Category Archives: Abstracts

Accuracy of respiratory gas variables, substrate, and energy use from 15 CPET systems during simulated and human exercise

Bas Van Hooren; Tjeu Souren; Bart C. Bongers;  (Maastricht University, Maastricht, The Netherlands)

Scand J Med Sci Sports. 2023;00:1–21.

Purpose: Various systems are available for cardiopulmonary exercise testing (CPET), but their accuracy remains largely unexplored. We evaluate the accuracy of 15 popular CPET systems to assess respiratory variables, substrate use, and energy expenditure during simulated exercise. Cross-comparisons were also per- formed during human cycling experiments (i.e., verification of simulation find- ings), and between-session reliability was assessed for a subset of systems.
Methods: A metabolic simulator was used to simulate breath-by-breath gas exchange, and the values measured by each system (minute ventilation [V̇E], breathing frequency [BF], oxygen uptake [V̇O2], carbon dioxide production [V̇CO2], respiratory exchange ratio [RER], energy from carbs and fats, and total energy expenditure) were compared to the simulated values to assess the accu- racy. The following manufacturers (system) were assessed: COSMED (Quark CPET, K5), Cortex (MetaLyzer 3B, MetaMax 3B), Vyaire (Vyntus CPX, Oxycon Pro), Maastricht Instruments (Omnical), MGC Diagnostics (Ergocard Clinical, Ergocard Pro, Ultima), Ganshorn/Schiller (PowerCube Ergo), Geratherm (Ergostik), VO2master (VO2masterPro), PNOĒ (PNOĒ), and Calibre Biometrics (Calibre).
Results: Absolute percentage errors during the simulations ranged from 1.15%– 50.3% for V̇E, 1.05–3.79% for BF, 1.10%–17.5% for V̇O2, 1.07%–18.3% for V̇CO2, 0.62%–14.8% for RER, 5.52%–99.0% for Kcal from carbs, 5.13%–133% for Kcal from fats, and 0.59%–12.1% for total energy expenditure. Between-session vari- ation ranged from 0.86%–22.4% for V̇O2 and 1.14%–20.2% for V̇CO2, respectively.
Conclusion: The error of respiratory gas variables, substrate, and energy use differed substantially between systems, with only a few systems demonstrating a consistent acceptable error. We extensively discuss the implications of our findings for clinicians, researchers and other CPET users.

Identification of Subclinical Heart Failure With Preserved Ejection Fraction in Patients With Symptomatic Atrial Fibrillation

Ariyaratnam JP; Elliott AD; Mishima RS; Kadhim K; McNamee O; Kuklik P; Emami M; Malik V; Fitzgerald JL; Gallagher C; Lau DH; Sanders P;

JACC. Heart failure [JACC Heart Fail] 2023 Aug 21.
Date of Electronic Publication: 2023 Aug 21.

