Symptom-limited Exercise Test Research Articles

Study on the correlation between type 2 diabetes mellitus combined with non-alcoholic steatohepatitis and aerobic exercise performance

Objective: To study the correlation between patients with type 2 diabetes mellitus combined with nonalcoholic steatohepatitis in order to provide theoretical support for the treatment of NAFLD through aerobic exercise performance. Methods: 253 cases with T2DM combined with NAFLD were selected. 93 cases consented to undergo a liver biopsy. Among them, 74 cases with liver biopsy successfully passed the symptom-limited cardiopulmonary exercise test (CPET) and respiratory quotient (RQ)≥1.05. Patients were divided into two groups according to the NAFLD activity score (NAS) of the pathological biopsy: the non-NASH group (NAS < 4) and the NASH group (NAS≥4). The differences in general clinical and biochemical indicators and exercise parameters were compared between the two groups. The relevant factors that affect aerobic exercise performance in NAFLD patients were explored by correlation and regression analysis. Results: The peak oxygen uptake [VO2 @ peak, (17.82 ± 5.61) ml·kg(-1)·min(-1) and (23.14 ± 5.86) ml·kg(-1)·min(-1)] and anaerobic threshold [VO2 @ AT, (11.47 ± 3.12) ml·kg(-1)·min(-1) and (13.81 ± 3.53) ml·kg(-1)·min(-1)] were lower in the NASH group than those in the non-NASH group in T2DM patients, with P < 0.01, indicating a significant decrease in aerobic exercise performance in NASH patients compared to non-NASH patients. Correlation analysis showed that patients with T2DM combined with NAFLD VO2@peak was positively correlated with RQ, carbohydrate oxidation rate (%CHO), daily carbohydrate energy supply (CHO Kcal/d), high-density lipoprotein cholesterol (HDL-C), and maximal voluntary ventilation (MVV) (r 0.360, 0.334, 0.341, 0.255, 0.294, P < 0.05 or P < 0.01, respectively) and negatively correlated with NAS score, fat attenuation, liver stiffness, fat oxidation rate (%FAT), daily fat energy supply (FAT Kcal/d), aspartate aminotransferase (AST), alanine aminotransferase (ALT), body mass, and body mass index (BMI) (r -0.558, -0.411, -0.437, -0.340, -0.270, -0.288, -0.331, -0.295, -0.469, P < 0.05 or P < 0.01, respectively). VO2@AT were positively correlated with RQ, %CHO, total cholesterol (TC), and HDL-C (r 0.351, 0.247, 0.303, 0.380, P < 0.05 or P < 0.01, respectively), while it was negatively correlated with NAS score, fat attenuation, liver stiffness, %FAT, FAT (Kcal/d), ferritin (Fer), ALT, AST, body weight, and BMI (r -0.330, -0.384, -0.428, -0.270, -0.318, 0.320, -0.404, -0.416, -0.389, -0.520, P < 0.05 or P < 0.01, respectively). Stepwise multiple regression analyses revealed that BMI, RQ, and NAS scores were independent correlated factors of aerobic exercise performance. Conclusion: Hepatic inflammation and fibrosis affect the aerobic exercise performance of patients with T2DM combined with NAFLD.

Sympathovagal Balance and Body Shape Index in Elite and Amateur Athletes: The Relationship Unraveled.

Background Heart rate variability (HRV) is one piece among a complex network of adaptations existent in athletes that help them gain a better understanding of their own physiology. Sympathovagal balance is one of the spectral components of HRV analysis and is used to assess the frequently changing oscillations of a healthy heart, which can help in gauging the response of cardiac function towards physiological stress during exercise. This index is extensively used in appraising cardiac autonomic modulation. An evaluation of body composition in athletes has become a critical consideration when tracking HRV, as it helps practitioners understand the role of the autonomic nervous system (ANS) in obesity. The body shape index (BSI), which is based on waist circumference (WC), is an anthropometric parameter with decent predictive ability when measuring centripetal obesity. In this regard, the current study is an attempt to unravel the relationship between BSI and sympathovagal balance during exercise performed on two different instruments (treadmill and ergometer) by elite and amateur athletes. Methods It was an observational case-control study that included 30 elite and 120 amateur athletes. Symptom-limited exercise testing was performed by athletes on a motorized treadmill and ergometer in the sports physiology laboratory of a rural medical college in central India. Different anthropometric parameters like BSI and body surface area (BSA) were also recorded. Short-term HRV extracted fromelectrocardiogram (ECG) recordings was obtained using the Power Lab system and HRV analysis by LabChart software. Results The sympathovagal ratio, i.e., ratio of low frequency (LF) to high frequency (HF) in elite and amateur male populations showed a higher value than that in females, indicating a dominant sympathetic response in the males. There was a significant (p=0.042) positive correlation (r=0.24) between BSI and LF/HF Ratio in amateur females during treadmill exercise, whereas a significant (p=0.049) negative correlation (r=-0.27) was obtained in amateur males during ergometer exercise. Hence, increased weight and BSI were found to be associated with high sympathetic dominance, indicating a sympathovagal imbalance. Conclusion We attempted to explore the interaction between BSI and LF/HF during exercise performed on two different instruments (treadmill and ergometer) by elite and amateur athletes, which can help in testing the response of cardiac function to stress experienced during exercise. The study's uniqueness stems from discovering the relationship between BSI and HRV and how this relationship impacts sports performance. BSI measurement in athletes, both elite and amateur, allows for the assessment and forecasting of potential autonomic activity under exercise-induced stress by linking HRV with BSI.

