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Abstract Background Atrial functional mitral regurgitation (AFMR) is a newly discovered condition associated with longstanding atrial fibrillation. This retrospective study aimed to analyze the outcomes of the maze procedure and mitral regurgitation (MR) surgery in AFMR and atrial fibrillation in comparison with those in degenerative MR (DMR). Methods Patients who underwent mitral valve repair/replacement with a maze procedure at a hospital (July 2012–August 2021) were included. We excluded patients aged below 18 years undergoing concomitant coronary artery bypass grafting or atrial septal defect repair and those with MR etiology other than ARMR or DMR. Results We included 35 patients with AFMR and 50 patients with DMR. Patient characteristics and postoperative outcomes were not significantly different between the two groups. Long-term outcomes revealed no significant differences in the ratio of cardiac mortality, stroke, or hospital readmission. However, after the maze procedure, the sinus rhythm restoration rate was significantly lower (62% vs. 28.5%, p

Background: Pump-controlled retrograde trial off (PCRTO) is a safe, simple, and reversible method for weaning patients from veno-arterial extracorporeal membrane oxygenation (VA-ECMO). However, few studies have compared PCRTO to conventional weaning methods. This retrospective study aimed to compare PCRTO to non-PCRTO methods. Methods: This study included patients who were weaned from VA-ECMO from January 2016 to December 2022 at our medical center. Demographic data, ECMO management, ECMO complications, survival to discharge, and cardiogenic shock after VA-ECMO weaning were compared between the 2 groups. Results: Seventy patients who were weaned from VA-ECMO using PCRTO and 85 patients who were weaned with conventional methods were compared. Patient characteristics were not significantly different between the 2 groups. The rate of survival to discharge was significantly higher in the PCRTO group than in the non-PCRTO group (90% vs. 72%, p=0.01). The rates of freedom from all-cause mortality at 10, 30, and 50 days after weaning from ECMO were 75%, 55%, and 35% in the non-PCRTO group and 62%, 60%, and 58% in the PCRTO group, respectively (p=0.1). The incidence of cardiogenic shock after weaning from VA-ECMO was significantly higher in the non-PCRTO group (16% vs. 5%, p=0.04). In logistic regression analysis, PCRTO was a significant factor for survival to discharge (odds ratio, 2.42; 95% confidence interval, 1.29–5.28; p=0.02). Conclusion: Compared to conventional methods, PCRTO is a feasible and reversible method, and it serves as a useful predictor of successful VA-ECMO weaning through a preload stress test.

Background: Superior vena cava (SVC) stenosis during follow-up is a major concern after heart transplantation, and many technical modifications have been introduced. We analyzed the surgical results of the SVC intima layer-only suture technique in heart transplantation. Methods: We performed SVC anastomosis with sutures placed only in the intima during heart transplantation. We measured the area of the SVC at 3 different points (above the anastomosis, at the anastomosis, and below the anastomosis) in an axial view by freely drawing regions of interest, and then evaluated the degree of stenosis. Patients who underwent cardiac computed tomography (CT) at 2 years postoperatively between June 2017 and May 2020 were included in this study. Results: We performed heart transplantation in 41 patients. Among them, 24 patients (16 males and 8 females) underwent follow-up cardiac CT at 2 years postoperatively. The mean age at operation was 49.4±4.9 years. The diagnoses at time of operation were dilated cardiomyopathy (n=12), ischemic heart disease (n=8), valvular heart disease (n=2), hypertrophic cardiomyopathy (n=1), and congenital heart disease (n=1). No cases of postoperative bleeding requiring intervention occurred. The mean CT follow-up duration was 1.9±0.7 years. At follow-up, the mean areas at the 3 key points were 2.7±0.8 cm2, 2.7±0.8 cm2, and 2.7±1.0 cm2 (p=0.996). There were no SVC stenosis-related symptoms during follow-up. Conclusion: The suture technique using only the SVC intimal layer is a safe and effective method for use in heart transplantation.

