1. Articles from Juan Luis Gutiérrez-Chico

    1-24 of 35 1 2 »
    1. Risk Stratification in Acute Coronary Syndrome by Comprehensive Morphofunctional Assessment With Optical Coherence Tomography

      Risk Stratification in Acute Coronary Syndrome by Comprehensive Morphofunctional Assessment With Optical Coherence Tomography

      Background: Artificial intelligence enables simultaneous evaluation of plaque morphology and computational physiology from optical coherence tomography (OCT). Objectives: This study sought to appraise the predictive value of major adverse cardiovascular events (MACE) by combined plaque morphology and computational physiology. Methods: A total of 604 patients with acute coronary syndrome who underwent OCT imaging in ≥1 nonculprit vessel during index coronary angiography were retrospectively enrolled. A novel morphologic index, named the lipid-to-cap ratio (LCR), and a functional parameter to evaluate the physiologic significance of coronary stenosis from OCT, namely, the optical flow ratio (OFR), were calculated from OCT, together with classical ...

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    2. Radial wall strain: a novel angiographic measure of plaque composition and vulnerability

      Radial wall strain: a novel angiographic measure of plaque composition and vulnerability

      Background: The lipid-to-cap ratio (LCR) and thin-cap fibroatheroma (TCFA) derived from optical coherence tomography (OCT) are indicative of plaque vulnerability. Aims: We aimed to explore the association of a novel method to estimate radial wall strain (RWS) from angiography with plaque composition and features of vulnerability assessed by OCT. Methods: Anonymised data from patients with intermediate stenosis who underwent coronary angiography (CAG) and OCT were analysed in a core laboratory. Angiography-derived RWS max was computed as the maximum deformation of lumen diameter throughout the cardiac cycle, expressed as a percentage of the largest lumen diameter. The LCR and TCFA were ...

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    3. Artificial intelligence and optical coherence tomography for the automatic characterisation of human atherosclerotic plaques

      Artificial intelligence and optical coherence tomography for the automatic characterisation of human atherosclerotic plaques

      Background: Intravascular optical coherence tomography (IVOCT) enables detailed plaque characterisation in vivo , but visual assessment is time-consuming and subjective. Aims: This study aimed to develop and validate an automatic framework for IVOCT plaque characterisation using artificial intelligence (AI). Methods: IVOCT pullbacks from five international centres were analysed in a core lab, annotating basic plaque components, inflammatory markers and other structures. A deep convolutional network with encoding-decoding architecture and pseudo-3D input was developed and trained using hybrid loss. The proposed network was integrated into commercial software to be externally validated on additional IVOCT pullbacks from three international core labs, taking the ...

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    4. Optical Coherence Tomography-Derived Changes in Plaque Structural Stress Over the Cardiac Cycle: A New Method for Plaque Biomechanical Assessment

      Optical Coherence Tomography-Derived Changes in Plaque Structural Stress Over the Cardiac Cycle: A New Method for Plaque Biomechanical Assessment

      Introduction: Cyclic plaque structural stress has been hypothesized as a mechanism for plaque fatigue and eventually plaque rupture. A novel approach to derive cyclic plaque stress in vivo from optical coherence tomography (OCT) is hereby developed. Materials and Methods: All intermediate lesions from a previous OCT study were enrolled. OCT cross-sections at representative positions within each lesion were selected for plaque stress analysis. Detailed plaque morphology, including plaque composition, lumen and internal elastic lamina contours, were automatically delineated. OCT-derived vessel and plaque morphology were included in a 2-dimensional finite element analysis, loaded with patient-specific intracoronary pressure tracing data, to calculate ...

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    5. Comprehensive appraisal of cardiac motion artefact in optical coherence tomography

      Comprehensive appraisal of cardiac motion artefact in optical coherence tomography

      Background: The relation between cardiac motion artefact (CMA) in optical coherence tomography (OCT) and the phases of cardiac cycle is unclear. Methods: Optical coherence tomography pullbacks containing metallic stents were co-registered with angiography and retrospectively analyzed. The beginning of three phases, namely ejection, rapid-inflow and diastasis, was identified in angiography. Rotation, shortening, elongation and repetition were qualitatively labelled as CMA artefacts. Platforms with coaxial longitudinal connectors (ML8 and Magmaris) entered a quantitative sub-study, consisting of measuring the length of their connector at the beginning of each phase. Results: A total of 261 stents (127 patients) were analyzed, including 105 stents ...

