• Journal of Chest Surgery
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• v.36 no.4
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• pp.255-260
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• 2003

Background: Stenosis of the left pulmonary artery (LPA) after repair of tetralogy of Fallot (TOF) is troublesome. A new technique of LPA angioplasty using an autologous MPA flap was performed in patients with TOF Material and Method: From October 1998 to January 2001, 24 patients (median age; 10 months, range; 4 to 145 months) underwent total correction of TOF with LPA angioplasty using the autologous MPA flap. Five patients underwent pulmonary angioplasty without any patch over the MPA and LPA. The patches were required to enlarge only the MPA in 4 patients, and transannular RVOT widening was performed in 15. Result: There were no operative or late deaths. During follow-up (range: 6~42 months), reoperation for LPA stenosis was not required in any patients, but balloon angioplasty for branch pulmonary artery stenosis was performed in 3 patients. Echocardiography and CT angiography at the recent follow-up showed an obtuse angle between the MPA and LPA. Conclusion: Although further follow-up is needed, the angioplasty using the autologous MPA flap can be easily performed, avoiding patch-related complications, and allowing growth of the MPA flap. This angioplasty technique creates a more natural and obtuse angle between the MPA and LPA, which can minimize kinking of the LPA, especially in the patients who underwent transannular patch widening.

• Journal of Chest Surgery
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• v.41 no.4
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• pp.476-479
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• 2008

The Rastelli operation has been a standard procedure for repairing complete transposition of the great arteries combined with a ventricular septal defect and pulmonary stenosis. Yet this procedure has several shortcomings, including the risk of incurring left ventricular outflow tract obstruction on long-term follow-up. In this regard, aortic translocation has recently been regarded as a potent alternative to Rastelli's operation. We report here on a case of complete transposition of the great arteries that was combined with an inlet-extended perimembranous ventricular septal defect and pulmonary stenosis in a 2-year-old boy. All the problems were successfully repaired using the aortic translocation technique. Postoperative echocardiography showed a straight and wide left ventricular outflow tract.

• Journal of Chest Surgery
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• v.37 no.9
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• pp.727-734
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• 2004

The Lecompte procedure for transposition of the great arteries has an advantage because it obviates the need for an extracardiac conduit for the reconstruction of the pulmonary outflow tract. We evaluated the effectiveness and the application of the Lecompte procedure. Material and Method: A retrospective review was conducted of the records of 46 patients who underwent the Lecompte procedure during the past 15 years. Mean age at operation was 29.2$\pm$20.3 (range: 3∼83) months. The diagnoses involved anomalies of the ventriculoarterial connection with ventricular septal defect and pulmonary outflow tract obstruction, such as transposition of the great arteries, double-outlet right ventricle, and double-outlet left ventricle. Result: Early mortality was 4.4% (2 of 46 patients) and late mortality was 6.8% (3 of 44). The mean follow-up was 11.2$\pm$6.9 years. Eighteen patients (43.9% of survivors, n=41) had pulmonary stenosis (pressure gradient above 30 mmHg), the main reason for which was a calcified monocusp valve (n=15, 83.3%). Seventeen of 46 patients (37.0%) underwent reoperation: 15 for pulmonary stenosis, 5 for residual ventricular septal defect, 4 for left ventricular outflow tract obstruction, 3 for pulmonary insufficiency, and 4 for other causes. The cumulative survival rates were 91.3$\pm$4.2%, and 87.0$\pm$5.8% at 10 and 15 years, respectively. The actuarial probabilities of freedom from reoperation for pulmonary stenosis were 90.6$\pm$4.5%, 73.9$\pm$7.3%, and 54.0$\pm$10.4% at 5, 10, and 15 years, respectively. Conclusion: The Lecompte procedure is an effective treatment modality. Repair in early age is possible with acceptable morbidity and mortality, but recurrent right ventricular outflow tract obstruction caused by degeneration of the monocusp valve is a problem that needs resolution.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1991.06a
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• pp.25-25
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• 1991

최근 교통사고의 증가, 심폐술의 보편화 및 보조호흡을 필요로 하는 환자의 증가에 따라 경구적 혹은 기관절개술을 통해 기관내 삽관을 장기간 유치하는 경우가 많아져서 이에 따른 합병증으로 기관협착증의 빈도가 높아지게 되었다. 기관내 삽관후 기관협착증을 초래하는데에는 관의 외경, 삽관시 외상, 삽관유치기간, 기계적 보조호흡시 관의 이동, cuff 의 압력 등의 요인이 작용한다. 이러한 요인에 의해 기관내 삽관을 장기간 유치시 기관점막에 대한 지속적인 압박으로 점막하부의 압박괴사 및 혈관의 폐쇄로 인해 기관연골의 무혈성 괴사를 초래하여 환상의 기관협착이 병발하게 된다. 기관협착증에 대한 치료방법으로서는 여러 가지가 있으나 환상의 기관협착증인 경우는 협착부위의 절제 및 단단문합술을 시행하고 절제부위가 광범위한 경우는 release technique 을 이용하여 문합부위의 장력을 줄여주는 것이 효과적인 치료방법으로 알려져 있다. 저자들은 최근 기관내 삽관후에 병발한 환상기관협착증 3례(다발성 골절 1례, 기관지 천식 1례, 약물중독 1례)에 대해 기관절제 및 단단문합술을 경험하였기에 보고하고자 한다.

