Interpretation Of Cardiopulmonary Exercise Testing Research Articles

Comparison of Cardiorespiratory Fitness Prediction Equations and Generation of New Predictive Model for Patients with Obesity.

Cardiorespiratory fitness (CRF) is a critical marker of overall health and a key predictor of morbidity and mortality, but the existing prediction equations for CRF are primarily derived from general populations and may not be suitable for patients with obesity. Predicted CRF from different non-exercise prediction equations was compared with measured CRF of patients with obesity who underwent maximal cardiopulmonary exercise testing (CPET). Multiple linear regression was used to develop a population-specific nonexercise CRF prediction model for treadmill exercise including age, sex, weight, height, and physical activity level as determinants. Six hundred sixty patients underwent CPET during the study period. Within the entire cohort, R2 values had a range of 0.24 to 0.46. Predicted CRF was statistically different from measured CRF for 19 of the 21 included equations. Only 50% of patients were correctly classified into the measured CRF categories according to predicted CRF. A multiple model for CRF prediction (mL·min -1 ) was generated ( R2 = 0.78) and validated using two cross-validation methods. Most used equations provide inaccurate estimates of CRF in patients with obesity, particularly in cases of severe obesity and low CRF. Therefore, a new prediction equation was developed and validated specifically for patients with obesity, offering a more precise tool for clinical CPET interpretation and risk stratification in this population.

Integrative interpretation of cardiopulmonary exercise tests for cardiovascular risk stratification: a machine learning approach

Abstract Background and objectives Cardiopulmonary exercise testing (CPET) remains underutilized for cardiovascular (CV) risk assessment. Integrative interpretation of CPET results may improve characterization of cardiorespiratory fitness and assessment of CV risk. Therefore, we explored the clinical value of CPET-based phenomapping for CV risk stratification. Methods We retrospectively retrieved clinical data from 2280 patients with diverse CV risk (47.9% female) who underwent maximal CPET by cycle ergometry. We derived 18 key CPET indices as well as data on fatal and non-fatal CV events (median follow-up time: 5.3 years). Next, an unsupervised clustering algorithm (Gaussian Mixture modelling) subdivided the cohort in sex-specific phenogroups solely based on differences in CPET metrics. Clinical characteristics were compared across CPET phenogroups and their multivariable-adjusted association with future CV events was determined. Results 8 of the 18 CPET metrics were excluded from clustering due to high collinearity (i.e. an absolute Pearson correlation coefficient >0.8). Based on the remaining 10 CPET variables, the clustering algorithm subdivided the cohort in four male and four female CPET phenogroups. In both males and females, the phenogroups differed significantly in age, BMI, spirometric and CPET measurements and prevalence of hypertension, intake of antihypertensive and lipid-lowering drugs, CV disease and CV surgery (P<0.05 for trends). During follow-up, 278 males and 109 females experienced a CV event (43.9 and 16.2 events per 1000 years of follow-up, respectively). Compared to male phenogroup 1, male phenogroups 3 and 4 presented higher risk for incident CV events (multivariable-adjusted hazard ratio: 1.97 and 1.62; P≤0.027). Significant differences in risk for future CV events between the female phenogroups disappeared after adjustment for confounders. Conclusion Integrative CPET-based phenogrouping adequately stratified patients according to their risk for future CV events. Such phenomapping may facilitate comprehensive evaluation of CPET results and steer future CV risk management.Study flow and findings

Cardiopulmonary exercise testing in repaired tetralogy of Fallot and supraventricular arrythmias

