• Title/Summary/Keyword: Patent strategy

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An Analysis of Industry-University-Institute R&D Collaboration and Firm Performance on SMEs (중소기업의 산학연 연구개발(R&D) 협력과 기업 성과 분석)

  • Chung, Do-Bum;Ko, Yun-Mi;Kim, Kyung-Nam
    • Journal of Technology Innovation
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    • v.20 no.1
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    • pp.115-140
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    • 2012
  • From a point of knowledge based view, IUI(Industry-University-Institute) R&D collaboration is recognized as an important way to acquire lacking technology and knowledge. In this study, we investigated firm performance of IUI R&D collaboration on national R&D project. That is, we identified whether a collaborative research really affects firm performance, and whether firm performance is differed by types of collaboration. To test our hypotheses, we selected 250 Korean SMEs(Small and Medium Enterprises) which were funded from government R&D for 2006-2009, and we verified relations between the ratio and/or types of R&D collaboration and firm performance. Firm performance was measured by number of patent applied and ROA(Return on Assets) after completion of the project (in year t+1). Findings showed that the relationship between the ratio of R&D collaboration and technological performance was inverted U-shape. Among types of R&D collaboration, though inter-industry collaborative research was negatively related to technological performance, IUI collaborative research was positively related to technological performance. However, the ratio and types of R&D collaboration had no relation to economic performance. The results of this study will contribute to the strategy of SMEs as well as the policy of a government with regard to IUI R&D collaboration.

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Classification of Environmental Industry and Technology Competitiveness Evaluation (환경산업기술 분류체계 및 기술 경쟁력 평가)

  • Han, Daegun;Bae, Young Hye;Kim, Tae-Yong;Jung, Jaewon;Lee, Choongke;Kim, Hung Soo
    • Journal of Wetlands Research
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    • v.22 no.4
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    • pp.245-256
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    • 2020
  • The purpose of this study is to evaluate the technological competitiveness of the environmental industry with developed countries in order to establish an international market expansion strategy of the Korean environmental industry and technology. In order to evaluate the competitiveness of the environmental industry and technology, core technologies were classified by the environmental industry sectors based on the classification system of the domestic and international environmental industry and technology. After developing the evaluation index data, the Delphi analysis, journal and patent analysis, as well as the export and import analysis were carried out and the standardization analysis was performed on the index data. Moreover, the weights of each evaluation index were calculated using the AHP(Analytic Hierarchy Process) method and the evaluation results of competitiveness of the environmental industry and technology in Korea, the United States, the United Kingdom, Germany, and France were derived. As a result of the evaluation, the United States was rated with the highest technological competitiveness in all the environmental industry sectors, while Korea got the lowest technological competitiveness rating compared to the 4 developed countries. In particular, Korea got the lowest level of technological competitiveness in the sector of multi-media environmental management and development for a sustainable social system. Therefore, in order for the Korean environmental industry and technology to enter the global advanced market, it is necessary to strengthen the competitiveness through the development of the fourth environmental industry based on IoT(Internet of Things), cloud, big data, mobile, and AI(Artificial Intelligence), which are currently the country's domestic strengths.

An Analysis of the Linked Structure for Technology-Industry in National R&D Projects (국가 R&D과제의 기술-산업 연계구조분석)

  • Lee, Mi-Jeong;Lee, June-Young;Kim, Do-Hyun;Shim, We;Jeong, Dae-Hyun;Kim, Kang-Hoe;Kwon, Oh-Jin;Moon, Yeong-Ho
    • Journal of Korea Technology Innovation Society
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    • v.15 no.2
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    • pp.443-460
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    • 2012
  • Technology is closely related to industrial development and various studies have been performed to understand the linked structure for knowledge flow between the technology and industry. The research, however, wasn't carried out to flow for Korea National Research and Development projects. In this study, linked structure for technology-industry was discussed by utilizing patent data performed in actual National R&D using NTIS Information of the national research and development, and then it was analyzed how knowledge flows between the technology and industry are flowing. It should be defined that the individual applications expected by researchers at the start of the research and technology-industry applications actually applied from the research performances after research was completed. As a result, it was confirmed in most projects the flow of knowledge was occurring to predicted industries before the start of the R&D. However, the technology was applied to unexpected industry in three industries such as Y09(medical, precision and optical instruments), Y10(electrical and mechanical equipment), Y11(automotive and transportation equipment). The results of this study will be able to contribute to planning for efficient investment strategy of technology-industry by investigating the technology-industry knowledge flow relations of national R&D projects.

