• 제목/요약/키워드: Bypass Ratio

검색결과 156건 처리시간 0.025초

말초동맥질환의 외과적치료 -55예의 임상분석- (Surgical Treatment of Peripheral Arterial Disease -Clinical Analysis Of 55 Cases-)

  • 김한용
    • Journal of Chest Surgery
    • /
    • 제24권12호
    • /
    • pp.1173-1184
    • /
    • 1991
  • This report is a review of 55 cases of peripheral arterial disease, who were treated at the department of thoracic and cardiovascular surgery, Masan Koryo General Hospital from January, 1986 to December, 1990. The result are summerized as follows ; 1. The incidence of peripheral arterial disease were as follows that : Arterial injury was in 21 cases(38.2%), arteriosclerosis oblitrans 18cases(32.7%), thromboembolism 9cases(16.4%), Buerger's disease was in 7cases(12.7%). 2. Overall male to female ratio was 6.8 : 1, the prevalent age was 3rd and 4th decade in arterial injury, 7th and 8th decade in atherosclerosis and thromboembolism and 5th and 6th decade in Buerger's disease. 3. The farmer was the first ranked occupation of these patients with chronic occlusive arterial disease, which was composed of 17 cases (68%). 4. 23 cases of patients with chronic occlusive disease has been smoking and most of them have been smoking over 10 years. 5. The clinical symptoms in acute and chronic arterial obstruction were pain, claudication, gangrene and coldness in order. 6. The duration of symptom of chronic arterial occlusive disease was less 1 years in 15 cases(60%). 7. The lower extremity were more affected than upper extremity in peripheral arterial disease. 8. The cause of arterial injury was traffic accident 9 cases(42.9%) stab wound 8 cases (38.1%), postangiography 2 cases(9.5%) and belt injury 1 case. 9. The etiologic factors of acute arterial occlusion was arterial fibrillation myocardial ischemia and postangiography in order. 10. Lumber sympathectomy in Buerger's disease, artificial bypass graft in atherosclerosis and thromboembolctomy in thromboembolism, end to end with vein graft in arterial injury were performed frequently. 11. Conclusively overall result was satis factory but 3 cases was below knee amputated after operation of chronic arterial occlusive disease.

  • PDF

토끼 내유동맥의 심근이식에서 혈관재형성 촉진에 대한 혈소판 유래 성장인자의 효과 (The Effect of Platelet Derived Growth Factor on the Myocardial Revascularization in Implantation of Rabbit Internal Mammary Artery)

  • 김용환;나석주;정상훈;문석환;조건현;왕영필;김세화;곽문섭
    • Journal of Chest Surgery
    • /
    • 제33권4호
    • /
    • pp.277-284
    • /
    • 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.

  • PDF

소아에서 개심술후 정중흉골절개의 지연흉골폐쇄에 의한 심장압박 방지효과 (Cardiac Decompressing Effect by Delayed Sternal Closure Following Open Heart Surgery in Children)

  • 김경환;서경필
    • Journal of Chest Surgery
    • /
    • 제30권12호
    • /
    • pp.1167-1174
    • /
    • 1997
  • 저자들은 1991년부터 1996년까지 5년간 지연 흉골 폐쇄를 시행한 20명의 환자를 분석하고 추적 조사 하였다. 남녀비는 11:9였고 평균연령은 6.4개월(범위 7일-5년)이었다. 적응증으로는 개심술후 심근부종에 기인한장치한 불안정한 혈역학적 상태로 인한 것이 15례로 가장 많았고, 심폐기 이탈 불가로 심실 보조 장치를 경우에서가 3례, 폐동맥 밴딩술 후 저산소증으로 인한 것이 2례 등이었다. 흉골 봉합은 술후 평균 102시간(범위 4-213시간)에 이루어졌으며 시행 후 중심 정맥압의 유의한 상승이 관찰되었다. 종격 동염, 환부 감염 등은 없었으며 2례에서 패혈증이 관찰되었다. 5명이 사망하였고 생존환자 15명중 2명 이 술후 추적관찰 기간 중 사망하였다. 누적 생존률은 1년과 2년에서 각각 65.0%였다. 지연 흉골 봉합 은 혈역학적으로 불안정한 심장을 감압하는 좋은 방법이며 성공적인 결과를 얻기 위해서는 적응증에 대한 신중한 고려가 선행되어야 한다고 생각된다.

