaO2/FiO2 ratio (HR1.33 [1.11-1.55] p = 0.002), and NIV success (HR0.17 [95% CI: 0.10-0.27] p = 0.005) was independently associated with hospital mortality. The use of vasopressors (HR 2.58 [95% CI: 1.41-4.73] p = 0.02), NIV duration (HR 0.93 [95% CI: 0.89-0.97] p = 0.003), and baseline lactate (HR 1.13 [95% CI: 1.06-1.20] p = 0.001) was associated with NIV failure. CONCLUSIONS: NIV failure was independently associated with an increase in both ICU and hospital mortality rates. In patients with NIV therapy indication, the duration of this intervention was associated with NIV failure.

Acute and Time-Course Effects of Osteopathic Manipulative Treatment on Vascular and Autonomic Function in Patients With Heart Failure: A Randomized Trial.

OBJECTIVE: The purposed of this study was to valuate the effect of osteopathic manipulative treatment (OMT) on flow-mediated dilation and heart rate variability of patients with heart failure. BACKGROUND: Osteopathic manipulative treatment modulates both the vascular and autonomic nervous system (ANS) in healthy volunteers. However, the acute and time-course effects of the OMT on patients with an overactive ANS remain unclear. METHODS: This randomized controlled trial study included 20 patients with heart failure aged 50 to 60 years, allocated to a single session of OMT (base of the skull, retromaxillary region, heart, and thoracic duct) or sham. Flow-mediated dilation (FMD) at the brachial artery, hemodynamic measures, and heart rate variability were assessed in 3 periods (baseline, immediately after the intervention, and after 15 minutes). Multivariate analysis of variance procedure was used to compare intervention and periods. RESULTS: The OMT group had a greater FMD modulation compared with the sham (FMD,% =  9.5 vs. -5.6, 95% confidence interval (CI): [6.6, -12.35] vs. [-14.25, 2.8]; p = 0.001) and grater peak diameter (PD, mm =  0.77 vs -0.16 mm, 95% CI: [0.31,-1.24] vs [-0.63, 0.29]; P =  0.001), suggesting an important acute and time-course vascular effect from OMT. We also found some relevant heart rate variability modulation after 15 minutes from OMT: high frequency (HF, ms2 = 295 vs -354, 95% CI: [144.2, -769]; P = .001) and low frequency (LF, ms2) = 670 vs 775, 95% CI: [-98, 3591]; P = .001), suggesting a time-course ANS modulation after OMT. CONCLUSIONS: Osteopathic manipulative treatment was effective at increasing brachial blood flow and stimulating the vagal system in patients with heart failure. Moreover, vascular changes seem to precede the autonomic modulation.

Effect of electrical stimulation on muscle atrophy and spasticity in patients with spinal cord injury - a systematic review with meta-analysis.

STUDY DESIGN: This work is a systematic review with meta-analysis OBJECTIVE: Evaluate the effect of electrical stimulation (ES) on skeletal muscle volume and spasticity in individuals with spinal cord injury (SCI). SETTING: University of Brasilia, Brazil METHODS: Searches were conducted of the Cochrane Library, MEDLINE, CINAHL, PEDro, PsycINFO and EMBASE electronic databases for relevant articles published up to June 2018. No restrictions were imposed regarding the year of publication. The inclusion criteria were randomized controlled trials involving adults with SCI comparing ES to an active or passive control. Two independent reviewers extracted the data from the selected studies and methodological quality was assessed using the PEDro scale. RESULTS: The initial search led to the retrieval of 164 studies, seven of which met the eligibility criteria, but only six were included in the meta-analysis. The six studies comprised 104 patients with complete or incomplete SCI. In the two studies that investigated the use of ES on muscle volume of the lower limbs, the overall effect was statistically significant in patients with acute SCI (mean difference: 0.86; 95% CI: 0.04 to 1.69; p < 0.04). Among the four studies that examined the use of ES for spasticity of the lower limb, the overall effect was non-significant (mean difference: 0.55; 95% CI: -0.31 to 1.41; p = 0.21). CONCLUSIONS: Electrical stimulation was found to be an effective method for increasing muscle volume in SCI patients, but had no effect on spasticity. Further investigation of the effect of ES on spasticity in SCI is needed.

