ECG-gated MDCT를 이용한 Cardiac CT에서 ECG editing의 유용성과 고찰

강민수(Min Soo Kang),김상현(Sang Hyun Kim),대창민(Chang Min Dae),민관홍(Kwan Hong Min),김성룡(Sung Yong Kim) 대한전산화단층기술학회 2007 대한CT영상기술학회지 Vol.9 No.1

Purpose After spreading the 16 slice MDCT (Multi Detector Computed Tomography) in 2002, Cardiac scan with MDCT has been U5ing for patients presenting angina pectoris and atypical chest pain. Multi segmentation recon is generally U5ed for the cardiac scan. ECG-gating is also essential for that recon. When ECG-gating does not perform properly because of arrhythmia, ECG editing can be useful. The efficiency of ECG-gated MDCT using ECG editing will be mentioned through this paper. Materials and Methods 36 patients (37age ~ 87age: average age : 55, male : 14 female : 22) with ECG-gated MDCT who had been compensated by ECG editing were chosen for objections. 64-slice MDCT (BrillianceTM CT (64 slice), Philips Medical Systems, Netherlands) and Dual auto injector (Stellant, Medrad, USA) were used. After raw data with ECG-gating was compensated by software, chamber view and volume rendering image were obtained. After comparing the pre and post of compensated images, five grades were classified as Very good (all vessels are distinct), Good (vessels more than one are dear), Moderate (all vessels are connected vaguely), Bad (vessels are looked in disconnect way), Very bad( It is difficult to distinguish what it is) Results Among 36 patients before the exam there were 11 patients presenting arrhythmia and 6 patients presenting seismic heart rate. After analyzing 36 patients with ECG editing, there were 11 cases removing the R point because of arrhythmia, 19 cases removing the wrong R point because of the large T wave and 6 cases compensating the R point because the modality recognize it differently. Among these results there were 16 cases that had better improvement, 8 cases that were good, 7 cases that were bad and 5 case that was worse. During 10 months 36 patients were needed the ECG editing, males had more proportion than females (62%). ECG editing was necessary for the patients presenting arrhythmia through CT scan. Even though there were 1 case that had bad improvement, 4 cases had better improvement out of 11 patients. In case that R point was removed because of large T wave, 10 cases had better improvement out of 19 patients. Lastly, in case that R point was not rated properly because of the variation of ECG, there were 4 cases out of 6 cases that had no difference between pre and post of editing. Conclusion The proportion of Good to Bad is 24 to 12. The fact was founded that the ECG editing has a great effect on the recon- images. However, there are some limitations. Firstly, common points among the patients who had the worse result of editing could not be founded. Secondly, there was no assessment whether the patients’ respiration was controlled properly or not.

ECG신호의 QRS 폭과 RR Interval의 패턴을 이용한 효율적인 VEB 비트 검출 알고리듬

정용주,Chung, Yong-Joo 한국융합신호처리학회 2011 융합신호처리학회 논문지 (JISPS) Vol.12 No.2

In recent days, the demand for the remote ECG monitoring system has been increasing and the automation of the monitoring system is becoming quite of a concern. Automatic detection of the abnormal ECG beats must be a necessity for the successful commercialization of these real time remote ECG monitoring system. From these viewpoints, in this paper, we proposed an automatic detection algorithm for the abnormal ECG beats using QRS width and RR interval patterns. In the previous research, many efforts have been done to classify the ECG beats into detailed categories. But, these approaches have disadvantages such that they produce lots of misclassification errors and variabilities in the classification performance. Also, they require large amount of training data for the accurate classification and heavy computation during the classification process. But, we think that the detection of abnormality from the ECG beats is more important that the detailed classification for the automatic ECG monitoring system. In this paper, we tried to detect the VEB which is most frequently occurring among the abnormal ECG beats and we could achieve satisfactory detection performance when applied the proposed algorithm to the MIT/BIH database. 최근 들어 실시간 원격 ECG모니터링 시스템에 대한 수요가 늘어가고 있으며 가입자의 증가와 더불어 실시간 모니터링 시스템의 자동화에 대한 필요성이 대두되고 있다. 비정상적인 ECG 비트의 자동검출은 이러한 실시간 원격 ECG모니터링 시스템의 성공적인 상업화를 위해서는 반드시 필요한 요소기술이다. 본 논문에서는 이러한 점에 착안하여 QRS 폭(width)과 RR interval의 패턴을 이용한 효율적인 비정상적 ECG 비트 자동검출알고리듬을 제안하였다. 기존에는 주로 ECG 비트의 상세한 분류에 대해서 많은 연구가 이루어졌으나 이러한 방법들은 분류 오류가 많고 주변 환경이 변화함에 따라서 분류성능의 변동성이 심하다는 단점이 있었다. 또한 정확한 ECG 비트 분류를 위해서는 충분한 양의 훈련데이터를 필요로 하며 특히 분류시에 많은 계산량을 필요로 한다는 문제점도 있었다. 그러나 자동화된 원격 ECG모니터링 시스템을 위해서는 ECG 비트의 세세한 분류 보다는 비트의 정상여부판단이 더 중요하다. 이러한 점에 착안하여 본 논문에서는 ECG 신호의 비정상적인 비트중에서도 가장 빈번이 발생하는 VEBs(Ventricular ectopic beats) 비트의 검출을 시도하였고 제안된 알고리듬을 MIT-BIH 부정맥 데이터베이스에 적용한 결과 만족스러운 VEBs 바트 검출성능을 얻을 수 있었다.

