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Apoprotein B, Small‐Dense LDL and Impaired HDL Remodeling Is Associated With Larger Plaque Burden and More Noncalcified Plaque as Assessed by Coronary CT Angiography and Intravascular Ultrasound With Radiofrequency Backscatter: Results From the ATLANTA I Study

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Apoprotein B-containing lipoproteins are atherogenic, but atheroprotective functions of apoprotein A-containing high-density lipoprotein (HDL) particles are poorly understood. The association between lipoproteins and plaque components by coronary computed tomography angiography (CTA) and intravascular ultrasound with radiofrequency backscatter (IVUS/VH) has not been evaluated. Quantitative, 3-dimensional plaque measurements were performed in 60 patients with CTA and IVUS/VH. Apoproteins, lipids, and HDL subpopulations were measured with 2-dimensional (2D) gel electrophoresis, and correlation was assessed with univariate and multivariable models. ApoB particles were associated with a higher proportion of noncalcified plaque (NCP) and a lower proportion of calcified plaque (small, dense low-density lipoprotein cholesterol and high-density NCP: r=0.3, P=0.03; triglycerides and low-density NCP: r=0.34, P=0.01). Smaller, dense, lipid-poor HDL particles were associated with a shift from calcified plaque to NCP on CTA (α3-HDL% and low-density NCP: r=0.32, P=0.02) and with larger plaque volume on IVUS/VH (α4-HDL%: r=0.41, P=0.01; α3-HDL%: r=0.37, P=0.03), because of larger dense calcium (α4-HDL%: r=0.37, P=0.03), larger fibrous tissue (α4-HDL%: r=0.34, P=0.04), and larger necrotic core (α4-HDL%: r=0.46, P<0.01; α3-HDL%: r=0.37, P=0.03). Larger lipid-rich HDL particles were associated with less low-density NCP on CTA (α2-HDL%: r=-0.34, P=0.02; α1-HDL%: r=-0.28, P=0.05), with smaller plaque volume on IVUS/VH (pre-α2-HDL: r=-0.33, P=0.05; α1-HDL%: r=-0.41, P=0.01; pre-α2-HDL: r=-0.33, P=0.05) and with less necrotic core (α1-HDL: r=-0.42, P<0.01; pre-α2-HDL: r=-0.38, P=0.02; α2-HDL: r=-0.35, P=0.03; pre-α1-HDL: r=-0.34, P=0.04). Pre-β2-HDL was associated with less calcification and less stenosis by both modalities. ApoB and small HDL particles are associated with larger plaque burden and more noncalcified plaque, whereas larger HDL and pre-β2-HDL particles are associated with plaque burden and less noncalcified plaque by both CTA and IVUS/VH.
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... 12,13 Lipoprotein subclasses are also associated with CVD risk 11,13 and, more recently, have been shown to be related to coronary plaque composition as measured by multiple different imaging modalities. [20][21][22] In the ATLANTA (Assessment of Tissue Characteristics, Lesion Morphology, and Hemodynamics by Angiography With Fractional Flow Reserve, Intravascular Ultrasound and Virtual Histology, and Noninvasive Computed Tomography in Atherosclerotic Plaques) study of 60 individuals without oCAD presenting with chest pain, small, dense LDL and small HDL are associated with HRP features (namely, larger plaque volume, more noncalcified plaque, and higher volume of necrotic core) on coronary CTA and intravascular ultrasound, whereas larger HDL particles are associated with lower plaque volume and lower volume of necrotic core. 21 Supportive of the role of impaired reverse cholesterol transport, in a separate study using carotid magnetic resonance imaging assessment to detect HRP, the Chicago Healthy Aging Study found that HDL efflux capacity correlates with large and medium HDL subclasses; however, after multivariable adjustment, neither efflux capacity nor subclasses associate with HRP. ...
