1. Articles from Tsunekazu Kakuta

    1-24 of 40 1 2 »
    1. Predictors of Rapid Plaque Progression: An Optical Coherence Tomography Study

      Predictors of Rapid Plaque Progression: An Optical Coherence Tomography Study

      Objectives This study sought to identify morphological predictors of rapid plaque progression. Background Two patterns of plaque progression have been described: slow linear progression and rapid step-wise progression. The former pattern will cause stable angina when the narrowing reaches a critical threshold, whereas the latter pattern may lead to acute coronary syndromes or sudden cardiac death. Methods Patients who underwent optical coherence tomography (OCT) imaging during the index procedure and follow-up angiography with a minimum interval of 6 months were selected. Nonculprit lesions with a diameter stenosis of ≥30% on index angiography were assessed. Lesion progression was defined as a ...

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    2. Spatial Distribution of Vulnerable Plaques: Comprehensive In Vivo Coronary Plaque Mapping

      Spatial Distribution of Vulnerable Plaques: Comprehensive In Vivo Coronary Plaque Mapping

      Objectives The authors performed a comprehensive analysis on the distribution of coronary plaques with different phenotypes from our 3-vessel optical coherence tomography (OCT) database. Background Previous pathology studies demonstrated that thin-cap fibroatheroma (TCFA) is localized in specific segments of the epicardial coronary arteries. A detailed description of in vivo coronary plaques of various phenotypes has not been reported. Methods OCT images of all 3 coronary arteries in 131 patients were analyzed every 1 mm to assess plaque phenotype and features of vulnerability. In addition, plaques were divided into tertiles according to percent area stenosis (%AS). Results Among 534 plaques identified ...

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    3. Prognostic impact of healed coronary plaque in non-culprit lesions assessed by optical coherence tomography

      Prognostic impact of healed coronary plaque in non-culprit lesions assessed by optical coherence tomography

      Background and Aims We sought to investigate the characteristics and prognostic impact of healed plaque (HP) detected by optical coherence tomography (OCT) in non-culprit segments in treated vessels. Methods OCT analysis included HP having a different optical intensity with clear demarcation from underlying plaque, thin-cap fibroatheroma (TCFA), and minimal lumen area. Non-culprit lesion (NCL) was defined as a plaque with >90º arc of disease (≥0.5mm intimal thickness), length ≥2 mm, and location >5 mm from the stent edges. Major adverse cardiac event (MACE) included cardiac death, myocardial infarction (MI), or ischemia-driven revascularization (IDR). Results We studied a total of ...

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    4. Circadian variations in pathogenesis of ST-segment elevation myocardial infarction: an optical coherence tomography study

      Circadian variations in pathogenesis of ST-segment elevation myocardial infarction: an optical coherence tomography study

      Previous studies have reported a circadian variation in the onset of ST-segment elevation myocardial infarction (STEMI). However, underlying mechanisms for the circadian variation have not been fully elucidated. We investigated the relationship between onset of STEMI and the underlying pathology using optical coherence tomography (OCT). Patients with a diagnosis of STEMI were selected from a multicenter OCT registry. Patients were divided into 4 groups based on the estimated time of onset (00:00–05:59, 06:00–11:59, 12:00–17:59, or 18:00–23:59). Underlying pathologies of MI (plaque rupture, plaque erosion, and calcified plaque) were ...

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    5. Predictors for layered coronary plaques: an optical coherence tomography study

      Predictors for layered coronary plaques: an optical coherence tomography study

      Healed coronary plaques, morphologically characterized by a layered pattern, are signatures of previous plaque disruption and healing. Recent optical coherence tomography (OCT) studies showed that layered plaque is associated with vascular vulnerability. However, factors associated with layered plaques have not been studied. The aim of this study was to investigate predictors for layered plaque at the culprit plaques and at non-culprit plaques. Patients with coronary artery disease who underwent pre-intervention OCT imaging of the culprit lesion were included. Layered plaques were defined as plaques with one or more layers of different optical density and a clear demarcation from underlying components ...

