• Korean Journal of Radiology
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• v.22 no.11
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• pp.1764-1776
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• 2021

Objective: This study aimed to validate a deep learning-based fully automatic calcium scoring (coronary artery calcium [CAC]_auto) system using previously published cardiac computed tomography (CT) cohort data with the manually segmented coronary calcium scoring (CAC_hand) system as the reference standard. Materials and Methods: We developed the CAC_auto system using 100 co-registered, non-enhanced and contrast-enhanced CT scans. For the validation of the CAC_auto system, three previously published CT cohorts (n = 2985) were chosen to represent different clinical scenarios (i.e., 2647 asymptomatic, 220 symptomatic, 118 valve disease) and four CT models. The performance of the CAC_auto system in detecting coronary calcium was determined. The reliability of the system in measuring the Agatston score as compared with CAC_hand was also evaluated per vessel and per patient using intraclass correlation coefficients (ICCs) and Bland-Altman analysis. The agreement between CAC_auto and CAC_hand based on the cardiovascular risk stratification categories (Agatston score: 0, 1-10, 11-100, 101-400, > 400) was evaluated. Results: In 2985 patients, 6218 coronary calcium lesions were identified using CAC_hand. The per-lesion sensitivity and false-positive rate of the CAC_auto system in detecting coronary calcium were 93.3% (5800 of 6218) and 0.11 false-positive lesions per patient, respectively. The CAC_auto system, in measuring the Agatston score, yielded ICCs of 0.99 for all the vessels (left main 0.91, left anterior descending 0.99, left circumflex 0.96, right coronary 0.99). The limits of agreement between CAC_auto and CAC_hand were 1.6 ± 52.2. The linearly weighted kappa value for the Agatston score categorization was 0.94. The main causes of false-positive results were image noise (29.1%, 97/333 lesions), aortic wall calcification (25.5%, 85/333 lesions), and pericardial calcification (24.3%, 81/333 lesions). Conclusion: The atlas-based CAC_auto empowered by deep learning provided accurate calcium score measurement as compared with manual method and risk category classification, which could potentially streamline CAC imaging workflows.

• Korean Circulation Journal
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• v.54 no.6
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• pp.339-350
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• 2024

Background and Objectives: Ultimaster^TM, a third-generation sirolimus-eluting stent using biodegradable polymer, has been introduced to overcome long term adverse vascular events, such as restenosis or stent thrombosis. In the present study, we aimed to evaluate the 12-month clinical outcomes of Ultimaster^TM stents in Korean patients with coronary artery disease. Methods: This study is a multicenter, prospective, observational registry across 12 hospitals. To reflect real-world clinical evidence, non-selective subtypes of patients and lesions were included in this study. The study end point was target lesion failure (TLF) (the composite of cardiac death, target vessel myocardial infarction [MI], and target lesion revascularization [TLR]) at 12-month clinical follow up. Results: A total of 576 patients were enrolled between November 2016 and May 2021. Most of the patients were male (76.5%), with a mean age of 66.0±11.2 years. Among the included patients, 40.1% had diabetes mellitus (DM) and 67.9% had acute coronary syndrome (ACS). At 12 months, the incidence of TLF was 4.1%. The incidence of cardiac death was 1.5%, MI was 1.0%, TLR was 2.7%, and stent thrombosis was 0.6%. In subgroup analysis based on the presence of ACS, DM, hypertension, dyslipidemia, or bifurcation, there were no major differences in the incidence of the primary endpoint. Conclusions: The present registry shows that Ultimaster^TM stent is safe and effective for routine real-world clinical practice in non-selective Korean patients, having a low rate of adverse events at least up to 12 months.

