Martin Talavera M;Manso B; Seville, Spain.Cejudo Ramos P; Rodriguez Puras MJ; Wals Rodriguez AJ;
Garcia de Vinuesa PG;

Cardiology in the young [Cardiol Young] 2021 Oct 04, pp. 1-4. Date of Electronic Publication: 2021 Oct 04.

Introduction: Cardiopulmonary exercise test (CPET) allows quantification of functional capacity of patients with Fontan. The objective of this study was to determine the role of CPET parameters in predicting a higher maximum oxygen consumption (VO2 max) and to analyse the role of CPET parameters in predicting an unfavourable outcome.
Methods: A retrospective, cross-sectional, descriptive study was carried out on 57 patients with Fontan, who had undergone incremental CPET with cycloergometer between 2010 and 2020. Determinants of VO2 max and determinants of clinical deterioration were analysed.
Results: In the univariate analysis, the variables significantly related to VO2 max were: age, sex, body mass index (BMI), years of Fontan evolution, intracardiac Fontan, oxygen consumption at anaerobic threshold (VO2AT), CO2 equivalents at anaerobic threshold (VE/VCO2) and chronotropic insufficiency. The multiple linear regression model that best fitted the relationship between VO2 max and independent variables (correlation coefficient 0.73) included sex (correlation index 3.35; p = 0.02), BMI (-0.27; p = 0.02), chronotropic failure (-2.79; p = 0.01) and VO2AT (0.92; p < 0.0001). In the univariate analysis of the prognostic CPET variables related to an unfavourable clinical situation, significance was only obtained with chronotropic insufficiency (p = 0.003). In multivariate analysis, chronotropic insufficiency maintains its association [p= 0.017, OR = 4.65 (1.3-16.5)].
Conclusions: In conclusion, together with the anthropometric parameters universally related to VO2 max, chronotropic insufficiency and VO2AT are the main determinants of functional capacity in patients with Fontan. Moreover, chronotropic insufficiency is closely related to unfavourable clinical evolution. Our data would support the intensive treatment of chronotropic insufficiency in order to improve the quality of life and the clinical situation of patients with Fontan.

Berkel AEM; van Dijk DPJ; Prins SN; van Meeteren NLU; Olde Damink SWM; Klaase JM; Bongers BC;

Colorectal disease : the official journal of the Association of Coloproctology of Great Britain and Ireland
[Colorectal Dis] 2021 Oct 06. Date of Electronic Publication: 2021 Oct 06.

Aim: Though cardiopulmonary exercise testing (CPET) is considered the gold standard, the preoperative abdominal computed tomography (CT) scan might also provide information concerning preoperative aerobic fitness for risk assessment. This study aimed to investigate the association between preoperative CT-scan derived body composition variables and preoperative CPET variables of aerobic fitness in colorectal surgery.
Method: In this retrospective cohort study, CT-images at level L3 were analysed for skeletal muscle mass, skeletal muscle radiation attenuation, visceral adipose tissue (VAT) mass, and subcutaneous adipose tissue mass. Regression analyses were performed to investigate the relation between CT-scan derived body composition variables, CPET-derived aerobic fitness, and other preoperative patient-related variables. Logistic regression analysis was performed to predict a preoperative anaerobic threshold (AT) ≤11.1 mL/kg/min as cut-off for having a high risk for postoperative complications.
Results: Data from 78 patients (45 males, mean (SD) age 74.5 (6.4) years) were analysed. A correlation coefficient of 0.55 was observed between absolute AT and skeletal muscle mass index. Absolute AT (R ² of 51.1%) was lower in patients with a lower skeletal muscle mass index, together with higher age, lower body mass, and higher American Society of Anesthesiologists (ASA) score. Higher ASA score (odds ratio 5.64; P=0.033) and higher VAT mass (odds ratio 1.02; P=0.036) were associated with an increased risk of an AT ≤11.1 mL/kg/min.
Conclusion: Body composition variables from the preoperative CT-scan were moderately associated with preoperative CPET-derived aerobic fitness. Higher ASA score and higher VAT mass were associated with an increased risk of an AT ≤11.1 mL/kg/min.

