Chronic exposure to high altitude and the presence of coronary ectasia in patients with ST elevation myocardial infarction

Objective

To evaluate the association between chronic exposure to high altitude and the presence of coronary ectasia (CE) in patients with ST-segment elevation myocardial infarction (STEMI) treated in a highly specialized cardiovascular reference hospital in Peru.

Materials and methods

Retrospective matched case-control study. The cases were patients with CE and controls without CE. The relationship between CE and chronic exposure to high altitude was evaluated considering intervening variables such as arterial hypertension, diabetes mellitus, dyslipidemia, smoking, and hematocrit values. Patients with chronic inflammatory pathologies, chronic obstructive pulmonary disease, and previous revascularization were excluded. Multivariate logistic regression was applied to obtain the OR value and their respective confidence intervals.

Results

Eighteen cases and 18 controls were studied, most of them were men with an average age of 65 years. Thirty-six percent of the population came from high altitude; in this group 76.9% had coronary ectasia of the infarct-related artery. The mean hematocrit value was slightly higher in the high-altitude native (46 ± 7% versus 42 ± 5%, p=0.094). Multivariate conditional logistic regression did not find a significant relationship between exposure to high altitude and the risk of presenting CE (OR:6.03, IC95%: 0.30-118, p=0.236).

Conclusions

In patients with STEMI, we found no association between chronic exposure to high altitude and coronary ectasia.

Next-generation sequencing of prolidase gene identifies novel and common variants associated with low prolidase in coronary artery ectasia

BACKGROUND

Decreased collagen biosynthesis and increased collagenolysis can cause ectasia progression in the arterial walls. Prolidase is a key enzyme in collagen synthesis; a decrease in prolidase activity or level may decrease collagen biosynthesis, which may contribute to ectasia formation. Considering that, the variations in PEPD gene encoding prolidase enzyme were evaluated by analyzing next-generation sequencing (NGS) for the first time together with known risk factors in coronary artery ectasia (CAE) patients.

METHODS

Molecular analysis of the PEPD gene was performed on genomic DNA by NGS in 76 CAE patients and 76 controls. The serum levels of prolidase were measured by the sandwich-ELISA technique.

RESULTS

Serum prolidase levels were significantly lower in CAE group compared to control group, and it was significantly lower in males than females in both groups (p < 0.001). On the other hand, elevated prolidase levels were observed in CAE patients in the presence of diabetes (p < 0.001), hypertension (p < 0.05) and hyperlipidemia (p < 0.05). Logistic regression analysis demonstrated that the low prolidase level (p < 0.001), hypertension (p < 0.02) and hyperlipidemia (p < 0.012) were significantly associated with increased CAE risk. We identified four missense mutations in the PEPD gene, namely G296S, T266A, P365L and S134C (novel) that could be associated with CAE. The pathogenicity of these mutations was predicted to be "damaging" for G296S, S134C and P365L, but "benign" for T266A. We also identified a novel 5'UTR variation (Chr19:34012748 G>A) in one patient who had a low prolidase level. In addition, rs17570 and rs1061338 common variations of the PEPD gene were associated with low prolidase levels in CAE patients, while rs17569 variation was associated with high prolidase levels in both CAE and controls (p < 0.05).

CONCLUSIONS

Our findings indicate that the low serum prolidase levels observed in CAE patients is significantly associated with PEPD gene variations. It was concluded that low serum prolidase level and associated PEPD mutations may be potential biomarkers for the diagnosis of CAE.

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.

The comparison of serum TGF-beta levels and associated polymorphisms in patients with coronary artery ectasia and normal coronary artery

Background

Coronary artery ectasia (CAE) is described as the enlargement of a coronary artery segment by 1.5 times or more, which is generally associated with the atherosclerotic process. Atherosclerotic changes lead to arterial remodeling result in CAE. In our study, we measured serum transforming growth factor (TGF)-β1 levels, which have a protective role against atherosclerosis. Further, we aimed to assess the TGF-β1 gene variants rs1800469 (–509C>T, c.−1347C>T) and rs1800470 (c.+29T>C, p.Pro10Leu, rs1982073), which might have an effect on TGF production. Overall, 2877 patients were screened including 56 patients with CAE and 44 patients with normal coronary arteries who were included in the study. Serum TGF-β1 levels were measured using ELISA and compared between two groups. Additionally, TGF-β1 rs1800469 and rs1800470 gene variations were determined using TaqMan® SNP Genotyping Assays.

