1. Articles from renu virmani

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    1. Algorithmic Approach for Optical Coherence Tomography–Guided Stent Implantation During Percutaneous Coronary Intervention

      Algorithmic Approach for Optical Coherence Tomography–Guided Stent Implantation During Percutaneous Coronary Intervention

      Intravascular imaging plays a key role in optimizing outcomes for percutaneous coronary intervention (PCI). Optical coherence tomography (OCT) utilizes a user-friendly interface and provides high-resolution images. OCT can be used as part of daily practice in all stages of a coronary intervention: baseline lesion assessment, stent selection, and stent optimization. Incorporating a standardized, algorithmic approach when using OCT allows for precision PCI.

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    2. Quantitative measurement of lipid rich plaque by coronary computed tomography angiography: A correlation of histology in sudden cardiac death

      Quantitative measurement of lipid rich plaque by coronary computed tomography angiography: A correlation of histology in sudden cardiac death

      Background and aims Recent advancements in coronary computed tomography angiography (CCTA) have allowed for the quantitative measurement of high-risk lipid rich plaque. Determination of the optimal threshold for Hounsfield units (HU) by CCTA for identifying lipid rich plaque remains unknown. We aimed to validate reliable cut-points of HU for quantitative assessment of lipid rich plaque. Methods 8 post-mortem sudden coronary death hearts were evaluated with CCTA and histologic analysis. Quantitative plaque analysis was performed in histopathology images and lipid rich plaque area was defined as intra-plaque necrotic core area. CCTA images were analyzed for quantitative plaque measurement. Low attenuation plaque ...

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      Mentions: Renu Virmani
    3. Are characteristics of plaque erosion defined by optical coherence tomography similar to true erosion in pathology?

      Are characteristics of plaque erosion defined by optical coherence tomography similar to true erosion in pathology?

      Plaque erosion occurs without cap disruption where flowing blood comes into direct contact with intimal surface lacking endothelial cells. 1 In both clinical studies using intravascular imaging and autopsy data from subjects dying suddenly, plaque erosion is the second most common cause of coronary thrombus. In our recent pathological analysis of autopsies from subjects dying suddenly, plaque rupture was the most frequent causes of coronary thrombus (60%), the second most frequent was...

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    4. Histopathological Differential Diagnosis of Optical Coherence Tomographic Image Interpretation After Stenting

      Histopathological Differential Diagnosis of Optical Coherence Tomographic Image Interpretation After Stenting

      Objectives The aim of this study was to identify histological features that correlate with terms commonly used to describe optical coherence tomographic (OCT) and optical frequency-domain imaging (OFDI) images of stented vessels, by means of a histopathological validation study using stented human coronary arteries. Background OCT imaging and OFDI are used to evaluate vascular responses to stent implantation. Descriptive terms such as “peristrut low attenuation” and “heterogeneous” have been used to describe neointimal characteristics that may have clinical relevance. However, only limited histopathological correlations are available. Methods Using the CVPath stent registry, 19 cases were identified in whom implantation duration ...

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    5. Optimization of coronary optical coherence tomography imaging using the attenuation-compensated technique: a validation study

      Optimization of coronary optical coherence tomography imaging using the attenuation-compensated technique: a validation study

      Purpose To optimize conventional coronary optical coherence tomography (OCT) images using the attenuation-compensated technique to improve identification of plaques and the external elastic lamina (EEL) contour. Method The attenuation-compensated technique was optimized via manipulating contrast exponent C, and compression exponent N, to achieve an optimal contrast and signal-to-noise ratio (SNR). This was applied to 60 human coronary lesions (38 native and 22 stented) ex vivo conventional coronary OCT images acquired from heart autopsies of 10 patients and matching histology was available as reference. Three independent reviewers assessed the conventional and attenuation-compensated OCT images blindly for plaque characteristics and EEL detection ...