Hemodynamic Effects Induced by Transcutaneous Electrical Nerve Stimulation in Apparently Healthy Individuals: A Systematic Review With Meta-Analysis.

OBJECTIVE: To determine the immediate effects of transcutaneous electrical nerve stimulation (TENS) on heart rate, systolic blood pressure (SBP), and diastolic blood pressure (DBP) in apparently healthy adults (age ≥18y). DATA SOURCES: The Cochrane Library (online version 2014), PubMed (1962-2014), EMBASE (1980-2014), and LILACS (1980-2014) electronic databases were searched. STUDY SELECTION: Randomized controlled trials were included when TENS was administered noninvasively with surface electrodes during rest, and the effect of TENS was compared with that of control or placebo TENS. A sensitive search strategy for identifying randomized controlled trials was used by 2 independent reviewers. The initial search led to the identification of 432 studies, of which 5 articles met the eligibility criteria. DATA EXTRACTION: Two independent reviewers extracted data from the selected studies. Quality was evaluated using the PEDro scale. Mean differences or standardized mean differences in outcomes were calculated. DATA SYNTHESIS: Five eligible articles involved a total of 142 apparently healthy individuals. Four studies used high-frequency TENS and 3 used low-frequency TENS and evaluated the effect on SBP. Three studies using high-frequency TENS and 2 using low-frequency TENS evaluated the effect on DBP. Three studies using high-frequency TENS and 1 study using low-frequency TENS evaluated the effect on heart rate. A statistically significant reduction in SBP (-3.00mmHg; 95% confidence interval [CI], -5.02 to -0.98; P=.004) was found using low-frequency TENS. A statistically significant reduction in DBP (-1.04mmHg; 95% CI, -2.77 to -0.03; I(2)=61%; P=.04) and in heart rate (-2.55beats/min; 95% CI, -4.31 to -0.78; I(2)=86%; P=.005]) was found using both frequencies. The median value on the PEDro scale was 7 (range, 4-8). CONCLUSIONS: TENS seems to promote a discrete reduction in SBP, DBP, and heart rate in apparently healthy individuals.

Aerobic exercise effect on prognostic markers for systolic heart failure patients: a systematic review and meta-analysis.

From previous systematic reviews and meta-analyses, there is consensus about the positive effect of exercise training on exercise capacity for systolic heart failure (HF); however, the effect on actual prognostic markers such as NTproBNP and minute ventilation/carbon dioxide production (VE/VCO2) slope has not been evaluated. The primary aim of the proposed study is to determine the effect of aerobic exercise training (AEX) on the VE/VCO2 slope and NTproBNP. The following databases (up to February 30, 2013) were searched with no language limitations: CENTRAL (The Cochrane Library 2013, issue 2), MEDLINE (from January 1966), EMBASE (from January 1980), and Physiotherapy Evidence Database (PEDro) (from January 1929). We screened reference lists of articles and also conducted an extensive hand search of the literature. Randomized controlled trials of exercise-based interventions with 2-month follow-up or longer compared to usual medical care or placebo were included. The study population comprised adults aged between 18 and 65 years, with evidence of chronic systolic heart failure (LVEF < 45 % and baseline NTproBNP > 300 pg/ml). Two review authors independently extracted data on study design, participants, interventions, and outcomes. We assessed the risk of bias using PEDro scale. We calculated mean differences (MD) or standardized mean differences between intervention and control groups for outcomes with sufficient data; for other outcomes, we described findings from individual studies. Eight studies involving a total of 408 participants met the inclusion criteria across the NTproBNP (5 studies with 191 patients) and VE/VCO2 slope (4 studies with 217 patients). Aerobic exercise significantly improved NTproBNP by a MD of -817.75 [95 % confidence interval (CI) -929.31 to -706.19]. Mean differences across VE/VCO2 slope were -6.55 (95 % CI -7.24 to -5.87). Those patients' characteristics and exercise were similar (frequency = 3-5 times/week; duration = 20-50 min/day; intensity = 60-80 % of VO2 peak) on the included studies. Moreover, the risk of bias across all studies was homogeneous (PEDro scale = 7-8 points). However, based on the statistical analysis, the heterogeneity among the studies was still high, which is related to the variable characteristics of the studies. Aerobic exercise may be effective at improving NTproBNP and the VE/VCO2 slope in systolic HF patients, but these effects are limited to a specific HF population meeting specific inclusion criterion in a limited number of studies. Future randomized controlled studies including diastolic and HF overleap with pulmonary diseases are needed to better understand the exact influence of AEX.

