Symptom-limited Maximal Exercise Test Research Articles

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.

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.

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.

Prescribing and Self-Regulating Heated Water-Based Exercise by Rating of Perceived Exertion in Older Individuals With Hypertension.

We aimed to analyze the usefulness of the 6-20 rating of perceived exertion (RPE) scale for prescribing and self-regulating high-intensity interval (HIIE) and moderate-intensity continuous (MICE) aerobic exercise performed in a heated swimming pool (32°C). Fifteen older individuals (65 ± 3years) treated for hypertension underwent a symptom-limited maximal graded exercise test to determine their heart rate at anaerobic threshold, and respiratory compensation point. On different days, participants were randomized to HIIE (walking/jogging between 11 and 17 of RPE; 25min) and MICE (walking at 11-13 of RPE; 30min). Heart rate during the low-intensity intervals of HIIE and MICE remained below the graded exercise test's heart rate at anaerobic threshold (-7 ± 18bpm/-16 ± 15bpm) and respiratory compensation point (-18 ± 18bpm/-30 ± 16bpm), respectively, and maintained in the aerobic training zone during the high-intensity intervals of HIIE (+8 ± 18bpm/-4 ± 19bpm). The RPE scale at 15-17 is a useful tool for prescribing and self-regulating heated water-based HIIE and may have important implications for water-based exercise in older individuals with hypertension.

Energy expenditure and glucose-lowering effect of different exercise modalities in diabetes mellitus

ObjectivesHypoglycaemia is a serious complication of exercise in patients with type 2 diabetes mellitus (T2DM). The aim of this study was to test energy expenditure and the degree of the glucose-lowering effect of different exercise modalities. DesignCross-sectional study ParticipantsThis study included 44 patients {35 women and nine men, mean age 51 [standard deviation (SD) 5] years} with T2DM [mean HbA1c 7% (SD 1%)]. Main outcome measuresStandardised exercise tests for walking, running and cycling were performed using the 6-minute walk test (6MWT), incremental shuttle walk test (ISWT), and symptom-limited maximal cycle exercise test, respectively. Energy expenditure was assessed with a multisensory accelerometer. Change in capillary glucose levels (∆glucose) was measured before and after each exercise modality. Results∆Glucose was lower in the 6MWT {median 14 [interquartile range (IQR) 22] mg/dl} than in the ISWT [median 18 (IQR 23) mg/dl; median difference 7 mg/dl, 95% confidence interval (CI) of the difference 3–11] and the cycle test [median 18 (IQR 24) mg/dl; median difference 7 mg/dl, 95% CI 0–16]. Energy expenditure was lower during the 6MWT [median 41 (IQR 18) Kcal] compared with the ISWT [median 51 (IQR 23) Kcal; median difference 11 Kcal, 95% CI 6–16] and the cycle test [median 44 (IQR 25) Kcal; median difference 6 Kcal, 95% CI 0–13]. ConclusionsEnergy expenditure and corresponding glucose-lowering effect during exercise in patients with T2DM can be predicted from the results of an exercise test. The type of exercise is related to the risk of hypoglycaemia. Walking is associated with the lowest energy expenditure and risk of hypoglycaemia, while cycling and running/jogging cause higher energy expenditure and greater reductions in glucose in patients with T2DM. Contribution of the paper•Energy expenditure and risk of hypoglycaemia during exercise can be predicted by exercise tests.•The intensity and type of exercise are related to the risk of hypoglycaemia.•The change in glucose level was greater for running and cycling than for walking.

Cardiorespiratory Fitness in Adults Aged 18 to 34 Years and Long-Term Pericardial Adipose Tissue (from the Coronary Artery Risk Development in Young Adults Study)