Biological Activity of Recombinant Equine Chorionic Gonadotropin in other Specie Receptor Cells.

So Yun Lee,Munkhzaya Byambaragchaa,Jung Min Kim,Mi Hyang Yoo,Jeong Soo Kim,Kwan-Sik Min 한국수정란이식학회 2016 한국수정란이식학회 학술대회 Vol.2016 No.10

Equine chorionic gonadotropin (eCG) is a member of the glycoprotein hormone. eCG, over 40%, is a heavily glycosylated glycoprotein than other glycoprotein hormones. eCG is composed of non-covalently linked α and β subunit. The α subunit is common to all glycoprotein hormones, whereas the β subunit was known distinct sequences and specific receptor binding. Unusually, eCG shows both FSH and LH activities in other species. eCG α subunit has two N-glycosylation sites (Asn56, Asn82) and β subunit has one N-glycosylation site (Asn13) and about 13 O-glycosylation sites in the C-terminal region. We constructed 3 type mutants (βα△56: α-subunit Asn56→ Gln56; β-Da: β-subunit C-terminal deletion; β-Dα△56: β C-terminal deletion & α Asn56→Gln56) in the tethered eCGβα (wild type) and all mutants included myc-tag between first and second amino acid of β subunit. The plasmid DNAs cloned into pcDNA3 mammalian expressing vector were transiently transfected into CHO-Suspension cells. We also constructed rat LH/CG receptor and rat FSH receptor into pcDNA3 expression vector. These receptors were transiently transfected into CHO-K1 cell. Each receptor cells were used for further assays at 3 days after transfection. cAMP and IP-one were evaluated by CISBIO cAMP HiRange and IP-one kits using the rec-eCGβα mutants. According to cAMP assay results, IC50 values of 4 type ligand treatment in the rat FSH receptor cells were: eCGβα: IC50_16.8841; eCGβα56: IC50_95.6099; eCGβ-Dα: IC50_395.0087; eCGβ-Dα56: IC50_1439.8702. In the rat LH/CG receptor cells of 4 types ligand treatments, cAMP results were: eCGβα: IC50_0.9760; eCGβα56: IC50_8.3884; eCGβ-Dα: IC50_9.2550; eCG β-Dα56: IC50_45.9439. As seen in these data, β C-terminal region and α Asn56 play an important role in rat FSHR and rat LH/CGR, respectively. And rat LHCG receptor cells was remarkably stronger than rat FSH receptor cells. According to IP-one assay, IC50 values in rat FSH receptor cells, the results were: eCGβα: IC50_561.4490; eCGβα56: IC50_361.3005; eCGβ-Dα: IC50_911.8577; eCGβ-Dα56: IC50_139.1193. And in rat LH/CG receptor cells, IP-one results were: eCGβα: IC50_422.7315; eCGβα56: IC50_406.4915; eCGβ-Dα: IC50_537.8300; eCGβ-Dα56: IC50_254.2004. As shown in these data, IP-one result was a little different to cAMP result. The β eCGβ-Dα56 of IC50 value was shown generally high signal. Now we are trying to analyse role of C-terminal region of eLH/CGR with cAMP, IP-one and ERK signal transduction assays.