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    6. COMPARISON OF POST STENT OPTICAL COHERENCE TOMOGRAPHY FINDINGS AMONG THREE SUBTYPES OF CALCIFIED CULPRIT PLAQUES IN PATIENTS WITH ACUTE CORONARY SYNDROME

      COMPARISON OF POST STENT OPTICAL COHERENCE TOMOGRAPHY FINDINGS AMONG THREE SUBTYPES OF CALCIFIED CULPRIT PLAQUES IN PATIENTS WITH ACUTE CORONARY SYNDROME

      Background Recently, three subtypes of calcified plaques at the culprit lesion were reported in patients with acute coronary syndrome (ACS): eruptive calcified nodule, superficial calcific sheet, and calcified protrusion. Methods A total of 157 patients with ACS and calcified plaque at the culprit lesion were selected from our database. Optical coherence tomography (OCT) findings at index procedure and after stent implantation were compared among the three subgroups. Results In the final analysis, 92 cases were included. Pre-procedural OCT showed eruptive calcified nodules in 20 (21.7%) cases, superficial calcific sheets in 66 (71.7%), and calcified protrusion in 6 (6 ...

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    7. Comprehensive In Vivo Coronary Plaque Mapping: A 3-Vessel Optical Coherence Tomography Study

      Comprehensive In Vivo Coronary Plaque Mapping: A 3-Vessel Optical Coherence Tomography Study

      Background Previous pathology studies demonstrated that thin-cap fibroatheroma (TCFA) is localized in specific segments of the epicardial coronary arteries. A detailed description of in vivo coronary plaques of various phenotypes has not been reported. Objectives We performed a comprehensive analysis on the distribution of coronary plaques with different phenotypes from our 3-vessel optical coherence tomography (OCT) database. Methods OCT images of all 3 coronary arteries in 131 patients were analyzed every 1 mm to assess plaque phenotype and features of vulnerability. In addition, plaques were divided into tertiles according to percent area stenosis (%AS). Results Among 534 plaques identified in ...

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    8. Comparison of post‐stent optical coherence tomography findings among three subtypes of calcified culprit plaques in patients with acute coronary syndrome

      Comparison of post‐stent optical coherence tomography findings among three subtypes of calcified culprit plaques in patients with acute coronary syndrome

      Objectives To compare the postprocedural optical coherence tomography (OCT) findings and in‐hospital outcomes among the three subtypes of calcified plaques: eruptive calcified nodules, superficial calcific sheet, and calcified protrusion. Background Recently, three subtypes of calcified culprit plaques were reported in patients with acute coronary syndrome (ACS). How these subtypes respond to stenting is unknown. Methods ACS patients with calcified plaque at the culprit lesion were selected from our database. OCT findings at baseline and after stent implantation were compared. Results In the final analysis, 87 cases were included. Preprocedural OCT showed eruptive calcified nodules in 19 (21.8%) cases ...

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    9. Plaque morphology assessed by optical coherence tomography in the culprit lesions of the first episode of acute myocardial infarction in patients with low low-density lipoprotein cholesterol level

      Plaque morphology assessed by optical coherence tomography in the culprit lesions of the first episode of acute myocardial infarction in patients with low low-density lipoprotein cholesterol level

      Background There remains a residual risk for acute myocardial infarction (AMI) even with low low-density lipoprotein cholesterol (LDL-C) levels. This study aimed to characterize the culprit lesion morphology of AMI by optical coherence tomography (OCT) in patients with low LDL-C. Methods Four-hundred and nine culprit lesions of 409 patients with their first presentation of AMI imaged by OCT were investigated. OCT analysis included the presence of plaque rupture and thin-capped fibroatheroma (TCFA). Fibrous cap thickness and lipid length were also measured. Intravascular ultrasound (IVUS) was performed in 368 (90.0%) patients. OCT and IVUS findings were compared between patients with ...