Pericardial adipose tissue (PAT), an ectopic adipose depot surrounding the coronary arteries, is a pathogenic risk marker for cardiometabolic disease; however, the association between cardiorespiratory fitness (CRF) and PAT is unclear. Young adults (n=2,614, mean age 25.1 years, 55.8% women, and 43.8% Black at baseline [1985 to 1986]) from the Coronary Artery Risk Development in Young Adults study were included. Maximal CRF was estimated at baseline, examination year 7 (1992 to 1993) and year 20 (2005 to 2006), using a symptom-limited maximal treadmill exercise test (duration in minutes) among those achieving ≥85% of age-predicted maximal heart rate. PAT volume (ml) was quantified at examination year 15 (2000 to 2001) and year 25 (2010 to 2011) using computed tomography. Multivariable linear and linear mixed regressions with covariates (sociodemographics, cardiovascular disease risk factors, inflammation, waist circumference) from baseline, year 7, and/or year 20 were used. Separate multivariable regression models revealed inverse associations of CRF at baseline, year 7, or year 20 with PAT at year 25 in fully adjusted models (all p <0.001). The linear mixed model showed that a 1-minute increase in treadmill exercise test duration over 20 years was associated with 1.49 ml lower subsequent PAT volume (p <0.001). In conclusion, findings suggest that higher CRF is inversely associated with subsequent PAT volume. Strategies to optimize CRF may be preventive against excessive PAT accumulation with age.

Cardiorespiratory fitness and electroanatomical remodelling in patients with atrial fibrillation

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Atrial fibrillation (AF) is the most common clinically-relevant arrhythmia. Its initiation and maintenance is linked to the presence cardiovascular risk factors such as hypertension and obesity. Higher cardiorespiratory fitness (CRF) has been associated with a better prognosis. However, specific electroanatomical features associated with baseline CRF have not been described. Purpose Compare electroanatomical substrate across exercise capacity levels in patients with AF Methods Patients referred for de novo AF radiofrequency ablation at the Centre for Heart Rhythm Disorders from August 2017 until June 2020 were screened for inclusion and CRF was evaluated in metabolic equivalents (METs) by a symptom-limited maximal treadmill exercise test using the standard Bruce protocol prior to ablation. Predicted CRF was calculated based on established equations and patients were categorized according to the percentage of predicted CRF achieved; low (&amp;lt;85%), adequate (85-100%) and high (&amp;gt;100%). Total mean and regional peak-to-peak bipolar voltages, percent of low voltage areas (% LVA), conduction velocity (CV) and percent of complex fractionated electrograms (% CFE) in sinus rhythm were compared across groups. Results There were no between-group differences in baseline characteristics, medication use or echocardiographic features. Total mean voltage was significantly lower in the low CRF group compared to both adequate and high CRF. Compared to the high CRF group, roof (3.25 ± 1.2 mV vs 1.9 ± 1.3 mV, p &amp;lt; 0.05), posterior (3.8 ± 1.8 mV vs 1.7 ± 0.9 mV, p &amp;lt; 0.001) and inferior mean voltages (3.4 ± 2 mV vs 1.6 ± 0.7 mV, p &amp;lt; 0.05) were significantly lower in the low CRF group (figure 1A). Furthermore, compared with the adequate CRF group, mean voltages were significantly lower in the posterior (3.7 ± 1.5 mV vs 1.7 ± 0.9 mV, p &amp;lt; 0.001), inferior (3.4 ± 1 mV vs 1.6 ± 0.7 mV, p &amp;lt; 0.001) and lateral (4.2 ± 2.2 mV vs 2.1 ± 1.4 mV, p &amp;lt; 0.05) walls of the low CRF group. Anterior and septal mean voltages were not significantly different across CRF groups (P for trend = 0.07, 0.3 and 0.15, respectively). Conduction velocities were not significantly different across groups. The inferior %LVA was significantly higher in the low CRF (5.6 ± 6%) compared to adequate CRF group (23 ± 18%) (p &amp;lt; 0.05) (figure 1B). Total and regional % CFE was higher in the low CRF compared to adequate and high CRF. Conclusion Participants in the lower baseline CRF category showed significant reductions in regional voltages along with higher fractionation with preserved conduction velocities. Research on the effect of physical activity and CRF on left atrial arrhythmogenic substrate is required. Abstract Figure. Global and regional mV and % LVA by CRF

A cardiac rehabilitation program increases the acute respond of endothelial progenitor cells after maximum exercise in patients with chronic heart failure

