The role of exercise testing in pediatric cardiology

Clinical Application of Exercise Stress Echocardiography in an Outpatient Pediatric Population

Background: Exercise stress echocardiography (ESE) is commonly employed in adults, but its applicability in pediatric populations remains to be clarified. Methods: A total of 309 consecutive children (C), with a mean age of 14.1 ± 2.6 years (range 6-17 years), underwent treadmill ESE starting in 2002. They were divided into two groups: Group I comprised 258 children, including 237 with symptoms related to exercise (such as chest pain, fatigue, lipothymia/syncope, or one aborted sudden death), 15 with electrocardiogram (ECG) abnormalities, and 6 with a positive ECG stress test showing ST changes. Group II consisted of 10 asymptomatic children whose parents requested routine screening, 11 with symptoms unrelated to exercise, 12 with a family history of sudden death, and 17 with known pathologies (including 10 with hypertrophic cardiomyopathy, 2 with aortic coarctation, and the remainder with various conditions, such as Cortriatriatum sinister, pulmonary stenosis, subaortic stenosis, bicuspid aortic valve, left ventricular hypertrophy related to arterial hypertension, and aortic switch operation). Regional wall motion abnormalities (RWMAs) and transvalvular or intraventricular (IVG) gradients were assessed using 2D and continuous-wave Doppler, respectively, in all cases. Results: The success rate was 100% (309/309). Stress-induced RWMAs were observed in two children. A significant IVG (>30 mmHg) was detected in 101 out of the 258 children (39%) in Group I, who presented with exercise-related symptoms, ECG abnormalities, or positive stress ECG. In Group I, the odds ratio (OR) of ESE reproducing the symptoms in children with IVG compared to those without IVG was 8.22 (95% CI: 4.84-13.99, p < 0.001). Conclusions: Treadmill ESE is both feasible and safe for pediatric populations. RWMAs demonstrated limited utility in our cohort of children, while IVG induced by exercise was frequently observed in symptomatic children.

Exercise-Induced Electrocardiography Changes in Pulmonary Arterial Hypertension

Cardiopulmonary exercise testing (CPET) is an important tool in assessing the functional status of patients with pulmonary arterial hypertension (PAH). During CPET, continuous electrocardiography (ECG) is used as a marker of exercise-induced ischemia or arrhythmia. We hypothesize that ECG changes with exercise may be an early indicator of clinical worsening in PAH and could predict adverse outcomes. Clinical, hemodynamic, and CPET data of 155 children and young adult patients with PAH who underwent CPET between 2012 and 2019 in our pulmonary hypertension (PH) center were included in this retrospective analysis. ECGs were analyzed for ST depressions and T-wave inversions, along with coincident hemodynamic data. These data were correlated with adverse outcomes divided into 2 categories: severe worsening (death or receiving lung transplant) and mild to moderate worsening (PAH medication escalation, hospitalization, shunt creation, or listing for lung transplant). The median age was 19 years (range 7 to 40 years), 69% were female, and the average follow-up time was 5 years (range 1 to 8 years). A total of 63 patients (41%) had at least 1 adverse outcome. A total of 39 patients (25%) demonstrated significant ST-T-wave changes with exercise. Patients with ST-T-wave changes were 20% more likely to die or need lung transplant than those without. The multiple linear regression found that ST-T-wave changes were a predictor of elevated mean pulmonary arterial pressure (mPAP) found on catheterization (R = 0.489, p = 0.003), although not of pulmonary vascular resistance index (R = -0.112, p = 0.484). An mPAP of 55 mm Hg was the most sensitive and specific point in identifying when ST-T-wave changes with exercise begin to appear. In conclusion, ST-T-wave changes on exercise ECG are significantly associated with adverse outcomes in PH in a medium-term follow-up study, and the presence of ST-T-wave changes correlates with higher mPAP. These ECG changes with exercise may be used as early indicators of clinical worsening in PH and predictors of adverse outcomes.

Physical exercise and cardiovascular response: design and implementation of a pediatric CMR cohort study

To examine feasibility and reproducibility and to evaluate the cardiovascular response to an isometric handgrip exercise in low-risk pediatric population using Cardiovascular Magnetic Resonance measurements. In a subgroup of 207 children with a mean age of 16 years participating in a population-based prospective cohort study, children performed an isometric handgrip exercise. During rest and exercise, continuous heart rate and blood pressure were measured. Cardiovascular magnetic resonance (CMR) measurements included left ventricular mass, aortic distensibility and pulse wave velocity at rest and left ventricular end-diastolic and end-systolic volumes, ejection fraction, stroke volume and cardiac output during rest and exercise. 207 children had successful CMR measurements in rest and 184 during exercise. We observed good reproducibility for all cardiac measurements. Heart rate increased with a mean ± standard deviation of 42.6% ± 20.0 and blood pressure with 6.4% ± 7.0, 5.4% ± 6.1 and 11.0% ± 8.3 for systolic, diastolic and mean arterial blood pressure respectively (p-values < 0.05). During exercise, left ventricular end-diastolic and end-systolic volumes and cardiac output increased, whereas left ventricular ejection fraction slightly decreased (p-values < 0.05). Stroke volume did not change significantly. A sustained handgrip exercise of 7 min at 30-40% maximal voluntary contraction is a feasible exercise-test during CMR in a healthy pediatric population, which leads to significant changes in heart rate, blood pressure and functional measurements of the left ventricle in response to exercise. This approach offers great novel opportunities to detect subtle differences in cardiovascular health.

