Introduction: Syncope is one of the most common reasons for seeking medical attention in the pediatric population. The underlying etiology ranges from benign causes to potentially life-threatening conditions. Objective: This cross-sectional retrospective study aimed to cardiologically evaluate children presenting with syncope and identify potential predictive parameters for cardiogenic syncope, the most dangerous type of syncope. Patients and Methods: Data from 100 children aged 6 to 18 years who presented with syncope were retrospectively collected from medical records at the Pediatric Clinic of the Clinical Center of the University of Sarajevo between January 1, 2021, and December 31, 2022. Binary logistic regression was used to examine the predictive significance of the studied parameters. Results: Of the 100 children with documented syncope, 71.0% were girls, with the peak incidence of syncope episodes occurring at age 15. There were no statistically significant differences in height, weight, or BMI between boys and girls. The most common cardiac diagnosis was sinus arrhythmia, while headache was the most frequent non-cardiac symptom. Seventy-three percent of patients experienced more than one syncope episode, with the highest percentage occurring at school. Prodromal symptoms were present in 87% of cases, whereas palpitations and chest pain prior to syncope were reported in 10% and 12% of cases, respectively. Among the 49 patients with abnormal ECG findings, 29% had sinus arrhythmia and 25% had incomplete right bundle branch block. The most common echocardiographic finding was mild pulmonary valve regurgitation, which is considered a physiological variant. Of all studied parameters, only EEG demonstrated significant predictive value for cardiogenic syncope (p = 0.035, EXP(B) = 2.99). Conclusion: EEG findings have predictive significance for cardiogenic syncope in children. A borderline EEG increases the odds of cardiogenic syncope by approximately threefold.

BACKGROUND: Left atrial strain (LAS) analysis represents a newer non-invasive, sensitive and specific technique for assessing left atrial (LA) function and early detection of its deformation and dysfunction. However, its applicability in mitral regurgitation (MR) in pediatric population remains unexplored, raising pertinent questions regarding its potential role in evaluating the severity and progression of the disease. OBJECTIVE: To investigate the impact of chronic MR in children and adolescents on LA remodeling and function. METHODS: The study included 100 participants. Patients with primary and secondary chronic MR lasting at least 5 years fit our inclusion criteria. The exclusion criteria from the study were: patients with functional mitral regurgitation due to primary cardiomyopathies, patients with artificial mitral valve, patients with MR who had previously undergone surgery due to obstructive lesions of the left heart (aortic stenosis, coarctation of the aorta), patients with significant atrial rhythm disorders (atrial fibrillation, atrial flutter). The echocardiographic recordings were conducted by two different cardiologists. Outcome data was reported as mean and standard deviation (SD) or median and interquartile range (Q1–Q3). RESULTS: The study included 100 participants, of whom 50 had MR and the remaining 50 were without MR. The average age of all participants was 15.8 ± 1.2 years, with a gender distribution of 37 males and 63 females. There was a significant difference in the values of LA volume index (LAVI), which were higher in patients with MR ( p = 0.0001), S/D ratio (and parameters S and D; p = 0.001, p = 0.0001, p = 0.013), mitral annulus radius ( p = 0.0001), E/A ratio ( p = 0.0001), as well as septal e’ (m/s), lateral e’ (m/s), and average E/e’ ratio, along with the values of TV peak gradient and LV global longitudinal strain (%). There was no significant difference in LA strain parameters, nor in LA stiffness index (LASI). CONCLUSION: Our findings revealed significant differences in several echocardiographic parameters in pediatric patients with MR relative to those without MR, providing insight into the multifaceted cardiac structural and functional effects of MR in this vulnerable population.