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    6. Bioresorption and Vessel Wall Integration of a Fully Bioresorbable Polymeric Everolimus-Eluting Scaffold Optical Coherence Tomography, Intravascular Ultrasound, and Histological Study in a Porcine Model With 4-Year Follow-Up

      Bioresorption and Vessel Wall Integration of a Fully Bioresorbable Polymeric Everolimus-Eluting Scaffold Optical Coherence Tomography, Intravascular Ultrasound, and Histological Study in a Porcine Model With 4-Year Follow-Up

      Objectives The aim of the present study was to investigate the relationship between the integration process and luminal enlargement with the support of light intensity (LI) analysis on optical coherence tomography (OCT), echogenicity analysis on intravascular ultrasound, and histology up to 4 years in a porcine model. Background In pre-clinical and clinical studies, late luminal enlargement has been demonstrated at long-term follow-up after everolimus-eluting poly-l-lactic acid coronary scaffold implantation. However, the time relationship and the mechanistic association with the integration process are still unclear. Methods Seventy-three nonatherosclerotic swine that received 112 Absorb scaffolds were evaluated in vivo by OCT, intravascular ...

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    7. Malapposition: is it a major cause of stent thrombosis?

      Malapposition: is it a major cause of stent thrombosis?

      Stent thrombosis (ST) is a devastating complication associated with a high morbidity and mortality in patients who have undergone percutaneous coronary intervention (PCI) for coronary heart disease (CHD). In-hospital mortalities of patients suffering from ST have been reported to be as high as 7.9% for acute ST (AST; occurring <24 h after PCI) and subacute ST (SAST; occurring within 30 days after PCI), 3.8% for late ST (LST; occurring within the first year after PCI), and 3.6% for very late ST (VLST; occurring 1 year after PCI). 1 Recently, longer duration (30 months) of dual antiplatelet therapy ...

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    8. Are Microcalcification and Hemosiderin Really Limitations of OCT in Detection of TCFA?

      Are Microcalcification and Hemosiderin Really Limitations of OCT in Detection of TCFA?

      With great interest, we read the recent work by Fujii et al. (1) published in iJACC reporting the diagnostic accuracy of optical coherence tomography (OCT) and grayscale intravascular ultrasound for the detection of coronary thin cap fibroatheroma (TCFA) with histologic validation in human autopsy hearts. In this publication, Fujii et al. (1) documented a limited capability of OCT and intravascular ultrasound for TCFA identification when each imaging device was solely utilized. The authors attributed the low accuracy of OCT in TCFA detection to 4 reasons: presence of foam cell macrophage, microcalcification, hemosiderin accumulation, and organizing thrombus inclusive of fibrin. However ...

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    9. The Mystery of Spotty Calcification Can We Solve It by Optical Coherence Tomography?

      The Mystery of Spotty Calcification Can We Solve It by Optical Coherence Tomography?

      Spotty calcification has recently been introduced as a marker of plaque vulnerability in patients presenting with acute coronary syndrome undergoing invasive and noninvasive coronary imaging, 1 and it has been suggested to be of predictive value for percent atheroma volume with greater progression. 2 Several pathological and clinical studies applying computed tomography (CT) and intravascular ultrasound (IVUS) demonstrated that spotty calcification is more frequently observed in lesions with plaque rupture compared with stable plaque. 3 , 4 Recently, optical coherence tomography (OCT) has emerged as the premier intracoronary imaging technology with a higher resolution (10–20 μm) than IVUS (100–200 ...

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    10. Neoatherosclerosis: mirage of an ancient illness or genuine disease condition?

      Neoatherosclerosis: mirage of an ancient illness or genuine disease condition?

      In-stent neoatherosclerosis has become the darling of the interventional cardiology community and is blamed for most stent thrombosis (ST) occurring late after drug-eluting stent (DES) implantation. Neoatherosclerosis accounted for only 33% of late and very late ST at autopsy following implantation of first-generation DES. 1 However, the clinical prevalence of neoatherosclerosis and its percentage of cases presenting with late and very late ST remains unknown. In the current issue of the journal, Taniwaki et al . propose a significant and biologically relevant association between the presence of in-stent neoatherosclerosis and the progression of native atherosclerosis in a cohort of 88 patients ...

