Cardiopulmonary Exercise Testing Variables Research Articles

(Non)-Exertional Variables of Cardiopulmonary Exercise Testing in Heart Failure with and Without Cardiac Amyloidosis.

Cardiac amyloidosis (CA) constitutes an important etiology of heart failure with preserved ejection fraction (HFpEF) or heart failure with mildly reduced ejection fraction (HFmrEF). Since patients with CA show early exhaustion, we aimed to investigate whether non-exertional variables of cardiopulmonary exercise testing (CPET) provide additional information in comparison to traditional peak oxygen consumption (VO2peak). We retrospectively investigated CPET variables of patients with HFpEF and HFmrEF with (n = 21) and without (n = 21, HF) CA at comparable age and ejection fraction. Exertional and non-exertional CPET variables as well as laboratory and echocardiographic markers were analyzed. The primary outcome was the difference in CPET variables between groups. The secondary outcome was rehospitalization in patients with CA during a follow-up of 24months. Correlations between CPET, NTproBNP, and echocardiographic variables were calculated to detect patterns of discrimination between the groups. HF patients with CA were inferior to controls in most exertional and non-exertional CPET variables. Patients with CA were hospitalized more often (p = 0.002), and rehospitalization was associated with VE/VCO2 (p = 0.019), peak oxygen pulse (p = 0.042), the oxygen equivalent at the first ventilatory threshold (p = 0.003), circulatory (p = 0.024), and ventilatory power (p < .001), but not VO2peak (p = 0.127). Higher performance was correlated with lower E/e' and NTproBNP as well as higher resting heart rate and stroke volume in CA. Patients with CA displayed worse non-exertional CPET performance compared to non-CA HF patients, which was associated with rehospitalization. Differences between correlations of resting echocardiography and CPET variables between groups emphasize different properties of exercise physiology despite comparable ejection fraction.

O220: The role of cardiopulmonary exercise testing in predicting sarcopenia after neoadjuvant chemotherapy and post-operative complications

Abstract Background Neoadjuvant chemotherapy (NAC) may contribute to sarcopenia development in patients with oesophageal and oesophagogastric junction (OGJ) adenocarcinoma. Preoperative cardiopulmonary fitness and sarcopenia are both variables which have been correlated with outcomes after major surgery. The aims of this study were to investigate if pre-operative cardiopulmonary exercise testing (CPET) variables were associated with radiological sarcopenia post NAC, and the effect of CPET variables on post-operative outcomes in sarcopenic patients. Methods Patients from a single high-volume tertiary centre diagnosed with oesophageal or OGJ adenocarcinoma between August 2015 and August 2022 were included. CPET variables and post-NAC CT scans to assess for radiological sarcopenia were evaluated. CPET variables included in statistical analyses were ventilatory equivalent for carbon dioxide (VE/VCO2), anaerobic threshold (AT) and peak oxygen consumption (VO2 peak). Results 208 patients were included. Median VE/VCO2 was 29 in patients with sarcopenia post-NAC and 28 in non-sarcopenic patients (p = 0.009). Other CPET variables were not associated with sarcopenia post NAC. Within the sarcopenic group, CPET variables were not associated with post-operative complications. Within the whole cohort, increased VE/VCO2 or decreased VO2 peak correlated with a longer hospital stay (p=0.043 and p=0.012 respectively), and an association was observed between VE/VCO2 and Clavien-Dindo grade of complications (p=0.019). Conclusions VE/VCO2 was associated with sarcopenia post NAC in patients with oesophageal and OGJ adenocarcinoma. Further analysis with a larger sample size might help establish this, which could be helpful in identifying and targeting patients at higher risk of sarcopenia and post-operative complications.

Predischarge oxygen uptake efficiency slope has short and long-term value in the prognosis of patients after acute myocardial infarction.

