Coronary Artery Plaque Composition Research Articles

Insulin resistance is associated with high-risk coronary artery plaque composition in asymptomatic men between 65 and 75 years and no diabetes: A DANCAVAS cross-sectional sub-study

Background and aimsInsulin resistance (IR) and pre-diabetes are associated with an increased risk of cardiovascular disease (CVD). We aimed to investigate vulnerable plaque composition in relation to IR and pre-diabetes in asymptomatic non-diabetic men. MethodsAll participants underwent a contrast-enhanced coronary computed tomography angiography (CCTA) to evaluate coronary artery plaque burden and plaque composition (necrotic core, dense calcium, fibrotic and fibrous-fatty volume). Homeostasis model assessment of IR (HOMA-IR) was used, and participants were stratified into tertiles. Participants underwent a standard oral glucose tolerance test (OGTT) and were categorized into 2 groups (normal glucose tolerance (NGT) or pre-diabetes). A multivariable linear regression model was used to evaluate the association between vulnerable plaque composition and IR or glycemic group. ResultsFour-hundred-and-fifty non-diabetic men without known CAD were included. The mean age was 70 ± 3 years. Participants in the higher HOMA-IR tertile (H-IR) had higher median necrotic plaque volume compared to the lower HOMA-IR tertile (L-IR) (18.2 vs. 11.0 mm3, p = 0.02). H-IR tertile (β 0.37 [95% CI 0.10–0.65], p = 0.008), pack-years (β 0.07 [95% CI 0.007–0.14], p = 0.03) and total atheroma volume (TAV) (β 0.47 [95% CI 0.36–0.57], p < 0.001) remained associated with necrotic plaque volume in the multivariable linear regression model. ConclusionsIR was associated with necrotic plaque volume in asymptomatic men without diabetes. Thus, even in asymptomatic men without diabetes, IR seems to have an incremental effect on necrotic plaque volume and vulnerable plaque composition.

Correlation between coronary artery plaque composition ratio and plaque stability evaluated by 124-layer CT.

Correlation between coronary artery plaque composition ratio and plaque stability evaluated by 124-layer CT.

Coronary Artery Plaque Composition and Severity Relate to the Inflammasome in People With Treated Human Immunodeficiency Virus.

Inflammasome activation is increased in people with human immunodeficiency virus (PWH), but its relationship with coronary plaque is poorly understood in this setting. In a large human immunodeficiency virus cardiovascular prevention cohort, relationships between caspase-1, interleukin (IL)-1β, and IL-18 and coronary plaque indices were assessed by multivariate logistic regression. Higher IL-18 and IL-1β were associated with Leaman score, an integrative measure of plaque burden and composition. As Leaman score >5 is associated with cardiovascular events in the general population, future work is needed to determine how the inflammasome relates to events and whether strategies to reduce its activation affect events or plaque progression among PWH.

Relationship Between Sclerostin Levels and Coronary Artery Calcification and Plaque Composition.

The primary function of sclerostin is the regulation of bone metabolism. Research investigating the cardiovascular effects of sclerostin had conflicting results. We aimed to study serum sclerostin levels in coronary artery plaque types. Coronary calcium scores of 175 patients were evaluated. Patients with normal coronary arteries and calcium score of greater than zero constituted control (n = 47) and study groups (n = 83), respectively. Patients' plaques were further categorized as non-calcified plaque, calcified plaque, or mixed plaque (n = 45, n = 40, and n = 43, respectively). The study group had increased serum sclerostin levels than that of controls. Moreover, sclerostin levels were significantly higher in patients with calcified or mixed plaques compared to those without plaque or non-calcified plaque (median 248.5, 60.7-790.4) pg/mL and 1085.8 (185.8-3902.2) pg/mL versus 68.7 (34.0-141.3) pg/mL, and 67.7 (48.6-94.9) pg/mL, P < 0.001, respectively). Sclerostin showed a high correlation with coronary calcium scores (r = 0.95, P < 0.001). Serum sclerostin concentration of 106.27 pg/mL had 97.5% sensitivity and 67.4% specificity for the prediction of calcific plaque, whereas the level of 308.55 pg/mL had 95.3% sensitivity and 90.9% specificity for the prediction of mixed plaque. Coronary calcium scores, serum sclerostin, and C-reactive protein levels were significant predictors of 1-year major adverse cardiac events. Increased serum sclerostin level is a marker of coronary atherosclerosis burden and has a value for the prediction of 1-year major adverse cardiac events.

