• Journal of Chest Surgery
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• v.38 no.2 s.247
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• pp.101-109
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• 2005

Background: In sudden cardiac arrest, the effective maintenance of coronary artery blood flow is of paramount importance for myocardial preservation as well as cardiac recovery and patient survival. The purpose of this study was to directly compare the effects of pulsatile and non-pulsatile circulation to coronary artery flow and myocardial preservation in cardiac arrest condition. Material and Method: A cardiopulmonary bypass circuit was constructed in a ventricular fibrillation model using fourteen Yorkshire swine weighing $25\~35$ kg each. The animals were randomly assigned to group I (n=7, non-pulsatile centrifugal pump) or group II (n=7, pulsatile T-PLS pump). Extra-corporeal circulation was maintained for two hours at a pump flow of 2 L/min. The left anterior descending coronary artery flow was measured with an ultrasonic coronary artery flow measurement system at baseline (before bypass) and at every 20 minutes after bypass. Serologic parameters were collected simultaneously at baseline, 1 hour, and 2 hours after bypass in the coronary sinus venous blood. The Mann-Whitney U test of STATISTICA 6.0 was used to determine intergroup significances using a p value of < 0.05. Result: The resistance index of the coronary artery was lower in group II and the difference was significant at 40 min, 80 min, 100 min and 120 min (p < 0.05). The mean velocity of the coronary artery was higher in group II throughout the study, and the difference was significant from 20 min after starting the pump (p < 0.05). The coronary artery blood flow was higher in group II throughout the study, and the difference was significant from 40 min to 120 min (p < 0.05) except at 80 min. Serologic parameters showed no differences between the groups at 1 hour and 2 hours after bypass in the coronary sinus blood. Conclusion: In cardiac arrest condition, pulsatile extracorporeal circulation provides more blood flow, higher flow velocity and less resistance to coronary artery than non-pulsatile circulation.

• 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.

• Journal of Chest Surgery
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• v.33 no.4
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• pp.277-284
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• 2000

Background: Coronary artery bypases grafting in the old aged is associated with high mortality and morbidity, and it is difficult to perform if the coronary artery is diffusely disease. Recently it has been known that platelet derived growth factor(PDGF), especially PDGF-BB, stimulates angiogenesis. Material and Method: New Zealand white rabbit were used. In an attempt to achieve effevtive cardiac revasculatrization without vascular anastmosis, we divided into three groups(group I : Left anterior descending artery(LAD) was occluded by ligature, group II : Bilateral internal mammary vascular pedicles were dissected and implanted into myocardium, group III : The vascular pedicles were implanted into myocardium and PDGF-BB was injected into the myocardial tissue). Two weeks after IMA implantation, the proximal region of implanted LAD was ligated. Four days after LAD ligation angiogram, triphenyl tetrazolium chloride(TTD) staining and hematoxylin eosin staining were performed. Result: 1. Survival rate in group II was significantly higher than that in group I (P<0.05), and survival rate in group III was signficantly higher than that in group II(53% vs 93%, P<0.01). 2. There were significant differences in the ratio of area of necrosis to area at risk between group I and group II, and between group II and group III (P<0.01). 3. Microangiogram for angiogenic response revealed wide area of extensive revascularization with patent vessels in group III. 4. Histologic findings of three groups showed that polymorphonuclear leukocyte infiltration was minimal in group II and none in group III. Conclusion: PDGF-BB can establish functinal cardiac revasculatization through systemic vessels implanted directly into the myocardium.

• Journal of Chest Surgery
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• v.30 no.11
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• pp.1132-1135
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• 1997

We have experienced two cases of coronary revascularization without extracorporeal circulation in a 63 year old female patient and a 75 year old male patient. The first patient had the lesion which was the nearly total occulusion of mid-LAD, about 90% luminal narrowing of second diagonal branch and less than 50% stenosis of proximal RCA. The other male patient had a single vessel disease involving about 95% stenosis of proximal LAD and 1st diagonal branch. PTCA failed in the irst patient because of relatively long sinus pause during procedure In both of the patients, the coronary revascularizations were done at distal LAD and diagonal branch using left internal mammary artery and saphenous vein graft under the beating state, respectively. The postoperative courses were uneventful and the patients were discharged without any complications.

• Journal of Chest Surgery
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• v.52 no.1
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• pp.16-24
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• 2019

Background: Optimal graft selection for coronary artery bypass grafting (CABG) in patients with severe left ventricular (LV) dysfunction remains debatable. We report an analysis of our experiences of isolated CABG in patients with severe LV dysfunction and the impact of graft strategy on long-term outcomes. Methods: We analyzed 209 patients with severe LV dysfunction (ejection fraction [EF] <30%) who underwent primary isolated CABG. Of these, 169 were revascularized with a bilateral internal thoracic arterial (ITA) graft (BITA group) and 40 were revascularized with a single ITA graft (SITA group). The mean follow-up duration was $22{\pm}32$ months. Results: There were 18 early deaths (8.6%). Overall survival at 5 years was 66.7%. The rate of freedom from cardiac-related death at 5 years was 74.1%, and was significantly higher in patients who underwent off-pump CABG (p=0.005) and in the BITA group (p=0.023). Multivariate analysis demonstrated that old age (hazard ratio [HR], 2.548; 95% confidence interval [CI], 1.134-5.762; p=0.024), off-pump CABG (HR, 0.245; 95% CI, 0.090-0.661; p=0.006), and BITA grafts (HR, 0.333; 95% CI, 0.146-0.757; p=0.009) were correlated with cardiac mortality. Conclusion: CABG in patients with severe LV dysfunction (EF <30%) showed reasonable long-term outcomes. The rate of freedom from cardiac-related death was significantly higher in patients who underwent off-pump CABG and in the BITA group. Off-pump BITA grafting strategies can be accepted as a viable primary option in patients with severe LV dysfunction if performed by an experienced surgeon.

