Multicenter imaging studies are increasingly critical in epidemiology, yet variability across scanners, acquisition protocols, and reconstruction algorithms introduces systematic biases that threaten reproducibility and comparability of quantitative biomarkers. This paper reviews the major sources of heterogeneity in MRI, CT, and PET-CT data, highlighting their impact on epidemiologic inference, including misclassification, reduced statistical power, and compromised generalizability. We outline harmonization strategies spanning pre-acquisition standardization, phantom-based calibration, post-acquisition intensity normalization, and advanced statistical and machine learning methods such as ComBat and domain adaptation. Illustrative examples from MRI flow quantification and radiomic feature extraction demonstrate how harmonization can mitigate site effects and enable robust large-scale analyses.

Interrupted aortic arch (IAA) is a rare congenital cardiovascular anomaly characterized by the absence of continuity between the ascending and descending aorta, often accompanied by congenital heart defects such as ventricular septal defects and patent ductus arteriosus. Accurate preoperative imaging is essential for surgical planning and patient management. This study aimed to compare the diagnostic accuracy of echocardiography and computed tomography angiography (CTA) in evaluating thoracic findings in patients with IAA. A retrospective analysis was conducted on 58 patients (median age: 18 days) diagnosed with IAA between September 2020 and January 2023 at the Heart Center, University Medical Center, Astana, Kazakhstan. Conventional echocardiography and multislice CTA were performed using standardized protocols. Sensitivity, specificity, and other diagnostic performance metrics were calculated. Statistical comparisons were made using McNemar's and Wilcoxon signed-rank tests, with p < 0.05 considered significant. Echocardiography correctly identified 91.4% of IAA cases, while CTA achieved 100% sensitivity and specificity. McNemar's test revealed a significant difference in diagnostic performance favoring CTA (p < 0.05). Measurements of the ascending aorta diameter showed no statistically significant difference between the two modalities (p = 0.09). IAA was predominantly type A (48.3%) and type B (46.6%), with hypoplastic ascending aorta identified in 34.5% of patients. Echocardiography remains a practical initial imaging modality for IAA, offering portability and cost-effectiveness. However, CTA demonstrated superior diagnostic accuracy and anatomical resolution, making it the preferred tool for detailed preoperative evaluation and surgical planning. Future studies with larger cohorts and additional modalities could further refine diagnostic strategies for IAA.

Objective: Atrial fibrillation is strongly associated with stroke and accounts for 60% of cardioembolic stroke. Assessing thromboembolic risk is important for patients with atrial fibrillation. Approximately 90% of all thrombus are localized in the left atrium appendage (LAA). This study aimed to determine the efficacy of cardiac computed tomography (CT) for LAA thrombus detection. Material and methods: This retrospective study included 292 patients. LAA thrombus was confirmed or excluded by cardiac CT with the reference to transesophageal echocardiography (TEE). We excluded patients with allergic reactions to iodide, increased creatinine levels, thyroid disease (hyperthyroidism), pregnancy, and age <18 years. Results: According to the cardiac CT, 103 of 292 people had LAA thrombus, while according to TEE, only 48 of patients had LAA thrombus. The sensitivity and specificity of CT were 97.7% and 77%, respectively. The sensitivity and specificity of the CT was higher in 2016–2020, when the delayed phase was added to the standard protocol, compared to 2012–2015 years. Older age, higher BMI, higher CHA2DS2-VASc and HAS-BLED scores, and larger LA and LVESV were significantly associated with LAA thrombus detection on cardiac CT. Higher LVESV and LVEDV indexes (LVESVI and LVEDVI) and lower LV ejection fraction measured by TEE were also predictors of LAA thrombus detection by cardiac CT. Conclusion: Our findings show that cardiac CT has high sensitivity and specificity for excluding or confirming LAA thrombus, and can also be exclusively used to determine the presence or absence of a thrombus.