Complications of exercise and pharmacologic stress echocardiography

Stress echocardiography is a diagnostic cardiovascular exam that is commonly utilized for multiple indications, including but not limited to the assessment of obstructive coronary artery disease, valvular disease, obstructive hypertrophic cardiomyopathy, and diastolic function. Stress echocardiography can be performed via both exercise and pharmacologic modalities. Exercise stress is performed with either treadmill or bicycle-based exercise. Pharmacologic stress is performed via either dobutamine or vasodilator-mediated (i.e., dipyridamole, adenosine) stress testing. Each of these modalities is associated with a low overall prevalence of major, life-threatening adverse outcomes, though adverse events are most common with dobutamine stress echocardiography. In light of the recent COVID-19 pandemic, the risk of infectious complications to both the patient and stress personnel cannot be negated; however, when certain precautions are taken, the risk of infectious complications appears minimal. In this article, we review each of the stress echocardiographic modalities, examine major potential adverse outcomes and contraindications, assess the risks of stress testing in the setting of a global pandemic, and examine the utilization and safety of stress testing in special patient populations (i.e., language barriers, pediatric patients, pregnancy).

Cardiopulmonary Fitness of Preschoolers with Congenital Heart Disease: An Observational Study

With advancements in cardiopulmonary rehabilitation over the past few decades, the survival rate of patients with congenital heart disease (CHD) has increased. However, the Cardiopulmonary fitness (CPF) of these patients is poor. Here, we aimed to investigate CPF in preschoolers with CHD (aged 4 to 6 years) using cardiopulmonary exercise testing. We retrospectively compared 102 healthy preschoolers with 80 preschoolers with CHD. The latter had lower peak oxygen consumption, oxygen consumption at anaerobic threshold and metabolic equivalent at anaerobic threshold. The same result was observed in boys with CHD, but not in girls, when sex was sub-analyzed. Considering the body composition, children with CHD had a lower fat-free mass index (FFMI) than their healthy peers. Healthy preschoolers with a normal body mass index (BMI) had higher anaerobic threshold and peak metabolic equivalent values than overweight or underweight children. This was categorized under the BMI reference of the Ministry of Health and Welfare in Taiwan. In conclusion, the CPF difference between the CHD and healthy groups was identified as early as in preschool age, and better CPF in healthy preschoolers within the normal BMI range suggests the importance of weight control in young children.

Normative values and a new predicted model of exercise blood pressure in young athletes

OBJECTIVES

Assessing the systolic and diastolic blood pressure during acute physical exertion can allow the discovery of many cardiovascular diseases even at a young age. However, this response depends on the age, sex of the subject, and the modality of the graded exercise test. This study aims to provide sex-and age-related normative values of peak and recovery blood pressure performance and to develop a predicted model of systolic and diastolic blood pressure peak in young athletes.

DESIGN

Retrospective-study.

METHODS

We analyzed 8224 young athletes (5516 males and 2708 females) aged between 8 and 18. Anthropometric and blood pressure parameters related to the effort are reported. Then, according to sex, graded exercise test modality, and age were calculated 1) the fifth, tenth, fiftieth, ninetieth, and ninety-fifth percentiles for the systolic and diastolic blood pressure at peak and after 1 min of recovery and 2) predictive equations of systolic and diastolic blood pressure at the peak.

RESULTS

Younger athletes show lower peak blood pressure values, gradually increasing as they age. Males showed higher peak systolic blood pressure values starting at 12-13 years on the cycle ergometer and 10-11 years on the treadmill, while there was no difference in peak diastolic blood pressure values.

CONCLUSIONS

Sex, age, and the specificity of the movement performed must be considered in assessing the blood pressure response in the young population. In addition, providing reference values and predictive equations of blood pressure response to acute physical exertion may allow for a better functional assessment of young athletes.

Exercise electrocardiogram for risk-based screening of severe residual coronary lesion in children after coronary surgery

BACKGROUND

Residual severe coronary artery (CA) lesion (SCL) in children after cardiac surgery involving the CA is a major concern.

AIM

To evaluate the value of exercise electrocardiogram (eECG) for risk-based screening of SCL.

METHODS

We analysed 135 maximal eECG from 115 children (mean age 13.6±3.7 years) who underwent concomitant CA imaging. SCL was defined as a stenosis exceeding 50%.

RESULTS

Underlying congenital heart diseases were transposition of the great arteries (TGA) (n = 116), CA pathway anomaly (n = 13) and left CA from the pulmonary artery (n = 6). Eleven SCLs were identified in 10 patients, of which 3 had a known untreated non-severe lesion and 4 had no lesions on previous imaging. In multivariable analysis, risks markers for SCL were effort chest pain (OR: 4.72, 95% CI: 1.23-18.17; P=0.024), intramural pathway (OR: 4.37, 95% CI: 1.14-16.81; P=0.032). Yacoubs C-type CA was added as a risk marker for patients with TGA (P=0.0009). All patients with SCL had a positive eECG (sensitivity: 100%, 95% CI: 72-100). Specificity was 81% (95% CI: 73-87). In the low-risk group (0 risk markers), 3/95 patients had SCL (3%), and the post-test probability of SCL with positive eECG (PPr+) was 15% (95% CI: 8-21). In the high-risk group (≥1 risk marker) comprising 8/40 SCLs (20%), PPr+ was 53% (95% CI: 35-67).

CONCLUSIONS

Most SCL tended to develop gradually, years after surgery. Provided it is near maximal, a negative eECG appears sufficient to exclude SCL. In the high-risk group, PPr+ exceeded 50%.

