Cardiopulmonary Exercise Testing Research Articles

Exercise oscillatory ventilation as a predictor of mortality in patients with amyloid cardiomyopathy

Abstract Background Exercise oscillatory ventilation (EOV) signals multiple abnormalities in hemodynamics and ventilatory control which may predict poor outcome in patients with cardiac diseases. Purpose To assess whether EOV (+) patients with amyloid cardiomyopathy show higher mortality rates compared to their counterparts without EOV. Methods We analyzed cardiopulmonary exercise testing results for EOV defined by continuous (>60% of exercise duration) oscillations in minute ventilation (VE), cycling with a frequency of one minute and an amplitude above 15% of resting VE, in patients with amyloid cardiomyopathy. Results 156 patients with amyloid cardiomyopathy, aged 78 (±7) years, 87% male with a NYHA functional class of II (49.4%) and median B-type natriuretic peptide levels of 2548 (1374-4703) ng/L. Comorbidities include hypertension (73.1%), polyneuropathy (45.5%), coronary heart disease (41.0%), diabetes mellitus (17.3%) and chronic obstructive pulmonary disease (10.9%). Patients had a mean peak oxygen consumption of 14.8 (±4.42) ml/kg·min and a VE to carbon dioxide production (VCO2) slope ≥ 40 in 67.9% of cases. EOV was seen in 38 (24.4%), clearly absent in 92 (59.0%) and not clearly differentiable in 26 (16.7%) patients. 33 (21.2%) had a HF-related hospitalization and 31 (19.9%) died. EOV shows a hazard ratio of 2.35 (CI 1.088 – 5.075, p-value <0.05) for all-cause mortality. In fact, the log-rank test showed a difference in survival time between patients with and without EOV (p=0.03) with a median survival time of 46 months. Conclusion EOV may improve the prognostic yield of incremental CPET in patients with amyloid cardiomyopathy.Kaplan-Meier Curve for EOV

Atrial and ventricular arrhythmias in young, lifelong and retired elite endurance athletes

Abstract Background Whilst endurance athletes are known to have an overall higher prevalence of atrial fibrillation (AF), the prevalence of other non-sustained and sustained atrial arrhythmias (AAs) and ventricular arrhythmias (VAs) remains poorly defined. Purpose We aimed to define the prevalence of non-sustained and sustained AAs (including AF) and VAs in a healthy cohort of young, lifelong and retired elite endurance athletes. We also sought to assess associations between arrhythmias, fitness and measures of cardiac structure. Methods Holter monitors in healthy endurance athletes (n=288) from an international cohort of elite endurance athletes (the Pro@Heart consortium) were analysed for the presence of sustained and non-sustained AAs and VAs. Athletes were sub-divided into young elite athletes (n=176) and former elite athletes (n=112) of which 60 were lifelong (≥2.5 hours/week) and 52 retired (<2.5 hours/week) athletes (determined by current high-intensity exercise activity). Each athlete underwent cardio-pulmonary exercise testing, echocardiography and contrast-enhanced cardiac MRI. Participants with known structural or electrical cardiac disease were excluded. Independent T-test / One-Way ANOVA (parametric data) or Mann-Whitney U / Kruskal-Wallis Tests (non-parametric data) assessed for differences between the groups. Results Young athletes (n=176, 70.5% male) were significantly fitter with a greater degree of cardiac remodelling as compared with lifelong (n=60, 63.3% male) and retired (n=52, 82.7% male) athletes (Figure 1). The prevalence of non-sustained AAs (young: 4.0% vs lifelong: 66.7% vs retired: 61.5%, p<0.001), sustained AAs (young: 0.6% vs lifelong: 8.3% vs retired: 15.4%, p<0.001) and non-sustained VAs (young: 1.7% vs lifelong: 18.3% vs retired: 23.1%, p<0.001) was higher in lifelong and retired athletes compared with young athletes (Figure 2). Non-sustained VAs were predominately monomorphic (85%), short and moderate rate (median duration 2.8 seconds and heart rate 154 beats per minute). No athletes developed sustained VAs and/or sudden cardiac arrest. Young athletes had less VAs that were multifocal in origin compared with lifelong and retired athletes (young: 29.5%, lifelong: 37.3%, retired: 53.5%, p=0.027). There was no difference in prevalence of any arrhythmia between lifelong and retired athletes. There were no significant correlations between arrhythmias and fitness or cardiac imaging parameters. Conclusion Healthy athletes have a significant prevalence of non-sustained atrial and ventricular arrhythmias and sustained atrial arrhythmias that is more prevalent in older athletes. In older athletes, the prevalence of arrhythmias is similar regardless of whether athletes are actively engaged in training or retired suggesting that pro-arrhythmic remodelling in athletes is sustained, not immediately reversible and may be minimally responsive to detraining.Arrhythmias and cardiac imagingArrhythmias amongst athlete groups

