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

2021 ◽  
Vol 8 ◽  
Author(s):  
Jiayue Huang ◽  
Fan Yang ◽  
Juan Luis Gutiérrez-Chico ◽  
Tianxiao Xu ◽  
Jigang Wu ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Cardiac Cycle ◽  
Plaque Burden ◽  
Patient Specific ◽  
Plaque Morphology ◽  
Optical Coherence ◽  
Structural Stress ◽  
Biomechanical Assessment ◽  
Minimal Lumen Area

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 the changes in plaque structural stress (ΔPSS) on vessel wall over the cardiac cycle.Results: A total of 50 lesions from 41 vessels were analyzed. A significant ΔPSS gradient was observed across the plaque, being maximal at the proximal shoulder (45.7 [32.3, 78.6] kPa), intermediate at minimal lumen area (MLA) (39.0 [30.8, 69.1] kPa) and minimal at the distal shoulder (35.1 [28.2, 72.3] kPa; p = 0.046). The presence of lipidic plaques were observed in 82% of the diseased segments. Larger relative lumen deformation and ΔPSS were observed in diseased segments, compared with normal segments (percent diameter change: 8.2 ± 4.2% vs. 6.3 ± 2.3%, p = 0.04; ΔPSS: 59.3 ± 48.2 kPa vs. 27.5 ± 8.2 kPa, p < 0.001). ΔPSS was positively correlated with plaque burden (r = 0.37, p < 0.001) and negatively correlated with fibrous cap thickness (r = −0.25, p = 0.004).Conclusions: ΔPSS provides a feasible method for assessing plaque biomechanics in vivo from OCT images, consistent with previous biomechanical and clinical studies based on different methodologies. Larger ΔPSS at proximal shoulder and MLA indicates the critical sites for future biomechanical assessment.

Abstract WP1: High-Frequency Optical Coherence Tomography for Cerebrovascular Disease

Stroke ◽  
2020 ◽  
Vol 51 (Suppl_1) ◽  
Author(s):  
Ajit S Puri ◽  
Giovanni Ughi ◽  
Robert M King ◽  
Matthew Gounis
Keyword(s):  
Optical Coherence Tomography ◽  
Cerebrovascular Disease ◽  
High Frequency ◽  
Ex Vivo ◽  
Thrombus Formation ◽  
Image Resolution ◽  
Patient Specific ◽  
Optical Coherence

Introduction: Optical coherence tomography (OCT) has played an important role in the diagnosis and treatment guidance in coronary artery disease. However, existing OCT systems are not suitable for routine neurovascular applications due to the size and tortuosity of the arteries. Hypothesis: We seek to demonstrate a prototype high-frequency OCT (HF-OCT) capable of high-resolution imaging in simulated cerebrovascular anatomy. Methods: A low-profile HF-OCT system was constructed with an image resolution approaching 10μm. Using an in vitro, patient-specific model of the circle of Willis with circulating porcine blood, we characterized the delivery of the device and ability to image in a tortuous path. Also, human cadaver intracranial atherosclerosis plaques were imaged with HF-OCT and assessed by an expert imager. Finally, neurovascular devices were implanted in 8 pigs (Fig 1) and HF-OCT imaging was compared with gold-standard DSA and CT. Results: In the phantom, optimal blood clearance was achieved through an intermediate catheter (5 Fr Navien) with infusion of contrast at 5 ml/s in the internal carotid and basilar artery, and 3 ml/sec in the MCA. The in vivo study demonstrated that both malapposition of devices or thrombus formation along the device surface could be reliably diagnosed among 3 reviewers (Fleiss’s kappa of 0.87 and 0.9, respectively). This agreement was superior to DSA and CT. Imaging in tortuous swine brachial showed in all cases imaging free of artifacts, uniform illumination and ability to visualize vessel wall layers. Plaque types including ‘lipid pools’, fibrotic, and calcific tissue from cadaver specimens of ICAD could be adequately depicted by HF-OCT. Conclusion: In vitro, in vivo and ex vivo characterization of a novel HF-OCT device has shown it is capable of imaging in the tortuous intracranial vascular anatomy. This technology has to potential to aid in the diagnosis of cerebrovascular disease and guide optimal endovascular treatment.

scholarly journals Gender-based in-vivo comparison of culprit plaque characteristics and plaque microstructures using optical coherence tomography in acute coronary syndrome

2021 ◽  
Author(s):  
Krishna Prasad ◽  
Sreeniavs Reddy S ◽  
Jaspreet Kaur ◽  
Raghavendra Rao k ◽  
Suraj Kumar ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Acute Coronary Syndrome ◽  
Plaque Rupture ◽  
Plaque Morphology ◽  
Optical Coherence ◽  
Cholesterol Crystals ◽  
Coronary Syndrome ◽  
Significant Difference ◽  
Gender Based