Abstract Background The arrhythmia burden in adult patients (Ps) with tetralogy of Fallot (TOF) is considerable, being a major late complication in repaired TOF. The incidence of atrial arrhythmias is relatively high and one of the main causes of morbidity. Our aim was to assess which cardiopulmonary exercise testing (CPET) parameters best correlate with supraventricular arrythmias (SVA) to potentially improve identification of high-risk Ps. Methods A single-center retrospective analysis was performed from 2009 to 2018 on adult Ps with repaired TOF who underwent maximal CPET. Ambulatory ECG monitoring was used to analyze the arrhythmic profile. Demographics, standard measures of CPET interpretation, and major cardiovascular outcomes were collected. Multivariate analysis for the prediction of SVA was performed using Cox Regression, by including all statistically significant variables in the univariate analysis and those considered clinically relevant. Results CPET was performed in 63 repaired TOF Ps (57% male, mean age of 34 ± 9 years), with a mean follow-up of 60 ± 33 months. 56% Ps had severe pulmonary regurgitation and 48% Ps underwent pulmonary valve replacement (PVR). Supraventricular arrhythmias occurred in 12 Ps (19%), mainly atrial fibrillation or atrial flutter (67%). There were no statistically significant differences regarding the clinical profile and baseline CPET parameters between both groups, namely: age (p=0.113), male gender proportion (p=0.581), proportion of Ps who underwent PVR (p=0.578), RV systolic dysfunction prevalence (p=0.854) and peak oxygen uptake (p=0.083). VE/VCO2 slope was an independent predictor of SVA (HR 1.41, CI 95% 1.08-1.84, p=0.012). Exercise capacity assessed by estimated metabolic equivalents (METS), as well as the peak heart rate (PHR) during exercise (HR 0.86, CI 95% 0.76-0.96, p=0.007), revealed a protective effect regarding SVA (HR 0.71, CI 95% 0.51-0.98, p=0.045). Neither peak oxygen uptake (p=0.090) nor cardiorespiratory optimal point (p=0.427) showed statistically significant correlation with SVA during follow-up. Ps with a PHR above 165 bpm had a significantly higher survival free of SVA (log-rank p=0.045). Conclusion In our population, VE/VCO2 slope was an independent predictor of SVA during follow-up, while both a higher PHR and a higher exercise capacity had a protective effect. CPET could be an accessible way of improving risk-stratification of TOP Ps and should therefore be included in their routine assessment.

Using Machine Learning-Based Algorithms to Identify and Quantify Exercise Limitations in Clinical Practice: Are We There Yet?

Well-trained staff is needed to interpret cardiopulmonary exercise tests (CPET). We aimed to examine the accuracy of machine learning-based algorithms to classify exercise limitations and their severity in clinical practice compared with expert consensus using patients presenting at a pulmonary clinic. This study included 200 historical CPET data sets (48.5% female) of patients older than 40 yr referred for CPET because of unexplained dyspnea, preoperative examination, and evaluation of therapy progress. Data sets were independently rated by experts according to the severity of pulmonary-vascular, mechanical-ventilatory, cardiocirculatory, and muscular limitations using a visual analog scale. Decision trees and random forests analyses were calculated. Mean deviations between experts in the respective limitation categories ranged from 1.0 to 1.1 points (SD, 1.2) before consensus. Random forests identified parameters of particular importance for detecting specific constraints. Central parameters were nadir ventilatory efficiency for CO 2 , ventilatory efficiency slope for CO 2 (pulmonary-vascular limitations); breathing reserve, forced expiratory volume in 1 s, and forced vital capacity (mechanical-ventilatory limitations); and peak oxygen uptake, O 2 uptake/work rate slope, and % change of the latter (cardiocirculatory limitations). Thresholds differentiating between different limitation severities were reported. The accuracy of the most accurate decision tree of each category was comparable to expert ratings. Finally, a combined decision tree was created quantifying combined system limitations within one patient. Machine learning-based algorithms may be a viable option to facilitate the interpretation of CPET and identify exercise limitations. Our findings may further support clinical decision making and aid the development of standardized rating instruments.

Cardiorespiratory fitness components in relation to clinical characteristics, disease state and medication intake: A patient registry study.