Inspiratory Muscle Training in Phase 1 and 2 Postoperative Cardiac Rehabilitation Following Coronary Artery Bypass Graft Surgery: Systematic Review With Meta-Analysis.

OBJECTIVE: This study aimed to determine the effects of inspiratory muscle training (IMT) on exercise capacity, respiratory muscle strength, length of hospital stay (LOS), and quality of life (QOL) following coronary artery bypass graft surgery. METHODS: The search was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and the Cochrane Handbook and included the databases MEDLINE, EMBASE, CINAHL, Scopus, and CENTRAL. The review included randomized controlled trials utilizing IMT during phase 1 or 2 postoperative cardiac rehabilitation (PoCR) versus alternative treatment (active or passive control) in patients following coronary artery bypass graft surgery. RESULTS: Fifteen studies were included (11 phase 1 studies, 4 phase 2 studies) with no reported adverse events. In phase 1 PoCR, IMT reduced the LOS (-1.02 days; 95% CI = -2.00 to -0.03) and increased exercise capacity (6-minute walk distance) (+75.46 m; 95% CI = 52.34 to 98.57), and maximal inspiratory pressure (MIP) (10.46 cm H2O; 95% CI = 2.83 to 18.10), but had no effect on maximal expiratory pressure. In phase 2 PoCR, IMT increased 6-minute walk distance (45.84 m; 95% CI = 10.89 to 80.80), MIP (-23.19 cm H2O; 95% CI = -31.31 to -15), maximal expiratory pressure (20.18 cm H2O; 95% CI = 9.60 to 30.76), and QOL (-11.17; 95% CI = -17.98 to -4.36), with no effect on peak oxygen uptake. There was a high risk of bias for MIP (75% of the phase 1 studies) and 6MWT (1 of 4 phase 2 studies). The quality of the evidence ranged from very low to moderate. CONCLUSION: IMT significantly improves exercise capacity, respiratory muscle strength, LOS, and QOL in phase 1 and 2 PoCR. IMPACT: IMT may benefit patients during phase 1 and 2 of PoCR, considering the safety, low cost, and potential benefits.

Diaphragm thickness and mobility elicited by two different modalities of inspiratory muscle loading in heart failure participants: A randomized crossover study.

OBJECTIVES: To analyze diaphragmatic thickness, at end-inspiration and end-expiration, diaphragmatic thickening index and mobility via US under two different modalities of inspiratory muscle loading, in two different modalities of inspiratory muscle loading and different load intensities at full-vital capacity maneuvers and the relationship between diaphragmatic thickness with pulmonary function tests in participants with HF. METHODS: This randomized crossover trial, enrolled with 17 HF subjects, evaluated diaphragm thickness (Tdi, mm), fractional thickness (TFdi, %), and mobility (mm) US during low and high intensities (30% and 60% of maximal inspiratory pressure-MIP) with two modalities of inspiratory muscle loading mechanical threshold loading (MTL) and tapered flow-resistive loading (TFRL). RESULTS: Both MTL and TFRL produced a increase in Tdi, but only with high intensity loading compared to baseline-2.21 (0.26) vs. 2.68 (0.33) and 2.73 (0.44) mm; p = .01. TFdi was greater than baseline under all conditions, except during low intensity of TFRL. Diaphragm mobility was greater than baseline under all conditions, and high intensity of TFRL elicited greater mobility compared to all other conditions. Additionally, baseline Tdi was moderately correlated with pulmonary function tests. CONCLUSIONS: MTL and TFRL modalities elicit similar increases in diaphragm thickness at loads, but only during high intensity loading it was greater than baseline. Diaphragm mobility was significantly greater than baseline under both loads and devices, and at high intensity compared to low intensity, although TFRL produced greater mobility compared to modalities of inspiratory muscle loading. There is an association between diaphragm thickness and pulmonary function tests.