An experimental study to diagnose coronary artery disease using five treadmill scores

Objectives: Exercise is the first step of a cardiovascular stress test, including electrocardiography (ECG) and blood pressure monitoring. Typically, a treadmill or bicycle is used to carry out the exercise for this stress test. Computer-derived criteria and a scoring system have been proposed and tested in hopes of improving the diagnostic accuracy of the exercise ECG for diagnosing coronary artery disease (CAD). Many treadmill scores have not been compared with one another in the same population, so questions remain concerning their diagnostic accuracy. The study aimed to correlate the diagnostic accuracy of ST segment response with various treadmill scores. Material and Methods: A total of 100 consecutive patients with suspected CAD referred for exercise testing at ACS Medical College and Hospital, Chennai, Tamil Nadu, between December 2021 and June 2022 were included in the study. The Institutional Review Board approved the study protocol at our institution, and all patients provided written informed consent. A treadmill test was conducted using commercially available equipment. All patients were subjected to symptom-limited exercise testing following the standard Bruce and modified Bruce protocols. A series of five scores were calculated using data collected from the patients to calculate the probability of CAD occurrence. Results: The study included 100 patients with an average age of 48.4 ± 1 years. Obesity (41%), hypertension (80%), diabetes (86%), current smokers (62%), family history of CAD (46%), and hypercholesterolemia (46%) were all observed in the study. The receiver operator characteristic (ROC) plot’s area under the curve (AUC) (standard error) for the Detrano score was 0.46 ± 0.59. This was significantly lower than the AUC of each treadmill score. The AUC of the ROC plots of the Duke treadmill score (DTS), veterans affairs (VA), and consensus scores were 0.47 ± 0.58, 0.63 ± 0.56, and 0.61 ± 0.57, respectively. Conclusion: The Morise score remains helpful in our study population for detecting CAD and determining risk strata. DTS and Detrano had comparable accuracy when calculated from intermediate and high probability scores and ST responses (44% and 43%, respectively). VA and consensus had lower accuracy than others (37% and 29%, respectively).

Extracellular volume is an independent predictor of peak cardiac power in asymptomatic patients with moderate-to-severe aortic stenosis

Abstract Funding Acknowledgements Type of funding sources: Other. Main funding source(s): The PRIMID study was funded by an NIHR fellowship (Post-Doctoral Fellowship supported by the National Institute for Health Research (NIHR-PDF 2011–04–51 Gerald P McCann.) Background Cardiac power (CP) describes the cardiac work done to maintain arterial pressure in the vasculature and peak CP is the ceiling of pumping performance the heart can achieve. Mean pressure gradient adjusted CP (MPG-CP) gives a more accurate representation of afterload in patients with aortic stenosis (AS) but its association with left-ventricular remodelling parameters is unknown. Purpose To establish the determinants of peak MPG-CP in asymptomatic patients with AS. Methods In this prospective, multi-centre observational study, asymptomatic patients with moderate to severe AS underwent echocardiography, cardiovascular magnetic resonance (CMR) imaging and cardiopulmonary exercise testing. Peak MPG-CP was calculated at peak exercise during an incremental symptom-limited exercise test on semi-supine ergometer, using the formula shown (Figure-1). Clinical and imaging univariable and multivariable associations of peak MPG-CP were assessed by linear regression. Results Peak MPG-CP was measured in 86 patients (mean age 66±12 years, 77% male, mean aortic valve area (AVA) 1.08±0.33 cm^2). On univariable analysis, peak MPG-CP was directly correlated with echocardiogram-measured AVA, peak pressure gradient, max velocity, and CMR-measured myocardial perfusion reserve (MPR), LV mass index (LVMI) and LV end-diastolic volume index (LVEDVI), and inversely correlated with extracellular volume (ECV) and NT-proBNP (Table-1). ECV was the only variable independently associated with peak MPG-CP regardless of which measure of AS severity was inputted in the multivariable model. Conclusions ECV, a marker of diffuse interstitial fibrosis, is an independent predictor of peak MPG-CP in asymptomatic patients with moderate-severe AS. Given ECV's role as a prognosticator, CP parameters may be important markers of subclinical disease and serve as surrogates for fibrotic burden and risk-stratification tools in asymptomatic AS.