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Slit Ventricle Syndrome in Children : Clinical Presentation and Treatment (소아에서 틈새뇌실 증후군 : 임상 양상 및 치료)

  • Shin, Beom-Sik;Yang, Kook-Hee;Kim, Dong-Seok;Choi, Joong-Uhn
    • Journal of Korean Neurosurgical Society
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    • v.30 no.sup2
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    • pp.309-315
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    • 2001
  • The term slit ventricle syndrome(SVS) refers to an episodic occurrence of headache, vomiting, and possibly some degree of impaired consciousness in shunted hydrocephalic children in whom slit-like ventricles are seen on CT scan or MRI. Authors present 6 cases with SVS who were treated at our institute for last 10 years. From 1986 to 1996, 821 patients underwent shunt surgery for hydrocephalus. The etiology of hydrocephalus included brain tumor(140 patients), post-hemorrhagic(62 patients), idiopathic normotensive hydrocephalus(64 patients), post-meningitic( 58 patients), post-traumatic(54 patients), congenital(48 patients), neurocysticercosis(31 patients), and unknown etiology(364 patients). During the mean follow-up duration of 68 months, 232 shunt revisions were performed by a revision rate of 1.28 per patient. The incidence of SVS was 0.7%(6 patients). Most of them have been operated on in infancy. Time interval from the first operation to the development of slit-ventricle syndrome ranged from 4 to 8 years, the mean was 6 years. Shuntogram showed patent shunt in all patients. Two patients with less severe clinical symptoms improved with conservative treatment. These patients were not measured ICP because of good hospital course. One patient showed high ICP and needed only revision with same pressure valve as previous shunt. Low ICP was noted in 3 patients. Pressure augmentation using an anti-siphon device(ASD) or upgrading valve system were necessary in these patients. The authors stress that determining type of SVS is the first step in treatment planning and that the best treatment is a strategy aimed at resolving the specific type of SVS responsible for the symptoms.

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Research Framework for International Franchising (국제프랜차이징 연구요소 및 연구방향)

