1. Articles from Takumi Higuma

    1-16 of 16
    1. 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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    2. 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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    3. 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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    4. 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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    5. 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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    6. Characteristics of non-culprit plaques in acute coronary syndrome patients with layered culprit plaque

      Characteristics of non-culprit plaques in acute coronary syndrome patients with layered culprit plaque

      Aims  Layered plaques represent signs of previous plaque destabilization. A recent study showed that acute coronary syndrome (ACS) patients with layered culprit plaque have more vulnerability at the culprit lesion and systemic inflammation. We aimed to compare the characteristics of non-culprit plaques between patients with or without layered plaque at the culprit lesion. We also evaluated the characteristics of layered non-culprit plaques, irrespective of culprit plaque phenotype. Methods and results We studied ACS patients who had undergone pre-intervention optical coherence tomography (OCT) imaging. The number of non-culprit lesions was evaluated on coronary angiogram and morphological characteristics of plaques were studied ...

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    7. Prasugrel versus clopidogrel for residual thrombus burden in patients with ST-segment elevation myocardial infarction: an optical coherence tomography study

      Prasugrel versus clopidogrel for residual thrombus burden in patients with ST-segment elevation myocardial infarction: an optical coherence tomography study

      Background Prasugrel was shown to inhibit platelet activity more rapidly and consistently than clopidogrel . We compared the effects of prasugrel and clopidogrel on residual thrombus burden assessed by optical coherence tomography after stent implantation in patients with ST-segment elevation myocardial infarction (STEMI). Patients and methods A total of 76 patients with STEMI undergoing percutaneous coronary intervention (PCI) within 12 h after the onset were retrospectively enrolled. Of them, 34 patients were treated with prasugrel (loading dose, 20 mg) and the remaining 42 with clopidogrel (loading dose, 300 mg). Stent volume and in-stent thrombus volume were assessed by post-PCI optical coherence ...

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    8. SYNTAX Score, and Pre- and Post-Stent Optical Coherence Tomography Findings in the Left Anterior Descending Coronary Artery in Patients with Stable Angina Pectoris

      SYNTAX Score, and Pre- and Post-Stent Optical Coherence Tomography Findings in the Left Anterior Descending Coronary Artery in Patients with Stable Angina Pectoris

      SYNTAX score (SS) has been reported to be an independent predictor of future cardiac events including target lesion revascularization (TLR). The aim of this study was to assess the relationship between SS and plaque characteristics and post-stent vascular response using optical coherence tomography (OCT) in coronary artery tree and left anterior descending artery (LAD) in patients with stable angina. A total of 179 lesions among 165 patients, including 100 lesions in LAD, were analyzed. Patients were stratified into tertiles. In pre-PCI analysis of whole coronary tree and LAD, lesions of the 3 rd tertile had the highest prevalence of lipid ...

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    9. SYNTAX Score and Pre- and Poststent Optical Coherence Tomography Findings in the Left Anterior Descending Coronary Artery in Patients With Stable Angina Pectoris

      SYNTAX Score and Pre- and Poststent Optical Coherence Tomography Findings in the Left Anterior Descending Coronary Artery in Patients With Stable Angina Pectoris

      SYNTAX score (SS) has been reported to be an independent predictor of future cardiac events including target lesion revascularization. The aim of this study was to assess the relation between SS and plaque characteristics and poststent vascular response using optical coherence tomography in coronary artery tree and left anterior descending artery (LAD) in patients with stable angina. A total of 179 lesions among 165 patients, including 100 lesions in LAD, were analyzed. Patients were stratified into tertiles. In pre–percutaneous coronary intervention analysis of whole coronary tree and LAD, lesions of the third tertile had the highest prevalence of lipid-rich ...

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    10. Clinical Significance of Lipid-Rich Plaque Detected by Optical Coherence Tomography : A 4-Year Follow-Up Study

      Clinical Significance of Lipid-Rich Plaque Detected by Optical Coherence Tomography : A 4-Year Follow-Up Study

      Background Lipid-rich plaque (LRP) is thought to be a precursor to cardiac events. However, its clinical significance in coronary arteries has never been systematically investigated. Objectives This study investigated the prevalence and clinical significance of LRP in the nonculprit region of the target vessel in patients undergoing percutaneous coronary intervention (PCI). Methods The study included 1,474 patients from 20 sites across 6 countries undergoing PCI, who had optical coherence tomography (OCT) imaging of the target vessel. Major adverse cardiac events (MACE) were defined as a composite of cardiac death, acute myocardial infarction, and ischemia-driven revascularization. Patients were followed for ...

