Yeon Hyeon Choe

Sungkyunkwan University, Sŏul, Seoul, South Korea

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Publications (195)600.25 Total impact

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    ABSTRACT: Cross-sectional data suggest that the degree of coronary atherosclerosis is associated with aerobic fitness. However, there are limited longitudinal data addressing whether aerobic fitness is a predictor of coronary atherosclerosis progression. This study investigated whether peak oxygen consumption is related to a longitudinal increase in coronary calcium scores. Study subjects were voluntary participants in a health screening program who underwent a cardiopulmonary function test and repeated coronary calcium scoring. Individuals with clinical cardiovascular disease were excluded. The final sample included 4843 subjects with 14,856 records. The treadmill exercise test was performed using a modified Bruce protocol and Agatston coronary artery calcium (CAC) scores were measured using multi-detector CT. The mean age of the participants was 52 ± 6 years and 4.7 % were female. In a multi-level mixed effect regression model, increased CAC scores over time were significantly less likely in individuals with a higher VO2peak after adjusting for age, gender, hypertension, HbA1c, smoking status and LDL cholesterol levels (p < 0.001). Aerobic fitness has a protective effect on the progression of coronary atherosclerosis in an asymptomatic middle-aged population.
    Heart and Vessels 09/2015; DOI:10.1007/s00380-015-0745-2 · 2.07 Impact Factor
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    ABSTRACT: A new CT-based diagnostic method of protrusio acetabuli (PA) was introduced. However, prevalence of PA by this method and correlation between PA and other manifestations of Marfan syndrome (MFS) is unknown in Korean MFS patients. This study aimed to investigate the prevalence of PA diagnosed by a CT-based method in Korean patients with MFS, the association of PA with other manifestations of MFS, and the contribution of PA to MFS diagnosis. We retrospectively reviewed the records of 146 MFS patients with the presence of a causative FBN1 mutation and 146 age- and sex-matched controls from a single tertiary care center. All MFS patients underwent a complete assessment of criteria based on the revised Ghent nosology. PA was assessed quantitatively using a CT-based circle-wall distance (CWD) method. PA was diagnosed in 77.4% of patients in the MFS group and in 11.0% of the control group. CWD was significantly different between the two groups (1.50 mm vs. -0.64 mm, P<0.001). The presence of PA did not correlate with the presence of ectopia lentis, aortic root diameter, or history of aortic dissection. The presence of PA did not have a significant impact on the final diagnosis of MFS. Even though the presence of PA does not related to the cardinal clinical features of MFS or influence MFS diagnosis, its presence may be helpful for the suspicion of MFS when aortic dissection or aneurysm is found on CT angiography of the aorta because of the high frequency of PA in MFS patients.
    Journal of Korean medical science 09/2015; 30(9):1260-5. DOI:10.3346/jkms.2015.30.9.1260 · 1.27 Impact Factor
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    ABSTRACT: The aim of this study was to investigate whether noninvasive discrimination of chronic total occlusion (CTO), a complete interruption of coronary artery flow, and subtotal occlusion (STO), a functional total occlusion, is feasible using coronary computed tomography angiography (CTA). CTO and STO may be different in pathophysiology and clinical treatment strategy. We included 486 consecutive patients (median age 63 years, 82% male) who showed a total of 553 completely occluded coronary arteries in coronary CTA. The length of occlusion, side branches, shape of proximal stump, and collateral vessels were measured as anatomical findings. Transluminal attenuation gradient, which reflects intraluminal contrast kinetics and functional extent of collateral flow, was measured as a physiological surrogate. All patients were followed by invasive coronary angiography. Coronary arteries with CTO showed longer occlusion length (cutoff ≥15 mm), higher distal transluminal attenuation gradient (cutoff ≥-0.9 Hounsfield units [HU]/10 mm), more frequent side branches, blunted stump, cross-sectional calcification ≥50%, and collateral vessels compared with arteries with STO (p < 0.001, all). The combination of these findings could distinguish CTO from STO (c-statistics = 0.88 [95% confidence interval: 0.94 to 0.90], sensitivity 83%, specificity 77%, positive predictive value 55%, negative predictive value 93%; p < 0.001). Percutaneous coronary intervention (PCI) was attempted in 342 arteries and was successful in 279 arteries (82%). The computed tomography findings could predict the unsuccessful PCI (c-statistics = 0.70 [95% confidence interval: 0.65 to 0.75], sensitivity 63%, specificity 73%, positive predictive value 91%, negative predictive value 31%; p < 0.001). Noninvasive coronary CTA could discern CTO from STO, and also could predict the success of attempted PCI. