Regulation of whole-transcriptome sequencing expression in COPD after personalized precise exercise training: a pilot study.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is one of the world's leading causes of death and a major chronic respiratory disease. Aerobic exercise, the cornerstone of pulmonary rehabilitation, improves prognosis of COPD patients; however, few studies have comprehensively examined the changes in RNA transcript levels and the crosstalk between various transcripts in this context. This study identified the expression of RNA transcripts in COPD patients who engaged in aerobic exercise training for 12 weeks, and further constructions of the possible RNAs networks were made. METHODS: Peripheral blood samples for all four COPD patients who benefited from 12 weeks of PR were collected pre- and post-aerobic exercises and evaluated for the expression of mRNA, miRNA, lncRNA, and circRNA with high-throughput RNA sequencing followed by GEO date validation. In addition, enrichment analyses were conducted on different expressed mRNAs. LncRNA-mRNA and circRNA-mRNA coexpression networks, as well as lncRNA-miRNA-mRNA and circRNA-miRNA-mRNA competing expression networks (ceRNAs) in COPD were constructed. RESULTS: We identified and analyzed the differentially expressed mRNAs and noncoding RNAs in the peripheral blood of COPD patients' post-exercise. Eighty-six mRNAs, 570 lncRNAs, 8 miRNAs, and 2087 circRNAs were differentially expressed. Direct function enrichment analysis and Gene Set Variation Analysis showed that differentially expressed RNAs(DE-RNAs) correlated with several critical biological processes such as chemotaxis, DNA replication, anti-infection humoral response, oxidative phosphorylation, and immunometabolism, which might affect the progression of COPD. Some DE-RNAs were validated by Geo databases and RT-PCR, and the results were highly correlated with RNA sequencing. We constructed ceRNA networks of DE-RNAs in COPD. CONCLUSIONS: The systematic understanding of the impact of aerobic exercise on COPD was achieved using transcriptomic profiling. This research offers a number of potential candidates for clarifying the regulatory mechanisms that exercise has on COPD, which could ultimately help in understanding the pathophysiology of COPD.

Oxygen uptake is more efficient in idiopathic pulmonary arterial hypertension than in chronic thromboembolic pulmonary hypertension.

BACKGROUND AND OBJECTIVE: The responses of oxygen uptake efficiency (OUE) during cardiopulmonary exercise training (CPET) have not been reported in patients with pulmonary hypertension. We aimed to investigate the differences in OUE between patients with idiopathic pulmonary arterial hypertension (IPAH) and chronic thromboembolic pulmonary hypertension (CTEPH). METHODS: Forty-four patients with IPAH and 29 patients with CTEPH were retrospectively enrolled into our study. All patients underwent right-heart catheterization, pulmonary function test and performed the 6-min walk test and CPET. RESULTS: We found that oxygen uptake efficiency plateau (OUEP) and oxygen uptake efficiency at anaerobic threshold (OUE@AT) was significantly higher in IPAH than that in CTEPH (both P = 0.002). However, patients with CTEPH had lower mean pulmonary artery pressure, pulmonary vascular resistance and transpulmonary gradient (all P < 0.05). The correlation between OUEP and heart rate at anaerobic threshold (HR_AT) was significant (r = 0.376, P < 0.05); however, no statistically significant correlation was found with ventilation at anaerobic threshold (VE_AT) (r = -0.074, P > 0.05) in patients with IPAH. In patients with CTEPH, both anaerobic threshold (r = 0.307, P > 0.05) and VE_AT (r = -0.709, P < 0.0001) were reduced. OUEP were higher in WHO functional class I/II patients than in WHO functional class III/IV patients (all P < 0.05). CONCLUSIONS: OUEP and OUE@AT are higher in IPAH than that in CTEPH not in proportion to haemodynamics, probably due to differences in cardiac function and pulmonary vascular occlusion. OUEP correlates well with the exercise capacity and the severity of the disease.

Chronic bronchitis leads to accelerated hyperinflation in COPD patients during exercise.

BACKGROUND AND OBJECTIVE: It is not known whether patients with chronic obstructive pulmonary disease (COPD) have a different exercise capacity with (CB(+) ) or without accompanying chronic bronchitis (CB(-) ). METHODS: We conducted spirometry, a 6-min walk distance test and cardiopulmonary exercise test in 50 age-matched healthy control subjects, 45 COPD patients without CB (CB(-) ) and 37 COPD patients with CB (CB(+) ). A multiple regression model was established to identify factors independently associated with peak oxygen consumption ( V ˙ O 2 ). RESULTS: Patients with and without CB had similar forced expiratory volume in 1 s (FEV1 ). CB(+) patients had a lower V ˙ O 2 . CB(+) and CB(-) participants had similar increases in tidal volume at peak exercise; however, CB(+) patients had an increased respiratory rate (RR). These patients reached the peak value for ratio of end-expiratory lung volume to total lung capacity (TLC) at a lower work load. A stepwise multiple linear regression analysis identified chronic bronchitis, FEV1 , diffusing capacity for carbon monoxide, the ratio of residual volume to TLC and serum tumour necrosis factor-α as independent predictors of peak V ˙ O 2 . CONCLUSIONS: CB significantly lowers exercise capacity in COPD patients because of dynamic hyperinflation during exercise. The accelerated dynamic hyperinflation may contribute to increased airway and systemic inflammation in COPD patients.