Enhanced diagnostic accuracy of cardiovascular magnetic resonance in identifying heart failure with preserved ejection fraction through assessment of right ventricular systolic dysfunction

Abstract Backgrounds Right ventricular maladaptive response to increased afterload affects exercise performance in heart failure with preserved ejection fraction (HFpEF). We investigated its role in the diagnosis of early stage of HFpEF with cardiac magnetic resonance (CMR) and invasive cardiopulmonary exercise testing (iCPET). Methods One hundred forty-five patients with suspected HFpEF were prospectively recruited from two centers and 113 of them completely underwent echocardiography, iCPET, and CMR. The diagnosis of HFpEF was based on the result of iCPET (pulmonary capillary wedge pressure > 15mmHg at resting and >25mmHg at peak exercise). Area under the curve (AUC) was determined by comparing HFpEF with non-HFpEF patients. Results Seventy-two HFpEF (68±10 years) and forty-one non-HFpEF (66±11 years) were identified. The resting pulmonary artery compliance was significantly reduced in HFpEF. CMR right ventricle longitudinal strain and left atrial reservoir strain had the highest diagnostic accuracy (AUCs 0.805 and 0.776, respectively). There is a sex disparity in the diagnosis accuracy of left atrial (LA) reservoir strain, with male patients exhibiting a significantly increased AUC (0.801) compared to females (AUC 0.559). Conclusions Right ventricular systolic dysfunction is an early indicator of HFpEF, accompanied by impaired LA filling. The diminished LA filling may be more prevalent in male patients, suggesting distinct early pathophysiological progressions between genders.

Exaggerated blood pressure response to submaximal exercise must be considered relative to fitness: strong associations with hypertensive target organ damage

Abstract Exaggerated systolic blood pressure (SBP) during submaximal exercise is associated with increased cardiovascular (CV) risk. However, findings are mixed and new evidence indicates that cardiorespiratory fitness should be considered for proper clinical interpretation of exercise SBP responses. This study aimed to determine the relationship between SBP response to submaximal effort corrected for fitness and abnormalities of cardiac structure and function. Methods Each of 231 participants (age 54±12 years; 53% females) with controlled clinic BP, no evidence for ischemic heart disease, valvular heart disease or heart failure underwent cardiopulmonary exercise testing (Bruce protocol), resting and exercise echocardiography and 24h ABPM. Submaximal exercise SBP (measured at the 2nd stage of Bruce protocol) was corrected for two fitness variables: 1) peak VO2 and 2) maximal workload in METs (SBP/peakVO2 and SBP/METs). Results There were no, or weak, associations with exercise SBP and target organ damage. However, there was a progressive deterioration of cardiac function and structure parameters across the exercise SBP tertiles corrected for fitness (Table 1). Both SBP/peakVO2 and SBP/METs significantly correlated with left ventricular (LV) mass, LV diastolic and systolic, and left atrial parameters (Table 2). ROC analysis revealed good performance of corrected SBP response to submaximal exercise in detection of LV hypertrophy and diastolic dysfunction (AUC 0.792 and 0.808, and 0.771 and 0.802 for SBP/peakVO2 and SBP/METs, respectively; Figure). Conclusions Fitness-corrected SBP responses to submaximal exercise can identify more profound target organ damage with respect to cardiac function and structure even among patients with controlled clinic BP. Exaggerated BP response to exercise must be considered relative to fitness for proper clinical interpretation of BP responses to exercise testing.Figure

Early detection of cardiac dysfunction using shear wave imaging: insights into reduced cardiorespiratory fitness in childhood cancer survivors