Abstract Background Chronic heart failure (CHF) remains a leading cause of morbidity and mortality and it is characterized by vascular endothelial dysfunction. During the last decades, endothelial progenitor cells (EPCs) are being used as an index of the endothelium restoration potential, therefore reflecting the vascular endothelial function. Exercise training has been shown to stimulate the mobilization of EPCs at rest in CHF patients. However, the effect of exercise training on the acute respond of EPCs after maximum exercise in CHF patients remains unknown. Purpose The purpose of the study was to assess the effect of a cardiac rehabilitation (CR) program on the acute respond of EPCs after maximum exercise in patients with CHF. Methods Forty-four consecutive patients (35 males) with stable CHF [mean±SD, Age (years): 56±10, BMI (kg/m2): 28.7±5.2, EF (%): 33±8, Peak VO2 (ml/kg/min): 18.4±4.4, Peak work rate (watts): 101±39] enrolled a 36-session CR program based on high-intensity interval exercise training. All patients underwent an initial symptom limited maximal cardiopulmonary exercise testing (CPET) on an ergometer before the CR program and a final maximal CPET after the CR program. Venous blood was drawn before and after each CPET. Five circulating endothelial populations were identified and quantified by flow cytometry; CD34+/CD45-/CD133+, CD34+/CD45-/CD133+/VEGFR2, CD34+/CD133+/VEGFR2, CD34+/CD45-/CD133- and CD34+/CD45-/CD133-/VEGFR2. EPCs values are expressed as cells/million enucleated cells in medians (25th-75th percentiles). Results The acute mobilization of EPCs after the final CPET was higher than after the initial CPET in 4 out of 5 circulating endothelial populations. Most specifically, difference of the acute mobilization of CD34+/CD45-/CD133+ cells [initial CPET: 25 (15–46) vs final CPET: 49 (26–71), p=0.002], CD34+/CD45-/CD133+/VEGFR2 cells [initial CPET: 3 (2–5) vs final CPET: 8 (5–12), p&amp;lt;0.001], CD34+/CD45-/CD133- cells [initial CPET: 129 (52–338) vs final CPET: 250 (129–518), p=0.03] and CD34+/CD45-/CD133-/VEGFR2 cells [initial CPET: 2 (1–4) vs final CPET: 6 (3–9), p&amp;lt;0.001] increased after the final CPET. The acute mobilization of CD34+/CD133+/VEGFR2 cells [initial CPET: 3 (−1–7) vs final CPET: 5 (0–15), p=0.441] did not differ between the 2 CPETS. Conclusion A 36-session cardiac rehabilitation program increases the acute respond of endothelial progenitor cells after maximum cardiopulmonary exercise training in patients with chronic heart failure, therefore indicating the beneficial effect of exercise training on the vascular endothelial function. Funding Acknowledgement Type of funding source: Public grant(s) – EU funding. Main funding source(s): Co-financed by Greece and the European Union (European Social Fund- ESF) through the Operational Programme “Human Resources Development, Education and Lifelong Learning” in the context of the project

The Predictive Value Of The Sf-36 Questionnaire In Determining CPET Performance In Patients With ME/CFS

INTRODUCTION: Patients diagnosed with Myalgic Encephalomyelitis (ME/CFS) tend to have difficulties with higher-intensity exercise, and usually show diminished maximal exercise capabilities when compared to their sedentary healthy counterparts (sHC). Thus, it is important to find new ways to identify patients most at risk for diminished exercise performance as soon as possible. PURPOSE: The present study seeks to determine the predictive validity of the Short Form Health Questionnaire (SF-36) and its subscales as a non-exercise component in patient evaluation. METHODS: 18 male patients diagnosed with ME/CFS (Age: 39.2 ± 12.8 years) and 18 male sedentary healthy controls (Age: 39.9 ± 13.4 years) were asked to fill out the SF-36 health survey before participating in a symptom-limited maximal exercise test (CPET). CPET was performed on a cycle ergometer, and initial resistance was set at 30 Watts with a 30 Watt increase every 2 minutes. Subjects were asked to maintain a cycling cadence of 60-70 RPM for as long as possible, or until they experienced any of the predetermined symptoms. Maximal exercise data and veniality efficiency measures were recorded and used in correlative analyses. RESULTS: Significant differences were observed between ME/CFS and sHC in all relevant subscales of the SF-36 (p < 0.005 in all cases). The Physical Functioning, Vitality and Physical Health subscales were all positively correlated with maximal oxygen uptake (VO2 Max) in the ME/CFS group (r = 0.67, p <0.005; r = 0.59, p <0.05; and r = 0.65, p < 0.005 respectively), but showed poor correlations in the sHC group (r = 0.28, p = 0.24; r = 0.16, p = 0.51; r = 0.11, p = 0.65 respectively). Although there were significant differences in VE/VCO2 slopes between the groups (p < 0.05), neither group showed strong correlations between and subscales and ventilatory efficiency. CONCLUSIONS: The SF-36 and its subscales showed strong correlations with maximal exercise performance in subjects diagnosed with ME/CFS. These results were not observed in sHC, possibly due in part to the large percentage of “perfect” scores recorded in this group. While the SF-36 did not show any significant correlations with inter-test ventilatory efficiency measures, it might still hold some value in predicting outcomes of maximal CPETs in subjects with diminished exercise capacity.