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    10. Primary percutaneous coronary intervention for a left main bifurcation lesion without stenting using excimer laser with optical coherence tomography guidance: a case report

      Primary percutaneous coronary intervention for a left main bifurcation lesion without stenting using excimer laser with optical coherence tomography guidance: a case report

      Background Optimal strategy for treating bifurcation lesions or lesions with large thrombus in left main disease remains elusive. Excimer laser coronary angioplasty (ELCA) is a therapeutic option for thrombotic lesions in acute coronary syndrome. Case summary A 68-year-old man with chest pain was transferred to our emergency department, and subsequently diagnosed as inferior ST-segment elevation myocardial infarction (STEMI). Emergent coronary angiography revealed a 75% stenosis in the left main trunk (LMT). Optical coherence tomography (OCT) showed massive thrombus at the distal LMT to the ostial left anterior descending artery (LAD) and left circumflex artery (LCx). ELCA was performed in the ...

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      Mentions: Tsunekazu Kakuta
    11. Subclinical Calcified Nodules in Saphenous Vein Graft on High-Resolution Coronary Angioscopy

      Subclinical Calcified Nodules in Saphenous Vein Graft on High-Resolution Coronary Angioscopy

      Long-term patency of saphenous vein graft (SVG) remains challenging.1 A 75-year-old man on hemodialysis had undergone coronary artery bypass grafting (CABG) 11 years earlier. At the current presentation he underwent percutaneous coronary intervention (PCI) for SVG failure to the diagonal branch (Figure A). Intravascular ultrasound (IVUS) and optical coherence tomography (OCT) showed convex calcifications at the severe proximal anastomotic stenosis (Figure B,C) and tandem stenotic sites (Figure D,E). In addition, coronary angioscopy (CAS) indicated punctate red thrombus on a protruding mass (Figure F). These findings were suggestive of calcified nodules (CN). A 3.5×48-mm stent was ...

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    12. Optical coherence tomography‐defined plaque vulnerability in relation to functional stenosis severity stratified by fractional flow reserve and quantitative flow ratio

      Optical coherence tomography‐defined plaque vulnerability in relation to functional stenosis severity stratified by fractional flow reserve and quantitative flow ratio

      Objectives We sought to investigate that the quantitative flow ratio (QFR) might be associated with optical coherence tomography (OCT)‐defined plaque vulnerability. Background Both functional stenosis severity and plaque instability are related to adverse clinical outcomes in patients with coronary artery disease. Recent studies have shown an association between physiological stenosis severity and the presence of thin‐cap fibroatheroma (TCFA). Measurement of QFR is a novel method for rapid computational estimation of fractional flow reserve (FFR). Methods We investigated 327 de novo intermediate‐to‐severe coronary lesions in 295 stable patients who underwent OCT, FFR, and QFR computation. The lesions ...

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    13. Ventricular Fibrillation During Optical Coherence Tomography/Optical Frequency Domain Imaging ― A Large Single-Center Experience ―

      Ventricular Fibrillation During Optical Coherence Tomography/Optical Frequency Domain Imaging ― A Large Single-Center Experience ―

      Abstract Background: The risks of ventricular fibrillation (Vfib) associated with frequency-domain optical coherence tomography (OCT)/optical frequency domain imaging (OFDI) remain undetermined. Methods and Results: We retrospectively studied the occurrence of Vfib during OCT/OFDI for unselected indications. The frequency of Vfib and patient and procedural characteristics were investigated. A total of 4,467 OCT/OFDI pullback examinations were performed in 1,754 patients (median of 2.0 [2.0–3.0] pullbacks for 1.0 [1.0–1.3] vessels). OCT/OFDI was performed during PCI in 899 patients (51.3%). The contrast injection volume per pullback was 14 ...

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    14. The relation between optical coherence tomography-detected layered pattern and acute side branch occlusion after provisional stenting of coronary bifurcation lesions

      The relation between optical coherence tomography-detected layered pattern and acute side branch occlusion after provisional stenting of coronary bifurcation lesions

      Background/Purpose. Layered pattern (presumed to be healed plaque after a thrombotic event) can be observed by optical coherence tomography (OCT). We sought to assess the ability of OCT-detected plaque composition to predict acute side branch (SB) occlusion after provisional bifurcation stenting. Methods This is a retrospective observational study using pre-intervention OCT in the main vessel to predict Thrombolysis in Myocardial Infarction (TIMI) flow grade ≤ 1 in a SB (diameter ≥ 1.5 mm) after provisional bifurcation stenting. OCT-detected layered pattern was defined as plaque with a superficial layer that had a different optical intensity and a clear demarcation from underlying ...

