• Journal of Chest Surgery
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• 제19권1호
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• pp.75-82
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• 1986

The use of the Angell-Shiley porcine xenograft cardiac valve was limited in number at Seoul National University Hospital chiefly because of the cessation of supply from the manufacturer, Forty-eight Angell-Shiley valves along with the 5 other mechanical or tissue valves were used in 46 patients during the period from 1977 to 1980, and a total of consecutive cases was studied for their early and long-term clinical results. The operative mortality rate was 4.3%; no death after single and 2 deaths after double valve replacement within 30 days of surgery. The 44 early survivors were followed up for a total of 171.6 patient-years and a mean of 46.8$\pm$31.1 months. Four died during the follow-up period with a linealized late mortality rate of 2.33%/patient-year. Four patients had experienced 5 episodes of thromboembolism and one died; a linealized incidence of 2.91% emboli/patient-year. A single case each had a bleeding complication related to the anticoagulants, 0.58% bleeding/patient-year, and prosthetic valve endocarditis, 0.58% endocarditis/patient-year. The clinical improvement was excellent by 70% of the survivors having no cardiac symptoms at the end of the follow-up. The actuarial survival rates were 89.9$\pm$4.9% at 5 years and 69.2$\pm$15.0% at 9 years after surgery. The probabilities of freedom from thromboembolic complication were 92.3$\pm$5.5% and 80.9$\pm$9.0% at 5 and 9 years after surgery. And, the probability of freedom from overall valve failure was 83.4$\pm$6.3% at 5 years and it declined sharply down to 55.9$\pm$22.2% at 9th year of the follow-up. These results are comparable with those in the major reports, except a more accelerated and time-related increases in valve failure after 5 or 6 years after operation with the Angell-Shiley valve. The durability of the xenograft tissue valve remains as the most important debate and the need of more durable tissue valves was also discussed.

• Journal of Chest Surgery
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• 제19권1호
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• pp.83-91
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• 1986

The Carpentier-Edwards porcine xenograft valve was used in 21 patients at Seoul National University Hospital during the period between 1977 and 1979. Twenty-four Carpentier-Edwards valves were implanted along with 2 others. Three patients died within 30 days of operation, an operative mortality rate of 14.3%. Eighteen early survivors were followed up for a total 67.5 patient-years [mean, 45.0$\pm$32.0 months]. There were 2 late deaths with a linealized late mortality rate of 2.96%/patient-year; one died from cerebral bleeding [1.48% bleeding/patient-year] and the other from prosthetic valve endocarditis [1, 48% endocarditis/patient-year]. There was no case of thromboembolism. Two patients developed mitral regurgitation [2.96% failure/patient-year]. Symptomatic improvement was excellent. The actuarial survival rate and the probability of freedom from overall valve failure were 75.3$\pm$9.6% and 80.7$\pm$12.9% at 9 years after surgery respectively. During the period from October, 1968, through June, 1985, 1, 190 substitute heart valves were used in a total of 967 patients at Seoul National University Hospital; of which, 90.9% were either porcine aortic or bovine pericardial xenograft valves. For the evaluation of the xenograft tissue valves, the consecutive patients with lonescu-Shiley valve in the mitral, aortic and both positions, Angell-Shiley valve and Carpentier-Edwards valve were recently studied on the clinical ground. They were 531 patients, and 643 xenograft valves were used. The operative mortality rate was 6.97% and a linealized late mortality rate 2.94%/patient-year. A total of 490 early survivors were followed up for 917.6 patient-years [mean, 22.5 months], and 70% of patients completed the follow-up. The linealized incidences of complications were: 2.29% emboli/patient-year, 1.98% bleeding/patient-year, 1.20% endocarditis/patient-year, and 3.49% failure/patient-year. These clinical resutls are fully comparable with those in the major reports. The durability of the glutaraldehydepreserved xenograft heart valves remains as a great concern and a continuing debate, expecially for the group of patients in the pediatric age. The need of more durable material for the improved tissue valves was also discussed.

• 한국추진공학회지
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• 제13권1호
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• pp.1-9
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• 2009

본 논문에서는 러시아에서 출간된 문헌들의 검토를 통하여 액체로켓엔진에 대한 시험-개선과정의 방법론적 측면을 고찰하였다. 그리고 러시아와 미국의 개발경험을 기초로 액체로켓엔진에 대한 시험-개선과정의 특징과 합리적인 실현방법을 명확히 하였다. 액체로켓엔진의 개발에 있어서 요구되는 수준의 신뢰도를 성취하고 물적 지출을 줄이기 위한 시험-개선과정의 행정 및 기술적인 해결법이 제시되었으며, 이와 같은 해결 방법들은 국내에서 개발되고 있는 액체로켓엔진에 적용될 수 있다.

• Radiation Oncology Journal
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• 제21권4호
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• pp.253-260
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• 2003

목적: 흉벽을 침범한 PT3N0 비소세포폐암 환자에서 수술 후 방사선치료를 추가하는 것이 필요한지의 여부와 적절한 방사선치료의 조사영역에 관해서는 아직 정립된 이론이 없다. 본 연구에서는 종양으로부터 수술 절제연까지 충분한 여유를 얻기가 힘들었던 소견으로 방사선치료를 추가한 흉벽침범 pT3N0 비소세포폐암 환자들에 대한 후향적 분석을 수행하였다. 대상 및 방법: 1994년 8월부터 2002년 6월까지 성균관의대 삼성서울병원에서 흉벽침범 pT3N0 비소세포폐암으로 수술 후 방사선치료를 추가한 환자는 모두 21명이었다. 모든 환자들은 근치적 폐절제술과 흉벽절제술과 함께 동측 폐문 및 종격동 림프절 곽청술을 시행받았다. 방사선치료는 수술 3$\~$4주 후에 시작하여 선택적 림프절 방사선조사를 고려하지 않고 원발종양에 의해 침범된 흉벽과 그 주변 조직에만 국한하여 최소 54 Gy를 조사하도록 예정하였다(1회선량 1.8$\~$2.0 Gy, 주 5회 치료). 환자들의 생존율과 재발양상을 후향적으로 분석하였다. 결과: 전체 환자의 5년 생존율, 무병생존율, 국소종양억제율, 무원격전이 생존율은 각각 38.8$\%$, 45.5$\%$, 90.2$\%$, 48.1$\%$였다. 모두 11명의 환자에서 치료실패를 경험하였는데, 원격전이가 6명, 흉곽내재발이 3명, 원격전이와 흉곽내재발의 동시재발이 2명이었다. 흉곽내재발 환자 5명 중 방사선치료 조사영역 내에서의 국소재발은 2명, 늑막파종이 2명, 종격동 림프절 재발이 1명이었다. 방사선치료와 관련되는 RTOG 3등급 이상의 급성 및 만성 부작용은 없었다. 결론: 흉벽침범 pT3 비소세포폐암의 치료성공에 있어 가장 중요한 요소는 완전절제를 통한 국소제어인바, 수술 소견상 충분한 여유 절제연의 확보가 불가능한 경우 수술 후 방사선치료를 추가하여 국소제어율을 높이도록 도모하는 것은 충분한 당위성을 갖는다. 또 방사선치료 조사영역의 결정에 있어서도 선택적 림프절 방사선조사를 배제함으로써 영역림프절 재발의 과도한 위험부담 없이도 급성 및 만성 부작용의 위험을 현저히 감소시켜 환자의 삶의 질을 향상시킬 수 있었다.