  • Kim, Ju-Young;Lim, Young-Kyun;Shim, Jae-Duck
    • Journal of Global Scholars of Marketing Science
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    • v.18 no.4
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    • pp.61-118
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    • 2008
  • The purpose of this research is to construct research framework for international franchising based on existing literature and to identify research components in the framework. Franchise can be defined as management styles that allow franchisee use various management assets of franchisor in order to make or sell product or service. It can be divided into product distribution franchise that is designed to sell products and business format franchise that is designed for running it as business whatever its form is. International franchising can be defined as a way of internationalization of franchisor to foreign country by providing its business format or package to franchisee of host country. International franchising is growing fast for last four decades but academic research on this is quite limited. Especially in Korea, research about international franchising is carried out on by case study format with single case or empirical study format with survey based on domestic franchise theory. Therefore, this paper tries to review existing literature on international franchising research, providing research framework, and then stimulating new research on this field. International franchising research components include motives and environmental factors for decision of expanding to international franchising, entrance modes and development plan for international franchising, contracts and management strategy of international franchising, and various performance measures from different perspectives. First, motives of international franchising are fee collection from franchisee. Also it provides easier way to expanding to foreign country. The other motives including increase total sales volume, occupying better strategic position, getting quality resources, and improving efficiency. Environmental factors that facilitating international franchising encompasses economic condition, trend, and legal or political factors in host and/or home countries. In addition, control power and risk management capability of franchisor plays critical role in successful franchising contract. Final decision to enter foreign country via franchising is determined by numerous factors like history, size, growth, competitiveness, management system, bonding capability, industry characteristics of franchisor. After deciding to enter into foreign country, franchisor needs to set entrance modes of international franchising. Within contractual mode, there are master franchising and area developing franchising, licensing, direct franchising, and joint venture. Theories about entrance mode selection contain concepts of efficiency, knowledge-based approach, competence-based approach, agent theory, and governance cost. The next step after entrance decision is operation strategy. Operation strategy starts with selecting a target city and a target country for franchising. In order to finding, screening targets, franchisor needs to collect information about candidates. Critical information includes brand patent, commercial laws, regulations, market conditions, country risk, and industry analysis. After selecting a target city in target country, franchisor needs to select franchisee, in other word, partner. The first important criteria for selecting partners are financial credibility and capability, possession of real estate. And cultural similarity and knowledge about franchisor and/or home country are also recognized as critical criteria. The most important element in operating strategy is legal document between franchisor and franchisee with home and host countries. Terms and conditions in legal documents give objective information about characteristics of franchising agreement for academic research. Legal documents have definitions of terminology, territory and exclusivity, agreement of term, initial fee, continuing fees, clearing currency, and rights about sub-franchising. Also, legal documents could have terms about softer elements like training program and operation manual. And harder elements like law competent court and terms of expiration. Next element in operating strategy is about product and service. Especially for business format franchising, product/service deliverable, benefit communicators, system identifiers (architectural features), and format facilitators are listed for product/service strategic elements. Another important decision on product/service is standardization vs. customization. The rationale behind standardization is cost reduction, efficiency, consistency, image congruence, brand awareness, and competitiveness on price. Also standardization enables large scale R&D and innovative change in management style. Another element in operating strategy is control management. The simple way to control franchise contract is relying on legal terms, contractual control system. There are other control systems, administrative control system and ethical control system. Contractual control system is a coercive source of power, but franchisor usually doesn't want to use legal power since it doesn't help to build up positive relationship. Instead, self-regulation is widely used. Administrative control system uses control mechanism from ordinary work relationship. Its main component is supporting activities to franchisee and communication method. For example, franchisor provides advertising, training, manual, and delivery, then franchisee follows franchisor's direction. Another component is building franchisor's brand power. The last research element is performance factor of international franchising. Performance elements can be divided into franchisor's performance and franchisee's performance. The conceptual performance measures of franchisor are simple but not easy to obtain objectively. They are profit, sale, cost, experience, and brand power. The performance measures of franchisee are mostly about benefits of host country. They contain small business development, promotion of employment, introduction of new business model, and level up technology status. There are indirect benefits, like increase of tax, refinement of corporate citizenship, regional economic clustering, and improvement of international balance. In addition to those, host country gets socio-cultural change other than economic effects. It includes demographic change, social trend, customer value change, social communication, and social globalization. Sometimes it is called as westernization or McDonaldization of society. In addition, the paper reviews on theories that have been frequently applied to international franchising research, such as agent theory, resource-based view, transaction cost theory, organizational learning theory, and international expansion theories. Resource based theory is used in strategic decision based on resources, like decision about entrance and cooperation depending on resources of franchisee and franchisor. Transaction cost theory can be applied in determination of mutual trust or satisfaction of franchising players. Agent theory tries to explain strategic decision for reducing problem caused by utilizing agent, for example research on control system in franchising agreements. Organizational Learning theory is relatively new in franchising research. It assumes organization tries to maximize performance and learning of organization. In addition, Internalization theory advocates strategic decision of direct investment for removing inefficiency of market transaction and is applied in research on terms of contract. And oligopolistic competition theory is used to explain various entry modes for international expansion. Competency theory support strategic decision of utilizing key competitive advantage. Furthermore, research methodologies including qualitative and quantitative methodologies are suggested for more rigorous international franchising research. Quantitative research needs more real data other than survey data which is usually respondent's judgment. In order to verify theory more rigorously, research based on real data is essential. However, real quantitative data is quite hard to get. The qualitative research other than single case study is also highly recommended. Since international franchising has limited number of applications, scientific research based on grounded theory and ethnography study can be used. Scientific case study is differentiated with single case study on its data collection method and analysis method. The key concept is triangulation in measurement, logical coding and comparison. Finally, it provides overall research direction for international franchising after summarizing research trend in Korea. International franchising research in Korea has two different types, one is for studying Korean franchisor going overseas and the other is for Korean franchisee of foreign franchisor. Among research on Korean franchisor, two common patterns are observed. First of all, they usually deal with success story of one franchisor. The other common pattern is that they focus on same industry and country. Therefore, international franchise research needs to extend their focus to broader subjects with scientific research methodology as well as development of new theory.

