• Nuclear Medicine and Molecular Imaging
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• 제40권2호
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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.

• 대한핵의학회:학술대회논문집
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• 대한핵의학회 1999년도 제38차 춘계학술대회
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• pp.228-241
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• 1999

Percutaneous coronary angioplasty is well established therapeutic modality in the management of coronary artery disease. However, the high restenosis rate of 30 to 50% limits its usefulness. The principal mechanism of restenosis, intimal hyperplasia, is the proliferative response of vessel wall to injury, which consists largely of smooth muscle cells. A large body of animal investigations and a limited number of clinical studies have established the ability of ionizing radiation to reduce neointimal proliferation and restenosis rate significantly. Human studies have been reported that intravascular radiation after first restenosis inhibits a second restenosis. Encouraged by these reports, we are also conducting a double blind, placebo-controlled, randomized trial to evaluate this new therapeutic modality in patients with coronary artery stenosis. The objective of our trial is to determine the safety and efficacy of catheter-based solutional beta emitting radioisotope system in preventing restenosis after angioplasty. This review describes the vascular brachytherapy systems and isotopes that have been utilized in the initial clinical trials performed in this area of post PTCA coronary restenosis. The results of many worldwide ongoing clinical trials will determine whether this new technology will change the future practice of vascular intervention.

• 대한핵의학회:학술대회논문집
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• 대한핵의학회 2001년도 제40차 춘계학술대회 및 연수교육
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• pp.24-34
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• 2001

Restenosis remains a major limitation of percutaneous coronary interventions. Numerous studios including pharmacological approaches and new devices failed to reduce the restenosis rate except coronary stenting. Since the results of $BENESTENT^{1)}\;and\;STRESS^{2)}$ studies came out, coronary stenting has been the most popular interventional strategy in the various kinds of coronary stenotic lesions, although the efficacy of stenting was shown only in the discrete lesion of the large coronary artery. The widespread use of coronary stenting has improved the early and late outcomes after coronary intervention, but it has also led to a new and serious problem, e.g., in-stent restenosis. Intravascular radiation for prevention of restenosis is a new technology in the field of percutaneous coronary intervention. Recent animal experiments and human trials have demonstrated that local irradiation, in conjunction with coronary interventions, substantially diminished the rate of restenosis. This paper reviews basic radiation biology of intracoronary radiation and its role in the inhibition of restenosis. The current status of intracoronary radiation therapy using Re-188 liquid balloon is also discussed.

• 대한핵의학회:학술대회논문집
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• 대한핵의학회 1999년도 제38차 춘계학술대회
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• pp.205-208
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• 1999

재협착에 관여하는 인자는 매우 다양하다. 평활근 세포의 증식, ECM의 형성, 혈관벽의 초기 혈전형성, 그리고 혈관 재형성 등이 모든 것들이 재협착의 병인에 기여하고 있다. 환자마다 이런 요소들의 기여정도가 다르며 동일 환자에서도 병변에 따른 기여정도가 또한 다르리라 여긴다. 그러나 아직까지 우리는 외막섬유모세포의 역할, 내피세포의 재생, 증식세포의 계획된 죽음 등 재협착의 기전을 불완전하게 이해하고 있고 따라서 보다 완전한 이해를 통해 효과적인 재협착 예방치료가 시행될 수 있을 것이다.

• 대한영상의학회지
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• 제85권2호
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• pp.258-269
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• 2024

관상동맥병 환자의 치료에 풍선팽창스텐트 치료는 현재 가장 흔히 시행되는 관상동맥재개통 치료법이다. 그러나 경피적 관상동맥 중재술 이후 재협착은 여전히 주요 합병증으로 남아 있다. 스텐트 재협착을 진단하기 위한 도구로서 관상동맥 CT 조영술(coronary CT angiography; 이하 CCTA)는 과거에는 주로 번짐허상과 움직임허상으로 인해 내강을 정확히 판단하기 어려워 그 역할이 제한적이었다. 따라서 정확한 확인을 위해서 침습적인 고식적 관상동맥 조영술로 넘어가는 경우가 많았다. 그러나 근래 CT 기술의 발달로 민감도와 특이도가 모두 개선되면서 그 역할이 중요해지고 있으며, 특히 일관되게 음성예측도가 높게 보고되고 있다. 본 종설에서는 CCTA를 이용한 관상동맥 스텐트 재협착 진단의 과거와 현재, 그리고 최신 동향에 대해 알아보고자 한다.