  • PDF

Robust Backup Path Selection in Overlay Routing with Bloom Filters

  • Zhou, Xiaolei;Guo, Deke;Chen, Tao;Luo, Xueshan
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • 제7권8호
    • /
    • pp.1890-1910
    • /
    • 2013
  • Routing overlay offers an ideal methodology to improve the end-to-end communication performance by deriving a backup path for any node pair. This paper focuses on a challenging issue of selecting a proper backup path to bypass the failures on the default path with high probability for any node pair. For existing backup path selection approaches, our trace-driven evaluation results demonstrate that the backup and default paths for any node pair overlap with high probability and hence usually fail simultaneously. Consequently, such approaches fail to derive a robust backup path that can take over in the presence of failure on the default path. In this paper, we propose a three-phase RBPS approach to identify a proper and robust backup path. It utilizes the traceroute probing approach to obtain the fine-grained topology information, and systematically employs the grid quorum system and the Bloom filter to reduce the resulting communication overhead. Two criteria, delay and fault-tolerant ability on average, of the backup path are proposed to evaluate the performance of our RBPS approach. Extensive trace-driven evaluations show that the fault-tolerant ability of the backup path can be improved by about 60%, while the delay gain ratio concentrated at 14% after replacing existing approaches with ours. Consequently, our approach can derive a more robust and available backup path for any node pair than existing approaches. This is more important than finding a backup path with the lowest delay compared to the default path for any node pair.

우심실유출로협착증의 수술예후에 영향을 미치는 인자에 관한 연구 (A Study about Factors Influencing on the Postoperative Prognosis of the Right Ventricular Outflow Trac Obstruction)

  • 최강주
    • Journal of Chest Surgery
    • /
    • 제27권6호
    • /
    • pp.435-443
    • /
    • 1994
  • Surgical procedures to relieve congenital right ventricular outflow tract[RVOT] obstruction of heart were performed on 125 patients from September 1985 to August 1992. There were 65 males and 60 females. Ages ranged from 7 months to 33 years with a mean age of 8 years. All the patients were divided into three main groups[I, II, III] depending on the presence or absence of cyanosis and combined anomalies. The patient were classified into two groups; A and B according to the outcome after surgical repair. Group A included the patients who had a good postoperative outcome with or without mild complications such as wound disruption, or hydrothorax. Group B included the patients who had a poor outcome including hospital death and significant postoperative complications such as heart failure, low output syndrome, respiratory failure, hepatic failure and others. And the results were summarized as follows. 1. There were no significant differences in age, body surface area and aortic dimension among the group I, II, and III, but there were significant differences among groups in pulmonary arterial dimension, ACT[aortic cross clamping time], TBT [total bypass time], preoperative and postoperative ratio of systolic pressure of right and left ventricles [pre PRV/RV and post PRV/LV], and the size of Hegar dilator which passed through the RVOT postoperatively [p<0.05]. 2. In the group A and B, there were significant differences in pulmonary arterial dimension [group A:1.6$\pm$0.5 cm, group B:1.9$\pm$0.6 cm], ACT [group A:102.3$\pm$ 46.0 minute, group B:76.1$\pm$46.1 minute], TBT [group A:133.9$\pm$56.6 minute, group B:94.9$\pm$51.9 minute], pre PRV/LV [group A:1.06$\pm$0.24, group B:0.8$\pm$0.32], post PRV/LV [group A:0.58$\pm$0.18, group B:0.43$\pm$0.16].It has been concluded that postoperative prognosis of RVOT obstruction was influenced by pulmonary arterial dimension, ACT, TBT, severity of RVOT obstruction [pre PRV/LV] and post PRV/LV.

  • PDF

Serum Copeptin Levels Predict Clinical Outcomes After Successful Percutaneous Coronary Intervention in Patients With Acute Myocardial Infarction

  • Choi, Hyun-Jung;Kim, Min Chul;Sim, Doo Sun;Hong, Young Joon;Kim, Ju Han;Jeong, Myung Ho;Kim, Soo-Hyun;Shin, Myung-Geun;Ahn, Youngkeun
    • Annals of Laboratory Medicine
    • /
    • 제38권6호
    • /
    • pp.538-544
    • /
    • 2018
  • Background: Serum copeptin has been demonstrated to be useful in early risk stratification and prognostication of patients with acute myocardial infarction (AMI). However, the prognostic value of copeptin after percutaneous coronary intervention (PCI) for clinical outcomes remains uncertain. We investigated the prognostic role of serum copeptin levels immediately after successful PCI as a prognostic marker for major adverse cardiac events (MACE; comprising death, repeat PCI, recurrent MI, or coronary artery bypass grafting) in patients with AMI. Methods: A retrospective study was performed in 149 patients with AMI who successfully received PCI. Serum copeptin levels were analyzed in blood samples collected immediately after PCI. The association between copeptin levels and MACE during the follow-up period was evaluated. Results: MACE occurred in 34 (22.8%) patients during a median follow-up of 30.1 months. MACE patients had higher copeptin levels than non-MACE patients did. Multiple logistic regression analysis showed that the increase in serum copeptin levels was associated with increased MACE incidence (odds ratio=1.6, P =0.005). Conclusions: A high level of serum copeptin measured immediately after PCI was associated with MACE in patients with AMI during long-term follow-up. Serum copeptin levels can serve as a prognostic marker in patients with AMI after successful PCI.

