http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Kim, Byeong-Keuk,Kim, Jung-Sun,Park, Junbeom,Ko, Young-Guk,Choi, Donghoon,Jang, Yangsoo,Hong, Myeong-Ki Yonsei University College of Medicine 2012 Yonsei medical journal Vol.53 No.3
<P><B>Purpose</B></P><P>There is a lack of sufficient data in comparison of optical coherence tomographic (OCT) findings between first- and second-generation drug-eluting stents (DES). Compared to first-generation (i.e., sirolimus- or paclitaxel-eluting stents), second-generation DESs (i.e., everolimus- or biolinx-based zotarolimus-eluting stents) might have more favorable neointimal coverage.</P><P><B>Materials and Methods</B></P><P>Follow-up OCT findings of 103 patients (119 lesions) treated with second-generation DESs were compared with those of 139 patients (149 lesions) treated with first-generation DESs. The percentage of uncovered or malapposed struts, calculated as the ratio of uncovered or malapposed struts to total struts in all OCT cross-sections, respectively, was compared between the two groups.</P><P><B>Results</B></P><P>Both DES groups showed similar suppression of neointimal hyperplasia (NIH) on OCT (mean NIH cross-sectional area; second- vs. first-generation=1.1±0.5 versus 1.2±1.0 mm<SUP>2</SUP>, respectively, <I>p</I>=0.547). However, the percentage of uncovered struts of second-generation DESs was significantly smaller than that of first-generation DESs (3.8±4.8% vs.7.5±11.1%, respectively, <I>p</I><0.001). The percentage of malapposed struts was also significantly smaller in second-generation DESs than in first-generation DESs (0.4±1.6% vs.1.4±3.7%, respectively, <I>p</I>=0.005). In addition, intra-stent thrombi were less frequently detected in second-generations DESs than in first-generation DESs (8% vs. 20%, respectively, <I>p</I>=0.004).</P><P><B>Conclusion</B></P><P>This follow-up OCT study showed that second-generation DESs characteristically had greater neointimal coverage than first-generation DESs.</P>
Kim, Gwang-Sil,Kim, Byeong-Keuk,Shin, Dong-Ho,Kim, Jung-Sun,Hong, Myeong-Ki,Gwon, Hyeon-Cheol,Kim, Hyo-Soo,Yu, Cheol Woong,Park, Hun Sik,Chae, In-Ho,Rha, Seung-Woon,Jang, Yangsoo Wolters Kluwer Health, Inc. All rights reserved. 2017 Coronary artery disease Vol.28 No.5
<P>Conclusion Clinical parameters such as age, diabetes, and heart failure were independent predictors of the composite of cardiac death, myocardial infarction, and stent thrombosis, whereas angiographic or procedural parameters such as lesion length and number of implanted stents were predictors of target-vessel revascularization. Clinical outcomes after CTO intervention were worse in patients with multiple risk factors. Copyright (C) 2017 Wolters Kluwer Health, Inc. All rights reserved.</P>
Kim, Byeong-Keuk,Kim, Jung-Sun,Ko, Young-Guk,Choi, Donghoon,Jang, Yangsoo,Hong, Myeong-Ki Kluwer Academic Publishers 2012 INTERNATIONAL JOURNAL OF CARDIOVASCULAR IMAGING Vol.28 No.6
<P>Minimal data have been published on the correlation between angiographic late loss (LL) and incomplete neointimal coverage of struts after drug-eluting stent (DES) implantation. Therefore, we evaluated the relationship between angiographic LL and the percentage of uncovered struts on follow-up optical coherence tomography (OCT) images, in all cross-sections of the lesions. From the OCT registry database, 219 lesions without restenosis after DES implantation were divided into tertiles based on angiographic LL: tertile I (LL 0.26 mm), tertile II (0.26 < LL < 0.59 mm), and tertile III (0.59 mm). Lesions with the percentage of uncovered struts in the highest quartile (75th percentile; >6.0%) were defined as highly uncovered; in an independent analysis, lesions without any uncovered strut(s) were defined as completely covered. Higher percentages of uncovered struts were observed in tertile I than in both tertile II and III (10.3 12.8% vs. 4.2 7.4% vs. 2.4 5.1%, respectively; P < 0.001 for I vs. II and I vs. III). Angiographic LL correlated significantly with the percentage of uncovered struts on OCT (r = -0.340, P < 0.001). The best cut-off values of angiographic LL to predict highly uncovered and completely covered lesions were 0.29 mm (area under curves [AUC] = 0.723, P < 0.001) and 0.61 mm (AUC = 0.692, P < 0.001), respectively. Angiographic LL inversely and significantly correlated with the percentage of uncovered struts on OCT after DES implantation.</P>
Kim, Choongki,Hong, Sung-Jin,Shin, Dong-Ho,Kim, Jung-Sun,Kim, Byeong-Keuk,Ko, Young-Guk,Choi, Donghoon,Jang, Yangsoo,Hong, Myeong-Ki Oxford University Press 2015 European heart journal cardiovascular Imaging Vol.16 No.12