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Hybrid Off-pump Coronary Artery Bypass Combined with Percutaneous Coronary Intervention: Indications and Early Results (심폐바이패스 없이 시행하는 관상동맥우회술과 경피적 관상동맥중재술의 병합요법 : 적응증 및 조기성적)

  • Hwang Ho Young;Kim Jin Hyun;Cho Kwang Ree;Kim Ki-Bong
    • Journal of Chest Surgery
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    • v.38 no.11 s.256
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    • pp.733-738
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    • 2005
  • Background: The possibility of incomplete revascularization and development of flow competition after revascularization of the borderline lesion made the hybrid strategy as an option for complete revascularization. Material and Method: From January f998 to July 2004, 25 $(3.2\%)$ patients underwent hybrid revascularization among 782 total OPCAB procedures. Clinical results and angiographic patencies were evalulated. Percutaneous coronary intervention (PCI) was peformed before CABG in 8 patients and after CABG in 47 patients. Result: The causes of PCIs before CABG were to achieve complete revascularization with minimally invasive surgery (n=7) and emergent PCI for culprit lesion (n=1). The indications of PCIs after CABG were high possibility of flow competition in the borderline lesion of right coronary artery territory (n=8), diffuse atheromatous lesion preventing anastomosis of graft (n=5), severe calcified ascending aorta with no more arterial grafi available (n=3), and intramyocardial coronary lesion (n=1). Mean number of distal anastomoses was $2.3\pm1.0$. Mean number of lesions treated by PCI was $1.2\pm0.4$. There was no operative or procedure-related mortality. PCI-related complication was periprocedural myocardial infarction in one patient, and complications related to CABG were transient atrial fibrillation (n=5), perioperative myocardial infarction (n=1), and transient renal dysfunction (n=1). Early postoperative coronary angiography $(1.8{pm}1.6days)$ revealed $100\%$ patency rate of grafts (57/57). The stenosis occurred in one patient performed PCI before CABG, which was successfully treated with re-ballooning. During midterm follow-up (mean; $25{\pm}26$ months), 1 patient died of congestive heart failure. All survivors (n=24) accomplished follow-up coronary angiographics, which showed .all grafts (56/57) were patent except one string sign. In-stent restenosis was developed in 2 patients who received bare metal stents. Conclusion: In selected patients, complete revascularization was achieved with low risk by taking the hybrid strategy.