Rehabilitation practice patterns for patients with heart failure: the Asian perspective.

More countries around world have begun to use cardiac rehabilitation in patients diagnosed with chronic heart failure (HF). Asia is the largest continent in the world and, depending on its economy, culture, and beliefs, a given Asian country differs from Western countries as well as others in Asia. The cardiac rehabilitation practice patterns for patients with HF are somewhat different in Asia. In addition to the formal pattern of Western practice, it also includes special techniques and skills, such as Taiji, Qigong, and Yoga. This article describes cardiac rehabilitation patterns for patients with HF in most Asian countries and areas.

[Peak oxygen consumption, NT-proBNP and echocardiographic changes in patients with chronic heart failure].

OBJECTIVE: To assess peak oxygen consumption (peak VO2) derived from cardiopulmonary exercise testing (CPET), concentrations of NT-proBNP and echocardiographic changes in patients with chronic heart failure (CHF) and reduced left ventricular ejection fraction (LVEF, <40%). METHODS: Seventy patients were included and divided into two groups according to the New York Heart Association (NYHA) classification: NYHA II group (17 cases) and NYHA III-IV group (53 cases). The basic clinical information, plasma concentration of NT-proBNP at rest, echocardiographic parameters and peak VO2from CPET were compared between two groups. Correlation among peak VO2, NT-proBNP and echocardiographic parameters in this patient cohort was assessed and their abilities to discriminate the NYHA III-IV grade were analyzed through c-Statistic. RESULTS: Left atrial diameter ((51.3 ± 7.2) mm vs. (44.0±7.4) mm, P<0.001) was larger, plasma concentration of NT-proBNP (1 379-4 399 pmol/L vs. 1 109-2 356 pmol/L, P<0.01) was higher and peak VO2((13.4 ± 3.5) ml·kg⁻¹·min⁻¹ vs. (18.2 ± 3.7) ml·kg⁻¹·min⁻¹, P<0.001) were significantly lower in NYHA III-IV group than those in NYHA II group. However, left ventricular end-diastolic diameter (LVEDD) and LVEF were similar between two groups. Peak VO2correlated significantly with NT-proBNP (r=-0.311, P<0.01), but neither peak VO2nor NT-proBNP correlated with echocardiographic parameters (LA, LVEDD and LVEF). ROC analysis showed that peak VO2had the strongest discriminatory power for detecting NYHA III-IV grade patients (AUC=0.835, P<0.001), followed by the NT-proBNP (AUC=0.723, P<0.01). CONCLUSION: Peak VO2is a more sensitive parameter to detect the disease aggravation (NYHA III-IV grade) of the CHF patients with reduced LVEF compared to plasma NT-proBNP and echocardiographic parameters (LA, LVEDD, LVEF).

[Clinical value of cardiopulmonary exercise testing derived oxygen uptake efficiency parameters in patients with end-stage chronic heart failure].

OBJECTIVE: To assess the cardiopulmonary exercise testing (CPET) derived performance of oxygen uptake and ventilation efficiency parameters, including oxygen uptake efficiency plateau (OUEP) , oxygen uptake efficiency slope (OUES), V·E/V·CO2 slope and lowest V·E/V·CO2, in patients with end-stage chronic heart failure (CHF) and evaluate their clinical value on monitoring cardiac function and hemodynamic status. METHODS: A total of 26 end-stage CHF patients considered for heart transplantation were enrolled in this study. CPET, echocardiography and invasive hemodynamic examinations with Swan-Ganz flowing balloon catheter were performed. Correlation analysis was made between oxygen uptake and ventilation efficiency parameters from CPET and echocardiographic and hemodynamic parameters. RESULTS: OUEP and OUES showed good correlation with peak oxygen consumption (peak V·O2) (r = 0.535, P < 0.01;r = 0.840, P < 0.001). In end-stage CHF patients, the slope of OUEP with respect to peak V·O2 is about 32, but the slope of OUES with respect to peak V·O2 is only about 2. The difference was 16 times. The change of OUEP was more sensitive and significant than those of OUES and peak V·O2 (P < 0.05). OUEP, peak V·O2 (%pred), V·E/V·CO2 slope and lowest V·E/V·CO2 were all correlated well with non-invasive hemodynamic parameters peak cardiac output (r = 0.535, P < 0.01; r = 0.652, P < 0.001; r = -0.640, P < 0.001; r = -0.606, P = 0.001 respectively) and peak cardiac index (r = 0.556, P < 0.01;r = 0.772, P < 0.001; r = -0.641, P < 0.001; r = -0.620, P < 0.001 respectively) derived from CPET, but not correlated with invasive hemodynamic parameters cardiac output and cardiac index at rest (P > 0.05). Both peak V·O2 (%pred) and V·E/V·CO2 slope were significantly correlated with invasive hemodynamic parameters systolic pulmonary arterial pressure (r = -0.424, P < 0.05; r = 0.509, P < 0.01) and mean pulmonary arterial pressure (r = -0.479, P < 0.05; r = 0.405, P < 0.05). Peak V·O2 (%pred) was also significantly correlated with pulmonary capillary wedge pressure (r = -0.415, P < 0.05), and V·E/V·CO2 slope was significantly correlated with pulmonary vascular resistance (r = 0.429, P < 0.05). CONCLUSIONS: The oxygen uptake and ventilation efficiency parameters derived from CPET, including peak V·O2, OUEP, lowest V·E/V·CO2 and V·E/V·CO2 slope etc, are objectively monitoring and evaluating cardiac function and hemodynamic status. And they are useful for optimizing clinical management of patients with end-stage CHF.