... [20][21][22] In the ATLANTA (Assessment of Tissue Characteristics, Lesion Morphology, and Hemodynamics by Angiography With Fractional Flow Reserve, Intravascular Ultrasound and Virtual Histology, and Noninvasive Computed Tomography in Atherosclerotic Plaques) study of 60 individuals without oCAD presenting with chest pain, small, dense LDL and small HDL are associated with HRP features (namely, larger plaque volume, more noncalcified plaque, and higher volume of necrotic core) on coronary CTA and intravascular ultrasound, whereas larger HDL particles are associated with lower plaque volume and lower volume of necrotic core. 21 Supportive of the role of impaired reverse cholesterol transport, in a separate study using carotid magnetic resonance imaging assessment to detect HRP, the Chicago Healthy Aging Study found that HDL efflux capacity correlates with large and medium HDL subclasses; however, after multivariable adjustment, neither efflux capacity nor subclasses associate with HRP. 23 In another study of statin-treated patients with diabetes, the triglyceride/HDL-C ratio was significantly associated with HRP features detected by frequency-domain optical coherence tomography. ...
... Our major findings center around NMR-derived HDL particle subclasses. It is possible that other methods to measure HDL subclasses might determine different associations with HRP; however, given that our study is consistent with one that demonstrated similar associations of large HDL particles measured by gel electrophoresis with HRP, 21 we believe this is unlikely. We also note that the associations of HDL subclasses with HRP were attenuated when including HDL-C in our multivariable regression models. ...
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BACKGROUND More than half of major adverse cardiovascular events (MACE) occur in the absence of obstructive coronary artery disease and are often attributed to the rupture of high‐risk coronary atherosclerotic plaque (HRP). Blood‐based biomarkers that associate with imaging‐defined HRP and predict MACE are lacking. METHODS AND RESULTS Nuclear magnetic resonance–based lipoprotein particle profiling was performed in the biomarker substudy of the PROMISE (Prospective Multicenter Imaging Study for Evaluation of Chest Pain) trial (N=4019) in participants who had stable symptoms suspicious for coronary artery disease. Principal components analysis was used to reduce the number of correlated lipoproteins into uncorrelated lipoprotein factors. The association of lipoprotein factors and individual lipoproteins of significantly associated factors with core laboratory determined coronary computed tomographic angiography features of HRP was determined using logistic regression models. The association of HRP‐associated lipoproteins with MACE was assessed in the PROMISE trial and validated in an independent coronary angiography biorepository (CATHGEN [Catheterization Genetics]) using Cox proportional hazards models. Lipoprotein factors composed of high‐density lipoprotein (HDL) subclasses were associated with HRP. In these factors, large HDL (odds ratio [OR], 0.70 [95% CI, 0.56–0.85]; P <0.001) and medium HDL (OR, 0.84 [95% CI, 0.72–0.98]; P =0.028) and HDL size (OR, 0.82 [95% CI, 0.69–0.96]; P =0.018) were associated with HRP in multivariable models. Medium HDL was associated with MACE in PROMISE (hazard ratio [HR], 0.76 [95% CI, 0.63–0.92]; P =0.004), which was validated in the CATHGEN biorepository (HR, 0.91 [95% CI, 0.88–0.94]; P <0.001). CONCLUSIONS Large and medium HDL subclasses and HDL size inversely associate with HRP features, and medium HDL subclasses inversely associate with MACE in PROMISE trial participants. These findings may aid in the risk stratification of individuals with chest pain and provide insight into the pathobiology of HRP. REGISTRATION URL: https://clinicaltrials.gov ; Unique identifier: NCT01174550
... In contrast, those lipoproteins associated with reverse cholesterol transport are able to clean out excess cholesterol from macrophages in atherosclerotic lesions, thus offering an atheroprotective effect. The lipoprotein particles consist of lipid components, including cholesterol, cholesterylester, phospholipids, and triglycerides, and protein components like Apo A, B, C, and E. The critical mechanism of the atherogenic dyslipidemia paradigm is that the lipoprotein particles contained by Apo B are atherogenic due to the physical binding of Apo B to proteoglycans in the arterial wall while the HDL particles contained in Apo A are atheroprotective through removing cholesterol from macrophages in the arterial wall and preventing LDL oxidation and maladaptive inflammation [27]. Apo A is mainly synthesized by the liver and intestines and secreted into blood circulation. ...