Thirteen-Year Associations of Occupational and Leisure-Time Physical Activity with Cardiorespiratory Fitness in CARDIA.

Differential effects on fitness are hypothesized to contribute to the opposing health effects of leisure-time physical activity (LTPA) and occupational physical activity (OPA). As such, this study examined cross-sectional and longitudinal associations of fitness with LTPA and OPA. This study examined fitness associations with LTPA and OPA across 13 yr in the Coronary Artery Risk Development in Young Adults study (years 7 (baseline), 10, 15, and 20 (follow-up) examinations). Fitness was measured at baseline and follow-up via symptom-limited maximal graded exercise test (GXT) duration (in seconds), whereas LTPA and OPA were self-reported during each examination. Baseline and follow-up cross-sectional associations of LTPA (low, medium, high) and OPA (0, 1-6, and ≥6 months with OPA) with fitness were examined using linear regression. Longitudinal linear regression examined associations between 13-yr LTPA (low, medium, or high) and OPA (no, decreasing, or increasing) trajectories with fitness at follow-up, adjusted for baseline values. All models adjusted for center, sex, race, age, education, smoking history, alcohol intake, resting blood pressure, diabetes status, and body mass index. Stratified analyses examined associations by sex (female/male), race (Black/White), and LTPA groups. Compared with low, medium, and high LTPA were positively associated with fitness in all analyses ( P < 0.001). Reporting 1-6 or ≥6 months with OPA was negatively associated with fitness in cross-sectional follow-up models ( β = -15.6 and -15.4, respectively; P ≤ 0.01). Longitudinally, those with increasing OPA had lower follow-up fitness compared with no OPA ( β = -16.41, P < 0.01). Negative associations of OPA with fitness were not meaningfully different across sex and race groups. Significant LTPA-OPA interactions were observed ( P < 001). Physical activity research and public health promotion should consider domain-specific associations on cardiovascular health.

Effect of Coronary Sinus Reducer Implantation on Aerobic Exercise Capacity in Refractory Angina Patients—A CROSSROAD Study

Coronary sinus reducer (CSR) implantation is a new treatment option for patients with refractory angina pectoris. However, there is no evidence from a randomized trial that would show an improvement in exercise capacity after this treatment. The aim of this study was to evaluate the influence of CSR treatment on maximal oxygen consumption and compare it to a sham procedure. Twenty-five patients with refractory angina pectoris (Canadian Cardiovascular Society (CCS) class II–IV) were randomized to a CSR implantation (n = 13) or a sham procedure (n = 12). At baseline and after 6 months of follow-up, the patients underwent symptom-limited cardiopulmonary exercise testing with an adjusted ramp protocol and assessment of angina pectoris using the CCS scale and Seattle angina pectoris questionnaire (SAQ). In the CSR group, maximal oxygen consumption increased from 15.56 ± 4.05 to 18.4 ± 5.2 mL/kg/min (p = 0.03) but did not change in the sham group (p = 0.53); p for intergroup comparison was 0.03. In contrast, there was no difference in the improvement of the CCS class or SAQ domains. To conclude, in patients with refractory angina and optimized medical therapy, CSR implantation may improve oxygen consumption beyond that of optimal medical therapy.

Effect of hybrid cardiac rehabilitation using a smart device: a randomized controlled trial

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Korea National Institute of Health. Background Although cardiac rehabilitation (CR) has been proven to be effective in secondary prevention for patients with cardiovascular diseases, the actual participation in CR is still unsatisfactory. Because home-based CR provides better access to patients and is as effective as center-based CR, it is considered a promising alternative that can overcome various barriers impeding CR implementation. However, home-based CR has not garnered enough attention due to a lack of proper communication, concerns about unexpected adverse events caused by non-monitored exercises, and the absence of supporting insurance services. Purpose We utilized a smart ring with a photoplethysmography to monitor heart rate. Recorded data were stored on a website where the researchers could remotely access and check the uploaded measurements. This study aims to identify the clinical effects of hybrid CR by weekly telephone counseling based on the patients' actual physical activities obtained from the device. Methods Cardiovascular disease patients were educated on concrete methods of home-based CR, including the type, intensity, and time of exercise as well as precautions. They were also instructed to wear the device during exercise. The patients were randomly enrolled into two groups: intervention and observation groups. The patients of the intervention group were given weekly telephone counseling and encouraged to maintain optimal physical activities. In the observational group, only exercise data were recorded without additional interventions. Before and after three months of training, the results of the symptom-limited cardiopulmonary exercise test between the two groups were compared. Results A total of sixty-four patients were enrolled (thirty-two in each group). The subjects were 59.8 ± 9.0 years old and fifty-three (82.8%) were male. There were no significant differences in diagnosis and results of baseline symptom-limited cardiopulmonary exercise test between the two groups (Table 1). After three months of training, peak oxygen consumption was significantly improved in both groups. However, the improvement was greater in the intervention group compared to the observation group (Table 2). Conclusion Home-based CR using a smart device was effective in improving oxygen consumption. For greater effectiveness, proper monitoring and timely counseling by medical experts are likely to be necessary.