Longitudinal strain and myocardial work in symptomatic patients having recovered from COVID-19 and possible associations with the severity of the disease.

COVID-19 may have residual consequences in multiple organs, including the cardiovascular system. The purpose of the present investigation is to quantify myocardial function in symptomatic individuals with long COVID and investigate the association between illness severity and myocardial function. A retrospective cross-sectional study was conducted in which symptomatic individuals with previous COVID-19 underwent echocardiographic analysis of left ventricle global longitudinal strain (LVGLS) and myocardial work (MW). Individuals also performed cardiopulmonary testing (CPX) to assess peak oxygen uptake (VO2peak). Differences between illness severity subgroups were analyzed by the Mann-Whitney test. Correlations were calculated using the Spearman correlation test. Multilinear regressions were performed to evaluate the influences of COVID-19 severity, body mass index, age, and sex on MW. Fifty-six individuals were included (critical subgroup: 17; moderate/severe subgroup: 39), 59% females; median age: 56 years (IQR: 43-63). CPX revealed a substantial reduction in VO2peak (median of 53% of predicted values). LVGLS were not statistically different between subgroups. Global wasted work (GWW) was higher in the critical subgroup [146 (104-212) versus 121 (74-163) mmHg%, p = 0.01], and global work efficiency (GWE) was lower in this subgroup [93 (91-95) versus 94 (93-96), p = 0.03]. Illness severity was the only independent predictor of GWW and GWE (GWW: r2 = 0.167; p = 0.009; GWE: r2 = 0.172; p = 0.005) in multilinear regressions. In our study with long COVID-19 individuals, despite having a similar LVGLS, patients had subclinical LV dysfunction, demonstrated only by an increase in GWW and a decrease in GWE.

Standardization use of the international classification of functioning, disability and health in the determination of health status in patients with post-acute COVID-19 syndrome.

PURPOSE: To propose a standardized method for the use of the International Classification of Functioning, Disability and Health (ICF) to describe the health status in Post-Acute COVID-19 Syndrome (PACS) and investigate interrater agreement in the linking process in instruments and clinical exams using the ICF categories. MATERIALS AND METHODS: Cross-sectional and interrater agreement study that followed the Guidelines for Reporting Reliability and Agreement Studies. Two raters performed the linking coding process in instruments of quality of life, anxiety and depression, fatigue and pulmonary function, inspiratory muscle strength and cardiopulmonary exercise testing. The codes were qualified by standards defined to each instrument and exams. RESULTS: The instrument with the lowest Cohen's Kappa coefficient was anxiety and depression (k = 0.57). Forty ICF codes were linked to clinical instruments and exams. The fatigue instrument presented a higher degree of disability by the qualification process, from severe to complete, in the linked codes. CONCLUSION: The study presents a standardized method for the assessment of the health status of patients with PACS through ICF. Restriction in work performance, socialization and family relationships as well as disabilities in physical endurance, fatigue and exercise tolerance were found in the sample. The agreement between the raters was moderate to perfect, demonstrating that the method can be reproducible.

The body structures and functions, environmental factors, activities and participation in a person's environment are determinant aspects of his health.Ways to measure these aspects are key to assessing health not only as absence of disease, so the International Classification of Disability and Functional Health demonstrates the ability to fully describe health.This study proposes a standardization in the use of the tool to facilitate usability in clinical practice.

Effects of blood flow restriction therapy in patients with knee osteoarthritis: protocol for an overview of systematic reviews.

