First Real-Life Data on the Diving Response in Healthy Children.

Swimming and diving are popular recreational activities, representing an effective option in maintaining and improving cardiovascular fitness in healthy people. To date, only little is known about the cardiovascular adaption to submersion in children. This study was conducted to improve an understanding thereof. We used a stepwise apnea protocol with apnea at rest, apnea with facial immersion, and at last apnea during whole body submersion. Continuous measurement of heart rate, oxygen saturation, and peripheral resistance index was done. Physiologic data and analysis of influencing factors on heart rate, oxygen saturation, and peripheral vascular tone response are reported. The current study presents the first data of physiologic diving response in children. Data showed that facial or whole body submersion leads to a major drop in heart rate, and increase of peripheral resistance, while the oxygen saturation seems to be unaffected by static apnea in most children, with apnea times of up to 75 s without change in oxygen saturation.

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

BACKGROUND: Complex CHDs are life threatening, and surgical treatment is needed for survival. Fontan palliation led to a significant increase in survival rates during the last decades. Consequently, quality of life became more essential. While a reduced quality of life compared to healthy children has been reported, detailed knowledge about individual quality of life and particular areas is lacking. Furthermore, the effect of different risk factors on quality of life is only rarely evaluated. METHOD AND RESULTS: Database of the department for pediatric cardiology, Heart Center Leipzig, was screened for children after total cavopulmonary connection palliation. n = 39 patients were included in the study, the outcome after total cavopulmonary connection was analysed in detail and quality of life data were collected and analysed using the standardised questionnaire "Pediatric quality of life inventory", version 4.0. We compared the total health score of our patients to the mean score of healthy children in the literature. The mean follow-up time was 6.4 ± 3.2 years, the overall survival was 100% after maximal follow-up time of 11.1 years. We could not find any age or gender dependence, nor an influence of age at total cavopulmonary connection on the later quality of life. Yet, patients with three-staged surgery exhibited a worse quality of life than patients with two-staged palliation. Late complications might influence quality of life, but patient number is too small, to find universal results. CONCLUSION: The total cavopulmonary connection palliation affects physical and psychological quality of life as well as cardiac health independently from age and gender. More patients and longer observation should be examined to confirm the results.

Coherent mapping of atrial tachycardias in patients with congenital heart disease.

AIMS: Coherent mapping (CM) uses a new algorithm to identify critical conduction isthmuses of atrial tachycardias (ATs). We analysed our experience of ablation of AT in patients with congenital heart disease (CHD) with this new technology. METHODS AND RESULTS: All patients with CHD who had CM of AT using the high-density mapping PENTARAY™ catheter and three-dimensional electroanatomic mapping system Carto3 between June 2019 and June 2021 were included retrospectively (n = 27). As a control group, 27 patients with CHD and mapping of AT without CM between March 2016 and June 2019 were included. In total, 54 ablation procedures were performed in 42 patients [median age 35 (interquartile range, IQR 30-48) years] and 64 ATs were induced and mapped (thereof 50 AT intraatrial re-entrant tachycardia and 14 AT ectopic AT). The median procedure duration was 180 (120-214) min and median fluoroscopy time was 10 (5.2-14) min. Acute success was 100% (27/27) in the Coherence group and 74% (20/27) in the non-Coherence group (P = 0.01). During follow-up [median 26 (12-45) months], AT recurred in 28/54 patients, thereof 15 patients needed a re-ablation procedure. Log-rank test showed no difference in recurrence rate between the two groups (P = 0.29). Three minor complications occurred (5.5%). CONCLUSION: Mapping of AT in patients with CHD using the PENTARAY™ mapping catheter and the CM algorithm led to excellent acute success. All ATs were possible to map and no complications related to the PENTARAY™ mapping catheter were observed. Thus, the use of the CM algorithm represents a promising tool in patients with CHD and complex AT.

Use of the Apple Watch iECG in adult congenital heart disease patients.