Background Additional retrograde cardioplegia infusion in conventional coronary artery bypass grafting (CABG) was introduced to address the concern of inappropriate cardioplegia delivery through the stenotic coronary artery. However, this method is complex and requires repeated infusions. Therefore, we investigated the surgical outcomes of only antegrade cardioplegia infusion in conventional CABG. Methods We included 224 patients who underwent isolated CABG between 2017 and 2019. The patients were divided into two groups according to the cardioplegia infusion method: antegrade cardioplegia infusion with del Nido solution (n=111, group I) and antegrade+retrograde cardioplegia infusion with blood cardioplegia solution (n=113, group II). Results The sinus recovery time after release of the aorta cross-clamp was shorter in group I (3.8±7.1 minutes, n=98) than in group II (5.8±4.1 minutes, n=73) (p=0.033). The total cardioplegia infusion volume was lower in group I (1,998.6±668.6 mL) than in group II (7,321.0±2,865.3 mL) (p

Abstract Background The diagnosis of dental implants and the periapical tissues using periapical radiographs is crucial. Recently, artificial intelligence has shown a rapid advancement in the field of radiographic imaging. Purpose This study attempted to detect dental implants and peri-implant tissues by using a deep learning method known as object detection on the implant image of periapical radiographs. Methods After implant treatment, the periapical images were collected and data were processed by labeling the dental implant and peri-implant tissue together in the images. Next, 300 images of the periapical radiographs were split into 80:20 ratio (i.e. 80% of the data were used for training the model while 20% were used for testing the model). These were evaluated using an object detection model known as Faster R-CNN, which simultaneously performs classification and localization. This model was evaluated on the classification performance using metrics, including precision, recall, and F1 score. Additionally, in order to assess the localization performance, an evaluation through intersection over union (IoU) was utilized, and, Average Precision (AP) was used to assess both the classification and localization performance. Results Considering the classification performance, precision = 0.977, recall = 0.992, and F1 score = 0.984 were derived. The indicator of localization was derived as mean IoU = 0.907. On the other hand, considering the indicators of both classification and localization performance, AP showed an object detection level of AP@0.5 = 0.996 and AP@0.75 = 0.967. Conclusion Thus, the implementation of Faster R-CNN model for object detection on 300 periapical radiographic images including dental implants, resulted in high-quality object detection for dental implants and peri-implant tissues.

Abstract Background Total anomalous pulmonary venous return (TAPVR) is rare congenital heart disease. Most TAPVRs require surgical corrections in the neonatal period and survival to adulthood without surgical correction is extremely rare. Most untreated patients with large atrial septal defects and no pulmonary venous obstruction have pulmonary vascular damage from pulmonary over circulation. Case presentation 44-year-old TAPVR patient admitted to our medical center. A snowman-shaped heart, including cardiomegaly and an increase in pulmonary blood flow, was seen in the chest X-ray. A large-sized (around 3 cm) atrial septal defect with dilated right atrium, right ventricle, and pulmonary artery was detected on echocardiography. Heart computed tomography was performed for further evaluation, and supra-cardiac type TAPVR without any obstructive lesion was identified. Conclusions TAPVR in an adult patient is extremely rare, and this patient was treated successfully with surgical correction and is doing well. A sinus rhythm and mild mitral valve regurgitation have remained during 2.5 years of outpatient follow-up.

Abstract The muscular discontinuities at the pulmonary vein (PV)–left atrial (LA) junction are known. The high-density mapping may help to find the muscular discontinuity. This study evaluated the efficacy of a partial antral ablation for a pulmonary vein (PV) isolation using high density (HD) mapping. A total of 60 drug-refractory atrial fibrillation (AF) patients undergoing catheter ablation were enrolled. The detailed activation mapping of each PV and LA junction was performed using an HD mapping system, and each PV segment’s activation pattern was classified into a “directly-activated from the LA” or “passively-activated from an adjacent PV segment” pattern. The antral ablations were performed at the directly-activated PV segments only when the PV had “passively-activated segments”. If the PV did not contain passively-activated segments, a circumferential antral ablation was performed on those PVs. A “successful partial antral ablation” was designated if the electrical isolation of targeted PV was achieved by ablation at the directly-activated segments only. If the isolation was not achieved even though all directly-activated segments were ablated, a “failed partial antral ablation” was designated, and then a circumferential ablation was performed. Among 240 PVs, passively-activated segments were observed in 140 (58.3%) PVs. Both inferior PVs had more passively-activated segments than superior PVs, and the posteroinferior segments had the highest proportion of passive activation. The overall rate of successful partial antral ablation was 85%. The atrial tachyarrhythmia recurrence was observed in 10 patients (16.7%) at 1-year. HD mapping allowed the evaluation of the detailed activation patterns of the PVs, and passively-activated segments may represent muscular discontinuity. Partial antral ablation of directly-activated antral segments only was feasible and effective for a PVI.