<P><B>Aims</B></P><P>We sought to evaluate whether coronary computed tomographic angiography (CCTA) could accurately and reproducibly delineate the lumen and vessel contours of coronary arteries.</P><P><B>Methods and results</B></P><P>One hundred coronary stenotic lesions representing 91 patients with stable angina who received both CCTA and intravascular ultrasound (IVUS) were analysed. Three segments with minimal lumen cross-sectional area (CSA), proximal reference, and distal reference on IVUS images were selected for each lesion. Five observers measured lumen and vessel CSAs at three matching segments on CCTA images. These CSAs were compared with the IVUS-measured CSAs as a reference standard. All five observers underestimated lumen CSA at the three selected segments by CCTA. The minimal lumen CSA assessed by CCTA exhibited very weak correlations with those obtained by IVUS (<I>r</I> =0.23, 0.24, 0.15, 0.25, and 0.28, respectively). In contrast to the lumen CSA, the vessel CSA at the three segments was overestimated by all observers when assessed by CCTA. At the segment with minimal lumen CSA, the vessel CSA obtained by CCTA showed weak correlations with those assessed by IVUS (<I>r</I> = 0.43, 0.33, 0.44, 0.37, and 0.42, respectively). Moreover, intra-class correlation coefficients ranged from 0.44 to 0.73 among the five observers for lumen or vessel CSA measurements by CCTA at the segment with minimal lumen CSA.</P><P><B>Conclusion</B></P><P>CCTA has potential limitations in the accurate delineation of lumen and vessel contours in patients with angina, as there was a high level of discordance with the IVUS-measured lumen and vessel CSAs and high inter-observer variability.</P>
Kim, Bo Hyun,Ko, Young-Guk,Her, Ae-Young,Kim, Jung-Sun,Hwang, Ki-Chul,Shin, Dong-Ho,Kim, Byeong-Keuk,Choi, Donghoon,Ha, Jong-Won,Hong, Myeong-Ki,Jang, Yangsoo The Korean Society of Cardiology 2012 Korean Circulation Journal Vol.42 No.7
<P><B>Background and Objectives</B></P><P>Patients with acute myocardial infarction show varying degrees of collateral development. However, the relationships between angiogenic factors and degree of collaterals are not well known.</P><P><B>Subjects and Methods</B></P><P>Fifty-nine patients (mean age, 59±10 years) with ST-segment elevation myocardial infarction (STEMI) underwent primary percutaneous coronary intervention (PCI). Patients were divided into one of 2 groups: group I (Rentrop collateral grade 0/1, n=34) or group II (grade 2/3, n=25). Plasma levels of vascular endothelial growth factor (VEGF), soluble VEGF receptor (sFlt-1), angiopoietin (Ang)-2, and soluble Tie-2 at baseline, 24 and 48 hours after PCI were measured.</P><P><B>Results</B></P><P>There were fewer diabetic patients and higher incidence of previous angina and multi-vessel disease in group II. Group II had a lower left ventricular ejection fraction and a trend toward longer pain-to-balloon time. Plasma levels of Ang-2, sFlt-1 were elevated prior to primary PCI and decreased after PCI, whereas plasma level of VEGF was relatively low initially, however rose after PCI. sTie-2 levels showed no significant interval change in group I, but decreased over time in group II. VEGF, sFlt-1, and Tie-2 levels did not differ between the groups at each time point. However, plasma levels of Ang-2 were higher in group I than in group II at baseline and at 48 hours.</P><P><B>Conclusion</B></P><P>Presence of collaterals in STEMI patients undergoing primary PCI was associated with lesser rise in Ang-2 plasma level. VEGF showed a delayed response to acute ischemia compared to Ang-2. Clinical implications of our findings need to be investigated in further studies.</P>
Minimization of Tool-Path in NC Milling Operation
Kim, Byeong Keuk,Park, Joon Young,Wee, Nam Sook 동국대학교 산업기술연구원 1997 산업기술논문집 Vol.10 No.-
This paper describes new methods to minimize the cutting time in zigzag milling operation of two dimensional polygonal surfaces. Previous works have been focused mainly on experimental approaches by considering some machining parameters such as, spindle speed, depth of cut, cutter traverse rate, cutter diameter, number of teeth, and so on. However, in this study, we considered a geometrical factor, which is the length of cut. In an N-sided concave or convex polygon, an algorithm has been developed which minimize the total length of cut.
Byeong-Keuk Kim,Joo Young Yang,오승진,윤세정,전동운,고영국 연세대학교의과대학 2011 Yonsei medical journal Vol.52 No.5
Purpose: It is unknown whether cilostazol pretreatment reduces postprocedural myonecrosis (PPMN). Cilostazol pretreatment reduces PPMN after percutaneous coronary intervention (PCI). Materials and Methods: A total of 120 patients with stable angina scheduled for elective PCI were randomly assigned to a 7-day pretreatment with Cilostazol (200 mg/day) or to a control group. Creatine kinase-MB (CK-MB) and cardiac troponin I (cTnI) levels were measured at baseline and at 6 and 24 hours after PCI. The primary end-point was the occurrence of PPMN, defined as any CK-MB elevation above the upper normal limit (UNL). Aspirin and clopidogrel were co-administered for 7 days before PCI, and resistance to these agents was then assayed using the VerifyNow System. Results: There was no difference in baseline characteristics between the final analyzable cilostazol (n=54) and the control group (n=56). Despite a significantly greater % inhibition of clopidogrel in the cilostazol group (39±23% versus 25±22%, p=0.003), the incidence of PPMN was similar between the cilostazol group (24%) and the control group (25%, p=1.000). The rate of CK-MB elevation at ≥3 times UNL was also similar between the two groups (6% versus 5%, p=0.583). The incidence of cTnI increase over the UNL or to 3 times the UNL was not different between the two groups. There was no significant difference in terms of the rate of adverse events during follow-up, although the cilostazol group showed a tendency to have a slightly higher incidence of entry site hematoma. Conclusion: This trial demonstrated that adjunctive cilostazol pretreatment might not significantly reduce PPMN after elective PCI in patients with stable angina.