Background: Atrial fibrillation (AF) and heart failure with preserved ejection fraction (HFpEF) commonly coexist. We hypothesize that patients with symptomatic AF but without overt clinical HF commonly exhibit subclinical HFpEF according to established hemodynamic criteria.
Objectives: The authors sought to use invasive hemodynamics to investigate the prevalence and implications of subclinical HFpEF in AF ablation patients.
Methods: Consecutive symptomatic AF ablation patients were prospectively recruited. Diagnosis of subclinical HFpEF was undertaken by invasive assessment of left atrial pressure (LAP). Participants had HFpEF if the baseline mean LAP was >15 mm Hg and early HFpEF if the mean LAP was >15 mm Hg after a 500-mL fluid challenge. LA compliance was assessed invasively by monitoring the LAP and LA diameter during direct LA infusion of 15 mL/kg normal saline. LA compliance was calculated as Δ LA diameter/ΔLAP. LA cardiomyopathy was further studied with exercise echocardiography and electrophysiology study. Functional impact was evaluated using cardiopulmonary exercise testing and the AF Symptom Severity questionnaire.
Results: Of 120 participants, 57 (47.5%) had HFpEF, 31 (25.8%) had early HFpEF, and 32 (26.7%) had no HFpEF. Both HFpEF and early HFpEF were associated with lower LA compliance compared with those without HFpEF (P < 0.001). Participants with HFpEF and early HFpEF also displayed decreased LA emptying fraction (P = 0.004), decreased LA voltage (P = 0.001), decreased VO 2peak (P < 0.001), and increased AF symptom burden (P = 0.002) compared with those without HFpEF.
Conclusions: Subclinical HFpEF is common in AF ablation patients and is characterized by a LA cardiomyopathy, decreased cardiopulmonary reserve and increased symptom burden. The diagnosis of HFpEF may identify patients with AF with the potential to benefit from novel HFpEF therapies. (Characterising Left Atrial Function and Compliance in Atrial Fibrillation; ACTRN12620000639921).
Competing Interests: Funding Support and Author Disclosures Drs Ariyaratnam, Mishima, Kadhim, Emami, Malik, and Fitzgerald are supported by Postgraduate Scholarships from the University of Adelaide. Dr Elliott is supported by a Future Leader Fellowship from the National Heart Foundation of Australia. Dr Gallagher is supported by a Postdoctoral Fellowship from the University of Adelaide. Dr Lau is supported by a Mid-career fellowship from The Hospital Research Foundation. Dr Sanders is supported by a Practitioner Fellowship from the National Health and Medical Research Council of Australia. Dr Lau reports that the University of Adelaide has received on his behalf lecture and/or consulting fees from Abbott Medical, Bayer, Biotronik, BMS Pfizer, Boehringer Ingelheim, Medtronic, and MicroPort CRM. Dr Sanders has served on the advisory board of Medtronic, Abbott Medical, Boston-Scientific, Pacemate, and CathRx. Dr Sanders reports that the University of Adelaide has received on his behalf lecture and/or consulting fees from Medtronic, Boston-Scientific, and Abbott Medical; and reports that the University of Adelaide has received on his behalf research funding from Medtronic, Abbott Medical, Boston Scientific, and Microport CRM. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.

The Current Role of Cardiopulmonary Exercise Test in the Diagnosis and Management of Pulmonary Hypertension.

Pezzuto B; Agostoni P;

Journal of clinical medicine [J Clin Med] 2023 Aug 23; Vol. 12 (17).
Date of Electronic Publication: 2023 Aug 23.

Pulmonary arterial hypertension (PAH) is a progressive disease with a poor prognosis if left untreated. Despite remarkable achievements in understanding disease pathophysiology, specific treatments, and therapeutic strategies, we are still far from a definitive cure for the disease, and numerous evidences have underlined the importance of early diagnosis and treatment to improve the prognosis. Cardiopulmonary exercise testing (CPET) is the gold standard for assessing functional capacity and evaluating the pathophysiological mechanisms underlying exercise limitation. As effort dyspnea is the earliest and one of the main clinical manifestations of PAH, CPET has been shown to provide valid support in early detection, differential diagnosis, and prognostic stratification of PAH patients, being a useful tool in both the first approach to patients and follow-up. The purpose of this review is to present the current applications of CPET in pulmonary hypertension and to propose possible future utilization to be further investigated.

Classification and Predictors of Right Ventricular Functional Recovery in Pulmonary Arterial Hypertension.

Rischard FP; Bernardo RJ; Vanderpool RR; Kwon DH; Acharya T; Park MM; Katrynuik A; Insel M; Kubba S; Badagliacca R; Larive AB; Naeije R;Garcia JGN; Beck GJ; Erzurum SC; Hassoun PM; Hemnes AR; Hill NS; Horn EM; Leopold JA; Rosenzweig EB; Tang WHW; Wilcox JD;

Circulation. Heart failure [Circ Heart Fail] 2023 Sep 04, pp. e010555.
Date of Electronic Publication: 2023 Sep 04.