Patients who survive an acute myocardial infarction (AMI) have a higher risk of having a major cardiovascular event (MACE). Cardiopulmonary exercise testing (CPET) could develop prognostic stratification and prescribing exercise prescription. Patients after AMI frequently terminate CPET early with submaximal testing results. We aimed to look at the characteristics of patients' predischarge CPET variables after AMI intervention and find potential CPET variables with prognostic value. Between July 2012 and August 2017, we recruited patients who survived first AMI after primary percutaneous coronary intervention and received predischarge CPET retrospectively in a tertiary medical center of Taiwan. Patients were followed-up on a MACE or administrative censoring occurred (up to 5 years). To identify significant predictors of a MACE, a Cox regression model was used. One hundred thirteen patients (103 men and 10 women) were studied, with an average age of 58.32 ± 12.49. MACE over 3 months, 2-years, and 5-years was 17.70%, 53.10%, and 62.83%, respectively. The oxygen uptake efficiency slope during the whole during of CPET (OUES 100) divided by body surface area (OUES 100/BSA) was found to be a significant event predictor for MACE at 3-month, 2- and 5-years. Cox regression analysis revealed that those with OUES 100/BSA <0.722 ( p = 0.004), OUES 100/BSA <0.859 ( p = 0.002), and OUES 100/BSA <0.829 ( p = 0.002) had a 7.14-fold, 3.47-fold, and 2.72-fold increased risk of 3-month, 2-year, and 5-year MACE, respectively. It is critical to identify a submaximal predictor during CPET for patients who survive AMI. Our findings suggested that OUES could be a significant prognostic indicator in patients after first AMI in both the short and long term.

Preoperative aerobic fitness and perioperative outcomes in patients undergoing cystectomy before and after implementation of a national lockdown

BackgroundLower fitness is a predictor of adverse outcomes after radical cystectomy. Lockdown measures during the COVID-19 pandemic affected daily physical activity. We hypothesised that lockdown during the pandemic was associated with a reduction in preoperative aerobic fitness and an increase in postoperative complications in patients undergoing radical cystectomy. MethodsWe reviewed routine preoperative cardiopulmonary exercise testing (CPET) data collected prior to the pandemic (September 2018 to March 2020) and after lockdown (March 2020 to July 2021) in patients undergoing radical cystectomy. Differences in CPET variables, Postoperative Morbidity Survey (POMS) data, and length of hospital stay were compared. ResultsWe identified 267 patients (85 pre-lockdown and 83 during lockdown) who underwent CPET and radical cystectomy. Patients undergoing radical cystectomy throughout lockdown had lower ventilatory anaerobic threshold (9.0 [7.9–10.9] vs 10.3 [9.1–12.3] ml kg−1 min−1; P=0.0002), peak oxygen uptake (15.5 [12.9–19.1] vs 17.5 [14.4–21.0] ml kg−1 min−1; P=0.015), and higher ventilatory equivalents for carbon dioxide (34.7 [31.4–38.5] vs 33.4 [30.5–36.5]; P=0.030) compared with pre-lockdown. Changes were more pronounced in males and those aged >65 yr. Patients undergoing radical cystectomy throughout lockdown had a higher proportion of day 5 POMS-defined morbidity (89% vs 75%, odds ratio [OR] 2.698, 95% confidence interval [CI] 1.143–6.653; P=0.019), specifically related to pulmonary complications (30% vs 13%, OR 2.900, 95% CI 1.368–6.194; P=0.007) and pain (27% vs 9%, OR 3.471, 95% CI 1.427–7.960; P=0.004), compared with pre-lockdown on univariate analysis. ConclusionsLockdown measures in response to the COVID-19 pandemic were associated with a reduction in fitness and an increase in postoperative morbidity among patients undergoing radical cystectomy.

Left atrial strain in patients after arterial switch operation for transposition of the great arteries

Background Left atrial (LA) strain, comprising LA reservoir, conduit and contractile function could add mechanistic information of patients after arterial switch operation (ASO) for transposition of the great arteries (TGA). ASO patients might have abnormal ventriculoarterial coupling, which makes them vulnerable to left ventricle (LV) dysfunction and results in reduced exercise capacity. This explorative study aimed to evaluate the relation between LA strain, atrial size, ventricular function, and exercise data obtained by cardiopulmonary exercise testing (CPET). Methods In a cohort of 44 patients (71% male, mean age 25 ± 4 years) LA strain was measured using transthoracic speckle-tracking echocardiography. Further assessment involved standard echocardiography, CPET evaluation, and blood sampling. LA strain values were compared to normal values. Correlations were calculated. Regression analysis with all strain variables to the CPET data was performed. Results LA reservoir, conduit and contractile strain were normal in 30%, 89% and 50% of the patients, respectively. LA reservoir/contractile strain correlated to LV ejection fraction (ρ 0.310/−0.159, respectively) and LA reservoir/conduit strain correlated to the LA volume index (ρ 0.336/−0.357, respectively). None of the individual LA strain parameters were associated with the CPET variables. In multivariate regression analysis, LA contractile strain was significantly associated with the percentage of predicted maximal heart rate (β − 2.555). Conclusions These data suggest that in TGA patients after ASO repair LA strain is impaired and correlates with LA size and LV function. However, impaired LA strain wasn’t associated with the standard CPET parameters. As such, clinical significance needs to be further unravelled.

