Meziab O; Department of Pediatrics (Cardiology), University of Arizona,  Tucson, AZ, 85724, USA.
Dereszkiewicz E; Guerrero CE; Hoyer AW; Barber BJ; Klewer SE; Seckeler M;

Pediatric cardiology [Pediatr Cardiol] 2024 May 09.
Date of Electronic Publication: 2024 May 09.

Patients with Fontan physiology have reduced exercise performance compared to their peers as well as a higher incidence of bundle branch block (BBB). This study aims to investigate the association between BBB and exercise performance in the Fontan population through a retrospective review of the Pediatric Heart Network Fontan study public use dataset. “Low Performers” were defined as ≤ 25th percentile (for Fontan patients) for each exercise parameter at anaerobic threshold (AT) for gender and age and “Normal Performers” were all other patients. A total of 303 patients with Fontan physiology who underwent exercise testing reached AT and had complete data for BBB. BBB occurred more frequently in Low Performers for VO ₂ [OR (95% CI): 2.6 (1.4, 4.8)] and Work [OR (95% CI): 2.7 (1.4, 5.1)], suggesting that BBB in the Fontan population is associated with reduced exercise performance. This data adds to the existing clinical evidence of the adverse effects of conduction abnormalities on single ventricle cardiac output and adds support for consideration of cardiac resynchronization and multi-site ventricular pacing in this patient population.

(© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Wang AP; Division of Pediatric Cardiology, Ann & Robert H. Lurie Children’s Hospital of Chicago, Chicago, IL, USA.
Ward K; Griffith G; Gambetta K;

Pediatric transplantation [Pediatr Transplant] 2024 Jun; Vol. 28 (4), pp. e14772.

Background: Obesity and impaired exercise tolerance following heart transplantation increase the risk of post-transplant morbidity and mortality. The aim of this study was to evaluate the effect of body mass index on markers of exercise capacity in pediatric heart transplant recipients and compare this effect with a healthy pediatric cohort.
Methods: A retrospective analysis of cardiopulmonary exercise test data between 2004 and 2022 was performed. All patients exercised on a treadmill using the Bruce protocol. Inclusion criteria included patients aged 6-21 years, history of heart transplantation (transplant cohort) or no cardiac diagnosis (control cohort) at the time of testing, and a maximal effort test. Patients were further stratified within these two cohorts as underweight, normal, overweight, and obese based on body mass index groups. Two-way analyses of variance were performed with diagnosis and body mass index category as the independent variables.
Results: A total of 250 exercise tests following heart transplant and 1963 exercise tests of healthy patients were included. Heart transplant patients across all body mass index groups had higher resting heart rate and lower maximal heart rate, heart rate recovery at 1 min, exercise duration, and peak aerobic capacity (VO _2peak ). Heart transplant patients in the normal and overweight body mass index categories had higher VO _2peak and exercise duration when compared to underweight and obese patients.
Conclusion: Underweight status and obesity are strongly associated with lower VO _2peak and exercise duration in heart transplant patients. Normal and overweight heart transplant patients had the best markers of exercise capacity.

Kristenson, K; Linköping University, Sweden
Hedman, K;

J Thorac Cardiovasc Surg 2024 Mar 5:S0022-5223(24)00187-9.
doi: 10.1016/j.jtcvs.2024.02.021. Online ahead of print.

Geng L; Department of Cardiology, East Hospital, Tongji University, Shanghai 200120, China.
Huang S; Zhang T; Wang L; Zhou J; Gao L; Wang Y; Li J; Guo W; Li Y; Zhang Q;

International journal of cardiology. Heart & vasculature [Int J Cardiol Heart Vasc] 2024 Apr 13; Vol. 52, pp. 101409.
Date of Electronic Publication: 2024 Apr 13 (Print Publication: 2024).

Background: The role of cardiopulmonary exercise testing (CPET) parameters in evaluating the functional severity of coronary disease remains unclear. The aim of this study was to quantify the O ₂ -pulse morphology and investigate its relevance in predicting the functional severity of coronary stenosis, using Murray law-based quantitative flow ratio (μQFR) as the reference.
Methods: CPET and μQFR were analyzed in 138 patients with stable coronary artery disease (CAD). The O ₂ -pulse morphology was quantified through calculating the O ₂ -pulse slope ratio. The presence of O ₂ -pulse plateau was defined according to the best cutoff value of O ₂ -pulse slope ratio for predicting μQFR ≤ 0.8.
Results: The optimal cutoff value of O ₂ -pulse slope ratio for predicting μQFR ≤ 0.8 was 0.4, with area under the curve (AUC) of 0.632 (95 % CI: 0.505-0.759, p =  0.032). The total discordance rate between O ₂ -pulse slope ratio and μQFR was 27.5 %, with 13 patients (9.4 %) being classified as mismatch (O ₂ -pulse slope ratio > 0.4 and μQFR ≤ 0.8) and 25 patients being classified as reverse-mismatch (O ₂ -pulse slope ratio ≤ 0.4 and μQFR > 0.8). Angiography-derived microvascular resistance was independently associated with mismatch (OR 0.07; 95 % CI: 0.01-0.38, p =  0.002) and reverse-mismatch (OR 9.76; 95 % CI: 1.47-64.82, p =  0.018).
Conclusion: Our findings demonstrate the potential of the CPET-derived O ₂ -pulse slope ratio for assessing myocardial ischemia in stable CAD patients