Introduction: Women perform worse after acute coronary syndrome (ACS) than men. The reason for these differences is unclear. The aim was to ascertain gender differences in the culprit plaque characteristics in ACS. Methods:Patients with ACS undergoing percutaneous coronary intervention for the culprit vessel underwent optical coherence tomography (OCT) imaging. Culprit plaque was identified as lipid rich,fibrous, and calcific plaque. Mechanisms underlying ACS are classified as plaque rupture, erosion,or calcified nodule. A lipid rich plaque along with thin-cap fibroatheroma (TCFA) was a vulnerable plaque. Plaque microstructures including cholesterol crystals, macrophages, and microvessels were noted. Results: A total of 52 patients were enrolled (men=29 and women=23). Baseline demographic features were similar in both the groups except men largely were current smokers (P<0.001). Plaque morphology,men vs. women: lipid rich 88.0% vs. 90.5%; fibrous 4% vs 0%; calcific 8.0% vs. 9.5% (P = 0.64). Of the ACS mechanisms in males versus females; plaque rupture (76.9 % vs. 50 %), plaque erosion (15.4 % vs.40 %) and calcified nodule (7.7 % vs. 10 %) was noted (P = 0.139). Fibrous cap thickness was (50.19 ±11.17 vs. 49.00 ± 10.71 mm, P = 0.71) and thin-cap fibroatheroma (96.2% vs. 95.0%, P = 1.0) in men and women respectively. Likewise no significant difference in presence of macrophages (42.3 % vs. 30%, P = 0.76), microvessels (73.1% vs. 60 %, P = 0.52) and cholesterol crystals (92.3% vs. 80%, P = 0.38). Conclusion: No significant gender-based in-vivo differences could be discerned in ACS patients’ culprit plaques morphology, characteristics, and underlying mechanisms.

scholarly journals Plaque burden influences accurate classification of fibrous cap atheroma by in vivo optical coherence tomography in a porcine model of advanced coronary atherosclerosis

2018 ◽  
Vol 14 (10) ◽  
pp. 1129-1135 ◽  
Author(s):  
Christian B. Poulsen ◽  
Ryan M. Pedrigi ◽  
Nilesh Pareek ◽  
Ismail D. Kilic ◽  
Niels Ramsing Holm ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Coronary Atherosclerosis ◽  
Porcine Model ◽  
Plaque Burden ◽  
Optical Coherence ◽  
Fibrous Cap

Abstract 17859: Gender Difference in Underlying Plaque Morphology of the Culprit Lesion in Patients with Acute Myocardial Infarction: an in vivo Optical Coherence Tomography Study

Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Sining Hu ◽  
Haibo Jia ◽  
Tsunenari Soeda ◽  
Yoshiyasu Minami ◽  
Rocco Vergallo ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Acute Myocardial Infarction ◽  
Optical Coherence Tomography ◽  
Gender Difference ◽  
Plaque Rupture ◽  
Morphological Characteristics ◽  
Plaque Morphology ◽  
Optical Coherence ◽  
Culprit Lesion

Introduction: Autopsy studies in sudden cardiac death subjects showed female had higher incidence of erosion. However, the incidence of erosion in patients with acute myocardial infarction (AMI) has not been systematically studied. Hypothesis: This study was to study the gender difference in the prevalence and morphological characteristics of the culprit lesion in patients with AMI using intravascular optical coherence tomography (OCT). Methods: A total of 79 patients (65 male and 14 female) with AMI who underwent pre-intervention OCT imaging of the culprit lesion were included. Results: Baseline characteristics between the two groups were similar. In OCT findings, the incidence of thin-cap fibroatheroma (TCFA) was slightly lower and the fibrous cap thickness was slightly thicker in female than in male, but the differences were not significant. Defining underlying plaque morphology by genders, plaque erosion was more prevalent in female than in male, whereas plaque rupture was more frequent in male (Table). Conclusions: Erosion was the most frequent cause of AMI in female patients, whereas plaque rupture is the predominant underlying pathology of AMI in male patients.