Interpretation of cardiopulmonary exercise testing (CPET) results requires thorough understanding of test confounders such as anthropometrics, comorbidities and medication. Here, we comprehensively assessed the clinical determinants of cardiorespiratory fitness and its components in a heterogeneous patient sample. We retrospectively collected medical and CPET data from 2320 patients (48.2% females) referred for cycle ergometry at the University Hospital Leuven, Belgium. We assessed clinical determinants of peak CPET indexes of cardiorespiratory fitness (CRF) and its hemodynamic and ventilatory components using stepwise regression and quantified multivariable-adjusted differences in indexes between cases and references. Lower peak load and peak O2 uptake were related to: higher age, female sex, lower body height and weight, and higher heart rate; to the intake of beta blockers, analgesics, thyroid hormone replacement and benzodiazepines; and to diabetes mellitus, chronic kidney disease, non-ST elevation myocardial infarction and atrial fibrillation (p < 0.05 for all). Lower peak load also correlated with obstructive pulmonary diseases. Stepwise regression revealed associations of hemodynamic and ventilatory indexes (including heart rate, O2 pulse, systolic blood pressure and ventilation at peak exercise and ventilatory efficiency) with age, sex, body composition and aforementioned diseases and medications. Multivariable-adjusted differences in CPET metrics between cases and controls confirmed the associations observed. We described known and novel associations of CRF components with demographics, anthropometrics, cardiometabolic and pulmonary diseases and medication intake in a large patient sample. The clinical implications of long-term noncardiovascular drug intake for CPET results require further investigation.

Integrative Interpretation of Cardiopulmonary Exercise Tests for Cardiovascular Outcome Prediction: A Machine Learning Approach.

Integrative interpretation of cardiopulmonary exercise tests (CPETs) may improve assessment of cardiovascular (CV) risk. Here, we identified patient phenogroups based on CPET summary metrics and evaluated their predictive value for CV events. We included 2280 patients with diverse CV risk who underwent maximal CPET by cycle ergometry. Key CPET indices and information on incident CV events (median follow-up time: 5.3 years) were derived. Next, we applied unsupervised clustering by Gaussian Mixture modeling to subdivide the cohort into four male and four female phenogroups solely based on differences in CPET metrics. Ten of 18 CPET metrics were used for clustering as eight were removed due to high collinearity. In males and females, the phenogroups differed significantly in age, BMI, blood pressure, disease prevalence, medication intake and spirometry. In males, phenogroups 3 and 4 presented a significantly higher risk for incident CV events than phenogroup 1 (multivariable-adjusted hazard ratio: 1.51 and 2.19; p ≤ 0.048). In females, differences in the risk for future CV events between the phenogroups were not significant after adjustment for clinical covariables. Integrative CPET-based phenogrouping, thus, adequately stratified male patients according to CV risk. CPET phenomapping may facilitate comprehensive evaluation of CPET results and steer CV risk stratification and management.

A Systematic Approach for the Interpretation of Cardiopulmonary Exercise Testing in Children with Focus on Cardiovascular Diseases

Cardiopulmonary exercise testing (CPET) is the clinical standard for children with congenital heart disease (CHD), heart failure (HF) being assessed for transplantation candidacy, and subjects with unexplained dyspnea on exertion. Heart, lung, skeletal muscle, peripheral vasculature, and cellular metabolism impairment frequently lead to circulatory, ventilatory, and gas exchange abnormalities during exercise. An integrated analysis of the multi-system response to exercise can be beneficial for differential diagnosis of exercise intolerance. The CPET combines standard graded cardiovascular stress testing with simultaneous ventilatory respired gas analysis. This review addresses the interpretation and clinical significance of CPET results with specific reference to cardiovascular diseases. The diagnostic values of commonly obtained CPET variables are discussed using an easy-to-use algorithm for physicians and trained nonphysician personnel in clinical practice.

Cardiopulmonary Exercise Testing Interpretation in Athletes: What the Cardiologist Should Know.

The noninvasive assessment of oxygen consumption, carbon dioxide production, and ventilation during a cardiopulmonary exercise test (CPET) provides insight into the cardiovascular, pulmonary, and metabolic system's ability to respond to exercise. Exercise physiology has been shown to be distinct for competitive athletes and highly active persons (CAHAPs), thus creating more nuanced interpretations of CPET parameters. CPET in CAHAP is an important test that can be used for both diagnosis (provoking symptoms during a truly maximal test) and performance.

Pediatric Cardiopulmonary Exercise Testing: Interoperability Through Domain Analysis Modeling and a National Survey.