A retrospective analysis of the association of effort-independent cardiopulmonary exercise test variables with postoperative complications in patients who underwent elective colorectal surgery

A retrospective analysis of the association of effort-independent cardiopulmonary exercise test variables with postoperative complications in patients who underwent elective colorectal surgery

Prognostic significance and pathophysiological insights of functional phenotypes clustering

Abstract Background Functional capacity (FC) is a marker of cardiorespiratory fitness reflecting the integrity of cardiac, respiratory and peripheral metabolic systems. Cardiopulmonary exercise test (CPET) is the method of reference to quantify the functional capacity through a multiparametric approach. Functional phenotypes can be identified according with the patterns of CPET variables. We sought to explore the prognostic role of CPET-derived functional phenotypes, identified by an automatic clustering process, and to understand the underlying cardiac pathophysiology as assessed by exercise-echocardiography (Exe-Echo). Methodology 1379 unselected subjects who underwent to CPET combined with Exe-Echo were included in the study. Cluster analysis based on CPET variables (% of predicted peakVO2, anaerobic threshold, VE/VCO2, peak respiratory ratio, chronotropic index, O2 pulse, peak PetCO2, VO2/WR slope and heart rate recovery) identified 4 clusters (C1= 207, C2= 546, C3= 475, C4= 151 subjects), differing primarily for a progressive worsening of FC (% of PeakVO2: 87±18, 75±13, 60±14, 48±13%; VE/VCO2 25.3±2.7, 26.5±3.0, 30.8±4.3, 39.4±7.8; in C1, C2, C3, C4 respectively, all p&amp;lt;.001). Rest and exercise parameters of Exe-Echo were used to define cardiac characteristics and presented in a standardized radar clustering (fig 1). Patients were tracked for the combined end-point of death + heart failure hospitalization. Results C1 presented normal cardiac morphology and function with expected increase of stroke volume (SV) and cardiac output (CO) during exercise, without significant valvular disease; C2 and C3 showed a mild-to-medarately abnormal rest and exercise echo parameters, characterized by LV progressive dilatation, mild systolic dysfunction, mitral regurgitation (MR) and increased systolic pulmonary pressure (SPAP); C4 corresponded to severe cardiac remodelling with LV and left atrial enlargement, severe MR, rest pulmonary hypertension and severely impaired contractile reserve (reduced exercise SV and CO). The 4 clusters were strongly associated with prognosis, as shown by KM of survival free from combined event (p&amp;lt;.0001; fig 2). Conclusions automatic clustering of CPET parameters identified 4 clusters strongly associated with hard end-points (mortality and HF hospitalization). Exe-Echo provided cluster-related pathophysiological insights explaining the mechanisms responsible for prognosis decline. This combined CPET-ExeEcho approach may help in identifying high risk patients and in defining new therapeutic targets.Radar chart of echo variablesKM of combined end-point (death+HF)

Serum magnesium and phosphorus values are lower among patients with paroxysmal atrial fibrillation: insights from the PLACEBO study

Abstract Background Magnesium and phosphorus comprise micronutrients in circulating blood, while associated disorders have been linked with increased risk of cardiovascular disease (CVD). Low serum magnesium has been connected to atrial fibrillation (AF) development among individuals without CVD, as patients with higher serum phosphorus levels, without chronic kidney disease (CKD), demonstrate an increased risk of AF plus higher rates of cardiovascular morbidity. Patients with paroxysmal atrial fibrillation (PAF) seem to hold the same cardiovascular risk as patients with permanent AF. The exact connection between serum magnesium and phosphorus levels and PAF has not been adequately explored. Purpose We aimed to investigate the potential relationship between serum magnesium and phosphorus levels and the number of AF paroxysms during the past 6 months from enrollment. Methods We analyzed preliminary data from the Ergospirometry in Paroxysmal Atrial Fibrillation Prognosis (PLACEBO) trial (NCT05246423), an observational, prospective, single-center cohort study aiming to examine the prognostic role of cardiopulmonary exercise testing variables in the future paroxysms of AF. We included 53 patients diagnosed with PAF, without CKD, and 30 healthy individuals. Normality was assessed with the Shapiro-Wilk test. Normally distributed variables are presented as mean±SD and significance was investigated with T-test while non-normally variables were distributed as median (IQR) and investigated with the Mann-Whitney U test. A p-value &amp;lt;0.05 was considered statistically significant. Results The study cohort comprised 54 patients with PAF, without CKD, and 30 healthy individuals. Baseline demographics are presented in the relevant table. Patients with PAF were older than controls and they had more comorbidities, as expected. Serum magnesium and phosphorus levels were significantly lower among patients with PAF compared to controls [1.9±0.22 versus 2.13±0.26 mg/dl and 3.95 (0.75) versus 3.3 (0.65) respectively (p&amp;gt;0.001)]. Higher serum phosphorus levels were associated with lowest frequency of AF paroxysms within the previous 6 months (R=-0.293, p=0.039). Conclusions Patients with PAF demonstrate lower serum magnesium and phosphorus levels compared to healthy individuals. This might be in part explained by the fact that serum phosphorus is known to be inversely associated with BMI; in our cohort, BMI was higher among patients with PAF. The lowest the frequency of AF episodes, the highest the serum phosphorus levels, a finding that comes in contrary with previous reports pointing towards an increased risk of AF development and higher cardiovascular mortality among individuals with higher serum phosphorus levels. Our findings may highlight novel potential therapeutic strategies targeting serum magnesium and phosphorus in patients with PAF, with an eye to minimize the number of AF paroxysms.Table

