Verification of Current Risk Scores for Kawasaki Disease in Korean Children

The purpose of this study was to evaluate and assess the compatibility of current risk scoring systems from Japan that were developed to predict intravenous immunoglobulin (IVIG) resistance in patients with Kawasaki disease (KD). The authors previously investigated another prediction model for patients with refractory KD in Korea. A retrospective study involving 350 patients with KD who were admitted between January 2014 and December 2015 was performed. Patients younger than 2 years were excluded for the propensity score matching in this study. Patients were classified into IVIG responders and IVIG resistance groups. The well-known Harada, Kobayashi, and Egami risk scores were calculated for each patient, and the proportion of high-risk patients was compared between the two groups for each risk score. Logistic regression analysis revealed that platelets, C-reactive protein (CRP) levels, and aspartate aminotransferase levels were independent predictors of IVIG resistance. Multivariate analysis suggested that platelets and CRP were risk factors. Risk-scoring systems from Japan have good specificity but low sensitivity. Among the three risk scoring systems, the Kobayashi risk score demonstrated significant differences between the IVIG resistance and IVIG responder groups in Korean patients with KD. It is very important to identify IVIG-resistant patients to protect them from ongoing coronary arterial lesion(s); therefore, early prediction and timely optimal additional treatment is of significant benefit. It would be helpful to construct a highly sensitive, exclusive scoring system for Korean patients with KD.ope

Ex Vivo Evaluation of Mechanical Anisotropic Tissues with High-Frequency Ultrasound Shear Wave Elastography

The use of imaging devices to assess directional mechanics of tissues is highly desirable. This is because the directional mechanics depend on fiber orientation, and altered directional mechanics are closely related to the pathological status of tissues. However, measuring directional mechanics in tissues with high-stiffness is challenging due to the difficulty of generating localized displacement in these tissues using acoustic radiation force, a general method for generating displacement in ultrasound-based elastography. In addition, common ultrasound probes do not provide rotational function, which makes the measurement of directional mechanics inaccurate and unreliable. Therefore, we developed a high-frequency ultrasound mechanical wave elastography system that can accommodate a wide range of tissue stiffness and is also equipped with a motorized rotation stage for precise imaging of directional mechanics. A mechanical shaker was applied to the elastography system to measure tissues with high-stiffness. Phantom and ex vivo experiments were performed. In the phantom experiments, the lateral and axial resolution of the system were determined to be 144 μm and 168 μm, respectively. In the ex vivo experiments, we used swine heart and cartilage, both of which are considered stiff. The elastography system allows us to acquire the directional mechanics with high angular resolution in the heart and cartilage. The results demonstrate that the developed elastography system is capable of imaging a wide range of tissues and has high angular resolution. Therefore, this system might be useful for the diagnostics of mechanically anisotropic tissues via ex vivo tests.ope

Left ventricular twist in children : Does LV rotation change with aging in children?

Dept. of Medicine/석사[한글] 본 연구는 소아의 연령 변화에 따른 좌심실 회전 및 심실 비틀림을 관찰한 연구이다. 현재까지 보고에 의하면 심실 비틀림은 나이에 따라 의미 있는 변화를 보이지는 않는다고 알려져 왔다. 그러나 어린이 연령에서 학동기 전 후 나이에 따른 좌심실 회전과 비틀림의 관계에 대해서는 알려진 바가 거의 없다.40명의 소아 중 학동기 전 어린이 20명 (2세 - 6세), 학동기 어린이 20명 (7세 - 12세)을 대상으로 하였고, 심초음파 단축 영상에서 심장 기저부와 심첨부를 각각 심근벽 구획에 따라 분리 분석하였다. 좌심실 회전 및 비틀림 양상은 심장 기저부와 심첨부에서 통계적 유의성은 없었으나 학동기 전 어린이 보다 학동기 어린이에서 감소하는 경향을 나타내었다. 즉 학동기 전 어린이에서 더 큰 심실 회전과 비틀림을 나타내는 경향을 보였다.소아의 심근증을 비롯한 기타 심장질환 평가 및 치료에 기여하고자 좌심실 회전 및 심실 비틀림 현상을 연령 변화에 따라 관찰하였으며, 향후 지속적인 연구가 필요할 것이다. [영문] Background The recently introduced method, speckle tracking echocardiography, represents simplified, objective, and angle-independent modality for quantification of regional myocardial deformation. As published, there was no significant change in LV torsion with aging, there might be some difference in LV rotation at base and apex. The purpose of this study was to assess the relationship of LV rotation for torsion with aging in children.Methods Forty healthy children were recruited and divided into two groups of twenty preschool age (2 ~ 6 years of age) and twenty school age children (7 ~ 12 years of age). After obtaining conventional echocardiographic data, apical and basal short axis rotations were assessed with speckle tracking echocardiography. LV rotations in basal and apical short axis planes were determined of six myocardial segments along the central axis.Results There was no significant change in apical and basal LV rotation with age between preschool and school age children. However, there was a certain trend between two age groups in each basal and apical rotation. In basal and apical rotation, the values of preschool age children are greater than those of school age children at anteroseptal, anterior, lateral, posterior, inferior, and septal all six segments.Conclusion There was some trend of incremental rotation value in preschool age children rather than school age children. Although there was no statistically significant age-related change in LV rotation between these two groups, the decrease trend with aging for rotation and torsion twist during childhood should be necessary for further investigation.ope