Impact of a cardio-oncology rehabilitation framework among high cardiovascular risk cancer survivors: results from the CORE trial

Abstract Funding Acknowledgements Type of funding sources: None. Background Cancer survivors are challenging patients, as they often present increased cardiovascular (CV) risk. In this background, cardio-oncology rehabilitation frameworks for specific cancer patients have been proposed. However, optimal program designs, as well as their overall safety and efficacy in different subsets of patients, are not fully ascertained. Purpose To assess the impact of a cardio-oncology rehabilitation based framework for cancer patients at increased CV risk, compared to a community-based exercise training (CBET), on cardiorespiratory fitness (CRF) and cardiovascular risk factor (CVRF) control. Methods The CORE study was a single-center, prospective, randomized controlled trial enrolling adult cancer survivors exposed to cardiotoxic cancer treatment (anthracycline, radiotherapy on thoracic wall, anti-human epidermal growth factor receptor-type 2 drugs) and/or with previous CV disease. Participants were randomized to an 8-week center-based CR program (CBCR) or CBET, twice a week. Primary endpoint was CRF (assessed by the VO2peak, derived from a symptom-limited cardiopulmonary exercise test, performed on a treadmill); secondary endpoints were physical activity [International Physical Activity Questionnaire (IPAQ)], psychosocial parameters [Hospital Anxiety and Depression Scale (HADS)], blood pressure, body composition, lipid profile and health literacy [Newest Vital Sign (NVS) questionnaire]. Results 80 patients were included (mean age 54.5±14,12, 61 women; 66% breast cancer, 27.5% lymphoma); 75 patients completed the intervention (CBCR N= 38; CBET N=37). There was a significant improvement in the CBCR compared to the CBET group in VO2peak (∆ +2.1±2.8 vs +0.8±2.5 mL.kg-1.min-1, p=0.033) and in the following outcomes: resting systolic blood pressure (p&amp;lt;0.0001); body mass index (p&amp;lt;0.0001), lean and fat body mass (p&amp;lt;0.0001), waist circumference (p&amp;lt;0.0001); total cholesterol (p =0.001), triglycerides (p =0.008) and LDL cholesterol (p =0.003); HADS Anxiety score (p =0.003) and Depression score (p =0.009), weekly physical activity levels (p&amp;lt;0.0001) and health literacy scores (p&amp;lt;0.0001). No major CV events were reported. Conclusion The CORE trial demonstrates superior results of a CBCR regarding CRF and CVRF control. Given the higher cardiovascular risk in several groups of cancer patients, our data provides novel insights into optimized preventive strategies in this complex patient population.

Single-cell sequencing of immune cells after marathon and symptom-limited cardiopulmonary exercise

Vigorous-intensity leisure-time physical activity, such as marathon, has become increasingly popular, but its effect on immune functions and health is poorly understood. Here, we performed scRNA-seq analysis of peripheral blood mononuclear cells (PBMCs) after a bout of symptom-limited cardiopulmonary exercise (CPX) test or marathon. Time-series single-cell analysis revealed the detailed series of landscapes of immune cells in response to short and long vigorous-intensity activities. Reduction of effective Tcells was observed with the cell migration and motility pathways enriched in circulation following marathon. Baseline values of PBMCs abundance were reached around 1h after CPX and 24h following marathon, but longer time was required for expression recovery of cytotoxicity genes. The ratio of effector/naive Tcells was found to change uniformly among the participants and could serve as a better indicator for exercise intensity than the CD4+/CD8+ Tcell ratio. Moreover, we identified time-dependent monocyte state transitions after marathon.

Correlation between Heart rate recovery and Left Atrial phasic functions evaluated by 2D speckle-tracking Echocardiography after Acute Myocardial infarction

BackgroundHeart rate recovery (HRR) in the exercise test is the index of cardiac autonomic system function and sympathovagal balance impaired in patients with myocardial infarction (MI). An instance is left atrial (LA) phasic function, which is impaired in such patients. In this study, we investigated the role of HRR in predicting LA phasic functions in patients with MI.MethodsThe present study recruited 144 consecutive patients with ST-elevation MI. A symptom-limited exercise test was performed about 5 weeks after MI, with echocardiography conducted just before the exercise test. The patients were divided into abnormal and normal HRR at 60 s (HRR60) and again into abnormal and normal HRR at 120 s (HRR120) after the exercise test. LA phasic functions, evaluated by 2D speckle-tracking echocardiography, were compared between the 2 groups.ResultsPatients with abnormal HRR120 had lower LA strain values and strain rates during the reservoir, conduit, and contraction phases, while those with abnormal HRR60 had lower LA strain values and strain rates during the reservoir and conduit phases. The differences were lost after adjustments for possible confounders, except for LA strain and strain rate during the conduit phase, in patients with abnormal HRR120.ConclusionsAbnormal HRR120 in the exercise test can independently predict decreased LA conduit function in patients with ST-elevation MI.