Background: Normative changes in right ventricular (RV) structure and function have not been characterized in the context of treatment-associated functional recovery (RV functional recovery [RVFnRec]). The aim of this study is to assess the clinical relevance of a proposed RVFnRec definition.
Methods: We evaluated 63 incident patients with pulmonary arterial hypertension by right heart catheterization and cardiac magnetic resonance imaging at diagnosis and cardiac magnetic resonance imaging and invasive cardiopulmonary exercise testing following treatment (≈11 months). Sex, age, ethnicity matched healthy control subjects (n=62) with 1-time cardiac magnetic resonance imaging and noninvasive cardiopulmonary exercise testing were recruited from the PVDOMICS (Redefining Pulmonary Hypertension through Pulmonary Vascular Disease Phenomics) project. We examined therapeutic cardiac magnetic resonance imaging changes relative to the evidence-based peak oxygen consumption (VO 2peak )>15 mL/(kg·min) to define RVFnRec by receiver operating curve analysis. Afterload was measured as mean pulmonary artery pressure, resistance, compliance, and elastance.
Results: A drop in RV end-diastolic volume of -15 mL best defined RVFnRec (area under the curve, 0.87; P =0.0001) and neared upper 95% CI RV end-diastolic volume of controls. This cutoff was met by 22 out of 63 (35%) patients which was reinforced by freedom from clinical worsening, RVFnRec 1 out of 21 (5%) versus no RVFnRec 17 out of 42, 40% (log-rank P =0.006). A therapy-associated increase of 0.8 mL/mm Hg in compliance had the best predictive value of RVFnRec (area under the curve, 0.76; [95% CI, 0.64-0.88]; P =0.001). RVFnRec patients had greater increases in stroke volume, and cardiac output at exercise.
Conclusions: RVFnRec defined by RV end-diastolic volume therapeutic decrease of -15 mL predicts exercise capacity, freedom from clinical worsening, and nears normalization. A therapeutic improvement of compliance is superior to other measures of afterload in predicting RVFnRec. RVFnRec is also associated with increased RV output reserve at exercise.

The evolving role of cardiopulmonary exercise testing in ischemic heart disease – state of the art review.

Chaudhry S; Kumar N; Arena R; Verma S;

Current opinion in cardiology [Curr Opin Cardiol] 2023 Sep 08.
Date of Electronic Publication: 2023 Sep 08.

Purpose of Review: Cardiopulmonary exercise testing (CPET) is the gold standard for directly assessing cardiorespiratory fitness (CRF) and has a relatively new and evolving role in evaluating atherosclerotic heart disease, particularly in detecting cardiac dysfunction caused by ischemic heart disease. The purpose of this review is to assess the current literature on the link between cardiovascular (CV) risk factors, cardiac dysfunction and CRF assessed by CPET.
Recent Findings: We summarize the basics of exercise physiology and the key determinants of CRF. Prognostically, several studies have been published relating directly measured CRF by CPET and outcomes allowing for more precise risk assessment. Diagnostically, this review describes in detail what is considered healthy and abnormal cardiac function assessed by CPET. New studies demonstrate that cardiac dysfunction on CPET is a common finding in asymptomatic individuals and is associated with CV risk factors and lower CRF. This review covers how key CPET parameters change as individuals transition from the asymptomatic to the symptomatic stage with progressively decreasing CRF. Finally, a supplement with case studies with long-term longitudinal data demonstrating how CPET can be used in daily clinical decision making is presented.
Summary: In summary, CPET is a powerful tool to provide individualized CV risk assessment, monitor the effectiveness of therapeutic interventions, and provide meaningful feedback to help patients guide their path to improve CRF when routinely used in the outpatient setting.

Postoperative hyperlactataemia and preoperative cardiopulmonary exercise testing in an elective noncardiac surgical cohort: a retrospective observational study.

Darwen C; MBryan A; Quraishi-Akhtar T; Moore J;

BJA open [BJA Open] 2023 Feb 23; Vol. 5, pp. 100124.
Date of Electronic Publication: 2023 Feb 23 (Print Publication: 2023).

Background: Blood lactate concentration in the postoperative period is a marker of physiological stress and a predictor of complications and mortality. Cardiopulmonary exercise testing (CPET) is a common preoperative risk stratification tool. We aimed to investigate the association between preoperative CPET results and postoperative lactate concentration with postoperative mortality after major noncardiac surgery.
Methods: We analysed data from patients undergoing major noncardiac surgery in a tertiary UK centre between 2007 and 2014 who had preoperative CPET and postoperative lactate measurements. Univariate and multivariate analyses were performed to assess the association between lactate concentration, CPET results, or both and mortality.
Results: We analysed data from 1075 patients. A mean lactate concentration >2 mM in the first 12, 24, and 48 h after surgery was associated with odds ratios (ORs) and 95% confidence intervals (CIs) for 30-day mortality of 3.9 (2.1-7.3; P <0.005), 4.5 (2.4-8.4; P <0.005), and 6.1 (3.3-11.5; P <0.005), respectively. The dichotomous CPET variable, ventilatory equivalence for CO 2 ( E/ co2 ; cut-off 34), was associated with increased risk of 30-day mortality (OR 2.5; 95% CI: 1.3-4.8; P <0.005). In a multivariable model, hyperlactataemia and poor E/ co2 retained their significant associations with 30- and 90-day mortality when adjusted for age, BMI, and surgical risk. When looking at the combined effect of the dichotomous hyperlactataemia in the first 24 h (cut-off 2 mM) and preoperative E/ co2 , the OR for 30-day mortality was 11.53 (95% CI: 4.6-28.8; P ≤0.005).
Conclusions: Our study suggests that postoperative hyperlactataemia and preoperative poor E/ co2 are independently associated with an increased risk of mortality after major noncardiac surgery.