Abstract Background Diastolic dysfunction is thought to be the earliest cardiotoxic sequel after cancer therapy among childhood cancer survivors. Despite many survivors do exhibit reduced cardiorespiratory fitness (CRF) potentially due to cardiotoxicity, current echocardiographic parameters fail to detect hidden diastolic dysfunction early after therapy (1). High frame rate (HFR) shear wave imaging (SWI) is a novel tool that could give insights about myocardial stiffness, which is a key determining factor of diastolic function. Purpose We aimed at testing the ability of SWI to detect early alterations in myocardial stiffness among childhood cancer survivors and its relation with the reduced CRF. Methods Fifty childhood cancer survivors (mean 20 ±3 years) who received chemo-and/or- radiotherapy (mean time after treatment: 4 ±3 years) and thirty-two matched healthy volunteers (HV) were recruited. Conventional as well as HFR echocardiographic images (ca. 1200 frames/second) were acquired at rest using a modified commercial echocardiography machine. All participants underwent an incremental, symptom-limited cardiopulmonary exercise test on a treadmill measuring peak oxygen consumption (VO2 peak). HFR data were analysed offline. An anatomical M mode was drawn along the ventricular septum, and tissue Doppler acceleration maps were extracted to measure SW velocities after mitral valve closure (MVC) (Figure 1). Results Among cancer survivors, left ventricular ejection fraction (LVEF) and global longitudinal strain were significantly lower compared to HV (56 % ±4 vs 59 % ±4, and 17.6 % ±1.6 vs 19.1 % ±1.2, respectively; p <0.001). However, both LVEF and GLS were within the normal range and none of them correlated with the peak VO2 (Figure 2A&B). None of the echocardiographic diastolic parameters (e.g. mitral E, E/e’, left atrial volume or TR jet velocity) showed significant difference between both groups (P > 0.05). The mean SW velocities were significantly higher in cancer survivors compared to HV (3.9 ±0.6 m/s vs 3.2 ±0.3 m/s respectively; p <0.001). Interestingly, SW velocities among cancer survivors showed moderate significant negative correlation with the VO2 peak (r= -0.590, p <0.001) indicating increasing myocardial stiffness as the cardiorespiratory fitness declined (Figure 2C). Conclusions Our data indicate that myocardial stiffness in cancer survivors is significantly increased. We hypothesize that this increased stiffness may at least in part explain the significantly reduced cardiorespiratory fitness in this population. Echocardiographic shear wave elastography appears as a promising non-invasive tool for early detection of diastolic dysfunction in follow-up of childhood cancer survivors.Figure 1.Figure 2.

Interventricular abnormal septum displacement as contributory mechanism for impaired peak oxygen consumption and exercise cardiac output response in heart failure

Abstract Background In Heart failure (HF), the role of septum position and abnormal right ventricular (RV) geometry in determining exercise performance is unknown. Especially an abnormal interventricular septal (IVS) position is a well-known sign of RV pressure overload which affects left ventricular filling and output due to interdependence. Aim We postulated that an abnormal septum displacement during exercise and RV geometry alteration would affect peak exercise oxygen consumption (VO2) and cardiac output (CO) increase. Methods 17 HF patients with reduced ejection fraction (HFrEF) (mean age 71±12) underwent a cardiopulmonary exercise testing imaging (iCPET) with RV 3D-imaging analysis and were compared with a control population (mean age 67±14). 3D imaging of the RV chamber was examined off-line using the 4D RV TomTec software and obtained 3D mesh of the RV model using custom software to obtain the mean curvature value of IVS in 4 regions of: inflow tract (RVIT), outflow tract (RVOT), apical and body.We acquired measurements of curvature during end-diastole (ED) and at end systole (ES) phases and obtained a parametric curvature map. Results HF patients typically exhibited an abnormal of septal curve, with a more leftward configuration either at rest and under exercise (rest =−0.01±0.004 at ED, and −0.01±0.006 at ES; peak exercise= −0.01±0.004 at ED, and −0.01±0.004 at ES, Figure) compared to controls (rest=−0.02±0.003 at ED, and −0.02±0.005 at ES; peak exercise −0.02±0.008 at ED, and −0.03±0.006 at ES, Figure). Notably, the degree of the IVS curvature was found to linearly correlate with an impaired gas exchange performance as lower peak VO2 and a limited CO in HF (respectively r=0.62, p<0.001 and r=0.5, p<0.001 at ED during exercise; r=0.34, p<0.001 at ES during exercise, Figure). Conclusions In HF, the RV geometrical alterations reflected by an abnormal IVS displacement appear as novel contributory factors to a reduced exercise performance, impaired oxygen uptake and decreased CO.

Cardiorespiratory fitness and working memory in persons with traumatic brain injury: a cross-sectional analysis

ABSTRACT Introduction Cognitive impairment is a highly impactful consequence of traumatic brain injury (TBI) and there are limited evidence-based treatment practices to combat these impairments. Evidence from other populations suggest that aerobic exercise training (AET) is beneficial for a variety of cognitive deficits, but the research in persons with TBI to date is equivocal. One potential reason is the heterogeneity of exercise prescriptions and outcome measures. This stems from the fact that studies have not been designed based on previous data supporting a specific AET prescription to target a cognitive domain. The primary purpose of this cross-sectional analysis was to examine the relationship between cardiorespiratory fitness (CRF), as a cross-sectional surrogate of AET, and cognition in persons with TBI to inform future research. Methods Cross-sectional analysis was conducted on baseline data of persons with TBI who completed neuropsychological assessments to evaluate several cognitive domains and a cardiopulmonary exercise test (CPET) to measure CRF. Based on the normal distribution of an outcome, Pearson’s r or Spearman’s ρ was calculated to measure the relationship between CRF and cognition. Results Data were analyzed for all participants who demonstrated valid CPETs (n = 21 of 29). Based on the cycle ergometer-based norms of CRF, males in this sample were in the 69th percentile and females in this sample were in the 56th percentile, with high variability across individuals. Higher CRF, as measured by peak power output (Wpeak), was significantly associated with greater working memory (ρ = 0.465, p = 0.017), even after post-hoc corrections. Conclusions These data suggest average and highly variable CRF in persons with TBI of all severity and support cycle ergometry-based CPET testing in this population. Further, these data provide support for future research applying AET to target working memory and possibly other executive functions in persons with TBI. This research is a small step toward large-scale randomized controlled trials that can directly impact clinical care to treat cognitive symptoms post-TBI.

