Resistance training improves cardiac output, exercise capacity and tolerance to positive airway pressure in Fontan physiology

Competitive Sports Participation is Associated with Decreased Risk of Obesity in Children with Bicuspid Aortic Valve

Individuals with bicuspid aortic valve (BAV) have historically been advised to avoid contact sports and isometric exercise for risk of increasing aortic dilation and valve disease. There is mounting evidence that current sports participation guidelines qualify children for a high rate of sports exclusion, and that this population is at increased risk of obesity. The primary aim of this study was to evaluate relationship between sports participation and aortic dilation in children with bicuspid aortic valve and secondarily the relationship between competitive sports participation and obesity. We performed a review of children between the ages of 8 and 17 years with isolated BAV followed at Oregon Health & Science University. We excluded those with other congenital heart diseases, genetic conditions, prior cardiac intervention, and inability to ambulate independently. Parents completed a phone survey detailing their child's level of daily activity and participation in competitive sports. Demographic information and most recent echo findings were collected from the electronic medical record. We found no difference between the aortic diameters of athletes vs non-athletes. We also found that sports participation and daily activity were both associated with a decreased likelihood of obesity (OR 0.24, 95% CI 0.078-0.73 and OR 0.24, 95% CI 0.081-0.71 respectively). In summary, in our sample population, competitive sports participation was associated with a decreased risk of obesity. Competitive sports participation does not appear to be associated with an increased risk of aortic dilation in our population.

Percentage Predicted Peak Oxygen Consumption in People With Fontan Circulation: A Rapid Systematic Scoping Review and Validation Study

BACKGROUND

Peak oxygen consumption (peak V ̇ O 2 $$ \dot{\mathrm{V}}{\mathrm{O}}_2 $$ ) is routinely measured in people who have congenital heart disease and is reported as a percentage of predicted value, based upon age- and sex-matched normative reference values (NRVs). This study aimed to identify which NRVs are being used, assess whether NRVs are being applied appropriately, and evaluate if recommended NRVs are valid when applied to people with congenital heart disease.

METHODS AND RESULTS

A systematic scoping review identified studies that reported peak V ̇ O 2 $$ \dot{\mathrm{V}}{\mathrm{O}}_2 $$ percentage of predicted value in people with congenital heart disease. A modified risk of bias tool evaluated the included studies. Forty-five studies reported peak V ̇ O 2 $$ \dot{\mathrm{V}}{\mathrm{O}}_2 $$ percentage of predicted value, and only 21 (47%) studies described or provided a reference on how their percentage of predicted value was calculated. The most cited NRVs were from Wasserman (n=12) and Cooper and Weiler-Ravell (n=7). Risk of bias analysis judged 63% of studies as having some concerns. The NRVs recommended by the American Heart Association were applied to participants with a Fontan circulation (n=70; aged 26.5±6.4 years; 59% women) to examine validity. Predicted peak V ̇ O 2 $$ \dot{\mathrm{V}}{\mathrm{O}}_2 $$ values from the Wasserman NRV was not significantly associated to measured peak V ̇ O 2 $$ \dot{\mathrm{V}}{\mathrm{O}}_2 $$ values (men: b=0.31, R2≤0.01; women: b=0.07, R2=0.02).

CONCLUSIONS

Numerous NRVs have been applied to individuals with congenital heart disease and are often poorly reported and inappropriately matched to participants. The Wasserman NRV was the most cited but showed poor validity when applied to a Fontan cohort.

Pregnancy in patients with the Fontan operation

Improved survival rates for patients with a Fontan circulation has allowed more women with this complex cardiac physiology to contemplate pregnancy. However, pregnancy in women with a Fontan circulation is associated with a high risk of adverse maternal and foetal outcomes, high rates of miscarriage, and preterm delivery. Factors associated with a successful pregnancy outcome are younger age, normal body weight, absence of significant functional limitation, no Fontan-related complications, and well-functioning single ventricle physiology. Appropriate care with timely preconception counselling and regular, frequent clinical reviews by a multidisciplinary team based at a tertiary centre improves the chance of a successful pregnancy. Empowerment of patients with education on their specific congenital cardiac condition and its projected trajectory helps them make informed choices regarding their health, reproductive choices, and assists them to achieve their life goals.

The effect of multi-component exercise on cognition function in patients with diabetes: A systematic review and meta-analysis

BACKGROUND

This meta-analysis investigated the influence of exercise on cognitive function in people living with diabetes.

METHODS

Stringent criteria for literature inclusion and exclusion were defined. Searches were conducted across four English databases to gather randomized controlled trials investigating exercise interventions for cognitive function in people living with diabetes. Outcome indicators from 1193 subjects across 12 articles were analyzed using RevMan 5.4 software.

RESULTS

Exercise intervention demonstrated the ability to mitigate cognitive decline in people living with diabetes, with a combined effect size (standardized mean difference) of 0.91, 95% CI: 0.28, 1.54, P < 0.00001. The intervention effect showed significant modulation by intervention content (I2 = 95%), intervention duration (I2 = 95%), intervention frequency (I2 = 95%), and intervention cycle (I2 = 96%). Among these factors, multi-component exercise, sessions >40 minutes, exercise frequency >4 times per week, and sustained exercise for >6 months were paramount, all with P < 0.05.

CONCLUSION

Exercise intervention emerges as a viable strategy for delaying cognitive decline in people living with diabetes. Its efficacy is subject to modulation by various variables. Optimal intervention includes multi-component exercise, individual sessions lasting 40-60 minutes, exercising >4 times a week, and continuous exercise for over 6 months.

The effects of telerehabilitation in adults with complex biventricular congenital heart conditions: protocol for a multi-centre, randomised controlled trial-CH-FIT

BACKGROUND

Accumulated evidence suggests that exercise training exerts beneficial effects on people with congenital heart conditions. These findings are predominantly derived from small, single-centre exercise trials conducted in outpatient rehabilitation facilities. In recent years, the delivery of exercise interventions remotely has increased through digital communications technology (telerehabilitation). However, very little research to date has been conducted into the efficacy of telerehabilitation in people with a congenital heart condition.

AIMS

To evaluate the effects of a telehealth-delivered exercise intervention in people with a history of a surgical biventricular repair due to a congenital heart condition.

METHODS

One hundred eligible adolescent (≥ 16 years) and adult participants living with a complex biventricular congenital heart condition will be recruited from four Australian sites and randomised to either (1) a 16-week telehealth-delivered combined (aerobic and resistance) exercise training programme of moderate-to-vigorous intensity or (2) usual care (control group), in a 1:1 allocation, with an 8-month follow-up.

OUTCOMES OF INTEREST

The primary outcome will be the change in aerobic capacity expressed as peak oxygen uptake (VO2peak). Secondary outcomes will include changes in vascular function, muscle oxygenation, metabolic profile, body composition and musculoskeletal fitness, neurohormonal activation, neurocognitive function, physical activity levels, dietary and nutritional status, and quality of life. Outcomes will be assessed at baseline, 16 weeks, and 12 months (to determine longer-term maintenance potential).

DISCUSSION

If found to be efficacious, telerehabilitation may be an alternative option for delivering exercise, improving health outcomes, and increasing accessibility to exercise programmes. Efficacy data is required to quantify the clinical significance of this delivery mode of exercise.

TRIAL REGISTRATION

ACTRN12622000050752 Trial registration date: 17 January 2022 Trial registration URL: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=382635&showOriginal=true&isReview=true Trial registry name: Australian and New Zealand Clinical Trials Registry.