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    15. Optical Coherence Tomography–Defined Plaque Vulnerability in Relation to Functional Stenosis Severity and Microvascular Dysfunction

      Optical Coherence Tomography–Defined Plaque Vulnerability in Relation to Functional Stenosis Severity and Microvascular Dysfunction

      Objectives This study sought to investigate the relationship of unstable plaque features with physiological lesion severity and microvascular dysfunction . Background The functional severity of epicardial lesions and microvascular dysfunction are both related to adverse clinical outcomes. Methods We investigated 382 de novo intermediate and severe coronary lesions in 340 patients who underwent optical coherence tomography , fractional flow reserve (FFR), and index of microcirculatory resistance (IMR) examinations. Lesions were divided into tertiles based on either FFR or IMR values. The optical coherence tomography findings were compared among the tertiles of FFR and IMR. Each tertile was defined as follows: FFR-T1 (FFR ...

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    16. Multimodality coronary imaging to predict periprocedural myocardial necrosis after an elective percutaneous coronary intervention

      Multimodality coronary imaging to predict periprocedural myocardial necrosis after an elective percutaneous coronary intervention

      Background Although multiple imaging modalities have been tested to predict periprocedural myocardial necrosis (PMN), the superior predictive efficacy of these imaging findings has not been established fully. We sought to evaluate which findings of the coronary imaging tools would best provide predictive efficacy of PMN among optical coherence tomography (OCT), intravascular ultrasound (IVUS), and coronary computed tomography (CCT) angiography. Patients and methods A total of 130 patients with stable angina pectoris who underwent OCT, IVUS, and CCT examinations for a single de-novo preprocedural lesion were investigated. PMN was defined on the basis of two different thresholds of cardiac troponin I ...

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    17. Efficacy of Optical Coherence Tomography-derived Morphometric Assessment in Predicting the Physiological Significance of Coronary Stenosis: Head-to-Head Comparison with Intravascular Ultrasound

      Efficacy of Optical Coherence Tomography-derived Morphometric Assessment in Predicting the Physiological Significance of Coronary Stenosis: Head-to-Head Comparison with Intravascular Ultrasound

      Aims: This study aimed to investigate the diagnostic efficacy of optical coherence tomography (OCT) in identifying functional significance via fractional flow reserve (FFR) compared with that of intravascular ultrasound (IVUS). Methods and results: We investigated 203 de novo intermediate coronary lesions of 186 patients who underwent frequency-domain OCT, IVUS and FFR measurements. Diagnostic efficacy of the minimal lumen area (MLA) obtained by OCT (OCT-MLA) and IVUS (IVUS-MLA) in predicting an FFR<0.75 was evaluated. Receiver operating characteristic curve analysis showed that OCT-MLA had significantly better diagnostic efficacy than IVUS-MLA in identifying functional ischemia. OCT analysis revealed that the incidence ...

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      Mentions: Taishi Yonetsu
    18. Relationship between optical coherence tomography-derived morphological criteria and functional relevance as determined by fractional flow reserve

      Relationship between optical coherence tomography-derived morphological criteria and functional relevance as determined by fractional flow reserve

      Background Although several previous studies have indicated that optical coherence tomography (OCT)-derived minimal lumen area (MLA) correlates with fractional flow reserve (FFR) severity, other morphologic criteria for functionally significant coronary stenosis assessed by FFR have not been fully elucidated. This study aimed to identify OCT-based morphological predictors of physiologically significant ischemia assessed by FFR in angiographically intermediate coronary lesions. Methods We investigated 194 de novo intermediate coronary lesions in 178 patients with stable angina pectoris who underwent OCT imaging and FFR measurement. The lesions were divided into two groups according to an FFR threshold: ischemia group, FFR <0.75 ...