Smarz K;Jaxa-Chamiec T; Zaborska B; Tysarowski M; Budaj A;

Journal of clinical medicine [J Clin Med] 2021 Sep 09; Vol. 10 (18). Date of Electronic Publication: 2021 Sep 09.

Cardiac rehabilitation (CR) is indicated in all patients after acute myocardial infarction (AMI) to improve prognosis and exercise capacity (EC). Previous studies reported that up to a third of patients did not improve their EC after CR (non-responders). Our aim was to assess the cardiac and peripheral mechanisms of EC improvement after CR using combined exercise echocardiography and cardiopulmonary exercise testing (CPET-SE). The responders included patients with an improved EC assessed as a rise in peak oxygen uptake (VO ₂ ) ≥ 1 mL/kg/min. Peripheral oxygen extraction was calculated as arteriovenous oxygen difference (A-VO ₂ Diff). Out of 41 patients (67% male, mean age 57.5 ± 10 years) after AMI with left ventricular ejection fraction (LVEF) ≥ 40%, 73% improved their EC. In responders, peak VO ₂ improved by 27% from 17.9 ± 5.2 mL/kg/min to 22.7 ± 5.1 mL/kg/min, p < 0.001, while non-responders had a non-significant 5% decrease in peak VO ₂ . In the responder group, the peak exercise heart rate, early diastolic myocardial velocity at peak exercise, LVEF at rest and at peak exercise, and A-VO ₂ Diff at peak exercise increased, the minute ventilation to carbon dioxide production slope decreased, but the stroke volume and cardiac index were unchanged after CR. Non-responders had no changes in assessed parameters. EC improvement after CR of patients with preserved LVEF after AMI is associated with an increased heart rate response and better peripheral oxygen extraction during exercise.

Wang K; Jiang H; Zhang T; Yin L; Chen X; Luo J;

Frontiers in physiology [Front Physiol] 2021 Sep 10; Vol. 12, pp. 683942.
Date of Electronic Publication: 2021 Sep 10 (Print Publication: 2021).

Background: Maximum oxygen uptake (VO _2max ) is an important respiratory physiological index of the aerobic endurance of the body, especially for special groups such as drug addicts, and it is an important indicator for assessing the cardiopulmonary function and formulating exercise prescriptions. Although the cardiopulmonary exercise test (CPX) is a classic method to directly measure VO _2max , this method is limited by factors such as cumbersome operating procedures and expensive equipment, resulting in its relatively low applicability. Recently, many studies have begun to focus on the estimation of VO _2max in different groups of people, but few studies have focused on drug addicts.
Methods: Fifteen chemically synthesized drug addicts (such as amphetamines) and Fifteen plant-derived drug addicts (such as heroin) were recruited at the Chongqing Compulsory Isolation and Drug Rehabilitation Center in China. First, the VO _2max of subjects was directly measured through the CPX. Second, after subjects were fully rested, they were required to complete the 30-s high-leg raise, 1,000-m walk, and 3-min step experiment. Finally, SPSS 21.0 software was used to perform the correlation and linear regression analysis to verify the estimated effectiveness.
Results: (1) Regardless of chemically synthesized or natural plant-derived drug addicts, the years of drug use and walking time of 1,000 m were significantly negatively correlated with VO _2max (chemically synthesized: P < 0.01 and natural plant-derived: P < 0.05), the number of 30-s high-leg raises was a significantly positive correlation with VO _2max ( P < 0.05 and P < 0.01), and the 3-min step index was significantly positively correlated with VO _2max ( P < 0.01 and P < 0.01). (2) Regression analysis shows that the 30-s high-leg lift, 1,000-m walking, and 3-min step experiment could effectively estimate the VO _2max of chemically synthesized and natural plant-derived drug addicts. (3) Multiple linear regression constructed by the years of drug use combined with the step index has the highest estimated accuracy for the VO _2max of chemically synthesized drug addicts (96.48%), while the unary regression equation established by a single step index has the highest prediction accuracy for the VO _2max of natural plant-derived addicts (94.30%).
Conclusion: The indirect measurement method could effectively estimate the VO _2max of drug addicts, but different measurement methods have certain differences in the estimation accuracy of VO _2max of different drug addicts. In the future, the physical characteristics of drug users can be fully considered, combined with more cutting-edge science and technology, to make the estimation accuracy of VO _2max closer to the real level.

