Yuichi Ozaki

Wakayama Medical University, Wakayama, Wakayama, Japan

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Publications (44)237.75 Total impact

  • Yuichi Ozaki · Toshio Imanishi · Takashi Akasaka
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    ABSTRACT: Peripheral artery disease (PAD) is an inflammatory disease caused by atherosclerosis. It has been demonstrated that PAD is related to chronic inflammation. While conventional risk factors lead to the pathogenesis and progression of PAD, the role of novel inflammatory biomarkers in relation to PAD is being increasingly recognized. The novel biomarkers for PAD may allow for earlier screening and detection, suppression of disease progression, and development of new therapeutic approaches. In this review, inflammatory biomarkers that should be contributory to diagnosis, prognosis, and avenues for therapeutic challenges in PAD are summarized.
    Current Medicinal Chemistry 06/2015; · 3.85 Impact Factor
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    ABSTRACT: Previous studies have suggested that vasa vasorum (VV) is associated with plaque progression and vulnerability. The aim of this study was to investigate the relationship between coronary neovascularization structures and plaque characteristics. We included 53 patients who underwent optical coherence tomography to observe the proximal left anterior descending coronary artery. Patients were classified into 5 groups according to lesion characteristics: normal; fibrous plaque (FP); fibroatheroma (FA); plaque rupture (PR); and fibrocalcific plaque (FC). We defined signal-poor tubuloluminal structures recognized in cross-sectional and longitudinal profiles located in adventitial layer as VV, and within plaque as intraplaque neovessels. Two types of longitudinal microvascular structure (external running and internal running) and a particular type of intraplaque neovessels (a coral tree pattern) were noted. All VV and intraplaque neovessels were manually segmented followed by quantification with Simpson method. Among the groups, there was significant difference (expressed as median [interquartile range (IQR)]) in VV volume (normal: 0.329 [IQR: 0.209 to 0.361] mm(3), FP: 0.433 [IQR: 0.297 to 0.706] mm(3), FA: 0.288 [IQR: 0.113 to 0.364] mm(3), PR: 0.160 [IQR: 0.141 to 0.193] mm(3), and FC: 0.106 [IQR: 0.053 to 0.165] mm(3); p = 0.003) and intraplaque neovessels volume (normal: 0.00 [IQR: 0.00 to 0.00] mm(3), FP: 0.00 [IQR: 0.00 to 0.00] mm(3), FA: 0.028 [IQR: 0.019 to 0.041] mm(3), PR: 0.035 [IQR: 0.026 to 0.042] mm(3), and FC: 0.010 [IQR: 0.005 to 0.014] mm(3); p < 0.001). Significant differences were observed in the prevalence of the internal running (normal: 0.0%, FP: 28.6%, FA: 40.0%, PR: 70.0%, and FC: 40.0%; p = 0.032) and the coral tree pattern (normal: 0.0%, FP: 7.1%, FA: 40.0%, PR: 80.0%, and FC: 10.0%; p < 0.01). The VV volume correlated with fibrous plaque volume (r = 0.71; p < 0.01). VV increase with fibrous plaque volume and intraplaque neovessels with particular structures are associated with plaque vulnerability. Imaging for microvasculature could become a new window for plaque vulnerability. Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
    Journal of the American College of Cardiology 06/2015; 65(23):2469-2477. DOI:10.1016/j.jacc.2015.04.020 · 15.34 Impact Factor
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    ABSTRACT: The detailed mechanism of plaque stabilization by statin therapy is not fully understood.Objectives The aim of this study was to assess the effect of lipid-lowering therapy with 20 mg/day of atorvastatin versus 5 mg/day of atorvastatin on fibrous cap thickness in coronary atherosclerotic plaques by using optical coherence tomography (OCT).Methods Seventy patients with unstable angina pectoris and untreated dyslipidemia were randomized to either 20 mg/day or 5 mg/day of atorvastatin therapy. OCT was performed to assess intermediate nonculprit lesions at baseline and 12-month follow-up.ResultsSerum low-density lipoprotein cholesterol level was significantly lower during therapy with 20 mg/day compared with 5 mg/day of atorvastatin (69 mg/dl vs. 78 mg/dl; p = 0.039). The increase