Subclinical Inflammation Is Associated With Reductions in Muscle Oxygenation, Exercise Capacity and Quality of Life in Adults With Type 2 Diabetes

ObjectivesExercise capacity is related to both morbidity and mortality in patients with type 2 diabetes (T2DM). The aim of this study was to investigate the relationship between subclinical inflammation level, exercise capacity, muscle oxygenation and quality of life in T2DM. MethodsThis study includes 28 patients with T2DM (mean age, 51.5±5.0 years; male-to-female ratio, 6:22). Exercise capacity was evaluated using an incremental symptom-limited maximal exercise test on a bicycle ergometer. Muscle oxygenation was investigated using a wearable lactate-measuring device. Diabetes-specific quality of life was assessed using the Diabetes Quality of Life Questionnaire (DQOL). Subclinical inflammation was assessed using C-reactive protein (CRP) levels. ResultsCRP level was negatively correlated with peak workload during the test (r=–0.588, p=0.002), muscle oxygenation (r=–0.465, p=0.019) and the psychological impact of treatment subscale of the DQOL (r=–0.540, p=0.017), and positively correlated with body mass index (r=0.519, p=0.008), waist circumference (r=0.426, p=0.038) and fat percentage (r=0.573, p=0.004). There was no correlation between CRP and fasting blood glucose or glycated hemoglobin level (p>0.05). Peak workload was inversely related to fat percentage (r=–0.467, p=0.016) and the DQOL worry about the future impact of diabetes subscale (r=–0.501, p=0.021). ConclusionsIn our study, subclinical inflammation negatively affected muscle oxygenation, exercise capacity and quality of life independently of glycemic indicators. Our findings suggest that the degree of glycemic control is insufficient to explain lower exercise capacity. Further studies are needed to investigate subclinical inflammation-reducing interventions in T2DM.

P753Exercise has similar beneficial effect in the mobilization of endothelial progenitor cells in patients with chronic heart failure of different severity

Abstract Introduction Vascular endothelial dysfunction is an underlying pathophysiological feature of chronic heart failure (CHF). Exercise has been shown to stimulate the mobilization of endothelial progenitor cells (EPC) in healthy populations. EPC contribute to the regeneration of the inflammatory endothelium and promote neovascularization. Purpose The purpose of the present study was to investigate the mobilization of EPC between CHF patients with different severity after a 36-session exercise training program. Methods Thirty eight consecutive patients (32 ♂, 6 ♀) with stable CHF [mean±SD, age (years): 56±10, EF (%): 32±9, peak VO2 (ml/kg/min): 18.1±4.1] enrolled a 36-session exercise training program. All patients underwent a symptom limited maximal cardiopulmonary exercise testing (CPET) on a cycle ergometer before and after the training program. Venous blood was sampled before and after each CPET. Five endothelial circulating populations were quantified by flow cytometry (Table 1). Patients were divided in severity groups according to the median values of peak VO2, predicted peak VO2, VE/VCO2 slope and EF. EPC values are expressed as “cells/million enucleated cells” in medians (25th, 75th percentiles). Results In all patients, rehabilitation showed a statistical significant effect as well as a significant acute effect in all endothelial circulating populations (p&lt;0.001). Although there was statistical significant mobilization of endothelial circulating populations within each severity group (groups separated by peak VO2), no differences were observed between groups (p&gt;0.05, Table 1). Similar results were also shown for the rest of CPET parameters and EF. Cellular populations in severity groups Endothelial cellular populations Peak VO2 &lt;18 ml/kg/min Peak VO2 ≥18 ml/kg/min Before rehabilitation After rehabilitation Before rehabilitation After rehabilitation Before CPET After CPET Before CPET After CPET Before CPET After CPET Before CPET After CPET CD34+/CD45–/CD133+ 54 (24–74) 90 (40–104)* 96 (54–120) 154 (100–169)* 37 (16–66) 60 (33–93)* 79 (46–106) 122 (96–159)* CD34+/CD45–/CD133+/VEGFR2 1 (1–3) 3 (2–8)* 8 (4–9) 14 (10–19)* 2 (1–3) 4 (3–8)* 5 (4–7) 13 (9–16)* CD34+/CD133+/VEGFR2 13 (8–18) 13 (9–25) 22 (16–31) 27 (14–38) 10 (7–19) 14 (9–20)** 16 (13–37) 22 (15–62)** CD34+/CD45–/CD133– 186 (131–368) 494 (202–640)* 431 (301–564) 738 (590–921)* 214 (150–270) 306 (233–575)* 434 (277–835) 740 (524–1588)* CD34+/CD45–/CD133–/VEGFR2 2 (1–2) 3 (2–5)* 4 (3–5) 10 (9–14)* 1 (1–1) 3 (2–5)* 4 (2–8) 9 (7–12)* Differences within groups *p&lt;0.001, **p&lt;0.05. Conclusion A 36-session training program stimulates the long term mobilization of EPC in CHF patients. This mobilization seems to be similar in all patients irrespective of their severity. The clinical relevance of these findings and the potential mechanisms need further investigation. Acknowledgement/Funding Greece and the European Union (European Social Fund-ESF) through the Operational Programme “Human Resources Development, Education, Lifelong Learning”