• Clinical and Experimental Pediatrics
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• v.46 no.8
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• pp.811-816
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• 2003

Purpose : Kawasaki disease is an acute systemic vasculitis of unknown etiology with a predilection for the coronary arteries. Vascular endothelial growth factor(VEGF) is a cytokine which promotes vascular permeability and angiogenesis. We investigated serum VEGF(sVEGF) levels in Kawasaki disease to determine whether sVEGF level can be used as a risk factor to predict the occurrence of coronary artery lesions(CAL) in Kawasaki disease. Methods : We measured sVEGF levels in 11 patients with Kawasaki disease in acute phase(patient group)and 11 normal children(control group) by enzyme-linked immunosorbent assay(ELISA) method. We investigated the relationship between sVEGF levels and the lumen diameters of coronary artery and other potential CAL risk factors; duration of fever, hemoglobin, WBC counts, platelet counts, ESR, CRP and LDH levels. Results : SVEGF levels of patients in the acute phase of Kawasaki disease(mean $847.9{\pm}495.7pg/mL$) were significantly higher than that of normal controls(mean $279.9{\pm}150.6pg/mL$; P<0.05). SVEGF levels showed significant positive correlation with the lumen diameters of the coronary artery(P<0.05, $r_s=0.75$) in the patient group. There was no significant correlation between sVEGF levels and duration of fever or other laboratory measurements. Conclusion : Our results support the notion that sVEGF level may be considered as a predictive indicator for the occurrence of coronary artery lesions in Kawasaki disease.

• Journal of Chest Surgery
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• v.16 no.3
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• pp.349-355
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• 1983

Twenty-seven patients with double-outlet right ventricle underwent complete intracardiac repair between 1978 and 1983, June, at Seoul National University Hospital . Although definite aorto-mitral discontinuity was discovered in 20 patients, both great arteries arose wholly or mostly from the right ventricle in all cases. There were 17 cases with subaortic VSD, 6 with subpulmonic, 2 with doubly-committed, and 2 with non-committed VSD. Pulmonary stenosis was present in 21 patients. Intraventricular baffle repair was applied in 23 patients. Three patients required extracardiac conduit to establish continuity between right ventricle and pulmonary artery, and modified Fontan operation was performed in one patient. Over-all mortality rate was 37.0%, but recently 4 of 15 died [26.7%]. One late death occurred from infective endocarditis. Incremental risk factors were small patient size, subpulmonic or non-committed VSD, presence of PS, coronary artery anomalies, associated valvular lesion and other complicated anomalies. However, great artery relationship, restrictive VSD and transannular patch were not risk factors. No instances of complete heart block occurred. Of the survivors, all showed complete or in complete right bundle branch block and in one patient intermittent ventricular tachycardia had developed. The important cause of death was low cardiac output syndrome.

• Journal of Chest Surgery
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• v.31 no.2
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• pp.118-124
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• 1998

Minimally invasive coronary artery bypass grafting without using cardiopulmonary bypass (CPB) is a recently accepted modality of myocardial revascularization prcedures which is particularly suitable to the patients with lesions in the left anterior descending(LAD) and the right coronary arteries. Of the consecutive 35 patients of coronary artery bypass grafting performed at Sejong General Hospital from March to August 1996, six patients underwent minimally invasive coronary artery bypass grafting without CPB. All had stenotic lesions of the LAD more than 90%. Bypass grafting of the LAD was approached through midline sternotomy in one, through ministernotomy in two, and through limited left anterior thoracotomy in three patients, respectively. The internal mammary arteries were prepared without the use of thoracoscope. The mobilized mammary arteries were connected directly to the LAD in 5 patients, and the anastomosis required interposition of a segment of the radial artery in the remaining one. The diagonal branch was revascularized with the saphenous vein graft at the same time in one patient. No blood transfusion was necessary in 2 patients, and average blood required during surgery was 800ml in 4 patients. All patients were extubated from 4 to 14 hours(mean 9 hours) after operation. Early postoperative coronary angiography in 5 patients between 7 and 10 days after surgery has proved full patency of the grafts. With these limited clinical experiences, the clinical results demonstrated that minimally invasive coronary artery bypass grafting without CPB is an useful procedure especially in patients with isolated lesion in the proximal LAD.