Leg-focused high-weight resistance training improves ventricular stroke volume, exercise capacity and strength in young patients with a Fontan circulation

AIMS

Effective therapy to improve exercise capacity in Fontan patients is lacking. Leg-focused high-weight resistance training might augment the peripheral muscle pump and thereby improve exercise capacity.

METHODS AND RESULTS

This randomized semi-cross-over controlled trial investigated the effects of a 12-week leg-focused high-weight resistance training plus high-protein diet, on (sub)maximal exercise capacity, cardiac function (assessed with cardiovascular magnetic resonance), muscle strength, and quality of life in paediatric Fontan patients. Twenty-eight paediatric Fontan patients were included, 27 patients, (median age 12.9 [10.5-15.7]), and successfully completed the programme. Peak oxygen uptake (PeakVO2) at baseline was reduced [33.3 mL/kg/min (27.1-37.4), 73% (62-79) of predicted]. After training PeakVO2/kg and Peak workload improved significantly with +6.2 mL/kg/min (95%CI: 3.4-9.0) (+18%) P < 0.001 and +22 Watts (95%CI: 12-32) (+18%) P < 0.001, respectively, compared to the control period. Indexed single ventricle stroke volume increased significantly [43 mL/beat/m2 (40-49) vs. 46 (41-53), P = 0.014], as did inferior vena cava flow [21 mL/beat/m2 (18-24) vs. 23 (20-28), P = 0.015], while superior vena cava flow remained unchanged. The strength of all measured leg-muscles increased significantly compared to the control period. Self-reported quality of life improved on the physical functioning and change in health domains of the child health questionnaire, parent-reported quality of life improved the bodily pain, general health perception, and change in health domains compared to the control period.

CONCLUSION

In a relatively large group of 27 older Fontan children, 12-weeks of leg-focused high-weight resistance training improved exercise capacity, stroke volume, (sub)maximal exercise capacity, muscle strength, and domains of quality of life.

REGISTRATION

International Clinical Trials: Trial NL8181.

Resistance exercise lowers blood pressure and improves vascular endothelial function in individuals with elevated blood pressure or stage-1 hypertension

Lifestyle modifications are the first-line treatment recommendation for elevated blood pressure (BP) or stage-1 hypertension (E/S1H) and include resistance exercise training (RET). The purpose of the current study was to examine the effect of a 9-wk RET intervention in line with the current exercise guidelines for individuals with E/S1H on resting peripheral and central BP, vascular endothelial function, central arterial stiffness, autonomic function, and inflammation in middle-aged and older adults (MA/O) with untreated E/S1H. Twenty-six MA/O adults (54 ± 6 yr; 16 females/10 males) with E/S1H engaged in either 9 wk of 3 days/wk RET (n = 13) or a nonexercise control (Con; n = 13). Pre- and postintervention measures included peripheral and central systolic (SBP and cSBP) and diastolic BP (DBP and cDBP), flow-mediated dilation (FMD), carotid-femoral pulse wave velocity (cfPWV), cardiovagal baroreflex sensitivity (BRS), cardiac output (CO), total peripheral resistance (TPR), heart rate variability (HRV), and C-reactive protein (CRP). RET caused significant reductions in SBP {mean change ± 95% CI = [-7.9 (-12.1, -3.6) mmHg; P < 0.001]}, cSBP [6.8 (-10.8, -2.7) mmHg; P < 0.001)], DBP [4.8 (-10.3, -1.2) mmHg; P < 0.001], and cDBP [-5.1 (-8.9, -1.3) mmHg; P < 0.001]; increases in FMD [+2.37 (0.61, 4.14)%; P = 0.004] and CO [+1.21 (0.26, 2.15) L/min; P = 0.006]; and a reduction in TPR [-398 (-778, -19) mmHg·s/L; P = 0.028]. RET had no effect on cfPWV, BRS, HRV, or CRP relative to Con (P ≥ 0.20). These data suggest that RET reduces BP in MA/O adults with E/S1H alongside increased peripheral vascular function and decreased TPR without affecting cardiovagal function or central arterial stiffness.NEW & NOTEWORTHY This is among the first studies to investigate the effects of chronic resistance exercise training on blood pressure (BP) and putative BP regulating mechanisms in middle-aged and older adults with untreated elevated BP or stage-1 hypertension in a randomized, nonexercise-controlled trial. Nine weeks of resistance exercise training elicits 4- to 8-mmHg improvements in systolic and diastolic BP alongside improvements in vascular endothelial function and total peripheral resistance without influencing central arterial stiffness or cardiovagal function.

Stress imaging in patients with a Fontan circulation: A systematic review

INTRODUCTION

The aims of this study were to provide an overview of the cardiac stress response in Fontan patients and of the use, safety and clinical value of stress imaging in Fontan patients.

METHODS

Studies evaluating cardiac function using stress imaging in Fontan patients published up until 12 December 2021 were included in this review.

RESULTS

From 1603 potential studies, 32 studies met the inclusion criteria. In total, stress imaging tests of 728 Fontan patients were included. Cardiac function was most often measured using physical stress (61%), all other studies used dobutamine-induced stress. Stroke volume (SV) increased in most studies (71%), mean SV at rest ranged from 27 mL/m2 to 60 mL/m2 versus 27 mL/m2 to 101 mL/m2 during stress, and increased with an average of 4%. Ejection fraction increased in almost all studies, whereas both end-systolic volume and end-diastolic volume decreased during stress. Higher heart rates were obtained with physical stress (82-180) compared to dobutamine induced stress (73-128). Compared to controls, increases in heartrate and SV were lower and end-diastolic volume decreased abnormally in 75% of reporting studies. No major adverse events were reported. Poorer cardiac stress response was related to decreased exercise capacity and higher risk for long-term (adverse) outcomes in Fontan patients.

DISCUSSION

Cardiac stress response in Fontan patients differs from healthy subjects, reflected by lower increases in heart rate, diminished preload and decreased cardiac output, especially during higher levels of exercise. Stress imaging is safe, however the added clinical value needs to be investigated in more detail.

Home-Based Resistance Training Programme in Fontan Patients: It Is Feasible, Safe, and Efficient

Background

Fontan physiology is characterized by a single functional systemic ventricle that reduces cardiac output adaptation and exercise capacity. Peripheral muscle pump is crucial for venous return, and resistance training of the peripheral muscles may be particularly beneficial for cardiac function in these patients. This study explores the feasibility of a training programme including safety and effectiveness, maximal exercise capacity, cardiorespiratory endurance, and quality of life in a Fontan population.

Methods

Twelve Fontan patients (18-32 years old) with New York Heart Association functional classes I and II were recruited. The intervention was 12 weeks of home-based exercise programme of 3 sessions per week supervised online by a physiotherapist. Pre- and postintervention evaluations assessed lean body mass, segmental forces with a hand-held dynamometer, maximal oxygen consumption (VO2max), cardiovascular endurance, leg endurance with a 1-minute-sit-to-stand test, and quality of life with a 36-item Short-Form Survey.

Results

A total of 11 of 12 participants completed 35 of 36 workouts, exceeding our 80% threshold for completion. No adverse events were reported. Leg muscle strength increased significantly (knee extensors improved by 22.8 ± 22.8 N m [17.7%], P = 0.019). Despite no change in VO2max, endurance time showed a significant improvement of 5.3 minutes (72%). Perceived physical condition evaluated with a self-perception scale improved significantly. There was no significant difference in the lean body mass and in quality of life.