BACKGROUND: Tetralogy of Fallot represents 710% of all cases of congenital heart disease, as it occurs in approximately 0.5 per 1,000 live births and is the second most common form of complex congenital heart disease. Advances in diagnosis, surgical techniques, and postoperative treatment have led to an increasing number of patients reaching adulthood, with a dramatic increase in the survival rate to almost 90% at 30 years, thereby creating a need for long-term monitoring of certain anatomic parameters to identify complications in a timely manner. This study aimed to investigate the frequency of computed tomography detected complications after radical correction of Tetralogy of Fallot in pediatric patients. AIM: to identify markers between the most frequency computed tomography detected complications after repair of Tetralogy of Fallot in pediatric patients. MATERIALS AND METHODS: A retrospective analysis was conducted on 613 patients with Tetralogy of Fallot from October 2011 to June 2020. The study included a total of 116 patients (69 men and 47 women) who experienced complications after a repair of Tetralogy of Fallot, as identified by computed tomography. At the time of repair of Tetralogy of Fallot, the patients average age ranged from 10 to 36 months (mean: 12 months), average body weight was 21 kg, average height was 105.4 cm, and average body surface area was 0.74 m2. The patients median age at the time of the computed tomography examination was 17.5 years (age range: 736 years). RESULTS: Among the 116 patients who exhibited complications after an repair of Tetralogy of Fallot, 49 had a pulmonary artery stenosis, 92 had a pulmonary artery branch stenosis (56 of them of the left main pulmonary artery branch, and 36 of them of the right main pulmonary artery branch), 8 had a right ventricular outflow tract stenosis, 32 had a ventricular septal defect, 1 had a shunt thrombosis, 12 had a postoperative deformation of the pulmonary artery, 10 exhibited a marked right ventricular dilatation, 2 had an right ventricular outflow tract aneurysm, and 6 suffered from conduit calcification and stenosis. Moreover, patients with left main pulmonary artery branch stenosis had a 6.5 times greater chance of developing an right main pulmonary artery branch stenosis in (p 0.001). CONCLUSION: The most frequently computed tomography detected complications after a repair of Tetralogy of Fallot were pulmonary artery stenosis and pulmonary artery branch stenosis. Patients with pulmonary artery stenosis and pulmonary artery branch stenosis exhibit no significant differences in terms of age, anthropometric parameters (height, weight, and body surface area), and gender distribution in the presence or absence of different stenosis types (pulmonary artery, right main pulmonary artery branch, or left main pulmonary artery branch). However, an right main pulmonary artery branch stenosis increases the chances of developing an left main pulmonary artery branch stenosis.

Тотальный аномальный дренаж легочных вен (ТАДЛВ) - редкий врожденный порок сердца, диагностируемый лишь у 1% пациентов с подобными аномалиями [2]. Этот порок является серьезным, и лишь немногим новорожденным удается пережить первый год жизни без хирургического вмешательства. При ТАДЛВ легочные вены обычно соединяются с системными венами, правым предсердием или коронарным синусом. Этот дефект может сопровождаться различными другими аномалиями развития сердца, особенно с изомерией предсердий. До эры кардиохирургии большинство детей с ТАДЛВ умирало на ранних стадиях жизни. Прогноз выживаемости у пациентов с необструктивной формой ТАДЛВ обычно более благоприятный, чем у тех, у кого имеется обструктивная форма этого порока [1]. Total anomalous pulmonary venous connection (TAPVC) is a rare congenital heart defect, diagnosed in only 1% of patients with such anomalies [2]. This defect is serious, and only a few newborns manage to survive the first year of life without surgical intervention. In TAPVC, the pulmonary veins typically connect to systemic veins, the right atrium, or the coronary sinus. This defect may be associated with various other heart development anomalies, especially atrial isomerism. Before the era of cardiothoracic surgery, most children with TAPVC died at an early age. The survival prognosis for patients with the nonobstructive form of TAPVC is usually more favorable than for those with the obstructive form of the defect [1]. Өкпе көк тамырларының тұтас аномалиялық дренажы туа біткен жүрек ақаулары бар науқастардың тек 1%- ында кездесетін сирек туа біткен жүрек аномалиясы [2]. Жаңа туылған нәрестелердің өмірінің бірінші жылынан кейін операциясыз өмір сүруі қауіпті аномалия болып табылады және бұл аномалияда өкпенің барлық көк түбіжүйелік тамырлармен байланысты, оң жақ атриум немесе коронарлық синус октадасы жүректіңкең ақауларымен байланысты болуы мүмкін, әсіресе атриальды атрезия.ӨКТАД бар балалардың көпшілігі өмірінің алғашқы бірнеше айында жүрекке операция жасалмас бұрын қайтыс болды. Обструктивті ӨКТАД типті науқастарда өмір сүру ұзақтығы жоғары [1].