Home-based long-term physical endurance and inspiratory muscle training in children and adults with Fontan circulation

Background and study aim

Regular physical activity is highly recommended for patients with Fontan hemodynamics. Our aim was to investigate the effects of a long-term individualized home-based endurance training (IHET) on a bicycle ergometer in combination with inspiratory muscle training (IMT) in pediatric and adult patients after Fontan palliation. Additionally, factors influencing the trainability of Fontan palliated patients were analyzed.

Methods

From 2018 to 2021 a single-center prospective study was performed initially including 25 Fontan palliated patients. During study period nine patients were excluded due to incompliance. A Magbike® bicycle ergometer (DKN Technology, France) was used for IHET and a POWERbreathe® Medic plus device (HaB GmbH, Germany) was utilized for the IMT. Over the study period, bike training was increased from 90 min of basic endurance training per week to additional 25 min of interval training per week. IMT consisted of 30 breaths per day for 6-7 days per week with pressure adaption over time. Patients underwent cardiopulmonary exercise testing (CPET) and body plethysmography including measurement of respiratory muscle strength at baseline and at follow-up examinations at 4, 10 and 22 months.

Results

Follow-up examinations were completed by 18/25 patients (72.0%) at 4 and 10 months and 16/25 patients (64.0%) at 22 months. Median exercise capacity slightly increased by 0.13 W/kg from baseline to last follow-up (p = 0.055, 95%CI: 0.0-0.36). However, a significant increase of oxygen pulse of 0.7 ml/beat (p = 0.006, 95%CI: 0.38-2.22) was detectable. IMT significantly improved respiratory function with an increase of inspiratory vital capacity (VCin/reference) by 4.0% (p = 0.016, 95%CI: 0.8-8). Median maximal inspiratory pressure increased by 1.2 kPa (p = 0.003, 95%CI: 0.64-3.19) and expiratory pressure by 1.5 kPa (p = 0.036, 95%CI: 0.08-2.29). No adverse events or unplanned interventions occurred during the study. Patients' subjective quality of life did not significantly change over the study period.

Conclusion

In Fontan palliated patients, IHET in combination with IMT leads to a significant increase in oxygen pulse, inspiratory vital capacity as well as median maximal inspiratory and expiratory pressure but not to significant improvement of quality of life. Fontan patients should be encouraged to perform regular home-based exercise training.

Cardiopulmonary Exercise Test and Daily Physical Activity in Pediatric Congenital Heart Disease: an Exploratory Analysis

Sedentary lifestyle is reported to be associated with diminished exercise capacity, resulting in increased cardiovascular risk in adults with congenital heart disease (CHD). This cross-sectional study examined the association between objectively measured physical activity (PA) and exercise capacity in children and adolescents with CHD. Therefore, 107 patients (aged 13.0 ± 2.7 years, 41 girls) with various CHD performed a cardiopulmonary exercise test to quantify their peak oxygen uptake (peakV'O2). Moderate to vigorous PA (MVPA) and daily step count were assessed using Garmin vivofit jr. (Garmin, Germany) for 7 consecutive days. For association between PA and submaximal exercise capacity, Spearman correlation was performed. Patients with CHD showed almost normal values compared with the reference (79.5 ± 17.2% [31.6 to 138.1] %peakV'O2 predicted), with roughly normal ventilatory anerobic thresholds (50.6 ± 14.0% [20.3 to 97.9] % oxygen uptake at ventilatory anaerobic threshold [VATV'O2]). Step counts are below the recommendations (9,304 ± 3,792 steps/day [1,701 to 20,976]), whereas MVPA data are above the recommendations for children with ≥60 min/day (83.6 ± 34.6 min/day [10.1 to 190.9]). The Spearman rho showed significant positive correlations to VATV'O2 (r = 0.353, p <0.001) and %VATV'O2 (r = 0.307, p = 0.001), with similar results regarding MVPA (VATV'O2: r = 0.300, p = 0.002 and %VATV'O2: r = 0.270, p = 0.005). In conclusion, submaximal exercise capacity and PA correlate positively, making both assessments relevant in a clinical setting: PA in the context of cardiovascular prevention and peakV'O2 as the strongest predictor for morbidity and mortality.

"Quality of life" analysis in the long-term follow-up after "Fontan" palliation for CHDs-a single-centre experience

BACKGROUND

Complex CHDs are life threatening, and surgical treatment is needed for survival. Fontan palliation led to a significant increase in survival rates during the last decades. Consequently, quality of life became more essential. While a reduced quality of life compared to healthy children has been reported, detailed knowledge about individual quality of life and particular areas is lacking. Furthermore, the effect of different risk factors on quality of life is only rarely evaluated.

METHOD AND RESULTS

Database of the department for pediatric cardiology, Heart Center Leipzig, was screened for children after total cavopulmonary connection palliation. n = 39 patients were included in the study, the outcome after total cavopulmonary connection was analysed in detail and quality of life data were collected and analysed using the standardised questionnaire "Pediatric quality of life inventory", version 4.0. We compared the total health score of our patients to the mean score of healthy children in the literature. The mean follow-up time was 6.4 ± 3.2 years, the overall survival was 100% after maximal follow-up time of 11.1 years. We could not find any age or gender dependence, nor an influence of age at total cavopulmonary connection on the later quality of life. Yet, patients with three-staged surgery exhibited a worse quality of life than patients with two-staged palliation. Late complications might influence quality of life, but patient number is too small, to find universal results.

CONCLUSION

The total cavopulmonary connection palliation affects physical and psychological quality of life as well as cardiac health independently from age and gender. More patients and longer observation should be examined to confirm the results.

Development and Initial Validation of a Frailty Score for Pediatric Patients with Congenital and Acquired Heart Disease

Frailty is a multi-dimensional clinical syndrome that is associated with increased morbidity and mortality and decreased quality of life. Children/adolescents with heart disease (HD) perform significantly worse for each frailty domain compared to non-HD peers. Our study aimed to create a composite frailty score (CFS) that can be applied to children/adolescents with HD and evaluate associations between the CFS and outcomes. Children and adolescents (n = 30) with HD (73% single ventricle, 20% heart failure, 7% pulmonary hypertension) were recruited from 2016 to 2017 (baseline). Five frailty domains were assessed at baseline using measures validated for pediatrics: (1) Slowness: 6-min walk test; (2) Weakness: handgrip strength; (3) Fatigue: PedsQL Multi-dimensional Fatigue Scale; (4) Body composition: triceps skinfold thickness; and (5) Physical activity questionnaire. Frailty points per domain (range = 0-5) were assigned based on z-scores or raw questionnaire scores and summed to produce a CFS (0 = least frail; 25 = most frail). Nonparametric bootstrapping was used to identify correlations between CFS and cross-sectional change in outcomes over 2.2 ± 0.2 years. The mean CFS was 12.5 ± 3.5. In cross-sectional analyses of baseline data, correlations (|r|≥ 0.30) were observed between CFS and NYHA class, the number of ancillary specialists, total prescribed medications, heart failure medications/day, exercise test derived chronotropic index and percent predicted VO2peak, and between child and parent proxy PEDsQL. At follow-up, CFS was correlated with an increase in the number of heart failure medications (r = 0.31). CFS was associated with cross-sectional outcomes in youth with heart disease. Longitudinal analyses were limited by small sample sizes due to loss to follow-up.

Cardiovascular Imaging-Derived Skeletal Muscle Mass Correlates With Fitness and Survival in Patients With Univentricular Circulation

Aims This study aims to retrospectively quantify skeletal muscle mass from cardiovascular imaging studies in total cavopulmonary connection (TCPC) patients and to correlate calculated muscle mass with clinical outcomes. Materials and methods Ninety-one TCPC patients at a mean age of 24.0 ±5.5 years (37 women; 40.7%) who underwent chest computed tomography (CT) or cardiac magnetic resonance imaging (MRI) as part of their follow-up were identified in a single-center database. The cross-sectional skeletal muscle index (SMI) at the Th4 and Th12 levels was calculated from CT images, and the dorsal skeletal muscle area (SMA) at the Th12 level was measured from an MRI. Results Calculated SMI at Th12 level was 38.0 (34.5; 42.0) cm2.m-2 or 89.6 (81.9; 101.6) % of predicted values. The median follow-up from CT was 5.9 (3.1; 8.5) years, and the composite endpoint (death N=5, heart transplant N=6) was reached in a total of 11 (26.8%) patients. Patients with SMI (Th12) less than 90% of predicted values had a hazard ratio of 5.8 (95% CI: 1.2; 28.3) (p=0.03) for endpoint achievement. In the MRI group, dorsal SMA at the Th12 level was 27.6 ±5.1 cm2 in men and 20.0 ±5.8 cm2 in women. Correlations were found between SMA/kg and peak oxygen uptake (VO2 peak) (r=0.48, p=0.0005) and fat-free mass (r=0.63, p<0.0001), respectively. Conclusions A low SMI at the Th12 level was associated with a higher risk of death or cardiac transplantation. Evaluation of skeletal muscle mass using cardiovascular imaging methods allows rapid identification of individuals at risk of sarcopenia.