Luteinizing hormone-like and follicle-stimulating hormone-like activities of equine chorionic gonadotropin β-subunit mutants in cells expressing rat luteinizing hormone/chorionic gonadotropin receptor and rat follicle-stimulating hormone receptor

BYAMBARAGCHAA MUNKHZAYA,박아영,길소진,이해원,고윤정,최승희,강명화,민관식 한국통합생물학회 2021 Animal cells and systems Vol.25 No.3

To identify the specific region of eCG involved in FSH-like activity, the following mutant expression vectors were constructed targeting the amino acid residues 102–104 of the eCG β-subunit: single mutants, eCGβV102G/α, eCGβF103P/α, and eCGβR104K/α; double mutants, eCGβV102G;F103P/α, eCGβV102G;R104K/α, and eCGβF103P;R104K/α; triple mutant, eCGβV102G;F103P;R104K/α. The LH-like and FSH-like activities of eCG mutants were examined in CHO-K1 cells expressing rat LH/ CG receptor and rat FSH receptor. The levels of eCGβV102G/α, eCGβR104K/α, and eCGβV102G; R104K/α in the culture supernatant were markedly lower than those of eCGβ/α-wt. The other mutants and rec-eCGβ/α-wt were efficiently secreted into the culture supernatant. The LH-like activities of eCGV104G/α, eCGβV102G;R104K/α, and eCGβF103P;R104K/α were approximately 61%, 52%, and 54%, respectively, of those of eCG-wt. The Rmax values of the mutants were 58.9%–78.8% those of eCG-wt with eCGβR104K/α exhibiting the lowest value. The FSH-like activities of single mutants were only 16%–20% of those of eCG-wt. Additionally, the FSH-like activity of double mutants was less than 10% of that of eCG-wt. In particular, the FSH-like activities of βV102G;R104K/α and βF103P;R104K/α were 2.5–2.9% of that of eCG-wt. These results suggest that the amino acid residues 102–104 of the eCG β-subunit are dispensable and that the residue 104 of the eCG β-subunit plays a pivotal role in signal transduction through the rat FSH receptor. Thus, these mutants may aid future studies on eCG interactions with mammalian FSH receptors in vitro and in vivo.

Biochemical Characterization of Recombinant Equine Chorionic Gonadotropin (rec-eCG), Using CHO Cells and PathHunter Parental Cells Expressing Equine Luteinizing Hormone/Chorionic Gonadotropin Receptors (eLH/CGR)

So-Yun Lee(이소연),Munkhzaya Byambaragchaa(뱜바락차 뭉흐자야),Jeong-Soo Kim(김정수),Hun-Ki Seong(성훈기),Myung-Hwa Kang(강명화),Kwan-Sik Min(민관식) 한국생명과학회 2017 생명과학회지 Vol.27 No.8

