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Dive into the research topics where Ik Jun Choi is active.

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Featured researches published by Ik Jun Choi.


European Journal of Echocardiography | 2015

Impact of diabetes duration on the extent and severity of coronary atheroma burden and long-term clinical outcome in asymptomatic type 2 diabetic patients: evaluation by Coronary CT angiography

Jin-Jin Kim; Byung-Hee Hwang; Ik Jun Choi; Eun-Ho Choo; Sungmin Lim; Jae-Kyung Kim; Yoon-Seok Koh; Dong-Bin Kim; Sung-Won Jang; Eun Joo Cho; Jong Min Lee; Pum-Joon Kim; Jae-Hyoung Cho; Jung Im Jung; Ki-Bae Seung; James K. Min; Kiyuk Chang

AIMS We investigated the association between diabetes duration and the extent and severity of coronary artery disease (CAD) as well as long-term clinical outcomes using coronary computed tomography angiography (CCTA) in asymptomatic type 2 diabetic patients. METHODS AND RESULTS We analysed 933 asymptomatic type 2 diabetic patients without known CAD who underwent CCTA. Patients were divided into three groups according to the duration of diabetes: <5 years, 5-10 years, and ≥10 years. Stenosis by CCTA was scored as none (0%), non-obstructive (1-49%), or obstructive (≥50%) for each coronary artery segment. For these patients, we compared the prevalence, extent, and severity of CAD, including coronary artery calcium score (CACS), atheroma burden obstructive score (ABOS), segment involvement score (SIS), and segment stenosis score (SSS). Major adverse cardiac and cerebrovascular events (MACCE), including all-cause mortality, non-fatal myocardial infarction, and stroke, within a follow-up period were also compared.Patients with longer duration of diabetes possessed higher rates of obstructive CAD (P < 0.001). Patients with longer duration of diabetes also manifested greater degree of CACS, ABOS, SIS, and SSS (P < 0.001 for all) with associated higher rate of MACCE (P = 0.025). Presence of obstructive CAD as assessed by CCTA was an independent predictor of MACCE after adjusting for confounding risk factors (hazard ratio: 1.979, confidence interval: 1.178-3.327, P = 0.010). CONCLUSION In asymptomatic diabetic patients, longer diabetes duration is associated with a higher prevalence, extent, and severity of CAD as well as risk of MACCE. Moreover, greater CAD burden increases the risk of MACCE independent of co-existing CAD risk factors.


American Journal of Cardiology | 2014

Impact of the Stent Length on Long-Term Clinical Outcomes Following Newer-Generation Drug-Eluting Stent Implantation

Ik Jun Choi; Yoon-Seok Koh; Sungmin Lim; Jin Jin Kim; Mineok Chang; Minkyu Kang; Byung-Hee Hwang; Chan Jun Kim; Tae-Hoon Kim; Suk Min Seo; Dong Il Shin; Mahn Won Park; Yun-Seok Choi; Hun-Jun Park; Sung-Ho Her; Dong-Bin Kim; Pum-Joon Kim; Jong Min Lee; Chul Soo Park; Keon Woong Moon; Kiyuk Chang; Hee Yeol Kim; Ki Dong Yoo; Doo Soo Jeon; Wook-Sung Chung; Ki-Bae Seung

Stent length has been considered an important predictor of adverse events after percutaneous coronary intervention, even with the first-generation drug-eluting stents (DESs). The introduction of newer-generation DES has further reduced the rates of adverse clinical events such as restenosis, myocardial infarction, and stent thrombosis. The aim of this study was to compare the impact of stent length on the long-term clinical outcomes between first- and newer-generation DESs. The effects of stent length (≥32 vs <32 mm) on the clinical outcomes were evaluated in 8,445 patients who underwent percutaneous coronary intervention using either a first-generation DES (sirolimus- and paclitaxel-eluting stents, n = 6,334) or a newer-generation DES (everolimus- and zotarolimus-eluting stents, n = 2,111) from January 2004 to December 2009. The 3-year adverse outcomes (composite of all-cause death, nonfatal myocardial infarction, target vessel revascularization, and stent thrombosis) were compared using the inverse probability of treatment-weighted method according to the stent length. After adjustment for differences in the baseline risk factors, a stent length of ≥32 mm was significantly associated with higher cumulative rates of target vessel revascularization and stent thrombosis in the patients treated with a first-generation DES (adjusted hazard ratio 1.875, 95% confidence interval 1.531 to 2.297, p <0.001; adjusted hazard ratio 2.964, 95% confidence interval 1.270 to 6.917, p = 0.012), but it was not associated with the clinical outcomes in patients treated with a newer-generation DES. In conclusion, stent length might not be associated with long-term clinical outcomes in newer-generation DES era, whereas stent length might be associated with long-term clinical outcomes in the first-generation DESs.