Conclusion

In this small group of post-Fontan patients with mild functional impairments, we describe a structured, accessible, and feasible home-based resistance training programme that seems safe and show improvements in strength and perceived physical condition.

Clinical and invasively-measured predictors of high exercise capacity in Fontan patients

INTRODUCTION

Fontan patients have variable exercise capacity. Contemporary understanding as to which factors predict high tolerance is limited.

METHODS

Records from the Ahmanson/University of California, Los Angeles Adult Congenital Heart Disease Center were reviewed for adult Fontan patients who underwent CPET. Patients were considered "high performers" if their maximum oxygen uptake (VO2 max/kg)-predicted was greater than 80%. Cross-sectional clinical, hemodynamic, and liver biopsy data was gathered. High-performers were compared to control patients across these parameters via associations and regression.

RESULTS

A total of 195 adult patients were included; 27 patients were considered "high performers". They had lower body mass indices (BMI, p < 0.001), mean Fontan pressures (p = 0.026), and cardiac outputs (p = 0.013). High performers also had higher activity levels (p < 0.001), serum albumin levels (p = 0.003), non-invasive and invasive systemic arterial oxygen saturations (p < 0.001 and p = 0.004), lower New York Heart Association (NYHA) heart failure class (p = 0.002), and were younger at Fontan completion (p = 0.011). High performers had less severe liver fibrosis (p = 0.015). Simple regression found Fontan pressure, non-invasive O2 saturation, albumin level, activity level, age at Fontan surgery, NYHA class, and BMI to predict significant changes in VO2 max/kg %-predicted. These associations persisted in multiple regression for non-invasive O2 saturation, NYHA class II, activity level, and BMI.

CONCLUSIONS

Thin Fontan patients who exercise more had better exercise capacity, Fontan hemodynamic profiles, and less liver fibrosis.

Five decades of Fontan palliation: What have we learned? What should we expect?

The Fontan procedure is the final palliative surgery in a series of staged surgeries to reroute the systemic venous blood flow directly to the lungs, with the ventricle(s) pumping oxygenated blood to the body. Advances in medical and surgical techniques have improved patients' overall survival after the Fontan procedure. However, Fontan-associated chronic comorbidities are common. In addition to chronic cardiac dysfunction and arrhythmias, complications involving other organs such as the liver, lungs, intestine, lymphatic system, brain, and blood frequently occur. This narrative review focuses on the immediate and late consequences in children, pregnant women, and other adults with Fontan circulation. In addition, we describe the technical advancements that might change the way single-ventricle patients are managed in future.

Effect of functional resistance training on the structure and function of the heart and liver in patients with non-alcoholic fatty liver

The current study is of the quasi-experimental type, with a pre-and post-test design, and subjects were randomly assigned to one of two groups: control (n = 8) and experimental (test) (n = 8). Based on the patient's self-report and using daily diet control tables, the patient's diet planning percentage of energy supply was managed and controlled for 3 days. The protocol for functional resistance training for these circular exercises, including the squat, lunge, bear crawl, rock press, jumping jack, and back fly lunge, was performed three times per week without specialized apparatus. Ejection fraction (EF) and fractional shortening (FS) were measured before and after functional resistance training, using echocardiography. Liver Stiffness and steatosis were measured using FibroScan, and the liver function was determined using biochemical assays. The average age of patients in the control group and the test group were 46.02 ± 5.4 and 48.6 ± 2.51, respectively. Pre-test and post-test of the body mass index were 32.06 ± 5.06 and 30.02 ± 3.97, and for the body fat percentage were 33.65 ± 6.09 and 25.41 ± 4.99. In non-alcoholic fatty liver patients, due to functional resistance training, EF (p-value = 0.003) and FS (p-value = 0.03) significantly increased, and C-reactive protein (Hs-CRP) (p-value = 0.001), steatosis (p-value = 0.04), and stiffness (p-value = 0.01) decreased. According to the results and without considering clinical trials, functional resistance training affects the structure and function of the heart and Liver in NAFLD patients.

Respiratory Muscle Function and Exercise Performance in Adult Patients with Fontan Circulation

At rest, a good Fontan circulation can provide a normal cardiac output (CO). However, as a consequence of its unique hemodynamic nature, the limitations of the Fontan circuit are exposed during exercise. We aimed to provide a comprehensive assessment of the pathophysiology of exercise in adult Fontan patients (FPs) and identify factors limiting their functional capacity (FC). In a single-center study conducted in 37 FPs aged ≥16 years and 19 healthy-controls (HCs) who underwent CPET on a cycle ergometer in February and March 2022, the mean peakVO₂ was 21 ± 5.4 mL/kg/min, which was 55% of the predicted value. Morphologically, the left single ventricle showed a higher peakVO₂% predicted value (57.4 ± 14.4% vs. 43.4 ± 8.1%, p = 0.045). The factors associated with low peakVO₂ values were an early flattened or descending O₂ pulse at maximal exertion (52 ± 14% vs. 62 ± 12.5, p = 0.04 and 47.6 ± 9% vs. 60 ± 14, p = 0.018, respectively) and chronotropic insufficiency (53 ± 12% vs. 69.8 ± 20%, p = 0.008). The OUES was found to be a useful parameter to assess the FC in FPs in maximal and submaximal exercise testing. A strong positive correlation was observed between the %OUES and peakVO₂%predicted (r = 0.726, p > 0.001). The lung function was impaired in the FPs, mostly with a mild restrictive pattern (56.8%). The FPs showed lower inspiratory muscle strength compared to the HCs but it was not statistically associated with either the peakVO₂ or VE/VCO₂ slope. Regular intense physical activity improves one's FC. Although FPs have inspiratory muscle weakness, its impact on their FC is unclear. The peakVO₂% predicted grew progressively higher as the level of physical activity increased (low level 49.5 ± 14%, moderate level 55 ± 12%, intense level 69 ± 20%).

Exercise Pathophysiology and Testing in Individuals With a Fontan Circulation

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

Design and rationale of re-energize fontan: Randomized exercise intervention designed to maximize fitness in fontan patients

In this manuscript, we describe the design and rationale of a randomized controlled trial in pediatric Fontan patients to test the hypothesis that a live-video-supervised exercise (aerobic+resistance) intervention will improve cardiac and physical capacity; muscle mass, strength, and function; and endothelial function. Survival of children with single ventricles beyond the neonatal period has increased dramatically with the staged Fontan palliation. Yet, long-term morbidity remains high. By age 40, 50% of Fontan patients will have died or undergone heart transplantation. Factors that contribute to onset and progression of heart failure in Fontan patients remain incompletely understood. However, it is established that Fontan patients have poor exercise capacity which is associated with a greater risk of morbidity and mortality. Furthermore, decreased muscle mass, abnormal muscle function, and endothelial dysfunction in this patient population is known to contribute to disease progression. In adult patients with 2 ventricles and heart failure, reduced exercise capacity, muscle mass, and muscle strength are powerful predictors of poor outcomes, and exercise interventions can not only improve exercise capacity and muscle mass, but also reverse endothelial dysfunction. Despite these known benefits of exercise, pediatric Fontan patients do not exercise routinely due to their chronic condition, perceived restrictions to exercise, and parental overprotection. Limited exercise interventions in children with congenital heart disease have demonstrated that exercise is safe and effective; however, these studies have been conducted in small, heterogeneous groups, and most had few Fontan patients. Critically, adherence is a major limitation in pediatric exercise interventions delivered on-site, with adherence rates as low as 10%, due to distance from site, transportation difficulties, and missed school or workdays. To overcome these challenges, we utilize live-video conferencing to deliver the supervised exercise sessions. Our multidisciplinary team of experts will assess the effectiveness of a live-video-supervised exercise intervention, rigorously designed to maximize adherence, and improve key and novel measures of health in pediatric Fontan patients associated with poor long-term outcomes. Our ultimate goal is the translation of this model to clinical application as an "exercise prescription" to intervene early in pediatric Fontan patients and decrease long-term morbidity and mortality.