• Journal of Chest Surgery
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• v.24 no.7
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• pp.637-646
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• 1991

Effect of noradrenaline and endothelium on the high K+ or Ach-induced contraction were investigated in the pig myocardial coronary artery. The helical strip of isolated pig myocardial coronary artery was immersed in the Tris-buffered Tyrode`s solution equilibrated with 100% O2 at 37oC and its isometric tension was measured. High K+ and Ach-induced contraction were dose-dependent. By denuding the endothelium, dose-contraction curve of K+ was not shifted significantly to the left and upward, but that of Ach was shifted significantly to same direction 25 mM K+ - and Ach-induced contraction were relaxed by norepinephrine[NE]. NE-induced relaxation was blocked by the pretreatment of propranolol, which was known as b-adrenoceptor blocker. And, phenylephrine known as a-adrenoceptor agonist, and clonidine known as a-adrenoceptor agonist increased the 25mM K+ - induced contraction respectively. Denuding of endothelium did not show any significant effects on NE-induced relaxation and contraction increased by phenylephrine and clonidine. Tyramine increased 25mM K+ - induced contraction further. The contractile response by tyramine on the 25mM K+ - induced contraction was not blocked by the pretreatment of phentolamine, but was partially blocked by the pretreatment of atropine. From the above results, it is suggested that activation of a1-and a2-adrenoceptors induce the contraction, activation of b-adrenoceptors induce the relaxation, and NE-induced relaxation is mainly due to activation of b-adrenoceptors. Also it is suggested that denudation of endothelium did not influence NE-induced relaxation, but influence Ach-induced contraction in the pig myocardial coronary artery.

• Journal of Yeungnam Medical Science
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• v.32 no.2
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• pp.146-151
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• 2015

Atherosclerotic renal artery stenosis (RAS) may result in hypertension, azotemia, and acute pulmonary edema. We report on a renal angioplasty with stent placement for bilateral RAS in a patient with acute decompensated heart failure and acute kidney injury. A 67-year-old female patient was admitted to our hospital with acute shortness of breath and generalized edema. Echocardiography showed left ventricular wall motion abnormality and the follow up electrocardiography showed T wave inversion in the precordial leads. We performed a coronary angiography to differentiate ischemic heart disease from non-cardiac origin for the cause of the heart failure. The coronary angiography showed no significant luminal narrowing, but bilateral RAS was confirmed on the renal artery angiography, therefore, we performed renal artery revascularization. After the procedure, the pulmonary edema was improved and the serum creatinine was decreased. Two weeks later, an echocardiography showed improvement of the left ventricular systolic function.

• Journal of Chest Surgery
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• v.35 no.1
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• pp.1-10
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• 2002

Background: Despite the relatively high mortality rates in the chronic heart failure model induced by coronary artery ligation are relatively high, this model has been a subject of continuos research because of its clinical correlation. Chronic heart failure model of large-sized animals is very useful to analyse mechanical or biological effects on circulatory system which is difficult in small-sized animals. The purpose of this study is to establish the heart failure model by coronary artery ligation in sheep. Material and Method: Among 9 Corridale sheep, the homonymous artery and the diagonal branch were ligated simultaneously in 2 sheep and remaining 7 sheep were assigned to successive ligation of both arteries at an interval of 1 hour. Both coronary arteries were ligated from the point 40% proximal to the apex of the heart. Hemodynamic and echocardiographic parameters were analyzed before the ligation of the coronary artery, after the ligation of the homonymous artery, and after additional ligation of the diagonal branch. The experimental animals were sacrificed after 2 or 3 months of growth and histopathologic studies were performed Result: Immediate postoperative death occurred in the 2 sheep that had received simultaneous ligation of the homonymous artery and diagonal branch. On the other hand, all the 7 sheep that were lifated in succession were survived up to 3 months. Arterial pressure was sifnificantly decreased immediately after ligation of the homonymous artery(p<0.05), and the cardiac output was decreased and pulmonary capillary wedge pressure was increased after further ligation of the diagonal branch(p<0.05). Central venous pressure, pulmonary artery pressure, pulmonary capillary wedge pressure, left ventricular end-diastolic dimension and end-systolic dimension were markedly increased 3 months after ligation of coronary arteries. Anteroseptal akinesia or dyskinesia was developed after the ligation of coronary arteries. Histopathologic study revealed we]1-demarcated ischemic area of fibrosis. Conclusion: Using methods of successive ligation of the homonymous artery and diagonal branch, chronic heart failure model could be reliably established in sheep.

• 대한핵의학회:학술대회논문집
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• 2000.05a
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• pp.76.1-76.1
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• 2000

• Korean Circulation Journal
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• v.52 no.12
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• pp.906-907
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• 2022