Abstract 11941: Accuracy of OCT Core Labs in Determining Coronary Artery Plaque Composition

Introduction: Intravascular optical coherence tomography (OCT) provides a high-resolution representation of coronary atherosclerosis. However, the accuracy of OCT image interpretation is unknown. We present a blinded study of histologically identified OCT human plaque composition by leading international OCT core labs. Hypothesis: Human readers are unable to accurately identify all plaque compositions. Methods: Seven recognized OCT core labs (Japan, Netherlands, Switzerland, USA) participated. Each laboratory was provided 51 OCT image clips recorded from ex vivo human coronary arteries within 24 hours of death and had regions of interest processed for H&amp;E stain. Nine plaque components were identified and are listed in Results. Each OCT core lab was asked to blindly read OCT images and complete a questionnaire indicating one of nine possible plaque types. Kappa coefficient ( k ) was used ( k &lt; 0.5 poor agreement, k &gt; 0.5 high agreement) to measure intra-reader agreement; the median k is reported for each plaque component. Results: High agreement was demonstrated in identifying stable plaque including fibrous (0.93), calcium (0.83), layered plaque (1.0), and ThCFA (0.63), in contrast to unstable plaque including calcified nodule (0.50), lipid pool (0.35), macrophages/foam cells (0.35), TCFA (0.39), and necrotic core (0.22). When categories were restricted to Fibrous, Calcium, and Lipids, with Lipids expanded to include lipid pool, TCFA, and necrotic core, similar to an OCT core lab definition, k for Lipids increased to 0.61. Conclusions: Results suggest that participating OCT core labs can accurately identify combined lipid categories (lipid pool, TCFA, and necrotic core), fibrous tissue and calcium. However, accuracy is reduced when reading more sophisticated unstable plaque components. Study results emphasize the need for the development of OCT plaque composition analysis with artificial intelligence.

Comparative Study between Diabetic and non- Diabetic Patients Regarding Prevalence of Coronary Artery Disease and Plaque Composition by Multi-detector CT Coronary Angiography

Abstract Diabetes is known to be a major cardiovascular risk factor associated with significantly increased morbidity and mortality and particularly increased risk of major cardiac events especially myocardial infarction as a manifestation of highly incident coronary artery disease (CAD).This can lead to decreased life expectation and life quality. Major cause for myocardial infarction is plaque rupture. Prevalence of obstructive and non-obstructive plaques is increased in diabetic patients. Background and Objectives The prevalence of coronary heart disease in diabetic patients compared to non- diabetics and evaluating the composition of the plaque in diseased individuals in both groups by usage of multislice computed tomography (MSCT) angiography . Subjects and Methods A total of 80 consecutive MSCT angiography examinations were performed between August 2017 and June 2018. Of these, the patients were evaluated for the presence and type of atherosclerotic plaque and severity of luminal narrowing. Results Eighty (40 in the diabetic group and 40 in the non-diabetic group) patients underwent MSCT angiography with DM prevalence of 0.212 (95% Cl for AOR 0.056 -1.896). Among them, 20 patients (50 %) in the diabetic group and 14 patients (35 %) in the non-diabetic group had +ve coronary heart disease, 33.3 % had significant and moderately significant coronary narrowing on diabetic group and 31.3 % in non-diabetic group on MSCT angiography. Diabetic patients had more soft plaque compared with non-diabetic patients. Conclusion DM is not an independent factor for the disease occurrence in coronary artery disease but is a dependent factor in the association of other risk factors such as smoking ,hypertension and dyslipidemia.