Cardiac Evaluation of Exercise Testing in a Contemporary Population of Preschool Children: A New Approach Providing Reference Values

The objective of this study was to evaluate cardiac autonomic function at rest, during maximal exercise, and in post-exercise recovery, to determine sex-specific and age-specific differences in resting heart rate (RHR), linear and spectral parameters of Heart Rate Variability (HRV), HR_peak, and heart rate recovery (HRR) after one and five minutes, in preschool children. This study involved a cohort of 167 healthy children (79 girls) aged 3 to 6 years that were selected from several schools in southern Spain. A 10 × 20 m test was conducted, and the cardiovascular response was recorded. No significant differences were found in all variables between the sexes. However, a significant reduction in RHR and an increase in HRR were found from age 4 to age 6. HRV parameters at rest were higher in older children. No associations between 10 × 20 m performance, weight status, and cardiac parameters were found. Simple linear regression analysis revealed that heart rate reserve (HRr), HRR_5min, RMSSD, and HF were the variables that showed association with all HR parameters. There was also a significant correlation between HRr and HRR_5min. In conclusion, cardiovascular autonomic function during rest, exercise, and recovery in Spanish preschool children was not influenced by sex, although older children showed greater cardiovascular modulation. Cardiorespiratory fitness status was not associated with HR response.

ARTP statement on cardiopulmonary exercise testing 2021

Cardiopulmonary exercise testing (CPET) has become an invaluable tool in healthcare, improving the diagnosis of disease and the quality, efficacy, assessment and safety of treatment across a range of pathologies. CPET's superior ability to measure the global exercise response of the respiratory, cardiovascular and skeletal muscle systems simultaneously in a time and cost-efficient manner has led to the application of CPET in a range of settings from diagnosis of disease to preoperative assessment. The Association for Respiratory Technology and Physiology Statement on Cardiopulmonary Exercise Testing 2021 provides the practitioner and scientist with an outstanding resource to support and enhance practice, from equipment to testing to leadership, helping them deliver a quality assured service for the benefit of all patient groups.

Cardiopulmonary function findings of pediatric patients with patent ductus arteriosus

Transcatheter occlusion and surgical ligation are the treatments of choice for most patent ductus arteriosus (PDA) in children. Fifty-five children who had PDA completed a pulmonary function test and a symptom-limited treadmill exercise test from 2016 to 2018 at 1 medical center in southern Taiwan. The study group was divided into surgical ligation and catheterization groups, which were compared to a healthy control group matched for age, sex, and body mass index. Data about the performance on the exercise test, including metabolic equivalent at anaerobic threshold and peak, were analyzed. No differences in the pulmonary function and ventilatory parameters were observed between the surgery, catheterization, and control groups. Heart rate at peak and at anaerobic threshold significantly differed in the investigated groups. The post hoc analysis showed that the surgery group had a lower heart rate at peak and threshold compared to the catheterization and control groups (P = .02, P < .001, respectively). No significant difference was found between the catheterization group and the control group. A larger and younger group of patients were recruited, allowing for newer data about the cardiopulmonary function to be obtained. The findings suggest that patients with PDA could undergo physical training after intervention. The imposition of restrictions to limit sports activities should be avoided.

Safety and feasibility of symptom-limited cardiopulmonary exercise test using the modified Naughton protocol in children with cerebral palsy: An observational study

ABSTRACT

Variables derived from the cardiopulmonary exercise test (CPX) provide objective information regarding the exercise capacity of children with cerebral palsy (CP), which can be used as the basis for exercise recommendations. Performing maximal CPX might not be appropriate, safe, or practical for children with CP. In the present study, the safety and feasibility of symptom-limited CPX using the modified Naughton protocol, a submaximal protocol, were investigated in children with CP, Gross Motor Function Classification System (GMFCS) level I or II. The present study included 40 children aged 6 to 12 years with CP who underwent symptom-limited CPX. CPX was performed to measure cardiopulmonary fitness using a treadmill with a modified Naughton protocol. Motor capacity was assessed using the Gross Motor Function Measure (GMFM), Pediatric Balance Scale (PBS), Timed Up and Go (TUG) test, and 6-minute walk test. Thirty-seven children with CP successfully completed testing without any adverse events during or immediately after CPX (dropout rate 7.5%). The reason for test termination was dyspnea (51.4%) or leg fatigue (48.6%). Based on the respiratory exchange ratio (RER), 21 of 37 (56.8%) children chose premature termination. The relationship between the reason for test termination and RER was not statistically significant (Spearman rho = 0.082, P = .631). CPX exercise time was strongly correlated with GMFM (Spearman rho = 0.714) and moderate correlation with PBS (Spearman rho = 0.690) and TUG (Spearman rho = 0.537). Peak oxygen uptake during CPX showed a weak correlation with GMFM and a moderate correlation with PBS. This study revealed that symptom-limited CPX using the modified Naughton protocol was safe and feasible for children with CP and GMFCS level I or II.

Improved Carotid Elasticity but Altered Central Hemodynamics and Carotid Structure in Young Athletes