Mediating effects of exercise capacity on the association between physical activity and health-related quality of life among adolescents with complex congenital heart disease.

There is little evidence on interrelationships between physical activity, sedentary behaviors, and health-related quality of life (HRQOL) among adolescents with congenital heart disease (CHD). We hypothesized that exercise capacity would have a mediating effect on the associations of either physical activity or sedentary behavior with HRQOL. Adolescents with complex CHD (n = 111) were consecutively recruited from an outpatient clinic in a general hospital in South Korea. Physical activity and sedentary behavior were assessed using the global physical activity questionnaire. Exercise capacity was directly measured by peak oxygen uptake using a symptom-limited maximal treadmill exercise test. HRQOL was evaluated by both adolescents and their parents using the Pediatric Quality of Life Inventory questionnaire. The self-reported and parent proxy-reported HRQOL were positively associated with physical activity (ß = 0.16, P = .003; ß = 0.12, P = .049) and exercise capacity (ß = 0.63, P < .001; ß = 0.66, P < .001), but not with sedentary behavior in adjusted regression models. When both variables were entered in the same regression models, only exercise capacity remained significantly associated with the self-reported (ß = 0.50, P = .008) and parent proxy-reported HRQOL (ß = 0.62, P = .003). Exercise capacity acted as a full mediator variable on the relationship between physical activity and HRQOL (P < .05 for both). The present findings suggest that exercise capacity mediates the association between physical activity and HRQOL, highlighting the importance of improving exercise capacity to potentially enhance HRQOL in adolescents with complex CHD.

The Role of Dietary Patterns in the Contribution of Cardiorespiratory Fitness in Community-Dwelling Older Chinese Adults in Hong Kong

ObjectiveWe examined the influence of various dietary patterns on cardiorespiratory fitness (CRF) expressed as peak oxygen uptake (VO2peak), taking into account demographics and lifestyle risk factors. DesignProspective cohort study. Participants and methodsWe conducted multivariate linear regression analyses using available data from a cohort of community-dwelling older Chinese adults (752 men, 483 women) in Hong Kong. Baseline interviewer-administered questionnaires covered dietary intake estimation and dietary pattern generation from the food frequency questionnaire, demographic and lifestyle factors, self-reported medical history, as well as frailty status. VO2peak at the 7-year follow-up was measured using symptom-limited maximal exercise testing on an electrically braked bicycle ergometer. ResultsIn men, baseline Diet Quality Index–International (DQI-I) score (β = 0.044, P = .013) and Okinawan diet score (β = 0.265, P = .014) was independently associated with age-adjusted VO2peak at the 7-year follow-up. The significant association was only retained for the Okinawan diet score in the multivariate adjusted model (β = 0.227, P = .039). Dietary pattern scores including the Dietary Approaches to Stop Hypertension (DASH) score, Mediterranean-DASH Intervention for Neurodegenerative Delay Diet score, Mediterranean Diet Score, and 3 other pattern scores derived by factor analysis were not associated with VO2peak. In women, none of the dietary pattern scores at baseline was associated with VO2peak in both the age-adjusted and multivariate-adjusted models. Conclusions/ImplicationsA higher Okinawan diet score was associated with a higher 7-year CRF in community-dwelling Chinese older men. Further studies are warranted to examine the underlying mechanisms on how the Okinawan diet influences CRF.