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    11. The coronary substrate determines prognosis in acute coronary syndromes: the kaleidoscope has been shaken ... again!

      The coronary substrate determines prognosis in acute coronary syndromes: the kaleidoscope has been shaken ... again!

      The identification of ‘vulnerable’ or ‘high risk’ coronary plaques has represented the quest for the Holy Grail in interventional cardiology for the past three decades. Plaque rupture (PR), plaque erosion (PE), and complicated calcified nodules (CNs) constitute the most common underlying substrates leading to coronary thrombosis and acute coronary syndromes (ACS). 1 – 3 Despite the advent of novel intracoronary imaging techniques, which are able to disclose unique morphological insights and plaque features similar to those found in plaques already complicated with coronary thrombosis, their value in predicting future clinical events remains limited. 4 – 7 Optical coherence tomography (OCT) is an ...

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    12. Neoatherosclerosis: overview of histopathologic findings and implications for intravascular imaging assessment

      Neoatherosclerosis: overview of histopathologic findings and implications for intravascular imaging assessment

      Despite the reduction in late thrombotic events with newer-generation drug-eluting stents (DES), late stent failure remains a concern following stent placement. In-stent neoatherosclerosis has emerged as an important contributing factor to late vascular complications including very late stent thrombosis and late in-stent restenosis. Histologically, neoatherosclerosis is characterized by accumulation of lipid-laden foamy macrophages within the neointima with or without necrotic core formation and/or calcification. The development of neoatherosclerosis may occur in months to years following stent placement, whereas atherosclerosis in native coronary arteries develops over decades. Pathologic and clinical imaging studies have demonstrated that neoatherosclerosis occurs more frequently and ...

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    13. Hypersensitivity Reaction in the US Food and Drug Administration-Approved Second-Generation Drug-Eluting Stents: Histopathological Assessment With Ex Vivo Optical Coherence Tomography

      Hypersensitivity Reaction in the US Food and Drug Administration-Approved Second-Generation Drug-Eluting Stents: Histopathological Assessment With Ex Vivo Optical Coherence Tomography

      A 55-year-old white man received 4 coronary stents, 3 Resolute zotarolimus-eluting stents (R-ZES; Medtronic, Santa Rosa, CA) and 1 XIENCE Xpedition (CoCr-EES; Abbott Vascular, Santa Clara, CA), for unstable angina pectoris 238 days antemortem. The patient was found dead and had recently been seen without any complaints. The patient had a history of hypertension, hyperlipidemia, and smoking. At the time of stent placement, coronary angiography revealed diffuse disease in the left anterior descending artery (LAD) with severe stenosis of the proximal LAD and moderate to severe stenosis of the mid LAD. Percutaneous coronary intervention was carried out, and 4 overlapping ...

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    14. Matching human pathology is essential for validating OCT imaging to detect high-risk plaques

      Matching human pathology is essential for validating OCT imaging to detect high-risk plaques

      We thank Mark Brezinski for his Correspondence ( Capabilities, limitations, and misconceptions of using OCT to assess vulnerable plaques . Nat. Rev. Cardiol. doi:10.1038/nrcardio.2014.62-c1 ) 1 on our Review ( Clinical classification of plaque morphology in coronary disease . Nat. Rev. Cardiol. 11 , 379 – 389 ; 2014 ), 2 and for his comments and clarifications. We agree that the phenomenon

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    15. Mechanisms of Atherothrombosis and Vascular Response to Primary Percutaneous Coronary Intervention in Women Versus Men With Acute Myocardial Infarction : Results of the OCTAVIA (Optical Coherence Tomography Assessment of Gender Diversity in Primary Angiop

      Mechanisms of Atherothrombosis and Vascular Response to Primary Percutaneous Coronary Intervention in Women Versus Men With Acute Myocardial Infarction : Results of the OCTAVIA (Optical Coherence Tomography Assessment of Gender Diversity in Primary Angiop