Patterns of WISC-V Performance in Children with Congenital Heart Disease

Congenital heart disease (CHD) is one of the most common congenital birth defects. As surgical and interventional techniques have improved, the mortality has been greatly reduced and the focus has shifted to quality of life and long-term outcomes. The impact of CHD on development and cognition is becoming increasingly recognized. However, more research is needed to understand how children with CHD perform across various cognitive and intellectual domains. This study explored the performance of children with CHD on the newest version of the Wechsler Intelligence Scale for Children compared to normative controls. Children with CHD performed more poorly than normal controls across all indices and most subtests with large effect sizes. Additionally, we explored the patterns of impairment across indices and subtests, as well as the relationships between heard disease variables and WISC-V performance. Block design, Digit Span, and Similarities were the most commonly impaired scores in children with CHD, while Symbol Search, Picture Span, Figure Weights, and Vocabulary were least likely to be impaired.

Body plethysmography - additional information on exercise capacity in patients with congenital heart disease?

AIMS

In each cardiopulmonary exercise test (CPET), resting spirometry is performed in advance. In patients with a congenital heart defect (CHD), lung volumes are often impaired. This study investigates correlations between lung volumes and CPET parameters and determines, whether body plethysmography provides substantial additional information for these patients.

METHODS

Data from 102 patients (23.8 ± 10.4 years of age, 39 female) with various forms of CHD were examined from April 2018 to October 2022. All patients underwent spirometry (measuring forced vital capacity, FVC and forced expiratory volume in 1 s, FEV1), body plethysmography (measuring total lung capacity, TLC) and an exhausting CPET. Data is presented as the median and interquartile range (z-scores) and correlated with Spearman's rho.

RESULTS

Fifty-five% of all patients had normal results in lung function and 45% had normal peak oxygen uptake (≥ 80% predicted in peak VO2). Patients with impaired lung function were significantly more likely to have low exercise capacity (Fisher's exact test: p = 0.028). FVC z-values and %predicted peak VO2 (r = 0.365, p < 0.001) correlated significantly as well as FEV1_z and %predicted peak VO2 (r = 0.320, p = 0.001), and TLC z-values and %predicted peak VO2 (r = 0.249, p = 0.012). No correlation was found between FEV1/FVC z-values and %predicted peak VO2 (r = -0.043, p = 0.670).

CONCLUSION

Spirometry and exercise capacity positively correlate, also in CHD patients. However, body plethysmography does not provide additional or improved prediction and is therefore only recommended in noteworthy results in spirometry to exclude further lung co-morbidities.

Impact of pulsatile pulmonary blood flow on cardiopulmonary exercise performance after the Fontan procedure

Objective

To evaluate the exercise capacity in patients following Fontan-Kreutzer, Fontan-Björk, and total cavopulmonary connection (TCPC).

Methods

Patients who performed exercise capacity tests at least once after the Fontan procedure between 1979 and 2007 were included. Patients after Fontan-Björk procedure were divided into 2 groups according to the pulmonary blood flow (PBF) pattern: patients with pulsatile PBF and those without. Peak oxygen uptake (VO2) was measured and percent-predicted VO2 was calculated.

Results

A total of 227 patients were nominated. The types of Fontan procedure included Fontan-Kreutzer in 48 (21.1%) patients, Fontan-Björk in 38 (16.7%); 11 (4.8%) with pulsatile PBF and 27 (11.9%) without pulsatile PBF; and TCPC in 141 (62.1%). Median age at the Fontan procedure was 4.5 years (interquartile range, 2.1-8.2 years). A total of 978 cardiopulmonary exercise tests were performed at median follow-up of 17.7 years (interquartile range, 11.3-23.4 years) postoperatively. Analysis using linear mixed-effects models demonstrated that percent-predicted VO2 was greater in patients with pulsatile PBF after Fontan-Björk compared with patients after other types of Fontan procedure (P < .001). The same results were obtained when the longitudinal percent predicted VO2 was performed using only patients with tricuspid atresia and double inlet left ventricle (P < .001).

Conclusions

Among long-term survivors after various types of Fontan procedures, patients with pulsatile PBF after the Fontan-Björk procedure demonstrated better exercise performance compared to those after TCPC, those after the Fontan-Kreutzer procedure, and those after the Fontan-Björk procedure with non-pulsatile PBF. The results implicate the importance of pulsatile PBF to maintain the Fontan circulation.

Exercise capacity in the Danish Fontan population remains stable after ten years of follow-up - is physical activity the key to success?

BACKGROUND

Most Fontan patients have impaired exercise capacity, and a further decline in exercise capacity over time seems inevitable. However, few longitudinal studies exist, and there is a lack of data from newer eras. We aimed to describe the natural evolution of exercise capacity over a 10-year period in a contemporary, population-based cohort of Danish Fontan patients.

METHODS

The study was a nationwide, prospective study. A cardiopulmonary exercise test (CPET) was used to assess the exercise capacity. All Danish Fontan patients who participated in a national study in 2011 (CPET1), were invited to a follow-up visit in 2021 (CPET2). All patients who completed CPET1 and CPET2 with a respiratory exchange ratio over 1.0 were included. The main outcome was percent predicted VO2peak (%pred VO2peak). At the time of CPET2, patients filled out a questionnaire including questions regarding physical activity.

RESULTS

Seventy-seven patients completed both CPET1 and CPET2, and seventy patients completed the questionnaire. The time interval between the two CPETs was 10.4 ± 0.9 years. The median age was 15 years at CPET1 and 26 years at CPET2. The exercise capacity remained stable with a mean %pred VO2peak of 53.8 ± 11.3 at CPET1 and 55.6 ± 10.9 in CPET2 (p = 0.314). Higher levels of vigorous physical activity were associated with higher %pred VO2peak in CPET2 in a multivariate regression model.

CONCLUSION

The %pred VO2peak remained stable over a ten-year period in this population-based Fontan cohort. Higher levels of self-reported vigorous physical activity were associated with higher %pred VO2peak in the most recent CPET.

Life satisfaction, health-related quality of life and physical activity after treatment for valvular aortic stenosis

OBJECTIVE

To investigate health-related quality of life and life satisfaction in children and adolescents treated for isolated congenital valvular aortic stenosis compared to healthy peers. Our second aim was to investigate the relationship between objectively measured physical activity, health-related quality of life and life satisfaction in the same group.

METHODS

Forty-eight patients, 8-18 years of age, were recruited, as well as 43 healthy peers matched for age, gender and residential area. Health-related quality of life was assessed by the KIDSCREEN-52 self-report and parent proxy report, and life satisfaction was evaluated with the Satisfaction With Life Scale. Physical activity was measured with an accelerometer for 7 days. Sports participation was self-reported.

RESULTS

No differences in the health-related quality of life domains were found between patients and controls in the self-reports. In the proxy reports, parents of the adolescents rated their child's autonomy lower than did the parents of the healthy controls. A negative relationship was found between moderate to vigorous physical activity, sports participation, life satisfaction and the psychological well-being domain in adolescent patients. In children there was a positive relationship between moderate physical activity and the physical and psychological well-being domains.

CONCLUSION

Overall, children and adolescents treated for valvular aortic stenosis reported similar life satisfaction and health-related quality of life as their healthy peers. The negative relationships between intense physical activity and sports participation with health-related quality of life and life satisfaction in adolescent patients might be explained by both physical and psychological factors in these teenagers with complex, lifelong heart disease.

Right Ventricular Electromechanical Dyssynchrony and Its Relation to Right Ventricular Remodeling, Dysfunction, and Exercise Capacity in Ebstein Anomaly

BACKGROUND

Abnormal atrioventricular and intraventricular electrical conduction and dysfunction of the functional right ventricle (fRV) are common in Ebstein anomaly (EA). However, fRV mechanical dyssynchrony and its relation to fRV function are poorly characterized. We evaluated fRV mechanical dyssynchrony in EA patients in relation to fRV remodeling, dysfunction, and exercise intolerance.

METHODS

We retrospectively analyzed data from nonoperated EA patients and age-matched controls who underwent echocardiography, cardiovascular magnetic resonance imaging, and cardiopulmonary exercise testing to quantify right ventricular (RV) remodeling, dysfunction, and exercise capacity. The relation of these to fRV dyssynchrony was retrospectively investigated. Right ventricular mechanical dyssynchrony was defined by early fRV septal activation (right-sided septal flash), RV lateral wall prestretch/late contraction, postsystolic shortening, and intra-RV delay using two-dimensional strain echocardiography. The SD of time to peak shortening among the fRV segments was calculated as a parameter of mechanical dispersion.

RESULTS

Thirty-five EA patients (10 of whom were <18 years of age) and 35 age-matched controls were studied. Ebstein anomaly patients had worse RV function and increased intra-RV dyssynchrony versus controls. Nineteen of 35 (54%) EA patients had early septal activation with simultaneous stretch and consequent late activation and postsystolic shortening of RV lateral segments. Intra-fRV mechanical delay correlated with fRV end-diastolic volume index (r = 0.43, P < .05) and fRV end-systolic volume index (r = 0.63, P < .001). The fRV ejection fraction was lower in EA with versus without right-sided septal flash (44.9 ± 11.0 vs 54.2 ± 8.2, P = .012). The fRV mechanical dispersion correlated with the percentage of predicted peak VO₂ (r = -0.35, P < .05).