• 성인간호학회지
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• 제12권1호
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• pp.30-39
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• 2000

Coronary intervention is now a well established method for the treatment of coronary artery disease. Coronary restenosis is one of the major limitations after coronary intervention. So medical teams advise the patients to get the follow-up coronary angiogram in 6 months after coronary intervention to know if the coronary artery stenosis recurs or not. This study was done in order to know how many patients complied with the advice, and to identify the relative factors to the compliance with getting the follow-up coronary angiogram. The subjects were 101 patients (male: 58 female: 22, mean age: $61{\pm}15$), who received coronary interventions from Jan. 1st to Mar. 31st 1997, and their data were collected from them by questionnaires one year after intervention. The questionnaires consisted of family support scale, self efficacy scale and compliance with sick role behavior scale. The result may be summarized as follows. 1. The number of patients who complied with getting the follow-up coronary angiogram were 37 people(36.6%) and did not comply with it were 64 people(63.4%). All scores of family support(t=5.56, p<.0001), self efficacy (t=4.13, p<.0001) and compliance with sick role behavior(t=5.66, p<.0001) were significantly higher in the patients who got the follow-up coronary angiogram than in those who did not get it. But there was not any relative factor in demographic variables (p>.05). 2. The major motivations for getting follow-up coronary angiogram were recurrence of subjective symptom(40.5%), the advice of medical team(32.4%), and fear of recurrence (27.1%). The restenosis rate in patients who got the follow-up coronary angiogram was 37.8%. 3. The restenosis rate was higher in the patients who had subjective symptoms than in those who did not have any subjective symptom. So subjective symptom and restenosis rate showed a high positive correlation(r=39.9, p<.001). However, 27.2% of the patients who did not have any subjective symptom showed coronary restenosis. 4. The reasons why they did not get the follow-up coronary angiogram were economic burden(37.5%), improved symptom(34.4%), busy life schedule(10.9%), fear of invasive procedure(9.4%), negative reaction of family member(3.1%), no helper for patient(3.1%) and worry about medical team's mistake (1.6%). The relative fators on compliance with getting the follow-up coronary angiogram after coronary intervention were family support, self-efficacy and Compliance with sick role behavior. And the most important reason why the patients did not get the follow-up coronary angiogram after coronary intervention was an economic burden.

• 대한핵의학회지
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• 제39권2호
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• pp.114-117
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• 2005

As the indication of percutaneous coronary intervention (PCI) has expanded to the more difficult and complicated cases, frequent restenosis is still expected after PCI. According to AHA/ACC guideline of the present time, routine use of myocardial perfusion single photon emission tomography (SPECT) is not recommended after coronary intervention, but symptom itself or exercise EKG is not enough for the detection of restensis or for the prediction of event-free survival. In high risk and/or symptomatic subjects, direct coronary angiography is required myocardial perfusion SPECT could detect restenosis in 79% of the patients if performed 2 to 9 months after PCI. Reversible perfusion decrease in the myocardial perfusion SPECT is known to be the major prognostic indicator of major adrerse cardiac event in PCI patients and also the prognosis is benign in the patients without reversible perfusion decrease. Though the cumulated specificity is 79% in the literature and optimal timing of myocardial perfusion SPECT is in controversy, SPECT is recommended even in asymptomatic patients at 3 to 9 months after PCI. Considering the evidences recently reported in the literature, myocardial perfusion SPECT is useful for risk stratification and detection of coronary artery restenosis requiring re-intervention in the asymptomatic patients after PCI.