A Study on Intelligent Value Chain Network System based on Firms' Information (기업정보 기반 지능형 밸류체인 네트워크 시스템에 관한 연구)

  • Sung, Tae-Eung;Kim, Kang-Hoe;Moon, Young-Su;Lee, Ho-Shin
    • Journal of Intelligence and Information Systems
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    • v.24 no.3
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    • pp.67-88
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    • 2018
  • Until recently, as we recognize the significance of sustainable growth and competitiveness of small-and-medium sized enterprises (SMEs), governmental support for tangible resources such as R&D, manpower, funds, etc. has been mainly provided. However, it is also true that the inefficiency of support systems such as underestimated or redundant support has been raised because there exist conflicting policies in terms of appropriateness, effectiveness and efficiency of business support. From the perspective of the government or a company, we believe that due to limited resources of SMEs technology development and capacity enhancement through collaboration with external sources is the basis for creating competitive advantage for companies, and also emphasize value creation activities for it. This is why value chain network analysis is necessary in order to analyze inter-company deal relationships from a series of value chains and visualize results through establishing knowledge ecosystems at the corporate level. There exist Technology Opportunity Discovery (TOD) system that provides information on relevant products or technology status of companies with patents through retrievals over patent, product, or company name, CRETOP and KISLINE which both allow to view company (financial) information and credit information, but there exists no online system that provides a list of similar (competitive) companies based on the analysis of value chain network or information on potential clients or demanders that can have business deals in future. Therefore, we focus on the "Value Chain Network System (VCNS)", a support partner for planning the corporate business strategy developed and managed by KISTI, and investigate the types of embedded network-based analysis modules, databases (D/Bs) to support them, and how to utilize the system efficiently. Further we explore the function of network visualization in intelligent value chain analysis system which becomes the core information to understand industrial structure ystem and to develop a company's new product development. In order for a company to have the competitive superiority over other companies, it is necessary to identify who are the competitors with patents or products currently being produced, and searching for similar companies or competitors by each type of industry is the key to securing competitiveness in the commercialization of the target company. In addition, transaction information, which becomes business activity between companies, plays an important role in providing information regarding potential customers when both parties enter similar fields together. Identifying a competitor at the enterprise or industry level by using a network map based on such inter-company sales information can be implemented as a core module of value chain analysis. The Value Chain Network System (VCNS) combines the concepts of value chain and industrial structure analysis with corporate information simply collected to date, so that it can grasp not only the market competition situation of individual companies but also the value chain relationship of a specific industry. Especially, it can be useful as an information analysis tool at the corporate level such as identification of industry structure, identification of competitor trends, analysis of competitors, locating suppliers (sellers) and demanders (buyers), industry trends by item, finding promising items, finding new entrants, finding core companies and items by value chain, and recognizing the patents with corresponding companies, etc. In addition, based on the objectivity and reliability of the analysis results from transaction deals information and financial data, it is expected that value chain network system will be utilized for various purposes such as information support for business evaluation, R&D decision support and mid-term or short-term demand forecasting, in particular to more than 15,000 member companies in Korea, employees in R&D service sectors government-funded research institutes and public organizations. In order to strengthen business competitiveness of companies, technology, patent and market information have been provided so far mainly by government agencies and private research-and-development service companies. This service has been presented in frames of patent analysis (mainly for rating, quantitative analysis) or market analysis (for market prediction and demand forecasting based on market reports). However, there was a limitation to solving the lack of information, which is one of the difficulties that firms in Korea often face in the stage of commercialization. In particular, it is much more difficult to obtain information about competitors and potential candidates. In this study, the real-time value chain analysis and visualization service module based on the proposed network map and the data in hands is compared with the expected market share, estimated sales volume, contact information (which implies potential suppliers for raw material / parts, and potential demanders for complete products / modules). In future research, we intend to carry out the in-depth research for further investigating the indices of competitive factors through participation of research subjects and newly developing competitive indices for competitors or substitute items, and to additively promoting with data mining techniques and algorithms for improving the performance of VCNS.

