• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1995년도 추계학술대회
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• pp.57-60
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• 1995

The objective of this investigation is to understand the role of hemodynamics in the formation and development of atherosclerosis lesions in the human left coronary artery This study also aims to compare the blood flow characteristics of steady and physiological flows. Three dimensional, steady and physiological flows of blood in the left coronary artery are simulated using the Finite Volume Method. Apparent viscosity of blood is represented as a function of shear rate by the Carreau model. Distributions of velocity, pressure and shear stress in tile left coronary artery bifurcation are presented to compare tile steady and physiological flow characteristics.

• Journal of Chest Surgery
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• 제24권4호
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• pp.361-365
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• 1991

We experienced one case of the coronary artery aneurysm. The patient was 67 years old female, who complained of dyspnea on exercise[NYHA functional class III] for two years. Coronary angiogram demonstrated a localized saccular aneurysm on left main coronary artery, just above bifurcation of left anterior descending coronary artery and circumflex artery. On the operative field, the aneurysm was 2cmx2cmx 1.5cm in size with 0.5cm in neck. Resection and aneurysmorrhaphy was done. The patient was recovered and discharged uneventfully. During 8 months follow-up period, she lives in good physical activity and absence of chest pain.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1997년도 춘계학술대회
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• pp.111-115
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• 1997

The objective of present study is to obtain information about stenosis effects on the blood flow in the coronary artery bifurcation. The three dimensional steady of blood in the coronary artery bifurcation with stenosis and without stenosis are simulated using the finite volume method. Apparent viscosity of blood is represented as a function of shear rate by the Carreau models. Velocities vectors and wall shear stresses along the branch tubes with stenosis are compared with those of without stenosis for steady flows. Flow phenomena in the stenosed branch tubes are discussed extensively.

• Journal of Medicine and Life Science
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• 제20권3호
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• pp.131-134
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• 2023

Here, we present a case of a 56-year-old man with acute myocardial infarction. The patient underwent percutaneous coronary intervention (PCI) at the left main bifurcation and mid-left anterior descending artery using drugeluting stents. Four months after the PCI, the patient was readmitted for cardiac arrest. Coronary angiography (CAG) revealed stent thrombosis in the left main-to-proximal left anterior descending artery and in-stent restenosis in the left main-to-proximal left circumflex artery. We performed balloon angioplasty at the left main to mid-left anterior descending artery and left main to proximal left circumflex artery stents; subsequently, blood flow was fully restored. However, contrast agent extravasation was observed outside the mid-portion of the left main artery to the proximal left anterior descending artery stent, indicating the presence of a coronary artery aneurysm (CAA) outside the stent. After guideline-directed medical therapy with dual antiplatelet agents and high-intensity statins, follow-up CAG revealed near-resolution of the CAA, absence of stenotic lesions, and good blood flow.

• Journal of Chest Surgery
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• 제18권2호
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• pp.214-219
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• 1985

It is well known that the morphologic feature of coronary artery is variant as finger print. Left coronary artery is divided into the left anterior descending artery and circumflex artery and supplies almost left atrium, left ventricle and interventricular septum. Clinically, the morphologic features of number of branches and the length of the left main coronary artery are important. In Korea, there are few reports about morphologic study of the coronary artery, and the coronary angiogram and open heart surgery are common. Now the author studied the morphology of the proximal part of the left coronary artery in Korean 50 Adult cadavers and obtained the following results: 1. The length of the left main coronary artery is from 5 mm to 16 mm [mean 9.7 mm]. 2. The diameter of the proximal part of the left coronary artery is from 3.2 mm to 7.7 mm [mean 5.3]. 3. The features of the branching are bifurcation [58%] trifurcation [38%] and quadrifurcation [4%]. 4. The diameter of the left anterior descending artery is from 2.7 mm to 8.1 mm [mean 4.5] and circumflex artery from 2.1 mm to 6.2 mm [mean 3.9].

• Journal of Chest Surgery
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• 제28권3호
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• pp.320-323
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• 1995

We report a case of recurred Takayasu,s arteritis.The patient was 28-year-old female underwent aorto-left common carotid and aorto-left subclavian bypass graft replacement 1 year ago.Unfortunately, she was readmitted because of newly developing angina and both eye claudication severe headache. Aorto-coronary angiogram showed complete obstruction of left common carotid artery ,stenosis of right carotid artery bifurcation and ostial stenosis of right coronary artery.Bilateral carotid arteries bypass graft with great saphenous vein and right coronary artery bypass graft with right internal mammary artery were done at same the time and she discharged after 21 days without any problem.