CONCLUSIONS

In EA, fRV mechanical dyssynchrony is associated with fRV remodeling, dysfunction, and impaired exercise capacity. Mechanical dyssynchrony as a therapeutic target in selected EA patients warrants further study.

Abnormalities in pulmonary function and volumes in patients with CHD: a systematic review

BACKGROUND

Lung function and cardiac function are naturally correlated by sharing the thoracic cage and handling the whole cardiac output sequentially. However, lung function studies are rare in patients with CHD, although results worthy of investigation could be expected. This review summarises existing studies with the lung function parameters (spirometry and body plethysmography) in CHD patients during the last decade.

METHODS

A systematic review was performed in the relevant database (PubMed, Cochrane, and Scopus) in studies including paediatric and adult patients with CHD where lung parameters (spirometry, body plethysmography) were investigated from January 2010 to December 2020. Two independent reviewers evaluated the studies according to the Study Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies of the National Heart, Lung, and Blood Institute.

RESULTS

Eight studies investigated patients with Fontan palliation including 704 patients (306 female). Four studies included patients after repaired tetralogy of Fallot examining 219 patients (103 female), with one study using double. Further six studies included 3208 (1324 female) children and adults with various CHDs. Overall, four studies were categorised as "good", ten as "fair", and four as "poor". While the measurements were consistently standardised, references to calculate %predicted differed substantially across all studies. All evaluated studies showed reduced forced vital capacity in the majority of CHD patients.

CONCLUSIONS

Many CHD patients have a reduced forced vital capacity independent of their underlying defect. Spirometry should not only follow a standardised measure according to ATS (update 2019) but also stick to the 2012 GLI reference values.

Cardiorespiratory fitness, muscle fitness, and physical activity in children with long QT syndrome: A prospective controlled study

Background

In children with congenital long QT syndrome (LQTS), the risk of arrhythmic events during exercise commonly makes it difficult to balance exercise restrictions versus promotion of physical activity. Nevertheless, in children with LQTS, cardiorespiratory fitness, muscle fitness, and physical activity, have been scarcely explored.

Materials and methods

In this prospective, controlled, cross-sectional study, 20 children with LQTS (12.7 ± 3.7 years old) and 20 healthy controls (11.9 ± 2.4 years old) were enrolled. All participants underwent a cardiopulmonary exercise test, a muscular architecture ultrasound assessment, (cross-sectional area on right rectus femoris and pennation angle), a handgrip muscular strength evaluation, and a standing long broad jump test. The level of physical activity was determined using with a waist-worn tri-axial accelerometer (Actigraph GT3X).

Results

Peak oxygen uptake (VO2peak) and ventilatory anaerobic threshold (VAT) were lower in children with LQTS than in healthy controls (33.9 ± 6.2 mL/Kg/min vs. 40.1 ± 6.6 mL/Kg/min, P = 0.010; 23.8 ± 5.1 mL/Kg/min vs. 28.8 ± 5.5 mL/Kg/min, P = 0.007, respectively). Children with LQTS had lower standing long broad jump distance (119.5 ± 33.2 cm vs. 147.3 ± 36.1 cm, P = 0.02) and pennation angle (12.2 ± 2.4° vs. 14.3 ± 2.8°, P = 0.02). No differences in terms of moderate-to-vigorous physical activity were observed (36.9 ± 12.9 min/day vs. 41.5 ± 18.7 min/day, P = 0.66), but nearly all children were below the WHO guidelines.

Conclusion

Despite similar physical activity level, cardiorespiratory fitness and muscle fitness in children with LQTS were lower than in healthy controls. The origin of this limitation seemed to be multifactorial, involving beta-blocker induced chronotropic limitation, physical and muscle deconditioning. Cardiovascular rehabilitation could be of interest in children with LQTS with significant physical limitation.

Physical Activity in Fontan Patients Relates to Quality of Life and Sleep Quality

Background and Aim

Fontan patients tend to have reduced physical exercise capacity. This study investigates physical activity (PA) and its relationship to exercise capacity, heart rates, cardiac function, biomarkers, health-related quality of life (HRQoL), and sleep quality.

Methods

Cardiovascular magnetic resonance (CMR), exercise testing (CPET), 24 h-ECG, and blood samples were prospectively performed in 38 patients, age 13 (11–16) years. PA was assessed by accelerometer during 7 consecutive days. HRQoL was self-assessed with KIDSCREEN-27 and SF-36 according to patients' age; sleep quality with Pediatric Sleep Questionnaire (PSQ) and Pittsburgh Sleep Quality Index (PSQI).

Results

Daily moderate to vigorous physical activity (MVPA) was in median (IQR) 40 (28–57) mins; 7/38 (18%) patients reached the recommended 60 mins/day of MVPA. MVPA did not correlate with gender, age, single ventricle morphology, time from Fontan, heart rate, ventricular volumes, and ejection fraction at CMR, biomarkers, or CPET. Physical wellbeing (r = 0.33, p = 0.04), autonomy (r = 0.39, p = 0.03), and social support (r = 0.43, p = 0.009) assessed using the KIDSCREEN-27, and both physical (r = 0.57, p = 0.03) and mental (r = 0.54, p = 0.04) domains of the SF-36 questionnaire correlated with daily minutes of MVPA. PSQI global sleeping score (r = −0.7, p = 0.007), and PSQ scales for behavior (r = −0.36; p = 0.03) correlated with daily minutes of MVPA.

Conclusion

Only 18% of the Fontan patients meet the recommendation for daily MVPA. Measures of exercise capacity, cardiac function or chronotropic competence are not correlated to daily physical activity. In contrast, HRQoL and sleep quality seem to be associated with regular physical activity.

Exercise Capacity and Training Programs in Paediatric Fontan Patients: A Systematic Review

Background

Exercise training programs can effectively enhance exercise capacity in adults with congenital heart disease, including Fontan patients. However, few studies have explored the impact of exercise training exclusively on paediatric Fontan cohorts. This study systematically reviews exercise capacity in paediatric Fontan patients and the impact of training programs on their cardiovascular health.

Methods

Medline and Embase were searched for articles published between January 1990 and November 2021. Studies were included in which data could be analyzed discretely for patients who had undergone the Fontan procedure and were ≤20 years old at the time of study. Cardiopulmonary exercise parameters were extracted from all studies, and training protocols were collected from training programs.

Results

The studies demonstrated that Fontan patients exhibit significantly diminished peak exercise capacity relative to healthy peers. We identified 9 training programs that exclusively studied Fontan patients ≤20 years. The programs ranged from 6 weeks to 12 months in duration, with 8 programs incorporating aerobic activity and 1 focused only on inspiratory muscle training. At least 1 measure of maximal or submaximal exercise capacity improved significantly within each program in which statistical analysis was performed, with no reported adverse events. There were 2 additional training programs in which the patients were predominantly (>65%), but not exclusively, Fontan patients.

Conclusions

Overall, the results indicate that exercise training programs can safely and effectively improve at least 1 measure of exercise capacity in paediatric Fontan patients.

Exercise Capacity in Children and Adolescents With Congenital Heart Disease: A Systematic Review and Meta-Analysis

Background

Congenital heart disease (CHD) entails structural defects in the morphogenesis of the heart or its main vessels. Analyzing exercise capacity of children and adolescents with CHD is important to improve their functional condition and quality of life, since it can allow timely intervention on poor prognostic factors associated with higher risk of morbidity and mortality.

Objective

To describe exercise capacity in children and adolescents with CHD compared with healthy controls.

Methods

A systematic review was carried out. Randomized clinical trials and observational studies were included assessing exercise capacity through direct and indirect methods in children and adolescents between 5 and 17 years-old. A sensitive analysis was performed including studies with CHD repaired participants. Additionally, it was sub-analyzed by age range (< and ≥ 12 years old). Two independent reviewers analyzed the studies, extracted the data, and assessed the quality of the evidence.

Results

5619 articles were found and 21 were considered for the review. Eighteen articles used the direct exercise capacity measurement method by cardiopulmonary exercise test (CPET). The CHD group showed significant differences in peak oxygen consumption (VO₂peak) with a value of −7.9 ml/Kg/min (95% CI: −9.9, −5.9, p = 0.00001), maximum workload (Wmax) −41.5 (95% CI: −57.9, −25.1 watts, p = 0.00001), ventilatory equivalent (VE/VCO₂) slope 2.6 (95% CI: 0.3, 4.8), oxygen pulse (O₂ pulse)−2.4 ml/beat (95% CI: −3.7, −1.1, p = 0.0003), and maximum heart rate (HRmax) −15 bpm (95% CI: −18, −12 bpm, p = 0.00001), compared with healthy controls. Adolescents (≥ 12 yrs) with CHD had a greater reduction in VO₂peak (−10.0 ml/Kg/min (95% CI: −12.0, −5.3), p < 0.00001), Wmax (−45.5 watts (95% CI: −54.4, −36.7), p < 0.00001) and HRmax (−21 bpm (95% CI: −28, −14), p<0.00001).

Conclusion

Suffering CHD in childhood and adolescence is associated with lower exercise capacity as shown by worse VO₂peak, Wmax, VE/VCO₂ slope, O₂ pulse, and HRmax compared with matched healthy controls. The reduction in exercise capacity was greater in adolescents.

Systematic Review Registration

www.crd.york.ac.uk/prospero/display_record.php?RecordID=208963, identifier: CRD42020208963.