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    6. Automatic Coregistration Between Coronary Angiography and Intravascular Optical Coherence Tomography

      Automatic Coregistration Between Coronary Angiography and Intravascular Optical Coherence Tomography

      This study sought to evaluate a novel approach for automatic coregistration of optical coherence tomography (OCT) and coronary angiography. Lumen diameters and side branches from both coronary angiography and OCT were used to create 2 feature sets. Subsequently, a 2-step coregistration approach was performed on the feature sets for matching of each OCT cross section on the angiographic centerline. For validation, all side branches with 1.0 mm diameter were identi fied and used as paired fiduciary landmarks. Geographical error was de fi ned as the distance between the automatically coregistered and the true-paired landmarks. Altogether 212 vessels from 181 ...

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    7. Automatic Characterisation of Human Atherosclerotic Plaque Composition from Intravascular Optical Coherence Tomography Using Artificial Intelligence

      Automatic Characterisation of Human Atherosclerotic Plaque Composition from Intravascular Optical Coherence Tomography Using Artificial Intelligence

      Background Intravascular optical coherence tomography (IVOCT) enables detailed plaque characterisation in-vivo, but visual assessment is time-consuming and subjective. Aims This study aims to develop and validate an automatic framework for IVOCT plaque characterisation using artificial intelligence (AI). Methods IVOCT pullbacks from 5 international centres were analysed in a corelab, annotating basic plaque components, inflammatory markers and other structures. A deep convolutional network with encoding-decoding architecture and pseudo-3D input was developed and trained using hybrid loss. The proposed network was integrated into commercial software to be externally validated on additional IVOCT pullbacks from three international corelabs, taking the consensus among corelabs ...

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    8. Identification of the type of stent with three-dimensional optical coherence tomography: the SPQR study

      Identification of the type of stent with three-dimensional optical coherence tomography: the SPQR study

      Background: The ability of optical coherence tomography (OCT) to identify specific types of stent has never been systematically studied. Methods and results: A series of 212 consecutive patients with OCT from six international centres were retrospectively screened, finding 294 metallic stents or scaffolds in 146 patients. The sample was analysed by two blinded operators, applying a dedicated protocol in 4 steps to identify the type of stent: 1) 3D and automatic strut detection (ASD), 2) 3D tissue view, 3) Longitudinal view with ASD, 4) Mode “stent only” and ASD. The protocol correctly identified 285 stents (96.9%, kappa 0.965 ...

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    9. Automatic stent reconstruction in optical coherence tomography based on a deep convolutional model

      Automatic stent reconstruction in optical coherence tomography based on a deep convolutional model

      Intravascular optical coherence tomography (IVOCT) can accurately assess stent apposition and expansion, thus enabling the optimisation of a stenting procedure to minimize the risk of device failure. This paper presents a deep convolutional based model for automatic detection and segmentation of stent struts. The input of pseudo-3D images aggregated the information from adjacent frames to refine the probability of strut detection. In addition, multi-scale shortcut connections were implemented to minimize the loss of spatial resolution and refine the segmentation of strut contours. After training, the model was independently tested in 21,363 cross-sectional images from 170 IVOCT image pullbacks. The ...

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    10. Diagnostic accuracy and reproducibility of optical flow ratio for functional evaluation of coronary stenosis in a prospective series

      Diagnostic accuracy and reproducibility of optical flow ratio for functional evaluation of coronary stenosis in a prospective series

      Background: Evaluating prospectively the feasibility, accuracy and reproducibility of optical flow ratio (OFR), a novel method of computational physiology based on optical coherence tomography (OCT). Methods and results: Sixty consecutive patients (76 vessels) underwent prospectively OCT, angiography-based quantitative flow ratio (QFR) and fractional flow ratio (FFR). OFR was computed offline in a central core-lab by analysts blinded to FFR. OFR was feasible in 98.7% of the lesions and showed excellent agreement with FFR (ICCa = 0.83, r = 0.83, slope = 0.80, intercept = 0.17, kappa = 0.84). The area under curve to predict an FFR ≤ 0.80 was ...

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    11. Comparison of Diagnostic Performance of Intracoronary Optical Coherence Tomography-based and Angiography-based Fractional Flow Reserve for Evaluation of Coronary Stenosis

      Comparison of Diagnostic Performance of Intracoronary Optical Coherence Tomography-based and Angiography-based Fractional Flow Reserve for Evaluation of Coronary Stenosis

      Aims: To evaluate the diagnostic performance of OCT-based optical flow ratio (OFR) in unselected patients and compare it with angiography-based quantitative flow ratio (QFR), using wire-based FFR as reference standard. Methods and results: All patients with OCT and FFR assessment prior to revascularization were analyzed. OFR and QFR were computed in blinded fashion and compared with FFR, all applying same cut-off value of ≤0.80 to define ischemia. Paired comparison between OFR and QFR was performed in 212 vessels from 181 patients. Average FFR was 0.82±0.10 and 40.1% vessels had FFR≤0.80. OFR showed significant ...