American Journal of Cardiology | 2016

Impact of Percutaneous Coronary Intervention for Chronic Total Occlusion in Non–Infarct-Related Arteries in Patients With Acute Myocardial Infarction (from the COREA-AMI Registry)

Ik Jun Choi; Yoon-Seok Koh; Sungmin Lim; Eun Ho Choo; Jin Jin Kim; Byung-Hee Hwang; Tae-Hoon Kim; Suk Min Seo; Chan Joon Kim; Mahn-Won Park; Dong Il Shin; Yun-Seok Choi; Hun-Jun Park; Sung-Ho Her; Dong-Bin Kim; Chul Soo Park; Jong Min Lee; Keon Woong Moon; Kiyuk Chang; Hee Yeol Kim; Ki-Dong Yoo; Doo Soo Jeon; Wook-Sung Chung; Youngkeun Ahn; Myung Ho Jeong; Ki-Bae Seung; Pum-Joon Kim

Chronic total occlusion (CTO) in a non-infarct-related artery (IRA) is an independent predictor of clinical outcomes in patients with acute myocardial infarction (AMI). This study evaluated the impact of successful percutaneous coronary intervention (PCI) for CTO of a non-IRA on the long-term clinical outcomes in patients with AMI. A total of 4,748 patients with AMI were consecutively enrolled in the Convergent Registry of Catholic and Chonnam University for AMI registry from January 2004 to December 2009. We enrolled 324 patients with CTO in a non-IRA. To adjust for baseline differences, propensity matching (96 matched pairs) was used to compare successful PCI and occluded CTO for the treatment of CTO in non-IRA. The primary clinical end points were all-cause mortality and a composite of the major adverse cardiac events, including cardiac death, MI, stroke, and any revascularization during the 5-year follow-up. Patients who received successful PCI for CTO of non-IRA had lower rates of all-cause mortality (16.7% vs 32.3%, hazard ratio 0.459, 95% CI 0.251 to 0.841, p = 0.012) and major adverse cardiac events (21.9% vs 55.2%, hazard ratio 0.311, 95% CI 0.187 to 0.516, p <0.001) compared with occluded CTO group. Subgroup analyses revealed that successful PCI resulted in a better mortality rate in patients with normal renal function compared to patients with chronic kidney disease (p = 0.010). In conclusion, successful PCI for CTO of non-IRA is associated with improved long-term clinical outcomes in patients with AMI.


International Journal of Cardiology | 2014

Status of hypertension and coronary stenosis in asymptomatic type 2 diabetic patients: Analysis from Coronary Computed Tomographic Angiography Registry

Eun-Ho Choo; Jin-Jin Kim; Byung-Hee Hwang; Ik Jun Choi; Mineok Chang; Sungmin Lim; Yoon-Seok Koh; Hun Jun Park; Pum-Joon Kim; Seung Hwan Lee; Keon-Ho Yoon; Jung-Im Jung; Wook Sung Chung; Ki-Bae Seung; Jae-Hyung Cho; Kiyuk Chang

BACKGROUND Limited data exist regarding the prevalence of coronary artery disease (CAD) as well as clinical outcomes in asymptomatic diabetic patients with normotension, controlled hypertension, and uncontrolled hypertension. METHODS We enrolled 935 consecutive asymptomatic type 2 diabetic patients without known CAD. Coronary computed tomography angiography was used to evaluate the prevalence and severity of CAD. Blood pressure was measured at baseline. Patients were assigned to one of the three groups: normotension (n=314), controlled hypertension (systolic blood pressure (SBP)< 140 mm Hg with treatment, n=458), or uncontrolled hypertension (SBP ≥ 140 mm Hg with or without treatment, n=163). RESULTS Obstructive CAD (≥ 50% stenosis) increased from the prevalence in normotensive patients (33%) to that in patients with controlled (40%) or uncontrolled hypertension (52%) (p=0.003). The incidence of obstructive CAD in multivessel or left main CAD also increased across the three groups (13%, 21%, 32%, respectively, p<0.001). A multivariate logistic regression analysis showed that uncontrolled hypertension was an independent predictor of obstructive CAD (adjusted odds ratio, 2.13; 95% confidence interval (CI), 1.42 to 3.21, p<0.001). During a median follow-up of 3.1 years, uncontrolled hypertension was associated with increased risk of cardiac death or myocardial infarction compared to the risk in normotensive patients (hazard ratio, 6.11; 95% CI, 1.65 to 22.6, p=0.007). CONCLUSION In asymptomatic type 2 diabetic patients, uncontrolled hypertension was associated with increased risk of CAD and poor clinical outcomes.