in fibrous cap thickness was significantly greater with 20 mg/day compared with 5 mg/day of atorvastatin (69% vs. 17%; p < 0.001). The increase in fibrous cap thickness correlated with the decrease in serum levels of low-density lipoprotein cholesterol (R = −0.450; p < 0.001), malondialdehyde-modified low-density lipoprotein (R = −0.283; p = 0.029), high-sensitivity C-reactive protein (R = −0.276; p = 0.033), and matrix metalloproteinase-9 (R = −0.502; p < 0.001), and the decrease in grade of OCT-derived macrophages (R = −0.415; p = 0.003).Conclusions Atorvastatin therapy at 20 mg/day provided a greater increase in fibrous cap thickness in coronary plaques compared with 5 mg/day of atorvastatin. The increase of fibrous cap was associated with the decrease in serum atherogenic lipoproteins and inflammatory biomarkers during atorvastatin therapy. (Effect of Atorvastatin Therapy on Fibrous Cap Thickness in Coronary Atherosclerotic Plaque as Assessed by Optical Coherence Tomography: The EASY-FIT Study; NCT00700037)
    Journal of the American College of Cardiology 11/2014; 64(21). DOI:10.1016/j.jacc.2014.08.045 · 15.34 Impact Factor
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    ABSTRACT: Background:A strategy of deferred percutaneous coronary intervention for coronary stenosis with fractional flow reserve (FFR) 0.75-0.80, termed the gray zone, remains a matter of debate. The aim of this study was to assess the safety of deferring revascularization for patients with FFR 0.75-0.80 compared with those with FFR >0.80.Methods and Results:We assessed 3-year clinical outcome in 150 patients with angiographically intermediate stenosis who had revascularization deferred on the basis of FFR ≥0.75 (FFR 0.75-0.80, n=56; FFR >0.80, n=94). Target vessel failure (TVF), defined as a composite of cardiac death, target vessel-related myocardial infarction (MI), and ischemia-driven target vessel revascularization (TVR) was evaluated during follow-up. Cardiac death was observed in 1 patient with FFR 0.75-0.80. There was no target vessel-related MI in either group. The incidence of ischemia-driven TVR was higher in patients with FFR 0.75-0.80 than in those with FFR >0.80 (14% vs. 3%, P=0.020). TVF-free survival was significantly worse for the patients with FFR 0.75-0.80 than those with FFR >0.80 (hazard ratio, 5.2; 95% confidence intervals: 1.4-19.5; P=0.015).Conclusions:Patients with FFR 0.75-0.80 were at higher risk of TVF mainly due to TVR than those with FFR >0.80.
    Circulation Journal 11/2014; 79(1). DOI:10.1253/circj.CJ-14-0671 · 3.69 Impact Factor
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    ABSTRACT: Objectives: The aim of this study was to investigate the impact of myocardial area supplied by the coronary artery on fractional flow reserve (FFR). Background: Various factors other than the degree of epicardial stenosis influence the physiological significance of a coronary artery stenosis. Methods: A total of 296 coronary lesions in 217 patients were analyzed by quantitative coronary angiography and FFR. Myocardial area supplied by the coronary artery distal to the stenosis was evaluated by angiography using a modified version of the Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease (APPROACH) score. Results: Percent diameter stenosis of the coronary lesion was 57 ± 15 % (mean ± standard deviation). FFR <0.80 was seen in 132 (45%) lesions. FFR was significantly correlated with minimum lumen diameter (r = 0.584, p <0.001), percent diameter stenosis (r = -0.565, p <0.001), lesion length (r = -0.306, p <0.001), and myocardial supply area (r = -0.504, p <0.001). Multivariate logistic analysis demonstrated that minimum lumen diameter (odds ratio [OR] = 0.031, 95% confidence interval [CI] = 0.013 - 0.076, p <0.001), lesion length (OR = 1.038, 95% CI = 1.009 - 1.069, p = 0.001), and myocardial supply area (OR = 1.113, 95% CI = 1.079 - 1.147, p <0.001) were independent determinants for FFR <0.80. Conclusions: FFR, which is the index of physiological significance of coronary artery stenosis, is influenced by myocardial supply area distal to the stenosis as well as by its own minimal lumen diameter and lesion length. © 2013 Wiley Periodicals, Inc.
