New insights into molecular mechanisms of diffuse coronary ectasiae: A possible role for VEGF

Insights into lipid metabolism and immune-inflammatory responses in the pathogenesis of coronary artery ectasia

Coronary artery ectasia (CAE) is a rare finding that is associated with poor clinical outcomes (Kawsara et al. 2018), and disorders in lipid metabolism have been reported in CAE. Lipids constitute one of the three metabolite types that regulate bodily functions and are also powerful signaling molecules (Han 2016; Zhu et al. 2021) that affect immunoregulation and inflammatory responses via a series of transcription factors and signaling pathways (Barrera et al. 2013). Although abnormal lipid metabolism and immunoinflammatory responses have been reported in CAE, their roles in the pathogenic mechanisms underlying CAE are currently unclear.

Inflammatory Biomarkers in Coronary Artery Ectasia: A Systematic Review and Meta-Analysis

Isolated coronary artery ectasia (CAE) is a relatively rare clinical entity, the pathogenesis of which is poorly understood. More and more evidence is accumulating to suggest a critical inflammatory component. We aimed to elucidate any association between neutrophil to lymphocyte ratio and coronary artery ectasia. A systematic MEDLINE database, ClinicalTrials.gov, medRxiv, Scopus and Cochrane Library search was conducted: 50 studies were deemed relevant, reporting on difference in NLR levels between CAE patients and controls (primary endpoint) and/or on high-sensitive CRP, IL-6, TNF-a and RDW levels (secondary endpoint), and were included in our final analysis. (PROSPERO registration number: CRD42021224195). All inflammatory biomarkers under investigation were found higher in coronary artery ectasia patients as compared to healthy controls (NLR; SMD = 0.73; 95% CI: 0.27–1.20, hs-CRP; SMD = 0.96; 95% CI: 0.64–1.28, IL-6; SMD = 2.68; 95% CI: 0.95–4.41, TNF-a; SMD = 0.50; 95% CI: 0.24–0.75, RDW; SMD = 0.56; 95% CI: 0.26–0.87). The main limitations inherent in this analysis are small case-control studies of moderate quality and high statistical heterogeneity. Our findings underscore that inflammatory dysregulation is implicated in coronary artery ectasia and merits further investigation.

The Impact of C-Peptide and Diabetes Mellitus on Coronary Ectasia and Effect of Coronary Ectasia and C-Peptide on Long-Term Outcomes: A Retrospective Cohort Study

BACKGROUND

Coronary artery ectasia (CAE) is an entity frequently associated with atherosclerotic coronary artery disease (CAD) in clinical practice. Although it has common risk factors with atherosclerotic CAD in its development, the pathophysiology of CAE is not fully known and it is not seen in every CAD suggesting that different determinants may play a pivotal role in the development of CAD. This study aimed to reveal the impact of C-peptide and diabetes mellitus (DM) on CAE and the effect of C-peptide and coronary ectasia on long-term outcomes in patients who underwent coronary angiography.

METHODS

A total of 6611 patients who underwent coronary angiography were followed up retrospectively, and their major adverse cardiovascular event (MACE) status of an average of sixty months was recorded. According to their angiographic features, the patients were divided into two groups those with and without CAE. MACE development was accepted as the primary endpoint.

RESULTS

A total of 552 patients had CAE and MACE developed in 573 patients. Patients with CAE and higher C-peptide levels (Q4 + Q3) showed higher rates of MACE as compared to those without CAE and lower C-peptide levels (Q1 + Q2) (20.8% vs 7.6%; 70.1% vs 29.1%; p < 0.001, for both of them). In multivariate regression analysis, high C-peptide levels were determined as an independent risk factor for CAE (OR 2.417; 95% CI 2.212-2.641; p < 0.001). The Kaplan-Meier cumulative survival curves showed that the risks for MACE increased as the C-peptide levels increased. The Cox regression analysis for 5-years MACE related to the plasma C-peptide levels and presence of CAE, C-peptide, and CAE were found to be independent predictors of MACE (HR = 1.255, 95% CI: 1.164-1.336, p < 0.001 and HR = 1.012, 95% CI: 1.002-1.023, p=0.026, respectively).