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    11. Does Residual Thrombus After Aspiration Thrombectomy Affect the Outcome of Primary PCI in Patients With ST-Segment Elevation Myocardial Infarction? An Optical Coherence Tomography Study

      Does Residual Thrombus After Aspiration Thrombectomy Affect the Outcome of Primary PCI in Patients With ST-Segment Elevation Myocardial Infarction? An Optical Coherence Tomography Study

      Objectives The aim of this study was to evaluate if residual thrombus burden after aspiration thrombectomy affects the outcomes of primary percutaneous coronary intervention in patients with ST-segment elevation myocardial infarction (STEMI). Background Recent studies failed to show clinical benefit of aspiration thrombectomy in STEMI patients. This might be due to insufficient removal of thrombus at the culprit lesion. Methods A total of 109 STEMI patients who underwent aspiration thrombectomy followed by stenting within 24 h from symptom onset were included. Optical coherence tomography was performed after thrombectomy to measure residual thrombus burden. Patients were divided into tertiles based on ...

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    12. Coronary Plaque Characteristics Associated With Reduced TIMI (Thrombolysis in Myocardial Infarction) Flow Grade in Patients With ST-Segment–Elevation Myocardial Infarction A Combined Optical Coherence Tomography and Intravascular Ultrasound Study

      Coronary Plaque Characteristics Associated With Reduced TIMI (Thrombolysis in Myocardial Infarction) Flow Grade in Patients With ST-Segment–Elevation Myocardial Infarction A Combined Optical Coherence Tomography and Intravascular Ultrasound Study

      Background— Previous studies reported that reduced TIMI (Thrombolysis in Myocardial Infarction) flow grade before procedure was associated with worse clinical outcomes in patients with ST-segment–elevation myocardial infarction undergoing primary percutaneous coronary intervention. The aim of this study was to identify specific morphological characteristics of the culprit plaque associated with poor TIMI flow grade at baseline in patients with ST-segment–elevation myocardial infarction using both optical coherence tomography and intravascular ultrasound. Methods and Results— A total of 111 ST-segment–elevation myocardial infarction patients who underwent percutaneous coronary intervention within 24 hours of symptom onset were included. Both optical coherence tomography ...

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    13. Coronary Plaque Characteristics Associated With Reduced TIMI (Thrombolysis in Myocardial Infarction) Flow Grade in Patients With ST-Segment–Elevation Myocardial Infarction A Combined Optical Coherence Tomography and Intravascular Ultrasound Study

      Coronary Plaque Characteristics Associated With Reduced TIMI (Thrombolysis in Myocardial Infarction) Flow Grade in Patients With ST-Segment–Elevation Myocardial Infarction A Combined Optical Coherence Tomography and Intravascular Ultrasound Study

      Background— Previous studies reported that reduced TIMI (Thrombolysis in Myocardial Infarction) flow grade before procedure was associated with worse clinical outcomes in patients with ST-segment–elevation myocardial infarction undergoing primary percutaneous coronary intervention. The aim of this study was to identify specific morphological characteristics of the culprit plaque associated with poor TIMI flow grade at baseline in patients with ST-segment–elevation myocardial infarction using both optical coherence tomography and intravascular ultrasound. Methods and Results— A total of 111 ST-segment–elevation myocardial infarction patients who underwent percutaneous coronary intervention within 24 hours of symptom onset were included. Both optical coherence tomography ...

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    14. Coronary Calcification and Plaque Vulnerability An Optical Coherence Tomographic Study

      Coronary Calcification and Plaque Vulnerability An Optical Coherence Tomographic Study

      Background— Spotty superficial calcium deposits have been implicated in plaque vulnerability based on previous intravascular imaging studies. Biomechanical models suggest that microcalcifications between 5 and 65 µm in diameter can intensify fibrous cap stress, promoting plaque rupture. However, the 100- to 200-µm resolution of intravascular ultrasound limits its ability to discriminate single calcium deposits from clusters of smaller deposits, and a previous optical coherence tomographic investigation evaluated calcifications within a long segment of artery, which may not truly reflect the mechanics involved in potentiating focal plaque rupture. Methods and Results— Detailed optical coherence tomographic assessment of coronary calcification at ...