낙동강 유역 내 하수처리구역의 비점오염원 부하량에 대한 비점저감 기여율 분석 (Nonpoint Removal Contribution Ratio Analysis of Nonpoint Source Pollutants Loads from Sewage Treatment Area in Watershed of Nakdong River)

  • 장종경;김미은;김재문;장영수;신현석
    • 한국수자원학회:학술대회논문집
    • /
    • 한국수자원학회 2015년도 학술발표회
    • /
    • pp.445-445
    • /
    • 2015
  • 비점오염의 특성에 대해 지속적으로 연구 중이지만 수문특성과 연관성이 크다 보니 그 일관성에 대해 확실한 기법이 개발되지 않았다. 기법 개발과 효과적인 오염원 관리를 위해 SWMM 등의 모형을 활용하고 있지만 투입된 노력과 시간에 비해 그 효율성이 매우 적은 편이다. 이런 부분을 보완하고자 본 논문에서는 기존의 비점오염량 산정방법이 아니라 낙동강유역의 도시화 특성 및 수문/기상자료와 처리장 운영자료를 활용한 차별화된 원단위법을 통해 비점 배출 부하량 산정방법을 제시하려고 한다. 배수구역 내 관거 시스템을 합류식으로 가정하였고 배수구역별 비점 발생형태는 하수처리장의 강우 유입량, 하수처리장의 우회유량(Bypass 유량), 하수처리구역의 CSO 유량 3가지로 구분 지었다. 유입 방류자료와 강우자료를 활용하여 임계강우량을 3mm로 설정하여 3mm이상일 경우에 우회유량이 발생한다고 가정하였고 우회유량 발생시 오염부하량 산정은 건기평균유량에 유량변동부하율을 곱하여 시간최대유량으로 전환한 후 강우 지속기간 동안만 우회유량이 발생하는 것으로 가정하였다. CSO 유량은 처리구역/배수구역 면적비에 따라 3개의 그룹으로 구분한 뒤 검증된 SWMM-온천천 모형의 각 소유역별 불투수면적비와 비교하여 유사한 소유역을 각 그룹의 대표유역으로 선정하였다. 선정된 소유역의 CSO 유량과 수문현상의 비선형적인 관계를 고려할 수 있는 신경망 기법을 적용하여 강우특성에 따른 CSO 오염부하량 산정을 실시하였다. 산정결과를 바탕으로 각 하수처리장별 비점저감 기여율을 산정한 결과 대구북부 처리장에서 21.56%로 가장 높은 효율을 보여줬으며 거창가조 지점에서 0.11%로 가장 낮은 효율을 보여주는 것을 확인 할 수 있었다. 이러한 결과를 바탕으로 낙동강유역 내 위치한 하수처리장의 효율성에 대해 알 수 있으며 개선되어야 할 처리장들을 알 수 있었다. 또한 획일화된 방법이 아닌 차별화된 원단위법을 통한 오염부하량 산정은 앞으로의 연구방향에 있어서 좋은 사례가 될 것으로 사료된다.

  • PDF

The Fate of Partially Thrombosed Intracranial Aneurysms Treated with Endovascular Intervention