The anomalous connection of umbilical vessels to the heart is rare and has not yet been reported in the international scientific literature. Herein, we report the case of a newborn who was diagnosed with an anomalous connection of the umbilical vessels to the left ventricle. These anomalous vessels were functionally open for 2 weeks, and cellulitis was present in the area of the blood vessels connected to the skin. We performed division of these abnormal vessels and removal of the skin lesion.

Since the first reported case of coronavirus disease 2019 (COVID-19) in December 2019, the numbers of confirmed cases and deaths have continued to increase exponentially despite multi-factorial efforts. Although various attempts have been made to improve the level of evidence for extracorporeal membrane oxygenation (ECMO) treatment over the past 10 years, most experts still hesitate to take an active position on whether to apply ECMO in COVID-19 patients. Several ECMO management guidelines have been published recently, but they reflect some important differences from the Korean medical system and aspects of real-world medical practice in Korea. We aimed to find evidence on the efficacy of ECMO for COVID-19 patients by reviewing the published literature and to propose expert recommendations by analyzing the Korean COVID-19 ECMO registry data.

Background: Atrial septal defect (ASD) is the most common congenital heart disease. However, the details of cardiac chamber remodeling after surgery are not well known, although this is an important issue that should be analyzed to understand long-term outcomes. Methods: Between November 2017 and January 2019, cardiac magnetic resonance imaging was performed preoperatively, at a 1-month postoperative follow-up, and at a 1-year postoperative follow-up. Cardiac chamber volume, valve regurgitation volume, and ejection fraction were measured as functions of time. Results: Thirteen patients (10 men and 3 women) were included. The median age at surgery was 51.4 years. The preoperative median ratio of flow in the pulmonary and systemic circulation was 2.3. The preoperative mean right ventricular (RV) end-diastolic volume index (EDVi) and RV end-systolic volume index (ESVi) had significantly decreased at the 1-month postoperative follow-up (p

In requirement engineering, it is a very important issue to generate test cases with natural language automatically. However, no test case tools deal with informal Korean requirement specifications. In the Korean military software system and airspace industrial area, it is strongly suggested to automatically make just 30% of all possible test cases with requirements. Unlike the previous approaches, we adapted Gary E. Mogyorodi’s cause-effect graphing approach and the model-driven architecture (MDA) approach for automatic test case generation with natural language. In order to generate test cases with informal Korean requirement specifications, we propose an automatic cause–effect tool as an intermediate model for (1) simplifying complicated requirements; (2) modeling the C3Tree (that is, condition and result); (3) identifying incomplete requirements; (4) constructing causes, effects, and relationships; and (5) integrating with two units (that is, similar causes or effects) to remove redundant requirements. We evaluated the accuracy of two generated cause–effect graphs in two ways. With our approach, we can also remove requirement redundancy.

Metabolic abnormalities, such as preexisting diabetes or hyperglycemia or hypoglycemia during hospitalization aggravated the severity of COVID-19. We evaluated whether diabetes history, hyperglycemia before and during extracorporeal membrane oxygenation (ECMO) support, and hypoglycemia were risk factors for mortality in patients with COVID-19. This study included data on 195 patients with COVID-19, who were aged ≥19 years and were treated with ECMO. The proportion of patients with diabetes history among nonsurvivors was higher than that among survivors. Univariate Cox regression analysis showed that in-hospital mortality after ECMO support was associated with diabetes history, renal replacement therapy (RRT), and body mass index (BMI) < 18.5 kg/m2. Glucose at admission >200 mg/dL and glucose levels before ventilator >200 mg/dL were not associated with in-hospital mortality. However, glucose levels before ECMO >200 mg/dL and minimal glucose levels during hospitalization 200 mg/dL before ECMO and minimal glucose 200 mg/dL before ECMO and minimal glucose level

Left main bronchus compression occasionally occurs in patients with cardiac disease. A 19-month-old female patient weighing 6 .7 k g was admitted for recurrent pneumonia a nd d esaturation. S he h ad a n atrial s eptal defect ( AS D) w ith a right aortic a rch. Her l eft main b ronchus h ad b een compressed b etween t he e nlarged right pulmonary artery (RPA) and the descending thoracic aorta for 14 months. We conducted ASD closure and RPA anterior translocation via sternotomy. The left main bronchus compression was relieved despite the medium- term duration of compression.