Lack of effect of an in-line filter on cardiopulmonary exercise testing variables in healthy subjects.

Pathogen transmission during cardio-pulmonary exercise testing (CPET) is caused by carrier aerosols generated during respiration. Ten healthy volunteers (age range: 34 ± 15; 4 females) were recruited to see if the physiological reactions to ramp-incremental CPET on a cycle ergometer were affected using an in-line filter placed between the mouthpiece and the flow sensor. The tests were in random order with or without an in-line bacterial/viral spirometer filter. The work rate aligned, time interpolated 10s bin data were compared throughout the exercise period. From rest to peak exercise, filter use increased only minute ventilation ([Formula: see text]E) (Δ[Formula: see text]E = 1.56 ± 0.70L/min, P < 0.001) and tidal volume (VT) (ΔVT = 0.10 ± 0.11L, P = 0.014). Over the entire test, the slope of the residuals for [Formula: see text]CO2 was positive (0.035 ± 0.041 (ΔL/L), P = 0.027). During a ramp-incremental CPET in healthy subjects, an in-line filter increased [Formula: see text]E and VT but not metabolic rate. In conclusion, using an in-line filter is feasible, does not affect appreciably the physiological variables, and may mitigate risk of aerosol dispersion during CPET.

Serial Changes in Cardiopulmonary Exercise Testing Parameters in Untreated Patients With Transthyretin Cardiac Amyloidosis

BackgroundTransthyretin amyloid cardiomyopathy (ATTR-CM) is associated with a progressive reduction of functional capacity. The progression of cardiopulmonary exercise testing (CPET) parameters over time is still unknown. MethodsIn this study, 55 patients with ATTR-CM underwent 2 serial cardiologic evaluations and CPETs in a national referral center for cardiac amyloidosis (Careggi University Hospital, Florence). ResultsForty-three patients (78%) had wild-type ATTR. Median age was 80 years (interquartile range [IQR] 76-83 years), and 50 of the patients (91%) were men. At baseline, median peak oxygen consumption (pVO2) was 15 mL/kg/min (IQR 12-18 mL/kg/min), percentage of predicted pVO2 (%ppVO2) was 71% (IQR 60%-83%) and VE/VCO2 slope was 31 (IQR 26-34). After a median follow-up of 14 months (IQR 13-16 months), pVO2, %ppVO2 and VE/VCO2 slope were significantly worsened (−1.29 mL/kg/min [95% confidence interval (CI): −1.85 to −0.74; P < 0.01], −4.5% [95% CI: −6.9 to −2.02; P < 0.01], and 8.6 [95% CI 6-11; P < 0.01], respectively). Furthermore, exercise time (−39 s, 95% CI: −59 to −19; P < 0.01), exercise tolerance (−0.47 metabolic equivalents, 95% CI: −0.69 to −0.2; P < 0.01), and peak systolic pressure (−10.8 mm Hg, 95% CI: −16.2 to −5.4; P < 0.01) were significantly reduced. The worsening in CPET variables did not correspond with a significant change in echocardiographic parameters. ConclusionsCardiorespiratory response to exercise significantly worsened over a short period of time in patients with ATTR-CM. Serial CPET may be useful to identify early disease progression.