Home-Based Long-Term Physical Endurance and Inspiratory Muscle Training for Children and Adults With Fontan Circulation—Initial Results From a Prospective Study

Background

Patients with congenital heart disease (CHD)—including those after Fontan operation—are encouraged to be physically active.

Aim

To prospectively determine the effects of an individually adapted, home-based cycle ergometer endurance training in combination with inspiratory muscle training (IMT) in pediatric and adult Fontan patients. We, herein, report the results of the initial 10-months follow-up (phase 1).

Methods

18 patients (median age 16.5 years; range 10-43 years) completed baseline check-ups, and 4 and 10 months follow-up visits, which each included cardiopulmonary exercise testing (CPET), bodyplethysmography (including measurement of respiratory muscle strength), and a quality of life questionnaire (PedsQL™). The training program consisted of a home-based cycle ergometer endurance training on a “Magbike® AM-5i/3i” (DKN Technology®, Clermont-Ferrand, France) and IMT with a handheld “POWERbreathe® Medic plus” device. Patients performed 90 min of endurance training per week in addition to IMT (30 breaths per day, 6-7 times per week). After the first 4 months, patients underwent additional interval training.

Results

After 10 months of training, we observed significant increases in maximum relative workload (W/kg, p = 0.003) and in maximum inspiratory (MIP, p = 0.002) and expiratory (MEP, p = 0.008) pressures. Peak VO2 values did not increase significantly as compared to baseline (p = 0.12) in the entire cohort (n = 18), but reached statistical significance in a subgroup analysis of teenage/adult patients (n = 14; p = 0.03). Patients' subjective quality of life did not show any significant changes after 10 months of training.

Discussion

In Fontan patients, an individually adapted home-based training is safe and associated with improvements in some CPET variables. However, these improvements did not translate into an improved QoL after 10 months. With an unclear, but most likely negative, impact of the COVID-19 pandemic, improvements in QoL may become evident during further follow-up (phase 2 of the study).

Calf Muscle Oxygenation is Impaired and May Decline with Age in Young Patients with Total Cavopulmonary Connection

Patients palliated with Total Cavopulmonary Connection have a lower muscle mass and a lower exercise capacity. We assessed calf muscle oxidative metabolism during and after heel raise exercise to exhaustion in young patients with TCPC compared to healthy peers. Near-infrared spectroscopy was used for measuring oxygen metabolism in the medial portion of the gastrocnemius muscle. Forty-three patients with TCPC, aged 6-18 years, were compared with 43 age and sex-matched healthy control subjects. Subgroups were formed to include children (6-12 years) and adolescents (13-18 years) to determine if these age groups influenced the results. During exercise, for the patients compared to controls there was a lower increase in deoxygenated hemoglobin (oxygen extraction) (5.13 ± 2.99au vs. 7.75 ± 4.15au, p = 0.001) and a slower rate of change in total hemoglobin (blood volume) (0.004 ± 0.015au vs 0.016 ± 0.01au, p = 0.001). Following exercise, patients exhibited a slower initial increase in tissue oxygenation saturation index (0.144 ± 0.11au vs 0.249 ± 0.226au, p = 0.007) and a longer half-time to maximum hyperemia (23.7 ± 11.4 s vs 16.8 ± 7.5 s, p = 0.001). On the subgroup level, the adolescents differed compared to healthy peers, whereas the children did not. Young patients with TCPC had impaired oxidative metabolism during exercise and required a longer time to recover. In that the differences were seen in the adolescent group and not in the children group may indicate a declining function with age.

Is the six-minute walk test still reliable compared to cardiopulmonary exercise test for exercise capacity in children with congenital heart disease?

OBJECTIVES

We aimed to assess the validity of the six-minute walk test (6MWT) to reflect the functional capacity of children with congenital heart disease (CHD), evaluate a possible correlation between the 6MWT distance with cardiopulmonary exercise test (CPET) variables, as well as to find a cutoff value to stratification the physical fitness in this population.

METHODS

We enrolled 459 children with CHD, 6-18 years old, who performed a complete CPET and 6MWT on the same day in a cross-sectional observational study. Correlations between variables of CPET and six-minute walking distance (6MWD) were analyzed and cutoff values of 6MWD were identified for the classification of the physical fitness in the population.

RESULTS

The mean distance ambulated during the 6MWT was 578 ± 65 m, 590 ± 65 m for boys, and 562 ± 62 m for girls (p < 0.001). Both VO_2max and %predicted VO_2max showed a correlation with the 6MWT distance (r = 0.35, p < 0.001 and r = 0.51, p < 0.001, respectively), and an inverse correlation was found between VE/VCO2 slope and the 6MWT distance (r = -0.31; p < 0.001). There appeared to be a linear association between 6MWD and VO_2max up to a 6MWD of approximately 600 m. We divided the population into 4 subgroups (boys <130 cm; boys ≥130 cm; girls <130 cm; girls ≥130 cm), and get the cutoff values (554 m, 617 m, 549 m, 587 m) respectively equivalent to 80% of predicted VO_2max. The 6MWT distances of another 102 patients were applied for external verification of the cutoff values.

CONCLUSIONS

Our study provided evidence on when a 6MWT should be considered as a convincing complementary test in the pediatric population with CHD and explored the classification of exercise tolerance using a 6MWD value. The cut-off values for 6MWD may be qualified as an intervention target for exercise rehabilitation.

Endurance training may improve exercise capacity, lung function and quality of life in Fontan patients

Children born with univentricular hearts undergo staged surgical procedures to a Fontan circulation. Long-term experience with Fontan palliation has shown dramatically improved survival but also of a life-long burden of an abnormal circulation with significant morbidity. Many Fontan patients have reduced exercise capacity, oxygen uptake, lung function and quality of life. Endurance training may improve submaximal, but not maximal, exercise capacity, lung function and quality of life. Physical activity and endurance training is also positively correlated with sleep quality. Reviewing the literature and from our single-centre experience, we believe there is enough evidence to support structured individualised endurance training in most young Fontan patients.

The "Super-Fontan" Phenotype: Characterizing Factors Associated With High Physical Performance

Background: People with a Fontan circulation usually have moderately impaired exercise performance, although a subset have high physical performance ("Super-Fontan"), which may represent a low-risk phenotype. Methods: People with a "Super-Fontan" phenotype were defined as achieving normal exercise performance [≥80% predicted peak oxygen uptake (VO₂) and work rate] during cardiopulmonary exercise testing (CPET) and were identified from the Australian and New Zealand Fontan Registry. A Fontan control group that included people with impaired exercise performance (<80% predicted VO₂ or work rate) was also identified based on a 1:3 allocation ratio. A subset of participants were prospectively recruited and completed a series of physical activity, exercise self-efficacy, and health-related quality of life questionnaires. Results: Sixty CPETs ("Super-Fontan", n = 15; control, n = 45) were included. A subset ("Super-Fontan", n = 10; control, n = 13) completed a series of questionnaires. Average age was 29 ± 8 years; 48% were males. Exercise capacity reflected by percent predicted VO₂ was 67 ± 17% in the entire cohort. Compared to the "Super-Fontan" phenotype, age at Fontan completion was higher in controls (4.0 ± 2.9 vs. 7.2 ± 5.3 years, p = 0.002). Only one (7%) person in the "Super-Fontan" group had a dominant right ventricle compared to 15 (33%) controls (p = 0.043). None of those in the "Super-Fontan" group were obese, while almost a quarter (22%) of controls were obese based on body mass index (p = 0.046). Lung function abnormalities were less prevalent in the "Super-Fontan" group (20 vs. 70%, p = 0.006). Exercise self-efficacy was greater in the "Super-Fontan" group (34.2 ± 3.6 vs. 27.9 ± 7.2, p = 0.02). Self-reported sports participation and physical activity levels during childhood and early adulthood were higher in the "Super-Fontan" group (p < 0.05). The total average time spent participating in structured sports and physical activity was 4.3 ± 2.6 h/wk in the "Super-Fontan" group compared to 2.0 ± 3.0 h/wk in controls, p = 0.003. There were no differences in self-reported current total physical activity score or health-related quality of life between groups (p ≥ 0.05). Conclusions: The "Super-Fontan" phenotype is associated with a healthy weight, lower age at Fontan completion, better exercise self-efficacy, and higher overall levels of sport and physical activity participation during physical development.

Exercise capacity after total cavopulmonary anastomosis: a longitudinal paediatric and adult study

AIMS

Fontan palliation is a surgical strategy for patients with complex congenital heart disease, in whom biventricular circulation cannot be achieved. Long-term survival is negatively affected by the absence of sub-pulmonary ventricle and increased systemic venous pressure. Exercise capacity is a known predictor of overall survival and quality of life in congenital heart defects. We aim to track individual trends of peak oxygen uptake (V̇O₂ peak) after total cavopulmonary connection (TCPC), identify predictors of deterioration, and derive a disease-specific reference V̇O₂ peak dataset.