A novel density-volume calcium score by non-contrast CT predicts coronary plaque burden on coronary CT angiography: Results from the MACS (Multicenter AIDS cohort study)

BackgroundThe purpose of this study is to determine if a new score calculated with coronary artery calcium (CAC) density and volume is associated with total coronary artery plaque burden and composition on coronary CT angiography (CCTA) compared to the Agatston score (AS). MethodsWe identified 347 men enrolled in the Multicenter AIDS cohort study who underwent contrast and non-contrast CCTs, and had CAC>0. CAC densities (mean Hounsfield Units [HU]) per plaque) and volumes on non-contrast CCT were measured. A Density-Volume Calcium score was calculated by multiplying the plaque volume by a factor based on the mean HU of the plaque (4, 3, 2 and 1 for 130–199, 200–299, 300–399, and ≥400HU). Total Density-Volume Calcium score was determined by the sum of these individual scores. The semi-quantitative partially calcified and total plaque scores (PCPS and TPS) on CCTA were calculated. The associations between Density-Volume Calcium score, PCPS and TPS were examined. ResultsOverall, 2879 CAC plaques were assessed. Multivariable linear regression models demonstrated a stronger association between the log Density-Volume Calcium score and both the PCPS (β 0.99, 95%CI 0.80–1.19) and TPS (β 2.15, 95%CI 1.88–2.42) compared to the log of AS (PCPS: β 0.77, 95%CI 0.61–0.94; TPS: β 1.70, 95%CI 1.48–1.94). Similar results were observed for numbers of PC or TP segments. ConclusionThe new CAC score weighted towards lower density demonstrated improved correlation with semi-quantitative PC and TP burden on CCTA compared to the traditional AS, which suggests it has utility as an alternative measure of atherosclerotic burden.

Sex differences in coronary artery plaque composition detected by coronary computed tomography: quantitative and qualitative analysis.

BackgroundSex differences in the calculation of coronary heart disease risk have been analysed extensively. However, data on coronary plaque morphology diverge. We analysed plaque characteristics in patients with suspected coronary artery disease (CAD) and defined prognostic factors using coronary computed tomography angiography (CCTA).MethodsA total of 6,050 consecutive patients underwent CCTA and were enrolled in the registry. Patients with known CAD were excluded. The patients were propensity score matched (1:1 male:female) for age and known coronary risk factors. Coronary arteries were evaluated for stenosis, plaque types (non-calcified, mixed and calcified) and high-risk plaque features (napkin-ring sign, low-attenuation plaque, spotty calcifications, positive remodelling). Clinical follow-up was performed.ResultsA total of 1,050 patients (525 female, 525 male) in matched cohorts were selected for analysis. CCTA showed significantly higher calcium scores for males (mean 180.5 vs 67.8 AU, p < 0.0001) and a higher rate of CAD (66.0% vs 34.1%, p < 0.0001). In a total of 16,800 segments, males had significantly more plaques (861 vs 752, p < 0.0001) with a significantly larger proportion of calcified plaques, while females had more mixed and non-calcified plaques (33.5% vs 24.4%, p = 0.006 and 24.1% vs 13.6%, p = 0.22, respectively). After a mean follow-up of 5.6 years, major adverse cardiac event (MACE) rate was 5.3% in male and 1.9% in female patients (p < 0.05). The relative odds ratio for high-risk plaque features to predict MACE was higher in females.ConclusionBased on a higher relative risk for women with high-risk plaque features, the findings of our study support the increased importance of a differentiated qualitative plaque analysis to improve the risk stratification for both sexes.

300.06 Gender Disparities Within the Lipid Rich Plaque (LRP) Study: Does the LCBI Differ Between Women and Men?

Differences in the development of coronary atherosclerosis between women and men have repeatedly been reported. Unfortunately, little is known about the impact of gender on coronary artery plaque composition. This is of particular importance since the actual in vivo plaque characteristics, i.e.,

Abstract 17172: Ethnic Differences in Prevalence of Coronary Artery Calcification and Plaque Composition Among Whites and African Americans