Maximal Exercise Improves the Levels of Endothelial Progenitor Cells in Heart Failure Patients.

The impact of exercise on the levels of endothelial progenitor cells (EPCs), a marker of endothelial repair and angiogenesis, and circulating endothelial cells (CECs), an indicator of endothelial damage, in heart failure patients is largely unknown. This study aims to evaluate the effects of a single exercise bout on the circulating levels of EPCs and CECs in heart failure patients. Thirteen patients with heart failure underwent a symptom-limited maximal cardiopulmonary exercise test to assess exercise capacity. Before and after exercise testing, blood samples were collected to quantify EPCs and CECs by flow cytometry. The circulating levels of both cells were also compared to the resting levels of 13 volunteers (age-matched group). The maximal exercise bout increased the levels of EPCs by 0.5% [95% Confidence Interval, 0.07 to 0.93%], from 4.2 × 10-3 ± 1.5 × 10-3% to 4.7 × 10-3 ± 1.8 × 10-3% (p = 0.02). No changes were observed in the levels of CECs. At baseline, HF patients presented reduced levels of EPCs compared to the age-matched group (p = 0.03), but the exercise bout enhanced circulating EPCs to a level comparable to the age-matched group (4.7 × 10-3 ± 1.8 × 10-3% vs. 5.4 × 10-3 ± 1.7 × 10-3%, respectively, p = 0.14). An acute bout of exercise improves the potential of endothelial repair and angiogenesis capacity by increasing the circulating levels of EPCs in patients with heart failure.

Abstract 31: Associations Between Cardiorespiratory Fitness (CRF) in Early Adulthood, Retention Through Midlife, and Heart Failure (HF) Stages: Findings From Coronary Artery Risk Development in Young Adults (CARDIA) Study

Introduction: Prior studies demonstrate that poor CRF in early adulthood is associated with adverse cardiac structure and function in midlife. The purpose of this study is to examine if higher early adulthood CRF and retention of CRF through midlife are associated with lower subsequent risk of subclinical or clinical HF. Methods: CARDIA participants with available data on CRF at baseline (Year [Y] 0: 1985-86), follow-up (Y7 or Y20), and HF staging data by Y30 were included. CRF was estimated using treadmill duration from a maximal, symptom-limited graded exercise test via modified Balke protocol. An adjusted linear mixed model was used to estimate treadmill duration when CRF assessment was missing at Y7 or 20. HF stages were defined using AHA HF staging criteria, including Stage 0 (no HF risk factors). Clinical HF was adjudicated by committee. Adjusted multinomial models tested associations between Y0 CRF and percent CRF retained through Y20 with HF stages at Y30, with Stage 0 as the reference. Interactions by the four race-sex groups were examined. Results: Of 2,565 individuals (25.1±3.5 y, 43% Black, 55% female), 30% (n=778), 37% (n=952), 32% (n=813), and 1% (n=32) were classified as Stages 0, A, B, or C/D by Y30 exam, respectively. Compared with Stage 0, every 1-minute increment higher CRF in early-adulthood was associated with a lower adjusted odds ratio of HF [Stage A: 0.72 (95% CI 0.68, 0.76), Stage B: 0.80 (95% CI 0.75, 0.84), Stage C/D 0.86 (95% CI 0.71, 1.04)]. Compared with Stage 0, every 1-standard deviation of % CRF retained at Y20 (midlife) was also associated with a lower odds of Stage A, B, and C/D HF at Y30 (Figure). A race-sex interaction was not observed (p-interaction 0.42). Conclusion: Higher early adulthood CRF, and greater retention of CRF through midlife, were associated with lower risk of developing subclinical or clinical HF. Strategies to maintain optimal CRF across the young adulthood to midlife transition may be important in prevention of HF.

Metabolomic, oxidative, and inflammatory responses to acute exercise in chronic obstructive pulmonary disease