    Catheterization and Cardiovascular Interventions 09/2014; 84(3). DOI:10.1002/ccd.25300 · 2.40 Impact Factor
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    ABSTRACT: Autopsy studies have reported that rupture of a thin-cap fibroatheroma and subsequent thrombus formation is the major mechanism leading to acute coronary syndrome (ACS). However, it is not clear why only some plaque ruptures lead to ACS. Optical coherence tomography (OCT) is a high-resolution imaging modality which is capable of investigating detailed coronary plaque morphology in vivo. The objective of this study was to determine whether ruptured plaque morphology assessed by OCT differs between asymptomatic coronary artery disease (CAD) and non-ST elevation acute coronary syndrome (NSTEACS).
    Atherosclerosis 06/2014; 235(2):532-537. DOI:10.1016/j.atherosclerosis.2014.05.920 · 3.97 Impact Factor
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    ABSTRACT: Objective Although monocytes appear to be actively involved in the onset of acute coronary syndrome (ACS), they are heterogenous in human peripheral blood. How up-regulation of monocyte subsets leads to coronary plaque rupture followed by thrombus formation remains unclear. Recent studies have shown that P-selectin glycoprotein ligand-1 (PSGL-1) is involved in monocyte activation in patients with thrombus formation. We therefore investigated the relationship between the expression of PSGL-1 on monocyte subsets and thrombus formation using frequency-domain optical coherence tomography (FD-OCT) in patients with ACS. Methods We enrolled a total of 100 individuals in this study: patients with acute myocardial infarction (AMI, n = 25), unstable angina pectoris (UAP, n = 20), or stable angina pectoris (n = 35) who underwent coronary angiography, and control subjects (n = 20). Three monocyte subsets (CD14++CD16−, CD14++CD16+, and CD14+CD16+) and the expression of PSGL-1 were measured by flow cytometry. In patients with AMI and UAP, FD-OCT was performed before percutaneous coronary intervention. Results Circulating peripheral CD14++CD16+ monocytes expressed PSGL-1 more frequently than CD14++CD16− and CD14+CD16+ monocytes in patients with ACS. The expression of PSGL-1 on circulating peripheral CD14++CD16+ monocytes was significantly elevated in patients with AMI compared with the other 3 groups. Moreover, the expression levels of PSGL-1 on CD14++CD16+ monocytes were significantly higher in patients with plaque rupture or intracoronary thrombus assessed by FD-OCT. Conclusion Up-regulation of PSGL-1 on CD14++CD16+ monocytes may be a crucial role in plaque rupture and thrombus formation.
    Atherosclerosis 04/2014; 233(2):697–703. DOI:10.1016/j.atherosclerosis.2013.12.052 · 3.99 Impact Factor
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    ABSTRACT: Some patients with acute myocardial infarction (AMI) have a poor prognosis due to left ventricular remodeling (LVR), resulting in the recurrence of congestive heart failure even when therapy with angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin II type 1 receptor blockers (ARBs) has been initiated. We investigated the effect of early administration of the direct renin inhibitor (DRI) aliskiren in combination with an ACEI or an ARB on LVR using cardiac magnetic resonance (CMR) imaging in patients with AMI.Twenty-one consecutive patients were treated with an ACEI or an ARB (non-DRI group), and another 21 consecutive patients received aliskiren 150 mg/day combined with an ACEI or an ARB (DRI group). CMR imaging was performed 7 days after AMI and 10 months later.CMR imaging revealed no significant changes in LV end-systolic volume, LV end-diastolic volume, or LV ejection fraction between the patients with and without DRI aliskiren. In the DRI group, plasma renin activity was signifi cantly lower in both the acute and chronic phases; however, aldosterone levels were significantly lower in the acute but not the chronic phase.A low dose of aliskiren may be insufficient to maintain suppression of aldosterone under current standard therapies with an ACEI or an ARB and β-blocker in patients with primary AMI, and results in no attenuation of LVR.
