High-sensitivity C-reactive protein and plaque composition in patients with stable angina pectoris: a virtual histology intravascular ultrasound study

Cardiovascular Risk Factors from Another Point of View

Cardiovascular diseases remain the main cause of death in western societies. This contributes to the appearance of new diagnostic and treatment methods addressed to reduce the burden of cardiovascular diseases. In the last decades new imaging methods have emerged; furthermore, routine biomarkers were found to be useful in cardiovascular risk stratification. Data reviewed in this article emphasize the multifactorial etiology of cardiovascular disease. The authors describe the role of inflammation in the precipitation and progression of atherosclerosis and atrial fibrillation. Affordable and well-known inflammatory markers can be used alone or in combination with new imaging methods for a better cardiovascular risk stratification. Coronary computed tomographic angiography findings and inflammatory markers are capable to identify patients with high risk of major adverse cardiovascular events or atrial fibrillation. Furthermore, they also have an important role in the choice of treatment strategy and follow-up.

C-reactive protein levels and plaque regression with evolocumab: Insights from GLAGOV

Objective

On-treatment levels of high sensitivity C-reactive protein (hsCRP) in statin-treated patients predict plaque progression and the prospective risk of atherosclerotic cardiovascular events. Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors produce additional LDL-C lowering, reduce plaque burden and improve cardiovascular outcomes in statin-treated patients. It is unknown whether residual systemic inflammation attenuates their favorable effects on plaque burden.

Methods

GLAGOV compared the effects of treatment for 78 weeks with evolocumab or placebo on progression of coronary atherosclerosis in statin-treated patients with coronary artery disease.

Clinical demographics, biochemistry and changes in both the burden (percentage atheroma volume (PAV), total atheroma volume (TAV), n ​= ​413) and composition (n ​= ​162) of coronary plaque were evaluated in evolocumab-treated patients according to baseline hsCRP strata (<1, 1–3, >3 ​mg/L).

Results

The study cohort comprised 413 evolocumab-treated patients (32% low [<1 ​mg/L], 41% intermediate [1–3 ​mg/L] and 27% high [>3 ​mg/L] baseline hsCRP levels). Patients in the highest hsCRP stratum were more likely to be female and had a higher prevalence of diabetes, hypertension, and the metabolic syndrome. LDL-C levels were similar across the groups, however participants with higher hsCRP levels had higher triglyceride and lower HDL-C levels at baseline. At follow-up, the change in PAV from baseline (−0.87% [low] vs. −0.84% [intermediate] vs. −1.22% [high], p ​= ​0.46) and the proportion of patients experiencing any degree of regression (65.9% vs. 63.5% vs. 63.1%, p ​= ​0.88) was similar across hsCRP strata and when evaluated by levels of achieved LDL-C. There were no serial differences in plaque composition by hsCRP strata.

Conclusion

The ability of evolocumab to induce regression in statin-treated patients is not attenuated by the presence of enhanced systemic inflammation. This underscores the potential benefits of intensive lipid lowering, even in the presence of heightened inflammatory states.

Clinical approach to the inflammatory etiology of cardiovascular diseases

Inflammation is an obligatory marker of arterial disease, both stemming from the inflammatory activity of cholesterol itself and from well-established molecular mechanisms. Raised progenitor cell recruitment after major events and clonal hematopoiesis related mechanisms have provided an improved understanding of factors regulating inflammatory phenomena. Trials with inflammation antagonists have led to an extensive evaluation of biomarkers such as the high sensitivity C reactive protein (hsCRP), not exerting a causative role, but frequently indicative of the individual cardiovascular (CV) risk. Aim of this review is to provide indication on the anti-inflammatory profile of agents of general use in CV prevention, i.e. affecting lipids, blood pressure, diabetes as well nutraceuticals such as n-3 fatty acids. A crucial issue in the evaluation of the benefit of the anti-inflammatory activity is the frequent discordance between a beneficial activity on a major risk factor and associated changes of hsCRP, as in the case of statins vs PCSK9 antagonists. In hypertension, angiotensin converting enzyme inhibitors exert an optimal anti-inflammatory activity, vs the case of sartans. The remarkable preventive activity of SLGT-2 inhibitors in heart failure is not associated with a clear anti-inflammatory mechanism. Finally, icosapent ethyl has been shown to reduce the CV risk in hypertriglyceridemia, with a 27 % reduction of hsCRP. The inflammation-based approach to arterial disease has considerably gained from an improved understanding of the clinical diagnostic strategy and from a better knowledge on the mode of action of numerous agents, including nutraceuticals.