Introduction: Racial differences in the prevalence of coronary artery calcification (CAC) are well documented. African Americans (AA) tend to have a lower prevalence of CAC despite greater coronary risk factors and according to some reports higher cardiovascular disease (CVD) morbidity and mortality Hypothesis: We hypothesize despite a lower prevalence of CAC; AA would have similar or higher burden of non-calcified plaque (NCP). Methods: We retrospectively evaluated data from 4280 (3886 whites and 482 AA) consecutive patients, who underwent non-contrast and contrast cardiac computed tomography at our center. We used the 17-segment American Heart Association classification for assessment of coronary arteries. We quantified the amount of plaque in each segment as mild (score of 1), moderate (score of 2), or severe (score of 3) using a previously described method. We calculated total plaque score (TPS) by summation of the amount of plaque of each coronary segment. The non-calcified plaque score (NCPS) and mixed plaque score (MPS) were similarly calculated by summing the plaque scores in each segment separately. The segment involvement score (SIS), ranging from 0 to 17, was calculated as the total number of segments with any plaque; the segment stenosis score (SSS), was obtained by grading the stenosis severity of each segment with plaque, as was previously described in literature. Results: Prevalence of CAC&gt;0 was 77% in whites versus 61% in AA (median Interquartile range]:190[13-780] versus 38[0-275];P&lt;0.001). After adjustment for age, diabetes, BMI, family history of CAD, chest pain, hyperlipidemia, HTN and smoking, there was no significant difference in NCPS (β(Se) = 0.1 (0.4), P=0.731) and MPS (β(Se) = -0.4 (0.8), p=0.590) in AA compared with whites. TPS (β(Se) = -1.6 (0.4), P&lt;0.001), SSS (B(Se)=-1.5(0.5), p&lt;0.001 and Segment involvement score (B(Se)= 0.9 (0.2), P&lt;0.001) were significantly lower in AA compared with whites. Conclusion: Despite the significantly lower prevalence of CAC in AA, the burden of NCP and mixed plaque were similar in AA compared with whites. Further studies would be needed to elucidate whether the higher burden of NCP burden despite a lower prevalence of CAC is responsible for higher CVD mortality in AA.

Prognostic value of coronary computed tomographic angiography findings in asymptomatic individuals: a 6-year follow-up from the prospective multicentre international CONFIRM study.

The long-term prognostic benefit of coronary computed tomographic angiography (CCTA) findings of coronary artery disease (CAD) in asymptomatic populations is unknown. From the prospective multicentre international CONFIRM long-term study, we evaluated asymptomatic subjects without known CAD who underwent both coronary artery calcium scoring (CACS) and CCTA (n = 1226). Coronary computed tomographic angiography findings included the severity of coronary artery stenosis, plaque composition, and coronary segment location. Using the C-statistic and likelihood ratio tests, we evaluated the incremental prognostic utility of CCTA findings over a base model that included a panel of traditional risk factors (RFs) as well as CACS to predict long-term all-cause mortality. During a mean follow-up of 5.9 ± 1.2 years, 78 deaths occurred. Compared with the traditional RF alone (C-statistic 0.64), CCTA findings including coronary stenosis severity, plaque composition, and coronary segment location demonstrated improved incremental prognostic utility beyond traditional RF alone (C-statistics range 0.71-0.73, all P < 0.05; incremental χ2 range 20.7-25.5, all P < 0.001). However, no added prognostic benefit was offered by CCTA findings when added to a base model containing both traditional RF and CACS (C-statistics P > 0.05, for all). Coronary computed tomographic angiography improved prognostication of 6-year all-cause mortality beyond a set of conventional RF alone, although, no further incremental value was offered by CCTA when CCTA findings were added to a model incorporating RF and CACS.

A novel workflow combining plaque imaging, plaque and plasma proteomics identifies biomarkers of human coronary atherosclerotic plaque disruption

