1. Articles from Takashi Akasaka

    25-48 of 120 « 1 2 3 4 5 »
    1. Suboptimal agreement between optical coherence tomography and near-infrared spectroscopy for identification of lipid-laden plaque

      Suboptimal agreement between optical coherence tomography and near-infrared spectroscopy for identification of lipid-laden plaque

      Recently developed intracoronary imaging techniques allow real-time, in vivo identification of lipid in atherosclerotic plaques. Optical coherence tomography (OCT), a light-based imaging technique with high axial resolution (10-20 μm), identifies lipid-laden plaques as signal-poor regions with diffuse borders. A validation study performed versus histopathology confirmed the high sensitivity (90% to 94%) and specificity (90% to 92%) of OCT to identify lipid-laden plaques 1 . Near-infrared spectroscopy (NIRS) detects lipid-laden plaque by analysing light absorption that varies depending on the coronary tissue components and the wavelength of the incident near-infrared light. NIRS displays the probability of the presence of lipid-laden plaque on ...

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    2. Morphological and pharmacological determinants of peri-procedural myocardial infarction following elective stent implantation: Optical coherence tomography sub-analysis of the PRASFIT-Elective study

      Morphological and pharmacological determinants of peri-procedural myocardial infarction following elective stent implantation: Optical coherence tomography sub-analysis of the PRASFIT-Elective study

      Background Previous studies have suggested that peri-procedural myocardial infarction (PMI) following percutaneous coronary intervention (PCI) is associated with adverse short- and long-term outcomes, and several morphological predictors of PMI have been studied. However, the determinants of PMI under novel anti-platelet therapy are not fully elucidated. Methods and results PRASFIT-Elective is a multicenter, parallel-group study of PCI patients in non-acute settings receiving either prasugrel or clopidogrel in addition to aspirin. Among 742 study patients, 94 (116 lesions) underwent optical coherence tomography (OCT) to evaluate the area of intra-stent tissue (IST, which comprises tissue protrusion and thrombus) after stenting in addition to ...

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    3. Two-year vascular responses to drug-eluting stents with biodegradable polymer versus durable polymer: An optical coherence tomography sub-study of the NEXT

      Two-year vascular responses to drug-eluting stents with biodegradable polymer versus durable polymer: An optical coherence tomography sub-study of the NEXT

      Background This study aimed to compare very late vascular response after stent implantation between everolimus-eluting stent (EES) with a thin, non-adhesive, durable, biocompatible fluorinated polymer and biolimus-eluting stent (BES) with a biodegradable polymer by optical coherence tomography (OCT). Methods and results In the NOBORI-BES Versus XIENCE V/PROMUS-EES Trial (NEXT), a formal OCT substudy investigated 48 patients (27 EES-treated lesions in 23 patients and 28 BES-treated lesions in 25 patients) with 2-year (18–30 months) follow-up imaging at 18 centers. The percentage of uncovered strut by neointima was significantly lower in EES compared with BES (2.1 ± 4.7% vs ...

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    4. Thrombus and Plaque Erosion Characterized by Optical Coherence Tomography in Patients With Vasospastic Angin

      Thrombus and Plaque Erosion Characterized by Optical Coherence Tomography in Patients With Vasospastic Angin

      Introduction and objectives Vasospastic angina (VSA) can result in endothelial damage and thrombus formation. The aim of this study was to evaluate the incidence of thrombus and plaque characteristics at coronary spasm segments compared with nonspasm segments by using optical coherence tomography (OCT) in patients with suspected VSA. Methods One hundred and eighty-three patients with suspected VSA were enrolled in this study. The ergonovine provocation test was performed in all patients for the diagnosis of VSA except in patients with spontaneous spasm. All target lesions were analyzed by OCT. Plaque erosion was defined as the presence of attached thrombus overlying ...

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    5. Optical coherence tomography compared with intravascular ultrasound and with angiography to guide coronary stent implantation (ILUMIEN III: OPTIMIZE PCI): a randomised controlled trial

      Optical coherence tomography compared with intravascular ultrasound and with angiography to guide coronary stent implantation (ILUMIEN III: OPTIMIZE PCI): a randomised controlled trial

      Background Percutaneous coronary intervention (PCI) is most commonly guided by angiography alone. Intravascular ultrasound (IVUS) guidance has been shown to reduce major adverse cardiovascular events (MACE) after PCI, principally by resulting in a larger postprocedure lumen than with angiographic guidance. Optical coherence tomography (OCT) provides higher resolution imaging than does IVUS, although findings from some studies suggest that it might lead to smaller luminal diameters after stent implantation. We sought to establish whether or not a novel OCT-based stent sizing strategy would result in a minimum stent area similar to or better than that achieved with IVUS guidance and better ...