[Correlation between VE/VCO2slope and echocardiographic derived systolic pulmonary artery pressure in patients with chronic heart failure].

OBJECTIVE: To explore the relationship between ventilator efficiency of cardiopulmonary exercising test (the slope of the relation between ventilation and carbon dioxide production, VE/VCO(2)slope) and systolic pulmonary artery pressure (sPAP) measured by echocardiography in patients with chronic heart failure (HF). METHODS: Data from 86 HF patients who were treated in Fuwai Hospital between December 2012 and July 2014 and performed the symptom limited maximal cardiopulmonary exercise test (CPET) and echocardiography were retrospectively analyzed.H F patients were divided into 3 groups (mild, moderate and severe) according to the maximum oxygenconsumption (peakVO(2)). RESULTS: There is a significant linear correlation between VE/VCO(2)slope and sPAP (r=0.260, P=0.016). Using VE/VCO(2)slope>34.2 as a cutoff value to predict patients with sPAP>50 mmHg (1 mmHg=0.133 kPa) yielded a sensitivity of 70.0% and a specificity of 64.3%. The degree of the linear correlation between VE/VCO(2)slope and sPAP is stronger in mild HF patients (peakVO(2)>14 ml·kg(-1)·min(-1), r=0.686, P<0.001). Using VE/VCO(2) slope>34.2 as a cutoff value to predict sPAP>50 mmHg in mild HF patients, the sensitivity is 71.4% and the specificity is 93.8%. CONCLUSION: There is a significant linear correlation between VE/VCO(2)slope and sPAP in HF patients. VE/VCO(2)slope>34.2 is linked with a high possibility of sPAP>50 mmHg in HF patients, especially for patients with mild HF. Invasive hemodynamic examination and impact of special therapy are warranted in future studies to veryfy present results.

[Parameters of oxygen uptake and carbon dioxide output ventilatory efficiency during exercise are index of circulatory function in normal subjects].

OBJECTIVE: To observe oxygen uptake efficiency plateau (OUEP, i.e.highest V˙O2/V˙E) and carbon dioxide output efficiency (lowest V˙E/V˙CO2) parameter changes during exercise in normal subjects. METHODS: Five healthy volunteers performed the symptom limited maximal cardiopulmonary exercise test (CPET) at Harbor-UCLA Medical Center. V˙O2/V˙E and V˙E/V˙CO2 were determined by both arterial and central venous catheters. After blood gas analysis of arterial and venous sampling at the last 30 seconds of every exercise stage and every minute of incremental loading, the continuous parameter changes of hemodynamics, pulmonary ventilation were monitored and oxygen uptake ventilatory efficiency (V˙O2/V˙E and V˙E/V˙CO2) was calculated. RESULTS: During CPET, as the loading gradually increased, cardiac output, heart rate, mixed venous oxygen saturation, arteriovenous oxygen difference, minute ventilation, minute alveolar ventilation, tidal volume, alveolar ventilation and pulmonary ventilation perfusion ratio increased near-linearly (P < 0.05-0.01, vs.resting); arterial oxygen concentration maintained at a high level without significant change (P > 0.05); stroke volume, respiratory rate, arterial partial pressure of carbon dioxide, arterial blood hydrogen ion concentration and dead space ventilation ratio significantly changed none-linearly (compare resting state P < 0.05-0.01).OUE during exercise increased from 30.9 ± 3.3 at resting state to the highest plateau 46.0 ± 4.7 (P < 0.05 vs.resting state), then, declined gradually after anaerobic threshold (P < 0.05-0.01, vs.OUEP) and reached 36.6 ± 4.4 at peak exercise. The V˙E/V˙CO2 during exercise decreased from the resting state (39.2 ± 6.5) to the minimum value (24.2 ± 2.4) after AT for a few minutes (P > 0.05 vs.earlier stage), then gradually increased after the ventilatory compensation point (P < 0.05 vs.earlier stage) and reached to 25.9 ± 2.7 at peak exercise. CONCLUSIONS: Cardiac and lung function as well as metabolism change during CPET is synchronous.In the absence of pulmonary limit, appearing before and after anaerobic threshold, OUEP and lowest V˙E/V˙CO2 could be used as reliable parameters representing the circulatory function.

[Association of oxygen uptake efficiency in exercise test with exercise capacity in patients with stable chronic obstructive pulmonary disease].

