• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.1495-1496
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• 2011

• Korean Journal of Clinical Pharmacy
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• v.22 no.2
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• pp.113-122
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• 2012

ACC/AHA/SCAI Guideline recommends for administration dual antiplatelet therapy after drug-eluting stent (DES) to prevent restenosis and stent thrombosis in patients with percutaneous coronary intervention (PCI). Recently triple antiplatelet therapy including cilostazol is known to reduce restenosis and stent thrombosis significantly after DES implantation. However, there is lack of data providing the efficacy of triple antiplatelet therapy. The purpose of this study is to evaluate the clinical effects of the triple therapy after DES implantation compared with the dual therapy. This retrospective study collected data from medical charts of 251 patients who received DES implantation between Jul 2006 and Jun 2008. They received either dual antiplatelet therapy (N = 154 clopidogrel and aspirin; Dual group) or triple antiplatelet therapy (N = 97 cliostazol, clopidogrel and aspirin; Triple group). Major adverse cardiac event rates (MACE, included total death, myocardial infarction, target lesion revascularization) at 12 months, 24 months, stent thrombosis, rates of bleeding complications and adverse drug reactions were compared between these two groups. Compared with the dual group, the triple group had a similar incidence of the MACE rates at 24months (12.3% vs. 12.4%, p = 0.99). There is no difference in overall stent thrombosis between two groups (Dual group 2.6% vs. Triple group 4.1%, p = 0.5). Subgroup analysis showed that diabetic patients got more benefit in reducing MACE rates but, there is no statistical difference. Bleeding complications and adverse drug effects were not different significantly. As compared with dual antiplatelet therapy, triple antiplatelet therapy did not reduce the 12-months, 24-months MACE rates and stent thrombosis. Bleeding complications and adverse drug effects were not different.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.29 no.1 s.232
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• pp.156-162
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• 2005

Stouts are frequently used throughout the human body, but the most critical areas are in coronary arteries. They open pathways in vessels and supply blood directly to the heart muscle. To simulate behavior of expansion for the coronary stent by balloon, the commercial finite element code LS-DYNA and ANSYS were used in the analysis. The explicit method is used to analyze the expansion of the stent and the implicit method is performed to simulate the springback that developed in a stent after the balloon pressure has been removed. Finally the experimental results for the expansion of the PS153 stents were compared with the FEM results. The springback was measured with the stents subjected to no external pressure to which stents are subjected in vivo. The simulated results were in good agreement with experimental results. Standard mechanical characteristics such as stress, plastic strains, and springback can be derived from the numerical results. These data can be used to determine maximum expansion diameter without fracture and expansion pressure considering elastic recoil.

• Korean Journal of Optics and Photonics
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• v.26 no.1
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• pp.1-8
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• 2015

The most common cause of a heart attack is known as coronary artery disease, which narrows the arteries and reduces the blood flow to the heart. To treat coronary artery stenosis, percutaneous coronary intervention (PCI) (a nonsurgical procedure to install a stent, which holds the artery wall open) is performed. Intracoronary optical coherence tomography (OCT) is a catheter-based, invasive optical imaging system. To determine whether PCI is appropriate, and to perform stent evaluation in a catheterization laboratory, OCT examinations are carried out. This review details the fundamental principles and technological status of intracoronary OCT imaging, and discusses the ongoing clinical applications to determine the benefits of OCT-guided PCI.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.11
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• pp.2538-2543
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• 2012

The Percutaneous Coronary intervention is a typical way of testing which could be performance to treat a stenosed region by inserting a stent using catheter. In this case, choosing the best stent amongst various kinds of stent for performing an intervention is the most difficult process. For the reason, a width of the blood vessel which is stenosed must be correctly measured to help an operator choose right size of stent. So based on pixel, a width of the blood vessel measured by using the way of Euclidean distance after designing a center-line of vessel from a certain point assigned by operator is shown as a profile in this study. This study would be used as a goof reference for operators when choosing right size of stent.

• The Korean Journal of Nuclear Medicine
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• v.39 no.2
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• pp.87-93
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• 2005

Coronary artery disease (CAD) has been increasing during the last decade and is the one of major causes of death. The management of patients with coronary artery disease has evolved considerably. There are two main strategies in the management of CAD, complementary, not competitive, each other; the pharmacologic therapy to prevent and treat CAD and the percutaneous coronary Intervention (PCI) to restore coronary flow. Antiplatelet drugs and cholesterol lowering drugs have central roles in pharmacotherapy. Drug eluting stent (DES) bring about revolutional changes in PCI. In the management of patients with 57 segment elevation acute myocardial infarction (AMI), there has been a debate on the better strategy for the restoration of coronary flow. Thrombolytic therapy is widely available and easy to administer, whereas primary PCI is less available and more complex, but mote complete. Recently published evidences in the pharmacologic therapy including antiplatelet and stalin, and PCI including DES and reperfusion therapy in patients with ST segment elevation AMI were reviewed.