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    6. Optical Coherence Tomography Predictors for Edge Restenosis After Everolimus-Eluting Stent Implantation

      Optical Coherence Tomography Predictors for Edge Restenosis After Everolimus-Eluting Stent Implantation

      Background— Stent edge restenosis (SER) remains a potential limitation of drug-eluting stents. The aim of this study was to determine optical coherence tomography (OCT) predictors for angiographic late SER after everolimus-eluting stent implantation. Methods and Results— We retrospectively analyzed 319 patients who underwent OCT immediately after everolimus-eluting stent implantation and scheduled 9- to 12-month follow-up angiography. The binary angiographic SER rate was 10% (32/319) in the patients, 8.4% (32/382) in lesions, and 4.4% (33/744) in stent edge segments. In the stent edge segments at post stenting, OCT-derived lipidic plaque (61% versus 20%; P <0.001 ...

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    7. Angiographic, optical coherence tomography and histology findings from combination of a drug-coated balloon with an everolimus-eluting stent in a porcine mode

      Angiographic, optical coherence tomography and histology findings from combination of a drug-coated balloon with an everolimus-eluting stent in a porcine mode

      Background We designed a porcine model to compare the angiographic, optical coherence tomography (OCT) and histological findings of implanting an everolimus-eluting stent (EES) in the same segment of the coronary artery pre-treated with a drug-coating balloon (DCB; paccocath as carrier) with EES alone and DCB plus a bare metal stent (BMS). Methods Seven female swine averaging 46.0±2.4 kg were treated by random assignment as follows: DCB followed by EES; DCB followed by BMS; and EES alone. Quantitative coronary angiography (QCA) and OCT were carried out post-implantation and repeated after 28±1 days. Results All arteries remained patent ...

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    8. Assessment of Vascular Response after Stent Implantation by Intracoronary Optical Coherence Tomograph

      Assessment of Vascular Response after Stent Implantation by Intracoronary Optical Coherence Tomograph

      Optical coherence tomography (OCT) is a high resolution (10-20 μm) imaging modality that provides microscopic visualization of the coronary artery including vascular response after stent implantation. Compared to conventional intravascular ultrasound, OCT can more clearly identify findings immediately after stent implantation, such as tissue protrusion, stent edge dissection, and incomplete stent strut apposition. Furthermore, OCT allows clinicians to accurately assess the late acquired stent malapposition and strut coverage which could be a surrogate marker for stent thrombosis after drug-eluting stent (DES) implantation. OCT can evaluate not only the extent and amount of neointima but also the tissue characteristics of neointimal ...

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    9. Reduction of in-stent thrombus immediately after percutaneous coronary intervention by pretreatment with prasugrel compared with clopidogrel: An optical coherence tomography study

      Reduction of in-stent thrombus immediately after percutaneous coronary intervention by pretreatment with prasugrel compared with clopidogrel: An optical coherence tomography study

      Background Prasugrel is a new-generation thienopyridine antiplatelet agent that provides more consistent and prompt platelet inhibition than clopidogrel. The aim of this study was to compare in-stent thrombus inhibition effect of pretreatment with prasugrel and clopidogrel by using optical coherence tomography (OCT) immediately after percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS). Methods We performed OCT immediately after PCI in 108 ACS patients pretreated with either prasugrel ( n = 51) or clopidogrel ( n = 57). OCT detected thrombus/plaque protrusion in all stented segments. Results Although stent volume (190.4 ± 119.1 mm 3 vs. 189.4 ± 95.8 mm 3 ...