INTRODUCTION: This study evaluates the accuracy of iECGs in comparison to the gold standard ECG in adult patients with congenital heart disease and recommends the appropriate iECG derivation based on the patient's characteristics. METHODS: In 106 adults (51 female, 55 male) with congenital heart disease, a gold standard 12-lead ECG was recorded, followed by three iECGs with the Apple Watch series 4, which correspond to Einthoven leads I, II, and III. Two experienced and independent cardiologists analyzed the time intervals, amplitudes, and polarities of the ECG parameters as well as the rhythm type and correlated the patient characteristics with the iECG parameters. RESULTS: The iECG parameters of all three iECG leads correlate strongly with those of the gold standard ECG, with exception of the P and T wave durations. We demonstrated that the informative value of the individual iECGs was independent of the patient's characteristics, in particular the heart axis, anatomy, and situs, even if the quality of the Einthoven III-like derivation was partially inadequate. The automatic rhythm analysis of the Apple Watch and the heart rhythm classification of a standard ECG analyzed manually by a cardiologist corresponded in 77%. CONCLUSION: iECG recordings of adults with congenital heart disease provide comparable results with Einthoven recordings I, II, and III of the 12-lead ECG and current data encourage the use of the Apple Watch not only in patients with structurally normal hearts but also in patients with congenital heart disease.

Accuracy of the Apple Watch single-lead ECG recordings in pre-term neonates.

INTRODUCTION: Telemedicine gained an increasing use throughout the last years. Lifestyle tools like the Apple watch seem to have an increasing spread even in remote areas and underdeveloped regions. The increasing availability of these tools offers the chance to use the health care functions of these devices to improve provision of professional medical care. First data on the use of the Apple Watch as a remote monitoring device in children have been reported, showing good acceptability and usability of the Apple Watch for symptom monitoring in children. This study aimed to evaluate the accuracy of the Apple Watch iECG in comparison to a standard 12-lead ECG in pre-term babies. METHODS: In this prospective, single-arm study, consecutive preterm neonates hospitalised in Leipzig University Hospital neonatal ICU were eligible. A 12-lead ECG and an iECG using Apple Watch 4 were performed. iECG and 12-lead ECG measurements were performed by a paediatric cardiologist. Cardiac rhythm was classified and amplitudes and timing intervals were analysed for comparability. RESULTS: Fifty preterm neonates, gestational week (23-36 weeks), and body weight (0.65-3.09 kg) were enrolled. Overall good quality and excellent correlation of the Apple Watch generated iECG in comparison to the standard 12-lead ECG could be demonstrated (p < 0.001). When interpreted by a paediatric cardiologist, a correct rhythm classification could be done in 100% of cases. CONCLUSION: The Apple Watch iECG seems to be a valuable tool to record an ECG comparable to lead I of the standard 12-lead ECG even in pre-term neonates. With a widespread availability and excellent connectivity, the Apple Watch iECG function may provide practitioners with a tool to send an iECG for interpretation to a paediatric cardiac specialist.

Evaluation of Clinical Course and Maintenance Drug Treatment of Supraventricular Tachycardia in Children During the First Years of Life. A Cohort Study from Eastern Germany.

Supraventricular tachycardia (SVT) is considered the most common cause of arrhythmia in children and infants. Regarding the likelihood of a spontaneous resolution of SVTs during the first years of life, drug treatment aims to bridge the time until children 'grow out' out of the arrhythmia. The choice of antiarrhythmic agents and the planning of maintenance therapy are mainly based on clinical experience and retrospective single- and multi-institutional analyses and databases from all over the world approaching differently to this topic. The current study aimed to evaluate the clinical course, pharmacological treatment strategies, and constellations of risk for recurrences in the management of SVTs in children aged 3 < years. The database of the Heart Center Leipzig, Department of Pediatric cardiology, was searched for pediatric patients aged < 3 years with a clinically documented SVT between 2000 and 2019 that received pharmacologic treatment. Patients with complex congenital heart disease or arrhythmias following cardiac surgery were excluded. 69 patients were included. Pharmacologic treatment, follow-up schedule, recurrences, outcomes, and risk factors for complicated courses are reported. Drug therapy of SVTs in young children remains a controversial topic with heterogeneous treatment and follow-up strategies applied. Risk factors for recurrences and/or stubborn clinical courses are difficult rhythm control with 3 or more antiarrhythmic drugs, ectopic atrial tachycardias, and a first occurrence of the SVT in the fetal period. Prospective studies are needed to sufficiently evaluate optimal treatment strategies.