BackgroundThere is currently a need to identify metabolomic responses to acute exercise in chronic obstructive pulmonary disease (COPD). ObjectiveWe investigated the metabolomic, oxidative, and inflammatory responses to constant (CE) and intermittent (IE) work rate exercises in COPD. MethodsSixteen males with COPD performed a symptom-limited incremental cycle exercise test (ICE). Metabolomic, oxidative, and inflammatory responses to CE and IE (based on the performance of ICE) were analyzed in the plasma. ResultsFructose-6-phosphate, 3-phosphoglyceric acid, l-carnitine, and acylcarnitines levels were significantly decreased, whereas alpha-ketoglutaric, malic, 2-hydroxybutyric, and 3-hydroxybutyric acids were increased, after CE and IE (p<0.05). Increases in citric, isocitric, and lactic acids, as well as decreases in pyruvic and oxalic acids, were only present with IE (p<0.05). Isoleucine was decreased after both exercises (p<0.05). We observed an increase in inosine-5′-diphosphate, uric acid, ascorbic acid, and pantothenic acid, as well as a decrease in 5-hydroxymethyluridine, threonic acid, and dehydroascorbic acid, after IE (p<0.05). Catalase, reduced glutathione, and total antioxidant status difference values for both exercises were similar (p>0.05). The change in glutathione peroxidase (GPx) with CE was more significant than that with IE (p = 0.004). The superoxide dismutase change was greater with IE than with CE (p = 0.015). There were no significant changes in inflammatory markers after exercise (p>0.05). ConclusionCE and IE cause isoleucine, l-carnitine, and acylcarnitine levels to decrease, whereas ketone bodies were increased, thus indicating the energy metabolism shift from carbohydrates to amino acid utilization and lipid metabolism in COPD. Compared with CE, IE produces significant changes in more metabolomics in terms of carbohydrates, lipids, amino acids, nucleotides, and vitamins. Acute CE and IE alter circulating GPx levels in COPD.

Cardiorespiratory fitness in adolescents and young adults with Klinefelter syndrome - a pilot study.

Klinefelter syndrome (KS) may be associated with a wide spectrum of phenotypic changes including endocrine, metabolic, cognitive, psychiatric and cardiorespiratory pathologies in adults. However, in adolescence the clinical phenotype of KS is not well described, especially regarding physical fitness. The present study reports on cardiorespiratory function in adolescents and young adults with KS. Adolescents and young adults with KS were recruited in a cross-sectional pilot study. Biochemical parameters of fitness including hormonal status, a body impedance analysis, the grip strength, the amount of physical activity at home for 5 days via trackbands and anamnestic parameters were assessed. In addition, participants underwent an incremental symptom-limited cardiopulmonary exercise test (CPET) on a bicycle ergometer. Nineteen participants with KS aged 15.90 ± 4.12 years (range: 9.00 - 25.00) participated in the study. Pubertal status was Tanner 1 (n = 2), Tanner 2 - 4 (n = 7) and Tanner 5 (n = 10). Seven participants received testosterone replacement therapy. Mean BMI z-score was 0.45 ± 1.36 and mean fat mass was 22.93% ± 9.09. Grip strength was age-appropriate or above normal. 18 participants underwent CPET with subnormal results for maximum heart rate (z-score -2.84 ± 2.04); maximum workload (Wattmax; z score -1.28 ± 1.15) and maximum oxygen uptake per minute (z- score -2.25 ± 2.46). Eight participants (42.1%) met the criteria for chronotropic insufficiency (CI). Data from track-bands showed sedentary behavior for 81.15% ± 6.72 of the wear time. A substantial impairment of cardiopulmonary function can be detected in this group of boys to young adults with KS, including chronotropic insufficiency in 40%. The track-band data suggest a predominantly sedentary lifestyle, despite normal muscular strength as assessed via grip strength. Future studies need to investigate the cardiorespiratory system and its adaption to physical stress in a larger cohort and in more detail. It is feasible that the observed impairments contribute to the avoidance of sports in individuals with KS and may contribute to the development of obesity and the unfavorable metabolic phenotype.

Does the Addition of Strength Training to a High-Intensity Interval Training Program Benefit More the Patients with Chronic Heart Failure.

Aerobic exercise, either continuous or high intensity interval training (HIIT), induces important benefits in chronic heart failure (CHF) patients. Resistance training has been also shown to be beneficial in CHF. However, data regarding combined aerobic exercise and muscle strength training is still limited. The aim of this study was to investigate whether adding strength training to a HIIT protocol within a cardiac rehabilitation (CR) program has a cumulative beneficial effect on the functional capacity (FC) and quality of life (QoL) in patients with CHF. Forty-four consecutive patients [35 males, ejection fraction (EF) 50%] with CHF under medication enrolled in a 36-session CR program and were randomized in two exercise groups; HIIT (HIIT group) or HIIT combined with strength training (high intensity interval training combined with strength training (COM) group). All patients underwent baseline and endpoint outcome measures of a symptom-limited maximal cardiopulmonary exercise testing (CPET), 1 repetition maximum (1RM) test, muscular endurance test, echocardiography, and Minnesota Living with Heart Failure Questionnaire (MLWHFQ). Most of the CPET indices, EF, 1RM test, muscular endurance and QoL were improved after the CR program in each exercise training group (p 0.05). However, COM group demonstrated a further improvement in chest muscle testing and workload at anaerobic threshold (AT) compared to HIIT group. An exercise-based CR program, consisted of either HIIT or HIIT combined with strength training, improves FC and QoL of patients with CHF. However, the addition of strength training to HIIT seems to have further beneficial effects on chest muscle strength and endurance, as well as workload at AT. The study was registered in ClinicalTrials.gov with number NCT02387411.