Matrix Metalloproteinase 9 as a Predictor of Coronary Atherosclerotic Plaque Instability in Stable Coronary Heart Disease Patients with Elevated Lipoprotein(a) Levels

We sought to investigate whether levels of matrix metalloproteinases (MMPs) and their inhibitors predict coronary atherosclerotic plaque instability, as assessed by intravascular ultrasound (IVUS) virtual histology during coronary angiography. Blood samples were collected before angiography in 32 subjects (mean age 56 ± 8 years) with stable coronary heart disease (CHD) and elevated lipoprotein(a) (Lp(a), 94 ± 35 mg/dL). Levels of high-sensitivity C-reactive protein (hsCRP), apolipoprotein B100 (apoB100), MMP-7, MMP-9, tissue inhibitor of metalloproteinases (TIMP)-1, and TIMP-2 were determined using commercially available enzyme-linked immunosorbent assay kits. Results. The morphology of a total of sixty coronary lesions was assessed by virtual histology IVUS imaging. Eleven (18%) plaques in nine (28%) patients were classified as plaques with an unstable phenotype or a thin-cap fibroatheroma. Age, low-density lipoprotein cholesterol, apoB100, MMP-7, and MMP-9 levels were positively associated with necrotic core volume. Conversely, there was a negative relationship between MMP-7 and -9 levels and fibrous and fibro-fatty tissue volume. Multivariate regression analysis revealed that MMP-9 is a strong independent predictor of atherosclerotic plaque instability in stable CHD patients. In stable CHD patients with elevated Lp(a), MMP-9 levels are positively associated with the size of the necrotic core of coronary atherosclerotic plaques.

Clinical significance of hepatic steatosis according to coronary plaque morphology: assessment using controlled attenuation parameter

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) plays a significant role in coronary atherosclerosis, independent of shared metabolic risk factors. The measurement of the controlled attenuation parameter (CAP) has shown to allow early and noninvasive detection of NAFLD at subclinical stage. We evaluated the significance of CAP-defined NAFLD in association with the presence of any type of coronary plaques and different plaque compositions.

METHODS

We conducted a retrospective cohort of apparently healthy subjects who had liver Fibroscan and coronary computed tomography during health screening exams.

RESULTS

A greater number of subjects with CAP-defined NAFLD was found in group with coronary plaques (61.3% vs. 73.5%, p = 0.005 without vs. with any type of plaque). From multivariate regression model, CAP ≥ 222 dB/m was an independent and significant parameter associated with the presence of coronary plaques, after adjusting possible confounders (OR 1.624, 95% 1.047-2.518, p = 0.030). Interestingly, CAP ≥ 222 dB/m was significantly associated with non-calcified plaque (adjusted OR 3.528, 95% CI 1.463-8.511, p = 0.005), whereas it was not significant in calcified plaques (p = 0.171).

CONCLUSION

CAP-defined NAFLD is independently associated with coronary plaques, especially non-calcified plaques. The association between NAFLD and non-calcified plaques suggests that particular attention should be given to the subjects with NAFLD for primary prevention.

Apolipoprotein B correlates with intra-plaque necrotic core volume in stable coronary artery disease

Objective

To determine the relationship between plaque composition and low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), apolipoprotein B (Apo-B), and Apo-A1 using virtual-histology intravascular ultrasound (VH-IVUS).

Methods

We assessed plaque composition in patients with stable coronary artery disease (SCD) admitted to our hospital for percutaneous coronary intervention (PCI) between November 1, 2012, and March 10, 2015. Before PCI, fibrous (FI), fibrofatty (FF), necrotic core (NC), and dense calcium (DC) regions were evaluated using VH-IVUS, and the contributions of each to the culprit lesion volume were recorded. Plasma LDL-C, HDL-C, Apo-B, and Apo-A1 levels were assessed before PCI. The relationship between the regions on VH-IVUS and plasma lipid levels was assessed. Patients were categorized into low Apo-B (LAB) and high Apo-B (HAB) groups, based on the overall cohort median Apo-B level.

Results

We enrolled 115 patients (median Apo-B, 91 mg/dL, male n = 88) with 57 and 58 patients in the LAB (Apo-B ≤ 90 mg/dL) and HAB (Apo-B ≥ 91 mg/dL) groups, respectively. Vessel, plaque, and %NC volumes were significantly greater in the HAB group than in the LAB group. The %FI, %FF, and %DC volumes were similar in both groups. In all 115 patients, the %NC volume correlated with LDL-C (r = 0.2353, P = 0.0114) and Apo-B (r = 0.2487, P = 0.0074) but not with HDL-C and Apo A-1. The high-sensitivity C-reactive protein level tended to be higher in the HAB group than in the LAB group. Multiple regression analysis showed that being male, Apo-A1, and Apo-B were significant predictors of %NC volume extent.