    International Heart Journal 01/2014; DOI:10.1536/ihj.13-212 · 1.13 Impact Factor
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    ABSTRACT: Background: It remains unclear whether glycemic fluctuation immediately after acute myocardial infarction (AMI) can affect myocardial damage. This study investigated the impact of glucose fluctuation on myocardial salvage following successful recanalization of primary AMI. Methods and Results: A total of 36 consecutive patients with AMI were studied. Glycemic variability, as indicated by the mean amplitude of glycemic excursion (MAGE), was measured on a continuous glucose monitoring system. Three subsets (CD14(+)CD16(-), CD14(++)CD16(+) and CD14(+-)CD16(+)) were measured on flow cytometry 1, 2, 3, 4 and 5 days after AMI onset. A 2-h oral glucose test was performed in 23 patients who had no previous diagnosis of diabetes and/or glycated hemoglobin <6.5%, after the onset of AMI at 2 weeks. Plasma active glucagon-like peptide (GLP)-1 level was measured in each sample. The extent of myocardial salvage 7 days after AMI was evaluated on cardiovascular magnetic resonance imaging. MAGE and the peak CD14(+)CD16(-) monocyte level were significantly negatively correlated with myocardial salvage index (MSI). MAGE was significantly correlated with peak CD14(+)CD16(-) monocyte level. Of interest, plasma GLP-1 level was significantly positively correlated with MSI and significantly negatively correlated with MAGE. Conclusions: Glucose fluctuations during the acute phase of AMI affect MSI, indicating that manipulation of glucose variability from peak to nadir might be a potential therapeutic target for salvaging ischemic damage.
    Circulation Journal 11/2013; 78(1). DOI:10.1253/circj.CJ-13-0723 · 3.69 Impact Factor
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    Journal of the American College of Cardiology 10/2013; 62(18). DOI:10.1016/j.jacc.2013.08.1323 · 15.34 Impact Factor
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    Journal of the American College of Cardiology 10/2013; 62(18). DOI:10.1016/j.jacc.2013.08.1358 · 15.34 Impact Factor
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    ABSTRACT: Histopathological studies have reported that optical coherence tomography (OCT) can accurately detect fibroatheroma that is involved in not only culprit lesion of acute coronary syndrome but also no-reflow phenomenon after percutaneous coronary intervention. Studies have demonstrated superiority of OCT in plaque characterization and interruption of arterial wall component. At current, multidetector computed tomography (MDCT) and virtual histology intravascular ultrasound (VH-IVUS) are considered as alternative imaging devices for coronary plaque characterization. This study aimed to compare the diagnostic accuracy for detecting fibroatheroma between MDCT and VH-IVUS using OCT as the reference standard. Forty-three lesions from 27 patients assessed by MDCT, VH-IVUS, and OCT were included in this study. Fibroatheroma was defined by OCT as a signal-poor region with a fast signal drop-off and little or no signal backscattering within the lesion. From 43 lesions, OCT revealed 21 fibroatheromas. Ring-like sign assessed by MDCT and positive remodeling assessed by IVUS were more frequently observed in OCT-fibroatheroma than non-OCT-fibroatheroma. The remodeling index of OCT-fibroatheroma assessed by MDCT and IVUS were higher than those of non-OCT-fibroatheroma. The sensitivity, specificity, positive predict values, negative predict values and accuracy of ring-like sign by MDCT and VH-IVUS for detecting OCT-fibroatheroma were 43, 95, 90, 64, 70 % and 71, 45, 56, 63, 58 %, respectively. Our results suggest that both accuracies of MDCT and VH-IVUS to detect OCT-fibroatheroma are insufficient. We need to apply appropriate device for searching vulnerable plaque.