OBJECTIVE: To explore the characteristics of oxygen uptake efficiency (OUE) in patients with chronic obstructive pulmonary disease (COPD), and to analyze the relationship between OUE and the exercise capacity. METHODS: Pulmonary function test and cardiopulmonary exercise test were performed in 59 patients with stable COPD (grade I, n = 15; grade II, n = 16; grade III, n = 19; grade IV, n = 9) and 29 healthy volunteers of the same age. Their successive breathing respiratory exchange parameters were collected and analyzed. t test and χ(2) test were used for 2 sample comparison, while multiple comparisons among groups were performed by using single factor analysis of variance. Correlation analysis was done by Pearson correlation test. RESULTS: Compared with the normal control group [(2.2 ± 0.4) L·min(-1)·lg(L·min(-1))(-1); (35 ± 4) ml/L], the OUES and OUEP of the COPD patient group [(1.9 ± 0.3) L·min(-1)·lg(L·min(-1))(-1); (31 ± 5) ml/L]were significantly lower (t = 4.57, 3.39, all P < 0.01) . The OUE of the grade I patients showed no significant difference compared with the normal control group (t = 0.36-1.49, all P > 0.05), while the OUES of the grade II-IV patients [(2.05 ± 0.26), (1.76 ± 0.28) and (1.63 ± 0.19) L·min(-1)·lg(L·min(-1))(-1)] decreased significantly compared to the normal control group [(2.23 ± 0.39) L·min(-1)·lg(L·min(-1))(-1); t = 2.42-5.26, all P < 0.05]. The OUEP and the OUE at the anaerobic threshold of the grade II-III patients [(31 ± 4) and (31 ± 5), (29 ± 5) and (29 ± 5) ml/L] decreased significantly compared to the normal control group [(35 ± 4) and (34 ± 4) ml/L, t = 2.18-4.83, all P < 0.05]. The OUES, OUEP and the OUE at the anaerobic threshold in COPD patients were correlated (r = 0.500-0.625, all P < 0.01) positively with the exercise tolerance (peak VO2% pred). CONCLUSIONS: The oxygen uptake efficiency of patients with COPD is significantly reduced compared to that of the normal subjects, and is correlated positively with the exercise capacity.

Oxygen uptake efficiency plateau: physiology and reference values.

The relationship of oxygen uptake [Formula: see text] to ventilation [Formula: see text], i.e., oxygen uptake efficiency (OUE) is known to differ between normal subjects and patients with congestive heart failure. However, only the oxygen uptake efficiency slope (OUES, i.e., slope of [Formula: see text] has previously been reported. To understand the physiology and to improve the usefulness of OUE in assessing cardiovascular function, we analyzed the complete response pattern of OUE during entire incremental exercise tests and ascertained effect of age, body size, gender, fitness, and ergometer type on exercise OUE to generate reference values in normal healthy subjects. We investigated the effect of age, gender, and fitness on OUE using incremental cardiopulmonary exercise in 474 healthy subjects, age 17-78 years, of which 57 were highly fit. The final methods of OUE analysis were: (1) OUE plateau at the highest values (OUEP), (2) OUE at anaerobic threshold (OUE@AT), and (3) OUES using the entire exercise period. The OUEP and OUE@AT were similar, highly reproducible, less variable than the OUES (p < 0.0001), and unaffected by the study sites or types of ergometry. The resultant prediction equations from 417 normal subjects for men were OUEP (mL/L) = 42.18 - 0.189 × years + 0.036 × cm and OUES [L/min/log(L/min)] = -0.610 - 0.032 × years + 0.023 × cm + 0.008 × kg. For women, OUEP (mL/L) = 39.16 - 0.189 × years + 0.036 × cm and OUES [L/min/log(L/min)] = -1.178 - 0.032 × years + 0.023 × cm + 0.008 × kg. OUE@AT was similar to OUEP. Extreme fitness has a minimal effect on OUEP. OUEP is advantageous, since it measures maximal oxygen extraction from ventilated air but does not require high intensity exercise. The OUEP is a non-invasive parameter dependent only on age, gender, height, and cardiovascular health.

Impact of Exercise Training at Different Intensity Levels on Cardiac Function and Exercise Capacity in Patients with Chronic Heart Failure: A Prospective Cohort Study.

OBJECTIVE: To investigate training at different intensity levels on cardiac function, exercise capacity, and health-related quality of life in patients with chronic heart failure. METHODS: This prospective cohort study enrolled patients with chronic heart failure at Beijing Rehabilitation Hospital, Beijing, China from January 2018 to January 2020. Participants received conventional therapy (non-exercise group) or therapy plus cycle ergometer exercises at an intensity of 80% anaerobic threshold (EA group) and Δ50% power above anaerobic threshold (EB group) for 12 weeks. The primary outcome was peak oxygen uptake. RESULTS: Forty-five patients (15/group) completed the study without serious complications. Exercise training at an intensity of Δ50% power above anaerobic threshold had better effects on exercise capacity than exercise at an intensity of 80% anaerobic threshold, as shown by a greater improvement in peak oxygen uptake (20.3 ± 4.1 vs 16.8 ± 3.2 mL/min/kg), peak O2 pulse (12.5 ± 2.3 vs 10.1 ± 2.1 mL/beat), and peak workload (123.1 ± 26.9 vs 102.8 ± 29.5 W) in patients with chronic heart failure (all p < 0.001). Exercise improved the 6-min walk test distance (control: 394.0 ± 74.1; EA: 481.4 ± 89.4; EB: 508.9 ± 92.5 m; p < 0.001) and health-related quality of life (control: 40.7 ± 12.3; EA: 16.2 ± 8.6; EB: 11.5 ± 6.4; p < 0.001). CONCLUSION: Compared with an intensity of 80% anaerobic threshold, exercise training at an intensity of Δ 50% power above anaerobic threshold was safe and had better effects on cardiac function, exercise capacity, and health-related quality of life.