Conclusions

Elevated Apo-B level was related to the %NC in target coronary artery lesions in SCD patients, suggesting a role of Apo-B as a biomarker of unstable plaque in this population.

EFFECTS OF PHYSICAL TRAINING ON THE MYOCARDIUM OF FEMALE LDL KNOCKOUT OVARIECTOMIZED MICE

ABSTRACT Introduction: The emergence of coronary heart disease increases with menopause, physical inactivity and with dyslipidemia. It is known that physical training promotes the improvement of cardiovascular functions. Objective: The purpose of this study was to investigate the effects of aerobic physical training on the left ventricle in female LDL knockout ovariectomized mice. Methods: Thirty animals were divided into 6 groups (n=5), namely, sedentary non-ovariectomized control; sedentary ovariectomized control; trained ovariectomized control; sedentary non-ovariectomized; sedentary ovariectomized; and trained ovariectomized. We analyzed the mean nuclear volume parameters, the cross sectional area of the myocytes, the apparent density of the capillaries, interstitium, myocytes and collagen fibers. Results: The results show that for the density of the number of nuclei, the physical activity decreased to values close to the ovariectomized control group. Regarding the mean nuclear volume and the average area of myocytes, training and ovariectomy promoted the elevation of these values but hypercholesterolemia was lower. the volume density of myocytes, hypercholesterolemia showed an increase of these values as well as the training. There was no change in the volumetric density of the capillaries and the density of collagen fibers. The training caused the decrease in the density of the interstitial volume, and the hypercholesterolemia changed to a smaller one than the control group. Conclusion: We concluded that the moderate aerobic activity or the training time used in our study were not sufficient to generate significant alterations in the hypercholesterolemic group.

The influence of low-grade inflammation on platelets in patients with stable coronary artery disease

Inflammation is likely to be involved in all stages of atherosclerosis. Numerous inflammatory biomarkers are currently being studied, and even subtle increases in inflammatory biomarkers have been associated with increased risk of cardiovascular events in patients with coronary artery disease (CAD). Low-grade inflammation may influence both platelet production and platelet activation potentially leading to enhanced platelet aggregation. Thrombopoietin is considered the primary regulator of platelet production, but it likely acts in conjunction with numerous cytokines, of which many have altered levels in CAD. Previous studies have shown that high-sensitive C-reactive protein (CRP) independently predicts increased platelet aggregation in stable CAD patients. Increased levels of CRP, fibrinogen, interleukin-6, stromal cell-derived factor-1, CXC motif ligand 16, macrophage migration inhibitory factor, RANTES, calprotectin, and copeptin have been associated with increased risk of cardiovascular events in CAD patients. Additionally, some of these inflammatory markers have been associated with enhanced platelet activation and aggregation. However, CRP and other inflammatory markers provide only limited additional predictive value to classical risk factors such as smoking, blood pressure, and cholesterol levels. Existing data do not clarify whether inflammation simply accompanies CAD and increased production and aggregation of platelets, or whether a causal relationship exists. In this review, we provide a comprehensive overview of inflammatory markers in stable CAD with particular emphasis on platelet production, activation, and aggregation in CAD patients.

Relationship Between Serum Inflammatory Marker Levels and the Dynamic Changes in Coronary Plaque Characteristics After Statin Therapy

BACKGROUND

The mechanism of statin for atheroma stabilization remains unclear. We aimed to assess the relationship between on-treatment changes in serum inflammatory biomarker levels and plaque composition in differed nonculprit coronary lesions.