    10/2013; DOI:10.1007/s12928-013-0219-3
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    ABSTRACT: This study sought to investigate the relationship between the degree of microvascular dysfunction assessed by a dual-sensor guidewire (pressure and Doppler velocity) and left ventricular (LV) remodeling after successful primary percutaneous coronary intervention (PPCI) for a first anterior acute myocardial infarction (AMI). Microvascular dysfunction after AMI is associated with progressive LV dilation. In 24 consecutive patients, the microvascular resistance index (MVRI) immediately after PPCI was calculated as the ratio of the mean distal pressure to average peak flow velocity during maximal hyperemia. Cardiac magnetic resonance was performed to determine LV volumes at baseline and 8-month follow-up. LV remodeling was defined as an increase in left ventricular end-diastolic volume (LVEDV) of ≥20%. In patients with an MVRI greater than the median value of 2.96 mm Hg·cm(-1)·s, the LVEDV increased significantly from 117.1 ± 20.7 ml at baseline to 146.5 ± 21.4 ml (p = 0.006) at 8 months, whereas it did not change between baseline and 8 months (108.2 ± 21.2 ml vs. 111.6 ± 29.9 ml, p = 0.620) in patients with an MVRI ≤2.96 mm Hg·cm(-1)·s. LV remodeling was more frequent in the group with an MVRI >2.96 mm Hg·cm(-1)·s (64% vs. 15%, p = 0.033). Furthermore, there was a positive correlation between MVRI and the percentage of increase or decrease in LVEDV (r = 0.42, p = 0.042). Logistic regression analysis showed that MVRI was the strongest univariate predictor of LV remodeling. The best cutoff value of MVRI was 2.96 mm Hg·cm(-1)·s with a sensitivity of 78% and a specificity of 73%. MVRI immediately after PPCI predicts LV remodeling in patients with reperfused anterior AMI.
    JACC. Cardiovascular Interventions 10/2013; 6(10):1046-54. DOI:10.1016/j.jcin.2013.05.014 · 7.44 Impact Factor
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    ABSTRACT: Polymer damage of drug-eluting stents (DES) during percutaneous coronary intervention procedure could be associated with stent restenosis. We assessed the damage to the drug-containing polymer of DES during multiple stenting in a phantom model by using scanning-electron microscopy (SEM). Unexpanded sirolimus-eluting stent (SES; n = 15) was delivered through the formerly expanded SES (n = 15) in a bended polytetrafluoroethylene plastic tube. The stent was subcategorized into 4 segments (S), including distal (S1), mid distal (S2), mid proximal (S3) and proximal segments (S4), for qualitative SEM assessment. Polymer damage, such as detachments, missing or tears, was observed not only in the outer surface of the unexpanded stents (100 %) but also in the inner surface of the formerly expanded stents (100 %). There was a significant difference in the frequency of polymer damage among the 4 segments in the unexpanded stents (S1 vs. S2 vs. S3 vs. S4: 86.7 vs. 80.0 vs. 53.3 vs. 40.0 %, p = 0.022) and the formerly expanded stents (S1 vs. S2 vs. S3 vs. S4: 80.0 vs. 73.3 vs. 73.3 vs. 40.0 %, p = 0.041). The damage was distributed more frequently in distal part than proximal part of either unexpanded stents (S1 vs. S4, p = 0.0079) and the formerly expanded stents (S1 vs. S4, p = 0.0079). Delivery of DES through a formerly expanded DES could cause damage to drug-containing polymer of the stents.