Cardiorespiratory Fitness and Cognition: Longitudinal Associations in the FINGER Study.

Previous studies have found positive associations between cardiorespiratory fitness (CRF) and cognitive performance in older people but data are inconsistent and have methodological limitations. Our aim was to study the longitudinal associations of CRF with executive functions, processing speed and memory as well as with the overall cognitive function in older people at risk for cognitive impairment. Participants (n = 421), mean age 69.0, were a sub-sample of The Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER). To be eligible, individuals were required to be 60-77 years old with a CAIDE (Cardiovascular Risk Factors, Aging and Dementia) Dementia Risk Score of at least 6 points and cognition at mean level or slightly lower than expected for age. CRF was assessed as peak oxygen uptake (VO2peak, L/min) measured directly in a symptom-limited maximal exercise test on cycle ergometer at baseline and at 24 months. Cognitive performance was assessed using an extensive neuropsychological test battery (NTB) at baseline and at 24 months. NTB data were standardized to Z scores, and analyzed with the linear mixed model. Over two years, VO2peak was associated with NTB total score (β= 0.12, p = 0.01), executive functions (β= 0.16, p = 0.01), and processing speed (β= 0.25, p < 0.001), but not with memory (β= 0.11, p = 0.12). Over two years follow-up, CRF was associated with executive functions and processing speed, and was related also to the overall cognitive function.

Endothelial dysfunction and cellular repair in heart failure with preserved ejection fraction: response to a single maximal exercise bout

Endothelial dysfunction and cellular repair in heart failure with preserved ejection fraction: response to a single maximal exercise bout

Prognostic value of the heart rate profile during exercise in patients with atrial fibrillation.

Aims This study aimed to investigate the correlation of heart rate profile during exercise with exercise capacity and heart failure occurrence in patients with atrial fibrillation compared with patients with sinus rhythm. Methods We analyzed 2231 patients (atrial fibrillation: n = 321, sinus rhythm: n = 1910) who underwent a symptom-limited maximal cardiopulmonary exercise test at our institute. Their heart rate profile during exercise was assessed using peak heart rate and chronotropic response; (peak heart rate-resting heart rate)/(220-age-resting heart rate). The endpoint was the occurrence of heart failure events, defined as hospitalization for heart failure or heart failure-related death. Results There were significant positive correlations of peak heart rate and chronotropic response to peak oxygen consumption, both in atrial fibrillation and sinus rhythm. During a median follow-up period of 1262 (interquartile range 974-2921) days, 117 (5.2%) heart failure events were observed. Multivariate analyses showed that peak heart rate and chronotropic response were statistically significant predictors of heart failure events both in atrial fibrillation (peak heart rate: heart rate 0.975, p = 0.002, chronotropic response: heart rate 0.196, p = 0.003) and in sinus rhythm (peak heart rate: heart rate 0.988, p = 0.036, chronotropic response: heart rate 0.347, p = 0.020). Bivariate models showed that compared with chronotropic response, peak heart rate was a stronger predictor of heart failure in atrial fibrillation, whereas the finding was reversed in sinus rhythm. Conclusion The exercise- heart rate profile was significantly related to exercise capacity and future heart failure events, regardless of rhythm. However, the impacts of peak heart rate and chronotropic response on the endpoint varied according to the cardiac rhythm.

Relationship between the prognostic value of ventilatory efficiency and age in patients with heart failure.