Farah CS; Faculty of Medicine and Health The University of Sydney Sydney New South Wales Australia.
Seccombe LM; King GG; Chapman DG; Irvin CG;

Respirology case reports [Respirol Case Rep] 2024 Apr 26; Vol. 12 (5), pp. e01360.
Date of Electronic Publication: 2024 Apr 26 (Print Publication: 2024).

A 64-year-old obese gentleman attended for further evaluation of ongoing dyspnoea in the context of a previous diagnosis of moderate COPD treated with dual long-acting bronchodilators. A cardiopulmonary exercise test (CPET) was performed, which demonstrated reduced peak work and oxygen consumption with evidence of dynamic hyperinflation, abnormal gas exchange and ventilatory limitation despite cardiac reserve. The CPET clarified the physiological process underpinning the patient’s dyspnoea and limiting the patient’s activities. This, in turn, helped the clinician tailor the patient’s management plan.

Panassollo TRB; School of Clinical Sciences, Auckland, New Zealand.
Lord S; Rashid U; Taylor D; Mawston G;

European journal of applied physiology [Eur J Appl Physiol] 2024 Apr 29.
Date of Electronic Publication: 2024 Apr 29.

Purpose: Heart rate (HR) response is likely to vary in people with Parkinson’s disease (PD), particularly for those with chronotropic incompetence (CI). This study explores the impact of CI on HR and metabolic responses during cardiopulmonary exercise test (CPET) in people with PD, and its implications for exercise intensity prescription.
Methods: Twenty-eight participants with mild PD and seventeen healthy controls underwent CPET to identify the presence or absence of CI. HR and metabolic responses were measured at submaximal (first (VT1) and second (VT2) ventilatory thresholds), and at peak exercise. Main outcome measures were HR, oxygen consumption (VO ₂ ), and changes in HR responses (HR/WR slope) to an increase in exercise demand.
Results: CI was present in 13 (46%) PD participants (PDCI), who during CPET, exhibited blunted HR responses compared to controls and PD non-CI beyond 60% of maximal workload (p ≤ 0.05). PDCI presented a significantly lower HR at VT2, and peak exercise compared to PD non-CI and controls (p ≤ 0.001). VO ₂ was significantly lower in PDCI than PD non-CI and controls at VT2 (p = 0.003 and p = 0.036, respectively) and at peak exercise (p = 0.001 and p = 0.023, respectively).
Conclusion: Although poorly understood, the presence of CI in PD and its effect on HR and metabolic responses during incremental exercise is significant and important to consider when programming aerobic exercises.

Kunutsor SK; Diabetes Research Centre,  Leicester, UK. & Korea & Finland
Jae SY; Kurl S; Laukkanen JA;

No abstract available

Scandinavian cardiovascular journal : SCJ [Scand Cardiovasc J] 2024 Dec; Vol. 58 (1), pp. 2347289.
Date of Electronic Publication: 2024 Apr 29.

Stephan H; Department of Sports Medicine, University of Wuppertal, Moritzstraße 14, 42117 Wuppertal, Germany.
Klophaus N; Wehmeier UF; Tomschi F; Hilberg T;

Journal of clinical medicine [J Clin Med] 2024 Apr 12; Vol. 13 (8).
Date of Electronic Publication: 2024 Apr 12.

Background : Cardiopulmonary exercise testing is not used routinely. The goal of this study was to determine whether accurate estimates of VO ₂ values can be made at the beginning and at the end of a rehabilitation program.
Methods : A total of 91 cardiac rehabilitation patients were included. Each participant had to complete cardiopulmonary exercise testing at the beginning and at the end of a rehabilitation program. Measured VO ₂ values were compared with estimates based on three different equations.
Results : Analyses of the means of the differences in the peak values showed very good agreement between the results obtained with the FRIEND equation or those obtained with a combination of rules of thumb and the results of the measurements. This agreement was confirmed with the ICCs and with the standard errors of the measurements. The ACSM equation performed worse. The same tendency was seen when considering the VO ₂ values at percentage-derived work rates.
Conclusions : The FRIEND equation and the more easily applicable combination of rules of thumb are suitable for estimating the peak VO ₂ and the VO ₂ at a percentage-derived work rate in cardiac patients both at the beginning and at the end of a cardiac rehabilitation program.