The electronic health record, data science advances, and dynamic environmental and infectious threats to child health highlight the need for harmonized and interoperable approaches to pediatric cardiopulmonary exercise testing (CPET). Accordingly, we developed a terminology harmonization in exercise medicine and exercise science domain analysis model (THEMES DAM) to structure CPET data elements. THEMES DAM identified 114 data elements, including participant information, calibration, equipment, protocols, laboratory personnel, encouragement strategies, and analysis procedures. We used the THEMES DAM, vetted by the international data standards organization HL7, to construct a current-state survey of pediatric CPET centers in the United States. Forty-eight of 101 centers responded to a questionnaire covering seven major topic areas (38 items). Centers predominantly performed between 100 and 500 tests annually. Cardiac disease represented 55% of referrals. Almost all centers calibrated gas concentrations and flow daily, but 42% never calibrated their treadmill or cycle ergometers. All centers measured V̇O2peakbut calculated differently. Centers used a variety of protocols (e.g., for treadmill: 61%, Bruce; 43%, modified Bruce; 59%, other); 44% calculated CPET slopes from submaximal portions of CPET (e.g., V̇O2-HR). All centers verbally encouraged participants, but only 40% used a standardized approach. The interpretation of CPET was done by physicians (60%), exercise physiologists (25%), exercise technicians (10%), nurses (1%), or others (4%). Ninety-one percent would agree to collaborate in multicenter research, 89% to establish dynamic reference values, and 83% to better interpret CPET. The survey data and the implementation of THEMES DAM could accelerate interoperability across multiple centers. This would facilitate a nimble approach to create pediatric reference values responsive to the constantly changing health environment and stimulate novel approaches to CPET research and clinical application.

Normative cardiopulmonary exercise data for endurance athletes: the Cardiopulmonary Health and Endurance Exercise Registry (CHEER).

Accurate interpretation of cardiopulmonary exercise testing (CPET) relies on age, gender, and exercise modality-specific reference values. To date, clinically applicable CPET reference values derived from a source population of endurance athletes (EAs) have been lacking. The purpose of this study was to generate CPET reference values for use in the clinical assessment of EA. Prospective data accrued during the clinical care of healthy EA were used to derive CPET reference values and to develop novel equations for V˙O2peak. The performance of these equations was compared to the contemporary standard of care equations and assessed in a discrete EA validation cohort. A total of 272 EA (age = 42 ± 15 years, female = 31%, V˙O2peak = 3.6 ± 0.83 L/min) met inclusion criteria and comprised the derivation cohort. V˙O2peak prediction equations derived from general population cohorts described a modest amount of V˙O2peak variability [R2 = 0.58-0.70, root mean square error (RMSE) = 0.46-0.54 L/min] but were mis-calibrated (calibration-in-the-large = 0.45-1.18 L/min) among EA leading to significant V˙O2peak underestimation. Newly derived, externally validated V˙O2peak prediction equations for EA that included age, sex, and height for both treadmill (R2 = 0.74, RMSE = 0.42 L/min) and cycle ergometer CPET (Cycle: R2 = 0.69, RMSE = 0.42 L/min) demonstrated improved accuracy. Commonly used V˙O2peak prediction equations derived from general population cohorts perform poorly among competitive EA. Newly derived CPET reference values including novel V˙O2peak prediction equations may improve the clinical utility of CPET in this rapidly growing patient population.

Dynamic physiological responses in obese and non-obese adults submitted to cardiopulmonary exercise test.