Crisafulli E; Dorelli G; Sartori G; Dalle Carbonare L;

International journal of cardiology [Int J Cardiol] 2021 Sep 17. Date of Electronic Publication: 2021 Sep 17.

NO ABSTRACT AVAILABLE

Oleksak F; Spakova B; Durdikova A; Durdik P; Kralova T; Igaz M; Molnar M;Gura M; Murgas D;

Respiratory physiology & neurobiology [Respir Physiol Neurobiol] 2021 Sep 21; Vol. 296, pp. 103790.
Date of Electronic Publication: 2021 Sep 21.

Background: Cardiopulmonary exercise testing (CPET) is a method used to evaluate functional impairment of patients with various diseases.
Objective: The objective was to use CPET to estimate the usability of anthropometric index (AI) in patients with pectus excavatum (PE) as a marker of functional impairment caused by chest deformity.
Methods: The study included 32 paediatric patients (28 males) with PE. Patients underwent CPET using a breath-by-breath exhaled gas analysis method and continuous monitoring of cardiac parameters.
Results: In both groups, two (overall four) patients met criteria for cardiogenic limitation (low VO ₂ and low O ₂ Pulse). Mean VO ₂ /WR was below two standard deviations (2SD) in patients with less severe PE; other observed parameters were within normal limits (Z-score ± 2 SD). The AI had no observed correlation with peak ventilation, VO ₂ peak and peak workload.
Conclusion: The obtained CPET data do not correlate well with the severity of chest deformity expressed with AI. There were similar physical activity limitations in both examined groups of patients and they did not depend on the severity of the deformity.

Vignati C; De Martino F; Muratori M; Salvioni E; Tamborini G; Bartorelli A; Pepi M; Alamanni F; Farina S;
Cattadori G;Mantegazza V; Agostoni P;

ESC heart failure [ESC Heart Fail] 2021 Sep 22. Date of Electronic Publication: 2021 Sep 22.

Aims: Changes in peak exercise oxygen uptake (VO ₂ ) and cardiac output (CO) 6 months after successful percutaneous edge-to-edge mitral valve repair (pMVR) in severe primary (PMR) and functional mitral regurgitation (FMR) patients are unknown. The aim of the study was to assess the efficacy of pMVR at rest by echocardiography, VO ₂ and CO (inert gas rebreathing) measurement and during cardiopulmonary exercise test with CO measurement.
Methods and Results: We evaluated 145 and 115 patients at rest and 98 and 66 during exercise before and after pMVR, respectively. After successful pMVR, significant reductions in MR and NYHA class were observed in FMR and PMR patients. Cardiac ultrasound showed reverse remodelling (left ventricular end-diastolic volume from 158 ± 63 mL to 147 ± 64, P < 0.001; ejection fraction from 51 ± 15 to 48 ± 14, P < 0.001; pulmonary artery systolic pressure (PASP) from 43 ± 13 to 38 ± 8 mmHg, P < 0.001) in the entire population. These changes were significant in PMR (n = 62) and a trend in FMR (n = 53), except for PASP, which decreased in both groups. At rest, CO and stroke volume (SV) increased in FMR with a concomitant reduction in arteriovenous O ₂ content difference [ΔC(a-v)O ₂ ]. Peak exercise, CO and SV increased significantly in both groups (CO from 5.5 ± 1.4 L/min to 6.3 ± 1.5 and from 6.2 ± 2.4 to 6.7 ± 2.0, SV from 57 ± 19 mL to 66 ± 20 and from 62 ± 20 to 69 ± 20, in FMR and PMR, respectively), whereas peak VO ₂ was unchanged and ΔC(a-v)O ₂ decreased.
Conclusions: These data confirm pMVR-induced clinical improvement and reverse ventricular remodelling at a 6-month analysis and show, in spite of an increase in CO, an unchanged exercise performance, which is achieved through a ‘more physiological’ blood flow distribution and O ₂ extraction behaviour. Direct rest and exercise CO should be measured to assess pMVR efficacy.