    The international journal of cardiovascular imaging 09/2013; 29(8). DOI:10.1007/s10554-013-0289-4 · 2.32 Impact Factor
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    ABSTRACT: Spontaneous coronary artery dissection (SCAD) found typically in young females without classical coronary risk factors is thought to be a very rare cause of acute coronary syndrome (ACS). The prevalence of SCAD in ACS subjects has been unclear, probably due to the nature of coronary angiography. The aim of this study was to use optical coherence tomography (OCT) to investigate the prevalence of SCAD in ACS. This study consisted of 326 patients with ACS (with or without ST-segment elevation) who underwent OCT to explore the entire culprit artery. According to OCT findings, patients were divided into a SCAD, a plaque rupture (PR), and a non-SCAD/non-PR group. OCT revealed 13 (4.0%) SCADs and 160 (49.1%) plaque ruptures in ACS subjects. The percentage of females versus males was greater in the SCAD group (SCAD: 53.8% vs. PR: 20.0% vs. non-SCAD/non-PR: 23.5%, p=0.02) while no difference was observed in age (SCAD: 67.3±13.3 vs. PR: 66.5±11.1 vs. non-SCAD/non-PR: 67.0±10.5, p=0.90). The prevalence of dyslipidemia (SCAD: 30.8% vs. PR: 63.8% vs. non-SCAD/non-PR: 67.5%, p=0.03) and current smoking (SCAD: 7.7% vs. PR: 57.9% vs. non-SCAD/non-PR: 59.7%, p<0.01) were significantly lower in the SCAD group. SCAD is not a rare cause for ACS, especially in females without classical coronary risk factors.
    09/2013; 61(10). DOI:10.1177/2048872613504310
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    ABSTRACT: Background: Although low high-density lipoprotein cholesterol (HDL-C) level has been reported as an independent risk factor for coronary artery disease, few studies addressed the direct relationship between the presence of thin-cap fibroatheroma (TCFA) that is considered as vulnerable plaque in pathology and HDL-C level. The aim of this study was to investigate whether lesion vulnerability is related to HDL-C level in patients with acute coronary syndrome (ACS). Methods and Results: A total of 261 patients with ACS who underwent optical coherence tomography prior to percutaneous coronary intervention, were enrolled. Patients were divided into a TCFA group (n=124) and a non-TCFA group (n=137). TCFA was defined as a lipid plaque (lipid content in ≥1 quadrant) covered with <70m-thickness fibrous caps. There were no differences in patient characteristics and clinical results between the 2 groups except for HDL-C level, low-density lipoprotein cholesterol (LDL-C) level, and high-sensitive C-reactive protein (hs-CRP) level. On multivariate regression analysis, low HDL-C level (β coefficient: 0.302, P<0.001), high LDL-C level (β coefficient: -0.172, P=0.008), hs-CRP level (β coefficient: -0.145, P=0.017), and current smoking (β coefficient: -0.124, P=0.028) were identified as independent contributors to fibrous cap thickness. Conclusions: HDL-C is correlated with fibrous cap thickness of the culprit lesion in patients with ACS. HDL-C may be considered as a therapeutic target for plaque stabilization.
    Circulation Journal 09/2013; 77(12). DOI:10.1253/circj.CJ-13-0512 · 3.69 Impact Factor
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    ABSTRACT: The aim of the study was to investigate whether intravascular ultrasound (IVUS) can predict microvascular obstruction (MVO) as detected by magnetic resonance imaging (MRI) after primary percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction (STEMI). MVO occurs in a sizable proportion of patients with acute myocardial infarction despite successful PCI and results in poor clinical outcomes. We assessed infarct-related lesions in 68 patients with STEMI by using IVUS before primary PCI. All patients were examined by MRI 1 week after primary PCI. MRI-derived MVO was seen in 23 patients (34%). In the IVUS assessment, the frequency of plaque rupture, echolucent plaque, calcification and positive remodeling, and quantitative geometric data were not different between the MVO group and the no-MVO group. Although the frequency of plaque with ultrasound attenuation was similar between the 2 groups (87% vs. 89%, p = 0.999), the maximum attenuation angle (280° [range, 215° to 360°] vs. 150° [95° to 300°], p = 0.008) and attenuation length (11.3 mm [7.2 mm to 17.8 mm] vs. 6.8 mm [3.0 mm to 10.4 mm], p = 0.009) were significantly greater in the MVO group than the no-MVO group. Multivariable logistic regression analysis showed that attenuated plaque with a maximum attenuation angle of >180° and attenuation length of >5 mm was an independent predictor of MVO (odds ratio: 6.07, 95% confidence interval: 1.89 to 19.53, p = 0.002). Attenuated plaque with maximum attenuation angle of >180° and attenuation length of >5 mm was associated with the occurrence of MVO after primary PCI. IVUS might to be a useful tool for risk stratification in STEMI patients undergoing primary PCI.