PREDICTED MAX HEART RATE SHOULD NOT BE USED FOR PATIENTS IN CARDIAC REHABILITATION

https://youtu.be/o3sLspfpDqs BACKGROUND A maximal exercise test is often not available for patients in cardiac rehabilitation (CR) and many programs determine a target heart rate (THR) using equations to estimate maximum heart rate (HRmax). The purpose of this study was to describe the % of patients in which a THR based on an estimated HRmax would result in a heart rate (HR) that is consistent with guidelines (i.e., 50%–80% HR reserve) in patients with heart disease (HD) on beta-blockade therapy. METHODS This was a secondary analysis of the iATTEND study; a randomized trial of facility-based only CR vs. hybrid CR. Subjects included in the present analysis had a history of myocardial infarction, coronary revascularization procedure, or heart failure; beta-blockade therapy; and sinus rhythm. Exclusion criteria were heart transplant, atrial fibrillation, implanted pacemaker, and exercise-induced ischemia. Measured HR reserve (maximum - rest) was determined from a symptom-limited maximal exercise test with gas exchange performed on a treadmill. Estimated HRmax was determined using (a) 220 age and (b) a published equation based on patients with HD with beta-blockade (HD BB; 164-0.72xage). % measured HR reserve associated with 60% and 85% estimated HRmax using each equation was compared to guideline recommended intensity of 50%–80% measured HR reserve. Paired sample t-tests were used to compare measured HRmax to the 2 estimates of HRmax. RESULTS Among 166 subjects (68% male; age= 59±11 yr [mean±SD]) measured HRmax was 133±21 min 1. Compared to measured, estimated HRmax using 220-age was significantly higher (161±11 min- 1; p&amp;lt;.001) and estimated HRmax using HD-BB was significantly lower (121±8 min-1; p&amp;lt;.001). At 60% of 220-age, 19% of subjects would have been provided a THR that was consistent with guidelines; 72% would have been too low. At 60% of HD-BB, 1% of subjects would have been provided a THR that was consistent with guidelines; 99% would have been too low. At 85% of 220-age, 16% of subjects would have been provided a THR that was consistent with guidelines; 84% would have been too high. At 85% of HD-BB, 36% of subjects would have been provided a THR that was consistent with guidelines; 15% would have been too high. CONCLUSION THR based on % estimated HRmax from 220-age and HD-BB do not provide an exercise training HR target that is consistent with guideline recommendations, thus should not be used to prescribe an exercise intensity in patients with HD on BB therapy.

Association Between the Redox State of Human Serum Albumin and Exercise Capacity in Patients With Cardiac Disease

The redox state of human serum albumin (HSA) is reported to be an oxidative stress biomarker; however, its clinical use in cardiac disease has not yet been examined. This study aimed to investigate the relation between the redox state of HSA and exercise capacity, which is a robust prognostic factor, in patients with cardiovascular disease. This cross-sectional study included outpatients with cardiac disease. Exercise capacity was assessed by peak oxygen consumption (peakVO2) measured using symptom-limited cardiopulmonary exercise testing. The high-performance liquid chromatography postcolumn bromocresol green method was used to part HSA into human nonmercaptalbumin (oxidized form) and human mercaptalbumin (HMA, reduced form). The fraction of human mercaptalbumin found in HSA (f[HMA]) was calculated as an indicator of the redox state of HSA. The association between peakVO2 and f(HMA) was examined using the Spearman correlation coefficient and multivariate linear regression analysis. A total of 70 patients were included (median age 76years; 44 men; median peakVO2 15.5ml/kg/min). The f(HMA) was positively correlated with peakVO2 (r=0.38, p <0.01). Even after controlling for potential confounders, this association remained in the multivariate linear regression analysis (standardized beta=0.24, p <0.05). We found a positive association between f(HMA) and peakVO2, independent of potential confounders in patients with cardiac disease, suggesting that f(HMA) may be a novel biomarker related to exercise capacity in cardiac disease. Longitudinal studies are required to further examine the prognostic capability of f(HMA), the responsiveness to clinical intervention, and the association between f(HMA) and cardiac disease.

Peak exercise oxygen uptake and changes in renal function in patients after acute myocardial infarction

BackgroundThe impact of exercise tolerance on renal function change after acute myocardial infarction (AMI) is not clear. ObjectivesThe present study aimed to elucidate the effect of peak exercise oxygen uptake (VO2) levels on longitudinal changes in renal function up to 1 year after onset of AMI. MethodsThis retrospective longitudinal study enrolled 198 AMI patients. Symptom-limited cardiopulmonary exercise testing was performed at completion of early Phase II cardiac rehabilitation, and peak VO2 levels were defined as the primary exposure factor. The estimated glomerular filtration rates (eGFRs) at baseline, 3 months, 6 months and 1 year were collected. Generalized estimating equation (GEE) models were used to test the longitudinal effect of peak VO2 levels on within-patient changes in eGFR. ResultsPatients were stratified into tertile groups (Low group, 12.3 ± 1.3 mL/kg/min; Mid group, 15.3 ± 0.7 mL/kg/min; and High group, 19.1 ± 2.3 mL/kg/min) according to peak VO2 levels. The slopes of eGFR over 1 year in the Low (p = 0.024) and Mid groups (p = 0.037) were lower compared to the High group. The Low group had a significantly higher odds ratio of experiencing rapid renal function decline than the High group (odds ratio, 2.87; p = 0.012). ConclusionsThere was a significant effect of lower peak VO2 on rapid decline in renal function after AMI. Our findings suggest that the coexistence of exercise intolerance may be a novel risk factor for rapid decline in renal function after AMI.