Background: Osteoarthritis (OA) is the most common and prevalent musculoskeletal disease associated with population aging, negatively impacting function and quality of life. A consequence of knee OA is quadriceps muscle weakness. Musculoskeletal rehabilitation using low load exercises, associated with Blood Flow Restriction (BFR) may be a useful alternative to high load exercises when those cannot be tolerated. Several systematic reviews have reported inconclusive results due to discrepancies in study findings, heterogeneity of results, evaluated time points, and research questions explored. Objective: To perform an overview of systematic reviews with meta-analyses, synthesizing the most recent evidence on the effects of muscle strength training with BFR for knee OA. Methodology: Systematic reviews that include primary controlled and randomized clinical trials will be considered for inclusion. Articles will be considered only if they present a clear and reproducible methodological structure, and when they clearly demonstrate that a critical analysis of the evidence was carried out using instrumented analysis. Narrative reviews, other types of review, overviews of systematic reviews, and diagnostic, prognostic and economic evaluation studies will be excluded. Studies must include adults aged 40 years and older with a diagnosis of knee OA. Two authors will perform an electronic search with guidance from an experienced librarian. The following databases will be searched: PubMed via MEDLINE, Embase, CENTRAL (Cochrane Central Register of Controlled Trials), PEDro, Cumulative Index to Nursing and Allied Health Literature (CINAHL) via EBSCO host, Web of Science, and the gray literature. The search strategy used in the databases will follow the acronym PICOS (population, intervention, comparison, outcome, and study design). Screening (i.e., titles and abstracts) of studies identified by the search strategy will be selected using Rayyan (http://rayyan.qcri.org). The quality assessment will be performed using the "Assessment of Multiple Systematic Reviews" (AMSTAR-2) tool. Systematic Review Registration: PROSPERO, CRD42022367209.

Accurate Prediction Equations for Ventilatory Thresholds in Cardiometabolic Disease When Gas Exchange Analysis is Unavailable: Development and Validation.

AIMS: To develop and validate equations predicting heart rate (HR) at the first and second ventilatory thresholds (VTs) and an optimized range-adjusted prescription for patients with cardiometabolic disease (CMD). To compare their performance against guideline-based exercise intensity domains. METHODS: Cross-sectional study involving 2,868 CMD patients from nine countries. HR predictive equations for first and second VTs (VT1, VT2) were developed using multivariate linear regression with 975 cycle-ergometer cardiopulmonary exercise tests (CPET). 'Adjusted' percentages of peak HR (%HRpeak) and HR reserve (%HRR) were derived from this group. External validation with 1,893 CPET (cycle-ergometer or treadmill) assessed accuracy, agreement, and reliability against guideline-based %HRpeak and %HRR prescriptions using mean absolute percentage error (MAPE), Bland-Altman analyses, intraclass correlation coefficients (ICC). RESULTS: HR predictive equations (R²: 0.77 VT1, 0.88 VT2) and adjusted %HRR (VT1: 42%, VT2: 77%) were developed. External validation demonstrated superiority over widely used guideline-directed intensity domains for %HRpeak and %HRR. The new methods showed consistent performance across both VTs with lower MAPE (VT1: 7.1%, VT2: 5.0%), 'good' ICC for VT1 (0.81, 0.82) and 'excellent' for VT2 (0.93). Guideline-based exercise intensity domains had higher MAPE (VT1: 6.8%-21.3%, VT2: 5.1%-16.7%), 'poor' to 'good' ICC for VT1, and 'poor' to 'excellent' for VT2, indicating inconsistencies related to specific VTs across guidelines. CONCLUSION: Developed and validated HR predictive equations and the optimized %HRR for CMD patients for determining VT1 and VT2 outperformed the guideline-based exercise intensity domains and showed ergometer interchangeability. They offer a superior alternative for prescribing moderate intensity exercise when CPET is unavailable.

Equations to predict heart rate at ventilatory thresholds were developed and externally validated, offering a new perspective when a cardiopulmonary exercise test is unavailable to accurately determine the aerobic exercise intensity domains. Additionally, an adjusted range for exercise intensity prescription based on the percentage of heart rate reserve (%HRR) was provided, utilizing a large sample from eight countries. The proposed equations and the range-adjusted %HRR significantly outperformed the guideline-directed methods for determining exercise intensity, exhibiting higher accuracy, agreement, and reliability. Exercise intensity prescription based on the percentage of heart rate peak showed higher errors, raising concerns about its clinical applicability. Our study may enhance the efficacy of exercise training and physical activity advice when gas exchange analysis is unavailable, potentially leading to improved clinical outcomes, even in low-resource settings. Employing these approaches in research could facilitate more tailored and consistent interventions, introducing a contemporary perspective for studies comparing exercise intensity prescriptions.

Exercise intensity domains determined by heart rate at the ventilatory thresholds in patients with cardiovascular disease: new insights and comparisons to cardiovascular rehabilitation prescription recommendations.