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
    JACC. Cardiovascular Interventions 08/2015; 8(9):1143-53. DOI:10.1016/j.jcin.2015.03.042 · 7.35 Impact Factor
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    ABSTRACT: Because of frequent tuberculosis in patients with Takayasu arteritis (TA), a possible relationship between TA and tuberculosis has been proposed. However, there are no studies to date that have examined clinical manifestations in patients diagnosed with TA with or without tuberculosis. Two hundred sixty-seven patients were diagnosed with TA according to the 1990 American College of Rheumatology criteria between September 1994 and April 2014. Patients with TA were classified into groups with or without tuberculosis. Among the 267 patients with TA studied, 47 patients (17.7 %) who had a history of previous treatment of tuberculosis (34 patients), concurrent diagnosis of tuberculosis with TA (10 patients), or diagnosis of tuberculosis during the follow-up period for TA (3 patients) were included in the group with tuberculosis. The group with tuberculosis comprised of 33 patients (70.2 %) with pulmonary tuberculosis, 12 patients (25.5 %) with tuberculous lymphadenitis, and 2 patients (4.3 %) with tuberculosis of the skin and colon, respectively. Comorbid disease and patients' signs and symptoms were not significantly different between TA patients with and without tuberculosis. Additionally, the site of disease involvement in angiographic findings and distribution of angiographic type were similar between the two groups. In conclusion, tuberculosis including tuberculous lymphadenitis was frequently observed in patients with TA. Clinical features and angiographic findings in TA were not different according to the presence or absence of concomitant tuberculosis.
    Heart and Vessels 08/2015; DOI:10.1007/s00380-015-0731-8 · 2.07 Impact Factor
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    ABSTRACT: Apical hypertrophic cardiomyopathy (ApHCM) is thought to have a favourable clinical outcome, compared with other types of HCM. We sought to investigate the clinical and anatomical differences in cardiovascular imaging between ApHCM and non-ApHCM. A total of 350 patients diagnosed with HCM underwent cardiovascular magnetic resonance (CMR) and echocardiography. All enrolled subjects were prospectively followed up for adverse clinical outcomes. Eighty-five patients were classified as ApHCM. On CMR, the amount and proportion of late gadolinium enhancement (LGE) as well as left ventricular volumetric parameters were evaluated. Echocardiographic evaluations included diastolic function and global strain. Patients with ApHCM were less likely to present with history of syncope and have less frequency of family history of sudden cardiac death than those with non-ApHCM. Functional class was also more favourable in ApHCM [frequency of New York Heart Association (NYHA) class I; 89.4 vs. 66.8%, P < 0.001]. LGE was less frequently detected (87.1 vs. 93.9%, P = 0.04), and the amount of LGE was significantly smaller in ApHCM (7.0 ± 6.0 vs. 14.6 ± 10.5%, P < 0.001). The E/e' level and left atrial volume index were also lower in ApHCM patients (all P < 0.001). During follow-up, a composite of adverse clinical events including cardiac death, admission for heart failure, and cerebrovascular accident was higher in patients with ApHCM than those with non-ApHCM (P = 0.01). ApHCM showed a relatively small burden of myocardial fibrosis and less severe diastolic dysfunction and subsequently more favourable clinical manifestations in comparison with other HCMs. This may be one explanation of why most patients with ApHCM show a benign course of disease compared with non-ApHCM. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email:
    European Heart Journal Cardiovascular Imaging 08/2015; DOI:10.1093/ehjci/jev192 · 4.11 Impact Factor