Surrogates of Muscle Mass on Cardiac MRI Correlate with Exercise Capacity in Patients with Fontan Circulation

BACKGROUND

Sarcopenia is an increasingly recognized marker of frailty in cardiac patients. Patients with a history of congenital heart disease and Fontan procedure have a higher risk of developing progressive muscle wasting. Our objective was to determine if we could use routine cardiac MRI (CMR) for the surveillance of muscle wasting.

METHODS

A retrospective study of all Fontan patients (n = 75) was conducted at our institution, with CMR performed from 2010 to 2022 and exercise stress testing performed within 12 months (4.3 ± 4.2 months). The skeletal muscle area (SMA) for the posterior paraspinal and anterior thoracic muscles were traced and indexed for body surface area (BSA). Patients were stratified by percentile into the upper and lower quartiles, and the two groups were compared. Multivariable regression was performed to control for sex and age.

RESULTS

There was a significant positive association of both anterior (r = 0.34, p = 0.039) and paraspinal (r = 0.43, p = 0.007) SMA to peak VO2. Similarly, paraspinal but not anterior SMA was negatively associated with the VE/VCO2 (r = -0.45, p = 0.006). The upper quartile group had significantly more males (18/19 vs. 8/20; p = 0.0003) and demonstrated a significantly higher peak VO2 (32.2 ± 8.5 vs. 23.8 ± 4.7, p = 0.009), a higher peak RER (1.2 ± 0.1 vs. 1.1 ± 0.04, p = 0.007), and a significantly lower VE/VCO2 (32.9 ± 3.6 vs. 40.2 ± 6.2, p = 0.006) compared to the lowest quartile. The association of SMA to VO2 peak and VE/VCO2 was redemonstrated after controlling for sex and age.

CONCLUSION

Thoracic skeletal muscle area may be an effective surrogate of muscle mass and is correlated to several measures of cardiorespiratory fitness post-Fontan. CMR would be an effective tool for the surveillance of sarcopenia in post-Fontan patients given its accessibility and routine use in these patients.

Effect of weight-bearing Liuzijue Qigong on cardiopulmonary function

BACKGROUND

Since the outbreak of coronavirus disease 2019, many people have had to reduce their outdoor activities. Therefore, a convenient, simple, at-home training method to improve or maintain cardiopulmonary function is required. This study aimed to explore the therapeutic effect of weight-bearing Liuzijue Qigong on cardiopulmonary function in healthy volunteers.

METHODS

This study was a longitudinal trial. The health participants completed a 4-week Liuzijue Qigong exercise with 0.25 kg sandbag wore on each wrist. Each training session took 30 minutes to complete 2 consecutive cycles, and 5 times a week. The cardiopulmonary function of participants was evaluated at baseline (T0) and the end of the intervention (T4). Outcomes measures were pulmonary function, diaphragm movement, and cardiac hemodynamic parameters. Paired t test was used to analyze differences within the group.

RESULTS

After 4 weeks of weight-bearing Liuzijue Qigong exercise intervention, the differences in the forced expiratory volume in the 1st second (P = .006), forced vital capacity rate of 1 second (P = .003), maximal mid-expiratory flow curve (P = .002), forced expiratory flow at 50% of forced vital capacity (P = .003), and maximum ventilatory volume (P < .001) of the participants were statistically significant. The diaphragmatic excursion (P = .009) under the calm breathing mode and the diaphragmatic contraction speed (P = .003) under the deep breathing mode improved significantly. The cardiac output (P = .04), cardiac index (P = .035), contractility index (P = .018), early diastolic filling ratio (P = .042), systemic vascular resistance index (P = .019), systemic vascular resistance (P = .017), and estimated ejection fraction (P = .016) of participants improved significantly in the resting stage. At the end stage of fast walking, that is, the sixth minute of six-minute walk test, the stroke volume index (P = .048), heart rate (P = .019), cardiac output (P = .008), cardiac index (P = .003), and left cardiac work index (P = .028) of participants were significantly increased compared with those before training, and the systemic vascular resistance index (P = .003) and systemic vascular resistance (P = .005) were decreased.

CONCLUSION

Weight-bearing Liuzijue Qigong training significantly improved cardiopulmonary function in healthy volunteers, thus representing home-based cardiopulmonary rehabilitation training.

Exercise as therapy for neurodevelopmental and cognitive dysfunction in people with a Fontan circulation: A narrative review

People with a Fontan circulation are at risk of neurodevelopmental delay and disability, and cognitive dysfunction, that has significant implications for academic and occupational attainment, psychosocial functioning, and overall quality of life. Interventions for improving these outcomes are lacking. This review article discusses current intervention practices and explores the evidence supporting exercise as a potential intervention for improving cognitive functioning in people living with a Fontan circulation. Proposed pathophysiological mechanisms underpinning these associations are discussed in the context of Fontan physiology and avenues for future research are recommended.

Peak Work Rate Increases With Lower Extremity-Focused Exercise Training in Adolescents With Fontan Circulation

Background Skeletal muscle deficits are associated with worse exercise performance in the Fontan circulation and may be improved by exercise training. We aimed to assess the change in leg lean mass (a marker of skeletal muscle), exercise performance, and functional health status after a lower extremity-focused exercise intervention in adolescents with Fontan circulation. Methods and Results Densitometry for measurement of leg lean mass, cardiopulmonary exercise test, exercise cardiac magnetic resonance, peripheral vascular testing, physical activity questionnaire, and quality of life assessment were performed at baseline and after a 24-week, hybrid center- and home-based training program. Leg lean mass Z-scores were generated, and exercise parameters were expressed as percentage expected based on reference data. The effect of training was assessed by paired t-tests and simple linear regression. Twenty participants (15.6±1.7 years, 50% male) demonstrated low baseline leg lean mass Z-scores with no significant improvement with training (-1.38±1.02 pre versus -1.31±1.06 post, P=0.33). Maximum and percent predicted work increased from 121.9±29.8 (0.66±0.12) to 131.3±35.1 (0.70±0.15) watts (P=0.02). Peak respiratory exchange ratio increased (1.19±0.02 versus 1.25±0.01, P=0.02) but percent predicted oxygen consumption was unchanged, suggesting higher anaerobic activity after training. Physical activity questionnaire score positively associated with peak work at baseline (ß=18.13 [95% CI, 0.83-35.44], R²=0.21; P=0.04) but physical activity questionnaire, quality of life scores, exercise cardiac magnetic resonance performance, and peripheral vascular function were unchanged with training. Conclusions Peak work rate and anaerobic activity increased with lower extremity-focused training in adolescents with Fontan circulation. Larger studies should test the impact of these changes on functional status and quality of life.

Safety and efficacy of exercise training in children and adolescents with congenital heart disease: A systematic review and descriptive analysis

BACKGROUND

While exercise training is beneficial in the prevention and management of many chronic diseases, the role of exercise training in children and adolescents with congenital heart disease is less understood. We sought to determine the safety and efficacy of exercise training in children and adolescents with congenital heart disease.