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    12. Challenging treatment of in-stent restenosis in a coronary bifurcation by implantation of a bioresorbable scaffold under optical coherence tomography guidance

      Challenging treatment of in-stent restenosis in a coronary bifurcation by implantation of a bioresorbable scaffold under optical coherence tomography guidance

      A 67-year-old male patient with stable angina, hypertension and hypercholesterolemia who underwent bare metal stent (BMS) implantation in the distal right coronary artery (RCA) (Azule 3 × 9 mm) and everolimus-eluting stent (EES) implantation in the first diagonal branch (D1) (Xience 2.25 × 18 mm) and in the proximal circumflex branch (LCx) (Xience 3 × 28 mm). One year subsequent to the precedure the patient was readmitted for relapse of the angina Canadian Cardiovascular Society scale II, exhibiting a positive exercise test. The coronary angiography showed a distal-edge in-stent restenosis (ISR) in the distal RCA, extending to the posterior descending artery (PDA ...

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    13. A formula to calculate the contrast volume required for optimal imaging quality in optical coherence tomography with non-occlusive technique

      A formula to calculate the contrast volume required for optimal imaging quality in optical coherence tomography with non-occlusive technique

      Background: Non-occlusive technique is universally accepted for acquisition of coronary optical coherence tomography (OCT), but the amount of contrast infused is still inconsistently calculated. Proposed herein, is an empirical formula for accurate contrast volume calculation. Methods: In an observational prospective study, contrast volume of consecutive patients undergoing OCT was either calculated with formula, or eyeballed based on manufacturer recommendations. The quality of pullback, defined as % of high quality cross-sections (CS) in the segment of interest (SOI), was analyzed by two independent operators and compared between groups, together with the amount of contrast per pullback. Results: Sixty patients (115 pullbacks, 4252 ...

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    14. Rational and Design of the European Randomized Optical Coherence Tomography Optimized Bifurcation Event Reduction Trial (OCTOBER)

      Rational and Design of the European Randomized Optical Coherence Tomography Optimized Bifurcation Event Reduction Trial (OCTOBER)

      Background Percutaneous coronary intervention (PCI) in complex bifurcation lesions is prone to suboptimal implantation results and is associated with increased risk of subsequent clinical events. Angiographic ambiguity is high during bifurcation stenting but it is unknown if procedural guidance by intravascular optical coherence tomography (OCT) improves clinical outcome. Methods and design OCTOBER is a randomized, investigator initiated, multi-center trial aimed to show superiority of OCT guided stent implantation compared to standard angiographic guided implantation in bifurcation lesions. The primary outcome measure is a two-year composite endpoint of cardiac death, target lesion myocardial infarction, and ischemia driven target lesion revascularization. The ...

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    15. Implantation of bioresorbable scaffolds under guidance of optical coherence tomography: feasibility and pilot clinical results of a systematic protocol

      Implantation of bioresorbable scaffolds under guidance of optical coherence tomography: feasibility and pilot clinical results of a systematic protocol

      Background: We hypothesise that a comprehensive optical coherence tomography (OCT)-guided implantation protocol for bioresorbable scaffolds (BRS) might improve expansion and apposition, thus translating into better clinical outcomes, particularly reducing thrombotic events. Methods: Patients considered suitable for BRS therapy in de novo coronary lesions underwent OCT. The predominant type of plaque was classified as lipidic, fibrous or calcific, undergoing tailored plaque preparation accordingly. After proper sizing, BRS was deployed and final OCT was acquired. Post-dilation was only performed if suboptimal deployment. Procedural and 12 months clinical follow-up are reported. Results: 29 patients (41 lesions) considered clinically and angiographically suitable for ...

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    16. Bas-relief in three dimensional optical coherence tomography: a novel sign after subintimal scaffolding in a chronic total occlusion

      Bas-relief in three dimensional optical coherence tomography: a novel sign after subintimal scaffolding in a chronic total occlusion

      A 69-years-old female with stable angina underwent percutaneous intervention of a chronic total occlusion (CTO) in the proximal right coronary artery (RCA) ( Panel A, Supplementary material online , Video S1 ). Septal collaterals supplied the distal vessel (Rentrop 3, CC1) ( Supplementary material online , Video S2 ).