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    ABSTRACT: Increased left ventricular (LV) mass is associated with adverse cardiovascular outcomes, and its accurate assessment is important. The aim of this study was to analyze the degree of difference among various methods of LV mass calculation based on transthoracic echocardiographic (TTE) measurements and cardiovascular magnetic resonance (CMR) measurements, especially in patients with aortic stenosis with varying degrees of LV hypertrophy (LVH). The mechanism underlying this disagreement was also investigated. Ninety-nine patients with moderate to severe aortic stenosis and 33 control subjects matched for age, sex, body weight, and height were enrolled in this prospective observational cohort study. All patients underwent TTE and CMR imaging. LV mass index (LVMI) was calculated using three formulas on the basis of TTE measurements (the Penn-cube, American Society of Echocardiography [ASE], and Teichholz methods) and compared with measurements obtained using CMR, the reference method. Although all methods calculated using TTE measurements showed good correlations with CMR measurements, LVMI measured using the Penn-cube and ASE methods tended to be larger than LVMI measured using CMR (difference in LVMI by the Penn-cube and ASE methods, 59.3 ± 29.7 and 30.6 ± 22.3 g/m(2), respectively). This tendency decreased with the Teichholz method (difference in LVMI by the Teichholz method, 22.9 ± 19.1 g/m(2)). The degree of LVMI overestimation was significantly different among the three methods (P < .001 by one-way analysis of variance), which was more significant in patients with LVH, especially with the Penn-cube method (differences between CMR and TTE measurements in patients with aortic stenosis and LVH, 66.3 ± 34.8 vs 31.2 ± 26.6 vs 15.5 ± 20.9 g/m(2) for the Penn-cube, ASE, and Teichholz methods, respectively; P < .001 with post hoc Tukey analysis). There was a good correlation between LVMI and LV diameter-to-length ratio (r = 0.468, P < .001), which suggested that the left ventricle takes on a more globular shape with the increase of LVMI, resulting in a significant deviation from the basic assumptions on which the Penn-cube and ASE methods were built. Current methods of calculating LVMI from echocardiographic measurements carry a tendency to measure LVMI larger than methods based on CMR measurements, which was more significant in patients with LVH. The change of the left ventricle's shape with LVH may be a plausible explanation for this, and a correction method may be needed when calculating LVMI from echocardiographic measurements, especially in patients with LVH and smaller body size. Copyright © 2015 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.
    Journal of the American Society of Echocardiography: official publication of the American Society of Echocardiography 07/2015; DOI:10.1016/j.echo.2015.06.009 · 4.06 Impact Factor
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    ABSTRACT: The purpose of this study was to evaluate differences in the diagnostic accuracy of absolute and relative territorial myocardial blood flow (MBF) derived from stress dynamic CT myocardial perfusion imaging (MPI) for the detection of significant coronary artery stenosis. Dynamic CT MPI and coronary CT angiography (CTA) datasets from a multicenter registry of 137 patients (mean age, 60.9 ± 8.4 years; 88 men) with suspected or known coronary artery disease were retrospectively analyzed. For each coronary territory, absolute MBF and the MBF relative to remote myocardium (MBF ratio) were calculated. Coronary CTA datasets were visually assessed for significant stenosis (≥ 50% luminal narrowing) in consensus by two observers. Significant stenosis was detected in 137 of 411 (33.3%) vessels. Mean absolute MBF and MBF ratio were statistically significantly lower in territories supplied by arteries with stenosis (80.7 ± 33.7 vs 140.0 ± 38.4 mL/100 mL/min and 0.52 vs 0.89, respectively; both p < 0.0001). ROC analysis showed better discrimination by MBF ratio than by absolute MBF (AUC, 0.925 vs 0.882; p = 0.0022) and increased sensitivity (90.7% vs 82.4%; p < 0.04) and specificity (93.1% vs 80.5%; p < 0.03) for MBF ratio and absolute MBF cutoff values of 0.71 or less and 103 mL/100 mL/min or less, respectively. In stress dynamic CT MPI, relative MBF provides superior diagnostic accuracy compared with absolute territorial MBF values for coronary CTA-detected significant coronary artery stenosis.