326 Cardiopulmonary Exercise Test as Predictor of Postoperative Ileus in Elective Colorectal Surgery – a Prospective Cohort Study

Abstract Aim Postoperative ileus (POI) is a complication where there is abnormal pattern of slow or absent gastrointestinal motility after surgery. Elderly, frail, and comorbid patients often undergo cardiopulmonary exercise test (CPET) to determine their risks and suitability for major surgery. A literature review on Pubmed and Web of Science reveal no studies have been published on whether CPET variables can act as a predictor of POI. Hence, we aim to investigate whether there is a correlation between CPEX and post-operative ileus or major complications after colorectal surgery. Method All patients with stage I-IV Colorectal cancer who underwent CPET test between January 2013-June 2021 before elective major colorectal surgery were enrolled. Anaerobic threshold (AT) was used as a marker of cardiopulmonary fitness on CPET. POI was defined in any patient with NGT inserted postoperatively. Major complications were classified using Clavien-Dindo Classification≥Grade 3. Fisher’s exact test was used for categorical variables and independent sample t-test for continuous variables. Results In total, 115 patients were included - 64% were males and median age was 78(51-95) years old. Mean Anaerobic threshold was 10.4(6.4-15.6) mg/kg/min. Thirty-three(29%) and fifteen(13%) patients experienced POI and major complications respectively. There were no significant differences in mean AT for those who had POI versus without (10.9 vs 10.2, p = 0.13) and those with major complications versus without (10.7 vs 10.4, p = 0.62). Conclusions The overall incidence of POI was relatively high. Our study did not confirm level of cardiorespiratory fitness as a predictor of postoperative ileus or major complications.

Cardiopulmonary exercise testing criteria for advanced therapies in patients with heart failure.

Many cardiology associations endorse the role of the cardiopulmonary exercise test (CPET) to define the severity of impairment of functional capacity in individuals with heart failure with reduced ejection fraction (HFrEF) and when evaluating the need for advanced therapies for these patients. The focus of the CPET within the cardiology community has been on peak volume of oxygen uptake (VO2). However, several CPET variables are associated with outcomes in individuals with and without chronic disease and can inform clinical decisions in individuals with HFrEF. In this manuscript, we will review the normal cardiopulmonary response to a graded exercise test and review current guideline recommendations relative to CPET in patients with HFrEF.

Cardiopulmonary exercise testing before and after intravenous iron in preoperative patients: a prospective clinical study

BackgroundAnemia is associated with impaired physical performance and adverse perioperative outcomes. Iron-deficiency anemia is increasingly treated with intravenous iron before elective surgery. We explored the relationship between exercise capacity, anemia, and total hemoglobin mass (tHb-mass) and the response to intravenous iron in anemic patients prior to surgery.MethodsA prospective clinical study was undertaken in patients having routine cardiopulmonary exercise testing (CPET) with a hemoglobin concentration ([Hb]) < 130 g.l−1 and iron deficiency/depletion. Patients underwent CPET and tHb-mass measurements before and a minimum of 14 days after receiving intravenous (i.v.) Ferric derisomaltose (Monofer®) at the baseline visit. Comparative analysis of hematological and CPET variables was performed pre and post-iron treatment.ResultsTwenty-six subjects were recruited, of whom 6 withdrew prior to study completion. The remaining 20 (9 [45%] male; mean ± SD age 68 ± 10 years) were assessed 25 ± 7 days between baseline and the final visit. Following i.v. iron, increases were seen in [Hb] (mean ± SD) from 109 ± 14 to 116 ± 12 g l−1 (mean rise 6.4% or 7.3 g l−1, p =  < 0.0001, 95% CI 4.5–10.1); tHb-mass from 497 ± 134 to 546 ± 139 g (mean rise 9.3% or 49 g, p =  < 0.0001, 95% CI 29.4–69.2). Oxygen consumption at anerobic threshold (dot{text{V}} O2 AT) did not change (9.1 ± 1.7 to 9.8 ± 2.5 ml kg−1 min−1, p = 0.09, 95% CI − 0.13 − 1.3). Peak oxygen consumption (dot{text{V}} O2 peak) increased from 15.2 ± 4.1 to 16 ± 4.4 ml.kg.−1 min−1, p = 0.02, 95% CI 0.2–1.8) and peak work rate increased from 93 [67–112] watts to 96 [68–122] watts (p = 0.02, 95% CI 1.3–10.8).ConclusionPreoperative administration of intravenous iron to iron-deficient/deplete anemic patients is associated with increases in [Hb], tHb-mass, peak oxygen consumption, and peak work rate. Further appropriately powered prospective studies are required to ascertain whether improvements in tHb-mass and performance in turn lead to reductions in perioperative morbidity.Trial registrationClinicalTrials.gov identifier: NCT 033 46213.

End-tidal oxygen partial pressure is a strong prognostic predictive factor in patients with cardiac disease.