eCG는 다른 포유동물에서 FSH와 LH의 활성을 나타내기 때문에 성선자극 호르몬 family에서 아주 특이적이고 많은 당쇄가 수식되어진 알파와 베타의 비공유결합으로 구성되어 있다. 유전자 재조합 eCGβ/α의 생물학적 기능을 규명하기 위하여 말의 LH/CGR의 포유동물발현용 벡터를 구축하였다. 재조합 eCGβ/α의 활성분석은 말의 LH/CGR가 일시적으로 발현되는 CHO-K1 세포와 지속적으로 발현되는 PathHunter Parental 세포를 이용하여 분석하였다. 유전자 재조합 eCGβ/α는 CHO-K1 부유세포의 상층으로 효율적으로 분비되었으며, 분비량은 transfection 후 1일에서 7일까지 약 200 mIU/ml이었다. Western blot 분석결과는 재조합 eCGβ/α의 분자량은 약 40-45 kDa으로 검출되었다. eLH/CGR가 발현되는 CHO-K1 세포에서의 cAMP분비량으로 재조합 eCGβ/α의 활성을 분석하였다. 그 결과 cAMP농도는 재조합 eCGβ/α의 농도의존적으로 증가하였다. eLH/CGR가 일시적으로 발현하는 CHO-K1 세포에서 EC50 값은 8.1±6.5 ng이었다. 또한 일시적 및 지속적으로 eLH/CGR가 발현하는 PathHunter Parental 세포에서도 재조합 eCGβ/α의 LH 활성 분석결과 높은 활성을 나타내는 것으로 확인되었으며, 이들의 EC50 값은 각각 5.0±4.7 ng/ml, 4.5±5.2 ng/ml으로 나타났다. 따라서 이러한 결과에 의하면 재조합 eCGβ/α는 말의 LH/CGR가 발현하는 세포에서 생물학적 활성을 나타난다는 것을 확인하였으며, PathHunter Parental 세포에서 지속적으로 발현되는 세포의 확보는 당쇄제거에 의한 재조합 eCG의 돌연변이등에 관한 기능적인 메커니즘을 밝히는데 유용할 것으로 사료된다. Equine chorionic gonadotropin (eCG) consists of highly glycosylated α- and β-subunits and is a unique member of the gonadotropin family, because it elicits the response characteristics of follicle stimulating hormone (FSH) and luteinizing hormone (LH) in species other than the horse. To directly assess the biological function of rec-eCGβ/α, we constructed mammalian expressing vectors of equine luteinizing hormone/chorionic gonadotropin receptors (eLH/CGR). The activity of rec-eCGβ/α in vitro assayed in transient transfected CHO-K1 cells and in stably transfected PathHunter Parental cells with eLH/CGR was investigated. rec-eCGβ/α was efficiently secreted in the CHO-K1 suspension cell media, and the quantity detected was about 200 mIU/ml from 1 to 7 days after transfection. In the western blot analysis, the rec-eCGβ/α protein was broadly identified to be about 40~45 kDa molecular weight. The cAMP stimulation in CHO-K1 cells expressing eLH/CGR was determined to evaluate the activity of rec-eCGβ/α. The cAMP concentration increased in direct proportion to the concentration of the rec-eCGβ/α. The EC50 value in the transient transfected CHO-K1 cells was 8.1±6.5 ng. The stable cell lines of eLH/CGR were established in the PathHunter Parental cells expressing β-arrestin. We found that rec-eCGβ/α had full LH activity in the PathHunter Parental cells expressing eLH/CGR. The EC50 value in transient and stable cells was 5.0±4.7 ng/ml and 4.5±5.2 ng/ml, respectively. These results suggest that rec-eCGβ/α has a biological activity in a cell expressing eLH/CGR. These stable cells expressed in PathHunter Parental cells could be useful for elucidating the functional mechanisms of deglycosylated rec-eCGβ/α mutants.

Arrhythmia 환자의 Coronary Computed Tomography Angiography에서 ECG-triggered FLEX Scan Mode 사용 시 선량과 영상의 질에 대한 연구

유흥준(Heung Joon Yoo),김민정(Min Jung Kim),박정훈(Jung Hoon Park) 대한CT영상기술학회 2013 대한CT영상기술학회지 Vol.15 No.1

서론 : 본 연구의 목적은 부정맥이 있는 환자를 대상으로 DSCT를 이용한 CCTA 검사에서 Retrospective ECG-gated helical scan mode와 Adaptive Cardio Sequence 기능을 갖고 있는 ECG-triggered FLEX scan mode를 통해 검사하였을 경우의 선량과 영상의 질을 비교 분석하여 임상에서의 유용성을 평가하고자 한다. 대상 및 방법 : 2012년 2월부터 2012년 12월까지 본원에서 CCTA 검사를 시행한 환자 중에서 심전도 동조 시 부정맥을 보이는 63명의 환자를 대상으로 하였으며, 33명은 ECG-triggered FLEX scan mode를 사용 하였고, 30명은 Retrospective ECG-gated helical scan mode를 사용하여 검사를 시행하였다. 각 mode별 유효 선량과 영상의 질을 비교 분석하였다. 결과 : 유효 선량의 평균값은 retrospective ECG-gated helical scan mode에서는 5.67mSv, ECG-triggered FLEX scan mode에서는 3.55mSv 였다. 평균적으로, ECG-triggered FLEX scan mode에서 선량이 37% 더 낮았다(P=0.002). ECG-triggered FLEX scan mode 그룹에서 영상의 질이 높이 평가 되었으며, 환자의 부정맥 패턴에 따라서는 심방세동에서 만큼은 ECG-triggered FLEX scan mode보다 retrospective ECG-gated helical scan mode에서 영상의 질이 더 높게 평가 되었으나, 통계학적 차이는 보이지 않았다. 결론 : 부정맥이 있는 환자의 CCTA 검사에서 advanced arrhythmia rejection 알고리즘을 이용한 ECG-triggered FLEX scan mode로 검사하였을 경우 retrospective ECG-gated helical scan mode로 검사 했을 때보다 피폭선량을 효과적으로 줄이면서도 영상의 질을 유지할 수 있다. Purpose : To determine clinical usefulness of ECG-triggered FLEX scan mode for patients with irregular heart rhythm in CCTA by comparing radiation dose and image quality with retrospective ECG-gated helical scan mode. Materials and methods : We selected 63 patients who showed arrhythmia in ECG monitoring in CCTA from February to December 2012. We divided these patients into two groups and performed CCTA using retrospective ECG-gated helical scan mode(n=33) and ECG-triggered FLEX scan mode(n=30). Then, we compared effective dose and image quality between two groups. Results : In retrospective ECG-gated helical scan mode, mean value of effective dose was 5.67 mSv and in ECG-triggered FLEX mode, 3.55 mSv, respectively. On average, radiation dose in ECG-triggered FLEX scan mode was 37% lower(P=0.02). Subjective score of image quality was higher in ECG-triggered FLEX scan mode groups except atrial fibrillation case. However, there was no statistical significance. Conclusion : In case of performing CCTA for patients having arrhythmia, radiation dose in ECGtriggered FLEX scan mode with advanced arrhythmia rejection algorhythm is 37% lower than that in retrospective ECG-gated helical scan mode without deteriorating image quality.