PurposeObese individuals have reduced performance in cardiopulmonary exercise testing (CPET), mainly considering peak values of variables such as oxygen uptake (), carbon dioxide production (), tidal volume (Vt), minute ventilation () and heart rate (HR). The CPET interpretation and prognostic value can be improved through submaximal ratios analysis of key variables like , , and oxygen uptake efficiency slope (OUES). The obesity influence on these responses has not yet been investigated. Our purpose was to evaluate the influence of adulthood obesity on maximal and submaximal physiological responses during CPET, emphasizing the analysis of submaximal dynamic variables.MethodsWe analyzed 1,594 CPETs of adults (755 obese participants, Body Mass Index ≥ 30 kg/m2) and compared the obtained variables among non-obese (normal weight and overweight) and obese groups (obesity classes I, II and III) through multivariate covariance analyses.ResultObesity influenced the majority of evaluated maximal and submaximal responses with worsened CPET performance. Cardiovascular, metabolic and gas exchange variables were the most influenced by obesity. Other maximal and submaximal responses were altered only in morbidly obese. Only a few cardiovascular and ventilatory variables presented inconsistent results. Additionally, Vtmax, , Vt/Inspiratory Capacity, Vt/Forced Vital Capacity, Lowest , , and the y-intercepts of did not significantly differ regardless of obesity.ConclusionObesity expressively influences the majority of CPET variables. However, the prognostic values of the main ventilatory efficiency responses remain unchanged. These dynamic responses are not dependent on maximum effort and may be useful in detecting incipient ventilatory disorder. Our results present great practical applicability in identifying exercise limitation, regardless of overweight and obesity.

A Machine Learning Approach to the Interpretation of Cardiopulmonary Exercise Tests: Development and Validation.

Objective At present, there is no consensus on the best strategy for interpreting the cardiopulmonary exercise test's (CPET) results. This study is aimed at assessing the potential of using computer-aided algorithms to evaluate CPET data for identifying chronic heart failure (CHF) and chronic obstructive pulmonary disease (COPD). Methods Data from 234 CPET files from the Pulmonary Institute, at Sheba Medical Center, and the Givat-Washington College, both in Israel, were selected for this study. The selected CPET files included patients with confirmed primary CHF (n = 73), COPD (n = 75), and healthy subjects (n = 86). Of the 234 CPETs, 150 (50 in each group) tests were used for the support vector machine (SVM) learning stage, and the remaining 84 tests were used for the model validation. The performance of the SVM interpretive module was assessed by comparing its interpretation output with the conventional clinical diagnosis using distribution analysis. Results The disease classification results show that the overall predictive power of the proposed interpretive model ranged from 96% to 100%, indicating very high predictive power. Furthermore, the sensitivity, specificity, and overall precision of the proposed interpretive module were 99%, 99%, and 99%, respectively. Conclusions The proposed new computer-aided CPET interpretive module was found to be highly sensitive and specific in classifying patients with CHF or COPD, or healthy. Comparable modules may well be applied to additional and larger populations (pathologies and exercise limitations), thereby making this tool powerful and clinically applicable.

Cardiopulmonary exercise testing in repaired tetralogy of Fallot: a valuable tool for pulmonary regurgitation severity assessment

Abstract Funding Acknowledgements Type of funding sources: None. Introduction and purpose The optimal timing for pulmonary valve replacement (PVR) in asymptomatic patients with repaired tetralogy of Fallot (TOF) and pulmonary regurgitation (PR) remains uncertain but is often guided by imaging characterization of the right ventricle. As cardiopulmonary exercise testing (CPET) performance is an accessible prognostic indicator, we assessed which CPET parameters best correlate with pulmonary regurgitation severity to potentially improve identification of high-risk patients. Methods A retrospective chart review was done from 2009 to 2018 on adult patients with repaired TOF who underwent maximal effort cardiopulmonary exercise testing with cycle ergometry and with concurrent pulmonary function testing. Demographics, standard measures of CPET interpretation, and major cardiovascular outcomes were collected. Results Cardiopulmonary exercise testing was performed in 54 adult repaired TOF patients (59% male), with a mean follow-up of 60 ± 33 months. The mean age was 34 ± 9 years. 30 patients (56%) had severe pulmonary regurgitation and 26 patients (48%) were submitted to PVR, with a 0% mortality rate. PVR was performed a mean 28 ± 7 years after TOF repair surgery. There was moderate to severe right ventricular dysfunction in 11 patients (20%). 12 patients (22%) had a hospitalization for heart failure. Arrhythmic events occurred in 9 patients (17%), mainly atrial fibrillation or atrial flutter (67%). 2 patients (4%) received an implantable cardioverter-defibrillator for secondary prevention of sudden cardiac death. Peak VO2 consumption (pVO2) showed no statistically significant correlation with severity of pulmonary regurgitation (HR 0.26, 95% CI 0.879-1.036, p= 0.262) or PVR (HR 0.92, 95% CI 0.829-1.028, p = 0.914), while percent of predicted pVO2 significantly correlated with severity of pulmonary regurgitation (HR 0.95, 95% CI 0.918-0.993, p = 0.020) and PVR (HR 0.94, 95% CI 0.886-0.992, p = 0.025). VE/VCO2 slope was not a significant predictor of severity of pulmonary regurgitation (HR 1.03, 95% CI 0.929-1.130, p = 0.622) or PVR (HR 1.04, 95% CI 0.952-1.128, p = 0.414) or) and neither cardiorespiratory optimal point (HR 0.94, 95% CI 0.786-1.120, p = 0.480) nor maximum end-tidal carbon dioxide pressure (PETCO2) (HR 0.93, 95% CI 0.846-1.037, p = 0.213) correlated with severity of pulmonary regurgitation or PVR. Conclusion Percent of predicted peak VO2 had the highest predictive power of all CPET parameters analysed in adult repaired TOF patients. Preoperative CPET could be an accessible way to identify high-risk patients earlier for PVR and should therefore be included in the routine assessment of these patients.