METHODS AND RESULTS

A retrospective study of serial cardiopulmonary exercise testing (CPET) data, gathered from all patients who underwent TCPC in the Czech Republic between 1992 and 2016. Of 354 consecutive patients with TCPC, 288 (81.4%) patients underwent one or more CPETs yielding 786 unique V̇O₂ peak values used as a reference dataset. Longitudinal data were available in 206 (58.2%) patients, who underwent a median (inter-quartile range) of 3.0 (2.0-5.0) CPETs over a mean (standard deviation) of 8.9 (5.5) years. The decline of exercise capacity with age was linear and not faster than in healthy peers (P = 0.47), but relative values of V̇O₂ peak in TCPC patients were 12.6 mL/min/kg lower. Single ventricular morphology and pulmonary artery size had no significant influence on the exercise capacity dynamics. V̇O₂ peak decline correlated negatively with the trend of body mass index z-score (P = 0.006) and was faster in women than men (P = 0.008).

CONCLUSIONS

Total cavopulmonary connection patients have significantly reduced exercise capacity. The age-related decline paralleled the healthy population and correlated negatively with the body mass index trend. The presented V̇O₂ peak reference dataset may help the clinicians to grade the severity of exercise capacity impairment in individual TCPC patients.

Prognostic Value of Maximal and Submaximal Exercise Performance in Fontan Patients < 15 Years of Age

In patients after Fontan completion exercise capacity is significantly reduced. Although peak oxygen consumption (VO_2peak) is a strong prognostic factor in many cardiovascular diseases, it requires the achievement of a maximal effort. Therefore, submaximal exercise parameters such as oxygen uptake efficiency slope (OUES) may be of value. In the present observational study we evaluated the exercise capacity with maximal and submaximal parameters in a group of Fontan patients with an extracardiac conduit and determined their prognostic value. Sixty Fontan patients followed up in the Leiden University Medical Center who have performed an exercise test were included in this retrospective study. Exercise tests were performed at a median age of 11 years. Fontan patients showed on average lower values for all exercise parameters compared to reference values from a healthy dataset as shown by the %predicted values: VO_2peak%:mean 66%(95%CI:64 to 74) and OUES%:mean 72%(95%CI:67 to 77). Twenty percent of the patients were not able to achieve an RER>1.0. RER showed a moderate positive correlation with VO_2peak but not with OUES. There was a deterioration of VO_2peak% and OUES% over time. OUES was significantly lower in patients with cardiac events in the follow up period. Fontan patients have an impaired exercise performance even at young ages and it deteriorates with age. An important percentage of Fontan patients is not able to reach maximal effort so the use of submaximal parameters, like OUES, should be considered as part of the evaluation. Moreover, OUES could have a prognostic value in this group of patients.

Physical activity modification in youth with congenital heart disease: a comprehensive narrative review

Congenital heart disease (CHD) affects nearly 1% of births. As survival rates have dramatically improved, the majority of individuals with CHD now live into adulthood. As these patients age, they become prone to a large range of complications, such as chronic heart failure and acquired cardiovascular disease. Promotion of a healthy and active lifestyle from childhood onwards has been suggested as a sustainable and effective strategy to enhance cardiovascular health, improve quality of life and reduce immediate and long-term risk in people with CHD. Well-established physical activity consensus statements for youth with CHD have now been published. In this article, we review how increasing physical activity in youth with CHD may offer immediate and long-term cardiovascular benefits, what is known about physical activity in children with CHD, describe the unique factors that contribute to achieving sufficient and insufficient physical activity levels and summarize the evidence of trials on physical activity promotion in youth with CHD. Furthermore, we discuss some of the challenges that need to be addressed by further research regarding the optimal strategy, timing and format of physical activity intervention programmes in children and adolescents with CHD. IMPACT: Congenital heart disease (CHD) affects nearly 1% of births, with the majority of individuals with CHD now living into adulthood due to improved survival. As CHD patients age, they become prone to a large range of cardiovascular complications. This article discusses how and why increasing physical activity in youth with CHD may offer immediate and long-term cardiovascular benefits, the barriers to achieving sufficient physical activity levels and the evidence from trials on physical activity promotion in youth with CHD. The optimal strategy, timing and format of physical activity intervention programmes in children and adolescents with CHD are discussed.

Objective Physical Activity Assessment in Clinical Congenital Heart Disease Research: A Systematic Review on Study Quality, Methodology, and Outcomes

BACKGROUND

The shift toward a preventative approach in medical aftercare of congenital heart disease (CHD) patients has led to encouragement of regular physical activity (PA) in this patient population. Objective measures are crucial in accurately displaying PA levels and have increasingly found their way into clinical research. This review aims to give an overview about quality, methodology, and outcomes of current scientific work on accelerometers objectively assessing PA in patients with CHD.

METHODS

Systematically researched literature in all relevant databases (PubMed, Cochrane, and Scopus) over the past decade (2009-2019) with history of CHD and accelerometer-based PA assessment was evaluated by 2 independent reviewers according to the Study Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies of the National Heart, Lung, and Blood Institute.

RESULTS

Eight articles with 664 pediatric patients with CHD aged 3-18 years (range 10-162 patients), 5 studies with 574 adults with CHD aged 18-63 years (range 28-330 patients), and 3 studies with 177 pediatric patients and adults with CHD aged 8-52 years were included. Two studies were rated "good"; 9, "fair"; and 5, "poor." Methodologies and devices differed substantially across all studies.

CONCLUSIONS

Overall study quality was fair at best, and due to difficult methodological comparability of the studies, no clear answer on how active patients with CHD really are can currently be given. Larger studies carefully considering collection and processing criteria, and correct reporting standards exploring PA in patients with CHD from different angles are needed.

Quality of life of adult Fontan patients

BACKGROUND

Progress in the management of complex congenital heart disease (CHD) led to an improvement in survival rates of adults with a Fontan-like circulation. The objective of this study was to assess the subjective health status and quality of life of this population.

METHODS AND RESULTS

Patients aged more than 18 years at the time of the study, who underwent a Fontan-like procedure. Subjective health status was assessed by the SF-36 questionnaire and a linear analog scale was used to score patients' self-perception of their quality of life; cardiac and demographic parameters were collected.

RESULTS

Among 65 eligible patients, 60 (23 females; mean ± SD age: 25.7 ± 7.2 years) answered the SF-36 questionnaire and 46 of these were interviewed to evaluate their perceived quality of life. Among them, 20 (33.3%) were working full-time and 21 (35%) experienced arrhythmias. The physical SF-36 scores were lower in patients than in the general population (p ≤ 0.05). The New York Hear Association (NYHA) class and occupation were correlated with SF-36 scores of physical activity (respectively, p = 0.0001 and p = 0.025). SF-36 scores of psychological status were associated with the number of drugs and occupation (respectively, p = 0.0001 and p = 0.02). The mean ± SD quality of life score measured using a linear analog scale was 7.02 ± 1.6 and was linked to education and occupation (p ≤ 0.05) but not with cardiac parameters.

CONCLUSION

Adult Fontan patients perceive an impaired physical health but report a good overall quality of life. Education and occupation impacts significantly on Fontan patients' quality of life.

Mismatch between self-estimated and objectively assessed exercise capacity in patients with congenital heart disease varies in regard to complexity of cardiac defects

AIM

Regular evaluation of physical capacity takes a crucial part in long-term follow-up in patients with congenital heart disease (CHD). This study aims to examine the accuracy of self-estimated exercise capacity compared to objective assessments by cardiopulmonary exercise testing in patients with CHD of various complexity.

METHODS

We conducted a single centre, cross-sectional study with retrospective analysis on 382 patients aged 8-68 years with various CHD who completed cardiopulmonary exercise tests. Peak oxygen uptake was measured. Additionally, questionnaires covering self-estimation of exercise capacity were completed. Peak oxygen uptake was compared to patient's self-estimated exercise capacity with focus on differences between complex and non-complex defects.

RESULTS

Peak oxygen uptake was 25.5 ± 7.9 ml/minute/kg, corresponding to 75.1 ± 18.8% of age- and sex-specific reference values. Higher values of peak oxygen uptake were seen in patients with higher subjective rating of exercise capacity. However, oxygen uptake in patients rating their exercise capacity as good (mean oxygen uptake 78.5 ± 1.6%) or very good (mean oxygen uptake 84.8 ± 4.8%) was on average still reduced compared to normal. In patients with non-complex cardiac defects, we saw a significant correlation between peak oxygen uptake and self-estimated exercise capacity (spearman-rho -0.30, p < 0.001), whereas in patients with complex cardiac defects, no correlation was found (spearman-rho -0.11, p < 0.255).

CONCLUSION

The mismatch between self-estimated and objectively assessed exercise capacity is most prominent in patients with complex CHD.Registration number at Charité Universitätsmedizin Berlin Ethics Committee: EA2/106/14.

Sedentary Behavior in Childhood, Lower Arterial Compliance and Decreased Endothelial Function-Cross Sectional Data From a German School Cohort

BACKGROUND

Endothelial function by flow-mediated dilatation assesses early markers of atherosclerotic progression. Greater amounts of physical activity and physical fitness in children are associated with cardiovascular health benefits. We aimed to explore factors, influencing endothelial function and arterial compliance in a cohort of healthy school children.