International Heart Journal | 2015

Impact of Cystatin-C Level on the Prevalence and Angiographic Characteristics of Vasospastic Angina in Korean Patients

Su Nam Lee; Dong Il Shin; Mi-Hyang Jung; Ik Jun Choi; Suk Min Seo; Sung Ho Her; Pum-Joon Kim; Keon-Woong Moon; Ki-Dong Yoo; Sang Hong Baek; Ki-Bae Seung

Cystatin-C, a marker of mild renal dysfunction, has been reported to be associated with cardiovascular diseases including vasospastic angina (VSA). We aimed to investigate the impact of cystatin-C level on the prevalence and angiographic characteristics of VSA in Korean patients.A total of 549 patients in the VA-KOREA (Vasospastic Angina in KOREA) registry who underwent ergonovine provocation tests were consecutively enrolled. Estimated glomerular filtration rate (eGFR) and levels of serum creatinine (Cr) and cystatin-C were assessed before angiography.The patients were classified into two groups: the VSA group (n = 149, 27.1%) and the non-VSA group (n = 400). Although eGFR and Cr levels were similar between the two groups, the VSA group had a significantly higher level of cystatin-C (P < 0.05). A high level of cystatin-C (second tertile, hazard ratio 1.432; 95% confidence interval [1.1491.805]; P = 0.026, third tertile, 1.947 [1.132-2.719]; P = 0.003) and current smoking (2.710 [1.415-4.098]; P < 0.001) were independently associated with the prevalence of VSA. Furthermore, the highest level of cystatin-C (> 0.96 ng/mL) had a significant impact on the incidence of multivessel spasm (2.608 [1.061-4.596]; P = 0.037).A high level of cystatin-C was independently associated with the prevalence of VSA and with a high-risk type of VSA in Korean patients, suggesting that proactive investigation of VSA should be considered for patients with mild renal dysfunction indicated by elevated cystatin-C.


Diabetes Care | 2017

Computed Tomography Angiography Images of Coronary Artery Stenosis Provide a Better Prediction of Risk Than Traditional Risk Factors in Asymptomatic Individuals With Type 2 Diabetes: A Long-term Study of Clinical Outcomes

Kwan Yong Lee; Byung-Hee Hwang; Tae-Hoon Kim; Chan Jun Kim; Jin-Jin Kim; Eun-Ho Choo; Ik Jun Choi; Young Mee Choi; Ha-Wook Park; Yoon-Seok Koh; Pum-Joon Kim; Jong Min Lee; Mi-Jeong Kim; Doo Soo Jeon; Jae-Hyoung Cho; Jung Im Jung; Ki-Bae Seung; Kiyuk Chang

OBJECTIVE We investigated the efficacy of coronary computed tomography angiography (CCTA) in predicting the long-term risks in asymptomatic patients with type 2 diabetes and compared it with traditional risk factors. RESEARCH DESIGN AND METHODS We analyzed 933 patients with asymptomatic type 2 diabetes who underwent CCTA. Stenosis was considered obstructive (≥50%) in each coronary artery segment using CCTA. The extent and severity scores for coronary artery disease (CAD) were evaluated. The primary end point was major adverse cardiovascular events (MACE), including all-cause mortality, nonfatal myocardial infarction, and late coronary revascularization during a mean follow-up period of 5.5 ± 2.1 years. RESULTS Ninety-four patients with MACE exhibited obstructive CAD with a greater extent and higher severity scores (P < 0.001 for all). After adjusting for confounding risk factors, obstructive CAD remained an independent predictor of MACE (hazard ratio 3.11 [95% CI 2.00–4.86]; P < 0.001]). The performance of a risk prediction model based on C-statistics was significantly improved (C-index 0.788 [95% CI 0.747–0.829]; P = 0.0349) upon the addition of a finding of obstructive CAD using CCTA to traditional risk factors, including age, male, hypertension, hyperlipidemia, smoking, estimated glomerular filtration rate, and HbA1c. Both integrated discrimination improvement (IDI) and net reclassification improvement (NRI) analyses further supported this finding (IDI 0.046 [95% CI 0.020–0.072], P < 0.001, and NRI 0.55 [95% CI 0.343–0.757], P < 0.001). In contrast, the risk prediction power of the coronary artery calcium score remained unimproved (C-index 0.740, P = 0.547). CONCLUSIONS Based on our data, the addition of CCTA-detected obstructive CAD to models that include traditional risk factors improves the predictions of MACE in asymptomatic patients with type 2 diabetes.