... Apo A is mainly synthesized by the liver and intestines and secreted into blood circulation. In the circulation, Apo A undergoes some remodeling processes facilitated by some enzymes including plasma lipid transfer protein, lecithin-cholesterol acyltransferase, and cholesterol ester transfer protein and finally matures to more lipid-rich and larger HDL particles before performing its atheroprotective function [27]. This theory explains our findings that the epicardial fat volume is negatively correlated with HDL or Apo A but positively correlated with Apo B/ Apo A. TG is positively correlated with Apo B but negatively correlated with HDL, and thus, TG may indirectly affect the epicardial fat and consequently the prevalence of three-vessel coronary lesions through affecting Apo B and HDL. ...
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... Moreover, HDL dialyzed with calcium inhibited closely by 80% the oxidation of low-density lipoprotein (LDL) [21]. Interestingly, results from the ATLANTA I study, using intravascular ultrasound (IVUS) and coronary tomography observed some HDL subpopulation can be associated to more cholesterol plaque content and less calcified lesions [22]. ...
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The pathophysiology and genetic regulation of this process are both evaluated in this chapter along with the key mechanisms at play. Vascular calcification is highly associated with cardiovascular disease mortality, particularly in high risk patients with diabetes and chronic kidney diseases (CKD). In blood vessels, intimal calcification is associated with atherosclerosis, whereas medial calcification is a non-occlusive process which leads to increased vascular stiffness and reduced vascular compliance. In the valves, calcification of the leaflets can change the mechanical properties of the tissue and result in stenosis. For many decades, vascular calcification has been noted as a consequence of aging. Recent research suggests that arterial calcification is an independent cardiovascular risk factor (CRF) for morbidity and mortality. New studies have pointed out the existence of complex physiopathological mechanisms that flocks inflammation, oxidation, the release of chemical mediators, and genetic factors that promote the osteochondrogenic differentiation of vascular smooth muscle cells (VSMC).
... Interestingly, results from the ATLANTA I study, analyzing the relationship between lipoproteins and plaque components by computed tomography angiography (CTA) and intravascular ultrasound (IVUS), showed that apoB-containing lipoproteins, as well as HDL-P, were involved [40]. Indeed, apoB particles were associated with a higher proportion of non-calcified plaque and a lower proportion of calcified plaques. ...
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... A significant increase in LDL particle size was observed with Omega-3 compared with Control at week 8 (p = 0.0040). We consider the increase in LDL particle size to be beneficial for patients with dyslipidemia as sdLDL is associated with larger plaque burden and more noncalcified plaque in patients receiving coronary computed tomography angiography and intravascular ultrasound with radiofrequency backscatter [20]. In the sdLDL fraction, a significant decrease was observed with Omega-3 compared with Control at week 8 in the concentration of cholesterol (p = 0.0004) and phospholipid (p = 0.0047); however, no significant decrease in the concentration of TG, free cholesterol and TG/cholesterol ratio was observed. ...
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Since we previously reported that lower levels of HDL-C may be most useful for predicting coronary artery disease (CAD) as assessed by multi-detector row computed tomography (MDCT), we sought to confirm, among the levels of LDL-C, HDL-C, non-HDL-C (total cholesterol minus HDL-C) and the ratio of LDL-C to HDL-C (LDL-C/HDL-C), which is most closely related to the presence of CAD. The subjects consisted of 506 consecutive patients with suspected CAD who underwent MDCT with (+) or without (-) statin treatment. The levels of LDL-C in the statin (-) group were similar in categories I, II and III according to the Japan Atherosclerosis Society (JAS) Guidelines 2007, whereas the levels of HDL-C significantly decreased and LDL-C/HDL-C significantly increased as the category number increased. In the statin (-) group, the prevalence of CAD in categories I, II and III was 0, 16 and 33%, respectively (p=0.0018 for trend), in patients with good control of LDL-C levels according to the Guidelines. Multivariate logistic regression analysis was per-formed to examine the association between the presence of CAD and 11 possible factors. Age and HDL-C in the statin (-) group, and HDL-C in the statin (+) group were identified as significant independent variables that correlated with the presence of CAD. Receiver-operating characteristic curve analysis in the statin (-) and statin (+) groups showed a higher area under the curve for HDL-C than for LDL-C, non-HDL-C or LDL-C/HDL-C. In particular, the cut-off levels of HDL-C with the greatest sensitivity and specificity for the diagnosis of CAD in the statin (+) group were 55 mg/dL (sensitivity 0.816, specificity 0.510). HDL-C levels are most closely associated with the presence of CAD. In particular, we need to perform coronary CT for suspected CAD patients with lower HDL-C levels under statin treatment.