• 대한핵의학회:학술대회논문집
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• 대한핵의학회 1999년도 제38차 춘계학술대회
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• pp.209-221
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• 1999

Coronary restenosis is still regarded as Achilles' Hill of interventional cardiology despite relentless efforts of many investigators. Recent experimental and clinical studies have suggested that both gamma and beta radiation can reduce restenosis after angioplasty. Currently, intracoronary brachytherapy for the prevention of restenosis has become a new evolving treatment modality in interventional cardiology. This report discusses a physical aspect of gamma and beta radiation, initial clinical results and delivery systems used in intracoronary brachytherapy. We shall take a brief overview of methods and their advantages in intra-coronary brachytherapy. Future work should provide further insight for the best way of treating restenosis.

• International Journal of Vascular Biomedical Engineering
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• 제1권1호
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• pp.13-23
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• 2003

Backgrounds: The present study in angulated coronary stenosis was to evaluate the influence of velocity and wall shear stress (WSS) on coronary atherosclerosis, the changes of hemodynamic indices following coronary stenting, as well as their effect of evolving in-stent restenosis using human in vivo hemodynamic parameters and computed simulation quantitatively and qualitatively. Methods: Initial and follow-up coronary angiographies in the patients with angulated coronary stenosis were performed (n=80). Optimal coronary stenting in angulated coronary stenosis had two models: < 50 % angle changed(model 1, n=43), > 50% angle changed group (model 2, n=37) according to percent change of vascular angle between pre- and post-intracoronary stenting. Flow-velocity wave obtained from in vivo intracoronary Doppler study data was used for in vitro numerical simulation. Spatial and temporal patterns of velocity vector and recirculation area were drawn throughout the selected segment of coronary models. WSS of pre/post-intracoronary stenting were calculated from three-dimensional computer simulation. Results: Follow-up coronary angiogram demonstrated significant difference in the percent of diameter stenosis between two groups (group 1: $40.3{\pm}30.2$ vs. group 2: $25.5{\pm}22.5%$, p<0.05). Negative WSS area on 3D simulation, which is consistent with re-circulation area of velocity vector, was noted on the inner wall of post-stenotic area before stenting. The negative WSS was disappeared after stenting. High spatial and temporal WSS before stenting fell into within physiologic WSS after stenting. This finding was prominent in Model 2 (p<0.01) Conclusions: The present study suggests that hemodynamic forces exerted by pulsatile coronary circulation termed as WSS might affect on the evolution of atherosclerosis within the angulated vascular curvature. Moreover, geometric change, such as angular difference between pre / post-intracoronary stenting might give proper information of optimal hemodynamic charateristics for vascular repair after stenting.

• 대한한방내과학회지
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• 제44권3호
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• pp.387-401
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• 2023

Objective: This study was conducted to investigate the preventive effect of herbal medicines on restenosis after percutaneous coronary intervention (PCI) by reviewing randomized controlled trials (RCTs). Methods: RCTs were searched for herbal medicine treatment after PCI using eight online databases (PubMed, CNKI, Wanfang, J-STAGE, OASIS, ScienceON, KTKP, and KISS). Studies that confirmed restenosis through coronary angiography at follow-up were selected according to the inclusion and exclusion criteria. The primary outcome was the restenosis rate, and the secondary outcome was the angina recurrence rate. Data were extracted from the final selected studies according to the research methodology and then analyzed with Review Manager 5.4.1. Study quality was assessed using Cochrane's risk-of-bias (RoB) tool. Results: Of the 252 papers obtained through the primary search, nine studies that met the selection criteria were finally selected. In these nine studies, herbal medicine combined with western medicine was used for the experimental group, and western medicine treatment was used alone for the control group. The meta-analysis result revealed that the restenosis rate and angina recurrence rate were significantly lower in the experimental group than in the control group (RR=0.34, 95% CI: 0.22-0.53, p<0.00001, I²=0% and RR=0.47, 95% CI: 0.29-0.78, p=0.004, I²=0%, respectively). Furthermore, the quality of studies assessed by Cochrane's RoB was low. Conclusions: This study showed that the combined treatment of herbal medicine and western medicine was effective in preventing restenosis and angina after PCI. As the number of papers included in this study was small, a large number of high-quality clinical studies should be considered in the future.