Medicine | 2016

CYP2C19 loss-of-function alleles are not associated with clinical outcome of clopidogrel therapy in patients treated with newer-generation drug-eluting stents.

Ik Jun Choi; Yoon-Seok Koh; Mahn-Won Park; Sung Ho Her; Yun-Seok Choi; Chul-Soo Park; Hun-Jun Park; Pum-Joon Kim; Wook-Sung Chung; Ho-Sook Kim; Jae-Gook Shin; Ki-Bae Seung; Kiyuk Chang

AbstractCYP2C19 loss-of-function (LOF) alleles adversely affect clinical outcome of clopidogrel therapy. Recent introduction of a newer-generation drug-eluting stent (DES) has significantly reduced the occurrence of stent thrombosis.The aim of this study was to evaluate the impact of CYP2C19 LOF alleles on clinical outcome in patients treated with the newer-generation DES.The effects of CYP2C19 genotypes were evaluated on clinical outcome of clopidogrel therapy in 2062 patients treated with percutaneous coronary intervention using either first-generation DES (sirolimus- and paclitaxel-eluting stent, n = 1349) or newer-generation DES (everolimus- and zotarolimus-eluting stent, n = 713). The primary clinical outcome was major cardiac and cerebrovascular event (MACCE) including cardiac death, nonfatal myocardial infarction, stroke, and stent thrombosis during 1 year of follow-up.CYP2C19 LOF alleles were significantly associated with a higher risk of MACCE in patients treated with first-generation DES (hazard ratio [HR] 2.599, 95% confidence interval [CI] 1.047–6.453; P = 0.034). In contrast, CYP2C19 LOF alleles were not associated with primary outcome in newer-generation DES (HR 0.716, 95% CI 0.316–1.622; P = 0.522). In the further multivariate analysis, CYP2C19 LOF alleles were not associated with MACCE in patients receiving newer-generation DES (adjusted HR 0.540, 95% CI 0.226–1.291; P = 0.166), whereas they were demonstrated to be an independent risk factor for MACCE in those implanted with first-generation DES (adjusted HR 3.501, 95% CI 1.194–10.262; P = 0.022).In contradiction to their clinical impact in first-generation DES era, CYP2C19 LOF alleles may not affect clinical outcome of clopidogrel therapy in patients treated with newer-generation DES.


Yonsei Medical Journal | 2016

Association between the Red Cell Distribution Width and Vasospastic Angina in Korean Patients

Mi Hyang Jung; Dong Il Shin; Ik Jun Choi; Suk Min Seo; Sooa Choi; Mahn Won Park; Pum Joon Kim; Sang Hong Baek; Ki Bae Seung

Purpose The association between the red cell distribution width (RDW) and vasospastic angina (VSA) has not been elucidated. We investigated the association of the RDW with the incidence and angiographic subtypes of VSA in Korean patients. Materials and Methods A total of 460 patients who underwent intracoronary ergonovine provocation tests were consecutively enrolled and classified into two groups: the VSA group (n=147, 32.0%) and non-VSA group (n=313, 68.0%). The subjects were classified into 3 subgroups (tertiles) according to the baseline level of RDW assessed before the angiographic provocation test. Results The VSA group had a higher RDW than the non-VSA group (12.9±0.8% vs. 12.5±0.7%, p=0.013). The high RDW level demonstrated an independent association with the high incidence of VSA [second tertile: hazard ratio (HR) 1.96 (1.13–2.83), third tertile: HR 2.33 (1.22–3.47), all p<0.001]. Moreover, the highest RDW tertile level had a significant association with the prevalence of the mixed-type coronary spasm [HR 1.29 (1.03–1.59), p=0.037]. Conclusion The high level of RDW was significantly associated with the prevalence of VSA and the high-risk angiographic subtype of coronary spasm, suggesting that a proactive clinical investigation for VSA could be valuable in Korean patients with an elevated RDW.