Clinical Interpretation of Cardiopulmonary Exercise Testing: Current Pitfalls and Limitations.

Several shortcomings on cardiopulmonary exercise testing (CPET) interpretation have shed a negative light on the test as a clinically useful tool. For instance, the reader should recognize patterns of dysfunction based on clusters of variables rather than relying on rigid interpretative algorithms. Correct display of key graphical data is of foremost relevance: prolixity and redundancy should be avoided. Submaximal dyspnea ratings should be plotted as a function of work rate (WR) and ventilatory demand. Increased work of breathing and/or obesity may normalize peak oxygen uptake (V̇O2) despite a low peak WR. Among the determinants of V̇O2, only heart rate is measured during non-invasive CPET. It follows that in the absence of findings suggestive of severe impairment in O2 delivery, the boundaries between inactivity and early cardiovascular disease are blurred in individual subjects. A preserved breathing reserve should not be viewed as evidence that “the lungs” are not limiting the subject. In this context, measurements of dynamic inspiratory capacity are key to uncover abnormalities germane to exertional dyspnea. A low end-tidal partial pressure for carbon dioxide may indicate either increased “wasted” ventilation or alveolar hyperventilation; thus, direct measurements of arterial (or arterialized) PO2 might be warranted. Differentiating a chaotic breathing pattern from the normal breath-by-breath noise might be complex if the plotted data are not adequately smoothed. A sober recognition of these limitations, associated with an interpretation report free from technicalities and convoluted terminology, is crucial to enhance the credibility of CPET in the eyes of the practicing physician.

Normative Peak Cardiopulmonary Exercise Test Responses in Canadian Adults Aged ≥40 Years

Up-to-date normative reference sets for cardiopulmonary exercise testing (CPET) are important to aid in the accurate interpretation of CPET in clinical or research settings. This study aimed to (1) develop and externally validate a contemporary reference set for peak CPET responses in Canadian adults identified with population-based sampling; and (2) evaluate previously recommended reference equations for predicting peak CPET responses. Participants were healthy adults who were≥40 years old from the Canadian Cohort Obstructive Lung Disease who completed an incremental cycle CPET. Prediction models for peak CPET responses were estimated from readily available participant characteristics (age, sex, height, body mass) with the use of quantile regression. External validation was performed with a second convenience sample of healthy adults. Peak CPET parameters that were measured and predicted in the validation cohort were assessed for equivalence (two one-sided tests of equivalence for paired-samples and level of agreement (Bland-Altman analyses). Two one-sided tests of equivalence for paired samples assessed differences between responses in the derivation cohort using previously recommended reference equations. Normative reference ranges (5th-95th percentiles) for 28 peak CPET parameters and prediction models for 8 peak CPET parameters were based on 173 participants (47%male) who were 64 ± 10 years old. In the validation cohort (n= 84), peak CPET responses that were predicted with the newly generated models were equivalent to the measured values. Peak cardiac parameters predicted by the previously recommended reference equations by Jones and colleagues and Hansen and colleagues were significantly higher. This study provides reference ranges and prediction models for peak cardiac, ventilatory, operating lung volume, gas exchange, and symptom responses to incremental CPET and presents the most comprehensive reference set to date in Canadian adults who were≥40 years old to be identified with population-based sampling.