BackgroundAtherosclerotic plaque rupture is the culprit event which underpins most acute vascular syndromes such as acute myocardial infarction. Novel biomarkers of plaque rupture could improve biological understanding and clinical management of patients presenting with possible acute vascular syndromes but such biomarker(s) remain elusive. Investigation of biomarkers in the context of de novo plaque rupture in humans is confounded by the inability to attribute the plaque rupture as the source of biomarker release, as plaque ruptures are typically associated with prompt down-stream events of myocardial necrosis and systemic inflammation.MethodsWe developed a novel approach to identify potential biomarkers of plaque rupture by integrating plaque imaging, using optical coherence tomography, with both plaque and plasma proteomic analysis in a human model of angioplasty-induced plaque disruption.ResultsWe compared two pairs of coronary plaque debris, captured by a FilterWire Device, and their corresponding control samples and found matrix metalloproteinase 9 (MMP9) to be significantly enriched in plaque. Plaque contents, as defined by optical coherence tomography, affect the systemic changes of MMP9. Disruption of lipid-rich plaque led to prompt elevation of plasma MMP9, whereas disruption of non-lipid-rich plaque resulted in delayed elevation of plasma MMP9. Systemic MMP9 elevation is independent of the associated myocardial necrosis and systemic inflammation (measured by Troponin I and C-reactive protein, respectively). This information guided the selection of a subset of subjects of for further label free proteomics analysis by liquid chromatography tandem mass spectrometry (LC–MS/MS). We discovered five novel, plaque-enriched proteins (lipopolysaccharide binding protein, Annexin A5, eukaryotic translocation initiation factor, syntaxin 11, cytochrome B5 reductase 3) to be significantly elevated in systemic circulation at 5 min after plaque disruption.ConclusionThis novel approach for biomarker discovery in human coronary artery plaque disruption can identify new biomarkers related to human coronary artery plaque composition and disruption.

Association between adiposity and systemic atherosclerosis: a protocol of a cross-sectional autopsy study

IntroductionAdiposity has been associated with atherosclerosis in clinical studies. However, few autopsy studies have investigated this association, and they had only examined the coronary artery disease. Moreover, most studies had...

SU‐C‐206‐02: Estimating Coronary Artery Plaque Composition with a Combined Dual‐Energy and Single‐Energy QCT Optimization Model

Purpose:A study was performed to evaluate the accuracy of a combined dual‐energy/single‐energy QCT optimization model for estimating the volume fractions of fat, cholesterol, protein, fibrous tissue, and calcium in coronary artery plaque.Methods:This model uses 80kVp‐140kVp CT# data to distinguish calcium, and Gaussian component analysis based on the 140kVp CT#'s of the pure materials to distinguish the other constituents. An experimental study was performed with a thorax section phantom (CIRS, Inc.) containing various mixtures of 0.8–3.2mm thick plastic slabs simulating plaque components. The Z(eff), ρ(g/cc) properties of the plaque components and plaque‐simulating plastics are: [fat(5.82,0.92), LDPE(5.44, 0.92)], [cholesterol(5.65,1.067), polystyrene(5.62,1.05)], protein(6.73,1.38), Delrin (7.07,1.42)], fibrous(7.51, 1.05), nylon(6.21, 1.14]). Two water‐equivalent plastics containing CaCO3 (13% and 22% CaCO3) were also used. Scans of 6.4‐mm‐thick slabs of each plastic alone within the phantom were acquired to determine the CT#'s of the pure materials. All scans were repeated 3 times under each condition and reconstructed with standard (STD) and BONE kernels on a GE CT750HD CT scanner using a 10‐cm reconstruction FOV.Results:The minimum RMS errors for the various plaque‐simulating slab mixtures were 2.2% (BONE kernel) and 4.2% (STD kernel) for a 1.6mm 13% CaCO3, 3.2mm polystyrene, 3.2mm delrin, 3.2mm nylon slab mixture (total=11.2mm). Maximum RMS errors were 7.5% (BONE) and 13.7% (STD) for a mixture containing 1.6mm slabs of 13% CaCO3, LDPE, delrin, and nylon (total=6.4mm).Conclusion:The accuracy of the method decreased as the thicknesses of the slabs decreased, due to volume averaging. Accuracy was better for the BONE kernel that has higher spatial resolution. Even for this kernel, the errors are substantial for a mixture that is about the size of the coronary artery lumen (2–6mm). Higher spatial resolution and more quantitative reconstruction methods are needed to improve the accuracy of the method.NIH RO1 HL106545

Plaque Rupture Relationship to Plaque Composition in Coronary Arteries. A 320-Slice CT Angiographic Analysis