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We sought to determine significant relations between atherogenic lipoproteins and the contribution of calcified plaque (CP), mixed plaque (MP), and noncalcified plaque (NCP) to the total plaque (TP) burden in patients without previous coronary artery disease. From 823 adult patients without previously established coronary artery disease (52% receiving statin therapy, 34% asymptomatic) but with visible coronary plaque on coronary computed tomographic angiography, we obtained segmental CP, MP, NCP, and TP counts from contrast-enhanced, electrocardiographic-gated computed tomography. Multivariate linear regression analysis was used to determine the associations of clinical factors and lipoprotein levels to CP, MP, and NCP counts and CP/TP, MP/TP, and NCP/TP count ratios. Age, male gender, diabetes, smoking, and statin therapy were significantly associated with the CP count (p <0.001, p <0.001, p = 0.049, p = 0.016, and p = 0.003, respectively). Low-density lipoprotein (LDL) cholesterol was significantly associated with MP and NCP counts (all p values </=0.002). LDL cholesterol was also the only variable to demonstrate significant concurrent relations with CP/TP, MP/TP, and NCP/TP ratios, including an inverse association with CP/TP (p = 0.008) and a positive association with MP/TP (p = 0.032). Analyses using non-high-density lipoprotein cholesterol in place of LDL cholesterol yielded similar results. In conclusion, among the traditional clinical factors used to estimate cardiovascular event risk, LDL cholesterol is associated with an increased MP and NCP burden and is the sole variable that independently predicted relative predominance of CP, MP, and NCP, suggesting a potentially important role for lipoprotein levels in modulating the type of detectable coronary arterial plaque.
Article
The purpose of this study was to investigate whether multidetector computed tomography (MDCT) can noninvasively help assess thin-cap fibroatheroma (TCFA). Plaque rupture and thrombus formation play key roles in the onset of acute coronary syndrome. TCFA is recognized as a precursor lesion for plaque rupture, and MDCT angiography can potentially help identify plaques prone to rupture. We enrolled 105 patients with coronary artery disease (acute coronary syndromes, n = 31; stable angina pectoris, n = 74). Culprit lesions were assessed by both MDCT and optical coherence tomography (OCT). Patients were divided into a TCFA and a non-TCFA group according to OCT findings; clinical and MDCT observations were compared for 2 groups. There were no differences in patients' characteristics between the 2 groups. OCT revealed 25 TCFAs at the culprit site in 105 patients. Acute coronary syndrome was more frequent in the TCFA group than in the non-TCFA group (52% vs. 23%, p = 0.01). High-sensitive C-reactive protein was higher in the TCFA group (0.32 +/- 0.32 mg/dl vs. 0.17 +/- 0.16 mg/dl, p < 0.001). Positive remodeling identified by MDCT was observed more frequently in the TCFA group than in the non-TCFA group (76% vs. 31%, p < 0.001). Computed tomography attenuation value of the culprit plaque in the TCFA group was lower than that in the non-TCFA group (35.1 +/- 32.3 HU vs. 62.0 +/- 33.6 HU, p < 0.001). The frequency of ring-like enhancement in the TCFA group was higher than in the non-TCFA group (44% vs. 4%, p < 0.0001). The sensitivity, specificity, positive predictive value, and negative predictive value of ring-like enhancement for detecting TCFA are 44%, 96%, 79%, and 85%, respectively. By stepwise regression, the ring-like enhancement, high-sensitive C-reactive protein, and diagnosis of acute events were associated with the presence of TCFA at the culprit site. MDCT can identify differences in plaque morphologies between TCFA and non-TCFA. From our results, MDCT may provide for the noninvasive assessment of vulnerable plaque.