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    17. Implantation of magnesium-bioresorbable scaffolds in a bifurcation under optical coherence tomography guidance

      Implantation of magnesium-bioresorbable scaffolds in a bifurcation under optical coherence tomography guidance

      A 68-years-old female with positive test of ischaemia in the anterior wall presented a severe coronary bifurcation lesion in the anterior descending (LAD) and first diagonal (D1) arteries, Medina 010 ( Panel A ; Supplementary material online, Video 1 ). OCT showed lipid-rich plaques in both vessels, extending proximally and distally to the take-off of the D1 (optical Medina 110). Balloons and scaffolds were sized

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    18. Optical coherence tomography imaging after successful percutaneous coronary intervention treatment of coronary perforation following bioabsorbable vascular scaffold implantation: Consecutive ping-pong and child-in-mother techniques

      Optical coherence tomography imaging after successful percutaneous coronary intervention treatment of coronary perforation following bioabsorbable vascular scaffold implantation: Consecutive ping-pong and child-in-mother techniques

      A 68-year-old male, former smoker, with dyslipidemia, and 7-year history of stable angina was admitted to our center due to symptom progression and positive treadmill test under optimal medical treatment with aspirin, beta-blockers, and highdose statins. Transradial coronary angiography evidenced a chronic total occlusion (CTO) of the proximal left anterior descending artery (LAD), severe stenosis of the proximal left circumflex artery (LCx), and a dominant right coronary artery with collateral flow to the mid and distal bed of the LAD (Rentrop 3, CC 2). Left ventricular (LV)-angiography evidenced LV normal size and function. LCx stenosis was successfully treated with ...

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    19. Time course of vascular response after an a priori strategy of bare metal stent implantation post-dilated with a paclitaxel-coated balloon: Implementation of a three dimensional analysis algorithm with optical coherence tomography

      Time course of vascular response after an a priori strategy of bare metal stent implantation post-dilated with a paclitaxel-coated balloon: Implementation of a three dimensional analysis algorithm with optical coherence tomography

      Background: An a priori combined therapy of a bare metal stent (BMS) post-dilated with a paclitaxel-coated balloon (PCB) was investigated with optical coherence tomography (OCT) at 2- and 6 months regarding vessel response. Previous studies have shown inconsistent results and the time course of vessel healing after such an interventional strategy is unknown. Methods: Thirty-three de novo lesions in 32 patients were electively treated. Six-month OCT analysis was available in 24 lesions. Two-month OCT f/u was obtained in 16 lesions. Sequential OCT at 2- and 6 months was available in 7 patients. A novel 3-dimensional picture of vessel segments ...

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    20. Impact of Side Branch Modeling on Computation of Endothelial Shear Stress in Coronary Artery Disease Coronary Tree Reconstruction by Fusion of 3D Angiography and OCT

      Impact of Side Branch Modeling on Computation of Endothelial Shear Stress in Coronary Artery Disease Coronary Tree Reconstruction by Fusion of 3D Angiography and OCT

      Background Computational fluid dynamics allow virtual evaluation of coronary physiology and shear stress (SS). Most studies hitherto assumed the vessel as a single conduit without accounting for the flow through side branches. Objectives This study sought to develop a new approach to reconstruct coronary geometry that also computes outgoing flow through side branches in hemodynamic and biomechanical calculations, using fusion of optical coherence tomography (OCT) and 3-dimensional (3D) angiography. Methods Twenty-one patients enrolled in the DOCTOR (Does Optical Coherence Tomography Optimize Revascularization) fusion study underwent OCT and 3D-angiography of the target vessel (9 left anterior descending, 2 left circumflex, 10 ...

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    21. Incomplete Stent Apposition Causes High Shear Flow Disturbances and Delay in Neointimal Coverage as a Function of Strut to Wall Detachment Distance: Implications for the Management of Incomplete Stent Apposition

      Incomplete Stent Apposition Causes High Shear Flow Disturbances and Delay in Neointimal Coverage as a Function of Strut to Wall Detachment Distance: Implications for the Management of Incomplete Stent Apposition

      BACKGROUND: Lack of re-endothelialization and neointimal coverage on stent struts has been put forward as the main underlying mechanism leading to late stent thrombosis. Incomplete stent apposition (ISA) has been observed frequently in patients with very late stent thrombosis after drug eluting stent implantation, suggesting a role of ISA in the pathogenesis of this adverse event. The aim of this study was to evaluate the impact of different degrees of ISA severity on abnormal shear rate and healing response with coverage, because of its potential implications for stent optimization in clinical practice. METHODS AND RESULTS: We characterized flow profile and ...