Cardiopulmonary exercise testing (CPET) variables represent central and peripheral factors and combined factors in the pathology of patients with cardiac disease. The difference in end-tidal oxygen partial pressure from resting to anaerobic threshold (ΔPETO2 ) may represent predominantly peripheral factors. This study aimed to verify the prognostic significance of ΔPETO2 for major adverse cardiac and cerebrovascular events (MACCE) in cardiac patients, including comparison with the minute ventilation-carbon dioxide production relationship (VE/VCO2 slope), and peak oxygen uptake (VO2 ). In total, 185 patients with cardiac disease who underwent CPET were consecutively enroled in this retrospective study. The primary endpoint was 3-year MACCE. The ability of ΔPETO2 , VE/VCO2 slope, and peak VO2 to predict MACCE was examined. Optimal cut-off values for predicting MACCE were 2.0 mmHg for ΔPETO2 (area under the curve [AUC]: 0.829), 29.8 for VE/VCO2 slope (AUC: 0.734), and 19.0 mL/min/kg for peak VO2 (AUC: 0.755). The AUC of ΔPETO2 was higher than those of VE/VCO2 slope and peak VO2 . The MACCE-free survival rate was significantly lower in the ΔPETO2  ≤ 2.0 group versus the ΔPETO2  > 2.0 group (44.4% vs. 91.2%, p < 0.001). ΔPETO2  ≤ 2.0 was an independent predictor of MACCE after adjustment for age and VE/VCO2 slope (hazard ratio [HR], 7.28; p < 0.001) and after adjustment for age and peak VO2 (HR, 6.52; p < 0.001). ΔPETO2 was a strong predictor of MACCE independent of and superior to VE/VCO2 slope and peak VO2 in patients with cardiac disease.

#5045 CARDIORESPIRATORY FITNESS IN KIDNEY TRANSPLANT RECIPIENTS: A CASE-CONTROL STUDY AND INITIAL REVIEW OF THE EFFECTS OF A HOME-BASED EXERCISE PROGRAMME

Abstract Background and Aims Kidney transplant recipients (KTRs) have an increased burden of cardiovascular disease (CVD) due to clustering of traditional and non-traditional risk factors. Poor cardiorespiratory fitness (CRF) is linked to higher levels of morbidity and mortality. Cardiorespiratory fitness is a significant predictor of 7-year risk of mortality, with each 1 ml/kg/min increase in VO2 associated with a 1% decrease in risk of mortality.[1] Although KTRs have higher CRF than patients with kidney failure, performance compared to the general population has not been quantified. Neither has the link between CRF and physical function. We assessed differences in CRF between KTRs and healthy volunteers in a case-control study. We then explored relationships between CRF and physical function and possible effects of a 12-week structured home-based exercise programme in KTRs. Method Case-control: 20 KTRs (10 male; age 61.2 ±8.1 years; body mass 84.1 ±19.9 kg) and 20 healthy volunteers (10 male; age 61.9 ±7.7 years; body mass 76.7 ±18.1 kg) completed a continuous ramp cardiopulmonary exercise test (CPET) to volitional exhaustion on a cycle ergometer. CPET variables were compared between groups using independent samples t-tests. Thirteen KTRs (6 male; age 47.8 ±15.9 years; eGFR 64.6 ±19.1 ml/min/1.73 m2), to date, have completed a 12-week structured, combined aerobic and resistance, home-based exercise programme as part of a pilot randomised controlled trial.[2] Bivariate correlations were used to explore the association between cardiorespiratory fitness and physical function measures (sit-to-stand 60 [STS60], timed up and go [TUAG], gait speed [GS] and handgrip strength [HGS]). Paired samples t-tests were used to compare pre- and post-intervention variables. Results Case-control: Cardiorespiratory fitness (VO2 peak) was lower in KTRs (18.4±5.2 mL/kg/min) than in healthy volunteers (24.3 ±5.9 mL/kg/min), a difference of 5.9 mL/kg/min (95% CI, 2.4-9.5), t(38) = 3.35, p &amp;lt;.001. Peak heart rate achieved was higher in healthy volunteers than in KTRs (154 v 136 bpm; p = .009). Maximum power achieved was higher in healthy volunteers but did not reach significance (147 v 116 W; p = .052). There was a positive correlation between STS60 and VO2 peak (r = .652, p = .016) and between GS and VO2 peak (r = .583, p = .037). There was a negative correlation between TUAG and VO2 peak (r = .-.664, p = .013) and no association between HGS and VO2 peak. There was an increase in VO2 peak after the 12-week exercise programme (19.4±4.5 mL/kg/min to 20.4±5.0 mL/kg/min, p = .018). Maximum power achieved did not change post-intervention (118 v 121 W; p = .423). STS60 was the only physical function test to improve post-intervention (24 v 27; p = .010). Conclusion Cardiorespiratory fitness in KTRs is significantly impaired compared to healthy control subjects. In KTRs, aerobic fitness assessed with VO2 peak correlated with field tests assessing physical function. Initial findings suggest that CRF may improve following a structured, home-based programme of exercise, but these data need confirming in larger studies and will be assessed in the final analysis of this pilot randomised trial.