Cardiopulmonary Exercise Testing in Patients With Interstitial Lung Disease.

Interstitial lung disease (ILD) is a heterogeneous group of conditions characterized by fibrosis and/or inflammation of the lung parenchyma. The pathogenesis of ILD consistently results in exertional dyspnea and exercise intolerance. Cardiopulmonary exercise testing (CPET) provides important information concerning the pathophysiology of ILD that can help inform patient management. Despite the purported benefits of CPET, its clinical utility in ILD is not well defined; however, there is a growing body of evidence that provides insight into the potential value of CPET in ILD. Characteristic responses to CPET in patients with ILD include exercise-induced arterial hypoxemia, an exaggerated ventilatory response, a rapid and shallow breathing pattern, critically low inspiratory reserve volume, and elevated sensations of dyspnea and leg discomfort. CPET is used in ILD to determine cause(s) of symptoms such as exertional dyspnea, evaluate functional capacity, inform exercise prescription, and determine the effects of pharmacological and non-pharmacological interventions on exercise capacity and exertional symptoms. However, preliminary evidence suggests that CPET in ILD may also provide valuable prognostic information and can be used to ascertain the degree of exercise-induced pulmonary hypertension. Despite these recent advances, additional research is required to confirm the utility of CPET in patients with ILD. This brief review outlines the clinical utility of CPET in patients with ILD. Typical patterns of response are described and practical issues concerning CPET interpretation in ILD are addressed. Additionally, important unanswered questions relating to the clinical utility of CPET in the assessment, prognostication, and management of patients with ILD are identified.

The Personalized Precise Exercise Training with Holistic Integrative Protocol (PPET‐HIP) for Effective Management in Patient with Chronic Diseases (CDs)

BACKGROUNDThe patients with chronic diseases (CDs, i.e. hypertension, hyperglycemia, hyperlipidemia, hyperuricemia and obesity etc. with or without MI or Stoke) were uncured, according to the guidelines of all each one group of exports. However, based on our new Holistic Integrative Physiology and Medicine (HIPM), we might be able to use the core personalized precise exercise training and continuous functional monitoring with holistic integrative protocol (PPET‐HIP) for effective management of CDs patients.METHODSTen CDs patients, who has more than 10–30year history and four of them had MI or Stoke, were recruited from 2014–2018.Before and after 12‐week intervention, general evaluations(blood pressure, glucose, and lipid profiles), cardiopulmonary exercise testing (CPET), echocardiogram, and the adjustment of drugs treated CDs patients were recorded respectively. Based on HIPM for CPET interpretation, we gave each patient an PPET‐HIP for adjusting of all life styles.RESULTSAll patients exercised safely with any problem. After 12w HIPM‐PPT management, the all abnormal parameters of hypertensive, hyperglycemia, hyperlipidemia, hyperuricemia and obesity were become normal; CPET parameters, left ventricular function, and QoL were improved significantly than those before (P&lt;0.05). Then we decreased drugs dosages and totally stopped drugs, the levels of blood pressure, glucose and lipid were still maintained stable. Surprisingly, the curable condition was achieved in CDs patients.CONCLUSIONSHIPM guiding CPET for the PPET‐HIP could safely and effectively control the conditions of patients with CDs.Support or Funding InformationNational Natural Science Foundation of China (81470204);Fuwai Hospital, National Cardiovascular Institute of Chinese Academy of Medical Sciences (2012‐YJR02);Research on Clinical Characteristics of the Capital (Z141107002514084);Research and Outcome Promotion of Clinical Characteristics in the Capital (Project No. Z161100000516127)