Young athletes most often exceed the physical activity recommendations of the World Health Organization. Therefore, they are of special interest for investigating cardiovascular adaptions to exercise. This study aimed to examine the arterial structure and function of young athletes 12-17 years old and compare these parameters to reference values of healthy cohorts. Carotid intima-media thickness (cIMT), carotid diameter, cIMT÷carotid diameter-ratio (cIDR), arterial compliance (AC), elastic modulus (Ep), β stiffness index (β), and carotid pulse wave velocity (PWVβ) were determined using ultrasound in 331 young athletes (77 girls; mean age, 14.6 ± 1.30 years). Central systolic blood pressure (cSBP) and aortic PWV (aPWV) were measured using the oscillometric device Mobil-O-Graph. Standard deviation scores (SDS) of all parameters were calculated according to German reference values. The 75th and 90th percentiles were defined as the threshold for elevated cIMT and arterial stiffness, respectively. Activity behavior was assessed with the MoMo physical activity questionnaire, and maximum power output with a standard cardiopulmonary exercise test. One-sample t-tests were performed to investigate the significant deviations in SDS values compared to the value "0". All subjects participated in competitive sports for at least 6 h per week (565.6 ± 206.0 min/week). Of the 331 young athletes, 135 (40.2%) had cIMT >75th percentile, 71 (21.5%) had cSBP >90th percentile, and 94 (28.4%) had aPWV>90th percentile. We observed higher cIMT SDS (p < 0.001), cIDR SDS (p = 0.009), and AC SDS (p < 0.001) but lower β SDS (p < 0.001), Ep SDS (p < 0.001), and PWVβ SDS (p < 0.001) compared to the reference cohort. The cSBP SDS (p < 0.001) and aPWV SDS (p < 0.001) were elevated. In conclusion, cIMT and cIDR were higher in young athletes than in a reference cohort. Furthermore, young athletes presented better carotid elasticity and lower arterial stiffness of the carotid artery. However, central arterial stiffness was higher compared to the reference cohort. The thickening of the carotid intima-media complex in combination with a reduction in arterial stiffness indicates a physiological adaptation to exercise in youth.

Exercise-induced electrocardiographic changes after treadmill exercise testing in healthy children: A comprehensive study

Background:

Aims and Objectives:

Materials and Methods:

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Conclusion:

The Cardiovascular Stress Response as Early Life Marker of Cardiovascular Health: Applications in Population-Based Pediatric Studies-A Narrative Review

Stress inducement by physical exercise requires major cardiovascular adaptations in both adults and children to maintain an adequate perfusion of the body. As physical exercise causes a stress situation for the cardiovascular system, cardiovascular exercise stress tests are widely used in clinical practice to reveal subtle cardiovascular pathology in adult and childhood populations with cardiac and cardiovascular diseases. Recently, evidence from small studies suggests that the cardiovascular stress response can also be used within research settings to provide novel insights on subtle differences in cardiovascular health in non-diseased adults and children, as even among healthy populations an abnormal response to physical exercise is associated with an increased risk of cardiovascular diseases. This narrative review is specifically focused on the possibilities of using the cardiovascular stress response to exercise combined with advanced imaging techniques in pediatric population-based studies focused on the early origins of cardiovascular diseases. We discuss the physiology of the cardiovascular stress response to exercise, the type of physical exercise used to induce the cardiovascular stress response in combination with advanced imaging techniques, the obtained measurements with advanced imaging techniques during the cardiovascular exercise stress test and their associations with cardiovascular health outcomes. Finally, we discuss the potential for cardiovascular exercise stress tests to use in pediatric population-based studies focused on the early origins of cardiovascular diseases.

Does Ramadan Observance Affect Cardiorespiratory Capacity of Healthy Boys?

Studies raising the issue of the effects of Ramadan observance (RO) on boys' 6-min walk test (6MWT) data are rare. The studies, which did not include control groups of non-fasters, presented contradictory results. This study aimed to compare the 6MWT data (6-min walk distance [6MWD; m, %predicted], heart rate [HR; bpm, % of maximal predicted HR]), oxy-hemoglobin saturation (Oxy-sat; %), systolic and diastolic blood pressures (SBP and DBP, respectively; mmHg) determined at rest (_Rest and at the end _End of the test) of a group of 22 healthy fasting boys (age: 12 to 15 years) with an age-matched non-fasting group (n = 10). The 6MWTs were performed during three experimental conditions (ECs): Pre-Ramadan, Mid-Ramadan, and Post-Ramadan. The two groups' 6MWT data for each EC were compared, and repeated factorial analysis of variance (2 groups vs. 3 ECs) was performed. Both groups had similar values of 6MWD (m, %predicted), HR_Rest or HR_End (bpm, % of maximal predicted HR), Oxy-sat_Rest, Oxy-sat_End, SBP_Rest, and DBP_Rest during the three ECs. Compared to the non-fasting group, the fasting group had significantly higher SBP_End (121 ± 10 vs. 130 ± 11) and DBP_End (72 ± 6 vs. 78 ± 7) determined during the Mid-Ramadan EC. No significant interactive effects of the groups (2) vs. ECs (3) was found for the 6MWD (%predicted; p = .809), HR_Rest (%, p = .555), HR_End (%, p = .964), Oxy-sat_Rest (p = .336), Oxy-sat_End (p = .389), SBP_Rest (p = .708), SBP_End (p = .548), DBP_Rest (p = .277), and DBP_End (p = .096). To conclude, in boys, RO does not impact the 6MWD, HR, or Oxy-sat, but it has minimal impact on the SBP_End and DBP_End.

Exercise Field Testing in Children: A New Approach for Age-Appropriate Evaluation of Cardiopulmonary Function

Based on the wide range of problems to effectively perform cardiopulmonary testing in young children, this study strives to develop a new cardiopulmonary exercise test for children using a mobile testing device worn in a backpack in order to test children during their natural movement habits, namely, running outdoors. A standard cardiopulmonary exercise ramp test on a cycle ergometer was performed by a group of twenty 7-10-year-old children. The results were compared with a self-paced incremental running test performed using a mobile cardiopulmonary exercise measuring device in an outdoor park. The children were able to reach significantly higher values for most of the cardiopulmonary exercise variables during the outdoor test and higher. Whereas a plateau in [Formula: see text] was reached by 25% of the children during the outdoor test, only 75% were able to reach a reasonable VT2, let alone [Formula: see text], during the bicycle test. The heart rate at VT1, the O₂-pulse, and the OUES were comparable between both tests. OUES was also positively correlated with [Formula: see text] in both tests. Testing children outdoors using a mobile cardiopulmonary exercise unit represents an alternative to standard exercise testing, but without the added problems of exercise equipment like treadmills or bicycles. It allows for individualized exercise testing with the aim of standardized testing durations instead of standardized testing protocols. The running speeds determined during the outdoor tests may then be used to develop age-adapted testing protocols for treadmill testing.