Objectives: To compare the elicited exercise responses at ventilatory thresholds (VTs: VT1 and VT2) identified by cardiopulmonary exercise testing (CPET) in patients with cardiovascular disease (CVD) with the guideline-directed exercise intensity domains; to propose equations to predict heart rate (HR) at VTs; and to compare the accuracy of prescription methods. Methods: A cross-sectional study was performed with 972 maximal treadmill CPET on patients with CVD. First, VTs were identified and compared with guideline-directed exercise intensity domains. Second, multivariate linear regression analyses were performed to generate prediction equations for HR at VTs. Finally, the accuracy of prescription methods was assessed by the mean absolute percentage error (MAPE). Results: Significant dispersions of individual responses were found for VTs, with the same relative intensity of exercise corresponding to different guideline-directed exercise intensity domains. A mathematical error inherent to methods based on percentages of peak effort was identified, which may help to explain the dispersions. Tailored multivariable equations yielded r2 of 0.726 for VT1 and 0.901 for VT2. MAPE for the novel VT1 equation was 6.0%, lower than that for guideline-based prescription methods (9.5 to 23.8%). MAPE for the novel VT2 equation was 4.3%, lower than guideline-based methods (5.8%-19.3%). Conclusion: The guideline-based exercise intensity domains for cardiovascular rehabilitation revealed inconsistencies and heterogeneity, which limits the currently used methods. New multivariable equations for patients with CVD were developed and demonstrated better accuracy, indicating that this methodology may be a valid alternative when CPET is unavailable.

Oxygen Uptake Efficiency Slope in South American Healthy Adults: COMPREHENSIVE REFERENCE VALUES AND INTERNATIONAL COMPARISONS.

PURPOSE: The purpose of this study is to provide comprehensive reference values for oxygen uptake efficiency slope (OUES) in healthy adults. International heterogeneity was also explored through published databases. METHODS: A cross-sectional study was conducted with treadmill cardiopulmonary exercise testing (CPX) from a Brazilian healthy adult sample, in which absolute OUES and values normalized by weight and body surface area (BSA) were calculated. Data were stratified by sex and age group. Prediction equations were calculated using age and anthropometric variables. International data were pooled and differences were explored using factorial analysis of variance or the t test, as appropriate. The OUES age-related patterns were calculated using regression analysis. RESULTS: A total of 3544 CPX were included (1970 males and 1574 females) and the age ranged from 20-80 yr. Males had higher values than females for OUES, OUES/kg, and OUES/BSA. Lower values were found with aging and the data followed a quadratic regression curve. Reference value tables and predictive equations were provided for absolute and normalized OUES in both sexes. International comparisons of absolute OUES values among Brazilian, European, and Japanese data revealed substantial heterogeneity. The OUES/BSA measure minimized the discrepancies between Brazilian and European data. CONCLUSIONS: Our study provided comprehensive OUES reference values in a large healthy adult sample from South America with a wide age range and included absolute and normalized values. Differences observed between Brazilian and European data were reduced in the BSA-normalized OUES.

Impact of COVID-19's on Cardiovascular Rehabilitation Programs in Brazil: An Online Survey-Based Cross-Sectional Study. / Impacto da COVID-19 nos Programas de Reabilitação Cardiovascular no Brasil: Um Estudo Transversal Baseado em uma Pesquisa Online.

BACKGROUND: The COVID-19 pandemic had an impact on cardiovascular rehabilitation (CR) programs in Brazil. OBJECTIVES: To describe the characteristics of CR programs in Brazil, the impacts of the first epidemiological wave of COVID-19 (first 60 days) on the programs and present the initiatives used to overcome the impacts. METHOD: This cross-sectional and retrospective study utilized a specific online survey. Participants were coordinators of CR programs. Variables were presented by Brazilian geographic region and as the following categories: demographic, clinical and operational characteristics. The significance level for statistical analysis was set at 5%. RESULTS: Fifty-nine CR programs were responsible for 5,349 patients, of which only 1,817 were post-acute cardiovascular events, which corresponded to 1.99% of hospitalized patients in the month prior to the survey (n=91,231). The greatest impact was the suspension of on-site activities, which occurred similarly in areas with the highest and the lowest rates of COVID-19 in the period. Forty-five programs (75%) were shortly interrupted, while three (5%) were ended. All 42 programs that already used remote rehabilitation strategies noticed a substantial increase in activities, based primarily on the use of media and video calling. Only three (5%) considered safe to see patients during the first 60 days. CONCLUSIONS: There was a reduction in the number of CR programs with the COVID-19 pandemic. Telerehabilitation activities increased during the first two months of the COVID-19 pandemic, but this was not enough to overcome the reduction in CR program activities across Brazil.