A male patient weighing 2.5 kg was admitted for respiratory difficulty, and a large ventricular septal defect (VSD) was diagnosed. During care, sudden right leg swelling with a femur shaft fracture occurred. The patient’s father had a history of recurrent lower extremity fractures; thus, osteogenesis imperfecta was considered. The patient’s respiratory difficulty became aggravated, and VSD repair in the neonatal period was therefore performed with gentle sternal traction and great vessel manipulation under total intravenous anesthesia to prevent malignant hyperthermia. The patient was discharged without notable problems, except minor wound dehiscence. Outpatient genetic testing revealed that the patient had a COL1A1/COL1A2 mutation.

In requirement engineering, an important issue is how to transform and tailor the informal system requirements of users or customers into more structured specification documents, which are then used by the software developers. In addition, it is both challenging and necessary to redefine and analyze, from ill-defined or unknown requirements, specifications correctly and automatically generate test cases with them. There are few kinds of research in Korea for automatically reducing requirement complexity and developing test cases of the Korean language-based requirement specifications. Why do we need requirement simplification? Requirement complexity causes analyzers less readability and low understandability. To do this, we propose the automatic cause-effect generation via a requirement simplification mechanism of informal requirement specifications with the Korean language, which works the following procedures: (1) the automatic simplification of informal requirement sentences, (2) the generation of Condition/Conjunction/Clause Tree (C3Tree) Model, (3) and the Cause-effect generation.

Background: Recent developments in surgical techniques and hospital care have led to improved outcomes following total anomalous pulmonary venous return (TAPVR) repair. However, the surgical repair of TAPVR remains associated with a high risk of mortality and need for reoperation. We conducted this retrospective study to evaluate mid-term outcomes following in situ TAPVR repair without total circulatory arrest (TCA), and to identify the risk factors associated with surgical outcomes. Methods: We retrospectively reviewed 29 cases of surgical intervention for TAPVR conducted between April 2000 and July 2015. All patients were newborns or infants who underwent in situ TAPVR repair without TCA. Results: Four anatomic subtypes of TAPVR were included in this study: supracardiac (20 cases, 69.0%), cardiac (4 cases, 13.8%), infracardiac (4 cases, 13.8%), and mixed (1 case, 3.4%). The median follow-up period for all patients was 42.9 months. Two (6.9%) early mortalities occurred, as well as 2 (6.9%) cases of postoperative pulmonary venous obstruction (PVO). Preoperative ventilator care (p=0.027) and preoperative PVO (p=0.002) were found to be independent risk factors for mortality. Conclusion: In situ repair of TAPVR without TCA was associated with encouraging mid-term outcomes. Preoperative ventilator care and preoperative PVO were found to be independent risk factors for mortality associated with TAPVR repair.

Background: Monocusp reconstruction with a transannular patch (TAP) results in early improvement because it relieves residual volume hypertension during the immediate postoperative period. However, few reports have assessed the long-term surgical outcomes of this procedure. The purpose of the present study was to evaluate the mid-term surgical outcomes of tetralogy of Fallot (TOF) repair using monocusp reconstruction with a TAP. Methods: Between March 2000 and March 2009, 36 patients with a TOF received a TAP. A TAP with monocusp reconstruction (group I) was used in 25 patients and a TAP without monocusp reconstruction (group II) was used in 11 patients. We evaluated hemodynamic parameters using echocardiography during t he f ollow-up p eriod in b oth groups. Results: At the most recent follow-up echocardiography (mean follow-up, 8.2 years), the mean pulmonary valve velocities of the patients in group I and group II were 2.1±1.0 m/sec and 0.9±0.9 m/sec, respectively (p=0.001). Although the incidence of grade 3–4 pulmonary regurgitation (PR) was not significantly different between the two groups (group I: 16 patients, 64.0%; group II: 7 patients, 70.0%; p=0.735) during the follow-up period, the interval between the treatment and the incidence of PR aggravation was longer in group I than in group II (group I: 6.5±3.4 years; group II: 3.8±2.2 years; p=0.037). Conclusion: Monocusp reconstruction with a TAP prolonged the interval between the initial treatment and grade 3–4 PR aggravation. Patients who received a TAP with monocusp reconstruction to repair T OF w ere not to p rogress to p ulmonary s tenosis during t he f ollow-up p eriod as t hose who received a TAP without monocusp reconstruction.