• Journal of Chest Surgery
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• 제33권6호
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• pp.512-517
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• 2000

Background: Onlay vein patch coronary angioplasty has been known to be an option for coronary artery stenosis in the selective iesions Material and method: During the period between July 1997 and August 1999, coronary angioplasty using autologous saphenous vein was done on 16 sites in 14 cases for the stenotic lesion at the bifurcation area and significantly stenosis distal to anastomosis. Result: Early patency of the angioplasty site was 85.7% at postoperative day 7. There was no statistically difference in graft patency, operative parameters, and complications compared to conventional anatomosis(p>0.05). Conclusion: Despite the small number of cases, the patency rate of the coronary patch angioplasty was comparable to the conventional CABG. Coronary artery only patch angioplasty could be performed in highly selected coronary arteries.

• 한국정보통신학회논문지
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• 제15권9호
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• pp.2013-2018
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• 2011

관상동맥 성형술과 관상동맥 우회술은 심근경색의 치료를 위해서 널리 이용되고 있는 방법이다. 특히 이 시술을 위해서 혈관의 협착 부위를 정확히 진단하는데 많은 어려움이 있다. 이러한 문제점을 개선하기 위해서 여러 연구자들에 의해서 에지 추출을 이용한 혈관의 협착부위를 검출하는 연구가 진행되고 있다. 그러나 이러한 방법들은 혈관의 구조나 영상의 질에 따라 그 성능의 차이가 발생한다. 따라서 본 연구는 이러한 문제점을 개선하기 위해 새로운 알고리즘을 제안한다. 제안된 알고리즘은 다중 샘플링과 쓰레쉬홀드, 퍼지 알고리즘을 이용한 혈관의 분기점과 끝점, 협착 부위를 검출하는 방법으로 구성되어 있다. 제안된 알고리즘의 성능을 평가하기 위해 다양한 혈관조영영상을 사용하였으며 그 결과 제안된 알고리즘에 의한 혈관의 분기점 및 끝점, 협착 부위 검출에 효과적이었다.

• Journal of Chest Surgery
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• 제26권2호
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• pp.148-153
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• 1993

To compare two methods of mammary pedicle graft preparations with free internal mammary artery flow, we studied 31 patients who had the left internal mammary artery harvested for coronary artery bypass grafting. The free flow was measured at the transected opening of 2 to 3 cm distal to the point of bifurcation on mean arterial pressure of 50 to 55 mmHg during cardiopulmonary bypass. Group I comprised 14 patients, whose grafts were sprayed and wrapped in sponges soaked in diluted papaverine solution (60 mg in 40 ml Hartmann's solution). An average 80 minutes after the preparations, free flow of the internal mammary artery ranged from 20 to 80 ml/min (mean 37.7 ml/min). Group II comprised 17 patients, who had internal mammary artery takedown under the exact conditions used in group I. The grafts were sprayed and wrapped in sponges soaked in the diluted papaverine solution as in group I. After an average of 28 minutes, free flow ranged from 8 to 28 ml/min (mean 17.6 ml/min). Intraluminal papaverine of the same dilution was then injected without any hydrostatic dilatation and flows increased upto 37 to 150 ml/min (mean 74.7 ml/min). This study shows that intraluminal papaverine preparation method markedly increases free mammary artery flow which is inadequate with external papaverine preparation.

• 대한기계학회논문집B
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• 제36권2호
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• pp.153-159
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• 2012

협착이 발생된 관상동맥의 치료를 위해 외과적인 수술방법으로는 이식우회로술이 많이 사용된다. 이식우회로술 시술 시 개존율 향상을 위해서는 최적의 혈관 문합 시술에 대한 연구가 필요하다. 본 연구의 목적은 Y-grafting bypass 와 T-grafting bypass 시술의 효과와 분지각도 및 문합각도 변화에 따른 문합효과를 분석하였다. 이를 위해 기하학적 형상을 최적화하고 각각의 기하학적 형상에 대해 혈류역학적 특성을 비교분석하였다. 이식혈관의 분지각도와 문합각도가 각각 $30^{\circ}$와 $15^{\circ}$일 경우에 LAD 와 LCX 쪽 모두 혈류량이 고르게 분배됨을 확인하였다.