Journal of Hypertension | 2016

PS 02-10 Relationship of brachial-ankle pulse wave velocity and coronary atherosclerosis in asymptomatics: Evaluation by coronary CT angiography

Jin-Jin Kim; Jaeho Byeon; Kwan Yong Lee; Tae-Hoon Kim; Ki-Bae Seung; Byung-Hee Hwang; Eun Ho Choo; Ik Jun Choi; Sungmin Lim; Chan Jun Kim; Kiyuk Chang

Objective: We investigated the association of arterial stiffness, assessed by pulse wave velocity (PWV) with the prevalence, extent, and severity of coronary atheroma burden using coronary computed tomography angiography (CCTA) in community-dwelling Korean adults without chest pain. Design and Method: We analyzed 749 individuals without known or suspected coronary artery disease (CAD) undergoing CCTA. Participants were divided into two groups according to the mean value of PWV: 1455 cm/sec. Obstructive CAD, as measured by CCTA, was defined as maximum intra-luminal stenosis ≥ 50%. We compared the prevalence, extent, and severity of coronary atheroma burden, including coronary artery calcium score (CACS), atheroma burden obstructive score (ABOS), segment involvement score (SIS), and segment stenosis score (SSS) between groups. Multivariable logistic regression analysis was also performed to identify independent predictors of CAD. Results: Individuals with higher PWV possessed higher obstructive CAD (p < 0.001). Higher PWV was associated with greater degrees of CACS, ABOS, SIS, and SSS on CT scans (p < 0.001 for all). Multivariable analyses adjusted for conventional cardiovascular risk factors, including age, sex, and diabetes mellitus revealed that higher PWV was an independent predictor of obstructive CAD (odds ratio 2.694, confidence intervals 1.382–5.252, p = 0.004). Conclusions: Arterial stiffness assessed by PWV was associated with higher prevalence, extent, and severity of coronary atherosclerosis as well as increased risk of obstructive CAD in asymptomatics. Figure. No caption available.


Journal of Hypertension | 2016

PS 02-24 INCREMENTAL IMPACT OF BLOOD PRESSURE ON CORONARY CALCIFICATION AND ATHEROSCLEROSIS IN ASYMPTOMATIC INDIVIDUALS: ANALYSIS FROM CORONARY COMPUTED TOMOGRAPHIC ANGIOGRAPHY REGISTRY

Ik Jun Choi; Byung-Hee Hwang; Suk Min Seo; Yoon-Seok Koh; Woo-Baek Chung; Hun-Jun Park; Pum-Joon Kim; Sang-Hyun Ihm; Kiyuk Chang; Doo-Soo Jeon; Wook-Sung Chung

Objective: The aim of this study was to assess the level of blood pressure on the extent and developmental pattern of coronary artery disease (CAD). Design and Method: A total of 2,676 self-referred asymptomatic individuals without known CAD who underwent 64-channel dual-source coronary computed tomography angiography (CCTA) between 2006 and 2010. The patients were divided into three groups based on their systolic blood pressure (group 1 <120mmHg, group 2 120∼139mmHg, and group 3 ≥140mmHg). We compared the coronary artery calcium score (CACS), atheroma burden obstructive score (ABOS), segment involvement score (SIS), and segment stenosis score (SSS). All-cause mortality during 3 years was also compared. Results: Patients with higher blood pressure possessed greater degree of CACS, ABOS, SIS, and SSS (p<0.001 for all) with associated with higher all-cause mortality (log rank, p = 0.002). Conclusions: In asymptomatic individuals, normal blood pressure is associated with a lower extent and severity of coronary calcium and atherosclerosis as well as risk of mortality.

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Ki-Bae Seung

Catholic University of Korea

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Kiyuk Chang

Catholic University of Korea

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Byung-Hee Hwang

Catholic University of Korea

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Sungmin Lim

Catholic University of Korea

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Pum-Joon Kim

Catholic University of Korea

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Yoon-Seok Koh

Catholic University of Korea

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Suk Min Seo

Catholic University of Korea

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Eun Ho Choo

Catholic University of Korea

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Hun-Jun Park

Catholic University of Korea

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Jin Jin Kim

Catholic University of Korea

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