    American Journal of Roentgenology 07/2015; 205(1):W67-W72. DOI:10.2214/AJR.14.14087 · 2.73 Impact Factor
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    ABSTRACT: To assess the impact of left ventricular (LV) diastolic dysfunction on left atrial (LA) phasic volume and function using dual-source CT (DSCT) and to find a viable alternative prognostic parameter of CT for LV diastolic dysfunction through quantitative evaluation of LA phasic volume and function in patients with LV diastolic dysfunction. Seventy-seven patients were examined using DSCT and Doppler echocardiography on the same day. Reservoir, conduit, and contractile function of LA were evaluated by measuring LA volume (LAV) during different cardiac phases and all parameters were normalized to body surface area (BSA). Patients were divided into four groups (normal, impaired relaxation, pseudonormal, and restrictive LV diastolic filling) according to echocardiographic findings. The LA phasic volume and function in different stages of LV diastolic function was compared using one-way ANOVA analysis. The correlations between indexed volume of LA (LAVi) and diastolic function in different stages of LV were evaluated using Spearman correlation analysis. LA ejection fraction (LAEF), LA contraction, reservoir, and conduit function in patients in impaired relaxation group were not different from those in the normal group, but they were lower in patients in the pseudonormal and restrictive LV diastolic dysfunction groups (P < 0.05). For LA conduit function, there were no significant differences between the patients in the pseudonormal group and restrictive filling group (P = 0.195). There was a strong correlation between the indexed maximal left atrial volume (LAVmax, r = 0.85, P < 0.001), minimal left atrial volume (LAVmin, r = 0.91, P < 0.001), left atrial volume at the onset of P wave (LAVp, r = 0.84, P < 0.001), and different stages of LV diastolic function. The LAVi increased as the severity of LV diastolic dysfunction increased. LA remodeling takes place in patients with LV diastolic dysfunction. At the same time, LA phasic volume and function parameters evaluated by DSCT indicated the severity of the LV diastolic dysfunction. Quantitative analysis of LA phasic volume and function parameters using DSCT could be a viable alternative prognostic parameter of LV diastolic function.
    PLoS ONE 05/2015; 10(5):e0127289. DOI:10.1371/journal.pone.0127289 · 3.23 Impact Factor
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    ABSTRACT: Because Takayasu arteritis (TA) predominantly affects females, few data regarding gender differences have been reported. The aim of the present study is to describe clinical features and angiographic findings of patients with TA according to gender. According to the 1990 American College of Rheumatology criteria, 294 patients were diagnosed with TA between September 1994 and April 2014 at a single tertiary hospital. We reviewed clinical, laboratory, and radiologic data at the time of diagnosis. Among the 294 patients studied, 257 (87.4%) were female (male:female ratio=1:6.9). Female patients had a higher tendency to exhibit blood pressure differences between arms (p=0.595) and a weak pulse at the brachial artery (p=0.063). In male patients, we observed higher serum creatinine levels (p=0.038) and hypertension more frequently (p=0.061) than in females. Females exhibited more common lesions in the thoracic aorta and its branches, while males had more frequent lesions in the abdominal aorta and its branches. An analysis of angiographic classification according to the International TA Conference in Tokyo 1994 classification revealed that male patients had a higher incidence of type IV and females showed a higher incidence of types I, IIa, and IIb. Female patients with TA have more frequent involvement of the thoracic aorta and its branches, whereas involvement of the abdominal aorta and its branches is more common in males. Considering these gender-specific differences, adjustment of diagnostic criteria for TA according to gender may be necessary.