Efficacy of balloon pulmonary angioplasty in patients with chronic thromboembolic pulmonary disease and exercise pulmonary hypertension

BackgroundThe efficacy of balloon pulmonary angioplasty (BPA) in patients with chronic thromboembolic disease (CTEPD) without pulmonary hypertension (PH) remains unknown. Exercise PH (Ex-PH) is associated with impaired exercise capacity, even when pulmonary hemodynamics are normal at rest. We hypothesized that patients with Ex-PH could be the candidates for BPA. This study aimed to determine the prevalence and clinical profiles of Ex-PH and the effect of BPA on oxygenation and Ex-PH in patients with CTEPD and mean pulmonary arterial pressure (mPAP) ≤ 20 mmHg. MethodsWe retrospectively reviewed 23 patients (median age 65 years) with CTEPD and mPAP ≤20 mmHg at rest who underwent cardiopulmonary exercise testing with right heart catheterization. Patients were divided into two groups: Ex-PH, defined by an mPAP/cardiac output (CO) slope (mPAP/CO slope) > 3.0, and non-Ex-PH. ResultsOverall, 12 and 11 patients were identified as Ex-PH and non-Ex-PH groups, respectively. There were no significant differences in clinical parameters, including hemodynamics at rest, and blood gas analysis between Ex-PH and non-Ex-PH groups. Among 9 patients with Ex-PH, BPA improved World Health Organization-functional class and PaO2 at rest and was associated with a decrease in the mPAP/CO slope. All 3 patients discontinued LTOT after BPA. There were no significant complications during each BPA session. ConclusionsEx-PH was common among patients with CTEPD without PH. BPA could improve symptoms, oxygenation, and exercising hemodynamics in patients with CTEPD and Ex-PH.

Comparison of exercise training modalities and change in peak oxygen consumption in heart failure with preserved ejection fraction: a secondary analysis of the OptimEx-Clin trial.

Exercise training (ET) is an effective therapy in heart failure with preserved ejection fraction (HFpEF), but the influence of different ET characteristics is unclear. We aimed to evaluate the associations between ET frequency, duration, intensity [% heart rate reserve (%HRR)] and estimated energy expenditure (EEE) with the change in peak oxygen consumption (V̇O2) over 3 months of moderate continuous training (MCT, 5×/week) or high-intensity interval training (HIIT, 3×/week) in HFpEF. ET duration and heart rate (HR) were recorded with a smartphone application. EEE was calculated using the HR data during ET and the individual HR-V̇O2 relationships during cardiopulmonary exercise testing. Differences between groups and associations between ET characteristics and peak V̇O2 change were assessed with linear regression analyses. Peak V̇O2 improved by 9.2 ± 13.2% after MCT and 8.7 ± 15.9% after HIIT (P = 0.67). The average EEE of 1 HIIT session was equivalent to ∼1.42 MCT sessions and when adjusted for EEE, the mean difference between MCT and HIIT was -0.1% (P = 0.98). For both MCT and HIIT, peak V̇O2 change was positively associated with ET frequency (MCT: R2 = 0.103; HIIT: R2 = 0.149) and duration/week (MCT: R2 = 0.120; HIIT: R2 = 0.125; all P < 0.05). Average %HRR was negatively associated with peak V̇O2 change in MCT (R2 = 0.101; P = 0.034), whereas no significant association was found in HIIT (P = 0.234). Multiple regression analyses explained ∼1/3 of the variance in peak V̇O2 change. In HFpEF, isocaloric HIIT and MCT seem to be equally effective over 3 months. Within each mode, increasing ET frequency or duration/week may be more effective to improve peak V̇O2 than increasing ET intensity.