Abstract 1988: Non-culprit Coronary Plaque Morphology in Patients WIth Acute Myocardial Infarction : An Optical Coherence Tomography Study in Vivo

Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Kenichi Fujii ◽  
Motomaru Masutani ◽  
Takahiro Okumura ◽  
Daizo Kawasaki ◽  
Takafumi Akagami ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Acute Myocardial Infarction ◽  
Optical Coherence Tomography ◽  
Plaque Rupture ◽  
Plaque Morphology ◽  
List Type ◽  
Optical Coherence ◽  
Fibrous Cap ◽  
Infarct Related Artery

Background: In vivo imaging studies in patients with acute myocardial infarction (AMI) have demonstrated important lesions at sites other than the culprit. However, it is not well assessed whether non-culprit plaques in the non-infarct-related artery have similar markers of plaque instability compared to non-culprit plaques in the infarct-related artery. The aim of this study is to investigate the morphologic features of the non-culprit plaque in infarct-related artery in comparison with that in non-infarct-related artery for AMI patients using optical coherence tomography (OCT) in vivo. Methods: OCT examinations were attempted prospectively using motorized pullback in all 3 major coronary arteries (at least 2/3 segment of each artery) for 34 AMI patients. In 34 patients, 118 focal plaques were identified (3.5 plaques per patient). Qualitative OCT analyses for each focal atherosclerotic plaque were performed using the previously validated criteria. TCFA was defined as a plaque with lipid content in a quadrant and the thinnest part of a fibrous cap measuring <65 μm. A plaque rupture contained a cavity that communicated with the lumen with an overlying residual fibrous cap fragment. A thrombus was defined as an irregular mass protruding into the lumen. Non-culprit plaques were divided into two groups according to their location: plaques in infarct-related artery (n=35) and plaques in non-infarct-related artery (n=83). Results: Non-culprit TCFA, plaque rupture, and thrombus were observed in 50 lesions of 26 patients (76%), 14 lesions of 11 patients (34%), and 27 lesions of 15 patients (44%), respectively. OCT analyses are shown in the Table . Conclusions: The morphology of non-culprit plaques in AMI patients is similar whether these plaques occur in the infarct-related artery or the non-infarct-related artery. This suggests that plaque destabilization is a systemic phenomenon rather than a local, artery-specific process. OCT Analyses

scholarly journals 3D reconstruction of coronary artery bifurcations from coronary angiography and optical coherence tomography: feasibility, validation, and reproducibility

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Wei Wu ◽  
Saurabhi Samant ◽  
Gijs de Zwart ◽  
Shijia Zhao ◽  
Behram Khan ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Coronary Artery ◽  
3D Reconstruction ◽  
Three Dimensional ◽  
Plaque Burden ◽  
Patient Specific ◽  
Optical Coherence ◽  
Micro Computed Tomography ◽  
Processing Times ◽  
Mean Differences

Abstract The three-dimensional (3D) representation of the bifurcation anatomy and disease burden is essential for better understanding of the anatomical complexity of bifurcation disease and planning of stenting strategies. We propose a novel methodology for 3D reconstruction of coronary artery bifurcations based on the integration of angiography, which provides the backbone of the bifurcation, with optical coherence tomography (OCT), which provides the vessel shape. Our methodology introduces several technical novelties to tackle the OCT frame misalignment, correct positioning of the OCT frames at the carina, lumen surface reconstruction, and merging of bifurcation lumens. The accuracy and reproducibility of the methodology were tested in n = 5 patient-specific silicone bifurcations compared to contrast-enhanced micro-computed tomography (µCT), which was used as reference. The feasibility and time-efficiency of the method were explored in n = 7 diseased patient bifurcations of varying anatomical complexity. The OCT-based reconstructed bifurcation models were found to have remarkably high agreement compared to the µCT reference models, yielding r2 values between 0.91 and 0.98 for the normalized lumen areas, and mean differences of 0.005 for lumen shape and 0.004 degrees for bifurcation angles. Likewise, the reproducibility of our methodology was remarkably high. Our methodology successfully reconstructed all the patient bifurcations yielding favorable processing times (average lumen reconstruction time < 60 min). Overall, our method is an easily applicable, time-efficient, and user-friendly tool that allows accurate and reproducible 3D reconstruction of coronary bifurcations. Our technique can be used in the clinical setting to provide information about the bifurcation anatomy and plaque burden, thereby enabling planning, education, and decision making on bifurcation stenting.

scholarly journals Focal Geometry and Characteristics of Erosion-Prone Coronary Plaques in vivo Angiography and Optical Coherence Tomography Study

2021 ◽  
Vol 8 ◽  
Author(s):  
Muhua Cao ◽  
Tianyu Wu ◽  
Jiawei Zhao ◽  
Zhuo Du ◽  
Zhuozhong Wang ◽  
...  
Keyword(s):  
Risk Factors ◽  
Optical Coherence Tomography ◽  
Thrombus Formation ◽  
Multivariable Analysis ◽  
Coronary Risk Factors ◽  
Coronary Ostium ◽  
Optical Coherence ◽  
Luminal Narrowing ◽  
Minimal Lumen Area