• Clinical and Experimental Pediatrics
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• v.49 no.10
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• pp.1093-1099
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• 2006

Purpose : Homocysteine is a strong and independent risk factor for cardiovascular disease. The deleterious effects of homocysteine included endothelial dysfunction, arterial intimal-medial thickening, wall stiffness and procoagulant activity. However, the precise mechanism responsible for homocysteine release in children with coronary artery disease is still unknown. The purpose of this study was to investigate serum homocysteine and tumor necrosis $factor(TNF)-{\alpha}$ levels and identify whether these levels had any association with the development of coronary artery lesions in Kawasaki disease(KD). Methods : Serum homocysteine and $TNF-{\alpha}$ levels were measured in 24 KD patients(group 1, eight patients with normal coronary artery; group 2, 16 patients with coronary artery lesions) and 21 controls(group 3, 10 afebrile controls; group 4, 11 febrile controls). Blood samples were drawn from each study group before and after intravenous immunoglobulin(IVIG) therapy and in the convalescent stage. Results : The homocysteine levels before IVIG therapy were significantly higher in group 1 than in group 3, and in group 2 than in group 3 and 4. The $TNF-{\alpha}$ levels before IVIG therapy were significantly higher in group 2 than group 3 and 4. Serum homocysteine and $TNF-{\alpha}$ levels were highest in group 2 before IVIG therapy. In the acute KD patients, serum homocysteine levels correlated significantly with $TNF-{\alpha}$ levels. Conclusion : The increased serum homocysteine levels in the acute stage increase the susceptibility to coronary arterial lesions in KD. $TNF-{\alpha}$ may also play an important role in the formation of coronary arterial lesions in KD.

• Childhood Kidney Diseases
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• v.12 no.1
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• pp.105-110
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• 2008

Renovascular hypertension results from a lesion that impairs blood flow to a part of or all, of one or both kidneys. Renal artery stenosis is the major cause of renovascular hypertension and the most common cause of treatable secondary hypertension. Recently, percutaneous transluminal renal angioplasty(PTRA) with or without stent placement, has become the preferred choice for correcting symptomatic renal artery stenosis since it is less invasive than surgical reconstruction. PTRA with balloons designed for the dilatation for the dilatation of the coronary artery can be tried in small sized renal artery stenosis. We report a case of renovascular hypertension in a 13-year-old male who had small sized renal artery stenosis. Hypertension was controlled by PTRA with balloon dilatation.

• Journal of the Korean Society of Radiology
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• v.82 no.6
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• pp.1493-1504
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• 2021

Purpose This study aimed to evaluate the utility of the 16-cm axial volume scan technique for calculating the coronary artery calcium score (CACS) using non-enhanced chest CT. Materials and Methods This study prospectively enrolled 20 participants who underwent both, non-enhanced chest CT (16-cm-coverage axial volume scan technique) and calcium-score CT, with the same parameters, differing only in slice thickness (in non-enhanced chest CT = 0.625, 1.25, 2.5 mm; in calcium score CT = 2.5 mm). The CACS was calculated using the conventional Agatston method. The difference between the CACS obtained from the two CT scans was compared, and the degree of agreement for the clinical significance of the CACS was confirmed through sectional analysis. Each calcified lesion was classified by location and size, and a one-to-one comparison of non-contrast-enhanced chest CT and calcium score CT was performed. Results The correlation coefficients of the CACS obtained from the two CT scans for slice thickness of 2.5, 1.25, and 0.625 mm were 0.9850, 0.9688, and 0.9834, respectively. The mean differences between the CACS were -21.4% at 0.625 mm, -39.4% at 1.25 mm, and -76.2% at 2.5 mm slice thicknesses. Sectional analysis revealed that 16 (80%), 16 (80%), and 13 (65%) patients showed agreement for the degree of coronary artery disease at each slice interval, respectively. Inter-reader agreement was high for each slice interval. The 0.625 mm CT showed the highest sensitivity for detecting calcified lesions. Conclusion The values in the non-contrast-enhanced chest CT, using the 16-cm axial volume scan technique, were similar to those obtained using the CACS in the calcium score CT, at 0.625 mm slice thickness without electrocardiogram gating. This can ultimately help predict cardiovascular risk without additional radiation exposure.