Myocardial Tissue Doppler Velocity in Child Growth

Background: In adults, tissue Doppler imaging (TDI) is a recommended component of routine echocardiography. However, TDI velocities are less accepted in pediatrics, due to their strong variability and age dependence in children. This study examines the distribution of myocardial tissue Doppler velocities in healthy children to assess the effect of age with cardiac growth on the various echocardiographic measurements. Methods: Total 144 healthy children were enrolled in this study. They were recruited from the pediatric outpatient clinic for routine well-child visits. The statistical relationships between age and TDI values were analyzed. Also, the statistical relationships between body surface area (BSA) and TDI values, left ventricle end-diastolic dimension (LVEDD) and TDI values were analyzed. Also, we conducted multivariate analysis of cardiac growth parameters such as, age, BSA, LVEDD and TDI velocity data. Results: All of the age, BSA, and LVEDD had positive correlations with deceleration time (DT), pressure half-time (PHT), peak early diastolic myocardial velocity, peak systolic myocardial velocity, and had negative correlations with peak late diastolic velocity (A) and the ratio of trans-mitral inflow velocity to early diastolic velocity of mitral annulus (E/E'). In the multivariate analysis, all of the age, BSA, and LVEDD had positive correlations with DT, PHT, and negative correlations with A and E/E'. Conclusion: The cardiac growth parameters related alterations of E/E' may suggest that diastolic myocardial velocities are cardiac growth dependent, and diastolic function has positive correlation with cardiac growth in pediatric group. This cardiac growth related myocardial functional variation would be important for assessment of cardiac involvement either in healthy and sick child.ope

A child with Kawasaki disease and genetic warfarin sensitivity from CYP2C9 and VKORC1 gene variants

Kawasaki disease (KD) is a common febrile disease in East Asia. Because KD with coronary artery aneurysm (CAA) may predispose to thrombosis, children with KD-associated CAA may need anticoagulation in addition to aspirin. In this report, we describe a 6-year-old girl with KD and CAA who was found to have unexpected warfarin-induced coagulopathy caused by CYP2C9 and VKORC1 genotype variants, which affect warfarin metabolism.ope

Explainable deep learning algorithm for distinguishing incomplete Kawasaki disease by coronary artery lesions on echocardiographic imaging

Background and objective: Incomplete Kawasaki disease (KD) has often been misdiagnosed due to a lack of the clinical manifestations of classic KD. However, it is associated with a markedly higher prevalence of coronary artery lesions. Identifying coronary artery lesions by echocardiography is important for the timely diagnosis of and favorable outcomes in KD. Moreover, similar to KD, coronavirus disease 2019, currently causing a worldwide pandemic, also manifests with fever; therefore, it is crucial at this moment that KD should be distinguished clearly among the febrile diseases in children. In this study, we aimed to validate a deep learning algorithm for classification of KD and other acute febrile diseases. Methods: We obtained coronary artery images by echocardiography of children (n = 138 for KD; n = 65 for pneumonia). We trained six deep learning networks (VGG19, Xception, ResNet50, ResNext50, SE-ResNet50, and SE-ResNext50) using the collected data. Results: SE-ResNext50 showed the best performance in terms of accuracy, specificity, and precision in the classification. SE-ResNext50 offered a precision of 81.12%, a sensitivity of 84.06%, and a specificity of 58.46%. Conclusions: The results of our study suggested that deep learning algorithms have similar performance to an experienced cardiologist in detecting coronary artery lesions to facilitate the diagnosis of KD.ope

Assessment of myocardial function in elite athlete's heart at rest - 2D speckle tracking echocardiography in Korean elite soccer players