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    10. The use of optical coherence tomography in acute coronary syndrome

      The use of optical coherence tomography in acute coronary syndrome

      Optical coherence tomography (OCT) is an intracoronary imaging modality which utilizes near-infrared light to provide high-resolution cross-sectional in-vivo images of the coronary artery. OCT imaging technique enables detailed evaluation of plaque morphology in patients with acute coronary syndrome and helps to understand the underlying mechanisms including plaque rupture, plaque erosion, and calcified nodule. It is useful to optimize percutaneous coronary intervention, and evaluate vascular response to coronary intervention and pharmacological therapy. Advances in intracoronary OCT and further research on clinical applications have the potential to contribute to a better prognosis in acute coronary syndrome.

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    11. Optical frequency domain imaging vs. intravascular ultrasound in percutaneous coronary intervention (OPINION trial): Study protocol for a randomized controlled trial

      Optical frequency domain imaging vs. intravascular ultrasound in percutaneous coronary intervention (OPINION trial): Study protocol for a randomized controlled trial

      Background Optical coherence tomography is becoming increasingly widespread as an adjunctive intravascular diagnostic technique in percutaneous coronary intervention (PCI), because of its ability to visualize coronary structures at high resolution. Several studies have reported that intravascular ultrasound (IVUS) guidance in PCI might be helpful to reduce subsequent stent thrombosis, restenosis, repeat revascularization, myocardial infarction, and cardiac death. The OPtical frequency domain imaging vs. INtravascular ultrasound in percutaneous coronary InterventiON (OPINION) trial is aimed at evaluating the impact of optical frequency domain imaging (OFDI) guidance in PCI on clinical outcomes compared with IVUS guidance. Methods and design The OPINION trial is ...

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    12. Optical coherence tomography assessment of efficacy of thrombus aspiration in patients undergoing a primary percutaneous coronary intervention for acute ST-elevation myocardial infarction

      Optical coherence tomography assessment of efficacy of thrombus aspiration in patients undergoing a primary percutaneous coronary intervention for acute ST-elevation myocardial infarction

      Objective: We used optical coherence tomography (OCT) to assess the impact of thrombus aspiration before angioplasty on poststenting tissue protrusions in patients undergoing a primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI). Methods and results: A total of 188 patients with STEMI who underwent thrombus-aspiration PCI ( n =113) or standard PCI ( n =75) were examined in this study. OCT was performed immediately after primary PCI to assess lesion morphology in the stented segment. The minimum stent area was similar between the thrombus-aspiration PCI group and the standard PCI group [7.4 interquartile range (IQR): 5.8–9 ...

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    13. Comparative analysis method of permanent metallic stents (XIENCE) and bioresorbable poly-L-lactic (PLLA) scaffolds (Absorb) on optical coherence tomography at baseline and follow-up

      Comparative analysis method of permanent metallic stents (XIENCE) and bioresorbable poly-L-lactic (PLLA) scaffolds (Absorb) on optical coherence tomography at baseline and follow-up

      Aims: Fully bioresorbable Absorb poly-L-lactic-acid (PLLA) scaffolds (Abbott Vascular, Santa Clara, CA, USA) are a novel approach for the treatment of coronary narrowing. Due to the translucency of the material (PLLA), the optical coherence tomography (OCT) measurement methods used in the ABSORB trials were unique but not applicable for permanent metallic stents. When the Absorb scaffold and metallic stents are compared in the context of randomised trials, it is challenging to compare the two devices using the conventional methods. The primary purpose of this report is to explain the biases in conventional methodologies applied for metallic stents and for PLLA ...

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    14. Optical coherence tomography assessment of efficacy of thrombus aspiration in patients undergoing a primary percutaneous coronary intervention for acute ST-elevation myocardial infarction

      Optical coherence tomography assessment of efficacy of thrombus aspiration in patients undergoing a primary percutaneous coronary intervention for acute ST-elevation myocardial infarction

      Objective: We used optical coherence tomography (OCT) to assess the impact of thrombus aspiration before angioplasty on poststenting tissue protrusions in patients undergoing a primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI). Methods and results: A total of 188 patients with STEMI who underwent thrombus-aspiration PCI ( n =113) or standard PCI ( n =75) were examined in this study. OCT was performed immediately after primary PCI to assess lesion morphology in the stented segment. The minimum stent area was similar between the thrombus-aspiration PCI group and the standard PCI group [7.4 interquartile range (IQR): 5.8–9 ...