Prognostic value of cardiopulmonary exercise testing repetition during follow-up of clinically stable patients with severe dilated cardiomyopathy. A preliminary study.

Baracchini N; Zaffalon D; Merlo M; Baschino S; Barbati G; Pezzuto B; Capovilla TM; Rossi M; Carriere C; Agostoni P; Sinagra G;

International journal of cardiology [Int J Cardiol] 2023 Aug 08, pp. 131252.
Date of Electronic Publication: 2023 Aug 08.

Background: Cardiopulmonary exercise testing (CPET) is a recognized tool for prognostic stratification in patients with dilated cardiomyopathy (DCM). Given the lack of data currently available, the aim of this study was to test the prognostic value of repeating CPET during the follow-up of patients with DCM.
Methods: This multicenter, retrospective study, analyzed DCM patients who consecutively performed two echocardiographies and CPETs during clinical stability. The study end-point was a composite of death from all causes, heart transplantation, left ventricular assist device implantation, life-threatening ventricular arrhythmias or hospitalization for heart failure.
Results: 216 DCM patients were enrolled (52 years, 78% male, NYHA I-II 82%, LVEF 32%, 94% on ACE inhibitors/ARNI, 95% on beta-blockers). The interval between CPETs was 15 months. During a median follow-up of 38 months from the second CPET, 102 (47%) patients experienced the study end-point. Among them, there was stability of echocardiographic values but a significant worsening of functional capacity. Among the 173 patients (80%) who did not show echocardiographic left ventricular reverse remodeling (LVRR), the 1-year prevalence of the study-end point was higher in patients who worsened vs patients who maintained stable their functional capacity at CPET (38 vs. 15% respectively, p-value: 0.001). These results were consistent also when excluding life-threatening ventricular arrhythmias from the composite end-point.
Conclusion: In clinically stable DCM patients with important depression of LVEF, the repetition of combined echocardiography and CPET might be recommended. When LVRR fails, 1-year repetition of CPET could identify higher-risk patients.

 

Cardiorespiratory fitness in women after severe pre-eclampsia.

Gronningsaeter L; Estensen ME; Skulstad H; Langesaeter E; Edvardsen E;

Hypertension in pregnancy [Hypertens Pregnancy] 2023 Dec; Vol. 42 (1), pp. 2245054.

Aims: To objectively study cardiorespiratory fitness (CRF) and physical activity (PA) and to evaluate limiting factors of exercise intolerance associated with poor CRF after severe pre-eclampsia.
Methods: In this single-centre, cross-sectional study, CRF was measured as peak oxygen uptake (VO 2peak ) during a cardiopulmonary exercise test (CPET) on a treadmill in women 7 years after severe pre-eclampsia. Ninety-six patients and 65 controls were eligible to participate. Cardiac output (CO) was measured by impedance cardiography. PA was measured using accelerometers.
Results: In 62 patients and 35 controls (mean age 40 ± 3 years), the VO 2peak (in mL·kg-1·min-1) values were 31.4 ± 7.2 and 39.1 ± 5.4, respectively (p<0.01). In the patients, the COpeak was (9.6 L·min-1), 16% lower compared to controls (p<0.01). Twelve patients (19%) had a cardiac limitation to CPET. Twenty-three (37%) patients and one (3%) control were classed as unfit, with no cardiopulmonary limitations. The patients demonstrated 25% lower PA level (in counts per minute; p<0.01) and 14% more time being sedentary (p<0.01), compared with the controls. Twenty-one patients (34%) compared with four (17%) controls did not meet the World Health Organization’s recommendations for PA (p=0.02). Body mass index and PA level accounted for 65% of the variability in VO 2peak .
Conclusion: Significantly lower CRF and PA levels were found in patients on long-term follow-up after severe pre-eclampsia. CPET identified cardiovascular limitations in one third of patients. One third appeared unfit, with adiposity and lower PA levels. These findings highlight the need for clinical follow-up and exercise interventions after severe pre-eclampsia.