Macarlupú JL; Vizcardo-Galindo G; Figueroa-Mujíca R; Voituron N; Richalet JP; Villafuerte FC;

Experimental physiology [Exp Physiol] 2021 Sep 23. Date of Electronic Publication: 2021 Sep 23.

New Findings: What is the central question of this study? What is the effect of sub-maximal aerobic exercise training on signs and symptoms of chronic mountain sickness (CMS) in Andean highlanders? What is the main finding and its importance? Aerobic exercise training effectively reduces hematocrit, ameliorates symptoms, and improves aerobic capacity in CMS patients, suggesting that a regular aerobic exercise training program might be used as a low-cost non-invasive/non-pharmacological management strategy of this syndrome.
Abstract: Excessive erythrocytosis (EE) is the hallmark sign of Chronic Mountain Sickness (CMS), a debilitating syndrome associated with neurological symptoms and increased cardiovascular risk. We have shown that unlike sedentary residents at the same altitude, trained individuals maintain hematocrit within sea-level range, and thus we hypothesize that aerobic exercise training (ET) might reduce excessive hematocrit and ameliorate CMS signs and symptoms. Eight highlander men (38 ± 12y) with CMS (hematocrit: 70.6 ± 1.9%, CMS score: 8.8 ± 1.4) from Cerro de Pasco-Peru (4340m) participated in the study. Baseline assessment included hematocrit, CMS score, pulse oximetry, maximal cardiopulmonary exercise testing, and in-office plus 24h ambulatory blood pressure (BP) monitoring. Blood samples were collected to assess erythropoietic, hemolysis, and cardiometabolic markers. ET consisted of pedaling exercise in a cycloergometer at 60% of VO _2peak for 1h/day, 4 days/week for 8 weeks, and participants were assessed at weeks 4 and 8. Hematocrit and CMS score decreased significantly by week 8 (to 65.6 ± 6.6%, and 3.5 ± 0.8, respectively, p<0.05), while VO _2peak and maximum workload increased with ET (33.8 ± 2.4 vs. 37.2 ± 2.0ml/min/kg, p<0.05; and 172.5 ± 9.4 vs 210.0 ± 27.8W, p<0.01; respectively). Except for an increase in HDL-C, other blood markers and BP showed no differences. Our results suggest that reduction of hematocrit and CMS symptoms result mainly from hemodilution due to plasma volume expansion rather than to hemolysis. In conclusion, we show that ET can effectively reduce hematocrit, ameliorate symptoms, and improve aerobic capacity in CMS patients, suggesting that regular aerobic exercise might be used as a low-cost non-invasive/non-pharmacological management strategy.

Reimberg MM; Ritti-Dias R; Selman JP; Scalco RS; Wandalsen GF; Solé D; Hulzebos HJ; Takken T; Corso SD;
Lanza FC;

Pediatric pulmonology [Pediatr Pulmonol] 2021 Sep 27. Date of Electronic Publication: 2021 Sep 27.