Geng L; Department of Cardiology, East Hospital, Tongji University, Shanghai 200120, China.
Huang S; Zhang T; Wang L; Zhou J; Gao L; Wang Y; Li J; Guo W; Li Y; Zhang Q;

International journal of cardiology. Heart & vasculature [Int J Cardiol Heart Vasc] 2024 Apr 13; Vol. 52, pp. 101409.
Date of Electronic Publication: 2024 Apr 13 (Print Publication: 2024).

Background: The role of cardiopulmonary exercise testing (CPET) parameters in evaluating the functional severity of coronary disease remains unclear. The aim of this study was to quantify the O ₂ -pulse morphology and investigate its relevance in predicting the functional severity of coronary stenosis, using Murray law-based quantitative flow ratio (μQFR) as the reference.
Methods: CPET and μQFR were analyzed in 138 patients with stable coronary artery disease (CAD). The O ₂ -pulse morphology was quantified through calculating the O ₂ -pulse slope ratio. The presence of O ₂ -pulse plateau was defined according to the best cutoff value of O ₂ -pulse slope ratio for predicting μQFR ≤ 0.8.
Results: The optimal cutoff value of O ₂ -pulse slope ratio for predicting μQFR ≤ 0.8 was 0.4, with area under the curve (AUC) of 0.632 (95 % CI: 0.505-0.759, p =  0.032). The total discordance rate between O ₂ -pulse slope ratio and μQFR was 27.5 %, with 13 patients (9.4 %) being classified as mismatch (O ₂ -pulse slope ratio > 0.4 and μQFR ≤ 0.8) and 25 patients being classified as reverse-mismatch (O ₂ -pulse slope ratio ≤ 0.4 and μQFR > 0.8). Angiography-derived microvascular resistance was independently associated with mismatch (OR 0.07; 95 % CI: 0.01-0.38, p =  0.002) and reverse-mismatch (OR 9.76; 95 % CI: 1.47-64.82, p =  0.018).
Conclusion: Our findings demonstrate the potential of the CPET-derived O ₂ -pulse slope ratio for assessing myocardial ischemia in stable CAD patients

Pigakis KM; Various centres in, Greece.;
Stavrou VT; Kontopodi AK; Pantazopoulos I; Daniil Z; Larissa, Greece.; DeparGourgoulianis K;

Sports (Basel, Switzerland) [Sports (Basel)] 2024 Apr 19; Vol. 12 (4).
Date of Electronic Publication: 2024 Apr 19.

Background: Professional cycling puts significant demands on the respiratory system. Exercise-induced bronchoconstriction (EIB) is a common problem in professional athletes. Small airways may be affected in isolation or in combination with a reduction in forced expiratory volume at the first second (FEV ₁ ). This study aimed to investigate isolated exercise-induced small airway dysfunction (SAD) in professional cyclists and assess the impact of this phenomenon on exercise capacity in this population.
Materials and Methods: This research was conducted on professional cyclists with no history of asthma or atopy. Anthropometric characteristics were recorded, the training age was determined, and spirometry and specific markers, such as fractional exhaled nitric oxide (FeNO) and immunoglobulin E (IgE), were measured for all participants. All of the cyclists underwent cardiopulmonary exercise testing (CPET) followed by spirometry.
Results: Compared with the controls, 1-FEV ₃ /FVC (the fraction of the FVC that was not expired during the first 3 s of the FVC) was greater in athletes with EIB, but also in those with isolated exercise-induced SAD. The exercise capacity was lower in cyclists with isolated exercise-induced SAD than in the controls, but was similar to that in cyclists with EIB. This phenomenon appeared to be associated with a worse ventilatory reserve (VE/MVV%).
Conclusions: According to our data, it appears that professional cyclists may experience no beneficial impacts on their respiratory system. Strenuous endurance exercise can induce airway injury, which is followed by a restorative process. The repeated cycle of injury and repair can trigger the release of pro-inflammatory mediators, the disruption of the airway epithelial barrier, and plasma exudation, which gradually give rise to airway hyper-responsiveness, exercise-induced bronchoconstriction, intrabronchial inflammation, peribronchial fibrosis, and respiratory symptoms. The small airways may be affected in isolation or in combination with a reduction in FEV ₁ . Cyclists with isolated exercise-induced SAD had lower exercise capacity than those in the control group.