Yuichi Ozaki

Wakayama Medical University, Wakayama, Wakayama, Japan

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Publications (33)92.01 Total impact

  • [show abstract] [hide abstract]
    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; · 1.23 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 01/2014; 233(2):697–703. · 3.71 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 11/2013; · 2.51 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; · 3.58 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.
    Cardiovascular intervention and therapeutics. 10/2013;
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    ABSTRACT: It remains unclear whether glycemic fluctuation can affect plaque rupture in acute myocardial infarction (AMI). Here we investigate the impact of glucose fluctuation on plaque rupture, as observed by optical coherence tomography (OCT), and monocyte subsets in patients with AMI. We studied 37 consecutive patients with AMI. All patients underwent OCT examination, which revealed 24 patients with plaque rupture and 13 patients without plaque rupture at the culprit site. Peripheral blood sampling was performed on admission. Three monocyte subsets (CD14(+)CD16(-), CD14(bright)CD16(+), and CD14(dim)CD16(+)) were assessed by flow cytometry. Glycemic variability, expressed as the mean amplitude of glycemic excursion (MAGE), was determined by a continuous glucose monitoring system 7 days after the onset of AMI. MAGE was significantly higher in the rupture patients than in the non-rupture patients (P=0.036). Levels of CD14(bright)CD16(+) monocytes from the rupture patients were significantly higher than those from the non-rupture patients (P=0.042). Of interest, levels of CD14(bright)CD16(+) monocytes correlated positively and significantly with MAGE (r=0.39, P=0.02). Dynamic glucose fluctuation may be associated with coronary plaque rupture, possibly through the preferential increase in CD14(bright)CD16(+) monocyte levels.
    Nutrition, metabolism, and cardiovascular diseases: NMCD 10/2013; · 3.52 Impact Factor
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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.
    10/2013; 6(10):1046-54. · 1.07 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; · 2.15 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.
    European heart journal. Acute cardiovascular care. 09/2013;
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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; · 3.58 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.
    07/2013; · 1.07 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; · 2.30 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. · 1.23 Impact Factor
  • European heart journal cardiovascular Imaging. 08/2012;
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    ABSTRACT: Background: Elevated blood glucose on admission may worsen outcome after acute myocardial infarction (AMI). No relationship has been identified between admission blood glucose level and myocardial salvage in patients with AMI. Methods and Results: This study assessed 150 consecutive patients with a first AMI who underwent percutaneous coronary intervention within 24h from onset of symptoms. Plasma blood glucose was measured on admission. Stress hyperglycemia was defined as blood glucose ≥10mmol/L (180mg/dl). The extent of myocardial salvage 7 days after AMI was evaluated on cardiovascular magnetic resonance imaging (CMRI) as the difference between areas of myocardium at risk (T2-weighted hyperintense lesion) and areas of late gadolinium enhancement. The association between stress hyperglycemia and myocardial salvage index (MSI) was investigated in patients with and without diabetes. Among non-diabetic patients, MSI was lower in those with stress hyperglycemia than in those without. No significant difference in MSI was noted between diabetes patients with or without stress hyperglycemia. On multivariate analysis, stress hyperglycemia in patients without diabetes was an independent predictor of MSI. Conclusions: Stress hyperglycemia affects MSI, indicating that the manipulation of glucose levels could be a potential therapeutic target for salvaging ischemic damage.  (Circ J 2012; 76: 2690-2696).
    Circulation Journal 08/2012; 76(11):2690-6. · 3.58 Impact Factor
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    ABSTRACT: Background: Circulating monocytes can be divided into 2 subsets typically identified by the expression of CD14 and CD16. Although previous studies have shown that circulating monocytes contribute to the progression of coronary atherosclerotic lesions, the relationship between the severity of coronary artery disease (CAD) and the 2 distinct monocyte subsets has not previously been evaluated. We investigated the relationship between the monocyte subsets and the severity of CAD assessed by coronary angiography (CAG) in patients with stable angina pectoris (SAP). Methods and Results: We enrolled 125 patients who underwent diagnostic CAG. Patients were divided into 3 groups: those without CAD, those with single-vessel disease (SVD), and those with multiple-vessel disease (MVD). In addition, the severity of CAD was evaluated by Gensini score. The 2 monocyte subsets (CD14(+)CD16(-) and CD14(+)CD16(+)) were measured by flow cytometry. Circulating CD14(+)CD16(+) monocytes were more frequently observed in patients with MVD than in those with SVD or without CAD. The proportion of CD14(+)CD16(+) monocytes positively correlated with Gensini score (r=0.618, P<0.001). Multivariate logistic regression analysis revealed that the proportion of CD14(+)CD16(+) monocytes was an independent contributor to MVD (odds ratio: 1.475; 95% confidence interval: 1.273-1.708, P<0.001). Conclusions: A preferential increase in peripheral CD14(+)CD16(+) monocytes may be closely related to the severity of CAD in patients with SAP.  (Circ J 2012; 76: 2412-2418).