Purpose: Whether modified shuttle teste (MST) achieves maximal effort in children and adolescents with asthma is unclear. The aim was to compare the physiological responses of MST to the cardiopulmonary exercise test (CPET) in pediatric patients with asthma, to observe its convergent validity.
Patients and Methods: cross sectional study, volunteers with asthma (6 to 17 years of age) under regular treatment. The MST is an external-paced test, and the participants were allowed to walk/run. CPET was performed on a cycle ergometer to compare with MST. Gas exchange (VO ₂ , VCO ₂ , and VE) and heart rate (HR) were the outcomes, and continuously assessed in both tests.
Results: 47 volunteers were included, normal lung function FEV1/FVC 88.6 (7.7). VO _2peak was higher at MST (2.0 ± 0.6 L/min) compared to CPET (1.6 ± 0.5 L/min), p< 0.001. Similar to VE at MST (50 ± 16 L/min) vs at CPET (40 ± 13 L/min), and VCO ₂ , at MST (2.1 ± 0.8 L/min) vs CPET (1.7 ± 0.6 L/min), p < 0.001. HR was also higher at MST (94 ± 6%pred) vs CPET (87 ± 8%pred), p=0.002. VO _2peak in MST correlated to the CPET (r = 0.78, p < 0.001). The ICC of VO _2peak between tests was 0.73 (0.06 – 0.89), p<0.001, and VO2peak Bland-Altman analysis showed bias of 0.46L/min.
Conclusion: the MST showed maximal physiologic response in children and adolescents with asthma. It is valid test, and can be used as an alternative to evaluate exercise capacity.

Gropper H; Mattioni Maturana F; Nieß AM; Thiel A;

Frontiers in sports and active living [Front Sports Act Living] 2021 Sep 01; Vol. 3, pp. 729090.
Date of Electronic Publication: 2021 Sep 01 (Print Publication: 2021).

Regular exercise fosters fitness-enhancing benefits. We assume that exercise interventions become successful and sustainable if physiological benefits of exercise are also subjectively perceivable. The goal of this study was to examine how young inactive adults physiologically respond to an exercise intervention and how those responses are subjectively experienced . Furthermore, we aimed to assess whether the sequence of two distinct endurance-based exercise modes has an impact on physiological and subjectively experienced physical fitness. Thirty-one young inactive adults were assessed for this substudy of the larger iReAct study. Participants were randomly assigned to a high-intensity interval training (HIIT) or a moderate-intensity continuous training (MICT) group for 6 weeks and subsequently switched groups for a second training period. Physiological fitness data was collected at baseline, follow-up I, and follow-up II using a graded cardiopulmonary exercise test. Subjectively reconstructed (i.e., retrospective constructions) experiences relating to physical fitness were assessed at follow-up II using a biographical mapping method. A repeated-measures one-way ANOVA on each training group was performed to see whether physiological and subjectively experienced fitness differed across training periods. The rate of change between all variables was calculated for the first and the second training period in order to compare the agreement between physiological and subjective fitness improvements. Participants increased their fitness across the intervention period both physiologically and subjectively. However, the rate of change depended on the sequence of the two training modes. While VO _2max increased significantly in both training periods in the MICT-HIIT sequence, a significant increase in VO _2max in the HIIT-MICT sequence was only observed in the HIIT period. Participants similarly perceived those increases subjectively in their exercise-related physical fitness, although they experienced a significant decrease in the second period of the HIIT-MICT sequence. For subjectively perceived physical fitness relating to everyday activities, significant increases were only observed for the first period of the MICT-HIIT sequence. Young inactive adults can improve both their physiological and their subjectively perceived fitness through regular exercise. However, exercise modes and their sequence can make a substantial difference regarding measured and perceived physical fitness. Additionally, despite a favorable tendency toward HIIT over MICT, inter- and intra-individual variability, particularly in the subjective experiences of fitness, reiterates the necessity of individualized approaches to exercise.