CONCLUSION

Our study revealed that a high C-peptide level is an independent risk factor for CAE and that CAE and C-peptide are independent predictors for the development of MACE.

Involvement of Angiogenesis in the Pathogenesis of Coronary Aneurysms

The present study aimed to evaluate the plasma concentration of pro and antiangiogenic factors and their role in the pathogenesis of coronary artery abnormal dilation (CAAD). We measured the plasma concentration of matrix metalloproteinase-8 (MMP-8), transforming growth factor beta 1 (TGF-β1), Angiopoietin-2, vascular endothelial growth factor (VEGF), and fibroblast growth factor (FGF) using a sandwich ELISA technique in the plasma of patients with coronary artery abnormal dilation (CAAD, Group 1), coronary artery disease (CAD, Group 2), and normal coronary arteries (NCA, Group 3). Patients suffering from CAAD showed significantly higher plasma concentrations of VEGF (p = 0.002) than those from the control group. Both pathological angiogenesis and inflammation appear to be crucial in the pathogenesis of aneurysmal dilatation of the coronary arteries.

Endocan expression correlated with total volume of coronary artery dilation in patients with coronary artery ectasia

Introduction

Inflammation and angiogenesis disturbances are considered as factors contributing to the development of coronary artery ectasias (CAE). Endocan (endothelial cell-specific molecule-1 – ESM-1) regulates both inflammatory and angiogenetic processes. However, there are no data about the correlation between endocan level and the severity of CAE measured with total volume of coronary artery dilation.

Aim

To assess whether the severity of the inflammatory process measured as endocan concentration correlates with the total volume of CAE.

Material and methods

We selected prospectively a total of 43 consecutive patients with coronary artery ectasia from 2240 patients who underwent coronary angiography in our center. Determination of endocan was performed by using the Human Endothelial cell-specific Molecule 1 (ECSM1/ENDOCAN) ELISA Kit. 3D QCA (three-dimensional quantitative coronary angiography) was used for coronary lesion and aneurysm quantification. The total volume of dilation was defined as the volume of all aneurysms and ectasias of coronary arteries in 1 patient.

Results

The mean volume of all aneurysms in 1 patient was 677 ±878.7 mm³. The total aneurysm volume was positively strongly correlated with endocan concentration (Pearson correlation coefficient: 0.811; 2-tailed p < 0.001).

Conclusions

Endocan is a potential marker of vascular wall damage mainly as a result of inflammation in the course of atherosclerosis, but also vascular remodeling as a result of a disturbance of pro- and anti-angiogenic processes. Endocan level reflects the intensity of the above processes and therefore correlates with the severity of CAE, measured as the total volume of dilation.

The relationship between serum endocan levels and the presence/severity of isolated coronary artery ectasia

Objective

The aim of this study was to investigate the relationship between serum endocan levels and the presence and severity of isolated coronary artery ectasia (CAE).

Patients and methods

A total of 52 patients with CAE without obstructive coronary artery disease and 33 participants with a normal coronary artery were included in this study. The severity of CAE was graded according to Markis classification. Serum endocan levels were measured by enzyme-linked immunosorbent assay method.

Results

In multivariate regression analysis, high sensitivity C-reactive protein and endocan levels were found to be significantly associated with the presence of isolated CAE. However, there was no relationship between serum endocan levels and the severity of CAE according to Markis classification.

Conclusion

Plasma endocan levels may reflect the presence of isolated CAE, suggesting that endocan may be involved in the pathogenesis of isolated CAE.