    Clinical and experimental rheumatology 05/2015; 33(2 Suppl 89):132-7. · 2.72 Impact Factor
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    ABSTRACT: Despite technical simplicity and the low cost of brachial-ankle pulse wave velocity (BA-PWV), its use has been hampered by a lack of data supporting its usefulness and reliability. The aim of this study was to evaluate the usefulness of BA-PWV to measure aortic stiffness in comparison to using cardiovascular magnetic resonance (CMR). A total of 124 participants without cardiovascular risk factors volunteered for this study. BA-PWV was measured using a vascular testing device. On the same day, using CMR, cross-sectional areas for distensibility and average blood flow were measured at four aortic levels: the ascending, upper thoracic descending, lower thoracic descending, and abdominal aorta. Compared to PWV measured by CMR, BA-PWV values were significantly higher and the differences therein were similar in all age groups (all p<0.001). There was a significant correlation between BA-PWV and PWV by CMR (r=0.697, p<0.001). Both BA-PWV and PWV by CMR were significantly and positively associated with age (r=0.652 and 0.724, p<0.001). The reciprocal of aortic distensibility also demonstrated a statistically significant positive correlation with BA-PWV (r=0.583 to 0.673, all p<0.001). BA-PWV was well correlated with central aortic PWV and distensibility, as measured by CMR, regardless of age and sex.
    Yonsei medical journal 05/2015; 56(3):617-24. DOI:10.3349/ymj.2015.56.3.617 · 1.29 Impact Factor
  • Journal of thoracic imaging 04/2015; 30(3). DOI:10.1097/RTI.0000000000000156 · 1.74 Impact Factor
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    ABSTRACT: It is uncertain that atorvastatin pretreatment can reduce myocardial damage in patients undergoing primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI). The aim of this study was to investigate the effects of atorvastatin pretreatment on infarct size measured by contrast-enhanced magnetic resonance imaging (CE-MRI) in STEMI patients. Patients undergoing primary PCI for STEMI within 12 hr after symptom onset were randomized to an atorvastatin group (n=30, 80 mg before PCI and for 5 days after PCI) or a control group (n=37, 10 mg daily after PCI). The primary end point was infarct size evaluated as the volume of delayed hyperenhancement by CE-MRI within 14 days after the index event. The median infarct size was 19% (IQR 11.1%-31.4%) in the atorvastatin group vs. 16.3% (7.2%-27.2%) in the control group (P=0.27). The myocardial salvage index (37.1% [26.9%-58.7%] vs. 46.9% [39.9-52.4], P=0.46) and area of microvascular obstruction (1.1% [0%-2.0%] vs. 0.7% [0%-1.8%], P=0.37) did not differ significantly between the groups. Frequency of the hemorrhagic and transmural infarctions was not significantly different in the 2 groups. Pretreatment with a high-dose atorvastatin followed by further treatment for 5 days in STEMI patients undergoing primary PCI failed to reduce the extent of myocardial damage or improve myocardial salvage. Graphical Abstract
    Journal of Korean medical science 04/2015; 30(4):435-41. DOI:10.3346/jkms.2015.30.4.435 · 1.27 Impact Factor
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    ABSTRACT: Background: Although left ventricular hypertrophy (LVH) and remodeling is associated with cardiac mortality and morbidity, little is known about the impact of gender on the ventricular response in aortic stenosis (AS) patients. This study aimed to analyze the differential effect of gender on ventricular remodeling in moderate to severe AS patients. Methods and results: A total of 118 consecutive patients (67±9 years; 63 males) with moderate or severe AS (severe 81.4%) underwent transthoracic echocardiography and cardiovascular magnetic resonance (CMR) within a 1-month period in this two-center prospective registry. The pattern of LV remodeling was assessed using the LV mass index (LVMI) and LV remodeling index (LVRI; LV mass/LV end-diastolic volume) by CMR. Although there were no differences in AS severity parameters nor baseline characteristics between genders, males showed a significantly higher LVMI (102.6±29.1 g/m2 vs. 86.1±29.2 g/m2, p=0.003) and LVRI (1.1±0.2 vs. 1.0±0.3, p=0.018), regardless of AS severity. The LVMI was significantly associated with aortic valve area (AVA) index and valvuloarterial impedance in females, whereas it was not in males, resulting in significant interaction between genders (PInteraction=0.007/0.014 for AVA index/valvuloarterial impedance, respectively). Similarly, the LVRI also showed a significantly different association between male and female subjects with the change in AS severity parameters (PInteraction=0.033/<0.001/0.029 for AVA index/transaortic mean pressure gradient/valvuloarterial impedance, respectively). Conclusion: Males are associated with greater degree of LVH and higher LVRI compared to females at moderate to severe AS. However, females showed a more exaggerated LV remodeling response, with increased severity of AS and hemodynamic loads, than males.