Background Ventilatory efficiency decreases with age. This study aimed to investigate the prognostic significance and cut-off value of the minute ventilation/carbon dioxide production (VE/VCO2) slope according to age in patients with heart failure. Methods and results We analysed 1501 patients with heart failure from our observational cohort who performed maximal symptom-limited cardiopulmonary exercise testing and separated them into three age groups (≤55 years, 56-70 years and ≥71 years) in total and according to the three ejection fraction categories defined by European Society of Cardiology guidelines. The endpoint was set as heart failure events, hospitalisation for heart failure or death from heart failure. The VE/VCO2 slope increased with age. During the median follow-up period of 4 years, 141 heart failure (9%) events occurred. In total, univariate Cox analyses showed that the VE/VCO2 slope (cont.) was significantly related to heart failure events, while on multivariate analysis, the prognostic significance of the VE/VCO2 slope (cont.) was poor, accompanied by a significant interaction with age ( P < 0.0001). The cut-off value of the VE/VCO2 slope increased with the increase in age in not only the total but also the sub-ejection fraction categories. Multivariate analyses with a stepwise method adjusted for estimated glomerular filtration rate, peak oxygen consumption, atrial fibrillation and brain natriuretic peptide, showed that the predictive value of the binary VE/VCO2 slope separated by the cut-off value varied according to age. There was a tendency for the prognostic significance to increase with age irrespective of ejection fraction. Conclusion The prognostic significance and cut-off value of the VE/VCO2 slope may increase with advancing age.

P6-4 - Inverse Relationship Between Hemoglobin Oxygen Saturation Measured by Pulse Oximetry and Exercise Capacity in the Patients With Heart Failure

Background: Exercise capacity (EC) is a key prognostic factor in the patients with heart failure (HF). Peak oxygen consumption (peak VO2) measured by maximal symptom-limited cardiopulmonary exercise test (CPET) is the most objective method to determine EC. Hemoglobin oxygen saturation measured by pulse oximetry (SpO2) is a simple tool to evaluate oxygenation. The relationship between SpO2 at rest and EC is unclear. Purpose: To investigate the relationship between SpO2 at rest and EC measured by maximal symptom-limited CPET in the patients with HF. Methods: We examined the association between SpO2 and EC among 46 patients with HF (age 54 ± 13, male 76%) who underwent maximal symptom-limited CPET. Results: Peak VO2/weight and peak respiratory exchange ratio were 16.2 ± 5.6 mL⋅min−1⋅kg−1 and 1.2 ± 0.1, respectively. SpO2 at rest inversely correlated with peak VO2/weight (r = −0.43, P = .003). Compared with the patients who had preserved EC (peak VO2/weight > 11.0 mL⋅min−1⋅kg−1, n = 39), the patients who had low EC (peak VO2/weight < 11.0 mL⋅min−1⋅kg−1, n = 7) showed significantly higher SpO2 at rest (99.0 ± 0.8 vs 98.0 ± 1.6%, P = .03). Multiple regression analysis revealed that higher SpO2 at rest (β = −0.29, P = .006), age, BMI and lower hemoglobin, sodium are independent predictors of lower peak VO2/weight. Conclusion: In patients with HF, higher SpO2 at rest may detect lower EC.

The Effect of Physical Activity and Cardiorespiratory Fitness on All-Cause Mortality in Hong Kong Chinese Older Adults.

It is unclear whether physical activity (PA) could predict all-cause mortality independently of cardiorespiratory fitness, and there are relatively few studies evaluating the combined effect of PA and cardiorespiratory fitness on mortality. We invited 1,242 Chinese older adults aged 69-94 years from the MrOs and MsOs cohort (Hong Kong) study for a 7-year follow-up. PA was measured by the Physical Activity Scale of the Elderly (PASE). Cardiorespiratory fitness, expressed as maximal oxygen uptake (VO2max), was assessed by performing symptom-limited maximal exercise testing on an electrically braked bicycle ergometer and 6-m walk test. We aimed to examine the independent and combined effect of PA and VO2max with all-cause mortality by cox proportional hazards models. Ninety-nine deaths occurred over a mean follow-up of 5.3 ± 0.8 years. PA was inversely associated with all-cause mortality in unadjusted and fully-adjusted models, and the association was still significant after further adjusted for VO2max. In stratified analysis, PA was significantly related to all-cause mortality within both unfit and fit strata. As compared with those being active and fit, physically inactive and cardiorespiratory unfit individuals had the highest all-cause mortality risk. Physically active but unfit individuals and inactive but fit individuals had similar all-cause mortality risk. Among older adults, PA was an important predictor of all-cause mortality independently of VO2max. High cardiorespiratory fitness does not necessarily confer low mortality risk in physically inactive older adults.