      Objectives This study sought to assess in vivo sex differences in the pathophysiology of ST-segment elevation myocardial infarction (STEMI) and vascular response to primary percutaneous coronary intervention (PCI). Background There is no consensus on whether differences in the pathophysiology of STEMI and response to primary PCI between women and men reflect biological factors as opposed to differences in age. Methods In this prospective, multicenter study, 140 age-matched men and women with STEMI undergoing primary PCI with everolimus-eluting stent were investigated with intravascular optical coherence tomography, histopathology-immunohistochemistry of thrombus aspirates, and serum biomarkers. Primary endpoints were the percentages of culprit plaque ...

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    16. Clinical classification of plaque morphology in coronary disease

      Clinical classification of plaque morphology in coronary disease

      In published post-mortem pathological studies, more than two-thirds of acute coronary events are associated with the rupture of lipid-rich, voluminous, and outwardly remodelled plaques covered by attenuated and inflamed fibrous caps in the proximal part of coronary arteries. Superficial erosion of the plaques is responsible for most of the remaining events; the eroded plaques usually do not demonstrate much lipid burden, do not have thin fibrous caps, are not positively remodelled, and are not critically occlusive. Both noninvasive and invasive imaging studies have been performed to clinically define the plaque characteristics in acute coronary syndromes in an attempt to identify ...

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    17. Expectations and limitations of contemporary intravascular imaging: lessons learned from pathology

      Expectations and limitations of contemporary intravascular imaging: lessons learned from pathology

      Acute coronary syndrome is the leading cause of death worldwide and plaque rupture is the most common underlying mechanism of coronary thrombosis. During the last 2 decades the understanding of atherosclerotic plaque progression advanced dramatically and pathology studies provided fundamental insights of underlying plaque morphology, which paved the way for invasive imaging modalities, which bring a new area of atherosclerotic plaque characterization in vivo. The development of intravascular ultrasound (IVUS) allowed the field to evaluate the principles of vascular anatomy, which is often underestimated by coronary angiography. Furthermore, IVUS image technologies were developed to obtain improved characterization of plaque composition ...

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    18. Clinical use of Optical Coherence Tomography to identify angiographic silent stent thrombosis

      Clinical use of Optical Coherence Tomography to identify angiographic silent stent thrombosis

      Objectives: Patients previously treated with coronary stents may suffer an acute coronary syndrome (ACS) without any evidence of thrombus formation on coronary angiography (CAG). This may be due to partial, non-occlusive stent thrombosis with microembolization. In this paper we illustrate possible mechanisms both with Optical coherence tomography (OCT) and histology. Design: We present two cases with ACS from very late stent thrombosis, both previously treated with first generation drug eluting stents (DES). Results: The first patient had ACS 15 months after DES implantation. The angiogram (CAG) was near normal with slight peri-stent contrast staining. OCT revealed abnormalities including thrombus not ...

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    19. Computational Fluid Dynamics Simulations of Hemodynamics in Plaque Erosion

      Computational Fluid Dynamics Simulations of Hemodynamics in Plaque Erosion

      We investigated whether local hemodynamics were associated with sites of plaque erosion and hypothesized that patients with plaque erosion have locally elevated WSS magnitude in regions where erosion has occurred. We generated 3D, patient-specific models of coronary arteries from biplane angiographic images in 3 human patients with plaque erosion diagnosed by optical coherence tomography. Using computational fluid dynamics, we simulated pulsatile blood flow and calculated both wall shear stress (WSS) and oscillatory shear index (OSI). We also investigated anatomic features of plaque erosion sites by examining branching and local curvature in X-ray angiograms of barium-perfused autopsy hearts. Neither high nor ...