• Investigative Magnetic Resonance Imaging
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• v.13 no.2
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• pp.152-160
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• 2009

Purpose : To intra-individually compare diagnostic accuracy of high-resolution contrast-enhanced magnetic resonance angiography (CE-MRA) with computed tomography angiography (CTA) and digital subtraction angiography (DSA) for the assessment of supraaortic steno-occlusive disease. Materials and Methods : Twenty-eight patients (20 men, 8 women, 53-79 years of age) underwent supraaortic CE-MRA, CTA and DSA. CE-MRA was performed on two 1.5T MR scanners (voxel dimension: $0.66{\times}0.66{\times}1.1$ or $1.2\;mm^3$), and CTA on 64-slice CT scanners (voxel dimension: $0.42{\times}0.42{\times}0.63\;mm^3$). All the three examinations were completed within 40 days (median 19 days; range 1-40 days). Retrospective evaluation and measurement of diameter of 6 extracranial and 9 intracranial arterial segments was done by 2 experienced radiologists. Results: A total of 420 arterial segments were examined by CE-MRA, CTA and DSA. On DSA, 34 stenoocclusive lesions were noted at extracranial (n= 19) and intracranial (n = 15) vessels. For extracranial stenosis greater than 70%, sensitivity, specificity, positive predictive value (PPV) and negative predictive values (NPV) were 94.7%, 98.7%, 90.0% and 99.3% on CE-MRA, and 94.7%, 99.3%, 94.7% and 99.3% on CTA. For intracranial stenosis greater than 50%, sensitivity; specificity, PPV and NPV were 93.3%, 98.3%, 77.8%and 99.6% on CE-MRA, and 86.7%, 97.9%, 72.2% and 99.1 % on CTA, with DSA as the standard of reference. Conclusion : Supraaortic CE-MRA is as reliable as CTA in depicting the arterial stenosis, and is effective in screening of significant stenosis of both extracranial and intracranial arterial stenosis.

• Journal of Chest Surgery
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• v.35 no.9
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• pp.688-691
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• 2002

Takayasu's arteritis is a chronic inflammatory disease of unknown cause. It predominantly affects the aortic arch and its branches. Concomitant involvement of coronary and renal arteries is a rare entity. In this report, we described successful treatment of a patient with Takayasu's arteritis associated with coronary and renal arteries stenosis. A 23-year-old woman was presented with chest pain on exertion. Angiographic studies demonstrated left main coronary, bilateral renal, and left subclavian arteries stenosis. She underwent angioplasty and stenting of bilateral renal artery. After one week, coronary artery bypass grafting using greater saphenous veins and aorto-subclavian bypass with PTFE vascular graft were done simultaneously. She was discharged on the 13th postoperative day without any complications.

• 대한핵의학회:학술대회논문집
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• 1999.05a
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• pp.205-208
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• 1999

Percutaneous Transluminal Coronary Angioplasty (PTCA) remains limited by restenosis that occurs in 30 to 50% of patients with coronary artery disease. During the last decade, numerous agents have been used to prevent restenosis. Despite positive results in animal models, no pharmacological therapy has been found to significantly decrease the risk of restenosis in humans. These discrepancies between animal models and clinical situation were probably related to an incomplete understanding of the mechanism of restenosis. Neointimal thickening occurs in response to experimental arterial injury with a balloon catheter. Neointimal formation involves different steps: smooth muscle cell activation, proliferation and migration, and the production of extracellular matrix. The factors that control neointimal hyperplasia include growth factors, humoral factors and mechanical factors. Arterial remodeling also plays a major role in the restenosis process. Studies performed in animal and human subjects have established the potentials for "constrictive remodeling" to reduce the post-angioplasty vessel area, thereby indirectly narrowing the vessel lumen and thus contributing to restenosis. The reduction of restenosis rate in patients with intracoronary stent implantation has been attributed to the preventive effect of stent itself for this negative remodeling. In addition to these mochanisms for restenosis, intraluminal or intra-plaque thrombus formation, reendothelialization and apoptosis theories have been introduced and confirmed at least in part.

• Journal of Biomedical Engineering Research
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• v.23 no.4
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• pp.281-286
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• 2002

In this study, blood flow in a carotid artery supplying blood to the human's brain has been numerically simulated to find out how the blood flow affects the genesis and the growth of atherosclerosis and arterial thrombosis. Velocity Profiles and hemodynamic parameters have been investigated for the carotid arteries with three different stenoses under physiological flow condition. Blood has been treated as Newtonian and non-Newtonian fluid. To model the shear thinning properties of blood for non-Newtonian fluid, the Carreau-Yasuda model has been employed. The result shows that the wall shear stress(WSS) increases with the development of stenosis and that the wall shear stress in Newtonian fluid is highly evaluated compared with that in non-Newtonian Fluid. Oscillatory shear index has been employed to identify the time-averaged reattachment point and this point is located farther from the stenosis for Newtonian fluid than for non-Newtonian fluid The wall shear stress gradient(WSSG) along the wall has been estimated to be very high around the stenosis region when stenosis is developed much and the WSSG peak value of Newtonian fluid is higher than that of non-Newtonian fluid.

• Proceedings of the KTCVS Conference
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• 1995.10a
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• pp.38-38
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• 1995

• 순환기질환의공학회:학술대회논문집
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• 2006.10a
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• pp.40-41
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• 2006