METHODS

The 94 participants (41 girls, 53 boys) in the study were young, healthy children from a German school cohort. Anthropometric data, body composition and blood pressure were assessed. Blood was drawn (8 h overnight fast), assessing total cholesterol, high density lipoprotein and low density lipoprotein and triglycerides. Endothelial function was diagnosed by flow-mediated dilatation with ultrasonography (ALOKA/Hitachi, Prosound alpha 6). Tracking gates were set on the intima in B-mode. The waveform of diameter changes over the cardiac cycle was displayed in real time using the FMD-mode of the eTRACKING system. Changes in arterial diameter at baseline, ischaemia and vasodilatation were measured. A symptom limited pulmonary exercise test on a bicycle ergometer was performed to test cardiorespiratory fitness. Physical activity was assessed using GT3x accelerometers (Actigraph, USA), over 4 days (including 1 week-end day), with a minimum wear-time duration of 10 h.

RESULTS

The median age was 12.2 years (11.8-12.8). Children were normal weight, blood lipid profiles (cholesterol, high-density lipoprotein, low-density lipoprotein, triglyceride) were in normal range. Baseline measurements during the diagnostics of endothelial function revealed higher arterial compliance of the brachial artery in boys. Boys' cardiorespiratory fitness was higher than compared to girls. Boys met the recommendations of 60 min moderate to vigorous activity, whereas girls were significantly less active and did not meet current recommendations. More time spent in sedentary activity was the main predictor for lower arterial compliance (adjusted for age and sex), accounting for 14% of the variance. No significant model revealed, analyzing the influencing factors such as anthropometric data, blood lipids, physical activity and fitness on endothelial function.

CONCLUSION

This is the first study on endothelial function in association to objectively measured physical activity and cardiorespiratory fitness in healthy school children in Germany. The study highlights the importance of reducing time spent being sedentary to maintain endothelial health.

End-Organ Function and Exercise Performance in Patients With Fontan Circulation: What Characterizes the High Performers?

Background The physiologic hallmarks of the Fontan circulation-chronically elevated central venous pressures and low cardiac output-have significant effects not only on cardiovascular status but also impact other organ systems. Exercise capacity is limited in many and declines with age, accelerating in adolescence, but with wide variability. We explore the relationship between exercise performance and end-organ function in outpatient subjects with a Fontan circulation. Methods and Results This is a cross-sectional analysis of subject end-organ characterization from our outpatient Fontan circulation clinic with peak oxygen consumption (peak Vo₂) at cardiopulmonary exercise testing as the primary outcome. We perform linear regression to assess associations between clinical characteristics and peak Vo₂ as well as the magnitude of the association of clinical characteristics with peak Vo₂. Of 265 subjects age 12.8 (9.5-16.4) years, there is a negative correlation between age and peak Vo₂ (-0.49, P<0.001). Of those undergoing ramp cycle exercise testing, 34% perform above 80% predicted peak Vo₂. Variables positively associated with peak Vo₂ and their effect size include vitamin D sufficiency (+3.00, P=0.020) and absolute lymphocyte count (+0.23, P=0.005). Status as overweight/obese (-3.91, P=0.003) and hemoglobin (-0.77, P=0.003) are negatively associated. Neither ventricular morphology, timing of Fontan palliation, nor Fontan circulation type affect peak Vo₂. Conclusions Higher peak Vo₂ in those with a Fontan circulation is associated with younger age, vitamin D sufficiency, absence of overweight/obese, lower hemoglobin, and a healthier hepatic profile. Whether exercise training or other initiatives can modify organ characteristics in those with a Fontan circulation is worthy of exploration.

Physical Activity Patterns in Children and Adolescents With Heart Disease

PURPOSE

To quantify the differences in daily physical activity (PA) patterns, intensity-specific volumes, and PA bouts in youth with and without heart disease (HD).

METHODS

Seven-day PA was measured on children/adolescents with HD (n = 34; median age 12.4 y; 61.8% male; 70.6% single ventricle, 17.7% heart failure, and 11.8% pulmonary hypertension) and controls without HD (n = 22; median age 12.3 y; 59.1% male). Mean counts per minute were classified as sedentary, light, and moderate to vigorous PA (MVPA), and bouts of MVPA were calculated. PA was calculated separately for each hour of wear time from 8:00 to 22:00. Multilevel linear mixed modeling compared the outcomes, stratifying by group, time of day, and day part (presented as median percentage of valid wear time [interquartile range]).

RESULTS

Compared with the controls, the HD group had more light PA (33.9% [15%] vs 29.6% [9.5%]), less MVPA (1.7% [2.5%] vs 3.2% [3.3%]), and more sporadic bouts (97.4% [5.7%] vs 89.9% [9.2%]), but fewer short (2.0% [3.9%] vs 7.1% [5.7%]) and medium-to-long bouts (0.0% [1.9%] vs 1.6% [4.6%]) of MVPA. The HD group was less active in the late afternoon, between 15:00 and 17:00 (P < .03). There were no differences between groups in sedentary time.

CONCLUSION

Children/adolescents with HD exhibit differences in intensity-specific volumes, PA bouts, and daily PA patterns compared with controls.

Contributions of residual hypoxemia to exercise hyperventilation in Fontan patients

It is unsettled whether increased exercise ventilation in Fontan subjects is due to increased pulmonary dead space or augmented ventilatory drive. Twenty-six Fontan patients underwent symptom-limited treadmill cardiopulmonary exercise testing. Two groups of age- and sex- matched subjects served as controls: the biventricularly repaired (Bi, n = 18), and the "true" control (C, n = 29) groups. Peak oxygen uptake (V̇O_2peak) was not different among groups (41.0 +/- 8.4 ml/min/kg, 43.5 +/- 6.6 ml/min/kg, and 45.9 +/- 11.6 ml/min/kg for Fontan, Bi, and C groups, respectively, p = 0.16). Fontan subjects, however, showed steeper alveolar ventilation/carbon-dioxide (V̇A/V̇CO₂) regression slope (35.5 +/- 5.3, 28.7 +/- 3.8, and 29.5 +/- 3.0 l/ml, for Fontan, Bi, and C groups, respectively, p<0.0001), and lower end-expiratory carbon-dioxide fraction (FetCO_2VAT) at ventilatory threshold (VAT) (4.4 +/- 0.5%, 5.5 +/- 0.5%, and 5.5 +/- 0.4%, for Fontan, Bi, and C groups, respectively, p<0.001). The dead-space ventilation fraction at VAT was similar among groups (0.33 +/- 0.06, 0.33 +/- 0.04, 0.35 +/- 0.05 for Fontan, Bi, and C groups, respectively, p = 0.54). In Fontan subjects, arterial oxygen saturation at rest (SaO_2rest) was correlated with V̇A/V̇CO₂ regression slope (r = -0.41, p = 0.04) and with FetCO_2VAT (p = -0.53, p<0.01). We conclude that Fontan patients show exercise hyperventilation due to augmented central and/or peripheral ventilatory drive, which is further augmented by residual hypoxemia.

Evaluation of Physical Fitness in Children With Congenital Heart Diseases Versus Healthy Population

We aimed to evaluate and compare the physical fitness of children with different severity of the cardiac defect with their healthy peers. We included 182 children after cooperation for congenital heart disease (CHD) and 129 healthy children as controls, 6-18 years old, who performed a complete cardiopulmonary exercise test (CPET) in a cross-sectional observational study. The CHD patients were further subdivided into three subgroups according to diagnostic characteristics and surgical methods: simple CHD group (SCHD), complex CHD group (CCHD)and total cavopulmonary connection group (TCPC). Physical fitness was compared between groups using generalized linear model and multiple linear regression analysis. In comparison with age and gender adjusted healthy controls, children in SCHD, CCHD, and TCPC subgroups had accordingly graded down values of peak oxygen consumption (VO_2max: 44.86 ± 5.41 vs. 39.91 ± 5.59 vs. 36.95 ± 5.92 vs. 32.04 ± 5.38 mL/kg/min, P < 0.05) and %predicted VO_2max (1.01 ± 0.14 vs. 0.91 ± 0.13 vs. 0.83 ± 0.15 vs. 0.72 ± 0.13, P < 0.05) for each group. The proportion of %predicted VO_2max above 80% in the CHD and the control group were 60.4% and 96.1% (P < 0.001). The VO_2max decreased by 0.98 mL/kg/min per year in CHD children, and the corresponding %predicted reference diminished by 2.0%. Children with TCPC had the highest mean decrease of VO_2max and %predicted VO_2max per year of age (1.23 mL/kg/min, corresponding 3.0%). Although the mean overall physical fitness of children with simple and complex defect after biventricular correction were significantly different from healthy population, they were close to normal (>80%predicted VO_2max). However, TCPC group had much lower exercise capacity.

Appropriate heart rate during exercise in Fontan patients

OBJECTIVE

To evaluate heart rate against workload and oxygen consumption during exercise in Fontan patients.

METHOD

Fontan patients (n = 27) and healthy controls (n = 25) underwent cardiopulmonary exercise testing with linear increase of load. Heart rate and oxygen uptake were measured during tests. Heart rate recovery was recorded for 10 minutes.

RESULTS

Heart rate at midpoint (140 ± 14 versus 153 ± 11, p < 0.001) and at maximal effort (171 ± 14 versus 191 ± 10 beats per minute, p < 0.001) of test was lower for patients than controls. Heart rate recovery was similar between groups. Heart rate in relation to workload was higher for patients than controls both at midpoint and maximal effort. Heart rate in relation to oxygen uptake was similar between groups throughout test. Oxygen pulse, an indirect surrogate measure of stroke volume, was reduced at maximal effort in patients compared to controls (6.6 ± 1.1 versus 7.5 ± 1.4 ml·beat-1·m-2, p < 0.05) and increased significantly less from midpoint to maximal effort for patients than controls (p < 0.05).