BACKGROUND: Left atrial stiffness index (LASI), defined as the ratio of early diastolic transmitral flow velocity/lateral mitral annulus myocardial velocity (E/e’) to peak atrial strain, reflects reduced left atrial (LA) compliance and represents an emerging marker that can be used for noninvasive measurement of fibrosis of LA in patients with mitral regurgitation (MR). OBJECTIVE: To investigate the impact of chronic MR in children and adolescents on the remodeling and function of the LA, quantified through strain parameters and diastolic function. METHODS: The study included fifty patients ( n = 50) diagnosed with primary and secondary chronic MR lasting at least 5 years. The echocardiographic recordings were performed by a third party, two cardiologists actively engaged in echocardiography on a daily basis. RESULTS: Older participants had higher values of the LASI ( r = 0.467, p = 0.001). Participants with higher LASI values had a smaller LA reservoir ( r = 0.784, p = 0.0001) and smaller LA conduit values ( r = - 0.374, p = 0.00). Participants with higher LASI values had a larger LA diameter ( r = 0.444, p -value= 0.001) and higher average E/e’ ratio ( r = 0.718, p = 0.0001). There was a significant difference ( p = 0.04) in the LASI among participants based on the MR jet area ( < 20.85% ⩾ 20.85%), LASI was higher in participants with an area greater than 20.85%. Differences in other parameters such as LA reservoir, LA conduit, LA contractile were not statistically significant. CONCLUSION: Increased LA stiffness is associated with diminished atrial compliance and reservoir capacity, and LASI has a potential to as an early marker for assessing disease severity and progression in pediatric MR.

Over the last few years, remarkable progress has been made in the field of congenital heart diseases. Improvements considering diagnostic modalities, especially imaging, in surgical and interventional techniques, as well as in postoperative therapy and care, have contributed to a significant reduction in mortality and morbidity. One of the most important applications of medical imaging techniques in children is the detection and treatment of congenital heart anomalies. Objective of this article is to show the importance of ultrasonography in the detection of congenital heart diseases in children. The study was conducted on children with simple and complex congenital heart diseases and was conducted on the Pediatric Clinic, UKCS. The research is descriptive on a representative sample. In our study, 166 children were observed, of which 148 children (77 boys, 71 girls) with simple congenital heart diseases, and 18 children (8 boys, 10 girls) with complex congenital heart diseases. Out of the total number of observed children, 115 had a surgical correction, 97 children with simple congenital heart diseases (45 boys, 52 girls) and 18 children with complex congenital heart diseases (8 boys, 10 girls). The number of children monitored through the Cardiac Counseling Center who didn’t undergo surgical correction was 51, all with simple congenital heart diseases. Out of the total number of observed children who were frequently coming for follow-ups, 28 children had changes on the ECG, and 138 of them had no changes on the ECG, 93 were surgically treated, and 73 of them were on conservative therapy. Based on the results of the research, we conclude that ultrasonography is an important method in the detection and treatment of congenital heart diseases.

Pediatric arrhythmology deals with studying of frequency and regularity of heart rhythm disorders in childhood. Rhythm disturbances (dysrhythmias, arrhythmias) occur as a result of disturbances in the creation or conduction of stimuli in the specific or working musculature of the heart. Simplifying the knowledge of everyday work on pediatric arrhythmias, they can originate from the atria of the heart when we speak about supraventricular arrhythmias or from the heart chambers when we talk about ventricular arrhythmias. There are currently three major problems that burden pediatric cardiologists and pediatric arrhythmologists, and which are the focus of interest in pediatrics as a whole. These are primarily sudden cardiac death in children (SCD), fetal arrhythmias (FA) and postoperative-incisional arrhythmias (IA). The development of pediatric arrhythmology is imperative in the development of pediatrics and pediatric cardiology.

BACKGROUND: Left atrial (LA) strain analysis has emerged as a noninvasive technique for assessing LA function and early detection of myocardial deformation. Recently, its application has also shown promise in the pediatric population, spanning diverse cardiac conditions that demand accurate and sensitive diagnostic measures. OBJECTIVE: This research article endeavors to explore the role of LA strain parameters and contribute to the growing body of knowledge in pediatric cardiology, paving the way for more effective and tailored approaches to patient care. METHODS: A comprehensive literature review was conducted to gather evidence from studies using echocardiographic strain imaging techniques across pediatric populations. RESULTS: LA strain parameters exhibited greater sensitivity than conventional atrial function indicators, with early detection of diastolic dysfunction and LA remodeling in pediatric cardiomyopathy, children with multisystem inflammatory syndrome, rheumatic heart disease, as well as childhood renal insufficiency and obesity offering prognostic relevance as potential markers in these pediatric subpopulations. However, there remains a paucity of evidence concerning pediatric mitral valve pathology, justifying further exploration. CONCLUSION: LA strain analysis carries crucial clinical and prognostic implications in pediatric cardiac conditions, with reliable accuracy and sensitivity to early functional changes.