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    19. Impact of coronary plaque morphology assessed by optical coherence tomography on cardiac troponin elevation in patients with non-ST segment elevation acute coronary syndrome

      Impact of coronary plaque morphology assessed by optical coherence tomography on cardiac troponin elevation in patients with non-ST segment elevation acute coronary syndrome

      Objectives This study aimed to use optical coherence tomography (OCT) to study the relationship between plaque morphology prior to percutaneous coronary intervention (PCI) and post-PCI cardiac troponin (cTn) elevations in patients with non-ST-segment elevation acute coronary syndrome (NSTE-ACS). Furthermore, the relationship between these findings and the adverse cardiac events during follow-up was assessed. Background Association between post-PCI cTn elevations and OCT findings in NSTE-ACS patients is unclear. Methods We evaluated 167 patients with stable or falling cTn values after admission who underwent PCI. Periprocedural myocardial injury (PMI) was defined as an cTn increase of more than 70× upper limit of ...

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    20. Coronary Plaque Characteristics in Hemodialysis-Dependent Patients as Assessed by Optical Coherence Tomography

      Coronary Plaque Characteristics in Hemodialysis-Dependent Patients as Assessed by Optical Coherence Tomography

      Coronary arteries in patients with chronic kidney disease (CKD) have been shown to exhibit more extensive atherosclerosis and calcium. We aimed to assess characteristics of coronary plaque in hemodialysis (HD)-dependent patients using optical coherence tomography (OCT). This was a multicenter, retrospective study of 124 patients with stable angina who underwent OCT imaging. Sixty-two HD-dependent patients who underwent pre-intervention OCT for coronary artery disease (CAD) were compared 1:1 with a cohort of patients without CKD, matched for age, diabetes mellitus, sex, and culprit vessel. Baseline characteristics were comparable. Pre-intervention OCT imaging identified 62 paired culprit, 53 paired non-culprit, and ...

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    21. Guidewire shadow artifacts in optical coherence tomography

      Guidewire shadow artifacts in optical coherence tomography

      BACKGROUND: Because of the high resolution made possible by optical coherence tomography (OCT), previously indistinguishable guidewire artifacts are recognized during coronary imaging, and these affect image interpretation. This study aimed to assess the effect of guidewire size and structure on the artifacts produced and to introduce a novel guidewire specifically for OCT imaging that produces fewer artifacts. Elimination or minimization of guidewire artifacts supports optimal OCT imaging. METHODS: Silicon tubes simulating the coronary arteries were used to assess guidewire shadow artifacts in OCT imaging. The angles of artifacts produced by 4 types of guidewires were evaluated, including our newly designed ...

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    22. Serial examinations of right coronary artery directly injured by radiofrequency catheter ablation with optical coherence tomography and intravascular ultrasound

      Serial examinations of right coronary artery directly injured by radiofrequency catheter ablation with optical coherence tomography and intravascular ultrasound

      A 42-year-old man was referred for ablation. The origin of VT was localized close to the right coronary ostium. During ablation, the catheter tip inadvertently fell into a RCA ostium. The patient developed chest discomfort and ST-segment elevation in the inferior leads was observed. Coronary angiography confirmed severe narrowing of the ostial RCA. Stenting was deferred after satisfactory dilatation by a balloon. The patient discharged with eventless clinical course afterward. Follow-up coronary angiographic, FD-OCT, IVUS, and iMap examinations were performed at 3, 6, and 15 months after index procedure. The lesion showed progressive positive remodeling associated with intimal proliferation, medial ...

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    23. Plaque morphologies and the clinical prognosis of acute coronary syndrome caused by lesions with intact fibrous cap diagnosed by optical coherence tomography

      Plaque morphologies and the clinical prognosis of acute coronary syndrome caused by lesions with intact fibrous cap diagnosed by optical coherence tomography

      Background Pathological studies have suggested that acute coronary syndrome (ACS) may be caused by culprit lesions with intact fibrous cap (IFC), including plaque erosions. This study sought to evaluate the morphological features and clinical outcomes of patients with ACS caused by lesions with IFC. Methods A total of 318 patients with ACS who underwent optical coherence tomography (OCT) of a culprit lesion were investigated. The culprit lesions were categorized as follows: those with plaque rupture (PR group), those with an IFC (IFC group), and those with a massive thrombus precluding plaque visualization (MT group). Intravascular ultrasound (IVUS) was performed in ...

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    1-24 of 40 1 2 »
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