    PLoS ONE 03/2015; 10(3):e0121684. DOI:10.1371/journal.pone.0121684 · 3.23 Impact Factor
  • Journal of the American College of Cardiology 03/2015; 65(10):A1176. DOI:10.1016/S0735-1097(15)61176-7 · 16.50 Impact Factor
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    ABSTRACT: The appropriate indication for coronary computed tomographic angiography (CTA) as a part of preoperative evaluation has not been defined yet. We investigated the value of coronary CTA in patients undergoing noncardiac surgery. We included 844 patients (median age, 67 years; male sex, 62%) who underwent coronary CTA for screening of coronary artery disease before noncardiac surgery. Clinically determined revised cardiac risk index were compared with the extent and severity of coronary artery disease assessed by coronary CTA. Perioperative major cardiac event (PMCE), defined as cardiac death, myocardial infarction, or pulmonary edema within postoperative 30 days, developed in 25 patients (3.0%). Significant coronary CTA finding was defined as >3 any lesions with ≥1 (diameter stenosis ≥70%) stenosis based on the relationship between the severity of coronary artery disease and PMCE risk. The risk of PMCE was 14.0% in patients with significant CTA findings, whereas 2.2% of patients without significant CTA findings regardless of revised cardiac risk index score. The predictive performance of revised cardiac risk index could be improved significantly after addition of significant coronary CTA findings (c-statistics=0.631 versus 0.757; net reclassification improvement=0.923; integrated discrimination improvement=0.051). On the basis of revised cardiac risk index and coronary CTA, the risk of PMCE could be estimated with sensitivity, specificity, positive predictive value, and negative predictive value of 76%, 73%, 8%, and 99%, respectively. Addition of coronary CTA to clinical risk improved perioperative risk stratification. Absence of significant coronary CTA findings conferred low PMCE risk with high specificity and negative predictive value regardless of clinical risk. Coronary CTA may improve perioperative risk stratification in patients undergoing noncardiac surgery. © 2015 American Heart Association, Inc.