Signal Transduction of Eel Luteinizing Hormone Receptor (eelLHR) and Follicle Stimulating Hormone Receptor (eelFSHR) by Recombinant Equine Chorionic Gonadotropin (rec-eCG) and Native eCG

Byambaragchaa, Munkhzaya,Lee, So-Yun,Kim, Dae-Jung,Kang, Myung-Hwa,Min, Kwan-Sik The Korean Society of Developmental Biology 2018 발생과 생식 Vol.22 No.1

Previous studies showed that recombinant equine chorionic gonadotropin ($rec-eCG{\beta}/{\alpha}$) exhibits both follicle-stimulating hormone (FSH) and luteinizing hormone (LH)-like activities in rat LHR- and FSHR-expressing cells. In this study, we analyzed signal transduction by eelFSHR and eelLHR upon stimulation with $rec-eCG{\beta}/{\alpha}$ and native eCG. The cyclic adenosine monophosphate (cAMP) stimulation in CHO-K1 cells expressing eelLHR was determined upon exposure to different doses (0-1,450 ng/mL) of $rec-eCG{\beta}/{\alpha}$ and native eCG. The $EC_{50$ values of $rec-eCG{\beta}/{\alpha}$ and native eCG were 172.4 and 786.6 ng/mL, respectively. The activity of $rec-eCG{\beta}/{\alpha}$ was higher than that of native eCG. However, signal transduction in the CHO PathHunter Parental cells expressing eelFSHR was not enhanced by stimulation with both agonist $rec-eCG{\beta}/{\alpha}$ and native eCG. We concluded that $rec-eCG{\beta}/{\alpha}$ and native eCG were completely active in cells expressing eelLHR, similar to the activity in the mammalian cells expressing LHRs. However, $rec-eCG{\beta}/{\alpha}$ and native eCG did not invoke any signaling response in the cells expressing eelFSHR. These results suggest that eCG has a potent activity in cells expressing eelLHR. Thus, we also suggest that $rec-eCG{\beta}/{\alpha}$ can induce eel maturation by administering gonadotropic reagents (LH), such as salmon pituitary extract.