An Exploratory Study on Customers' Individual Factors on Waiting Experience (고객의 개인적 요소가 대기시간 경험에 미치는 영향에 대한 탐색적 연구)

  • Kim, Juyoung;Yoo, Bomi
    • Asia Marketing Journal
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    • v.12 no.1
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    • pp.1-30
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    • 2010
  • Customers often experience waiting for buying service. Managing customers' waiting time is important for service providers since customers who are dissatisfied with waiting, secede from a service place at last. Not a few studies have been done to solve waiting time problem and improve customers' waiting experience. Hui & Tse(1996) identify evaluation factors in customers' behavioral mechanism as customers wait. That is, customers experience perceived waiting time, waiting acceptability and emotional response to the wait when they wait. Since customers evaluate the wait using these factors, service provider should manage these factors in order to minimize customers' dissatisfaction. Therefore, this study explores that evaluation factors of waiting are influenced by customers' situational and experiential characteristics, which include customer loyalty, transaction importance for customer and waiting expectation level. Those situational and experiential characteristics are usually given to service providers so they can't control these at waiting point. The major findings derived from two exploratory studies can be summarized as follows. First, according to the result from the study 1 (restaurant setting), customers' transaction importance has the greatest positive influence on waiting experience. The results show restaurant service provider could prevent customers' separation effectively through strategies which raise customers' transaction importance, like giving special coupons for important events. Second, in study 2 (amusement part setting) customer loyalty has large positive impact on waiting experience as well as transaction importance. This results show that service provider could minimize customers' dissatisfaction using strategies which raise customer loyalty continuously. This results show customer perceives waiting experience differently according to characteristics of service place and service itself. Therefore, service provider should grasp the unique customers' situational and experiential characters for each service and service place. It could provide an effective strategy for waiting time management. Third, the study finds transaction importance and waiting expectation level have direct influence customers' waiting experience as independent variables, while existing studies treated them as moderators. Customer loyalty which has not been incorporated in previous waiting time research is known to affect waiting experience. It suggests that marketing strategy which builds up customer loyalty for long period of time is also quite effective, compared to short term tactics to help customers endure waiting time. Fourth, this study reveals the importance of actual waiting time along with perceived waiting time. So far most studies only focus on customers' perceived waiting time. Especially, this study incorporates the concept of patient limit on waiting time to investigate effect of actual waiting time. The results show that there were various responses to the wait depending on how actual waiting time exceeds individual's patent limit on waiting time or not, even though customers wait about the same period of time. Finally, using structural equation model, conceptual path between behavioral responses is verified. As customer perceives waiting time, then she decides whether she can endure it or not, and then her emotional response occurs. This result are somewhat different from Hui & Tse(1996)'s study. The study also includes theoretical contributions as well as practical implications.

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Outcome of Staged Repair of Tetralogy of Fallot with Pulmonary Atresia and a Ductus-dependent Pulmonary Circulation: Should Primary Repair Be Considered?