[Using changes of left cardiac functional parameters and CPET evaluated the clinical effectiveness of individualized precise exercise overall program management of chronic disease I --Analysis between groups].

Objective: To explore and study the clinical usefulness of continuous dynamic recording of left cardiac function changes forevaluation the improvement in patients with chronic disease after 3 months of intensive control of individualized precision exercise overall manage program. Methods: From 2018 to 2021, 21 patients with chronic cardiovascular and cerebrovascular metabolic diseases mainly controlled by our team were selected to complete the cardiopulmonary exercise test (CPET) and Non-invasive synchronous cardiac function detector (N-ISCFD), electrocardiogram, radial pulse wave, jugular pulse wave and cardiogram data were continuously recorded for 50s.According to the titration results under CPET and continuous functional parameters monitoring, a holistic plan with individualized moderate exercise intensity as the core was developed for 3 months of intensive management, and then N-ISCFD data collection was repeatedafter signing the informed consent. All N-ISCFD data were analyzed in the 50s according to the optimal report mode of Fuwai Hospital and 52 cardiac functional indexes were calculated. The data before and after the enhanced control were compared and the paired T-test was used to statistically analyze the changes of groups. Results: Twenty-one patients with chronic diseases (16 male and 5 female) were (54.05±12.77,29~75) years, BMI (25.53±4.04,16.62~31.7) kg/m2.Comparison with baseline,the whole group analysis: ①The body weight, BMI, systolic blood pressure and diastolic blood pressure of patients were significantly decreased(P＜0.01).②CPET Peak VO2 was (64.93±24.22, 26.96~103.48) %Pred before enhanced control, and (85.22±30.31, 43.95~140.48) %Pred after enhanced control, and increased (35.09±27.87, 0.12~129.35) % after enhanced control compared with before enhanced control. The AT, Peak VO2/HR, Peak Work Rate, OUEP, FVC, FEV1, FEV3/FVC% and MVV were significantly increased (P＜0.01) and the Lowest VE/VCO2 and VE/VCO2 Slope were significantly decreased(P＜0.01).③Core indicators of left heart function:Ejection fraction was significantly increased from (0.60±0.12,0.40~0.88) to(0.66±0.09, 0.53~0.87)(P＜ 0.01), by (12.39±14.90,-12.32~41.11)%. The total peripheral resistance was significantly decreased from (1579.52±425.45,779.46~2409.61) G/(cm4·s),to(1340.44±261.49,756.05~1827.01) G/(cm4·s)(P＜0.01), by (12.00±17.27,37.79~28.61) %.The left stroke index, cardiac total power, ejective pressure and left ventricular end diastolic volumewere significantly improved (P＜0.05).The change analysis of each indicator for each patient is shown in the individualized analysis section of this study. Conclusion: Use CPET and continuous functional monitoring we can safely and effectively develop the overall program of individualized exercise in patients with chronic diseases. Long-term intensive management and control can safely and effectively significantly improve the cardiovascular function of patients. Continuous dynamic recording of changes in left and right cardiac functional parameters can be a simple way to supplement CPET to evaluate cardiovascular function.

[Clinical study on the diagnostic value of cardiopulmonary exercise test for coronary atherosclerotic heart disease].

Objective: To evaluate the value of cardiopulmonary exercise testing in diagnosing coronary atherosclerotic heart disease（CHD). Methods: A total of 156 patients with suspected CHD（The patient's condition is relatively stable, aged 18 to 80 years）were performed for cardiopulmonary exercise testing, ECG exercise test and coronary angiography. Based on the results of coronary angiography, the sensitivity, specificity and diagnostic value of relevant indicators of cardiopulmonary exercise testing (CPET) parameters (Peak VO2%pred、Peak O2 pulse%pred、ΔVO2/ΔWR) in diagnosing CHD were analyzed by statistical methods based on the results of coronary angiography. Results: Useing the best cut-off point of Peak VO2 ≤69%pred for detecting CHD, the sensitivity was 55.1%, the specificity was 77.0%, and the AUC was 0.698. The sensitivity, specificity and AUC of peak O2 pulse%pred were 50.7%, 72.4% and 0.58 respectively. ΔVO2/ΔWR sensitivity in diagnosing CHD was 44.9%, specificity was 87.4%, AUC was 0.647. The sensitivity of peak O2 pulse%pred and ΔVO2/ΔWR were much higher than the ECG exercise test, the difference was statistically significant (P<0.01). Conclusion: The sensitivity of some indexes of CPET in diagnosing CHD was better than ECG exercise test, the specificity and diagnostic value of the optimal cut-off point are high. CPET has predictive value for the diagnosis of CHD, it can diagnose CHD early and accurately.

[Relationship of characteristic duration and magnitude of the oscillatory breathing related with exercise functional capacity in patients with chronic heart failure].