Open field stress testing: finally an optimal method in young children? Reference values for mobile cardiopulmonary exercise testing in healthy children aged 4-8 years.

INTRODUCTION: Cardiopulmonary exercise testing represents the diagnostic tool for determining cardiopulmonary function. Especially in small children, exercise testing is extremely challenging. To address this problem, field testing has been implemented using small mobile devices. This study aims at using this protocol for developing normal values for cardiopulmonary exercise testing in very young children. MATERIAL AND METHODS: Healthy children aged 4-8 years were recruited. All children were tested according to an outdoor protocol, in which they were instructed to walk, then run slowly, then a little harder and at last run at full speed. Each step lasted for 2 minutes, except the last step, in which the children were instructed to maintain as long as possible. RESULTS: A total of 104 children (64 female/35 male, mean age 6.6 years) performed outdoor cardiopulmonary exercise testing using a mobile device. Almost all tests were completed successfully (95%). Despite a predominance of female study subjects, anthropometric values did not differ between boys and girls. V̇O2peak/kg, respiratory exchange ratio, VT1, heart rate at VT1, and time of exercise were also comparable between sexes. Generally, a tendency of higher maximal oxygen uptake could be observed in older children. CONCLUSION: Open field mobile cardiopulmonary exercise testing represents a novel approach in very young children. In this study, we were able to determine normal values of maximal oxygen uptake and OUES/kg for 4-8-year-old children. The method is easy to achieve and safe.

Does obesity have an effect on the ECG in children?

This review summarizes current data on influences of childhood obesity on the 12-lead electrocardiogram (ECG). Studies on obese adults showed a higher risk of cardiovascular complications and also, partly pathological, ECG alterations. Data on ECG alterations in obese children is rare. In current studies, no pathological findings were found. All alterations, which mimic the later pathological phenomena in obese adults, were within normal ranges. Studies reported significantly longer P-wave time and P-wave dispersion (Pd) in obese children [Üner A, Dogan M, Epcacan Z, Epçaçan S. The effect of childhood obesity on cardiac functions. J Pediatr Endocr Met 2014;27:261-71.], no correlation of heart rate, P-wave, or QT dispersions (QTd) [Akyüz A, Alpsoy S, Akkoyun DC, Nalbantoǧlu B, Tülübaș F, et al. Effect of overweight on P-wave and QT dispersions in childhood. Turk Kardiyol Dern Ars 2013;41:515-21.], significantly higher QTd in obese children [Yildirim S, Binnetoglu FK, Battal F, Aylanc H, Nazan Kaymaz N, et al. Relation between QT variables and left ventricular geometry in athletes and obese children. Acta Med Port 2016;29:95-100.], no significant association between obesity and QTc interval (QTc), but longer PR intervals, wider QRS duration and left axis shifting of frontal P-wave, QRS and T-wave axes [Sun G, Li Y, Zho X, Guuo X, Zhang X, et al. Association between obesity and ECG variables in children and adolescents: a cross-sectional study. Exp Ther Med 2013;6:1455-62.], significant prolongation of QTc, T peak-to-end, and QTd in the obese children [Paech C, Liebold A, Gebauer RA, Wagner F, Vogel M, et al. Relative QT interval prolongation and electrical inhomogeneity of cardiac repolarization in childhood obesity. Prog Pediatr Cardiol 2017;47:64-7.], slight shift to the left in the QRS axis (with no changes in the P axis), increased amplitudes of the left-sided leads in obese children, and no correlation of the heart rate with the weight [Paech C, Anhalt M, Gebauer RA, Wagner F, Vogel M, et al. New normal limits for pediatric ECG in childhood obesity? Influence of childhood obesity on the ECG. Prog Pediatr Cardiol 2018;48:119-23.]. Altogether, the study results are inconsistent. Clearly, pathological phenomena in the ECG of obese children were not reported: only preliminary stages like QTc prolongation within the norm were found. The pathological alterations seen in adult obese patients are not (yet) seen in childhood. The slight changes reported in childhood obesity are likely to manifest later and to develop into pathological phenomena in obese adults and, therefore, might increase the risk of cardiovascular events like arrhythmia and sudden cardiac death in adulthood.