Exercise-induced ventricular arrythmia in asymptomatic patients with Mitral Valve Prolapse

Abstract Introduction Mitral Valve Prolapse (MVP) is associated with complex ventricular arrythmia (VA) and sudden cardiac death but risk stratification remains unclear. Exercise induces an hyperadrenergic state and could trigger VA, however, data on exercise-induced VA (EIVA) in MVP patients are scarce. Objective To describe EIVA prevalence, origin, characteristics and associated features in MVP patients. Methods In this observational prospective study, 64 MVP asymptomatic patients (58±14 years, 41 men) with mild to severe mitral regurgitation (MR) and without left ventricular (LV) dysfunction, underwent echocardiography and symptom-limited exercise testing. Continuous 12-lead ECG monitoring was performed throughout testing. Severe EIVA was defined as ventricular triplets, sustained or non-sustained ventricular tachycardia (NSVT) or ventricular fibrillation. Results All patients exercised at maximal intensity until exhaustion. EIVA was observed in 54 (84%) subjects including 12 (19%) patients with severe EIVA (7 triplets, 5 NSVT). Severe EIVA originated mainly from the mitral apparatus (all but one) and occurred at high exercise intensity (median 90% of predicted workload) or during early recovery phase. Compared to the rest of the cohort the patients with severe EIVA had similar resting ECG characteristics, similar LV dimension and function, similar degree of MR and mitral apparatus morphology. Finally, severe EIVA was not associated with an alteration of exercise tolerance. Conclusion Exercise frequently unmasks ventricular arrythmia in patients with MVP. EIVA appears not linked to MVP features nor to exercise tolerance and seems to provide additional phenotyping information that could be linked to prognosis. Funding Acknowledgement Type of funding sources: None.

Low-dose dopamine improves ventilatory efficiency during exercise in heart failure with preserved ejection fraction through inhibition of tonic activity of peripheral chemoreceptors

Abstract Introduction Peripheral chemoreceptors (PChRs) play an important role in adequate oxygenation by 1) maintaining baseline ventilation (tonic activity) and 2) providing hyperventilation in response to acute hypoxia (reflexia). It has been previously shown that in patients with heart failure with reduced ejection fraction hypertonicity and/or hyperreflexia of PChRs contribute to exercise intolerance (ExIn). It is unknown whether similar mechanisms are present in heart failure with preserved ejection fraction (HFpEF) and which component of PChR functionality has a decisive role in this matter. Purpose The aim of this study was to evaluate the role of PChRs in ExIn in patients with HFpEF. Methods All patients underwent assessment of PChRs which included measurements of: 1) tonic activity (TA, decrease in ventilation following pharmacological inhibition of PChRs), 2) reflex response (RR; an increase in ventilation in the response to acute hypoxia). The inhibition of PChRs was achieved with low-dose dopamine infusion (3 μg kg–1 min–1) and the acute hypoxia was produced with brief nitrogen gas administrations. Enrolled patients underwent symptom-limited cardiopulmonary exercise test using cycle ergometer from which peak oxygen consumption (peakVO2) and the slope relating ventilation to carbon dioxide (VE/VCO2 slope) were derived. All measurements (including PChRs' function tests and cardiopulmonary exercise test) were performed twice in a randomized, double-blinded and placebo-controlled manner (dopamine vs normal saline). Results We included 12 stable patients with HFpEF (age: 73±7 years, LVEF: 58±3%). During exercise the inhibition of PChRs with dopamine resulted in the improvement (decrease) in VE/VCO2 slope comparing to placebo (36±3.6 vs 34.3±3.7, p=0.04) but no change regarding peakVO2. There was a correlation between TA and relative magnitude of improvement in VE/VCO2 following PChRs inhibition (R=0.76, p=0.005). We also found a trend for correlation between RR and VE/VCO2 measured during placebo (R=0.56, p=0.059). There was no correlation between TA and RR (p=0.24). Conclusion Both TA and RR of PChRs are involved in ventilatory inefficacy during exercise in HFpEF – but in different ways. While augmented RR is likely an indicator of high VE/VCO2, the elevated TA indicates the magnitude of the improvement in exercise tolerance following PChRs deactivation. Thus, further interventions aimed at the modulation of PChRs should enroll patients based on TA rather than RR. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Science Centre, PRELUDIUM grant