FUNDAMENTO: A pandemia da COVID-19 teve um impacto sobre os programas de reabilitação cardiovasculares (RC) no Brasil. OBJETIVOS: Descrever características dos programas de RC no Brasil, os impactos da primeira onda epidemiológica da COVID-19 (primeiros 60 dias) sobre os programas, e apresentar as iniciativas usadas para superar esses impactos. MÉTODOS: Este estudo transversal e retrospectivo usou um questionário online específico. Os participantes eram coordenadores de programas de RC. As variáveis foram apresentadas por região geográfica do Brasil, como as seguintes categorias: característica demográficas, clínicas e operacionais. O nível de significância estatística foi definido em 5%. RESULTADOS: Cinquenta e nove programas de RC atendiam 5349 pacientes, dos quais somente 1817 eram pacientes após eventos cardiovasculares agudos, o que correspondia a 1,99% dos pacientes internados no mês anterior à pesquisa (n=91.231). O maior impacto foi a suspensão das atividades presenciais, o que ocorreu de maneira similar em áreas com as taxas mais altas e áreas com as taxas mais baixas de COVID-19 no período. Quarenta e quatro (75%) programas foram interrompidos de forma breve, e três (5%) foram encerrados. Todos os 42 programas que já utilizavam estratégias de reabilitação remota notaram aumento substancial nas atividades, baseadas principalmente no uso da mídia e chamadas por vídeo. Somente três (5%) consideraram seguro atender pacientes durante os primeiros 60 dias. CONCLUSÕES: Houve redução no número de programas de RC devido a pandemia da COVID-19. Atividades de telerreabilitação aumentaram durante os primeiros dois meses da pandemia da COVID-19, mas que não foi suficiente para superar a redução nas atividades dos programas de RC no Brasil.

Cardiopulmonary Exercise Testing in Post-COVID-19 Patients: Where Does Exercise Intolerance Come From? / Teste Cardiopulmonar em Pacientes Pós-COVID-19: De Onde vem a Intolerância ao Exercício?

BACKGROUND: Post-COVID-19 exercise intolerance is poorly understood. Cardiopulmonary exercise testing (CPET) can identify the underlying exercise limitations. OBJECTIVES: To evaluate the source and magnitude of exercise intolerance in post-COVID-19 subjects. METHODS: Cohort study assessing subjects with different COVID-19 illness severities and a control group selected by propensity score matching. In a selected sample with CPET prior to viral infection, before and after comparisons were performed. Level of significance was 5% in the entire analysis. RESULTS: One hundred forty-four subjects with COVID-19 were assessed (median age: 43.0 years, 57% male), with different illness severities (60% mild, 21% moderate, 19% severe). CPET was performed 11.5 (7.0, 21.2) weeks after disease onset, with exercise limitations being attributed to the peripheral muscle (92%), and the pulmonary (6%), and cardiovascular (2%) systems. Lower median percent-predicted peak oxygen uptake was observed in the severe subgroup (72.2%) as compared to the controls (91.6%). Oxygen uptake differed among illness severities and controls at peak and ventilatory thresholds. Conversely, ventilatory equivalents, oxygen uptake efficiency slope, and peak oxygen pulse were similar. Subgroup analysis of 42 subjects with prior CPET revealed significant reduction in only peak treadmill speed in the mild subgroup and in oxygen uptake at peak and ventilatory thresholds in the moderate/severe subgroup. By contrast, ventilatory equivalents, oxygen uptake efficiency slope, and peak oxygen pulse did not change significantly. CONCLUSIONS: Peripheral muscle fatigue was the most common exercise limitation etiology in post-COVID-19 patients regardless of the illness severity. Data suggest that treatment should emphasize comprehensive rehabilitation programs, including aerobic and muscle strengthening components.