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    22. Tissue coverage and neointimal hyperplasia in overlap versus nonoverlap segments of drug-eluting stents 9 to 13 months after implantation: In vivo assessment with optical coherence tomography

      Tissue coverage and neointimal hyperplasia in overlap versus nonoverlap segments of drug-eluting stents 9 to 13 months after implantation: In vivo assessment with optical coherence tomography

      Background: Histologic experimental studies have reported incomplete neointimal healing in overlapping with respect to nonoverlapping segments in drug-eluting stents (DESs), but these observations have not been confirmed in human coronary arteries hitherto. On the contrary, angiographic and optical coherence tomography studies suggest that DES overlap elicits rather an exaggerated than an incomplete neointimal reaction.Methods: Optical coherence tomography studies from 2 randomized trials including sirolimus-eluting, biolimus-eluting, everolimus-eluting, and zotarolimus-eluting stents were analyzed at 9- to 13-month follow-up. Coverage in overlapping segments was compared versus the corresponding nonoverlapping segments of the same stents, using statistical pooled analysis.Results: Forty-two overlaps were ...

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    23. Plaque sealing and passivation with a mechanical self-expanding low outward force nitinol VShield device for the treatment of intravascular ultrasound and optical coherence tomography-derived thin cap fibroatheromas (TCFAS) in native coronary arteries

      Plaque sealing and passivation with a mechanical self-expanding low outward force nitinol VShield device for the treatment of intravascular ultrasound and optical coherence tomography-derived thin cap fibroatheromas (TCFAS) in native coronary arteries

      Aims: The aim of the pilot SECRITT trial was to evaluate the safety and feasibility of sealing the high risk IVUS and optical coherence tomography-derived thin cap fibroatheroma (TCFA), with a dedicated nitinol self-expanding vShield device. Methods and results: After screening with angiography, fractional flow reserve (FFR), intravascular ultrasound virtual histology (IVUS-VH) and optical coherence tomography (OCT), 23 patients met enrolment criteria (presence of non-obstructive VH-derived TCFA lesion with thin cap on OCT) and were randomised to vShield (n=13) versus medical therapy (n=10). In the shielded group, baseline percent diameter stenosis was 33.2±13.5%, FFR was ...

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    1-24 of 35 1 2 »
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    Quantitative multi-modality imaging analysis of a fully bioresorbable stent: a head-to-head comparison between QCA, IVUS, and OCT Tissue coverage of a hydrophilic polymer-coated zotarolimus-eluting stent vs. a fluoropolymer-coated everolimus-eluting stent at 13-month follow-up: an optical coherence tomography substudy from the RESOLUTE All Comers trial Delayed Coverage in Malapposed and Side-Branch Struts With Respect to Well-Apposed Struts in Drug-Eluting Stents: In Vivo Assessment With Optical Coherence Tomography Long-term tissue coverage of a biodegradable polylactide polymer–coated biolimus-eluting stent: Comparative sequential assessment with optical coherence tomography until complete resorption of the polymer Spatial Distribution and Temporal Evolution of Scattering Centers by Optical Coherence Tomography in the Poly(L-Lactide) Backbone of a Bioresorbable Vascular Scaffold Vascular Tissue Reaction to Acute Malapposition in Human Coronary Arteries: Sequential Assessment With Optical Coherence Tomography Response to Letter Regarding Article, “Delayed Coverage in Malapposed and Side-Branch Struts With Respect to Well-Apposed Struts in Drug-Eluting Stents: In Vivo Assessment With Optical Coherence Tomography” Differences in Neointimal Thickness Between the Adluminal and the Abluminal Sides of Malapposed and Side-Branch Struts in a Polylactide Bioresorbable Scaffold: Evidence In Vivo About the Abluminal Healing Process OCT in Coronary Bifurcations (Book Chapter) Plaque sealing and passivation with a mechanical self-expanding low outward force nitinol VShield device for the treatment of intravascular ultrasound and optical coherence tomography-derived thin cap fibroatheromas (TCFAS) in native coronary arteries Asynchronous feature regularization and cross-modal distillation for OCT based glaucoma diagnosis Developments and Clinical Applications of Noninvasive Optical Technologies for Skin Cancer Diagnosis