Down-staging of obesity one year after bariatric surgery: a new proposal of Edmonton obesity staging system.

Quinto G; Bettini S; Neunhaeuserer D; Battista F; SMilan G; Gasperetti A; Vecchiato M; Vettor R; Ermolao A; Busetto L;

Frontiers in endocrinology [Front Endocrinol (Lausanne)] 2023 Jul 21; Vol. 14, pp. 1147171.
Date of Electronic Publication: 2023 Jul 21 (Print Publication: 2023).

Background: Different approaches are used to classify obesity severity. The Edmonton Obesity Staging System (EOSS) considers medical, physical and psychological parameters. A new modified EOSS with a different functional evaluation method, measuring Cardiorespiratory Fitness (CRF), has been recently proposed, EOSS-CRF. Bariatric surgery (BS) is one of the most efficient treatments of obesity and all aspect of related disorders. No studies have yet applied EOSS-CRF after BS. Therefore, the aim of this study was to evaluate modifications in EOSS and EOSS-CRF before and after BS.
Methods: This observational study finally enrolled 72 patients affected by obesity. A multi-disciplinary assessment in order to evaluate eligibility to surgical treatment has been performed, including anamnesis, physical evaluation, anthropometric data measurement, biochemical blood exams and cardiopulmonary exercise testing. One year after BS the same protocol was applied. Patients have been classified according to EOSS and EOSS-CRF before and one year after BS.
Results: After BS, patients categorized in classes associated to severe obesity (EOSS ≥ 2 or EOSS-CRF ≥ 2) reduced significantly. Using EOSS, patients without functional impairment were 61% before surgery and 69% after BS (p=0.383). Using EOSS-CRF, patients considered without functional impairment were only 9.7% before BS; this percentage significantly raised to 50% after BS (p<0.001). The impact of functional domains before and after BS is different in grading patients in EOSS and EOSS-CRF, respectively.
Conclusions: Improvements obtained after BS are adequately summarized by EOSS and EOSS-CRF. The EOSS-CRF grading method for functional impairment seems to better reflect the known amelioration obtained after BS. Objective measurements of CRF may provide additional value to classify severity of obesity, also in the follow-up after BS.

Effect of tele-yoga on aerobic capacity, respiratory muscle strength, and cognitive performance in patients with obstructive sleep apnea syndrome.

Eyuboglu F; Inal-Ince D; Karamancioglu B;Vardar-Yagli N; Kaya-Utlu D; Dalkilic O; Somay G;

Heart & lung : the journal of critical care [Heart Lung] 2023 Aug 01; Vol. 62, pp. 157-167.
Date of Electronic Publication: 2023 Aug 01.

Background: Obstructive sleep apnea syndrome (OSAS) causes a decrease in aerobic capacity, respiratory muscle strength, and cognitive function, negatively affecting health-related quality of life.
Objectives: This study aimed to compare aerobic capacity, respiratory muscle strength, cognitive performance, functional capacity, sleep quality and daytime sleepiness in OSAS patients practicing and not practicing tele-yoga (TY).
Methods: 44 OSAS patients (40 M, 4F) were randomized into TY and control groups. TY group underwent live synchronous group-based TY sessions, 60 min/day, three days/week, for 12 weeks. Control group performed unsupervised thoracic expansion exercises at home 4 times daily for 12 weeks. The following were evaluated at baseline and at the end of the 6th and 12th weeks: inspiratory and expiratory respiratory muscle strength (MIP, MEP), cardiopulmonary exercise test, Corsi Block Tapping Test (CBTT) and Stroop TBAG test, six-minute walk test (6MWT), Pittsburgh Sleep Quality Index (PSQI) and Epworth Sleepiness Scale (ESS).
Results: TY significantly improved MIP, and exercise test parameters (VE, HR max ,%HR, heart rate recovery in the first minute and RQ max ), CBTT (forward) and Stroop TBAG test scores (parts of 3,4,5) compared to the controls (p<0.05). There were no significant changes 6MWT in the TY group compared to the control group (p > 0.05). Sleep duration (min), sleep efficiency, sleep quality of PSQI and ESS score improved significantly in the TY group compared to the control group (p < 0.05).
Conclusion: We suggest including TY intervention as a method of exercise in addition to CPAP treatments since it improves the health-related parameters of OSAS patients.