Prognostic value of coronary collaterals in patients with acute coronary syndromes

BACKGROUND

The presence of good coronary collateral circulation (CCC) can protect and preserve myocardium from ischemia, increase myocardial contractility, and reduce adverse clinical events. However, its impact on mortality is still a topic of debate, particularly in acute coronary syndrome (ACS). The aim of this study was to investigate the association of CCC with cardiac risk factors and in-hospital mortality in patients hospitalized with a diagnosis of ACS.

METHODS

The study population included 2286 patients with ACS who underwent coronary angiography and were found to have at least 90% significant lesion in at least one major coronary artery. The CCC was graded according to the Rentrop classification. The patients were classified into a poor CCC group (Rentrop grades 0-1, n=1859) or a good CCC group (Rentrop grades 2-3, n=427).

RESULTS

Patients with good CCC had more high-risk patient characteristics such as older age, higher rate of Killip class of at least 2 at admission, lower left ventricular ejection fraction, and impaired renal functions compared with the patients with poor CCC. In multivariate analysis, the presence of good CCC [odds ratio (OR): 2.000; 95% confidence interval: 1.116-3.585; P=0.020], left ventricular ejection fraction less than 40% (OR: 2.381; P=0.003), Killip class of at least 2 at admission (OR: 3.609; P<0.001), age of at least 65 years (OR: 2.975; P=0.003), and hemoglobin (OR: 0.797; P=0.003) were independent predictors of in-hospital mortality.

CONCLUSION

In contrast to previous studies, our study did not confirm a beneficial role of good CCC in patients with ACS; the presence of good CCC was even independently associated with increased in-hospital mortality in the multivariate analysis.

Molecular and cellular insights into the pathogenesis of coronary artery ectasia

Coronary artery ectasia describes a local or diffuse dilatation of the epicardial coronary arteries. This review summarizes the molecular and cellular mechanisms involved in the pathogenesis of coronary artery ectasia. Better identification of the pathophysiologic steps will shed light into the clinical significance and may have direct implications for the management strategies of this disease. Additionally, understanding the underlying etiology may help to improve treatment modalities specific to coronary artery ectasia.

Cytokine Disturbances in Coronary Artery Ectasia Do Not Support Atherosclerosis Pathogenesis

BACKGROUND

Coronary artery ectasia (CAE) is a rare disorder commonly associated with additional features of atherosclerosis. In the present study, we aimed to examine the systemic immune-inflammatory response that might associate CAE.

METHODS

Plasma samples were obtained from 16 patients with coronary artery ectasia (mean age 64.9 ± 7.3 years, 6 female), 69 patients with coronary artery disease (CAD) and angiographic evidence for atherosclerosis (age 64.5 ± 8.7 years, 41 female), and 140 controls (mean age 58.6 ± 4.1 years, 40 female) with normal coronary arteries. Samples were analyzed at Umeå University Biochemistry Laboratory, Sweden, using the V-PLEX Pro-Inflammatory Panel 1 (human) Kit. Statistically significant differences (p < 0.05) between patient groups and controls were determined using Mann-Whitney U-tests.

RESULTS

The CAE patients had significantly higher plasma levels of INF-γ, TNF-α, IL-1β, and IL-8 (p = 0.007, 0.01, 0.001, and 0.002, respectively), and lower levels of IL-2 and IL-4 (p < 0.001 for both) compared to CAD patients and controls. The plasma levels of IL-10, IL-12p, and IL-13 were not different between the three groups. None of these markers could differentiate between patients with pure (n = 6) and mixed with minimal atherosclerosis (n = 10) CAE.

CONCLUSIONS

These results indicate an enhanced systemic pro-inflammatory response in CAE. The profile of this response indicates activation of macrophages through a pathway and trigger different from those of atherosclerosis immune inflammatory response.

Systemic inflammatory impact of periodontitis on acute coronary syndrome

AIM

A causative relationship between acute coronary syndrome (ACS) and periodontitis has yet to be defined. The aim of this study was to assess differences in levels of serum cytokines between individuals with or without ACS or periodontal comorbidity.