Internalization of Rat FSH and LH/CG Receptors by rec-eCG in CHO-K1 Cells

박종주,성훈기,김정수,Byambaragchaa Munkhzaya,강명화,민관식 한국발생생물학회 2017 발생과 생식 Vol.21 No.2

Equine chorionic gonadotropin (eCG) is a unique molecule that elicits the response characteristics of both fol-licle-stimulating hormone (FSH) and luteinizing hormone (LH) in other species. Previous studies from this laboratory had demonstrated that recombinant eCG (rec-eCG) from Chinese hamster ovary (CHO-K1) cells exhibited both FSH- and LH-like activity in rat granulosa and Leydig cells. In this study, we analyzed receptor internalization through rec-eCGs, wild type eCG (eCGβ/α) and mutant eCG (eCGβ/αΔ56) with an N-linked oligosaccharide at Asn56 of the α-subunit. Both the rec-eCGs were obtained from CHO-K1 cells. The agonist activation of receptors was analyzed by measuring stimulation time and concentra-tions of rec-eCGs. Internalization values in the stably selected rat follicle-stimulating hormone receptor (rFSHR) and rat lute-inizing/chorionic gonadotropin receptor (rLH/CGR) were highest at 50 min after stimulation with 10 ng of rec-eCGβ/α. The dose-dependent response was highest when 10 ng of rec-eCGβ/α was used. The deglycosylated eCGβ/αΔ56 mutant did not enhance the agonist-stimulated internalization. We concluded that the state of activation of rFSHR and rLH/CGR could be modulated through agonist-stimulated internalization. Our results suggested that the eLH/CGRs are mostly internalized within 60 min by agonist-stimulation by rec-eCG. We also suggested that the lack of responsiveness of the deglycosylated eCGβ/ αΔ56 was likely because the site of glycosylation played a pivotal role in agonist-stimulated internalization in cells express-ing rFSHR and rLH/CGR.

Specific Biological Activity of Equine Chorionic Gonadotropin (eCG) Glycosylation Sites in Cells Expressing Equine Luteinizing Hormone/CG (eLH/ CG) Receptor

Munkhzaya Byambaragchaa,Seung-Hee Choi,Hyo-Eun Joo,Sang-Gwon Kim,Yean-Ji Kim,Gyeong-Eun Park,Myung-Hwa Kang,민관식 한국발생생물학회 2021 발생과 생식 Vol.25 No.4

Equine chorionic gonadotropin (eCG), produced by the endometrial cups of the placenta after the first trimester, is a specific glycoprotein that displays dual luteinizing hormone (LH)- like and follicle-stimulating hormone (FSH)-like effects in non-equid species. However, in equidaes, eCG exhibits only LH-like activity. To identify the specific biological functions of glycosylated sites in eCG, we constructed the following site mutants of N- and O-linked glycosylation: eCGβ/αΔ56, substitution of α-subunit56 N-linked glycosylation site; eCGβ-D/ α, deletion of the O-linked glycosylation sites at the β-subunit, and eCGβ-D/αΔ56, double mutant. We produced recombinant eCG (rec-eCG) proteins in Chinese hamster ovary suspension (CHO-S) cells. We examined the biological activity of rec-eCG proteins in CHO-K1 cells expressing the eLH/CG receptor and found that signal transduction activities of deglycosylated mutants remarkably decreased. The EC50 levels of eCGβ/αΔ56, eCGβ-D/ α, and eCGβ-D/αΔ56 mutants decreased by 2.1-, 5.6-, and 3.4-fold, respectively, compared to that of wild-type eCG. The Rmax values of the mutants were 56%-80% those of wildtype eCG (141.9 nmol/104 cells). Our results indicate that the biological activity of eCG is greatly affected by the removal of N- and O-linked glycosylation sites in cells expressing eLH/ CGR. These results provide important information on rec-eCG in the regulation of specific glycosylation sites and improve our understanding of the specific biological activity of receCG glycosylation sites in equidaes.

응급실에서 시행한 상용심전도의 효용성에 대한 고찰

도호석,이창현,이삼범,도병수 대한응급의학회 1995 대한응급의학회지 Vol.6 No.1

Study objectives : To determine whether routine performance of an ECG could have been safely avoided in a subset of ED(emergency department) patients admitted to a university hospital. Design : Retrospective consecutive case series. Setting : University teaching hospital. Type of participants : All patients admitted through Yeungnam university hospital during a three month period. Methods and interventions : Acceptable indications for an admission ECG were prospectively developed. Charts of all patients were reviewed to determine whether any of these were present, whether an admission ECG performed, and whether an admission ECG resulted in a change in patients management or outcome. Measurements and main result : There were 984 admissions through ED during the study period. Of these 608 patients had an ECG performed at ED. Of the 608 patients 140(23.0%) had at least one acceptable indication and 468(77.0%) had no for an ECG. Among the 140 who had an indication for an ECG at ED, 56(40.0%) patients ECG were interpreted abnormal (95% confidence interval[CI], 32%∼48%). Among the 468 who had no indications, only 3(0.64%) patients ECG were interpreted abnormal (95% CI, 0%∼1.36%) and the ECG result in a change in management, but no change in outcome (95% CI, 0%∼0.64%). Conclusion : The routine or admission ECG could have been avoided in no acceptable ED indication. We should have to try continuously for making acceptable criteria of ECG in ED of Korea, and then we have to prevent needless ECG and cardiac work up that increasing the cost and evacuation time from ED.