METHODS AND RESULTS

The changes in serum biochemical values, and intravascular ultrasound data were evaluated in 218 patients with virtual histology (VH)-intravascular ultrasound-defined fibroatheroma-containing segments after 12-month rosuvastatin treatment. When stratifying patients into quartiles according to the change in high-sensitivity C-reactive protein (hsCRP), there was a significant positive linear relationship for the changes in %necrotic core (coefficient, 1.31; standard error, 0.54) and %dense calcium volumes (coefficient, 0.80; standard error, 0.27), but a negative linear relationship for the changes in %fibrous (coefficient, -0.94; standard error, 0.45) and %fibrofatty volumes (coefficient, -1.17; standard error, 0.56; all P<0.05). The decrease in hsCRP (-1.2±3.9 versus 0.5±3.4 mg/L; P=0.02) was greater in those without VH-defined thin-cap fibroatheroma (TCFA, defined as >30° of necrotic core abutting the lumen in 3 consecutive slices) than those with VH-TCFA at follow-up. Diabetes mellitus, a larger normalized total atheroma volume, and the presence of VH-TCFA at baseline predicted the presence of VH-TCFA at follow-up (odds ratio, 4.01, 1.18, and 9.21, respectively; all P<0.05), whereas the change in hsCRP showed a trend (odds ratio, 1.19; P=0.07). The change in low-density lipoprotein-cholesterol had no relationship with the changes in hsCRP or plaque compositions.

CONCLUSIONS

With 12-month rosuvastatin therapy, a greater hsCRP reduction (not low-density lipoprotein-cholesterol) was associated with a greater decrease in %necrotic core volume and the absence of VH-TCFA, indicating a link between the anti-inflammatory action of statin and plaque stabilization by reducing NC and reinforcing fibrous cap.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT00997880.

Fibrinogen in relation to degree and composition of coronary plaque on intravascular ultrasound in patients undergoing coronary angiography

OBJECTIVE

The aim of this study was to provide additional insight into the role of fibrinogen in coronary artery disease by investigating the associations between plasma fibrinogen with both degree and composition of coronary atherosclerosis as determined by virtual histology-intravascular ultrasound.

PATIENTS AND METHODS

In 581 patients undergoing coronary angiography for acute coronary syndrome (ACS) or stable angina pectoris, preprocedural blood samples were drawn for fibrinogen, C-reactive protein (CRP), interleukin-6, and plasminogen activator inhibitor-1 measurements, and virtual histology-intravascular ultrasound of a nonculprit coronary artery was performed. The degree [plaque volume, plaque burden (PB), and lesions with PB≥70%] and the composition of coronary atherosclerotic plaque (fibrous, fibrofatty, dense calcium, necrotic core tissue, and thin-cap fibroatheroma lesions) were assessed.

RESULTS

Fibrinogen showed a tendency toward a positive association with PB [β (95% CI): 2.55 (-0.52-5.61) increase in PB per ln(g/l) fibrinogen, P=0.09], which was driven significantly by an association in the ACS subgroup [β (95% CI): 4.11 (0.01-8.21) increase in PB per ln(g/l) fibrinogen, P=0.049]. Fibrinogen was also related to the presence of lesions with PB 70% or more in both the full cohort [OR (95% CI): 2.27 (1.17-4.43), P=0.016] and ACS patients [OR (95% CI): 2.92 (1.17-7.29), P=0.022]. All associations were independent of established cardiovascular risk factors, but not CRP. Interleukin-6 and plasminogen activator inhibitor-1 did not provide incremental value to fibrinogen when examining the associations with degree of atherosclerosis. Substantial associations with plaque composition were absent.

CONCLUSION

Fibrinogen is associated with degree of coronary atherosclerosis, especially in ACS patients. However, whether this association is independent of CRP might be questioned and needs further investigation.

Circulating Microparticles and Coronary Plaque Components Assessed by Virtual Histology Intravascular Ultrasound of the Target Lesion in Patients with Stable Angina

High levels of microparticles (MPs) circulate in the blood of patients with atherosclerotic diseases where they can serve as potential biomarkers of vascular injury and cardiovascular outcome. We used virtual histology intravascular ultrasound (VH-IVUS) to evaluate the relationship between the levels of circulating MPs and the coronary plaque composition in patients with stable angina. We included 35 patients with stable angina (22 men, age 64 ± 9 years) and a de novo target lesion. Preintervention gray-scale and VH-IVUS analysis was performed across the target lesion. Volumetric analysis was performed over a 10-mm-long segment centered at the minimum luminal site. Blood samples were obtained from the femoral artery before coronary angioplasty. MPs were measured using a solid-phase capture assay from a commercial kit. We divided participants into either a low MPs group or high MPs group based on the median value of MPs. There was no significant difference in baseline characteristics between the groups. The plaque burden and remodeling index were similar between the groups. The presence of VH-IVUS-derived thin-cap fibroatheroma was not different between the groups. The percentage of the necrotic core (NC) was significantly higher in the high MPs group than in the low MPs group, both in planar (17.0 ± 8.8% vs. 24.1 ± 6.9%, p = 0.012) and volumetric analyses (17.0 ± 4.8% vs. 22.1 ± 4.3%, p = 0.002). Circulating MPs were positively correlated with the percentage of the NC area at the minimal luminal site (r = 0.491, p = 0.003) and the percentage of the NC volume (r = 0.496, p = 0.002). Elevated levels of circulating MPs were associated with the amount of NC in the target lesion in those with stable angina, suggesting a potential role of circulating MPs as a biomarker for detecting unstable plaque in patients with stable angina.