MATERIAL AND METHODS

In a case-control study, individuals with ACS (78 individuals, 10.3% females) and matching healthy controls (78 individuals, 28.2% females) were included. Medical and dental examinations were performed to diagnose ACS and periodontitis. Serum levels of cytokines were assessed, using Luminex technology.

RESULTS

A diagnosis of periodontitis in the ACS and control group was diagnosed in 52.6% and 12.8% of the individuals, respectively. The unadjusted odds-ratio that individuals with ACS also had periodontitis was 7.5 (95% CI: 3.4, 16.8, p < 0.001). Independent of periodontal conditions, individuals with ACS had significantly higher serum levels of IL8 (mean: 44.3 and 40.0 pg/ml) and vascular endothelial growth factor (VEGF) (mean: 82.3 and 55.3 pg/ml) than control individuals. A diagnosis of periodontitis made no difference in serum cytokine expressions.

CONCLUSION

Elevated serum levels of VEGF were associated with ACS. Serum cytokine expression in individuals with ACS is unrelated to periodontal conditions.

The Investigation of Relationship between Coronary Artery Ectasia, Benign Prostatic Enlargement, and Lower Urinary Tract Symptoms

OBJECTIVE

To investigate benign prostatic enlargement (BPE) and lower urinary tract symptoms (LUTS) in patients with coronary artery ectasia (CAE). The relation between CAE, BPE, and LUTS has not been studied so far.

METHODS

We investigated BPE and LUTS symptoms in 47 men with CAE, 45 men with coronary artery disease (CAD), and 47 male controls with normal coronary arteries. LUTS was evaluated by the International Prostate Symptom Score (IPSS). BPE was evaluated with transabdominal ultrasonography. CAD was defined as myocardial infarction and angiographically diagnosed coronary disease. CAE was defined as being without any stenotic lesions with a visual assessment of the coronary arteries showing a luminal dilatation ≥1.5 fold of the adjacent normal coronary segments.

RESULTS

Prostate volume was higher in CAE and CAD patients compared with that of the control subjects, respectively (41.0 ± 10.4 vs 33.5 ± 9.4 cm(3); 39.1 ± 10.3 vs 33.5 ± 9.4 cm(3); P = .0001); total IPSS was higher in CAD and CAE patients compared with that of the control subjects (P = .0001). Postmictional residual urine volume was higher in CAE and CAD patients compared with that of the control subjects (P = .002).

CONCLUSION

We showed that patients with CAE have higher prostate volume, IPSS, and postmictional residual urine volume compared with those of controls with normal coronary angiograms. This study proposes that BPE, LUTS, and CAE maybe different disorders to a common vascular pathology and endothelial dysfunction. This study showed that BPE and LUTS were frequently seen in CAE at least as much as in CAD. Therefore, LUTS and BPE should be kept in mind for CAE patients in follow-ups.

Inflammatory mediators of coronary artery ectasia

The exact mechanisms underlying coronary artery ectasia (CAE) remain uncertain. This study aims to investigate whether and how inflammatory mediators play a role in the pathogenesis of CAE. The data sources of this study were located by literature searches on MEDLINE, Highwire Press and Google search engine for the year range 2000-2013. The most sensitive of the four types of plasma inflammatory mediators were cell adhesion molecules and systemic inflammatory markers followed by cytokines, while proteolytic substances were the least sensitive indicators of CAE. Hypersensitive C-reaction protein, homocysteine, intercellular adhesion molecule 1, vascular cell adhesion molecule 1, matrix metalloproteinase-9, tissue inhibitor of metalloproteinase-2, vascular endothelial growth factor and neopterin levels were significantly higher in CAE and coronary artery disease (CAD) patients than in controls without CAE. The percentage of granulocytes was higher in CAE, in comparison with individuals with normal coronary arteries. Polymerase chain reaction determination of angiotensin converting enzyme genotypes showed that the DD genotype was more prevalent in CAE patients than in CAD patients, while prevalence of the I allele was higher in CAD than in CAE patients. CAE is more a result of inflammatory processes than of extracellular matrix degradation, as demonstrated by investigations of plasma inflammatory mediators, activation markers and angiotensin converting enzyme genotypes. Contemporary theories are unable to explain CAE's predilection for the right coronary artery or the occurrence of multi-vessel and multi-segment involvement.