CONCLUSIONS

Heart rate is increased in relation to workload in Fontan patients compared with controls. At higher loads, Fontan patients seem to have reduced heart rate and smaller increase in oxygen pulse, which may be explained by inability to further increase stroke volume and cardiac output. Reduced ability to increase or maintain stroke volume at higher heart rates may be an important limiting factor for maximal cardiac output, oxygen uptake, and physical performance.

Health-Related Quality of Life in Children, Adolescents, and Adults With a Fontan Circulation: A Meta-Analysis

Background

People with a Fontan circulation experience a range of physical, psychosocial and neurodevelopmental challenges alongside, or caused by, their cardiac condition, with significant consequences for health‐related quality of life (HRQOL). We meta‐analyzed HRQOL outcomes reported by people with a Fontan circulation or their proxies and evaluated predictors of poorer HRQOL.

Methods and Results

Six electronic databases were searched for peer‐reviewed, English‐language articles published before March 2019. Standardized mean differences (SMD) were calculated using fixed and random‐effects models. Fifty articles reporting on 29 unique studies capturing HRQOL outcomes for 2793 people with a Fontan circulation and 1437 parent‐proxies were analyzed. HRQOL was lower in individuals with a Fontan circulation compared with healthy referents or normative samples (SMD, −0.92; 95% CI, −1.36 to −0.48; P<0.001). Lower scores were reported across all HRQOL domains, with the largest differences found for physical (SMD, −0.90; 95% CI, −1.13 to −0.67; P<0.001) and school/work functioning (SMD, −0.71; 95% CI, −0.90 to −0.52; P<0.001). Meta‐regression analyses found no significant predictors of self‐reported physical functioning, but older age at Fontan operation was associated with poorer emotional functioning (β=−0.124; P=0.004), and diagnosis of hypoplastic left heart was associated with poorer social functioning (β=−0.007; P=0.048). Sensitivity analyses showed use of the PedsQL Core Module was associated with lower HRQOL scores compared with the Short‐Form Health Survey‐36.

Conclusions

HRQOL outcomes for people with a Fontan circulation are lower than the general population. Optimal care acknowledges the lifelong impact of the Fontan circulation on HRQOL and offers targeted strategies to improve outcomes for this growing population.

Impact of Sophrology on cardiopulmonary fitness in teenagers and young adults with a congenital heart disease: The SOPHROCARE study rationale, design and methods

Background

Recent advances in the field of congenital heart disease (CHD) have significantly improved the overall prognosis. Now more attention is being given to health-related quality of life (HRQoL) and promotion of physical activity. Non-invasive relaxation therapy may be effective in cardiac patients concerned with exercise-induced dyspnoea. The SOPHROCARE randomised trial aims to assess the impact of Caycedian Sophrology on cardiopulmonary fitness in adolescents and young adults with CHD.

Methods

The SOPHROCARE trial is a nationwide, multicentre, randomised, controlled study in CHD patients aged from 13 to 25 years old. Patients will be randomised into 2 groups (8 Sophrology group sessions vs. no intervention). The primary outcome is the change in percent predicted maximum oxygen uptake (VO2_max) between baseline and 12-month follow-up. A total of 94 patients in each group is required to observe a significant increase of 10% in VO2_max with a power of 80% and an alpha risk of 5%. The secondary outcomes are: clinical outcomes, cardiopulmonary exercise test parameters (VE/VCO2 slope, ventilatory anaerobic threshold, oxygen pulse, respiratory response to hypercapnia), health-related quality of life score (PedsQL), physical and psychological status.

Conclusion

After focusing on the survival in CHD, current research is opening on secondary prevention and patient-related outcomes. We sought to assess in the SOPHROCARE trial, if a Sophrology program, could improve exercise capacity and quality of life in youth with CHD.

Trial registration

Clinicaltrials.gov (NCT03999320).

Children with Congenital Heart Disease Are Active but Need to Keep Moving: A Cross-Sectional Study Using Wrist-Worn Physical Activity Trackers

OBJECTIVE

To compare daily physical activity of children with congenital heart disease (CHD) with healthy peers measured using wearables bracelets in a large cohort. Additionally, subjectively estimated and objectively measured physical activity was compared.

STUDY DESIGN

From September 2017 to May 2019, 162 children (11.8 ± 3.2 years; 60 girls) with various CHD participated in a self-estimated and wearable-based physical activity assessment. Step-count and moderate-to-vigorous physical activity were recorded with the Garmin vivofit jr. for 7 consecutive days and compared with a reference cohort (RC) of 96 healthy children (10.9 ± 3.8 years; 49 girls).

RESULTS

Children with CHD were active and 123 (75.9%) achieved 60 minutes physical activity on a weekly average according to the World Health Organization criteria as 81 (84.3%) of the healthy peers did (P = .217). After correction for age, sex, and seasonal effects, only slightly lower step count (CHD: 10 206 ± 3178 steps vs RC: 11 142 ± 3136 steps; P = .040) but no lower moderate-to-vigorous physical activity (CHD: 80.5 ± 25.6 minutes/day vs RC: 81.5 ± 25.3 minutes/day; P = .767) occurred comparing CHD with RC. In children with CHD higher age (P = .004), overweight or obesity (P = .016), complex severity (P = .046), and total cavopulmonary connection (P = .027) were associated with not meeting World Health Organization criteria. Subjective estimation of daily moderate-to-vigorous physical activity was fairly correct in half of all children with CHD.

CONCLUSIONS

Even though the majority is sufficiently active, physical activity needs to be promoted in overweight or obese patients, patients with complex CHD severity, and in particular in those with total cavopulmonary connection.

Physical activity and heart rate monitoring in Fontan patients - Should we recommend activities in higher intensities?

OBJECTIVE

Exercise capacity is impaired in Fontan palliated patients. The change in daily activity behaviour with an increase in sedentary lifestyle results in low physical activity levels. This might have a greater impact on patients with chronic heart disease in contrast to healthy controls. For a better understanding, we compared data from cardiopulmonary exercise testing (CPET) with heart rates and physical activity in daily life.

METHODS

21 Fontan patients and 20 age, sex and BMI matched controls underwent CPET and 5 days of daily life activity tracking with a triaxial accelerometer (wGT3x-BT, Actigraph) including heart rate monitoring with an optical heart rate sensor.

RESULTS

27% of our Fontan teenagers and 71% of the Fontan adults reached the specific WHO recommendations for moderate to vigorous physical activity (MVPA) during everyday life (EDL), without differences to controls. There was a strong correlation between MVPA and [Formula: see text] for all Fontan patients (p = 0.0035, Pearson r = 0.788). Daily MVPA correlated to peak oxygen uptake and lactate production. Up to workloads of 2 W/kg and in daily life heart rates in Fontan patients were similar to controls.

CONCLUSIONS

Daily MVPA is alarmingly low without any differences between Fontan patients and controls. Heart rate behaviour was similar and does not seem to be a limiting factor for physical activity in daily life. Higher intensity activities should be implemented regularly in EDL for Fontan patients. Proof is needed as to whether sports in moderate or possibly even in vigorous activity (e.g. high-intensity interval training) improve exercise capacity the most.

Imaging of complications following Fontan circulation in children - diagnosis and surveillance

The Fontan operation is performed for various cardiac lesions with single-ventricle physiology. The survival rate of Fontan patients is increasing for adolescents and young adults, with an expected 30-year survival of >80%. Medical health care providers including specialists in organ systems and pediatric radiologists need to improve their knowledge about the Fontan circulation and the various organ complications to monitor care. In this review the author explains the basic anatomical and functional features of Fontan palliation and gives an overview of the multiple long-term organ complications that might present in the pediatric population. These include decreased physical capacity, ventricular dysfunction, atrioventricular valve regurgitation and arrhythmia, as well as protein-losing enteropathy, plastic bronchitis, growth/bone composition disturbances, renal dysfunction, and the recently recognized and important liver fibrosis (Fontan-associated liver disease). Neuropsychological and behavioral deficits occur frequently. This review focuses on the key role of radiology in making the diagnosis of these complications, monitoring therapy and predicting outcomes in the pediatric age group. The author discusses how and when radiology is important in Fontan patients, as well as how new techniques enabling quantitative measures in imaging with US, MRI and CT are adapted for pediatric use, and how they contribute to urgently needed surveillance strategies.