The Impact of Interactive Video Games Training on the Quality of Life of Children Treated for Leukemia

Objectives: The study aimed to assess the impact of interactive video games (IVGs) as a form of physical activity (PA) on the quality of life. Methods: The study used a quality-of-life questionnaire (KIDSCREEN-10) and the HBSC questionnaire. In order to determine individual IVGs training parameters, an initial assessment of cardiorespiratory fitness level was performed, using the Cardio Pulmonary Exercise Test—Godfrey’s progressive protocol. Children in the intervention group participated in 12 interval training sessions using IVGs (Microsoft’s Xbox 360 S console with Kinect,). Results: The study included 21 patients (7–13 years old; 12 boys and 9 girls) treated for acute lymphoblastic leukemia (n = 13) and acute myeloid leukemia (n = 8). Before the IVGs, all children had insufficient PA levels (90% of children in the intervention group and 90.91% of children in the control group did not engage in any PA during the last 7 days). After the intervention, 80% of the children in the IVGs group undertook PA lasting at least 60 min a day, three times a week. They exhibited better well-being, a subjective feeling of improved physical fitness (p &lt; 0.0001), a greater subjective sense of strength and energy (p &lt; 0.0001), and less feeling of sadness (p = 0.0016) than the children from the control group (p = 0.0205). Conclusions: The results of our study confirmed that an attractive form of virtual game or sport is willingly undertaken by children undergoing cancer treatment, and has significant benefits in improving the quality-of-life parameters. There is a clear need to create specific recommendations and rehabilitation models for children with cancer.

Maximum heart rate prediction equations based on field-tests with adequate clinical applicability for aerobic exercise prescription to individuals after stroke

Objectives 1) to develop two maximum heart rate (HRmax) prediction equations for individuals after stroke; 2) to investigate its validity. Methods The HRmax was obtained by a Cardiopulmonary Exercise Test (CPET). Participants also completed the Six-minute Walking Test (6MWT) and the Incremental Shuttle Walking Test (ISWT). Results 60 individuals (54(12) years; 64(69) months after stroke) were included. Twenty individuals (58(10) years; 67(61) months after stroke) were included in the cross-validation group. For the first model, the following equation was generated (equation-1): HRmax= 87.655 + 0.726 (HRpeak in the 6MWT) − 0.386 (age in years), (R2=0.53; Standard Error of the Estimate (SEE)= 15.35; p < 0.0001). For the second model, the following equation was generated (equation-2): HRmax= 96.523 + 0.681 (HRpeak in the ISWT) − 0.039 (walking distance in meters in the ISWT) − 0.400 (age in years), (R2=0.53; SEE = 15.51; p < 0.0001). Significant and high magnitude agreement was found between the HRmax obtained by the CPET and the predicted HRmax by equation-1 (ICC= 0.85; 95% CI= 0.63 − 0.94) and equation-2 (ICC= 0.72; 95% CI= 0.29 − 0.89). Conclusions Two HRmax prediction equations have been developed and showed adequate validity. Professionals will have the option of choosing one of the two equations to use.

Improvements in Cardiopulmonary Exercise Test Results in Atrial Fibrillation Patients After Radiofrequency Ablation in Kazakhstan

This prospective study evaluates the impact of radiofrequency ablation (RFA) on cardiorespiratory indicators in patients with long-standing persistent atrial fibrillation admitted to the Heart Center UMC between January 2022 and April 2024 in Astana, Kazakhstan. The study aims to assess the functional cardiac benefits of RFA. Out of 717 registered atrial fibrillation patients, 104 were examined before and 3 months after ablation, focusing on cardiorespiratory parameters. A before-and-after analysis using linear mixed models was applied to evaluate changes in cardiorespiratory parameters post-RFA. Significant improvements were noted across various measures. VO2 max increased from 11.5 ± 4.4 mL/kg/min to 18.0 ± 4.5 mL/kg/min (p &lt; 0.001). Oxygen uptake improved from 7.2 ± 2.6 mL/beat to 11.0 ± 3.4 mL/beat (p &lt; 0.001). The 6-min walking test distance rose from 306 ± 82 m to 400 ± 48 m (p &lt; 0.001). METs increased from 4.4 ± 1.6 to 8.0 ± 1.3 (p &lt; 0.001). Heart rate at peak exercise decreased from 175.5 ± 18.6 to 147.2 ± 12.3 beats per minute (p &lt; 0.001). NT-proBNP levels decreased from 1357 ± 1182 to 415 ± 339 pg/mL (p &lt; 0.001). Patients with persistent atrial fibrillation undergoing RFA showed functional improvements in CPET indicators such as VO2 max, METs, O2 pulse, heart rate, and the 6-min walking test. Improvements were also seen in Nt-proBNP analysis. These results emphasize the need for longitudinal follow-up to optimize outcomes and minimize medical risks.

Aerobic capacity of healthy young men associated with muscle oxygen extraction rate of the vastus lateralis muscle.