Aim Compare the efficacy of nebulized hypertonic saline and normal saline in the treatment of infants hospitalized for bronchiolitis. Methods This retrospective study was conducted at the Department of Pulmonology, Paediatric Clinic, Clinical Centre University of Sarajevo, covering the period from January 2015 to December 2019 and comprising 380 children aged between 1 and 12 months having bronchiolitis. One group received nebulized hypertonic saline (NHS, 3% NaCl)), and another group received nebulized normal saline (NNS, 0.9% NaCl). The control group did not receive any of these treatment options. Results There was no statistically significant difference between the treatment groups regarding length of hospital stay (LOS) and Clinical Severity Score (CSS) at admission and discharge as well as in oxygen therapy duration and antibiotic use, the duration of symptoms before hospital admission, frequency of nasal discharge, elevated temperature, dyspnoea, cough and dehydration. Conclusion The results of this study are consistent with several recent studies or meta-analyses and support the evidence against the use of NHS in hospitalized infants with mild or moderate bronchiolitis.

Aim To analyse the association of human leukocyte antigen B27 with clinical and laboratory parameters in patients with juvenile idiopathic arthritis (JIA) at the disease onset. Methods A retrospective review of medical records of 25 HLAB27 positive and 25 HLA-B27 negative JIA patients was performed. The diagnosis of JIA was based on the 1997-2001 International League Against Rheumatism (ILAR) criteria. Collected data: age, sex, HLA- B27 antigen presence, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), rheumatoid-factor (RF), antinuclear antibody (ANA), fever, rash, uveitis, enthesitis, inflamed joints and subtype of JIA. Results HLA- B27 positive study group had more boys (p=0.01), higher erythrocyte sedimentation rate (p=0.038), higher presence of fever (p= 0.025) and enthesitis (p=0.024). Any significant difference in age of the disease onset, CRP, ANA, RF, rash, uveitis, inflamed joint and dactylitis was not noticed. The most common subtype of JIA in the HLA-B27 positive patients was ERA (60%). Conclusion This study showed that the presence of HLA- B27 antigen plays a significant role in determining the presenting clinical and laboratory characteristics in JIA patients.

Abstract Aim: The study aimed to evaluate the acute effect of ultrafiltration on the mechanical properties of the aorta using brachial-ankle pulse wave velocity (PWV) before and after hemodialysis (HD). Patients and Methods: This study included 80 patients who were on a long-term HD program. The input variables were anamnestic data, body composition monitor (BCM) parameters, and echocardiography findings. The assessment of hydration status was determined by BCM, whose work is based on the principle of multifrequency bioimpedance spectroscopy. Another diagnostic procedure was the use of an arteriograph apparatus to assess PWV and Augmentation Index (AIx). All measurements were performed before and after dialysis on the middle dialysis day of the week. Results: The participants were divided into two groups based on hydration status: the experimental group consisted of 40 overhydrated participants and the control group consisted of 40 normovolemic participants. Statistically, the following BCM parameters correlated significantly positively with PWV: total body fat (r = 0.222; P < 0.05), overhydration (r = 0.290; P < 0.001), and relative overhydration (r = 0.290; P < 0.001). From echocardiography findings, only left atrial diameter correlated statistically significantly positively with PWV (r = 0.359; P < 0.001). Comparison of the mean PWV values within the experimental group before and after HD showed a statistically significant decrease from 14.32 ± 2.34 m/s to 8.72 ± 1.52 m/s (Z = 3.254; P = 0.0001). Mean PWV values within the control group did not decrease significantly from 13.39 ± 1.32 m/s to 10.39 ± 1.18 m/s (Z = 0.524; P = 0.742). If we compare the mean values of PWV between groups, then before HD treatment, there was no statistically significant difference between groups with PWV values in the experimental group of 14.32 ± 2.34 m/s and the control group of 13.39 ± 1.32 m/s (Z = 0.762; P = 0.852). According to the results of univariate regression analysis before and after HD treatment, only overhydration showed an absolute effect on PWV before and after HD. Conclusion: Overhydration showed an effect on brachial-ankle PWV before and after HD, and brachial-ankle PWV should be followed in HD patients.