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    15. Comparison of neointimal coverage between everolimus-eluting stents and sirolimus-eluting stents: an optical coherence tomography substudy of the RESET (Randomized Evaluation of Sirolimus-eluting versus Everolimus-eluting stent Trial)

      Comparison of neointimal coverage between everolimus-eluting stents and sirolimus-eluting stents: an optical coherence tomography substudy of the RESET (Randomized Evaluation of Sirolimus-eluting versus Everolimus-eluting stent Trial)

      Aims: The aim of the present study was to compare vascular healing response between the first-generation sirolimus-eluting stent (SES) and the second-generation everolimus-eluting stent (EES) by using optical coherence tomography (OCT). Methods and results: The RESET was a prospective, multicentre, randomised, open-label trial comparing EES and SES. Of the 3,197 patients enrolled in the RESET, nine-month follow-up OCT after stent implantation was performed in 100 patients (48 EES-treated lesions in 44 patients and 62 SES-treated lesions in 56 patients), thus constituting the OCT substudy population. The percentage of uncovered struts per lesion (8±15% vs. 14±19%, p=0 ...

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    16. OCT–Defined Morphological Characteristics of Coronary Artery Spasm Sites in Vasospastic Angina

      OCT–Defined Morphological Characteristics of Coronary Artery Spasm Sites in Vasospastic Angina

      Objectives The aim of this study was to define the morphological features of coronary artery spasm sites using optical coherence tomography (OCT) in patients with vasospastic angina (VSA). Background Plaque characteristics at coronary artery spasm sites have not been investigated systematically. Methods Sixty-nine consecutive patients (80 spasm sites) presenting with VSA who underwent OCT imaging were included in this study. Fibrous cap disruption was identified by the discontinuation of fibrous cap with or without intraplaque cavity formation. OCT-defined erosion was established by the presence of thrombus with or without lumen irregularity overlying an intact fibrous cap on multiple adjacent OCT ...

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    17. Optimal threshold of postintervention minimum stent area to predict in-stent restenosis in small coronary arteries: An optical coherence tomography analysis

      Optimal threshold of postintervention minimum stent area to predict in-stent restenosis in small coronary arteries: An optical coherence tomography analysis

      Objectives The aim of this study was to determine the best threshold of postintervention minimum stent area (MSA) assessed by optical coherence tomography (OCT) to predict long-term in-stent restenosis (ISR) for 2.5 mm-diameter everolimus-eluting stents (EES). Background Percutaneous coronary intervention (PCI) for small coronary arteries remains challenging. Stent underexpansion is a strong predictor of late ISR. Methods We performed a retrospective analysis of 69 lesions in 69 patients undergoing PCI with 2.5 mm-diameter stents using OCT for the assessment of postintervention MSA and subsequent 9-month angiographic follow-up. Results The rates of angiographic ISR and target lesion revascularization were ...

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    18. Optical coherence tomography imaging during percutaneous coronary intervention impacts physician decision-making: ILUMIEN I Study

      Optical coherence tomography imaging during percutaneous coronary intervention impacts physician decision-making: ILUMIEN I Study

      Aims ILUMIEN I is the largest prospective, non-randomized, observational study of percutaneous coronary intervention (PCI) procedural practice in patients undergoing intra-procedural pre- and post-PCI fractional flow reserve (FFR) and optical coherence tomography (OCT). We report on the impact of OCT on physician decision-making and the association with post-PCI FFR values and early clinical events. Methods and results Optical coherence tomography and documentary FFR were performed pre- and post-PCI in 418 patients (with 467 stenoses) with stable or unstable angina or NSTEMI. Based on pre-PCI OCT, the procedure was altered in 55% of patients (57% of all stenoses) by selecting different ...

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    19. Optical coherence tomography assessment of efficacy of thrombus aspiration in patients undergoing a primary percutaneous coronary intervention for acute ST-elevation myocardial infarction

      Optical coherence tomography assessment of efficacy of thrombus aspiration in patients undergoing a primary percutaneous coronary intervention for acute ST-elevation myocardial infarction

      Objective: We used optical coherence tomography (OCT) to assess the impact of thrombus aspiration before angioplasty on poststenting tissue protrusions in patients undergoing a primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI). Methods and results: A total of 188 patients with STEMI who underwent thrombus-aspiration PCI (n=113) or standard PCI (n=75) were examined in this study. OCT was performed immediately after primary PCI to assess lesion morphology in the stented segment. The minimum stent area was similar between the thrombus-aspiration PCI group and the standard PCI group [7.4 interquartile range (IQR): 5.8-9.4 ...