The determinants of aerobic capacity are oxygen delivery by the cardiopulmonary system and oxygen extraction by the skeletal muscles. However, the impact of the oxygen extraction capacity of the skeletal muscle is unclear. This study aimed to examine the associations between aerobic capacity; muscle strength, endurance, mass, and quality; and oxygen extraction capacity. Twenty-seven healthy young men (mean age, 20.7 ± 0.8 years; body mass index, 21.6 ± 3.2 kg m-2) were recruited. The following parameters were determined: peak work rate (WR) and oxygen uptake (V˙O2) corrected for body mass using the cardiopulmonary exercise testing; muscle strength and endurance using isokinetic muscle testing; muscle mass using bioelectrical impedance; muscle quality (muscle echo intensity) using an ultrasound imaging device, and muscle oxygen extraction rate (MOER) using near-infrared spectroscopy. Multiple regression analysis was performed using WR/kg peak and V˙O2/kg peak as dependent variables and each assessment index as an independent variable. Multiple regression analysis with WR/kg peak as the dependent variable resulted in the adoption of SMI (β = -0.41, P = 0.036), muscle echo intensity (β=-0.45, P = 0.012) and ΔMOER (β = 0.73, P < 0.001) as significantly associated factors. Multiple regression analysis with V˙O2/kg peak as the dependent variable resulted in ΔMOER (β = 0.65, P = 0.001) being adopted as a significantly associated factor. These findings suggest that muscle oxygen extraction rate is associated with aerobic capacity. MOER is a useful indicator because it is not affected by body mass.

Criterion Validity of Screening Tools and Field-Based Tests for Health-Related Physical Fitness in Inflammatory Bowel Disease.

Monitoring health-related physical fitness (HRPF) may benefit proactive Inflammatory Bowel Disease (IBD) management. However, knowledge regarding HRPF in patients with IBD is limited and gold standard tests are impractical for widespread use, necessitating simpler methods. This study evaluated the criterion validity of screening tools and field-based tests compared to gold standard tests for HRPF in patients with IBD. Adult patients with IBD completed screening tools, field-based tests, and gold standard tests for HRPF. Criterion validity was examined through (intraclass) correlation coefficients and Bland-Altman plots. Predictive capacity of the screening tools was examined with receiver operating curve analysis. Among 53 included patients, screening tools demonstrated poor-to-moderate validity compared to the cardiopulmonary exercise test (CPET) for cardiorespiratory fitness. Very strong correlations were found for four-site skinfold thickness and multi-frequency bioimpedance analysis (BIA) with deuterium oxide dilution for body fat percentage (ICC = 0.90, ICC = 0.93), and between the steep ramp test and CPET (r = 0.95) for cardiorespiratory fitness. The steep ramp test also correlated strongly with isokinetic quadriceps (r > 0.75) and hamstring (r > 0.74) strength. Hand-held dynamometry and the sit-to-stand test showed strong correlations with hamstring strength (r > 0.80, r > 0.76). Negligible correlations were found for field-based tests compared to isokinetic quadriceps and hamstring endurance. Four-site skinfold thickness and BIA showed good agreement with the gold standard for body fat measurement. The steep ramp test demonstrated strong correlations with the gold standard tests for cardiorespiratory fitness and quadriceps and hamstring strength, while hand-held dynamometry and the sit-to-stand test showed strong correlations with hamstring strength.

Determinants of Longitudinal Changes in Exercise Capacity in Patients with Independent Functioning on Hemodialysis.

Patients with chronic kidney disease reportedly have decreased muscle oxygen utilization, which most substantially decreases exercise capacity, followed by cardiac reserve. However, determinants of longitudinal changes in exercise capacity in patients on hemodialysis and the effects of long-term exercise interventions are unknown. This study was conducted to clarify these concerns. This was a prospective cohort study. Patients on hemodialysis that were not hospitalized were followed from baseline up to 2years, and cardiopulmonary exercise testing results, including peak oxygen uptake, peak work rate, heart rate reserve, and ventilatory equivalent for carbon dioxide slope, as well as implementation of exercise interventions were assessed. Based on the 2-year change in peak oxygen uptake, they were divided into improvement or declined groups. Forty-five patients who were not hospitalized completed the follow-up were analyzed. In the improvement group, the variation was determined by an increase in peak work rate, which is a peripheral factor (partial regression coefficient 0.08 [95% CI = 0.01 to 0.16]), while in the decline group, the variation was determined by a decrease in the ventilatory equivalent for carbon dioxide slope, which is a cardiac factor (partial regression coefficient = -0.12; 95% CI = -0.21 to -0.03). Moreover, exercise intervention was associated with the change in peak oxygen uptake (partial regression coefficient = 3.09; 95% CI = 1.45 to 4.72). Exercise intolerance even in patients on hemodialysis that were not hospitalized and stable progressed over time with deterioration of cardiac reserve, whereas exercise interventions were associated with improved exercise capacity through enhanced peripheral function. The results support the early measurement of cardiopulmonary or skeletal muscle reserve through cardiopulmonary exercise testing and the implementation of long-term exercise interventions based on the measurement results to address the potential deterioration in exercise capacity associated with reduced cardiac reserve, even in patients on hemodialysis that are asymptomatic and stable.