METHODS

We conducted a systematic search of the following databases: PubMed, CINAHL, EMBASE, Web of Science and SportDiscus. We included randomised controlled trials that incorporated an exercise intervention compared with a non-exercising comparator group and examined safety and efficacy in children and adolescents with congenital heart disease. A descriptive analysis of the included trials was then conducted.

RESULTS

A total of 9 articles from 6 trials (642 participants with varying conditions and disease severity) were included. Significant variability of study participants and outcomes were observed across the trials. No adverse events linked to the exercise interventions were stated. The articles reported numerous positive changes to clinically relevant fitness measures. Exercise capacity improved with exercise training in 3 of 4 trials in which it was measured. Cardiorespiratory fitness showed improvements in 3 of 4 trials. Neuromuscular fitness increased in 1 of 2 trials. Physiological and metabolic parameters were improved, and negative changes were not observed to several clinically important measures (e.g. muscular oxygenation, cardiac measures) in 2 of 2 trials. Physical activity increased in 1 of 3 trials. No articles reported on changes in measures of body composition. Outcomes are varied with little consensus on measurements or assessment methods.

CONCLUSIONS

Exercise training appears to be safe and efficacious for improving physical fitness in children and adolescents with congenital heart disease who have been appropriately screened by their medical team. However, the certainty of the evidence for these findings is low to moderate.

Effects of 12-Week Home-based Resistance Training on Peripheral Muscle Oxygenation in Children With Congenital Heart Disease: A CHAMPS Study

Background

A hallmark feature of children with congenital heart disease (CHD) is exercise intolerance. Whether a home-based resistance training intervention improves muscle oxygenation (as measured by tissue oxygenation index, TOI) and exercise tolerance (V ˙ O2 reserve) during aerobic exercise in children with CHD compared with healthy children is unknown.

Methods

We report findings for 10 children with CHD (female/male: 4/6; mean ± standard deviation age: 13 ± 1 years) and 9 healthy controls (female/male: 5/4; age: 12 ± 3 years). Children with CHD completed a 12-week home-based exercise programme in addition to 6 in-person sessions. Exercise tolerance was assessed with a peak exercise test. Vastus lateralis TOI was continuously sampled during the peak V ˙ O2 test via near-infrared spectroscopy.

Results

There was a medium effect (Cohen's d = 0.67) of exercise training on lowering TOI at peak exercise (pre: 30 ± 16 %total labile signal vs post: 20 ± 13 % total labile signal; P = 0.099). Exercise training had a small effect (Cohen's d = 0.23) on increasing V ˙ O2 reserve by 1.6 mL/kg/min (pre: 27.2 ± 5.7 mL/kg/min vs post: 29.4 ± 8.8 mL/kg/min; P = 0.382). There was also a small effect (Cohen's d = 0.27) of exercise on peak heart rate (pre: 175 ± 23 beats/min vs post: 169 ± 21 beats/min; P = 0.18). TOI, V ˙ O2 reserve, and heart rate were generally lower than healthy control participants.

Conclusions

Our findings indicate that home-based resistance training may enhance skeletal muscle oxygen extraction (lower TOI) and subsequently V ˙ O2 reserve in children with CHD.

Cardiac Concerns in the Pediatric Athlete

Cardiovascular disease remains the number one cause of death in Americans. It is no secret that exercise mitigates this risk. Exercise and regular physical activity are beneficial for physical health including aerobic conditioning, endurance, strength, mental health, and overall improved quality of life. Unfortunately, today many children and adolescents are sedentary, lacking the recommended daily amount of physical activity, leading to higher rates of obesity, cardiovascular disease, stroke, diabetes, anxiety, and depression. Given this rising concern, the World Health Organization launched a 12-year plan to improve physical activity in children and adolescents by reducing the inactivity rate by 15% in the world. How does this apply to children and adolescents with acquired or congenital heart disease?.

Sports participation, activity, and obesity in children who have undergone the Fontan procedure

BACKGROUND

Children with CHD are at risk for obesity and low levels of activity. These factors are associated with an increased risk of poor outcome. Participation in organised sports is an important avenue for children to maintain physical activity, though the relationship between sports participation and obesity has not been examined in the Fontan population.

METHODS

We performed a cross-sectional study of children aged 8-18 who had been evaluated between January 1, 2015 and October 1, 2019 at the Doernbecher Children's Hospital outpatient paediatric cardiology clinic and had previously undergone a Fontan. Patients were excluded if they were unable to ambulate independently or if they had undergone a heart transplant. Patient characteristics were recorded from the electronic medical record. Parents were interviewed via a telephone survey and asked to describe their child's activity levels and sports participation.

RESULTS

Our final cohort included 40 individuals, 74% were male. The overall prevalence of obesity (CDC BMI >95% for sex/age) in the cohort (23%) was significantly higher in non-athletes (33%) than athletes (0) (p = 0.02). There was no difference in cardiac complications or comorbidities between athletes and non-athletes. Athletes were more likely to meet daily activity recommendations (p = 0.05).

CONCLUSION

Fontan patients who do not participate in sports are significantly more likely to be obese and less likely to be active than those who do. This is the first study to demonstrate the association between competitive sports participation and decreased likelihood of obesity in the Fontan population.

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 training in paediatric congenital heart disease: fit for purpose?

Exercise and physical activity (PA) have been shown to be effective, safe and feasible in both healthy children and children with congenital heart disease (CHD). However, implementing exercise training as an intervention is still not routine in children with CHD despite considerable evidence of health benefits and well-being. Understanding how children with CHD can safely participate in exercise can boost participation in PA and subsequently reduce inactivity-related diseases. Home-based exercise intervention, with the use of personal wearable activity trackers, and high-intensity interval training have been beneficial in adults' cardiac rehabilitation programmes. However, these remain underutilised in paediatric care. Therefore, the aims of this narrative review were to synthesise prescribed exercise interventions in children with CHD, identify possible limitation to exercise training prescription and provide an overview on how to best integrate exercise intervention effectively for this population into daily practice.

Vitamin D, liver-related biomarkers, and distribution of fat and lean mass in young patients with Fontan circulation

INTRODUCTION/AIM

Young patients with Fontan circulation may have low serum 25-hydroxyvitamin D levels, an affected liver, and unhealthy body compositions. This study aimed to explore the association between vitamin D intake/levels, liver biomarkers, and body composition in young Fontan patients.

METHOD

We collected prospective data in 2017 to 2018, obtained with food-frequency questionnaires, biochemical analyses of liver biomarkers, and dual-energy X-ray absorptiometry scans in 44 children with Fontan circulation. Body compositions were compared to matched controls (n = 38). Linear regression analyses were used to investigate associations of biomarkers, leg pain, and lean mass on serum levels of 25-hydroxyvitamin D. Biomarkers were converted to z scores and differences were evaluated within the Fontan patients.

RESULTS

Our Fontan patients had a daily mean vitamin D intake of 9.9 µg and a mean serum 25-hydroxyvitamin D of 56 nmol/L. These factors were not associated with fat or lean mass, leg pain, or biomarkers of liver status. The Fontan patients had significantly less lean mass, but higher fat mass than controls. Male adolescents with Fontan circulation had a greater mean abdominal fat mass than male controls and higher cholesterol levels than females with Fontan circulation.

CONCLUSION

Vitamin D intake and serum levels were not associated with body composition or liver biomarkers in the Fontan group, but the Fontan group had lower lean mass and higher fat mass than controls. The more pronounced abdominal fat mass in male adolescents with Fontan circulation might increase metabolic risks later in life.