FUNDAMENTO: A intolerância ao exercício pós-COVID-19 não é bem entendida. O teste de esforço cardiopulmonar (TECP) pode identificar as limitações ao exercício subjacentes. OBJETIVOS: Avaliar a etiologia e a magnitude da intolerância ao exercício em sujeitos pós-COVID-19. MÉTODOS: Estudo de coorte que avaliou sujeitos com níveis de gravidades diferentes da doença COVID-19 e um grupo de controle selecionado por pareamento por escores de propensão. Em uma amostra seleta com TECP anterior à infecção viral disponível, foram realizadas comparações antes e depois. O nível de significância foi de 5% em toda a análise. RESULTADOS: Foram avaliados cento e quarenta e dois sujeitos com COVID-19 (idade mediana: 43 anos, 57% do sexo masculino), com níveis de gravidade de doença diferentes (60% leve, 21% moderada, 19% grave). O TECP foi realizado 11,5 (7,0, 21,2) semanas após o aparecimento da doença, com as limitações ao exercício sendo atribuídas aos sistemas muscular periférico (92%), pulmonar (6%), e cardiovascular (2%). Menor valor mediano do consumo de oxigênio pico percentual foi observado no subgrupo com níveis graves de doença (72,2%) em comparação com os controles (91,6%). O consumo de oxigênio foi diferente entre os grupos com diferentes níveis de gravidade de doença e o controle no pico e nos limiares ventilatórios. Inversamente, os equivalentes ventilatórios, a inclinação da eficiência do consumo de oxigênio, e o pico do pulso de oxigênio foram semelhantes. A análise do subgrupo de 42 sujeitos com TECP prévio revelou uma redução significativa no pico de velocidade da esteira no subgrupo com nível leve de doença, e no consumo de oxigênio no pico e nos limiares ventilatórios nos subgrupos com níveis moderado/grave. Por outro lado, os equivalentes ventilatórios, a inclinação da eficiência do consumo de oxigênio e o pico do pulso de oxigênio não apresentaram alterações significativas. CONCLUSÕES: A fadiga do músculo periférico foi a etiologia de limitação de exercício mais comum em pacientes pós-COVID-19 independentemente da gravidade da doença. Os dados sugerem que o tratamento deve enfatizar programas de reabilitação abrangentes, incluindo componentes aeróbicos e de fortalecimento muscular.

Left ventricular global longitudinal strain and cardiorespiratory fitness in patients with heart failure: systematic review and meta-analysis.

BACKGROUND: There is no definition for strain deformation values in relation to cardiorespiratory fitness (CRF) in different heart failure (HF) phenotypes. AIM: To identify the relationship between echocardiographic systolic function measurements and CRF in HF patients. METHODS: Systematic review and meta-analysis following the PRISMA recommendations. Studies reporting echocardiographic assessments of left ventricular global longitudinal strain (LVGLS), left ventricular ejection fraction (LVEF) and direct measurement of peak oxygen uptake (VO2peak) in HF patients with reduced or preserved LVEF (HFrEF, HFpEF) were included. The patients were divided into Weber classes according to VO2peak. RESULTS: Twenty-five studies involving a total of 2,136 patients (70.5% with HFpEF) were included. Mean LVEF and LVGLS were similar in HFpEF patients in Weber Class A/B and Class C/D. In HFrEF patients, a non-significant difference was found in LVEF between Weber Class A/B (30.2% [95%CI: 29.6 to 30.9%]) and Class C/D (25.2% [95%CI: 20.5 to 29.9%]). In HFrEF patients, mean LVGLS was significantly lower in Class C/D compared to Class A/B (6.5% [95%CI: 6.0 to 7.1%] and 10.3% [95%CI: 9.0 to 11.5%], respectively). The correlation between VO2peak and LVGLS (r2 = 0.245) was nearly twofold stronger than that between VO2peak and LVEF (r2 = 0.137). CONCLUSIONS: Low LVGLS values were associated with low CRF in HFrEF patients. Although a weak correlation was found between systolic function at rest and CRF, the correlation between VO2peak and LVGLS was nearly twofold stronger than that with LVEF, indicating that LVGLS may be a better predictor of CRF in patients with HFrEF.