Coronary artery dilation in sickle cell disease

OBJECTIVE

To evaluate the prevalence of coronary artery dilation in children with sickle cell disease (SCD).

STUDY DESIGN

This is a retrospective analysis performed in patients, between 10 and 19 years old, with SCD who underwent a routine transthoracic echocardiographic evaluation over a 20-month period. The left main, left anterior descending, and proximal right coronary artery diameters, as well as clinical and laboratory variables and other echocardiographic results were collected. Echocardiographic measurements were converted to z scores by using information from a large control population of normal children. Coronary artery ectasia (CAE) was defined as a coronary artery diameter z score ≥ 2. The patients with CAE were compared with those without CAE by using univariate and multivariate analyses.

RESULTS

Seventeen of 96 patients with SCD (17.7%) had CAE. There were no differences in sex, age, height, weight, body surface area, or genotype between those with and those without CAE. Patients with CAE had larger left ventricular end-diastolic dimension, shortening fraction, septal thickness, posterior wall thickness, mass, mass-to-volume ratio, and white blood cell count. Multivariate analysis revealed that the mass-to-volume ratio and elevated white blood cell count were associated with CAE.

CONCLUSION

CAE is common in SCD and is associated with left ventricular hypertrophy and inflammation.

Assessment of coronary veins in patients with isolated coronary artery ectasia by antegrade coronary venous angiography

BACKGROUND

Coronary artery ectasia (CAE) is characterized by an abnormal dilatation of the coronary arteries. The most common cause of CAE is atherosclerosis but other possible etiologies include congenital abnormalities and inflammatory and connective tissue disease. Earlier studies have documented the association of CAE with the presence of aneurysms in other vascular beds. However, cardiac venous system in patients with isolated CAE has not been studied earlier. In this study, we aimed to assess coronary venous vessels by antegrade coronary venous angiography in patients with isolated CAE.

METHODS

Twenty-four patients with isolated CAE without significant stenosis and 21 age-matched and sex-matched controls without CAE were included in this study. The anatomy of the coronary venous system was imaged in a left anterior oblique view at an angle of 45° by antegrade coronary angiography.

RESULTS

Patients with isolated CAE had significantly larger coronary veins compared with control individuals with angiographically normal coronary arteries (coronary sinus ostium: 10.1 ± 1.0 vs. 8.5 ± 2.2 mm, respectively, P=0.003; coronary sinus mid level: 7.9 ± 1.4 vs. 6.5 ± 1.6, respectively, P=0.003; great cardiac vein: 5.6 ± 1.0 vs. 4.3 ± 0.8, respectively, P=0.001; middle cardiac vein: 3.9 ± 1.3 vs. 3.7 ± 1.4, respectively, P=0.52; posterior or lateral vein: 3.2 ± 1.1 vs. 2.4 ± 0.7, respectively, P=0.016).

CONCLUSION

We have shown for the first time a significant dilatation in the coronary veins in patients with isolated CAE, suggesting the presence of a more extensive vascular destruction in the coronary circulation.

Matrix metalloproteinases and inflammatory markers in coronary artery ectasia: their relationship to severity of coronary artery ectasia

OBJECTIVE

Although underlying mechanisms of coronary artery ectasia (CAE) are clearly unknown, destruction of extracellular matrix may be responsible for the ectasia formation. Thus, we investigated the role of matrix metalloproteinases (MMP), tissue inhibitor of matrix metalloproteinases (TIMP-1), and inflammatory markers [high-sensitive C-reactive protein, interleukins (ILs)] in CAE patients.