[Exercise testing: New guidelines]

The GERS-P (Exercise Rehabilitation Sports Prevention Group of the French Society of Cardiology) has decided to update current guidelines regarding the practice of EKG stress tests. Since the last update dates from 1997, the GERS judged it necessary to integrate data from new works and advancements made in the last 20 years. Good clinical practices and safety conditions are better defined regarding the structure, location, material, staff competency, as well as convention with hospital structures. The diagnosis of coronary artery disease remains the principal indication for a stress test. Interpretation of the results is crucial - it must be multivariate and provide either a low, intermediate or strong probability of the existence of coronary lesions, taking into account the studied population (risk factors, age, sex and symptoms). We no longer have to talk about a "positive, negative or litigious" test. Several new indications for a stress test have been defined for the assessment of cardiac pathologies. With such indications, the use of gas expiration measurements is highly recommended in order to provide a precise prognosis for all the various cardiac pathologies : congenital, ischemic, valvular, cardiomyopathy, congestive heart failure, rhythm and conduction disorders, pacemaker fine-tuning, or pulmonary hypertension. Indications for stress tests and contraindications are defined according to different population subgroups, for instance : athletes, women, children, the elderly, asymptomatic patients, diabetics, hypertensive patients, peripheral arteritis disease patients, or in the context of a non-cardiac surgery pre-op visit. The new guidelines are considerably different from those dating from 1997 and further pinpoint the relevance and importance of an EKG stress test within the arsenal of complementary cardiologic exams. With the improvements made in providing diagnostic value in CAD, as well as better prognostic value for any underlying pathology, the indication for an EKG stress test has extended to all cardiovascular disease.

Comparison of cardiorespiratory fitness between preschool children with normal and excess body adipose ~ An observational study

Objective

Overweight and obesity in preschoolers might develop into childhood and even adulthood obesity. Overweight and obesity have been shown to be negatively related with cardiorespiratory fitness (CRF) in children and adults but few studies did among preschoolers. We aimed to evaluate whether excess body adipose is negatively associated with CRF in both the submaximal and maximal effort of preschool children in exercise testing and to examine if there is difference to achieve maximal effort during exercise testing between preschoolers with normal and excess body adipose.

Methods

Data of 106 preschoolers aged 4–6 that received symptom-limited treadmill exercise testing was analyzed. Anthropometry was measured by vector bioelectrical impedance analysis. Excess body adipose was defined as (1) ‘overweight’ and ‘obesity’ by body mass index (BMI), (2) fat mass index (FMI) greater than the sex- and age-specific 75th percentile of whole subjects, and (3) fat-free mass index (FFMI) smaller than the sex- and age-specific 25th percentile. CRF was indicated by metabolic equivalent (MET) at anaerobic threshold (AT MET), peak MET, oxygen uptake efficiency slope (OUES) calculated by the 50% (OUES-50) and the entire (OUES-100) duration of the exercise testing.

Results

Preschoolers with excess body adipose by three different definitions (BMI, FMI, and FFMI) all had poorer ability to perform maximal effort (p = 0.004, 0.043, and 0.007, respectively). Preschoolers with excess body adipose by BMI and FFMI classifications had lower OUES-50 (p = 0.018, and 0.001, respectively), and lower OUES-100 (p = 0.004, and 0.001, respectively) than peers with normal body adipose during exercise testing while those with excess body adipose by FMI classification showed no significant differences from peers with normal body adipose in both OUES-50 and OUES-100.

Conclusions

Preschoolers with excess body adipose had lower CRF significantly during treadmill exercise testing. Weight control and health promotion should start as early as possible.

Prediction of peak V˙ O2 in Children and Adolescents With HIV From an Incremental Cycle Ergometer Test

PURPOSE

To examine the capacity of physiological variables and performance to predict peak oxygen consumption (peak V˙ O₂) in children and adolescents living with HIV.

METHOD

Sixty-five children and adolescents living with HIV (30 boys) aged 8-15 years, participated in the study. Peak V˙ O₂ was measured by breath-by-breath respiratory exchange during an incremental cycle ergometer until volitional exhaustion. Information on the time to exhaustion, maximal power output (Pmax), and peak heart rate (peak HR) were also recorded.

RESULTS

Predictive models were developed and all equations showed the ability of performance variables to predict peak V˙ O₂. However, Model 1 was based only on Pmax by following equation: Y = 338.8302 + (Pmax [W] * 11.16435), R² = 0.90 and standard error of estimation (SEE) = 180 ml ⋅ min^-1.

CONCLUSION

The V˙ O₂ peak can be predicted simply by the Pmax obtained from the incremental cycle ergometer test. This protocol is a valid and useful tool for monitoring the aerobic fitness of children and adolescents living with HIV, especially in resource-limited settings.