Objective: To find out the relationship between the duration and amplitude of oscillatory breathing (OB) and their exercise capacity in patients with chronic heart failure (CHF) we did this study. Methods: Two hundred and thirty-seven CHF patients performed a maximum incremental upright cycle ergometry cardiopulmonary exercise testing (CPET). Respiratory gas exchange was measured on a breath-by-breath basis throughout the test. OB was defined as 3 or more continuous cycle fluctuations of ventilation during CPET, and the amplitude of VE oscillations exceed 25% of concurrent mean value. The CHF patients with OB (OB+) were divided into 3 sub-groups according to their Peak VO2. Group1 (mild OB+) Peak VO2 of ≥16 ml/min/kg, group 2 (moderate OB+) Peak VO2 is between 12~16 ml/min/kg, group 3 (severe OB+) Peak VO2 ≤ 12 ml/(min·kg). Results: There were 78(32.6%) patients detected as OB+ in 237 CHF patients. Among OB+ patients, OB duration in s related negatively to Peak VO2 in mL/min/kg (r=-0.82), Peak VO2 in %pred (r=-0.65), VO2 at AT (r=-0.78), and related positively to VE/VCO2 at AT (r=0.61). Conclusion: OB duration is related negatively to exercise capacity of CHF patients.

[Cardiopulmonary exercise testing was used to evaluate objectively and quantitatively the holistic function in patients after neoadjuvant chemotherapy].

Objective: Cardiopulmonary exercise testing(CPET)was used to evaluate objectively and quantitatively the holistic function in patients accepted preoperative chemotherapy. Methods: This study investigated reliable objective and quantitative assessment methods of symptom limited maximal incremental CPET before and after chemotherapy in patients with 6 esophageal cancer. We re-analyzed the changes in cardiopulmonary, metabolism, and other functions physiologic parameters of CPET. Results: After patients accepted preoperative chemotherapy,Peak oxygen consumption (Peak VO2)(P<0.05), anaerobic threshold (AT) and peak oxygen pulse (Peak O2 paulse), oxygen uptake efficiency plateau (OUEP)were decreased (P<0.01). The lowest of ventilatory equivalent for carbon dioxide and slope of ventilatory equivalent for carbon dioxide were increased (P<0.05). For individual of all patients, except one patient's Peak VO2 and OUEP slightly increased,all of the above indicators were reduced in the remaining patients. The lowest of ventilatory equivalent for carbon dioxide and slope of ventilatory equivalent for carbon dioxide increased in all the patients,except one patient's slope of ventilatory equivalent for carbon dioxide decreased slightly. The heart rate of 6 patients showed an upward trend in each state, but there was no statistical difference. Three of the 6 patients had blood pressure measurement, and the other 3 patients had a significant decrease in diastolic blood pressure (P<0.05) except at extreme state.The patients had lower oxygen uptake at AT(P<0. 01) and extreme state (P<0. 05) than that before chemotherapy. The oxygen uptake efficiency in a warm-up state(P<0. 01),and an AT state(P<0. 05)after chemotherapy were lower than those before chemotherapy. The ventilator equivalent for carbon dioxide after chemotherapy was in the each states presented an upward trend, but only ventilator equivalent for carbon dioxide after in the warm-up state (P<0.05) and AT(P<0.01) had statistical significance. oxygen pulse in all four states showed a decreasing trend, and only at AT (P<0.05) showed a significant decrease.After chemotherapy,the PETCO2 in a warm-up state after chemotherapy was lower than that before chemotherapy(P<0. 05); the PETO2 in a quiescent state,a warm - up state,and an extreme state after chemotherapy were higher than those before chemotherapy;but there was nosignificant difference. Conclusion: The holistic functional capacity of patients with esophageal significantly decreased after 136 days chemotherapy. The circulatory functionalandentilator functional parameters significantly decreased after chemotherapy.

[Cardiopulmonary exercise test accurately prognoses risk of postoperative complications in patients undergoing lung resection in good functional status].

Objective: To explore the value of predicting accurately the risk of complications after thoracoscopic lung resection by preoperative CPET index. Methods: Selected 448 patients who completed CPET with static pulmonary function test (PFT) before operation, followed up to discharge after operation, and were divided into groups according to the presence or absence of complications: 418 cases had no complications and 30 cases had complications (including 1 death). Calculate peak oxygen uptake (Peak VO2) and other core indicators, compare the similarities and differences between patients with and without complications, and calculate the best cut value and odds ratio (OR). Results: ①In this study, there were 184 males and 264 females, aged (54±12) (16~79) years old, 85 cases with smoking, 23 cases with lymph node metastasis, 68 cases with hypertension, 45 cases with diabetes. Peak VO2 and Peak WR are respectively (93.31±17.73)(44~158)%pred and (99.70±22.93)(53~179)%pred. FVC, VC and FEV1/FVC are respectively (99.46±15.60)(42~150)%pred, (101.58±15.77)(44~148) %pred and (98.36±9.27)(52~134) %pred. 2There are significant differences(P<0.01) in gender, age, smoking history, lymph node metastasis and core indicators of Peak VO2 (%pred), Peak WR (%pred), FVC, VC, Rest SBP and Peak SBP . There are also differences(P<0.05) in Peak VO2 (ml/(min·kg)), Peak VO2/HR (%pred), VE/VCO2 slope, VE/ VCO2@AT, Peak HR (bmp), RER, FEV1 and fasting blood glucose. No difference in other indicators. ③OR are respectively 4.24 and 3.72 (P<0.01) when the cutting points are Rest SBP(140 mmHg) and FEV1(80%pred). While the OR of Peak VO2(80%pred)、Peak SBP(180 mmHg)、Peak VO2 (20 ml/(min·kg)) and VE/VCO2 Slope(30) are respectively2.66、2.62、2.43 and 2.12 (P<0.05). Conclusion: For patients undergoing thoracoscopic lung resection with good function, the preoperative CPET core indicators can accurately predict the risk of postoperative complications, which is worthy of in-depth study.