METHODS

This study consisted of 28 consecutive CAE patients, 27 obstructive coronary artery disease (CAD) patients, and 22 controls with normal coronary arteries undergoing cardiac catheterization. Plasma levels of MMP-3, MMP-9, TIMP-1, and inflammatory markers were measured.

RESULTS

Plasma level of MMP-3 was significantly higher in CAE patients compared with both CAD patients and controls (17.2+/-6.1, 11.2+/-3.2, and 9.2+/-3.4 ng/ml, respectively, both P=0.001) and so did MMP-9 level (27.4+/-5.9, 24.8+/-4.4, and 20.6+/-4.6 ng/ml, respectively, both P<0.05). IL-6 level was also higher in CAE patients than in controls (60.9+/-22.1 vs. 36.1+/-21.5 pg/ml, P=0.001) but were comparable in CAE and CAD patients. Plasma high-sensitive C-reactive protein, IL-1, and TIMP-1 levels were similar in three groups. MMP-3 levels correlated with diffuse (r=0.46, P=0.01) and multivessel ectasia (r=0.45, P=0.02).

CONCLUSION

Our results suggest that the increased level of MMP-3, MMP-9, and IL-6 may be responsible for ectasia formation in patients with CAE.

Pathogenetic mechanisms of coronary ectasia

Coronary ectasia is defined as local or generalized aneurysmal dilatation of the coronary arteries. The present review summarizes the molecular, cellular and vascular mechanisms which are involved in the pathobiology of coronary ectasia. Coronary ectasia likely represents an exaggerated form of expansive vascular remodeling (i.e. excessive expansive remodeling) in response to atherosclerotic plaque growth. Enzymatic degradation of the extracellular matrix of the media is the major pathophysiologic process that leads to ectasia. Atherosclerotic lesions within ectatic regions of the coronary arteries appear to be highly inflamed high-risk plaques with proclivity to rupture. Better understanding of the pathogenetic processes involved in coronary ectasia is anticipated that will provide a further insight into the clinical significance and natural history of this entity, and may also have direct clinical implications in the management and follow-up strategy of this condition.

Cyclic strain-mediated matrix metalloproteinase regulation within the vascular endothelium: a force to be reckoned with

The vascular endothelium is a dynamic cellular interface between the vessel wall and the bloodstream, where it regulates the physiological effects of humoral and biomechanical stimuli on vessel tone and remodeling. With respect to the latter hemodynamic stimulus, the endothelium is chronically exposed to mechanical forces in the form of cyclic circumferential strain, resulting from the pulsatile nature of blood flow, and shear stress. Both forces can profoundly modulate endothelial cell (EC) metabolism and function and, under normal physiological conditions, impart an atheroprotective effect that disfavors pathological remodeling of the vessel wall. Moreover, disruption of normal hemodynamic loading can be either causative of or contributory to vascular diseases such as atherosclerosis. EC-matrix interactions are a critical determinant of how the vascular endothelium responds to these forces and unquestionably utilizes matrix metalloproteinases (MMPs), enzymes capable of degrading basement membrane and interstitial matrix molecules, to facilitate force-mediated changes in vascular cell fate. In view of the growing importance of blood flow patterns and mechanotransduction to vascular health and pathophysiology, and considering the potential value of MMPs as therapeutic targets, a timely review of our collective understanding of MMP mechanoregulation and its impact on the vascular endothelium is warranted. More specifically, this review primarily summarizes our current knowledge of how cyclic strain regulates MMP expression and activation within the vascular endothelium and subsequently endeavors to address the direct and indirect consequences of this on vascular EC fate. Possible relevance of these phenomena to vascular endothelial dysfunction and pathological remodeling are also addressed.