Abstract Background Coronary thrombosis leading to myocardial ischemia is now recognized as a diverse process arising from plaque rupture, erosion, or calcified nodules. These vulnerable plaques may not always cause significant stenosis of the artery, and therefore be missed on an invasive catheter angiogram (ICA). The advent of multidetector computed tomography (MDCT) imaging of the walls of the coronary artery has opened a unique window to these vulnerable plaques. Differentiation of calcified plaques from soft plaques presents no challenge on CT. Further characterization of the plaque into a ruptured plaque is possible by demonstration of discontinuity of the plaque surface and contrast pooling within the plaque substance. Purpose To study the relation between coronary artery plaque rupture and plaque composition. Materials and methods 500 patients referred for coronary CT angiogram between 2008 and 2013, who had plaque thicknesses of 2mm or more, were included in the study. The plaques were divided into totally calcified, mixed, and soft categories. The totally calcified plaques were excluded from the study as none of these showed signs of plaque rupture. A total number of 2667 mixed and soft plaques were included in the study. Results 52% of the total plaques were ruptured and 48% not ruptured. Of the ruptured plaques, 96.9% were mixed type and only 3.7% were soft. And of the non-ruptured plaques, 96.3% were soft and only 3.1% mixed ( p Conclusion This study reveals that plaque rupture is significantly associated with mixed plaques containing soft and calcific areas rather than purely soft plaques.

Intravascular ultrasound study of coronary artery remodeling and plaque composition in patients with coronary atherosclerotic heart disease

Objective To demonstrate the relationship between plaque composition and coronary artery remodeling in the same patient′s blood vessel. Methods A total of 48 coronary artery plaque were included in this study. Qualitative assessment and quantitative measurements of the lesion were performed in target lesions. The lesions were classified into soft plaque, fibrous plaque, calcified plaque and mixed plaque according to different degree of reflection of ultrasound signal. The remodeling index (RI) was defined as the ratio of external elastic membrane cross sectional area of lesion segment to the mean reference external elastic membrane cross sectional area. Results In comparison to hard plaque group, RI of soft plaque group was significantly larger in the same patient (1.08±0.15 vs 1.00±0.13, P=0.000). Soft plaque group presented with more positive remodeling than hard plaque group, but with P value more than 0.05 (83.3% vs 58.3%, P=0.057). The plaque area, lumen area and plaque burden were not different between two group (P>0.05). Conclusions The blood vessel was compensatively dilated in soft plaque segments and RI was significantly larger than in hard plaque segments. Coronary atherosclerotic vessel presented positive remodeling in the acute stage of inflammation. Key words: Endosonography; Coronary artery heart disease; Remodeling; Plaque; Atherosclerotic

The effect of coronary artery plaque composition, morphology and burden on Absorb bioresorbable vascular scaffold expansion and eccentricity — A detailed analysis with optical coherence tomography

AimsSuboptimal stent expansion correlates with adverse cardiac events. There is limited information regarding Absorb bioresorbable vascular scaffold (BVS) expansion characteristics. Optical coherence tomography (OCT) allows for high-resolution assessment of plaque morphology, composition and assessment of BVS expansion. This study evaluates coronary plaque composition, morphology and burden and their effect on Absorb BVS expansion using OCT. Methods and resultsTwo thousand three hundred and thirty four frames totalling 462.6mm of BVS from twenty OCT-guided BVS implantations were examined. 200μm longitudinal cross-sections of each BVS were analysed for lumen contours and plaque characteristics. The relationship between each plaque characteristic and scaffold expansion index (SEI) or scaffold eccentricity index (SEC) was analysed by repeated measures ANOVA.Forty-four fibrous and 265 calcific plaques were identified. Lower SEI was significantly (p<0.001) associated with greater calcific plaque (CP) area (mean SEI 78.9% vs. 80.0%), thickness (78.5% vs. 80.4%) and lower CP depth (78.3% vs. 80.2%). Lower SEC was significantly (p<0.001) associated with greater fibrous plaque (FP) area (0.84 vs. 0.85), thickness (0.83 vs. 0.86), arc angle (0.84 vs. 0.85), greater CP area (0.83 vs. 0.86), CP thickness (0.83 vs. 0.86), CP angle (0.84 vs. 0.85) and lower CP depth (0.84 vs. 0.85). Greater FP area was associated with greater SEI (81.0% vs. 80.0%, p<0.001), even after adjustment for target vessel size. Greater FP angle (80.7% vs 78.3%, p<0.001) and quadrants occupied were also associated (80.0% vs 78.5%, p<0.002) with greater SEI. ConclusionBVS expansion and eccentricity are significantly impacted by plaque composition, morphology and burden.

