• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1998년도 추계학술대회
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• pp.247-248
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• 1998

The effect of unattached valve leaflet on flow field downstream of a floating and flapping polyurethane heart valve prosthesis was investigated. With a triggering system and a time-delay circuit the instantaneous velocity field downstream of the valve was measured by particle image velocimetry (PIV) in conjunction with the opening posture of a flexible valve leaflet during a cardiac cycle. Reynolds shear stress distribution was calculated from the velocity fields and wall shear stress was directly measured by hot-film anemometry (HFA). The floating motion of the valve leaflet resulted in the reduction of pressure drop and recirculating flow region downstream of the valve.

• Journal of Chest Surgery
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• 제46권4호
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• pp.256-264
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• 2013

Background: Surgical treatment of infective endocarditis (IE) remains a challenge, especially in cases of multiple valve surgery. We evaluated the clinical outcomes of native valve IE and compared the outcomes of single valve surgery with those of multiple valve surgery. Materials and Methods: From 1997 to 2011, 90 patients underwent surgery for native valve IE; 67 patients with single valve surgery (single valve group) and 23 patients with multiple valve surgery (multiple valve group). The mean follow-up duration was $73.1{\pm}47.4$ months. Results: The surgical mortality in the total cohort was 4.4%. The overall survival (p=0.913) and valve-related event-free survival (p=0.204) did not differ between the two groups. The independent predictor of postoperative complications was New York Heart Association class (p=0.001). Multiple valve surgery was not a significant predictor of surgical mortality (p=0.225) or late mortality (p=0.936). Uncontrolled infection, urgent or emergency surgery, and postoperative complications were identified as independent predictors of valve-related morbidity, excluding multiple valve surgery (p=0.072). Conclusion: In native valve IE, multiple valve surgery as a factor was not an independent predictor of mortality and morbidity. The number of surgically corrected valves in native IE seems to be unrelated to perioperative and long-term outcomes.

• Journal of Chest Surgery
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• 제36권9호
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• pp.687-690
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• 2003

비상관성 심실중격결손을 동반한 양대혈관 우심실기시증의 수술적 교정방법은 형태학적 특징에 따라 다양하지만 삼첨판 건삭이 원추부 중격에서 기시를 하는 경우와 삼첨판막에서 폐동맥판막까지의 거리가 좁아서 그 사이로 첨포가 지나가기 힘든 경우는 특히 양심실성 교정이 매우 어렵다. 본원에서는 원추부 중격에서 기시하는 삼천판 건삭이 존재하고 삼첨판막과 폐동맥판막사이의 거리가 좁은 비상관성 심실중격결손을 동반한 양대혈관 우심실기시증 환자에서 심실중격결손부에서 폐동맥으로 첨포를 연결하고 동맥전환술을 함으로써 양심실성 교정을 성공적으로 시행하였기에 증례 보고하는 바이다.

• Journal of Chest Surgery
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• 제13권4호
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• pp.375-384
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• 1980

Since 1958 up to the end of October 31, 1980, 2032 cases of cardiovascular lesions were operated, including 1225 open heart surgery and 354 valve replacement patients. There were 1271 Congenital anomaly cases and 761 acquired lesions including 149 vascular lesions. Among 1~271 congenital malformations 819 cases belong to acyanotic and 452 to cyanotic group. Over all mortality was 11.1 %, consisting of 12.4% for congenital and 8.9% for acquired lesions. Mortality for 1225 open heart surgery cases was 15% and 13.8% for various 354 valve replacement cases. In most of the open heart surgery cases Shiley oxygenator was utilized and Ionescu-Shiley bovine pericardial xenograft bioprosthesis**** valves were used mainly for valve replacement.