    Circulation Cardiovascular Imaging 03/2015; 8(3). DOI:10.1161/CIRCIMAGING.114.002582 · 5.32 Impact Factor
  • Journal of the American College of Cardiology 03/2015; 65(10):A1269. DOI:10.1016/S0735-1097(15)61269-4 · 16.50 Impact Factor
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    Yeonu Choi · Yeon Hyeon Choe · Sung Mok Kim · Sang-Chol Lee · Sung-A Chang
    Journal of Cardiovascular Magnetic Resonance 02/2015; 17(1). DOI:10.1186/1532-429X-17-S1-P301 · 4.56 Impact Factor
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    Journal of Cardiovascular Magnetic Resonance 02/2015; 17(1). DOI:10.1186/1532-429X-17-S1-P278 · 4.56 Impact Factor
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    ABSTRACT: In the effects of postconditioning on myocardial reperfusion in patients with ST-segment elevation myocardial infarction (POST) trial, ischemic postconditioning did not improve myocardial reperfusion in 700 patients with STEMI undergoing primary PCI. However, the impact of postconditioning on myocardial salvage and infarct size still needs to be addressed. The aim of this study was to investigate the effect of ischemic postconditioning on myocardial salvage using cardiac magnetic resonance (CMR) in patients with STEMI undergoing primary PCI. For the CMR substudy, a total of 111 patients was analyzed, 56 in the postconditioning group and 55 undergoing conventional primary PCI in the control group. Postconditioning was performed immediately after restoration of coronary flow by four cycles of 1-min balloon occlusion separated by 1 min of deflation. The primary end point was myocardial salvage measured by CMR 3 days after the index event. The myocardial salvage index was not improved by ischemic postconditioning compared with conventional PCI (46.3 ± 18.5 vs. 45.7 ± 20.5 %, p = 0.86). The infarct size was not significantly different between the two groups (18.8 ± 10.3 vs. 20.2 ± 11.0 %, p = 0.52). Moreover, there was no significant difference in the rates of microvascular obstruction or hemorrhagic infarction between the groups. CMR study demonstrated that ischemic postconditioning during primary PCI in STEMI patients did not improve myocardial salvage or reduce infarct size. These findings further support the results of the POST trial which showed no benefit of ischemic postconditioning as an adjunctive treatment of primary PCI.
    The International Journal of Cardiovascular Imaging 01/2015; 31(3). DOI:10.1007/s10554-015-0589-y · 1.81 Impact Factor
  • Sung Mok Kim · Young Kwon Cho · Yeon Hyeon Choe
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    ABSTRACT: The aim of this study was to evaluate the image quality and radiation dose in adenosine-stress dynamic myocardial CT perfusion (CTP) imaging using different tube voltages, tube current settings, and contrast materials containing different iodine concentrations in subjects with normal body mass indices (BMI). We included 92 patients (BMI range, 18.5-24.8) who underwent dynamic CTP for the evaluation of coronary artery disease using a 128-slice dual-source computed tomography. The protocols employed the following dynamic scan parameters: protocol I with 100 kV, fixed tube current (FTC), and medium-concentration contrast material (MC, 350 mg iodine/mL); protocol II with 100 kV, automatic tube current modulation (ATCM), and MC; protocol III with 100 kV, ATCM, and high-concentration contrast material (HC, 400 mg iodine/mL); protocol IV with 80 kV, adopted FTC, and HC. Subjective image quality on a 1-3 point scale and objective image quality with respect to the contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR) were assessed. Protocol IV showed higher CNR and SNR than the other protocols (P < 0.01), while the CNR and SNR values did not significantly differ among the other three protocols. There was no significant difference in subjective image quality among the protocols. The radiation dose in protocol IV was the lowest among the protocols (P < 0.01), while protocol IV resulted in a 54 % overall reduction in mean effective radiation dose compared with protocol I. Dynamic myocardial CTP performed at 80 kV with adapted FTC provided high CNR and SNR while preserving subjective image quality and reducing radiation exposure.
    The International Journal of Cardiovascular Imaging 08/2014; 30(2). DOI:10.1007/s10554-014-0524-7 · 1.81 Impact Factor

Publication Stats

2k Citations
600.25 Total Impact Points


  • 1998–2015
    • Sungkyunkwan University
      • • Department of Radiology
      • • School of Medicine
      • • Samsung Medical Center
      Sŏul, Seoul, South Korea
  • 1997–2015
    • Samsung Medical Center
      • • Department of Cardiology
      • • Department of Radiology
      • • Department of Pediatrics
      Sŏul, Seoul, South Korea
  • 2014
    • Seoul National University Bundang Hospital
      • Cardiovascular Center
      Sŏul, Seoul, South Korea
  • 2008
    • Chonbuk National University
      Tsiuentcheou, Jeollabuk-do, South Korea
  • 1994
    • Sejong General Hospital
      Bucheon, Gyeonggi Province, South Korea