The emergence of blockchain technologies, including smart contracts, enables the decentralization of applications that were previously controlled by a single entity. In many cases, however, smart contracts still need to distinguish between different user roles according to their assigned duties. To ensure security, smart contracts often apply a simple form of role-based access control (RBAC), where a dedicated administrator assigns users to roles that are authorized to invoke specific smart contract functions. As this solution contradicts the blockchain principles of decentralization and democratic decision making, smart contracts may also form decentralized autonomous organizations where governance decisions are based on voting by all participants. Many applications would benefit from a hybrid approach that involves roles with different permissions while still allowing for collaborative management. Therefore, we propose a novel mechanism for RBAC administration in smart contracts based on hierarchical roles and configurable administration rules for each role. Any change in the user-role relation requires joint approval by members of selected roles according to the associated rule. This enables decentralized organizational charts with flexible administration constraints, where each role corresponds to specific permissions in the decentralized application and any change is transparently and securely recorded on the blockchain. The practical feasibility of the approach is demonstrated by means of a prototypical implementation for the Ethereum blockchain. Several benchmarks are performed to analyze the potential overhead of different solution variants.

Aim To analyse biochemical markers as possible predictors of death before discharge in cooled newborns following perinatal asphyxia. Methods A total of 91 infants that underwent therapeutic hypothermia after perinatal asphyxia were included. Inclusion criteria for therapeutic hypothermia were Sarnat stage 2 or 3. Data were collected from medical histories regarding gender, gestational age, birth weight, Apgar and Sarnat score; additionally, gas analyses, liver and cardiac enzymes before, and in the first 12 hours after starting therapeutic hypothermia, were evaluated. The patients' characteristics were compared between two groups, survivors and non-survivors. Results Statistical difference was not found between groups regarding gender, gestational age, birth weight, delivery type, 1st and 5th minute Apgar score, seizures, alanine aminotransferase (ALT), creatine kinase (CK), troponin and fibrinogen level. Groups were significantly different regarding acid-base balance (p=0.012), base excess (BE) (p=0.025), lactate (p=0.002), aspartate aminotransferaze (AST), (p=0.011), lactate dehydrogenase (LDH) (p=0.006), activated partial thromboplastin clotting time (aPTT) (p=0.001) and international normalized ratio (INR) (p=0.001). Conclusion Acid-base balance, BE, lactate, AST, LDH, aPTT and INR were significantly higher in the group of cooled newborns after perinatal asphyxia (non-survivors), and can serve as predictors of death before discharge. Combining diagnostic modalities raises a chance for accurate prediction of outcomes of asphyxiated infants.

Aim The aim of this study was to link the values of D-dimer and C-reactive protein (CRP), with the occurrence of pericardial effusion in patients who had coronavirus disease 2019 (COVID-19) and have preserved systolic function of the left ventricle (LV). Methods This was a prospective study and included 146 patients who underwent echocardiographic examination 30 days after the acute phase of COVID-19. Patients who were placed on mechanical ventilation, patients who had pulmonary thromboembolism or acute coronary syndrome during the acute period of the disease, patients who had an ejection fraction of the LV <50%, patients who were diagnosed with pericarditis during acute illness or clinical signs of heart failure (or had elevated N-terminal-pro hormone B-type natriuretic peptide value), with verified renal or hepatic dysfunction were excluded from the study, including patients with diabetes mellitus Type 1, patients with cancer, connective tissue disease, or pregnant women. The existence of cardiovascular risk factors (hypertension, diabetes mellitus Type 2, and hyperlipidemia), the presence of previous ischemic heart disease, maximum values of D-dimer, and CRP (during the first 15 days of the disease) was taken into the analysis. Results Effusion was verified around the right atrium (RA) in 104 patients (3.85 ± 1.75 mm), in 135 patients next to the free wall of the right ventricle (RV) (5.24 ± 2.29 mm), in front of the apex of the LV in 27 patients (2.44 ± 0.97 mm), next to the lateral wall of LV in 35 patients (4.43 ± 3.21 mm), and behind the posterior wall of LV in 30 patients (2.83 ± 1.62 mm). Mean CRP values during the acute phase of the disease were 43.0 mg/L (8.6–76.2 mg/L), whereas D-dimer mean value was 880.00 μg/L (467.00 –2000.00 μg/L). CRP values correlated with effusion next to the free wall of RV (rho = 0.202; P = 0.018). The D dimer correlated with effusion around RA (rho = 0.308; P = 0.0001). Conclusion The clinical picture of the post-COVID patients could be explained by the appearance of pericardial effusion. D-dimer value correlates with the occurrence of effusion around RA, whereas CRP value correlates with effusion next to the free wall of RV.