• Nuclear Medicine and Molecular Imaging
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• v.40 no.2
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• pp.113-119
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• 2006

Coronary artery disease is a loading cause of morbidity and mortality across the world. Percutaneous coronary intervention has become the major technique of revascularization. However, restenosis remains a major limitation of this procedure. Recently the need for repeat intervention due to restenosis, the most vexing long-term failure of percutaneous coronary intervention, has been significantly reduced owing to the introduction of two major advances, intracoronary brachytherapy and the drug-eluting stents. Intracoronary brachytherapy has been employed in recent years to prevent restenosis lesions with effective results, principally in in-stent restenosis. Restenosis is generally considered as au excessive form of normal wound healing divided up in precesses: elastic recoil, neointimal hyperplasia, and negative vascular remodeling. Restenosis has previously been regarded as a proliferative process in which neointimal thickening, mediated by a cascade of inflammatory mediators and other factors, is the key factor. Ionizing radiation has been shown to decrease the proliferative response to injury in animal models of restenosis. Subsequently, several randomized, double blind trials have demonstrated that intracoronary brachytherapy can reduce the rates of both angiographic restenosis and clinical event rates in patients undergoing percutaneous coronary intervention for in stent restenosis. Some problems, such as late thrombosis and edge restenosis, have been identified as limiting factors of this technique. Brachytherapy is a promising method of preventing and treating coronary artery restenosis.

• The Korean Nurse
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• v.30 no.4
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• pp.54-60
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• 1991

• Proceedings of the KSME Conference
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• 2001.06e
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• pp.219-222
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• 2001

The objective of the present study is to evaluate the effects of the stenting shapes on flow velocity and wall shear stress in angulated coronary stenosis by computer simulation. Coronary angiogram and Doppler ultrasound measurement in the patients with angulated coronary stenosis were obtained. Inlet wave velocity distribution obtained from in vivo intracoronary Doppler data was used for the numerical simulation. Spatial pattern of blood flow velocity and recirculation area were drawn through out the selected segment of coronary models. Wall shear stresses in the intracoronary stent models were calculated from three-dimensional computer simulation. A negative shear stress region, which is consistent with re-circulation area on flow pattern, was noted on the inner wall of post-stenotic area of pre-stenting model. The negative shear stress was disappeared after stenting. Shear stress in the post-stenting model was markedly reduced up to about two orders of magnitude compared to that of the pre-stenting model.

• The Korean Society of Law and Medicine
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• v.18 no.2
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• pp.163-194
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• 2017

Coronary artery disease has increased in Korea as the country enters the aged society. It is well known that the incidence of coronary artery disease is related to aging, hypertension, diabetes, hyperlipidemia, and dietary habit. For effective treatment of significant coronary stenosis, close coordination between cardiac surgery and cardiology team is essential. Especially cardiologists' decision whether to do the stent placement or CABG is very important because the cardiologists usually start to consult the patients for their treatment. Recently, non-surgical interventions(that is stent placement) in cardiology field have dramatically increased as the national insurance system removed the limitation of the number of stents deployed. However, accidents are often caused by inappropriate use of stents, especially in patients with triple coronary disease or left main disease with heavy coronary calcifications. Another aspect of stent placement is to cope with an emergency case in the event of coronary rupture or pericardial tamponade during coronary interventions without cardiac surgeons. In the past two years, the Korea Consumer Agency (Consumer Dispute Coordination Committee) analyzed eight cases of medical dispute settlement. Only two hospitals were manned with both cardiologists and cardiac surgeons. Seven patients died of procedures of stenting and five patients died on the day of the procedure. Among the 8 cases, 5 cases showed 3 vessel disease and the rest of the cases had either severe calcification, complete occlusion or poor coronary antomies for stenting According to a 2017 national data registry of coronary stenting, less than 3 drug-eluting stents were implanted in 98% of all patients. In 2015, the number of stent procedures was 38,922, and approximately in 800 (2%) cases, more than four stents were used per patient. We emphasize that it is necessary to seriously consider the cost-benefit analysis between stent and CABG. The patient has the right to choose the right procedure by asking the liability of 'instruction explanation obligation'. He should be well informed of the pros and cons of both procedures to avoid overuse of stent. It can be solved by intimate discussion of individual cases with the cardiac surgeon and the patient. Unilateral dialogue with the patient, forceful restriction on the number of stenting, lack of surgeon's backup in difficult cases should all be avoided. It is also necessary to solve the problem not only at the hospital level, such as multidisciplinary integrated medical care, but also a nationwide solution such as expanding cardiac surgeons as essential personnel to public officials.