• Journal of Yeungnam Medical Science
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• v.11 no.2
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• pp.230-239
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• 1994

In Order to evaluate determinants of successful percutaneous transluminal coronary angioplasty (PTCA), PTCA was performed for 172 coronary arterial lesions in 120 patients (89 male, 31 female) at Yeungnam university hospital from Sep. 1992 to Aug. 1993. The corinary artery luminal diameter at the site of the original stenosis was eveluated from end-diastolic frames of identical projections of the preangioplasty and immediate post angioplasty. The coronary luminal and balloon diameters were measured with using of computer measuring system. Overall success rate of 172 attempted lesions was 87.2%. Success rate of female patients was 93.5% and higher than those of male patients. According to the clinical diagnosis, success rate in stable angina was 93.7% and higher than those of post myocardial infarction angina, unstable angina and acute myocardial infarcrion. Success rate of American Heart Association type C lesion was 65.5% and lower those of type A (95.7%), type B (89.5%). There was signfifcantly difference in preangioplasty luminal stenosis, elastic recoil and length of lesion between successful PTCA group and failed PTCA group. Success rate of lesion location at a bend > $45^{\circ}$ and presence of intracoronary thrombus were lower than than those of other angiographic findings. In coclusion, primary angioplasty success was affected by specific angiographic factors. Stenosis severity, thrombus, lesion location at a bend > $45^{\circ}$, elastic recoil, and length of lesion were the principle of determinants of coronary angioplasty success rate.

• Journal of radiological science and technology
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• v.33 no.1
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• pp.37-44
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• 2010

We sought to confirm an independent factor about in-stent restenosis (ISR) in the patients who underwent drug-eluting stent (DES) and know a possibility as a predictor of measured coronary artery calcium score by MDCT. A total of 178 patients (159 men, $61.7{\pm}10.0$ years of age) with 190 coronary artery lesions were included in this study out of 1,131 patients who underwent percutaneous coronary intervention (PCI) with DES implantation for significant stenosis on MDCT at Chonnam National University Hospital between May 2006 and May 2009. All lesions were divided into two groups with the presence of ISR : group I (re ISR, N = 57) and group II (no ISR, N = 133). Compared to group II, group I was more likely to be older ($65.8{\pm}9.0$ vs. $60.2{\pm}9.9$ years, p = 0.0001), diabetic (21.8% vs. 52.6%, p = 0.0001), have old myocardial infarction (8.8% vs. 2.3%, p = 0.040), left main stem disease (5.3% vs. 0.8%, p = 0.047), and smaller stent size ($3.1{\pm}0.3\;mm$ vs. $3.3{\pm}0.4\;mm$, p = 0.004). Group II was more likely to be smokers (19.3% vs. 42.1%, p = 0.003), have dyslipidemia (8.8% vs. 23.3%, p = 0.019). Left ventricular ejection fraction, lesion complexity, and stent length were not different between the two groups. Total CAC score was $389.3{\pm}458.3$ in group I and $371.2{\pm}500.8$ in group II (p = 0.185). No statistical difference was observed between the groups in CAC score in the culprit vessel, left main stem, left anterior descending artery, left circumflex artery, and right coronary artery. On multivariate logistic regression analysis, left main stem disease (OR = 168.0, 95% CI = 7.83-3,604.3, p = 0.001), male sex (OR = 36.5, 95% CI = 5.89-2,226.9, p = 0.0001), and the presence of diabetes (OR = 2.62, 95% CI = 1.071-6.450, p = 0.035) were independent predictors of ISR after DES implantation. In patients who underwent DES implantation for significant coronary stenosis on MDCT, ISR was associated with left main stem disease, male sex, and the presence of diabetes. However, CAC score by MDCT was not a predictor of ISR in this study population.