  • Kim, Hyung-Tae;Sung, Si-Chan;Chang, Yun-Hee;Jung, Won-Kil;Lee, Hyoung-Doo;Park, Ji-Ae;Huh, Up
    • Journal of Chest Surgery
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    • v.44 no.6
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    • pp.392-398
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    • 2011
  • Background: The tetralogy of Fallot (TOF) with pulmonary atresia (PA) and a ductus-dependent pulmonary circulation (no major aorto-pulmonary collateral arteries (MAPCAs)) has been treated with staged repair or primary repair depending on the preference of surgeons or institutions. We evaluated the 19-year outcome of staged repair for this anomaly to find out whether our surgical strategy should be changed. Materials and Methods: Forty-four patients with TOF/PA with patent ductus arteriosus (PDA) who underwent staged repair from June 1991 to October 2010 were included in this retrospective study. The patients with MAPCAs were excluded. The average age at the first palliative shunt surgery was $40.8{\pm}67.5$ days (range: 0~332 days). Thirty-one patients (31/44, 70%) were neonates. The average weight was $3.5{\pm}1.6$ kg (range: 1.6~8.7 kg). A modified Blalock-Taussig (BT) shunt was performed in 38 patients, classic BT shunt in 4 patients, and central shunt in 2 patients. Six patients required concomitant procedures: pulmonary artery angioplasty was performed in 4 patients, pulmonary artery reconstruction in one patient, and re-implantation of the left pulmonary artery to the main pulmonary artery in one patient. Four patients required a second shunt operation before the definitive repair was performed. Thirty-three patients underwent definitive repair at $24.2{\pm}13.3$ months (range: 7.3~68 months) after the first palliative operation. The average age at the time of definitive repair was $25.4{\pm}13.5$ months (range: 7.6~68.6 months) and their average weight was $11.0{\pm}2.1$ kg. For definitive repair, 3 types of right ventricular outflow procedures were used: extra-cardiac conduit was performed in 30 patients, trans-annular patch in 2 patients, and REV operation in 1 patient. One patient was lost to follow-up after hospital discharge. The mean follow-up duration for the rest of the patients was $72{\pm}37$ months (range: 4~160 months). Results: Ten patients (10/44, 22.7%) died before the definitive repair was performed. Four of them died during hospitalization after the shunt operation. Six deaths were thought to be shunt-related. The average time of shunt-related deaths after shunt procedures was 8.7 months (range: 2 days~25.3 months). There was no operative mortality after the definitive repair, but one patient died from dilated cardiomyopathy caused by myocarditis 8 years and 3 months after the definitive repair. Five-year and 10-year survival rates after the first palliative operation were 76.8% and 69.1%, respectively. Conclusion: There was a high overall mortality rate in staged repair for the patients with TOF/PA with PDA. Majority of deaths occurred before the definitive repair was performed. Therefore, primary repair or early second stage definitive repair should be considered to enhance the survival rate for patients with TOF/PA with PDA.

Coronary Angiography after Coronary artery Bypass Grafting (관상동맥 우회술후 관상동맥 조영검사 소견)

  • Choi, Jin-Ho;Park, Kay-Hyun;Jun, Tae-Gook;Lee, Young-Tak;Park, Pyo-Won;Chae, Hurn;Lee, Jong-Tae
    • Journal of Chest Surgery
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    • v.35 no.3
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    • pp.182-187
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    • 2002
  • Background: There have been many reports of coronary angiographic findings after coronary bypass grafting, most of which are focused on the graft patency rate of the bypass conduits. However, postoperative angiography can provide numerous informations other than patency rates that are useful for establishing operative strategy. Material and Method: We studied 73 patients in whom coronary angiography was done after more than 1 month of CABG. Mean interval from the operation to coronary angiography was 10.6 months and the reasons for coronary angiography follow up were residual or recurrent angina in 54 patients, abnormalities on myocardial perfusion scan or echocardiography in 13 patients, and for simple follow up in 6 patients. Result: Overall graft patency rate was 80.9% (internal thoracic artery 100%, saphenous vein 75.0%) in patients of simple follow up and 61.6%(internal thoracic artery 81.1%, saphenous vein 55.3%) in patients with ischemia. Progression of native coronary arterial disease proximal to the grafting site was found in 50 patients(68.5%). Among 201 coronary arterial branches that had not been completely occluded preoperatively, ninty five branches(47.3%) revealed progression of diameter stenosis by more than 20% on the follow up study. Among them, 64 branches(31.8%) progressed to total occlusion. The incidence of disease progression was highter in the coronary arteries with patent grafts(57.5%) than in those with occluded grafts(36.3%)(p<0.05), Comparing internal thoracic artery graft with saphenous vein graft, internal thoracic artery was superior to saphenous vein, not only in terms of patency(83.3% vs 56.6%), but also in terms of result of later percutaneous intervention success rate(100% vs 62%, p<0.05). Conclusion: Due to the considerable incidence of progression of native coronary artery stenosis in the early postoperative periods, bypass grafting of a vessel with borderline stenosis, especially with vein graft, must be done prudently. And it was confirmed again that revascularization of left anterior descending artery is most important and that internal thoracic artery was superior to saphenous vein.