[Primary clinical investigation of cardiopulmonary exercise gas exchange in pulmonary hypertension patients with and without right-to-left shunt].

Objective: The aim of this study is to determine the changes of gas exchange parameters during ramp incremental cardiopulmonary exercise test (CPET) in patients with pulmonary hypertension (PH) could identify the right to left shunt (R-L Shunt). Methods: We did a retrospective analysis of exercise gas exchange parameters for 73 PH patients and 14 normal subjects as control, in Fuwai Hospital from October 2016 to August 2017, who did CPET with signature on content form. The gas exchange data of CPET were double-blindly independently interpreted by four export-doctors. According to the reading results of CPET, the PH patients were divided into four groups: ① R-L shunt positive group, ② R-L shunt suspicious group, ③R-L shunt negative group, ④late open R-L Shunt positive group. Results: Minute ventilation (VE), ventilatory equivalents for carbon dioxide and oxygen (VE/VCO2, VE/VO2), end-tidal partial pressure of oxygen (PETO2)in R-L shunt positive group were significantly increased ((7.36 ± 2.72) L/min, (1.84± 3.59), (5.02 ±4.34), (3.75±2.64) mmHg) at the beginning of exercise, and were also significantly higher than the control ((4.26 ± 2.59) L/min, (2.22± 2.08), (1.46 ±4.68), (3.96 ± 2.82) mmHg); Partial pressure of carbon dioxide in end expiratory gas (PETCO2) was decreased (-1.63 ±1.66) mmHg, and was significantly lower than control (2.22 ± 2.08) mmHg (P<0.01). Respiratory quotient (RER), carbon dioxide, VE/VCO2, VE/VO2, PETO2 in late open R-L Shunt positive group were suddenly increased ((0.40 ± 0.08), (11.07 ± 5.60),(30.55 ±7.89), (13.72 ±2.21) mmHg) at the end of exercise near the peak, significantly higher than control too ((0.38± 0.12), (5.67± 4.60), (4.54 ± 3.83), (5.51± 4.24) mmHg); PETCO2 was suddenly decreased at the end of the exercise compared to the resting stage (-6.82 ± 1.96) mmHg, and was significantly different from the control (5.67 ±4.60) mmHg. Carbon dioxide ventilatory efficiency, oxygen uptake ventilatory efficiency relative to the peak power (-8.38 ±3.24, -13.14 ± 6.47) at the recovery stage in late open R-L shunt positive group are significantly lower than control (6.22 ±2.87, 16.56± 4.20) (P<0.01). Conclusion: Cardiopulmonary function and ventilation efficiency of patients withpulmonary hypertension are significantly decreased; pulmonary hypertension and right to left shunt in patients not only resting ventilation efficiency is limited more serious; The characteristics of R-L shunt are the sudden increase of PETO2, VE/ VCO2, VE, RER and sudden decrease of PETCO2 and VO2/ VE at the beginning of exercise, and commonly companied with decreased SpO2. For the delay open R-L shunt, these changes occurred near the peak exercise rather than the beginning, and these characteristic changes quickly reversed after stopping exercise.

[The impacts of outpatient vs inpatient holistic management based on exercise training on cardiac rehabilitation efficacy among patients with chronic heart failure].

Objective: To evaluate the impacts of outpatient vs inpatient exercise training (ET) on cardiac rehabilitation efficacy among patients with chronic heart failure (CHF). Methods: Thirty six patients who were diagnosed with CHF in Beijing Rehabilitation Hospital from September 2015 to September 2018, were randomly divided into three groups: control group (n=12), outpatient ET group (n=12) and inpatient ET group (n=12). Patients in control group were treated with conventional cardiac rehabilitation without ET, patients in outpatient and inpatient ET groups were treated with holistic cardiac rehabilitation with the core of ET according to individualized exercise prescription based on cardiopulmonary exercise testing (CPET). Exercise intensity of cycle ergometer was Δ50% power above anaerobic threshold (AT), 30 min/d, 5 d/week, for 12 weeks. General information, CPET parameters, echocardiogram, 6 minute walking distance (6MWD) and quality of life (QoL) score of three groups of patients before and after treatment were recorded. Results: All patients in 3 groups finished symptom-limited CPET and patients in ET groups finished 12 weeks - ET safely without complications. Before treatment, there were no significant differences in CPET parameters, echocardiogram results, 6MWD and QoL score among 3 groups (P>0.05). After treatment, AT (ml/min, ml/(min·kg), %pred), peak oxygen uptake (VO2) (ml/min, ml/(min·kg), %pred), peak oxygen pulse(ml/beat), peak workload(W/min, %pred), left ventricular ejection fraction (LVEF) and 6MWD of patients in outpatient and inpatient ET groups were significantly higher than those of patients in control group (P<0.05), QoL score of patients in outpatient and inpatient ET groups was lower than that of patients in control group(P<0.05). To be noted, there were no obvious differences in CPET indexes, echocardiogram results, 6MWD and QoL score in patients between outpatient ET group and inpatient ET group (P>0.05). For patients in control group, there were no significant differences in above parameters before and after treatment (P>0.05). AT(ml/min, ml/(min·kg)), Peak VO2 (ml/min, ml/(min·kg), %pred), peak oxygen pulse(ml/beat, %pred), peak workload(W/min, %pred), LVEF and 6MWD of patients in outpatient and inpatient ET groups were significantly higher than those before treatment (P<0.05), QoL score of patients in outpatient and inpatient ET groups after treatment was significantly lower than that before treatment (P<0.05). Conclusion: Outpatient ET can improve the cardiopulmonary function, exercise tolerance and QoL of CHF patients, which has no significant difference compared with inpatient ET, indicating that outpatient cardiac rehabilitation, as an effective rehabilitation mode, is deserved to be applied widely.