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    15. A Combined Optical Coherence Tomography and Intravascular Ultrasound Study on Plaque Rupture, Plaque Erosion, and Calcified Nodule in Patients With ST-Segment Elevation Myocardial Infarction : Incidence, Morphologic Characteristics, and Outcomes After Per

      A Combined Optical Coherence Tomography and Intravascular Ultrasound Study on Plaque Rupture, Plaque Erosion, and Calcified Nodule in Patients With ST-Segment Elevation Myocardial Infarction : Incidence, Morphologic Characteristics, and Outcomes After Per

      Objectives This study sought to evaluate the incidence of plaque rupture (PR), plaque erosion (PE), and calcified nodule (CN) using optical coherence tomography (OCT) in patients with ST-segment elevation myocardial infarction (STEMI); to compare detailed morphologic plaque characteristics of PR, PE, and CN with optical coherence tomography and intravascular ultrasound; and to compare the post-procedure outcomes among PR, PE, and CN. Background The incidence and detailed morphologic characteristics of PR, PE, and CN in STEMI patients and their outcome after percutaneous coronary intervention (PCI) are unknown. Methods A total of 112 STEMI patients who underwent PCI within 12 h from ...

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    16. Stent malapposition, as a potential mechanism of very late stent thrombosis after bare-metal stent implantation: A case report

      Stent malapposition, as a potential mechanism of very late stent thrombosis after bare-metal stent implantation: A case report

      A 90-year-old man was admitted to our hospital with acute ST-segment elevation myocardial infarction. He had a history of post-infarction angina pectoris 79 months ago and had a bare-metal stent (BMS) implanted in the proximal left anterior descending artery at our hospital. Emergent coronary angiography demonstrated thrombotic occlusion in the previously stented segment. After catheter thrombectomy, antegrade flow was restored, but 90% stenosis with haziness persisted in the proximal and distal portions of the previously stented segment. Intravascular ultrasound imaging showed interstrut cavities or stent malapposition at the proximal and distal sites of stented segment. In close proximity to the ...

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    1-16 of 16
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    Stent malapposition, as a potential mechanism of very late stent thrombosis after bare-metal stent implantation: A case report A Combined Optical Coherence Tomography and Intravascular Ultrasound Study on Plaque Rupture, Plaque Erosion, and Calcified Nodule in Patients With ST-Segment Elevation Myocardial Infarction : Incidence, Morphologic Characteristics, and Outcomes After Per Coronary Calcification and Plaque Vulnerability An Optical Coherence Tomographic Study Coronary Plaque Characteristics Associated With Reduced TIMI (Thrombolysis in Myocardial Infarction) Flow Grade in Patients With ST-Segment–Elevation Myocardial Infarction A Combined Optical Coherence Tomography and Intravascular Ultrasound Study Coronary Plaque Characteristics Associated With Reduced TIMI (Thrombolysis in Myocardial Infarction) Flow Grade in Patients With ST-Segment–Elevation Myocardial Infarction A Combined Optical Coherence Tomography and Intravascular Ultrasound Study Does Residual Thrombus After Aspiration Thrombectomy Affect the Outcome of Primary PCI in Patients With ST-Segment Elevation Myocardial Infarction? An Optical Coherence Tomography Study Clinical Significance of Lipid-Rich Plaque Detected by Optical Coherence Tomography : A 4-Year Follow-Up Study SYNTAX Score, and Pre- and Post-Stent Optical Coherence Tomography Findings in the Left Anterior Descending Coronary Artery in Patients with Stable Angina Pectoris SYNTAX Score and Pre- and Poststent Optical Coherence Tomography Findings in the Left Anterior Descending Coronary Artery in Patients With Stable Angina Pectoris COMPARISON OF POST STENT OPTICAL COHERENCE TOMOGRAPHY FINDINGS AMONG THREE SUBTYPES OF CALCIFIED CULPRIT PLAQUES IN PATIENTS WITH ACUTE CORONARY SYNDROME Full-range space-division multiplexing optical coherence tomography angiography Measuring 3D Optic Nerve Head Deformations using Digital Volume Correlation of in vivo Optical Coherence Tomography Data (Thesis)