Improved functional oral intake and exercise training attenuate decline in aerobic capacity following chemoradiotherapy in patients with esophageal cancer.

To investigate the impact of chemoradiotherapy on the physical fitness of patients with oesophageal cancer, and the clinical factors influencing it. A total of 67 participants successfully completed the study, with 18 of them engaging in supervised, in-hospital aerobic training at moderate intensity for a minimum of 20 sessions. Cardiopulmonary exercise testing, hand grip strength, body composition assessed via bioelectrical impedance analysis, patient-generated subjective global assessment, albumin, and the Functional Oral Intake Scale (FOIS) were evaluated before chemoradiotherapy and 6-8 weeks after its completion. Among the participants, cardiopulmonary fitness, hand grip strength, and phase angle of BC-BIA declined during chemoradiotherapy. Before and after chemoradiotherapy, V̇O2peak was 19.6 ± 4.4 and 17.4 ± 3.9 mL/min/kg respectively. The improvement in FOIS during chemoradiotherapy showed a positive correlation with changes in aerobic capacity. Additionally, exercise training was associated with attenuating the decline in aerobic capacity. Physical fitness deteriorated in patients with oesophageal cancer following chemoradiotherapy. Improvement in dysphagia helps maintain aerobic capacity. Additionally, exercise training has the potential to mitigate the decline. This discovery can serve as a reference for enhancing holistic care for patients with oesophageal cancer.

Cardiac Comorbidity and Exercise Intolerance in Bilateral Lung Transplant Recipients Followed at a Pediatric Center.

Reduced exercise capacity is common in young bilateral lung transplantation (Bi-LTx) recipients, but longer-term data on cardiac comorbidities are limited. We evaluate potential cardiac contributions to long-term exercise intolerance in this population. All Bi-LTx recipients at a single pediatric center, who completed routine clinical post-transplant cardiac assessment, including echocardiogram, cardiac exam, and cardiopulmonary exercise testing (CPET), were included. Cardiac risk factors (CRFs) were assessed by history and laboratory tests. CPET-derived peak and percent-predicted peak myocardial oxygen consumption (VO2 peak, ppVO2 peak) were used to quantitate exercise capacity. Percent-predicted peak oxygen pulse (pp peak O2 pulse) assessed stroke volume. 15 patients (67% M; median age 21.6years, median follow-up from Bi-LTx 7.0years) were included. Almost all patients (14, 93%) had multiple CRFs; hypertension and hyperlipidemia/dyslipidemia were the most common. On CPET, 93% (n = 14) had abnormal (≤ 85%) ppVO2 peak (median 59%). 73% (n = 11) had abnormal pp peak O2 pulse (median 74%). Ten had blunted heart rate response to exercise. Nine had left ventricular diastolic dysfunction (LV-DD) on echocardiogram. Median percent-predicted forced expiratory volume in one second was 70%. One had severe chronic lung allograft dysfunction. Cardiac risk factors and exercise intolerance are common among young Bi-LTx recipients years post-transplant, even among those without significant pulmonary dysfunction. High prevalence of multiple CRFs, LV-DD, chronotropic dysfunction, and abnormal stroke volume suggest cardiac comorbidities may contribute to intolerance. Medical management of CRFs and tailored exercise may decrease cardiac risk and improve functional capacity for Bi-LTx survivors.