    JACC. Cardiovascular Interventions 07/2013; 6(8). DOI:10.1016/j.jcin.2013.01.142 · 7.44 Impact Factor
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    Journal of the American College of Cardiology 03/2013; 61(10). DOI:10.1016/S0735-1097(13)60945-6 · 15.34 Impact Factor
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    ABSTRACT: BACKGROUND: Plaque rupture and secondary thrombus formation play key roles in the onset of acute coronary syndrome (ACS). Plaques showing the napkin-ring sign in multidetector computed tomography (MDCT) have been reported as thin-cap fibroatheroma that is recognized as a precursor lesion for plaque rupture. The purpose of this study was to investigate distribution and frequency of napkin-ring sign and its relationship to features indicating coronary plaque vulnerability on MDCT in patients with coronary artery disease. METHODS: We enrolled 273 patients with ACS (n=61) or stable angina pectoris (SAP, n=212) who were assessed by MDCT. The definition of the napkin-ring sign was the presence of a ring of high attenuation and the CT attenuation of a ring presenting higher than those of the adjacent plaque and no greater than 130HU. RESULTS: The culprit plaques with the napkin-ring sign show higher remodeling index and lower CT attenuation (1.15±0.12 vs. 1.02±0.12, p<0.01 and 39.9±22.8 vs. 72.7±26.6, p<0.01, respectively). Napkin-ring sign at culprit lesions was more frequent in patients with ACS than those with SAP (49.0% vs. 11.2%, p<0.01). Moreover, napkin-ring sign at non-culprit lesions was more frequently observed in ACS patients compared with SAP patients (12.7% vs. 2.8%, p<0.01). The distribution of the napkin-ring sign in the right coronary arteries and left circumflex arteries of our population was relatively even, whereas the napkin-ring sign in the left anterior descending artery was common in the proximal sites (p<0.01). CONCLUSIONS: The napkin-ring sign assessed by MDCT represents similar clinical features of fibroatheroma. MDCT could contribute to the search for fibroatheroma.
    Journal of Cardiology 02/2013; 61(6). DOI:10.1016/j.jjcc.2013.01.004 · 2.57 Impact Factor
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    ABSTRACT: Frequency-domain optical coherence tomography (FD-OCT) is a novel technology which provides high-resolution cross-sectional images of coronary arteries. The aim of this study was to evaluate the inter-scan reproducibility of geometric FD-OCT measurements in the clinical setting. We examined 20 coronary lesions using FD-OCT. Following the FD-OCT image acquisition (1(st) pullback), and after the disengagement and re-engagement of the guiding catheter, an additional acquisition (2(nd) pullback) was performed using a new FD-OCT catheter. There was excellent correlation for minimum lumen area (r = 0.99, P < 0.001), lesion length (r = 0.99, P < 0.001) and lumen volume (r = 0.99, P < 0.001) between the 1(st) pullback and the 2(nd) pullback. The Bland-Altman test demonstrated good agreement between the 1(st) pullback and the 2(nd) pullback: the mean difference for minimum lumen area, lesion length, and lumen volume was 0.05 mm(2), 0.03 mm, and 0.70 mm(3), respectively; and the lower and upper limit of agreement for minimum lumen area, lesion length, and lumen volume was -0.58 and 0.48, -0.36 and 0.42, and -13.4 and 12.1, respectively. FD-OCT showed an excellent inter-scan reproducibility for the geometric coronary artery measurements. Our findings emphasize the value of FD-OCT as a tool for clinical longitudinal studies of coronary artery disease.
    International Heart Journal 01/2013; 54(2):64-7. DOI:10.1536/ihj.54.64 · 1.13 Impact Factor