Williams syndrome (WS) is a developmental disorder characterized by vascular abnormalities such as thickening of the vascular media layer in medium- and large-sized arteries. Supravalvular aortic stenosis (SVAS) and peripheral pulmonary artery stenosis (PPAS) are common vascular abnormalities in WS. The natural course of SVAS and PPAS is variable, and the timing of surgery or intervention is determined according to the progression of vascular stenosis. In our patient, SVAS and PPAS showed rapid concurrent progression within two weeks after birth. We report the early manifestation of SVAS and PPAS in the neonatal period and describe the surgical treatment for stenosis relief.

HS Solar Energy Company Inc. in Sejong city, Korea, has a big problem on how to monitor heterogeneous inverters with different protocols. Still a current photovoltaic power plant with different inverters, it has attracted significant attention to its experience of difficulties in monitoring integrated power generation. To solve this problem for the company, we adapt a metamodel mechanism to easily manage and integrate heterogeneous data into a metamodel-based data format. The existing metamodel-based photovoltaic monitoring system (M-PVMS) of the HS solar energy company also needs to simply predict the photovoltaic power generation in a day for small farm owners in the countryside. Therefore, we propose a method for predicting the power generation of M-PVMS panels using the gated recurrent unit (GRU) algorithm, which supports real-time learning to predict the photovoltaic system behavior that rapidly accumulates data in real time. As a result, we can predict the power generation for small farm owners with a probability of 96.353%.

Background: Mitral regurgitation is one of the leading causes of cardiovascular morbidity in pediatric patients with Marfan syndrome. The purpose of this study was to contribute to determining the appropriate surgical strategy for these patients. Methods: From January 1992 to May 2013, six patients with Marfan syndrome underwent surgery for mitral regurgitation in infancy or early childhood. Results: The median age at the time of surgery was 47 months (range, 3 to 140 months) and the median follow-up period was 3.6 years (range, 1.3 to 15.5 years). Mitral valve repair was performed in two patients and four patients underwent mitral valve replacement with a mechanical prosthesis. There was one reoperation requiring valve replacement for aggravated mitral regurgitation two months after repair. The four patients who underwent mitral valve replacement did not experience any complications related to the prosthetic valve. One late death occurred due to progressive emphysema and tricuspid regurgitation. Conclusion: Although repair can be an option for some patients, it may not be durable in infantile-onset Marfan syndrome patients who require surgical management during infancy or childhood. Mitral valve replacement is a feasible treatment option for these patients.

The half-turned truncal switch (HTTS) operation has been reported as an alternative to the Rastelli or réparation à l’étage ventriculaire procedures. HTTS prevents left ventricular outflow tract (LVOT) obstruction in patients with complete transposition of the great arteries (TGA) with a ventricular septal defect (VSD) and pulmonary stenosis (PS), or in those with a Taussig-Bing anomaly with PS. The advantages of the HTTS procedure are avoidance of late LVOT or right ventricular outflow tract (RVOT) obstruction, and of overstretching of the pulmonary artery. We report the case of a patient who underwent HTTS for TGA with VSD and PS, in whom there was no LVOT obstruction and only mild aortic regurgitation and mild RVOT obstruction, including observations at 12-year follow-up. Our experience with long-term follow-up of HTTS supports a solution for late complications after the Rastelli procedure.

Although cardiac myxoma is the most commonly encountered benign cardiac tumor in cardiac surgery practice, recurrent cardiac myxoma is very rare, is most commonly related to the Carney complex, and usually requires multiple cardiac operations with specific requirements in terms of perioperative management. In this report, we describe a patient who experienced the fourth recurrence of cardiac myxoma and review the diagnostic criteria of the Carney complex. This is the first report of such a case in Korea.