The Effects of Exercise Training on Cardiopulmonary Exercise Testing and Cardiac Biomarkers in Adult Patients with Hypoplastic Left Heart Syndrome and Fontan Circulation

Background: Several studies have shown that adult patients with Hypoplastic Left Heart Syndrome (HLHS) and Fontan circulation have a reduced exercise tolerance that affects daily life. Recent studies have investigated the effects of aerobic exercise training in patients with univentricular heart; however, this research topic is still poorly studied. The aim of this study was to evaluate the effects of an aerobic exercise training program on cardiopulmonary exercise testing parameters and cardiac biomarkers in patients with HLHS. Methods: We enrolled 12 patients with a mean age of 24 ± 2.5 years (range 22−27 years), 50% male, with HLHS at Bambino Gesù Children’s Hospital IRCCS. All patients underwent a cardiopulmonary test and blood sampling before (T0) and after (T1) a 4-week aerobic exercise program. Cardiac biomarkers hs-cTnT, NT-proBNP, ST2, GDF-15 were studied. Results: Data analysis demonstrated an increase in cardiorespiratory performance after 4 weeks of aerobic exercise training activity. In particular, the data showed a significant improvement in test duration (p < 0.05), heart rate at rest (p < 0.05), heart rate recovery 1 min (p < 0.05), VO2 max (p < 0.01) and oxygen uptake efficiency slope (p < 0.05). At the same time, the data showed a significant reduction in NT-proBNP and ST2 values (p < 0.01 and p < 0.05, respectively) and a significant increase in GDF-15 (p < 0.01). No significant changes were found between the hs-cTnT values. Conclusions: Our study demonstrated the 4-week efficacy of an aerobic training program in improving cardiorespiratory performance and cardiac biomarker values in adult patients with HLHS and Fontan circulation. More studies with larger numbers of patients will be needed to confirm these data.

Fontan Circulation Associated Organ Abnormalities Beyond the Heart, Lungs, Liver, and Gut: A Systematic Review

Introduction

Patients with a Fontan circulation are at risk for sequelae of Fontan physiology during follow-up. Fontan physiology affects all organ systems and an overview of end-organ damage is needed.

Methods

We performed a systematic review of abnormalities in multiple organ systems for patients with a longstanding Fontan circulation. We searched online databases for articles describing abnormalities in multiple organ systems. Cardio-pulmonary abnormalities, protein losing enteropathy, and Fontan associated liver disease have already extensively been described and were excluded from this systematic review.

Results

Our search returned 5,704 unique articles. After screening, we found 111 articles relating to multiple organ systems. We found abnormalities in, among others, the nervous system, pituitary, kidneys, and musculoskeletal system. Pituitary edema—relating to the unique pituitary vasculature- may affect the thyroid axis. Renal dysfunction is common. Creatinine based renal function estimates may be inappropriate due to myopenia. Both lean muscle mass and bone mineral density are decreased. These abnormalities in multiple organ systems may be related to Fontan physiology, cyanosis, iatrogenic factors, or lifestyle.

Conclusions

Health care providers should be vigilant for hypothyroidism, visual or hearing deficits, and sleep disordered breathing in Fontan patients. We recommend including cystatin C for assessment of renal function. This review may aid health care providers and guide future research.

Systematic Review Registration:https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021232461, PROSPERO, identifier: CRD42021232461.

Molecular Mechanisms of Exercise and Healthspan

Healthspan is the period of our life without major debilitating diseases. In the modern world where unhealthy lifestyle choices and chronic diseases taper the healthspan, which lead to an enormous economic burden, finding ways to promote healthspan becomes a pressing goal of the scientific community. Exercise, one of humanity's most ancient and effective lifestyle interventions, appears to be at the center of the solution since it can both treat and prevent the occurrence of many chronic diseases. Here, we will review the current evidence and opinions about regular exercise promoting healthspan through enhancing the functionality of our organ systems and preventing diseases.

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.

Exercise Training for People Living with a Fontan Circulation: An Underutilized Intervention

Surgical repair for children born with single ventricle congenital heart disease, culminating in the Fontan operation, has resulted in dramatic improvements in survival; children born with these lesions are now typically expected to survive well into adulthood. Most, but not all, individuals with a Fontan circulation have reduced exercise capacity compared with the general population that in turn is associated with increased cardiovascular morbidity and mortality. The cause of reduced exercise capacity is multifactorial. A significant contributor is the absence of a subpulmonary ventricular pump, which limits preload and appropriate cardiac output augmentation to meet the increased metabolic demands that occur with exercise. While in its infancy relative to adults with acquired heart disease, the evidence to date suggests that exercise interventions to improve exercise capacity and Fontan physiology in children and adults with Fontan circulation are safe, effective and well tolerated. However, many knowledge gaps remain, including a detailed understanding of the unique physiological adaptations that occur, the optimal approach to exercise in this population and the effectiveness of home-based interventions utilizing telemedicine and remote physiologic monitoring technologies. Furthermore, the long-term impact of such interventions on the Fontan-cardiovascular system, physical activity levels, health-related quality of life, and late cardiovascular morbidity and mortality are not well characterized. In this review, we outline the factors associated with reduced exercise capacity in individuals with Fontan circulation, review the experience to date of dedicated interventions to improve exercise capacity, and highlight the current knowledge gaps in the field and priorities for further study.

Study Protocol of the Exercise Study: Unraveling Limitations for Physical Activity in Children With Chronic Diseases in Order to Target Them With Tailored Interventions-A Randomized Cross Over Trial

Introduction: Physical activity is associated with many physiological and psychological health benefits across the lifespan. Children with a chronic disease often have lower levels of daily physical activity, and a decreased exercise capacity compared to healthy peers. In order to learn more about limitations for physical activity, we investigate children with four different chronic diseases: children with a Fontan circulation, children with Broncho Pulmonary Dysplasia (BPD), Pompe disease and inflammatory bowel disease (IBD). Each of these diseases is likely to interfere with physical activity in a different way. Knowing the specific limitations for physical activity would make it possible to target these, and increase physical activity by a personalized intervention. The aim of this study is to first investigate limitations for physical activity in children with various chronic diseases. Secondly, to measure the effects of a tailored exercise intervention, possibly including a personalized dietary advice and/or psychological counseling, on exercise capacity, endurance, quality of life, fatigue, fear for exercise, safety, muscle strength, physical activity levels, energy balance, and body composition. Methods and Analysis: This randomized crossover trial will aim to include 72 children, aged 6-18 years, with one of the following diagnosis: a Fontan circulation, BPD, Pompe disease and IBD. Eligible patients will participate in the 12-week tailored exercise intervention and are either randomized to start with a control period or start with the intervention. The tailored 12-week exercise interventions, possibly including a personalized dietary advice and/or psychological counseling, will be designed based on the found limitations for physical activity in each disease group during baseline measurements by the Rotterdam Exercise Team. Effects of the tailored training interventions will be measured on the following endpoints: exercise capacity (measured by cardiopulmonary exercise test), endurance, physical activity levels, muscle strength, quality of life, fatigue, fear for exercise, disease activity, cardiac function (in children with a Fontan circulation), energy balance, and body composition. Ethics and Dissemination: Conducted according to the Declaration of Helsinki and Good Clinical Practice. Medical-ethical approval was obtained. Trial Registration Number: NL8181, https://www.trialregister.nl/trial/8181.

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.