Prognostic Value of Repeated Peak Oxygen Uptake Measurements in LVAD Patients

BackgroundPeak oxygen uptake (pVO2) predicts mortality in heart failure patients on left ventricular assist device (LVAD) support. This follow-up of the PRO-VAD study examines the prognostic value of repeated pVO2 measurements during long-term follow-up. MethodsThis multicenter follow-up study included patients from the original PRO-VAD cohort who performed a cardiopulmonary exercise test (CPET) twice. Patients were categorized into four groups based on pVO2 levels at the two CPETs: Low at both tests, Low at the first and High at the second test, High at the first and Low at the second test, and High at both tests. Low pVO2 was defined as ≤14 mL/kg/min (or ≤12 mL/kg/min if beta-blocker tolerant), while values above these thresholds were considered High. Survival outcomes were analyzed using the Kaplan-Meier method and cause-specific Cox analysis. ResultsThe study included 152 patients with repeated CPETs at approximately 6 and 12 months following LVAD implantation. The cohort showed slight but significant pVO2 improvement (median change: 0.4 mL/kg/min, P = 0.04). Persistently High pVO2 (76 patients) was associated with a fivefold reduction in mortality hazard (HR 0.20, P = 0.002), compared to persistently Low pVO2 (46 patients). Improvement from Low to High pVO2 (21 patients) displayed similar benefits (HR 0.21, P = 0.02). ConclusionpVO2 measurements remain predictive of mortality upon reiteration in LVAD patients, with changes in pVO2 providing additional prognostic value in identifying patients with an excellent outcome on ongoing LVAD support and in identifying patients requiring further interventions.

Association Between Coronary Microvascular Dysfunction and Exercise Capacity in Dilated Cardiomyopathy.

Aerobic exercise capacity is an independent predictor of mortality in dilated cardiomyopathy (DCM), but the central mechanisms contributing to exercise intolerance in DCM are unknown. Characterize coronary microvascular function in DCM and determine if cardiovascular magnetic resonance (CMR) measures are associated with aerobic exercise capacity. Prospective case-control comparison of adults with DCM and matched controls. Adenosine-stress perfusion CMR to assess cardiac structure, function and automated inline myocardial blood flow quantification, and cardiopulmonary exercise testing (CPET) to determine peak VO2, were performed. Pre-specified multivariable linear regression, including key clinical and cardiac variables, was undertaken to identify independent associations with peak VO2. Sixty-six patients with DCM (mean age 61 years, 71% male) were propensity-matched to 66 controls (mean age 59 years, 71% male) based on age, sex, body mass index and diabetes. DCM patients had markedly lower peak VO2 (19.8±5.5 versus 25.2±7.3mL/kg/min; P<0.001). The DCM group had greater left ventricular (LV) volumes, lower systolic function, and had more fibrosis compared to controls. In the DCM group, there was similar rest but lower stress myocardial blood flow (1.53±0.49 versus 2.01±0.60mL/g/min; P<0.001) and lower MPR (2.69±0.84 versus 3.15±0.84; P=0.002). Multivariable linear regression demonstrated that LV ejection fraction, extracellular volume fraction and MPR, were independently associated with percentage predicted peak VO2 in DCM (R2=0.531, P<0.001). In comparison to controls, DCM patients have lower stress myocardial blood flow and MPR. In DCM, MPR, LV ejection fraction and fibrosis are independently associated with aerobic exercise capacity.

Effect of Sarcobesity Index and Body Adipose Tissue Variables on Cardiopulmonary Exercise Testing Performance in Colorectal Surgery Setting: A Retrospective Cohort Study.

Aims/Background The prognostic significance of body composition variables has become a popular area of research over the recent years. This study aimed to determine whether adipose tissue variables and sarcobesity index measured by computed tomography (CT) could predict cardiopulmonary exercise testing (CPET) performance and long-term mortality in patients undergoing major colorectal surgery. Methods The Strengthening the Reporting of Cohort Studies in Surgery (STROCSS) statement standards were followed to conduct a retrospective cohort study of consecutive patients who had CPET prior to major colorectal surgery between January 2011 and January 2017. Receiver Operating Characteristic curve analysis was conducted to assess the discriminative performances of adipose tissue variables. The association between CT-derived adipose tissue variables (sarcobesity index, visceral adipose tissue, subcutaneous adipose tissue, and total adipose tissue) and CPET performance and mortality were assessed using regression analyses. Results 457 patients were included. Total adipose tissue evaluated via 2-dimensional (2D) and 3-dimensional (3D) approaches predicted oxygen uptake (V̇O2) Rest, V̇O2 anaerobic threshold (AT), ventilatory equivalents for carbon dioxide (V̇E/V̇CO2) AT, ventilatory equivalents for oxygen (V̇E/V̇O2) AT, V̇O2 peak, exercise time, maximum work, peak metabolic equivalents (METS), peak respiratory rate (RER), and peak oxygen pulse. Sarcobesity index (2D and 3D) predicted V̇O2 Rest, V̇O2 AT, V̇E/V̇CO2 AT, V̇O2 peak, maximum work, peak METS, maximum heart rate, and peak RER. Neither total adipose tissue nor sarcobesity index (2D and 3D) predicted 1-year, 3-year, or 5-year mortality. There was no difference in the discriminative performance of adipose tissue variables in predicting mortality. Conclusion The CPET performance may be predicted by radiologically measured adipose tissue variables and sarcobesity index. However, the prognostic value of the variables may not be significant in this setting.