Results

Serum TGF-β1 levels were significantly lower in patients with CAE than in controls (p=0.012). However, there was no difference in terms of the genotype and allele distributions of TGF-β1 rs1800469 and rs1800470 polymorphisms. Serum TGF-β1 levels were higher in individuals carrying the TGF-β1 rs1800470 G allele (GG+AG) than in individuals with normal homozygous AA genotype in the CAE group (p=0.012).

Conclusion

Our findings suggest that lower serum TGF-β1 levels are associated with an increased risk for CAE development and that TGF-β1 polymorphisms exert a protective effect. Furthermore, TGF-β1 rs1800470 G allele carriers were shown to have higher TGF-β1 levels in the CAE group. This suggests that having the G allele in the TGF-β1 rs1800470 polymorphism could prevent CAE development.

Association between Endothelial nitric oxide synthase and Hepatic lipase gene polymorphisms with the risk of coronary artery disease in Southern Iran population - A case control study

Coronary artery disease is a multifactorial genetic disease caused by the interaction between genetic and environmental factors. Angiography is the gold standard method for the diagnosis and determining the stage of cardiac disorder. The rs1800588 at the Hepatic Lipase gene and rs1799983 at the endothelial nitric oxide synthase (eNOS) gene are two candidate SNP that result in increased risk of this disease. The aim of this study was to find out the associations of the two mentioned polymorphisms with angiographically proven coronary artery patients in a southern Iranian population. In this study, this two polymorphisms in 287 patients and 229 matched controls were confirmed by angiography and analyzed. Genotype analysis was carried out by PCR and RFLP. Data showed that a significant difference for the eNOS gene polymorphism (p = 0.004) and a non-significant difference for the Hepatic lipase polymorphism (p = 0.261) and increasing severity of angiographic evidences of coronary artery disease were observed. Conclusively the significant association of the G894T with the narrowing of two or three coronary vessels of this patients in an Iranian population have been detected.

Comparison of mean platelet volume levels in coronary artery ectasia and healthy people: systematic review and meta-analysis

Coronary artery ectasia (CAE) is defined as the dilation of a segment of a coronary vessel to at least 1.5 times the diameter of its normal adjacent segment. Mean platelet volume (MPV) plays a role in acute coronary syndromes, with high MPV correlating to poor prognosis for acute thrombotic events and CAE. Several studies investigated the relationship between MPV and CAE, resulting in conflicting results. These results led us to systematically review all studies investigating the relationship between MPV and ectatic heart diseases by performing a meta-analysis study in order to report a unified result. This meta-analysis study investigated all case-control articles examining the relationship between MPV and CAE. All studies in the following databases published until January 31, 2018, were investigated: Science Direct, Scopus, PubMed, Google Scholar, and Web of Science. Following a quality control evaluation, 14 articles, all of which were published following studies performed in Turkey from 2007 to 2016, met the criteria for study inclusion. After pooling the results from all of the articles, a total standardized mean difference (SMD) value of 0.584 (95% CI, 0.219, 0.95) was obtained using the D+L pooled SMD, indicating a significant difference (P=0.002) between the two groups, with higher MPV values in ectatic patients when comparing to healthy individuals. Therefore, increased MPV levels were significantly related to CAE, suggesting that platelets, with their inflammatory and thrombotic activities, play a role in this disease. Therefore, anti-platelet and anti-inflammatory therapies may be effective in treating CAE.

Endothelial nitric oxide synthase Glu 298 Asp (G894T) and Apolipoprotein E gene polymorphism as possible risk factors for coronary heart disease among Egyptians

In Egypt, The prevalence of chronic heart disease (CHD) is 8.3%. It is the principal cause of death and is responsible for 22% of total mortality. The age-adjusted mortality rate is 174 per 100,000 of population. There are many studies on traditional risk factors and CHD in Egypt but the study of novel risk factors is deficient.

Objectives

The aim of the present case control study was to investigate the relation between CHD susceptibility and Endothelial Nitric Oxide Synthase (eNOS) Glu 298 Asp (G894T) and Apolipoprotein E (ApoE) gene polymorphism in a cohort of Egyptian individuals.