Impact of Technologic Innovation and COVID-19 Pandemic on Pediatric Cardiology Telehealth

Purpose of Review

Established telehealth practices in pediatrics and pediatric cardiology are evolving rapidly. This review examines several concepts in contemporary telemedicine in our field: recent changes in direct-to-consumer (DTC) pediatric telehealth (TH) and practice based on lessons learned from the pandemic, scientific data from newer technological innovations in pediatric cardiology, and how TH is shaping global pediatric cardiology practice.

Recent Findings

In 2020, the global pandemic of COVID-19 led to significant changes in healthcare delivery. The lockdown and social distancing guidelines accelerated smart adaptations and pivots to ensure continued pediatric care albeit in a virtual manner. Remote cardiac monitoring technology is continuing to advance at a rapid pace secondary to advances in the areas of Internet access, portable hand-held devices, and artificial intelligence.

Summary

TH should be approached programmatically by pediatric cardiac healthcare providers with careful selection of patients, technology platforms, infrastructure setup, documentation, and compliance. Payment parity with in-person visits should be advocated and legislated. Newer remote cardiac monitoring technology should be expanded for objective assessment and optimal outcomes. TH continues to be working beyond geographical boundaries in pediatric cardiology and should continue to expand and develop.

A Path FORWARD: Development of a Comprehensive Multidisciplinary Clinic to Create Health and Wellness for the Child and Adolescent with a Fontan Circulation

Today, it is anticipated most individuals diagnosed with single-ventricle malformation will survive surgical reconstruction through a successful Fontan operation. As greater numbers of patients survive, so has the recognition that individuals with Fontan circulation face a variety of challenges. The goal of a normal quality and duration of life will not be reached by all. The hurdles fall into a variety of domains. From a cardiovascular perspective, the Fontan circulation is fundamentally flawed by its inherent nature of creating a state of chronically elevated venous pressure and congestion, accompanied by a relatively low cardiac output. Ventricular dysfunction, atrioventricular valve regurgitation, and arrhythmia may directly impact cardiac performance and can progress with time. Problems are not limited to the cardiovascular system. Fontan circulatory physiology impacts a multitude of biological processes and health parameters outside the heart. The lymphatic circulation is under strain manifesting as variable degrees of protein-rich lymph loss and immune system dysregulation. Organ system dysfunction develops through altered perfusion profiles. Liver fibrosis is ubiquitous, and a process of systemic fibrogenesis in response to circulatory stressors may affect other organs as well. Somatic growth and development can be delayed. Behavioral and mental health problems are common, presenting as clinically important levels of anxiety and depression. Most striking is the high variability in prevalence and magnitude of these complications within the population, indicating the likelihood of additional factors enhancing or mitigating their emergence. We propose that optimal care for the individual with single ventricle and a Fontan circulation is ideally offered in a comprehensive multidisciplinary manner, with attention to elements that are beyond cardiac management alone. In this report, we share the concepts, our experiences, and perspectives on development of a clinic model-the "Fontan rehabilitation, wellness and resilience development" or FORWARD program. We provide insights into the mechanics of our multidisciplinary model of care and the benefits offered serving our growing population of individuals with a Fontan circulation and their families.

Impairments in Pulmonary Function in Fontan Patients: Their Causes and Consequences

Patients with a Fontan circulation lack a sub-pulmonary ventricle with pulmonary blood flow passively redirected to the lungs. In the Fontan circulation, ventilation has a significant influence on pulmonary blood flow and cardiac output both at rest and with exercise. Children and adults with a Fontan circulation have abnormalities in lung function. In particular, restrictive ventilatory patterns, as measured by spirometry, and impaired gas transfer, as measured by the diffusing capacity of carbon monoxide, have been frequently observed. These abnormalities in lung function are associated with reduced exercise capacity and quality of life. Moderate to severe impairment in lung volumes is independently associated with reduced survival in adults with congenital heart disease. Skeletal and inspiratory muscle weakness has also been reported in patients with a Fontan circulation, with the prospect of improving respiratory muscle function through exercise training programs. In this review, we will present data on cardiopulmonary interactions in the Fontan circulation, the prevalence and severity of impaired lung function, and respiratory muscle function in this population. We will discuss potential causes for and consequence of respiratory impairments, and their impact on exercise capacity and longer-term Fontan outcome. We aim to shed light on possible strategies to reduce morbidity by improving respiratory function in this growing population of 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.

The effects of breathing exercises on respiratory functions, functional capacity and quality of life in vehicle spray painters

Background/aims

Workers engaged in vehicle spray painting are at a risk of developing respiratory problems because of the solvents in the spray paints. Changes in respiratory functions and functional capacities caused by spray painting can be improved with respiratory exercises. The aim of this study was to examine the effects of respiratory exercises on the respiratory functions, functional capacity and quality of life in vehicle spray painters.

Methods

A total of 70 volunteers with similar characteristics participated in the study. The groups were divided into two groups randomly (35 study group, 35 control group). Respiratory functions (value of forced expiratory volume percentage in 1 second [FEV1]), forced vital capacity percentage [FVC], FEV1/FVC percentage, peak expiratory flow percentage [PEF (%)] and maximum voluntary ventilation percentage [MVV (%)]), functional capacity (6-Minute Walk Test) and quality of life (Short Form Health Survey [SF-36]) were evaluated. The study group undertook supervised breathing exercises 3 days a week for 6 weeks. The same exercises were given to the control group as a home programme. Home programmes were followed up by telephone calls. Evaluations were performed again after 6 weeks.

Results

In the study group, FEV1 (%) increased more than in the control group (P<0.05). The increase in PEF (%) was similar in both groups (P>0.05). In the study group, FEV1/FVC (%) and MVV (%) were significantly different before and after the intervention (P<0.05), but there was no difference in the control group (P>0.05). There was a greater increase in the study group than in the control group (P<0.05). 6-Minute Walk Test distance (m) before and after the intervention in both groups were similar (P>0.05). Before and after the intervention, a significant difference was found in the vitality and the social function domains of the SF-36 in the study group. In the comparisons of groups, a significant difference was found in the study group in the role-emotional, social function and bodily pain domains of the SF-36 after the intervention (P<0.05).

Conclusions

Breathing exercises can be recommended for vehicle spray painters to avoid an increase in respiratory resistance and to improve their quality of life.

Deficits in the Functional Muscle-Bone Unit in Youths with Fontan Physiology

OBJECTIVE

To determine whether dual energy X-ray absorptiometry (DXA), a clinically available tool, mirrors the magnitude of deficits in trabecular and cortical bone mineral density (BMD) demonstrated on peripheral quantitative computed tomography in youth with Fontan physiology.

STUDY DESIGN

We aimed to describe DXA-derived BMD at multiple sites and to investigate the relationship between BMD and leg lean mass, a surrogate for skeletal muscle loading. Subjects with Fontan (n = 46; aged 5-20 years) underwent DXA in a cross-sectional study of growth and bone and muscle health as described previously. Data from the Bone Mineral Density in Childhood Study were used to calculate age-, sex-, and race-specific BMD z-scores of the whole body, lumbar spine, hip, femoral neck, distal one-third radius, ultradistal radius, and leg lean mass z-score (LLMZ).