  • Lee, Jeongjun;Cho, Won-Sang;Yoo, Roh Eul;Yoo, Dong Hyun;Cho, Young Dae;Kang, Hyun-Seung;Kim, Jeong Eun
    • Journal of Korean Neurosurgical Society
    • /
    • 제64권3호
    • /
    • pp.427-436
    • /
    • 2021
  • Objective : The fate of partially thrombosed intracranial aneurysms (PTIAs) is not well known after endovascular treatment. The authors aimed to analyze the treatment outcomes of PTIAs. Methods : We retrospectively reviewed the medical records of 27 PTIAs treated with endovascular intervention between January 1999 and March 2018. Twenty-one aneurysms were treated with intraluminal embolization (ILE), and six were treated with parent artery occlusion (PAO) with or without bypass surgery. Radiological results, clinical outcomes and risk factors for major recurrence were assessed. Results : The initial clinical status was similar in both groups; however, the last status was better in the ILE group than in the PAO group (p=0.049). Neurological deterioration resulted from mass effect in one case and rupture in one after ILE, and mass effect in two and perforator infarction in one after PAO. Twenty cases (94.2%) in the ILE group initially achieved complete occlusion or residual neck status. However, 13 cases (61.9%) showed major recurrence, the major causes of which included coil migration or compaction. Seven cases (33.3%) ultimately achieved residual sac status after repeat treatment. In the PAO group, all initially showed complete occlusion or a residual neck, and just one case ultimately had a residual sac. Two cases showed major recurrence, the cause of which was incomplete PAO. Aneurysm wall calcification was the only significantly protective factor against major recurrence (odds ratio, 36.12; 95% confidence interval, 1.85 to 705.18; p=0.018). Conclusion : Complete PAO of PTIAs is the best option if treatment-related complications can be minimized. Simple fluoroscopy is a useful imaging modality because of the recurrence pattern.

중소기업의 신규상장과 정보비대칭 (IPO of SMEs and Information Asymmetry)

  • 김주환;박진우
    • 아태비즈니스연구
    • /
    • 제11권2호
    • /
    • pp.173-188
    • /
    • 2020
  • Purpose - This study examines the determinants of offer price and short-term and long-term performance of small and medium-sized enterprise(SME) IPO stocks listed on the KOSDAQ during the period from July 2007 to December 2016. Design/methodology/approach - The SME IPO samples are classified into three categories of regular listing, technology-based special listing, and listing by merger with special purpose acquisition company(SPAC), whose results are compared each other and compared to the result for the KOSDAQ listing of large firms. Findings - From the point of SME management which attempts to list its company on the KOSDAQ, the listing by merger with SPAC is the most unfavorable, and the underpricing phenomenon of the technology-based special listing is severe in the second place. By contrast, IPO stock investors can earn the largest abnormal return by purchasing the SPAC which succeeds the merger with unlisted firm, and the next abnormal returns are obtained in the order of the IPO stocks of technology-based special listing, regular listing of SMEs, and regular listing of large firms. However, it is interesting to observe that the net buying ratio of individual investors is relatively large for the IPO stocks of regular listing of SMEs and large firms, which exhibit the long-term under-performance. Research implications or Originality - This result implies that the exceptional listing system such as the technology-based special listing or the listing by merger with SPAC cost the SMEs which bypass the complicated procedure of the regular listing.

Minimally Invasive Procedure versus Conventional Redo Sternotomy for Mitral Valve Surgery in Patients with Previous Cardiac Surgery: A Systematic Review and Meta-Analysis

  • Muhammad Ali Tariq;Minhail Khalid Malik;Qazi Shurjeel Uddin;Zahabia Altaf;Mariam Zafar
    • Journal of Chest Surgery
    • /
    • 제56권6호
    • /
    • pp.374-386
    • /
    • 2023
  • Background: The heightened morbidity and mortality associated with repeat cardiac surgery are well documented. Redo median sternotomy (MS) and minimally invasive valve surgery are options for patients with prior cardiac surgery who require mitral valve surgery (MVS). We conducted a systematic review and meta-analysis comparing the outcomes of redo MS and minimally invasive MVS (MIMVS) in this population. Methods: We searched PubMed, EMBASE, and Scopus for studies comparing outcomes of redo MS and MIMVS for MVS. To calculate risk ratios (RRs) for binary outcomes and weighted mean differences (MDs) for continuous data, we employed a random-effects model. Results: We included 12 retrospective observational studies, comprising 4157 participants (675 for MIMVS; 3482 for redo MS). Reductions in mortality (RR, 0.54; 95% confidence interval [CI], 0.37-0.80), length of hospital stay (MD, -4.23; 95% CI, -5.77 to -2.68), length of intensive care unit (ICU) stay (MD, -2.02; 95% CI, -3.17 to -0.88), and new-onset acute kidney injury (AKI) risk (odds ratio, 0.34; 95% CI, 0.19 to 0.61) were statistically significant and favored MIMVS (p<0.05). No significant differences were observed in aortic cross-clamp time, cardiopulmonary bypass time, or risk of perioperative stroke, new-onset atrial fibrillation, surgical site infection, or reoperation for bleeding (p>0.05). Conclusion: The current literature, which primarily consists of retrospective comparisons, underscores certain benefits of MIMVS over redo MS. These include decreased mortality, shorter hospital and ICU stays, and reduced AKI risk. Given the lack of high-quality evidence, prospective randomized control trials with adequate power are necessary to investigate long-term outcomes.