The purpose of this study was to investigate Korean elite soccer players' myocardial function using the conventional and advanced speckle tracking imaging to compare the difference with the normal controls. We used 2D echocardiography speckle tracking echocardiography (STE) to evaluate LV regional strain in 29 elite soccer players compared to 29 age-matched healthy controls. Conventional, tissue Doppler, and STI echocardiography was performed, for strain at base and apex, rotation and torsion. There is no difference in longitudinal strain (-17.6?±?1.8 vs -17.3?±?2.9, p?=?ns), and basal radial strain. However, the significant increases were noticed in basal circumferential strain (-17.5?±?2.6 vs -15.5?±?8.9, p?=?0.05), apical radial strain (33.1?±?20.5 vs 22.5?±?19.4, p?=?0.02), and apical circumferential strain in soccer players (-21.4?±?4.8 vs -16.8?±?7.6, p?=?0.005). Soccer players showed the higher rotation at base (-3.9?±?1.9 vs -2.6?±?3.2, p?=?0.03), and apex (6.98?±?2.62 vs 6.21?±?3.81, p?=?0.05), higher torsion (10.9?±?3.7 vs 8.8?±?6.3, p?=?0.05). In conclusion, the elite soccer players' heart demonstrated the unique ventricular adaptation. These alterations could benefit the cardiovascular adjustment to exercise without much loss of myocardial energy expenditure.ope

Surveillance of COVID-19-Associated Multisystem Inflammatory Syndrome in Children, South Korea

A concerning development during the coronavirus disease pandemic has been multisystem inflammatory syndrome in children. Reports of this condition in East Asia have been limited. In South Korea, 3 cases were reported to the national surveillance system for multisystem inflammatory syndrome in children. All case-patients were hospitalized and survived with no major disease sequelae.ope

Left Ventricular Function after Mitral Valve Operation in Congenital Mitral Regurgitation

Background：Severe mitral regurgitation is a common clinical entity that can lead to progressive, irreversible left ventricular dysfunction, and thus should be corrected in proper stage of life. Authors have conducted this investigation to assess left ventricular function after mitral valve operation and to determine the predicting factors. Methods and Results：The echocardiographic parameters, specifically left ventricular ejection fraction, shortening fraction, end-systolic dimension and volume, and end-diastolic dimension and volume were measured in preoperative and postoperative period of congenital mitral regurgitation patients (n＝60), between March 1992 and March 1998. After correction of severe mitral regurgitaion, left ventricular ejection fraction and shortening fraction decreased significantly (p<0.001 and p<0.05 respectively). Furtheremore, after reoperation of recurred mitral regurgitation, left ventricular ejection fraction and shortening fraction decreased significantly (p<0.05). Left ventricular ejection fraction and shortening fraction in mitral valve reoperation group (n＝23) is significantly lower than those in non-reoperation group (n＝37) in both preoperative and postoperative period (p<0.05). Left ventricular ejection fraction and shortening fraction is also significantly lower in mitral valve replacement group (n＝20) than in mitral valvuloplasty group (n＝40)(p<0.05). Severe postoperative left ventricular dysfunction led to dilated cardiomyopathy in 5 patients. Postoperative left ventricular end systolic dimension increased significantly in reoperation group and DCMP group respectively (p<0.05). Conclusion：After surgical correction of mitral regurgitation, left ventricular dysfunction is frequent and carries a poor prognosis. Postoperative left ventricular dysfunction can be predicted by preoperative ejection fraction, shortening fraction and systolic diameter. Therefore surgical therapy before the onset of left ventricular dysfunction is recommended. (Korean Circulation J 2000;30(6):737-744)ope

Myocardial Layer-Specific Strain Analysis in Children with Mitochondrial Disease

PURPOSE: Children with mitochondrial disease (MD) have clinical phenotypes that are more severe than those found in adults. In this study, we assessed cardiac function in children with MD using conventional and advanced echocardiographic measurements, explored any unique patterns present, and investigated the development of early cardiomyopathy (CMP). MATERIALS AND METHODS: We retrospectively reviewed the medical records of 33 children with MD. All patients underwent transthoracic echocardiography with conventional and advanced myocardial analysis. We compared all data between patients and an age-matched healthy control group. RESULTS: Conventional echocardiographic diastolic measurements of mitral E, E/A, and tissue Doppler E' were significantly lower and E/E' was significantly higher in children with MD, compared with the measurements from the control group. There was no significant difference in longitudinal and radial strain between the groups. Circumferential strain in the endocardium (p=0.161), middle myocardium (p=0.008), and epicardium (p=0.042) were lower in patients, compared to the values in controls. Circumferential strain was correlated with E' (p0.60). CONCLUSION: In children with MD, myocardial circumferential strain may develop early in all three layers, even with normally preserved longitudinal and radial strain. This may be an early diagnostic indicator with which to predict CMP in this patient population.ope