An assessment of intra-patient variability on observed relationships between wall shear stress and plaque progression in coronary arteries.

BackgroundWall shear stress (WSS) has been associated with sites of plaque localization and with changes in plaque composition in human coronary arteries. Different values have been suggested for categorizing WSS as low, physiologic or high; however, uncertainties in flow rates, both across subjects and within a given individual, can affect the classification of WSS and thus influence the observed relationships between local hemodynamics and plaque changes over time. This study examines the effects of uncertainties in flow rate boundary conditions upon WSS values and investigates the influence of this variability on the observed associations of WSS with changes in VH-IVUS derived plaque components.MethodsThree patients with coronary artery disease underwent baseline and 12 month follow-up angiography and virtual histology-intravascular ultrasound (VH-IVUS) measurements. Coronary artery models were reconstructed from the data and models with and without side-branches were created. Patient-specific Doppler ultrasound (DUS) data were employed as inflow boundary conditions and computational fluid dynamics was used to calculate the WSS in each model. Further, the influence of representative coronary artery flow waveforms upon WSS values was investigated and the concept of treating WSS using relative, rather than actual, values was explored.ResultsModels that included side-branch outflows and subject-specific DUS velocities were considered to be the reference cases. Hemodynamic differences were caused by the exclusion of side-branches and by imposing alternative velocity waveforms. One patient with fewer side-branches and a scaled generic waveform had little deviation from the reference case, while another patient with several side-branches excluded showed much larger departures from the reference situation. Differences between models and the respective reference cases were reduced when data were analyzed using relative, rather than actual, WSS.ConclusionsWhen considering individual subjects, large variations in patient-specific flow rates and exclusion of multiple side-branches in computational models can cause significant differences in observed associations between plaque evolution and ranges of computed WSS. These differences may contribute to the large variability typically found among subjects in pooled populations. Relative WSS may be more useful than actual WSS as a correlative variable when there is a large degree of uncertainty in flow rate data.

Plasma lipidomic analysis predicts non-calcified coronary artery plaque in asymptomatic patients at intermediate risk of coronary artery disease

The optimal management of asymptomatic subjects at intermediate risk of coronary artery disease (CAD) is often uncertain. Re-stratification to a high- or low-risk category may enable optimization of preventative strategies. Coronary computed tomographic angiography (CCTA) enables a minimally invasive assessment of coronary artery plaque quantity and composition. Non-calcified plaque by CCTA is lipid-rich and more vulnerable to rupture and resultant acute coronary syndromes. The purpose of this study was to determine whether novel approaches to CAD risk stratification, such as plasma lipid profiling, may predict non-calcified plaque burden in intermediate risk subjects. CCTA and several markers of CAD (including plasma lipid profiling, carotid intima-media thickness, aortic pulse wave velocity, and high-sensitivity C-reactive protein) were prospectively performed in 100 asymptomatic patients at intermediate CAD risk according to the Framingham risk score. Segment stenosis scores (SSS) were calculated to evaluate the burden of total, calcified, and non-calcified coronary artery plaque. Non-calcified plaque was observed in 66 subjects and 158 (11%) of 1425 coronary artery segments. Eighteen lipid species demonstrated significant associations with non-calcified plaque burden, but not with total plaque or calcified plaque burden. No other marker of CAD was found to predict coronary artery plaque burden. Plasma lipidomic analysis can predict the burden of non-calcified coronary plaque in asymptomatic subjects at intermediate risk of CAD. Re-stratification of these patients by plasma lipid profiling may enable more appropriate and effective primary prevention management strategies.

TCT-588 Optical Coherence Tomography Guided Analysis of Coronary Artery Plaque Composition, Morphology and Burden and their Effect on ABSORB Bioresorbable Vascular Scaffold Expansion and Eccentricity.

TCT-588 Optical Coherence Tomography Guided Analysis of Coronary Artery Plaque Composition, Morphology and Burden and their Effect on ABSORB Bioresorbable Vascular Scaffold Expansion and Eccentricity.