Methods

Genotyping of eNOS (Glu298Asp) and Apo E genes polymorphisms were done using polymerase chain reaction-restriction fragment length polymorphism (PCR–RFLP) method for 100 CHD cases and 100 age and sex matched healthy controls.

Results

A statistically significant association was observed between GT and TT genotypes of endothelial nitric oxide synthase gene with CHD with OR = 2.03 and 3.5; respectively. Also, carriers of E4 allele and especially E3/E4 genotype were at higher risk of CHD with OR = 3.3 for both. Significant association was also observed between the presence of combined GTE3E4 genotype and CHD with OR = 6.6.

Conclusion

GT and TT genotypes of endothelial nitric oxide synthase gene, E3/E4 genotype of Apo E gene polymorphism and combined GTE3E4 genotype can be considered risk factors for the development of CHD among Egyptians.

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.

Is there any association between vitamin D levels and isolated coronary artery ectasia?

Introduction

It has been postulated that low vitamin D levels are associated with coronary artery diseases. Coronary artery ectasia (CAE) is associated with atherosclerosis, congenital cardiac defects, immunological diseases and connective tissue diseases. In this study, we aimed to investigate whether there is an association between vitamin D and parathormone levels and isolated coronary artery ectasia and its extent.

Material and methods

The study included 93 participants: 47 patients (35 male, 12 female) with isolated CAE and 46 subjects (28 male, 18 female) with normal coronary arteries. Demographic characteristics of patients and controls were obtained from medical records, and Markis scores of patients were calculated. Serum vitamin D and parathormone levels were quantitatively measured by the paramagnetic particle chemiluminescence method.

Results

Serum vitamin D levels were found to be significantly lower in patients with isolated CAE than the control group (9.15 ±4.4 ng/ml, 13.35 ±5.9 ng/ml, p < 0.001). Parathormone levels were significantly higher in the CAE group than the control group (61.4 ±31.6, 48.7 ±25.5, p < 0.036). However, the study revealed no association between serum vitamin D levels and the extent of CAE according to the Markis classification (p = 0.23).

Conclusions

This study revealed that lower vitamin D levels and higher parathormone levels were associated with isolated CAE, but there was no association between vitamin D levels and the extent of CAE.

Serum nitric oxide levels in patients with coronary artery ectasia

Objective:

Serum levels of nitric oxide (NO) are decreased in patients with atherosclerosis and also are a risk factor for the development of atherosclerosis. Endothelial dysfunction and diffuse atherosclerosis have been proposed for the etiology of coronary artery ectasia (CAE). The purpose of this clinical trial was to determine the relationship between CAE and serum NO levels.

Methods:

This prospective controlled study was conducted between January 2008 and March 2012. Serum levels of NO were compared in 40 patients with CAE (mean age 60.1±7.3 years) and 40 patients with normal coronary arteries (mean age 57.6±5 years) as a control group. CAE was diagnosed when a segment of coronary artery was more than 1.5 times the diameter of the adjacent healthy segment. Patients with stenotic atherosclerotic plaques, slow coronary flow, previous history of revascularization, acute coronary syndromes, left ventricular dysfunction, valvular heart disease, and systemic diseases were not included in the study. The effect of NO on the outcome was studied by constructing a receiver operating characteristic (ROC) curve with CAE as the primary variable. Effects of different variables on CAE were calculated using binary logistics regression analysis.

Results:

Serum NO concentrations were significantly lower in patients with CAE than in the control group (42.1±20.1 µmol/L vs. 77.3±15.7 µmol/L, p<0.001). According to the results of the multivariate regression analysis, LDL and NO levels were identified as independent factors associated with CAE (OR=1.02, 95% CI 1–1.04, p=0.02 and OR=0.88, 95% CI 0.83–0.93, p=0.001, respectively). ROC analysis revealed that using a cut-off point of 63.3, NO level predicts CAE with a sensitivity of 87.5% and specificity of 90%.

Conclusion:

Our study indicates that decreased levels of NO are present in patients with CAE compared to patients with normal coronary arteries, supporting the hypothesis that decreased levels of NO might be associated with CAE development. (Anatol J Cardiol 2016; 16: 947-52)