Clinical usefulness of novel serum and imaging biomarkers in risk stratification of patients with stable angina

Inflammatory mediators appear to be the most intriguing yet confusing subject, regarding the management of patients with acute coronary syndromes (ACS). The current inflammatory concept of atherosclerotic coronary artery disease (CAD) led many investigators to concentrate on systemic markers of inflammation, as well as imaging techniques, which may be helpful in risk stratification and prognosis assessment for cardiovascular events. In this review, we try to depict many of the recently studied markers regarding stable angina (SA), their clinical usefulness, and possible future applications in the field.

Plaque characteristics and arterial remodeling in coronary and peripheral arterial systems

BACKGROUND

Few studies have examined plaque characteristics among multiple arterial beds in vivo. The purpose of this study was to compare the plaque morphology and arterial remodeling between coronary and peripheral arteries using gray-scale and radiofrequency intravascular ultrasound (IVUS) at clinical presentation.

METHODS AND RESULTS

IVUS imaging was performed in 68 patients with coronary and 93 with peripheral artery lesions (29 carotid, 50 renal, and 14 iliac arteries). Plaques were classified as fibroatheroma (VH-FA) (further subclassified as thin-capped [VH-TCFA] and thick-capped [VH-ThCFA]), fibrocalcific plaque (VH-FC) and pathological intimal thickening (VH-PIT). Plaque rupture (13% of coronary, 7% of carotid, 6% of renal, and 7% of iliac arteries; P = NS) and VH-TCFA (37% of coronary, 24% of carotid, 16% of renal, and 7% of iliac arteries; P = 0.02) were observed in all arteries. Compared with coronary arteries, VH-FA was less frequently observed in renal (P < 0.001) and iliac arteries (P < 0.006). Lesions with positive remodeling demonstrated more characteristics of VH-FA in coronary (84% vs. 25%, P < 0.001), carotid (72% vs. 20%, P = 0.001), and renal arteries (42% vs. 4%, P = 0.001) compared with those with intermediate/negative remodeling. There was positive relationship between remodeling index and percent necrotic area in all four arteries.

CONCLUSIONS

Atherosclerotic plaque phenotypes were heterogeneous among four different arteries; renal and iliac arteries had more stable phenotypes compared with coronary artery. In contrast, the associations of remodeling pattern with plaque phenotype and composition were similar among the various arterial beds.

Correlations between coronary plaque tissue composition assessed by virtual histology and blood levels of biomarkers for coronary artery disease

PURPOSE

We investigated correlations of coronary plaque composition determined by virtual histology (VH) intravascular ultrasound (IVUS) and blood levels of biomarkers that represent the vulnerability of coronary plaques.

MATERIALS AND METHODS

Pre- and postprocedural blood levels of high sensitivity C-reactive protein, soluble CD40 ligand (sCD40L), matrix metalloproteinase-9, and neopterin were measured in 70 patients with stable angina (SA) or unstable angina (UA) who were undergoing percutaneous coronary intervention (PCI) for single lesions. We evaluated the data for correlations between these biomarkers and necrotic core contents in PCI target lesions analyzed by VH.

RESULTS

Clinical characteristics, IVUS, VH, and biomarker blood levels were not different between the SA and the UA group except for more frequent previous statin use (52.3% vs. 23.1%, p=0.017) and lower remodeling index in the SA group (0.98±0.09 vs. 1.10±0.070, p<0.001). Among the biomarkers evaluated, only pre-PCI neopterin level showed a weakly significant correlation with the absolute volume of the necrotic core (r=0.320, p=0.008). Pre- and post-PCI blood levels of sCD40L (r=0.220, p=0.072; r=0.231, p=0.062) and post-PCI blood level of neopterin (r=0.238, p=0.051) showed trends toward weakly positive correlations with the absolute volume of necrotic core.

CONCLUSION

We found a weakly positive correlation between the pre-PCI neopterin level and necrotic core volume in the PCI-target lesion. The clinical implications of our findings need to be investigated in further studies.