Guidance to the Interpretation of Cardiopulmonary Exercise Testing

Cardiorespiratory fitness has been established as an independent overall predictor of morbidity and mortality. However, patients' symptoms or stated levels of exercise intolerance correlate only poorly with resting functional and imaging tests. Cardiopulmonary exercise testing (CPET) is the gold standard for the integrative assessment of the cardiocirculatory, pulmonary and metabolic response to exercise and can help identify the source of exercise limitation, monitor disease progression, evaluate treatment responsiveness and inform about prognosis. Though CPET offers more valuable and pertinent information with slightly more expenditure of time compared to other methods even at submaximal exercise levels, it remains underutilized for various reasons such as costs, reimbursement and expertise. CPET can be seen as a complex, but not necessarily difficult tool. The objective of this review was to provide a description of the underlying principles of physiology, and an easy-to-follow guidance to indications, methodology, and interpretative strategies of CPET.

Reference values for aerobic capacity estimated by cardiopulmonary exercise test on a cycle ergometer in a healthy Greek population

ObjectiveAerobic capacity (AC) is inversely associated with a high risk of cardiovascular morbidity and mortality as well as all-cause mortality. Cardiopulmonary exercise testing (CPET) represents the gold standard for assessing exercise capacity based on maximum oxygen uptake (VO2max). The purpose of our study was to provide for the first time CPET-derived normative reference values in a Greek cohort of apparently healthy men and women on a cycle ergometer to evaluate their AC, and to compare our results with similar studies from other countries. MethodsA cohort of 194 apparently healthy subjects (118 males and 76 females, age range, 15-69 years) was submitted to CPET using a cycle ergometer. Mean ± SD values for several exercise parameters, VO2max included, were determined. We compared our results with existing data derived from USA and North Europe cohorts. ResultsMale subjects achieved significantly higher levels of relative and absolute VO2max (p < 0.001) across all ages compared to female subjects. A decline in relative and absolute VO2max among older participants was observed in both sexes. Greek subjects had lower AC than the North Europe cohort and almost similar to the USA cohort. ConclusionWe provide the first reference data for AC in apparently healthy Greek subjects based on CPET using cycle ergometer. Our findings will allow for more accurate interpretation of CPET in several groups of healthy subjects or patients with CV diseases. The differences found between our reference values and those reported from the USA and northern European countries, underscore the need for individual countries to develop their own AC reference values.

Cardiopulmonary Exercise Testing-A Valuable Tool, Not Gatekeeper When Referring Patients With Adult Congenital Heart Disease for Transplant Evaluation.

Treatment of patients with adult congenital heart disease (ACHD) with advanced therapies including heart transplant (HT) is often delayed due to paucity of objective prognostic markers for the severity of heart failure (HF). While the utility of Cardiopulmonary Exercise Testing (CPET) in non-ACHD patients has been well-defined as it relates to prognosis, CPET for this purpose in ACHD is still under investigation. We performed a retrospective cohort study of 20 consecutive patients with ACHD who underwent HT between March 2010 and February 2016. Only 12 of 20 patients underwent CPET prior to transplantation. Demographics, standard measures of CPET interpretation, and 30-day and 1-year post transplantation outcomes were collected. Patient Characteristics. Twenty patients with ACHD were transplanted at a median of 40 years of age (range: 23-57 years). Of the 12 patients who underwent CPET, 4 had undergone Fontan procedures, 4 had tetralogy of Fallot, 3 had d-transposition of the great arteries, and 1 had Ebstein anomaly. Thirty-day and one-year survival was 100%. All tests included in the analysis had a peak respiratory quotient _1.0. The median peak oxygen consumption per unit time (_VO2) for all diagnoses was 18.2 mL/kg/min (46% predicted), ranging from 12.2 to 22.6. There is a paucity of data to support best practices for patients with ACHD requiring transplantation. While it cannot be proven based on available data, it could be inferred that outcomes would have been worse or perhaps life sustaining options unavailable if providers delayed referral because of the lack of attainment of CPET-specific thresholds.