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    20. Vasa Vasorum Restructuring in Human Atherosclerotic Plaque Vulnerability

      Vasa Vasorum Restructuring in Human Atherosclerotic Plaque Vulnerability

      Background Previous studies have suggested that vasa vasorum (VV) is associated with plaque progression and vulnerability. Objectives The aim of this study was to investigate the relationship between coronary neovascularization structures and plaque characteristics. Methods 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 ...

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    21. Optical coherence tomography and intravascular ultrasound evaluation of cardiac allograft vasculopathy with and without intimal neovascularization

      Optical coherence tomography and intravascular ultrasound evaluation of cardiac allograft vasculopathy with and without intimal neovascularization

      Aims Neovascularization is closely associated with plaque progression in non-heart transplantation subjects; on the other hand, cardiac allograft vasculopathy causes unfavourable outcomes. Intravascular ultrasound (IVUS) and optical coherence tomography (OCT) can provide microscopic assessment in vivo . The aim of this study was to investigate the impact of neovascularization on intimal proliferation. Methods and results Both IVUS and OCT were attempted in 45 consecutive patients during annual catheterization after heart transplantation. There were 115 vessels [28 vessels were catheterized within 8 weeks of heart transplantation (baseline)]. IVUS analysis assessed vessel, luminal, and intimal (vessel-lumen) volume using Simpson's method. Qualitative parameters ...

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    22. Successful Stenting With Optical Frequency Domain Imaging Guidance For Spontaneous Coronary Artery Dissection

      Successful Stenting With Optical Frequency Domain Imaging Guidance For Spontaneous Coronary Artery Dissection

      A 51-year-old woman was urgently admitted because of chest pain. Emergent coronary angiography revealed diffuse stenosis from the proximal to distal portion of the right coronary artery (RCA) with Thrombolysis In Myocardial Infarction (TIMI) flow grade 2 (Figure 1 ). No stenosis was seen in the left coronary artery. Intravascular ultrasound (IVUS) images revealed an intracoronary hematoma from the posterior descending artery (PDA) to the ostium of the RCA, but could not demonstrate the entry point of the hematoma (Figure 1 ). Optical frequency domain imaging (OFDI; Terumo, Tokyo, Japan) images clearly demonstrated, not only intracoronary hematoma from the PDA to the ...

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    23. Assessment of vascular response after drug-eluting stents implantation in patients with diabetes mellitus: an optical coherence tomography sub-study of the J-DESsERT

      Assessment of vascular response after drug-eluting stents implantation in patients with diabetes mellitus: an optical coherence tomography sub-study of the J-DESsERT

      Even in the drug-eluting stent era, diabetes mellitus (DM) patients have high incidences of restenosis and repeat revascularization after percutaneous coronary intervention. The aim of this study was to compare vascular response after stent implantation between sirolimus-eluting stent (SES) and paclitaxel-eluting stent (PES) by using optical coherence tomography (OCT) in DM patients as well as in non-DM patients. In the Japan-Drug Eluting Stents Evaluation; a Randomized Trial (J-DESsERT), the OCT sub-study enrolled 75 patients who underwent 8 months follow-up imaging after SES or PES implantation. Mean neointimal hyperplasia (NIH) thickness was significantly thinner in SES than PES in the DM ...

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    24. Feasibility of Optical Coronary Tomography in Quantitative Measurement of Coronary Arteries With Lipid-Rich Plaque

      Feasibility of Optical Coronary Tomography in Quantitative Measurement of Coronary Arteries With Lipid-Rich Plaque

      Background: The aim of the present study was to evaluate the feasibility of optical coherence tomography (OCT) for measurement of vessel area in coronary arteries with lipid-rich plaque as compared with intravascular ultrasound (IVUS). Methods and Results: We investigated 80 coronary artery segments with lipid-rich plaque on OCT and non-attenuated plaque on IVUS. According to the lipid arc on OCT, the plaques were classified into 4 groups: group 1, lipid arc ≤90°; group 2, 90°<lipid arc≤180°; group 3, 180°<lipid arc≤270°; group 4, lipid arc >270°. Vessel circular arcs that could not be identified due to OCT ...

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    1. (118 articles) Takashi Akasaka
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