Objective: This study compared focal geometry and characteristics of culprit plaque erosion (PE) vs. non-culprit plaques in ST-segment elevated myocardial infarction (STEMI) patients in whom optical coherence tomography (OCT) identified PE as the cause of the acute event.Background: Culprit PE is a distinct clinical entity with specific coronary risk factors and its own tailored management strategy. However, not all plaques develop erosion resulting in occlusive thrombus formation.Methods: Between January 2017 and July 2019, there were 484 STEMI patients in whom OCT at the time of primary percutaneous intervention identified culprit lesion PE to be the cause of the event; 484 culprit PE were compared to 1,132 non-culprit plaques within 1,196 imaged vessels.Results: Culprit PE were highly populated at “hot spots” within the proximal 40 mm in the left anterior descending artery (LAD) and tended to cluster proximal to a nearby bifurcation mainly in the LAD. Minimal lumen area (MLA) &lt;2.51 mm2 and AS (area stenosis) &gt;64.02% discriminated culprit PE from non-culprit plaques. In the multivariable analysis, focal geometry (LAD location, distance from coronary ostium &lt;40 mm, and location proximal to a nearby bifurcation), luminal narrowing (MLA &lt;2.51 mm2, AS &gt; 64.02%), and TCFA phenotype were independent predictors of culprit PE overall. Cholesterol crystals were predictive of culprit PE with underlying LRP morphology while the absence of calcification and microchannels were risk factors for culprit PE with an underlying non-LRP. Similarities and differences in predictors of culprit PE were found between males and females; distance from coronary ostium &lt;40 mm, MLA &lt;2.51 mm2, TCFA, and less spotty calcium were risk factors of culprit PE in males, but not in females while smaller RVD was associated with culprit PE only in females.Conclusions: Irrespective of underlying lesion substrates and patient risk factors, there are lesion-specific and OCT-identifiable predictors of developing culprit PE in erosion-prone vulnerable patients.

Abstract 383: Patient-Specific Coronary Models Combining Intravascular Ultrasound and Optical Coherence Tomography Lead to More Accurate Plaque Cap Thickness and Stress/Strain Quantifications

2017 ◽  
Vol 37 (suppl_1) ◽  
Author(s):  
Xiaoya Guo ◽  
David Monoly ◽  
Chun Yang ◽  
Habib Samady ◽  
Jie Zheng ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Intravascular Ultrasound ◽  
Coronary Plaque ◽  
Patient Specific ◽  
Data Sets ◽  
Optical Coherence ◽  
Stress Strain ◽  
Data Set ◽  
The Impact

Accurate cap thickness and stress/strain quantifications are of fundamental importance for vulnerable plaque research. An innovative modeling approach combining intravascular ultrasound (IVUS) and optical coherence tomography (OCT) is introduced for more accurate patient-specific coronary morphology and stress/strain calculations. In vivo IVUS and OCT coronary plaque data were acquired from two patients with informed consent obtained. IVUS and OCT images were segmented, co-registered, and merged to form the IVUS+OCT data set, with OCT providing accurate cap thickness. Biplane angiography provided 3D vessel curvature. Due to IVUS resolution (150 μm), original virtual histology (VH) IVUS data often had lipid core exposed to lumen since it sets cap thickness as zero when cap thickness <150 μm. VH-IVUS data were processed with minimum cap thickness set as 50 and 180 μm to generate IVUS50 and IVUS180 data sets for modeling use. 3D fluid-structure interaction models based on IVUS+OCT, IVUS50 and IVUS180 data sets were constructed to investigate the impact of OCT cap thickness improvement on stress/strain calculations. Figure 1 is a brief summary of results from 27 slices with cap covering lipid cores from 2 patients. Mean cap thickness (unit: mm) from Patient 1 was 0.353 (OCT), 0.201 (IVUS50), and 0.329 (IVUS180), respectively. Patient 2 mean cap thickness was 0.320 (OCT), 0.224 (IVUS50), and 0.285 (IVUS180). IVUS50 underestimated cap thickness (27 slices) by 34.5%, compared to OCT cap values. IVUS50 overestimated mean cap stress (27 slices) by 45.8%, compared to OCT cap stress (96.4 vs. 66.1 kPa). IVUS50 maximum cap stress was 59.2% higher than that from IVUS+OCT model (564.2 vs. 354.5 kPa). Differences between IVUS and IVUS+OCT models for mean cap strain and flow shear stress were modest (cap strain: <12%; FSS <2%). Conclusion: IVUS+OCT data and models could provide more accurate cap thickness and stress/strain calculations which will serve as basis for plaque research.

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