Ability of preschoolers to achieve maximal exercise and its correlation with oxygen uptake efficiency slope ∼ an observational study by direct cardiopulmonary exercise testing

The oxygen uptake efficiency slope (OUES) is a well-established substitute for maximum oxygen uptake ((Equation is included in full-text article.)O2 max) in submaximal exercise effort among adolescents and adults. Few studies have analyzed the exercise capacity (EC) and OUES of children aged 4 to 6 (preschoolers). Body fat has been proved to negatively affect EC among schoolchildren. The purposes of this study were to assess the capacity of preschoolers in achieving (Equation is included in full-text article.)O2 max and evaluate the correlation of peak metabolic equivalent (peak MET) and peak oxygen consumption (peak O2) with OUES. We also evaluated if body fat affected EC among preschoolers.Forty-three preschoolers under the ramped Bruce protocol of treadmill exercise testing had been retrospectively studied. The criteria for achieving (Equation is included in full-text article.)O2 max included respiratory exchange ratio (RER) >1.1, heart rate (HR) >85% of age-predicted maximum, and HR >200 bpm. OUES was calculated by the 75% (OUES-75) and the entire (OUES-100) duration of the testing and normalized by body surface area. Body fat was measured using vector bioelectrical impedance analysis. The fat mass (FM) index and fat-free mass index (FFMI) were defined as FM or FFM (kg) divided by height squared (m), respectively.The mean age of the participants was 5.70 ± 0.56. Seventy-nine percent of preschoolers met at least 1 criterion, 36.84% met 2 criteria, and none met all 3 criteria for (Equation is included in full-text article.)O2. OUES-75 was moderately positively correlated with peak MET (P = .034; Spearman's rho = 0.324) and peak O2 (P <.001; Spearman's rho = 0.667). OUES-100 was moderately to highly positively correlated with peak MET (P <.001; Spearman's rho = 0.592) and peak O2 (P <.001; Spearman's rho = 0.825). There were moderate to high positive correlations between FFMI and peak O2 (P <.001; Spearman's rho = 0.668), OUES-75 (P <.001; Spearman's rho = 0.642), and OUES-100 (P < .001; Spearman's rho = 0.670).None of the preschoolers reached all 3 criteria for (Equation is included in full-text article.)O2max. OUES-75 and OUES-100 might be indicators of peak O2 at submaximal effort. Preschoolers with higher FFMI had better EC during treadmill exercise testing.

Incidence and Predictors of Clinically Important and Dangerous Arrhythmias During Exercise Tests in Pediatric and Congenital Heart Disease Patients

OBJECTIVES

This study quantified the incidence of arrhythmias during pediatric exercise stress tests (ESTs) and evaluated criteria to identify patients at risk of clinically important arrhythmias.

BACKGROUND

The incidence of clinically important arrhythmias during pediatric ESTs and criteria for identifying high-risk patients are poorly characterized.

METHODS

A retrospective review of ESTs performed from 2013 to 2015 was studied. Arrhythmias were categorized into 4 classes based on need for test termination and intervention. Risk factors evaluated included having an implantable cardioverter-defibrillator (ICD), cardiomyopathy, severe ventricular dysfunction, complex arrhythmia history, coronary disease with concern for ischemia, pulmonary hypertension, select poorly palliated congenital heart disease (CHD), and concerning symptoms. Negative predictive values (NPVs) were calculated.

RESULTS

During the study period, 5307 ESTs were performed. Median age of the subjects was 16 years (interquartile range: 13 to 24 years); 20% had complex CHD. At least 1 high-risk criterion was present in 507 tests (10%); having an ICD (37%) and cardiomyopathy (36%) were the most common criteria. Some arrhythmias were seen in 46% of tests, but only 33 events (0.6%) required test termination. Three events (0.06%) required cardiopulmonary resuscitation, all with high-risk criteria. Absence of a high-risk criterion had a 99.7% (95% confidence interval [CI]: 99.5% to 99.8%) NPV for an arrhythmia that required test termination and a 99.96% (95% CI: 99.85% to 99.99%) NPV for an arrhythmia that required intervention beyond test termination.

CONCLUSIONS

Although self-terminating arrhythmias are common, dangerous arrhythmias are rare during ESTs in a high-volume pediatric cardiology program. Pre-defined high-risk criteria identified all patients with the most serious events. The absence of any criteria predicted a low risk for arrhythmias that required test termination. These data permitted informed choices regarding supervision of ESTs.

Relation of oxygen uptake to work rate in prepubertal healthy children - reference for VO2 /W-slope and effect on cardiorespiratory fitness assessment

PURPOSE

Exercise testing by cycle ergometer allows to observe the interaction between oxygen uptake (VO₂ ) and workload (W), and VO₂ /W-slope can be used as a diagnostic tool. Respectively, peak oxygen uptake (VO_2PEAK ) can be estimated by maximal workload. We aim to determine reference for VO₂ /W-slope among prepubertal children and define agreement between estimated and measured VO_2PEAK .

METHODS

A total of 38 prepubertal children (20 girls) performed a maximal cycle ergometer test with respiratory gas analysis. VO₂ /W-slopes were computed using linear regression. Agreement analysis by Bland and Altman for estimated and measured VO_2PEAK was carried out including limits of agreement (LA). Determinants for VO₂ /W-slopes and estimation bias were defined.

RESULTS

VO2/W-slope was in both girls and boys ≥9·4 and did not change with exercise level, but the oxygen cost of exercise was higher among physically more active children. Estimated VO_2PEAK had 6·4% coefficient of variation, and LA varied from 13% underestimation to 13% overestimation. Bias had a trend towards underestimation along lean mass proportional VO_2PEAK . The primary determinant for estimation bias was VO2/W-slope (β = -0·65; P<0·001).