RESULTS

Fontan BMD z-scores were significantly lower than reference at all sites-whole body, -0.34 ± 0.85 (P = .01); spine, -0.41 ± 0.96 (P = .008); hip, -0.75 ± 1.1 (P < .001); femoral neck, -0.73 ± 1.0 (P < .001); distal one-third radius, -0.87 ± 1.1 (P < .001); and ultradistal radius. -0.92 ± 1.03 (P < .001)-as was LLMZ (-0.93 ± 1.1; P < .001). Lower LLMZ was associated with lower BMD of the whole body (R² = 0.40; P < .001), lumbar spine (R² = 0.16; P = .005), total hip (R² = 0.32; P < .001), femoral neck (R² = 0.47; P < .001), and ultradistal radius (R² = 0.35; P < .001).

CONCLUSIONS

Patients with Fontan have marked deficits in both cortical (hip, distal one-third radius) and trabecular (lumbar spine, femoral neck, ultradistal radius) BMD. Lower LLMZ is associated with lower BMD and may reflect inadequate skeletal muscle loading. Interventions to increase muscle mass may improve bone accrual.

The Influence of Respiration on Blood Flow in the Fontan Circulation: Insights for Imaging-Based Clinical Evaluation of the Total Cavopulmonary Connection

Congenital heart disease is the most common birth defect and functionally univentricular heart defects represent the most severe end of this spectrum. The Fontan circulation provides an unique solution for single ventricle patients, by connecting both caval veins directly to the pulmonary arteries. As a result, the pulmonary circulation in Fontan palliated patients is characterized by a passive, low-energy circulation that depends on increased systemic venous pressure to drive blood toward the lungs. The absence of a subpulmonary ventricle led to the widely believed concept that respiration, by sucking blood to the pulmonary circulation during inspiration, is of great importance as a driving force for antegrade blood flow in Fontan patients. However, recent studies show that respiration influences pulsatility, but has a limited effect on net forward flow in the Fontan circulation. Importantly, since MRI examination is recommended every 2 years in Fontan patients, clinicians should be aware that most conventional MRI flow sequences do not capture the pulsatility of the blood flow as a result of the respiration. In this review, the unique flow dynamics influenced by the cardiac and respiratory cycle at multiple locations within the Fontan circulation is discussed. The impact of (not) incorporating respiration in different MRI flow sequences on the interpretation of clinical flow parameters will be covered. Finally, the influence of incorporating respiration in advanced computational fluid dynamic modeling will be outlined.

Dynamic exercise changes in venous pressure and liver stiffness in Fontan patients: effects of Treprostinil

BACKGROUND

Systemic venous hypertension and low cardiac output are believed to be important mediators of liver injury after the Fontan procedure. Pulmonary vasodilators have the potential to improve such haemodynamics. The aim of this study was to assess the acute effects of exercise on liver stiffness and venous pressures and to assess the impact of inhaled Treprostinil on this response.

METHODS

In this prospective, double-blind, placebo-controlled, crossover trial, 14 patients with a Fontan circulation were randomised to inhalation of placebo and Treprostinil. Incremental and constant work rate exercise tests were performed to assess the effect of Treprostinil on exercise tolerance. Venous pressures were measured throughout and liver stiffness at rest and immediately after peak exercise.

RESULTS

Mean age was 27.8 ± 7.9 years and 66% were females. Exercise acutely increased liver stiffness by 30% (mean shear wave speed: 2.38 ± 0.71 versus 2.89 ± 0.51 ms, p = 0.02). Peripheral venous pressures increased acutely during both incremental (12.1 ± 2.4 versus 22.6 ± 8.0 mmHg, p < 0.001) and constant work rate exercise (12.5 ± 2.5 versus 23.4 ± 5.2 mmHg, p < 0.001). Overall, Treprostinil failed to attenuate exercise-induced increases in liver stiffness. Compared with placebo, Treprostinil did not significantly impact venous pressure responses, VO2peak, nor exercise endurance times.

CONCLUSIONS

Peripheral venous pressure increased acutely during exercise by an average of 88% above baseline and was not altered by administration of inhaled Treprostinil. Liver stiffness measured immediately post-exercise increased acutely by an average of 30%, with no attenuation following Treprostinil inhalation.

Cardiac Rehabilitation in German Speaking Countries of Europe-Evidence-Based Guidelines from Germany, Austria and Switzerland LLKardReha-DACH-Part 2

Background: Scientific guidelines have been developed to update and harmonize exercise based cardiac rehabilitation (ebCR) in German speaking countries. Key recommendations for ebCR indications have recently been published in part 1 of this journal. The present part 2 updates the evidence with respect to contents and delivery of ebCR in clinical practice, focusing on exercise training (ET), psychological interventions (PI), patient education (PE). In addition, special patients’ groups and new developments, such as telemedical (Tele) or home-based ebCR, are discussed as well. Methods: Generation of evidence and search of literature have been described in part 1. Results: Well documented evidence confirms the prognostic significance of ET in patients with coronary artery disease. Positive clinical effects of ET are described in patients with congestive heart failure, heart valve surgery or intervention, adults with congenital heart disease, and peripheral arterial disease. Specific recommendations for risk stratification and adequate exercise prescription for continuous-, interval-, and strength training are given in detail. PI when added to ebCR did not show significant positive effects in general. There was a positive trend towards reduction in depressive symptoms for “distress management” and “lifestyle changes”. PE is able to increase patients’ knowledge and motivation, as well as behavior changes, regarding physical activity, dietary habits, and smoking cessation. The evidence for distinct ebCR programs in special patients’ groups is less clear. Studies on Tele-CR predominantly included low-risk patients. Hence, it is questionable, whether clinical results derived from studies in conventional ebCR may be transferred to Tele-CR. Conclusions: ET is the cornerstone of ebCR. Additional PI should be included, adjusted to the needs of the individual patient. PE is able to promote patients self-management, empowerment, and motivation. Diversity-sensitive structures should be established to interact with the needs of special patient groups and gender issues. Tele-CR should be further investigated as a valuable tool to implement ebCR more widely and effectively.

Cardiac Rehabilitation in German Speaking Countries of Europe-Evidence-Based Guidelines from Germany, Austria and Switzerland LLKardReha-DACH-Part 1

BACKGROUND

Although cardiovascular rehabilitation (CR) is well accepted in general, CR-attendance and delivery still considerably vary between the European countries. Moreover, clinical and prognostic effects of CR are not well established for a variety of cardiovascular diseases.

METHODS

The guidelines address all aspects of CR including indications, contents and delivery. By processing the guidelines, every step was externally supervised and moderated by independent members of the "Association of the Scientific Medical Societies in Germany" (AWMF). Four meta-analyses were performed to evaluate the prognostic effect of CR after acute coronary syndrome (ACS), after coronary bypass grafting (CABG), in patients with severe chronic systolic heart failure (HFrEF), and to define the effect of psychological interventions during CR. All other indications for CR-delivery were based on a predefined semi-structured literature search and recommendations were established by a formal consenting process including all medical societies involved in guideline generation.

RESULTS

Multidisciplinary CR is associated with a significant reduction in all-cause mortality in patients after ACS and after CABG, whereas HFrEF-patients (left ventricular ejection fraction <40%) especially benefit in terms of exercise capacity and health-related quality of life. Patients with other cardiovascular diseases also benefit from CR-participation, but the scientific evidence is less clear. There is increasing evidence that the beneficial effect of CR strongly depends on "treatment intensity" including medical supervision, treatment of cardiovascular risk factors, information and education, and a minimum of individually adapted exercise volume. Additional psychologic interventions should be performed on the basis of individual needs.

CONCLUSIONS

These guidelines reinforce the substantial benefit of CR in specific clinical indications, but also describe remaining deficits in CR-delivery in clinical practice as well as in CR-science with respect to methodology and presentation.