• 한국임상수의학회지
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• 제37권3호
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• pp.153-156
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• 2020

A 14-year-old intact female Cocker Spaniel dog, weighing 6.8 kg, presented with chief complaints of severe cough, dyspnea, anorexia, and exercise intolerance. It had the characteristics of a blood clot, the evidence of mitral regurgitation, a high left atrial/aortic root ratio, and pericardial effusion with a left atrial rupture due to myxomatous mitral valve degeneration (MMVD) was strongly suspected. Traditional therapy (pimobendan, furosemide, enalapril, and spironolactone) for heart failure with MMVD was provided twice a day orally, and partial pericardiectomy was performed for pericardial effusion. The medical prescriptions for MMVD were continued, and the patient's heart disease was well-controlled. However, it suddenly died 3 months after the operation.

• 한국정밀공학회지
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• 제22권3호
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• pp.154-161
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• 2005

In this study, the leaflet motion of a mechanical heart valve and the characteristics of two-dimensional transient blood flow in an elastic blood vessel have been numerically investigated by using fluid-structure interaction method. Here, blood has been assumed as a Newtonian, incompressible fluid. Pressure profiles have been used as boundary conditions at the ventricle and the aorta. As a result, closing motion of the leaflet is faster than opening one. While opening angles of leaflet grow up, vortex is detected at the sinus and backward of the leaflets. When the leaflet is fully closed, vortex is detected at the ventricle and at that moment maximum displacement of the elastic blood vessel is observed in the vicinity of the sinus region. Maximum displacement is caused in association with the blood flow that is oriented toward the elastic blood vessel.

• Journal of Chest Surgery
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• 제30권10호
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• pp.1015-1018
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• 1997

개심술 특히 판막 질환의 수술에 있어서 정중 흉부 절개의 방법은 현재까지 가장 널리 사용되는 절개 방 법이다 그러나 최근 들어 판막 질환의 수술시 우측 흉골외측 절개를 이용하여 절개부위를 최소화함으로서 많은 장점을 가질 수 있는 방법이 보고되고 있다. 고려대학교 부속 구로병원에서는 우측 흉골외측 절개와 심방 중격 절개를 이용하여 1례의 승모판막 치환 술을 시행하였는데, 이 방법의 사용시 기존의 정중 흉부 절개의 방법과 비교하여 특이한 합병증이나 어려움 을 경험할 수는 없었고,훌릉한 수술 시야를 확보할 수 있었으며,환자는 수술 절개 부위에 대하여 미용적인 면에서 매우 만족하였다.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1997년도 춘계학술대회
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• pp.51-54
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• 1997

Lumbrokinase, potent fibrinolytic enzyme purified from earthworm, was immobilized onto the total artificial heart valves using photoreaction. This valve were implanted into the lamb for three days. After experiments, thrombus was observed in the untreated valves whereas no thrombus was observed in the lumbrokinase immobilized valves. The fibrinolytic activity and proteolytic activity of the implanted valve was examined. The fibrinolytic activity of the valve was remained after the implantation. The lumbrokinase could be a suitable fibrinolytic agents in the vascular contacting devices to reduce the thrombus.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2004년도 추계 학술대회논문집
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• pp.203-206
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• 2004

In this study, a numerical analysis has been performed for a three-dimensional pulsatile blood flow associated with the elastic blood vessel and curved bileaflet for multiple cycles in terms of fluid-structure interaction. Here, blood has been assumed as a Newtonian, incompressible fluid. Pressure profiles have been used as boundary conditions at the ventricle and the aorta. From this analysis, the motion of the leaflet has been observed with fluttering phenomenon and rebound, and the flow fields of blood have been obtained with recirculation and regurgitation. The results can contribute to the development of design methodology for the curved bileaflet mechanical heart valve.

• Journal of Chest Surgery
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• 제37권10호
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• pp.876-879
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• 2004

일반적으로 폐질환과 심장 질환이 동시에 발견되었을 때 동시 수술은 술자가 고려해야 되는 사항이 많다. 59세 여자 환자가 우중엽절제술과 이중판막 재치환술과 삼첨판막륜성형술을 동시에 시행 받았다. 동시 수술은 폐와 심장의 병변을 일거에 해소하면서 2차적으로 시행해야 하는 폐절제술 또는 심장수술에 따르는 위험성을 피할 수 있는 장점이 있으며 안전하게 시행할 수 있는 술식이다.