Impact of Characteristics at Stage-2-Palliation on Outcome Following Fontan Completion

The optimal timing of stage-2-palliation (S2P) in single left ventricle is not clear. The aim of this study was to identify S2P related factors associated with outcomes after total cavopulmonary connection (TCPC), particularly relative to the dominant systemic ventricle. A total of 405 patients who underwent both S2P and TCPC at our institute between 1997 and 2017 was included. Patients were divided into two groups, dominant right ventricle (RV type, n = 235) and dominant left ventricle (LV type, n = 170). S2P related factors associated with mortality, postoperative ventricular function, and late exercise capacity following TCPC, were analyzed. The median age at S2P was 4 [3-7] and 6 [3-11] months in RV and LV type patients, respectively (p = 0.092). Survival after TCPC was similar in RV and LV type patients (p = 0.280). In those with RV type, risk factors for mortality following TCPC were older age (p < 0.001), heavier weight (p = 0.001), higher PAP (p < 0.001), higher TPG (p = 0.010), and lower SO2 (p = 0.008) at S2P. In those with LV type, no risk factor was identified. Risk factors for postoperative impaired ventricular function were older age and higher weight at S2P in both RV and LV type patients. Older age at S2P was also identified as a risk for inferior peak oxygen uptake (VO2) years after TCPC both in RV and LV type patients. Older age at S2P was associated with higher mortality after Fontan completion only in RV type patients. However, it was associated with postoperative ventricular dysfunction and lower exercise capacity after TCPC in both RV and LV type patients.

Differences in cerebral and muscle oxygenation patterns during exercise in children with univentricular heart after Fontan operation compared to healthy peers

BACKGROUND

We assess whether the lower exercise tolerance in children with univentricular heart (UVH) after Fontan operation is associated with altered peripheral muscular and cerebral tissue oxygenation.

METHODS

18 children with UVH and 20 healthy subjects performed an incremental ramp exercise test. Changes in the cerebral and muscular pattern of oxygenated (O₂Hb) and deoxygenated hemoglobin (HHb) and local tissue oxygenation (TOI) were analyzed by means of Near Infrared Spectroscopy (NIRS). Correlations between arterial saturation during exercise and tissue oxygenation were evaluated.

RESULTS

In UVH, maximal oxygen consumption (VO₂peak/kg, 28.9 ± 7.9 vs. 46.3 ± 11.9 ml/min/kg, P < 0.001), heart rate (HRpeak, 168 ± 13 vs. 193 ± 12 bpm, P < 0.001) and load (Ppeak, 73 ± 19 vs. 133 ± 68 W, P < 0.001) were lower, VE/VCO₂ slope was higher (34.5 ± 5.9 vs. 27.1 ± 3.9, P < 0.001). A faster and steeper course up to the same level of HHb and absent increase in O₂Hb was seen at cerebral level in UVH; tissue oxygenation index (TOI) demonstrated a steady decrease from the start of exercise. At the muscular level, HHb curve has a similar pattern compared to controls, with an early cessation. O₂Hb has a similar pattern, but with early discontinuation at a higher O₂Hb-level. Muscular TOI has the same course throughout exercise, starting from a lower level. Lower arterial saturation and higher age correlated with lower VO₂peak; higher amplitude of muscular TOI and lower amplitude cerebral TOI correlated with higher VO₂peak.

CONCLUSION

Children after Fontan procedure have different oxygenation mechanisms at muscular and cerebral level. This reflects a different balance between O₂ supply to O₂ demand which might contribute to the reduced exercise tolerance in this patient population.

Physical exercise may improve sleep quality in children and adolescents with Fontan circulation

OBJECTIVE

To study physical activity and sleep in Fontan patients and healthy controls before and after an endurance training program, and after 1 year.

METHOD

Fontan patients (n = 30) and healthy controls (n = 25) wore accelerometers for seven consecutive days and nights during a school week before and after a 12-week endurance training program and after 1 year.

RESULTS

Patients had similar sleep duration and sleep efficiency as healthy controls. Latency to sleep onset in minutes was longer for patients than controls (22.4 (4.3-55.3) minutes versus 14.8 (8.6-29.4) minutes, p < 0.01). More time in moderate-to-vigorous activity daytime was correlated with increased sleep time (p < 0.05; r2 = 0.20), improved sleep efficiency (p < 0.01; r2 = 0.24) and less time as wake after sleep onset (p < 0.05; r2 = 0.21) for patients but not controls. Sleep variables did not change after the exercise intervention for patients or controls. After 1 year, patients had decreased total sleep time, decreased sleep efficiency, increased accelerometer counts during sleep and more time as wake after sleep onset during sleep time, but not controls.

CONCLUSIONS

Fontan patients have prolonged latency to sleep onset compared with controls. More time in physical activities was correlated with better sleep quality for the patients. Also, subjects with low sleep efficiency and long latency to sleep onset may benefit most from physical exercise. These patients should be encouraged to engage in individually designed physical exercise as this could improve sleep quality.

Effects of Congenital Heart Disease Treatmenton Quality of Life

With rising survival rates of patients with congenital heart disease (CHD), functional health variables have become the key aspect in treatment evaluation. The effectiveness of various treatment options on the health-related quality of life (HRQoL) and the objectively measured exercise capacity as peak oxygen uptake (VO₂ peak) remains rather unclear and hence, its investigation is the primary aim of this study. Data from 1014 patients (≥14-years-old, various CHD) were retrospectively reviewed. The patients had completed at least twice the SF-36 questionnaire on HRQoL prior to a cardiopulmonary exercise test. Each patient was assigned to 1 of 4 treatment groups (i.e., surgery, catheter intervention, drug therapy, and surveillance) according to the received treatment between the baseline and the follow-up examination. After 4.0 ± 2.2 years of follow-up, patients with surgery and catheter intervention showed an increase in the physical summary score of HRQoL as compared to the other treatment groups (p <0.001). This effect remained also significant in a multivariable model accounting for anthropometric and baseline data. No significant differences in the mental summary score of HRQoL and the VO₂ peak were evident between the different treatment groups in the multivariable model. No significant correlation was found between the changes in HRQoL and VO₂ peak over time. In conclusion, despite insignificant changes in aerobic capacity, adolescents and adults with CHD report better physical HRQoL following surgery and catheter intervention compared to the other treatment options. HRQoL and exercise capacity need to be considered concurrently in the evaluation of adolescents and adults with CHD.

FUNCTIONAL CAPACITY IN CHILDREN AND ADOLESCENTS WITH CONGENITAL HEART DISEASE

Objective:

To evaluate the physical activity level and functional capacity of children and adolescents with congenital heart disease and to describe correlations between functionality, surgical and echocardiographic findings, metabolic and inflammatory profile and differences between acyanotic and cyanotic heart defects.

Methods:

A cross-sectional study including children and adolescents with congenital heart disease between six and 18 years old that were evaluated with the 6-minute walk test (6MWT) to assess functional capacity. The short version form of the International Physical Activity Questionnaire (IPAQ) was performed to evaluate physical activity levels. Also, echocardiography and blood collection, to evaluate the metabolic (blood glucose, lipids, insulin) and inflammatory markers (C-reactive protein), were assessed.

Results:

Twenty-five individuals were evaluated. Of them, 14 had acyanotic heart defects and 11 cyanotic heart defects. Mean age was 12.0±3.7 years, and 20 (80%) were male. IPAQ showed that six (24%) individuals were very active, eight (32%) were active, nine (36%) had irregular physical activity, and two (8%) were sedentary. The mean distance walked in the 6MWT, considering all studied individuals, was 464.7±100.4 m, which was 181.4±42.0 m less than the predicted (p=0.005). There was a positive correlation between Z score 6MWT and the number of surgical procedures (r=-0.455; p=0.022).

Conclusions:

Children and adolescents with congenital heart disease have low functional capacity, but they are not completely sedentary.

A restrictive ventilatory pattern is common in patients with univentricular heart after Fontan palliation and associated with a reduced exercise capacity and quality of life

AIM

The Fontan circulation is highly dependent on ventilation, improving pulmonary blood flow and cardiac output. A reduced ventilatory function is reported in these patients. The extent of this impairment and its relation to exercise capacity and quality of life is unknown and objective of this study.

METHODS

This multicenter retrospective/cross-sectional study included 232 patients (140 females, age 25.6 ± 10.8 years) after Fontan palliation (19.8% atrioventricular connection; 20.3% atriopulmonary connection; 59.9% total cavopulmonary connection). Resting spirometry, cardiopulmonary exercise tests, and quality-of-life assessment (SF-36 questionnaire) were performed between 2003 and 2015.

RESULTS

Overall, mean forced expiratory volume in one second (FEV₁ ) was 74.7 ± 17.8%predicted (%pred). In 59.5% of the patients, FEV₁ was <80%pred., and all of these patients had FEV₁ /forced vital capacity (FVC) > 80%, suggestive of a restrictive ventilatory pattern. Reduced FEV₁ was associated with a reduced peakVO₂ of 67.0 ± 17.6%pred. (r = 0.43, P < .0001), even if analyzed together with possible confounding factors (sex, BMI, age, years after palliation, number of interventions, scoliosis, diaphragmatic paralysis). Synergistically to exercise capacity, FEV₁ was associated to quality of life in terms of physical component summary (r = 0.30, P = .002), physical functioning (r = 0.25, P = .008), bodily pain (r = 0.22, P = .02), and general health (r = 0.16, P = .024). Lower FEV₁ was associated with diaphragmatic paralysis (P = .001), scoliosis (P = .001), higher number of interventions (P = .002), and lower BMI (P = .01). No correlation was found to ventricular morphology, type of surgeries, or other perioperative/long-term complications.

CONCLUSIONS

This study shows that the common restrictive ventilatory pattern in Fontan patients is associated with lower exercise capacity and quality of life. Risk factors are diaphragmatic paralysis, scoliosis, a high total number of interventions and low BMI.