[Effect of different work rate increasing rate on the overall function evaluation of cardiopulmonary exercise testing I-peak parameters and changes in respiratory exchange rate].

Objective: To observe the effect of healthy volunteers different work rate increasing rate cardiopulmonary exercise test (CPET) on the peak exercise core indicators and the changes of respiratory exchange rate (RER) during exercise, to explore the effect of different work rate increasing rate on CPET peak exercise related indicators. Methods: Twelve healthy volunteers were randomly assigned to a moderate (30 W/min), a relatively low (10 W/min) and relatively high (60 W/min) three different work rate increasing rate CPET on different working days in a week. The main peak exercise core indicators of CPET data: VO2, VCO2, work rate (WR), breathe frequency(Bf), tidal volume (VT), ventilation (VE), heart rate (HR), blood pressure (BP), Oxygen pulse(O2P), exercise time and RER for each period of CPET were analyzed using standard methods. The ANOVA test and paired two-two comparison was performed on the difference of each index in the three groups of different work rate increasing rate. Results: Compared with the moderate work rate group, the peak work rate of the lower and higher work rate groups were relatively lower and higher, respectively ((162.04±41.59) W/min vs (132.92±34.55) W/min vs (197.42±46.14) W/min, P<0.01); exercise time was significantly prolonged and shortened ((5.69 ± 1.33) min vs (13.49 ± 3.43) min vs (3.56 ± 0.76) min, P<0.01); peak RER (1.27 ± 0.07 vs 1.18 ± 0.06 vs 1.33 ± 0.08, P<0.01~P<0.05) and the recovery RER maximum (1.72±0.16 vs 1.61±0.11 vs 1.81±0.14, P<0.01~P<0.05) were significantly decreased and increased. Conclusion: Different work rate increasing rate of CPET significantly change the Peak Work Rate, exercise time, Peak RER, and maximum RER during recovery. The CPET operator should choose an individualized work rate increasing rate that is appropriate for the subject, and also does not use a fixed RER value as a basis for ensuring safety, the subject's extreme exercise, and early termination of exercise.

[Effect of different work rate increasing rate on the overall function evaluation of cardiopulmonary exercise testing II- sub-peak parameters].

Objective: To observe the effect of healthy volunteers different work rate increasing rate cardiopulmonary exercise testing (CPET) on the sub-peak parameters . Methods: Twelve healthy volunteers were randomly assigned to a moderate (30 W/min), a relatively low (10 W/min) and relatively high (60 W/min) three different work rate increasing rate CPET on different working days in a week. The core indicators related to CPET sub-peak exercise of 12 volunteers were compared according to standard Methods: anaerobic threshold (AT), oxygen uptake per unit power (ΔVO2/ΔWR), oxygen uptake eficiency plateau,（OUEP), the lowest average of 90 s of carbon dioxide ventilation equivalent (Lowest VE/ VCO2), the slope of carbon dioxide ventilation equivalent (VE/ VCO2 Slope) and intercept and anaerobic threshold oxygen uptake ventilation efficiency value (VO2/ VE@AT) and the anaerobic threshold carbon dioxide ventilation equivalent value (VE/ VCO2@AT). Paired t test was performed on the difference of each parameter in the three groups of different work rate increasing rate. Results: Compared with the relatively low and relatively high work rate increasing rate group, the moderate work rate increasing rate group uptake eficiency plateau, (42.22±4.76 vs 39.54±3.30 vs 39.29±4.29) and the lowest average of 90 s of carbon dioxide ventilation equivalent (24.13±2.88 vs 25.60±2.08 vs 26.06±3.05) was significantly better, and the difference was statistically significant (P<0.05); Compared with the moderate work rate increasing rate group, the oxygen uptake per unit work rate of the relatively low and relatively high work rate increasing rate group increased and decreased significantly ((8.45±0.66 vs 10.04±0.58 vs 7.16±0.60) ml/(min·kg)), difference of which was statistically significant (P<0.05); the anaerobic threshold did not change significantly ((0.87±0.19 vs 0.87±0.19 vs 0.89±0.19) L/min), the difference was not statistically significant (P>0.05). Conclusion: Relatively low and relatively high power increase rate can significantly change the CPET sub-peak sports related indicators such as the effectiveness of oxygen uptake ventilation, the effectiveness of carbon dioxide exhaust ventilation, and the oxygen uptake per unit work rate. Compared with the moderate work rate increasing rate CPET, the lower and higher work rate increasing rate significantly reduces the effectiveness of oxygen uptake ventilation and the effectiveness of carbon dioxide exhaust ventilation in healthy individuals. The standardized operation of CPET requires the selection of a work rate increasing rate suitable for the subject, so that the CPET sub-peak related indicators can best reflect the true functional state of the subject.