CONCLUSION

The reference values for VO₂ /W-slope among healthy prepubertal children were similar to those published for adults and among adolescents. Estimated and measured VO_2PEAK should not be considered to be interchangeable because of the variation in the relationship between VO₂ and W. On other hand, variation in the relationship between VO₂ and W enables that VO₂ /W-slope can be used as a diagnostic tool.

[Exercise testing: New guidelines]

The GERS (Exercise Rehabilitation and Sports Group of the French Society of Cardiology) has decided to update current guidelines regarding the practice of EKG stress tests. Since the last update dates from 1997, the GERS judged it necessary to integrate data from new works and advancements made in the last 20 years. Good clinical practices and safety conditions are better defined regarding the structure, location, material, staff competency, as well as convention with hospital structures. The diagnosis of coronary artery disease remains the principal indication for a stress test. Interpretation of the results is crucial-it must be multivariate and provide either a low, intermediate or strong probability of the existence of coronary lesions, taking into account the studied population (risk factors, age, sex and symptoms). Several new indications for a stress test have been defined for the assessment of cardiac pathologies. With such indications, the use of gas expiration measurements is highly recommended in order to provide a precise prognosis for all the various cardiac pathologies : congenital, ischemic, valvular, cardiomyopathies, congestive heart failure, rhythm and conduction disorders, pacemaker fine-tuning, or pulmonary hypertension. Indications for stress tests and contraindications are defined according to different population subgroups, for instance : athletes, women, children, the elderly, asymptomatic patients, diabetics, hypertensive patients, PAD patients, or in the context of a non-cardiac surgery pre-op visit. The new guidelines (due for publication soon) are considerably different from those dating from 1997 and further pinpoint the relevance and importance of an EKG stress test within the arsenal of complementary cardiologic exams. With the improvements made in providing diagnostic value in CAD, as well as better prognostic value for any underlying pathology, the indication for an EKG stress test has extended to all cardiovascular disease.

Feasibility of exercise stress echocardiography and myocardial response in patients with repaired congenital heart disease

BACKGROUND

Exercise stress echocardiography (ESE) can unmask ventricular dysfunction in asymptomatic patients with congenital heart disease (CHD), but its acquisition and interpretation is often challenging, and the method has not been validated in CHD. This study aimed to evaluate the feasibility of ESE using Doppler imaging and to assess myocardial response to exercise in patients with biventricular (BiV) and univentricular (UniV) circulation after CHD repair.

METHODS

In this single-center prospective study, we recruited 55 participants (17 females), median age 14 years (8-22 years). Our analysis categorized participants in these three groups: with structurally normal hearts as controls (n=21), with BiV circulation (n=20) and with UniV circulation (n=14). We acquired ESE images of the systemic ventricle including pulsed-wave flow and spectral tissue Doppler imaging (TDI) of lateral free wall before and immediately after standard, symptom-limited exercise tests on an electronically braked cycle ergometer.

RESULTS

During ESE we obtained inflow E-wave and TDI systolic (S') and early diastolic (E') velocities in 93% to 100% of participants at rest and in 90% to 100% of participants post exercise. Feasibility to obtain Doppler imaging parameter was the same across study groups. The myocardial response to exercise was increase in heart rate (HR), S' and inflow E-wave velocity in all participants. Patients with BiV circulation had preserved ventricular function at rest. While patients with UniV circulation had low S', E', and E-wave velocities at rest in comparison to controls and to BiV group (all P<.001), both patients with BiV and UniV circulation showed significant increases in HR, S' velocity and inflow E-wave velocity post exercise, with magnitudes of these increases higher in controls than in the BiV and UniV group. The S' and E' velocities were strongly associated with lower percent predicted peak oxygen consumption VO₂ (r_s=0.614 and r_s=0.64, respectively, both P<.001).

CONCLUSION

ESE with Doppler imaging is a practical noninvasive diagnostic method and sufficiently robust for the assessment of morphologic LV/systemic ventricles under exercise in patients after biventricular and univentricular CHD repair. Although patients with BiV and UniV circulation had both preserved myocardial response to exercise, the magnitude of this response was the lowest in patients with UniV circulation.

[Sports in children with congenital heart diseases]

The practice of physical activity is one of the essential elements for health in general but also for the well-being and the quality of life. It is highly desirable to encourage physical activities in children with congenital heart diseases, taking into account all the benefits associated with this practice (quality of life, life expectancy) and this especially since these children often have limited capacity (due to their heart disease but also often by relative deconditioning). While there is a transient increase in risk of cardiac complications during intense activity, it would nevertheless be inappropriate to contra-indicate physical activities considering the well-known benefits in the medium and long term. The risks associated with the practice of physical activity must be assessed, on one hand, in terms of the severity of the heart disease, and on the other hand, on the nature and intensity of the activity. The stress test is here an essential tool because it helps to assess the physical capacity and cardiorespiratory adaptations to exercise. The international recommendations for competitive sports generally give an appropriate advice for a specific situation but the practice of moderate activity or leisure sports which are highly desirable should not be neglected and be strongly encouraged.

A randomised controlled trial of adjunctive yoga and adjunctive physical exercise training for cognitive dysfunction in schizophrenia

BACKGROUND

Yoga and physical exercise have been used as adjunctive intervention for cognitive dysfunction in schizophrenia (SZ), but controlled comparisons are lacking. Aims A single-blind randomised controlled trial was designed to evaluate whether yoga training or physical exercise training enhance cognitive functions in SZ, based on a prior pilot study.