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    20. Increased Thin-Cap Neoatheroma and Periprocedural Myocardial Infarction in Drug-Eluting Stent Restenosis Multimodality Intravascular Imaging of Drug-Eluting and Bare-Metal Stents

      Increased Thin-Cap Neoatheroma and Periprocedural Myocardial Infarction in Drug-Eluting Stent Restenosis  Multimodality Intravascular Imaging of Drug-Eluting and Bare-Metal Stents

      Background— Re-endothelialization is delayed after drug-eluting stent (DES) implantation. In this setting, neointima is more prone to become lipid laden and develop neoatherosclerosis (NA), potentially increasing plaque vulnerability. Methods and Results— Optical coherence tomography and near-infrared spectroscopy with intravascular ultrasound were used to characterize NA in 65 (51 DES and 14 bare-metal stents) consecutive symptomatic patients with in-stent restenosis. Median duration poststent implantation was 33 months. Optical coherence tomography–verified NA was observed in 40 stents with in-stent restenosis (62%), was more prevalent in DES than bare-metal stents (68% versus 36%; P =0.02), and demonstrated significantly higher prevalence of ...

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    21. Feature Of The Week 8/4/13: MGH OCT Registry Reports on In Vivo OCT Studies of Plaque Erosion and Calcified Nodule In Acute Coronary Syndrome

      Feature Of The Week 8/4/13: MGH OCT Registry Reports on In Vivo OCT Studies of Plaque Erosion and Calcified Nodule In Acute Coronary Syndrome

      Pathology studies reported that three most common causes of acute coronary syndrome (ACS) or sudden cardiac death are plaque rupture, plaque erosion and calcified nodules. The morphological and clinical characteristics of the underlying pathology of ACS, especially plaque erosion and calcified nodule, have never been well studied in vivo. Using optical coherence tomography, we found that plaque erosions are the substrate for ACS in 31% of patients and calcified nodules in 8% of patients, which are consistent with pathological findings. Erosions are more likely to cause non-ST-segment elevation ACS than ST-segment elevation myocardial infarction. Compared to plaque rupture, plaque erosion ...

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    22. In Vivo Diagnosis of Plaque Erosion and Calcified Nodule in Patients with Acute Coronary Syndrome by Intravascular Optical Coherence Tomography

      In Vivo Diagnosis of Plaque Erosion and Calcified Nodule in Patients with Acute Coronary Syndrome by Intravascular Optical Coherence Tomography

      Objectives To characterize the morphological features of plaque erosion and calcified nodule in patients with acute coronary syndrome (ACS) by optical coherence tomography (OCT). Background Plaque erosion and calcified nodule have not been systematically investigated in vivo . Methods One hundred and twenty-six patients with ACS who had undergone pre-intervention OCT imaging were included. The culprit lesions were classified as plaque rupture (PR), erosion (OCT-erosion), calcified nodule (OCT-CN), or others using a new set of diagnostic criteria for OCT. Results The incidences of PR, OCT-erosion, and OCT-CN were 43.7%, 31.0%, and 7.9%, respectively. Patients with OCT-erosion were the ...

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    23. Intracoronary Optical Coherence Tomography and Histology of Overlapping Everolimus-Eluting Bioresorbable Vascular Scaffolds in a Porcine Coronary Artery Model : The Potential Implications for Clinical Practice

      Intracoronary Optical Coherence Tomography and Histology of Overlapping Everolimus-Eluting Bioresorbable Vascular Scaffolds in a Porcine Coronary Artery Model : The Potential Implications for Clinical Practice

      Objectives This study sought to assess the vascular response of overlapping Absorb stents compared with overlapping newer-generation everolimus-eluting metallic platform stents (Xience V [XV]) in a porcine coronary artery model. Background The everolimus-eluting bioresorbable vascular scaffold (Absorb) is a novel approach to treating coronary lesions. A persistent inflammatory response, fibrin deposition, and delayed endothelialization have been reported with overlapping first-generation drug-eluting stents. Methods Forty-one overlapping Absorb and overlapping Xience V (XV) devices (3.0 × 12 mm) were implanted in the main coronary arteries of 17 nonatherosclerotic pigs with 10% overstretch. Implanted coronary arteries were evaluated by optical coherence tomography (OCT ...

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