    Circulation Journal 06/2012; 76(10):2412-8. · 3.58 Impact Factor
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    ABSTRACT: Background: For the identification of functionally significant coronary artery disease, there have not been any dedicated optical coherence tomography (OCT) studies reported previously, although OCT can clearly detect coronary vessel lumina at higher resolution than intravascular ultrasound (IVUS). Methods and Results: OCT and fractional flow reserve (FFR) measurements were performed in 62 intermediate coronary lesions in 59 patients. FFR was calculated as the ratio of distal coronary pressure divided by proximal coronary pressure during maximal hyperemia. FFR <0.75 was used as the threshold for diagnosing functionally significant stenosis. Minimal lumen area (MLA), minimal lumen diameter (MLD) and percent lumen area stenosis were measured by OCT. FFR values correlated significantly with OCT-derived MLA (r=0.75, P<0.01), MLD (r=0.76, P<0.01) and percent lumen area stenosis (r=-0.77, P<0.01). Receiver-operating characteristic curve suggested an OCT-derived MLA <1.91mm(2) (sensitivity 93.5%, specificity 77.4%), MLD <1.35mm (sensitivity 90.3%, specificity 80.6%) and percent lumen area stenosis >70.0% (sensitivity 96.8%, specificity 83.9%) as the best cutoff values for a FFR <0.75. Conclusions: Anatomical measurements of coronary stenosis obtained by OCT show significant correlation with FFR. OCT has the potential to predict functionally significant stenosis, although the present OCT-derived parameters were smaller than those reported in previous IVUS studies.  (Circ J 2012; 76: 2218-2225).
    Circulation Journal 06/2012; 76(9):2218-25. · 3.58 Impact Factor
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    ABSTRACT: Coronary artery perforation is a rare but catastrophic complication of percutaneous coronary intervention (PCI). PCI for chronic total occlusion (CTO) lesions is associated with lower procedural success rate and higher incidence of complications as compared with non-CTO coronary vessels. Here we report a rare case of a patient who developed coronary perforation during PCI for the CTO lesion and suffered from delayed cardiac tamponade due to collateral flow from the contralateral coronary artery despite complete hemostasis of the perforated site by the covered stent.
    Cardiovascular intervention and therapeutics. 06/2012; 27(3):205-9.
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    ABSTRACT: Neointima inside the bare-metal stents (BMSs) can transform into atherosclerotic tissue during an extended follow-up because of a persistent inflammatory reaction to the metal. We sought to investigate whether strut thickness may impact on the atherosclerotic change in neointima 4 years or more after BMS implantation using optical coherence tomography. Forty-six stented lesions of 41 patients with BMS ≥ 4 years after implantation who underwent optical coherence tomography were enrolled in the study. The strut was defined as thin when less than 100 μm and thick when ≥ 100 μm. According to these criteria, stents were divided into 2 groups (thin strut n = 19, thick strut n = 27). Neointimal tissue was categorized into normal neointima, characterized by a signal-rich band without signal attenuation, or lipid-laden intima, with marked signal attenuation and a diffuse border. Intimal disruption, thrombus, and neovascularization were also evaluated. The mean period after implantation was 98.2 ± 25.8 months in the thin-strut group and 91.1 ± 22.8 months in the thick-strut group (P = .330). Lipid-laden intima (70% vs 32%, P = .016), thin-cap fibroatheroma-like intima (59% vs 16%, P = .0056), and intimal disruption (48% vs 16%, P = .031) were observed more frequently in the thick-strut group than in the thin-strut group, but no significant difference was observed in the frequency of thrombus. Although peristrut neovascularization was a common finding in both groups (thick vs thin 81% vs 79%, P = 1.000), the frequency of intraintima neovascularization tended to be higher in the thick-strut group (67% vs 42%, P = .135). A thinner strut thickness may have favorable effects on neointimal atherosclerotic changes after BMS implantation.
    American heart journal 04/2012; 163(4):608-16. · 4.65 Impact Factor
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    ABSTRACT: It remains unclear whether angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin II type 1 receptor blockers (ARBs) have fully delivered the expected reduction in cardiovascular diseases. We investigated the effects of adding the direct renin inhibitor (DRI), aliskiren, to an ACEI or an ARB on monocyte subsets and myocardial salvage in patients with primary acute myocardial infarction (AMI). Twenty-one consecutive patients were treated with an ACEI or an ARB (non-DRI group), and another 21 consecutive patients received aliskiren combined with an ACEI or an ARB (DRI group). Two monocyte subsets (CD14(+)CD16(-) and CD14(+)CD16(+)) were measured by flow cytometry. The extent of myocardial salvage 7 days after AMI was evaluated by cardiac magnetic resonance imaging. Both plasma renin activity and aldosterone levels were significantly lower in the DRI group than in the non-DRI group. Peak levels of CD14(+)CD16(-) monocyte number and ratio were also significantly lower in the DRI group. The extent of myocardial salvage was significantly higher in the DRI group than in the non-DRI group (44.8 [41.2-53.1] vs. 36.0 [28.5-42.6], P=0.001). A DRI combined with an ACEI or an ARB can better improve the extent of myocardial salvage after AMI than an ACEI or an ARB alone in association with the decrease in circulating CD14(+)CD16(-) monocytes.
    Circulation Journal 03/2012; 76(6):1461-8. · 3.58 Impact Factor