Cardiorespiratory fitness assessed with cardiopulmonary exercise testing in patients with juvenile idiopathic arthritis: a systematic review and meta-analysis.

Juvenile idiopathic arthritis (JIA) is the most common type of arthritis in children and adolescents, causing joint damage, chronic pain and disability. Deconditioning is also prevalent in patients with JIA due to both inactivity and the disease progression, resulting in reduced cardiorespiratory fitness (CRF). We aimed to evaluate CRF of patients with JIA compared to healthy controls. This is a systematic review and meta-analysis of studies using cardiopulmonary-exercise-testing (CPET) to examine differences in determinants of CRF between patients with JIA versus healthy controls. The primary outcome was peak oxygen uptake (VO2peak). Literature search involved PubMed, Web of Science and Scopus databases, manual search of article references and grey literature. Quality assessment was undertaken with Newcastle-Ottawa-Scale. From 480 literature records initially retrieved, 8 studies (538 participants) were included in final meta-analysis. VO2peak was significantly lower in patients with JIA compared to controls [weighted-mean-difference, WMD:-5.95 ml/kg/min, 95% CI (-9.26; -2.65)]; Exercise duration as well as VO2peak(%predicted) were found to be significantly impaired in patients with JIA compared to controls [standardized-mean-difference, SMD: -0.67, 95% CI (-1.04; -0.29)] and [WMD: -11.31%, 95% CI (-20.09; -2.53)], respectively, while no significant differences were found in maximum heart rate. VO2peak and other CPET variables were lower in patients with JIA compared to controls, indicating reduced CRF in the former. Overall, exercise programs for patients with JIA should be promoted as part of their treatment to improve physical fitness and reduce muscle atrophy. CRD42022380833.

Exercise Pathophysiology and Testing in Individuals With a Fontan Circulation.

The Fontan circulation, a surgical palliation for single-ventricle congenital heart disease, profoundly impacts the cardiopulmonary response to exercise. Reliant on passive pulmonary blood flow, the Fontan circulation has limited capacity to augment cardiac output as necessary to supply working muscles during exercise. Cardiopulmonary exercise testing (CPET) objectively assesses cardiorespiratory fitness and provides insight into the etiology of exercise intolerance. Furthermore, CPET variables, such as peak oxygen consumption and submaximal variables, have prognostic value and may be used as meaningful endpoints in research studies. CPET is also useful in clinical research applications to assess the effect of pharmacologic or other interventions. Medical therapies to improve exercise tolerance in individuals with a Fontan circulation, such as pulmonary vasodilators, may modestly improve peak oxygen consumption. Exercise training focused on aerobic fitness and lower extremity strength may have a more consistent and larger impact on these measures of aerobic fitness. CPET is a valuable diagnostic and prognostic tool for those with a Fontan circulation. Newer ancillary assessments, such as noninvasive peripheral venous pressure monitoring and cardiac output measurements, hold promise to provide a more nuanced insight into the underlying pathophysiology.

Cardiopulmonary exercise testing predicts prognosis in amyloid cardiomyopathy: a systematic review and meta-analysis.

The clinical value of cardiopulmonary exercise testing (CPET) in cardiac amyloidosis (CA) is uncertain. Due to the growing prevalence of the disease and the current availability of disease-modifying drugs, prognostic stratification is becoming fundamental to optimizing the cost-effectiveness of treatment, patient phenotyping, follow-up, and management. Peak VO2 and VE/VCO2 slope are currently the most studied CPET variables in clinical settings, and both demonstrate substantial, independent prognostic value in several cardiovascular diseases. We aim to study the association of peak VO2 and VE/VCO2 slope with prognosis in patients with CA. We performed a systematic review and searched for clinical studies performing CPET for prognostication in patients with transthyretin-CA and light-chain-CA. Studies reporting hazard ratio (HR) for mortality and peak VO2 or VE/VCO2 slope were further selected for quantitative analysis. HRs were pooled using a random-effect model. Five studies were selected for qualitative and three for quantitative analysis. A total of 233 patients were included in the meta-analysis. Mean peak VO2 resulted consistently depressed, and VE/VCO2 slope was increased. Our pooled analysis showed peak VO2 (pooled HR 0.89, 95% CI 0.84-0.94) and VE/VCO2 slope (pooled HR 1.04, 95% CI 1.01-1.07) were significantly associated with the risk of death in CA patients, with no significant statistical heterogeneity for both analyses. CPET is a valuable tool for prognostic stratification in CA, identifying patients at increased risk of death. Large prospective clinical trials are needed to confirm this exploratory finding.