METHODS

Consenting, clinically stable, adult outpatients with SZ (n=286) completed baseline assessments and were randomised to treatment as usual (TAU), supervised yoga training with TAU (YT) or supervised physical exercise training with TAU (PE). Based on the pilot study, the primary outcome measure was speed index for the cognitive domain of 'attention' in the Penn computerised neurocognitive battery. Using mixed models and contrasts, cognitive functions at baseline, 21 days (end of training), 3 and 6 months post-training were evaluated with intention-to-treat paradigm.

RESULTS

Speed index of attention domain in the YT group showed greater improvement than PE at 6 months follow-up (p<0.036, effect size 0.51). In the PE group, 'accuracy index of attention domain showed greater improvement than TAU alone at 6-month follow-up (p<0.025, effect size 0.61). For several other cognitive domains, significant improvements were observed with YT or PE compared with TAU alone (p<0.05, effect sizes 0.30-1.97).

CONCLUSIONS

Both YT and PE improved attention and additional cognitive domains well past the training period, supporting our prior reported beneficial effect of YT on speed index of attention domain. As adjuncts, YT or PE can benefit individuals with SZ.

Rehabilitación cardiaca en pediatría: ¿qué dice la evidencia?

Introducción. En las últimas cuatro décadas, las organizaciones de la salud han reconocido que la rehabilitación cardíaca es un elemento esencial para la recuperación de pacientes con enfermedades cardiovasculares.Objetivo. Realizar un análisis de la evidencia sobre la implementación de un programa de rehabilitación cardiaca, basado en ejercicio físico, en una población pediátrica con alteraciones congénitas cardiacas.Materiales y métodos. Se buscó y analizó la evidencia disponible de programas de rehabilitación cardiaca, basada en ejercicio físico, en pacientes pediátricos con alteraciones congénitas. Para la búsqueda se emplearon los términos MeSH: “Rehabilitation”, “Exercise”, “Resistance Training” y “Pediatrics” y se hizo revisión en las bases de datos Ebsco, Pedro, Hinari, Elsevier, Science Direct, Springer y Medline.Resultados. Se encontró que la implementación de un programa de rehabilitación cardiaca en población pediátrica tiene resultados significativos en la calidad de vida de estos pacientes, pero necesita de parámetros como evaluación, protocolo de rehabilitación, prescripción del ejercicio físico y evaluación de la calidad de vida.Conclusiones. Es necesario crear un protocolo estandarizado y validado de rehabilitación cardiaca, basada en ejercicio físico, para la población pediátrica con enfermedades cardiacas congénitas.

Effects of Ramadan intermittent fasting on North African children's heart rate and oxy-haemoglobin saturation at rest and during sub-maximal exercise

Aim:

To examine the effects of Ramadan intermittent fasting (RIF) on the heart rate (HR) and oxyhaemoglobin saturation levels (oxy-sat) of boys at rest and during a six-minute walking test (6MWT).

Methods:

Eighteen boys (age: 11.9 ± 0.8 years, height: 153.00 ± 8.93 cm, body mass: 55.4 ± 18.2 kg), who fasted the entire month of Ramadan in 2012 for the first time in their lives, were included. The experimental protocol comprised four testing phases: two weeks before Ramadan (pre-R), the end of the second week of Ramadan (R-2), the end of the fourth week of Ramadan (R-4), and 10 to 12 days after the end of Ramadan (post-R). During each phase, participants performed the 6MWT at approximately 15:00. HR (expressed as percentage of maximal predicted HR) and oxy-sat (%) were determined at rest and in each minute of the 6MWT.

Results:

R-4 HR values were lower than those of (1) pre-R (in the second minute), (2) R-2 (in the first and second minutes), and (3) post-R (in the first, second, fourth, fifth and sixth minutes). R-2 oxy-sat values were higher than those of pre-R (in the third minute) and those of post-R (in the fifth minute). Post-R oxy-sat values were lower than those of pre-R and R-4 in the fifth minute. These oxy-sat changes were not clinically significant since the difference was less than five points.

Conclusion:

In non-athletic children, their first RIF influenced their heart rate data but had a minimal effect on oxy-sat values.

Cardiorespiratory fitness, respiratory function and hemodynamic responses to maximal cycle ergometer exercise test in girls and boys aged 9-11 years: the PANIC Study

PURPOSE

We aimed to provide comprehensive data on and reference values for cardiorespiratory fitness, respiratory function and hemodynamic responses during and after maximal cycle ergometer test in children.

METHODS

The participants were a population sample of 140 children (69 girls) aged 9-11 years. Heart rate (HR) and systolic blood pressure (SBP) were measured from pre-exercise rest to the end of recovery. Respiratory gases were measured directly by the breath-by-breath method. Peak workload, HR changes, peak oxygen uptake (VO2), peak oxygen pulse (O2 pulse), peak respiratory exchange ratio (RER) and the lowest ratio of ventilation and carbon dioxide output (VE/VCO2) during the exercise test in girls and boys were presented according to their distributions in 5 categories.

RESULTS

HR decreased more during 4-min recovery in boys than in girls (76 vs. 67 beats/min, p < 0.001), whereas SBP decrease was similar in boys and girls (30 vs. 22 mmHg, p = 0.66). Boys had a higher peak VO2 per weight [51.9 vs. 47.6 ml/kg/min, p < 0.001] and per lean mass [67.3 vs. 63.0 ml/kg/min, p < 0.001] than girls. Peak O2 pulse per lean mass was higher in boys than in girls (0.34 vs. 0.31 ml/kg/beat, p < 0.001). There was no difference in the lowest VE/VCO2 during the test between boys and girls (28 vs. 29, p = 0.18).

CONCLUSIONS

The indicators of cardiorespiratory fitness were better in boys than in girls. These data enable the evaluation of cardiorespiratory function during and after maximal exercise test and the detection of children with abnormal values.