Increased Dead Space Ventilation as a Contributing Factor to Persistent Exercise Limitation in Patients with a Left Ventricular Assist Device.

(1) Background: The exercise capacity of patients with a left ventricular assist device (LVAD) remains limited despite mechanical support. Higher dead space ventilation (VD/VT) may be a surrogate for right ventricular to pulmonary artery uncoupling (RV-PA) during cardiopulmonary exercise testing (CPET) to explain persistent exercise limitations. (2) Methods: We investigated 197 patients with heart failure and reduced ejection fraction with (n = 89) and without (HFrEF, n = 108) LVAD. As a primary outcome NTproBNP, CPET, and echocardiographic variables were analyzed for their potential to discriminate between HFrEF and LVAD. As a secondary outcome CPET variables were evaluated for a composite of hospitalization due to worsening heart failure and overall mortality over 22 months. (3) Results: NTproBNP (OR 0.6315, 0.5037-0.7647) and RV function (OR 0.45, 0.34-0.56) discriminated between LVAD and HFrEF. The rise of endtidal CO2 (OR 4.25, 1.31-15.81) and VD/VT (OR 1.23, 1.10-1.40) were higher in LVAD patients. Group (OR 2.01, 1.07-3.85), VE/VCO2 (OR 1.04, 1.00-1.08), and ventilatory power (OR 0.74, 0.55-0.98) were best associated with rehospitalization and mortality. (4) Conclusions: LVAD patients displayed higher VD/VT compared to HFrEF. Higher VD/VT as a surrogate for RV-PA uncoupling could be another marker of persistent exercise limitations in LVAD patients.

Are you short of breath? comparing functional capacity using new york heart association class and cardiopulmonary exercise testing

Abstract Funding Acknowledgements Type of funding sources: None. Background New York Heart Association (NYHA) scale is used to assess symptom severity in heart failure patients. Despite it being used routinely in clinical practice, it is heavily dependent on patient and physician subjectivity. Cardiopulmonary exercise testing (CPET) provides a potentially more objective and reproducible measure of functional capacity. Purpose To assess functional capacity in NYHA 1 versus NYHA 2-4 patients. Investigators also wanted to explore any relationship between NYHA class and CPET variables in heart failure patients. Method A retrospective analysis of patients who underwent CPET between 2021 &amp; 2022 was performed. The patients were grouped according to NYHA score and ejection fraction (EF). A separate subgroup analysis was carried out in NYHA 1, comparing patients with an EF &amp;lt; 35% and EF &amp;gt; 35%. Results A total of 160 patients were included, a dominant male (81.3%) Caucasian (95%) population with an average age of 53.9 years. 13.8% had an EF &amp;lt;35%. 51.9% had ischaemic cardiomyopathy. 103 (64.4%) patients had a NYHA score of 1, the rest had a NYHA score of 2-3. There was no significant difference between demographic parameters and co-morbidities between the groups. Figure 1 depicts CPET parameters comparing NYHA 1 vs NYHA 2-4 groups. VO2 MAX and % VO2 Max Predicted were significantly higher in NYHA 1 vs NYHA 2-4 (Figure 1). NT-proBNP levels were lower in the NYHA 1 group (378 pg/mL vs 850 pg/mL, p=0.023). Further analysis of the NYHA Class 1 group, comparing EF&amp;lt; 35% and &amp;gt;35% was carried out. It was discovered that despite being assigned the same NYHA Class, the EF &amp;lt;35% group had significantly lower VO2 max, % predicted VO2 max and VE/VCO2. EF was an important predictor of CPET performance in NYHA 1 patients. Those with an EF &amp;lt;35% had a lower VO2 max (p=0.001), low % VO2 Max predicted (p=0.005) and higher VE/VCO2 (p=0.002). NT-proBNP was also higher in this subgroup (p=0.047). Conclusion NYHA is an effective tool at assessing symptom severity in heart failure patients, albeit subjectively. CPET is particularly useful in NYHA 1 patients as it can give an objective assessment of functional capacity in these asymptomatic individuals. Future studies should explore the possible role of CPET in determining suitability for advanced heart failure therapies in NYHA 1 heart failure patients.