Coronary Collaterals Research Articles

Vieussens’ Arterial Ring with Coronary Artery Disease: Affecting Clinical Decision Making

Background: Incidental findings on imaging are becoming increasingly common. An example of such a finding is a Vieussens’ arterial ring. It was first described by Raymond de Vieussens as a collateral pathway between the conus branch of the right coronary artery and the proximal right ventricular branch of the left anterior descending coronary artery. This finding can be of significance in patients with coronary artery disease. Case Presentation: The authors present the case of a 79-year-old male who experienced atrial tachyarrhythmia with a complex coronary artery fistula between the left anterior descending artery, conus branch, and the main pulmonary artery, indicating a Type Ib Vieussens’ arterial ring. Type Ib means that it is accompanied by vascular pathology. The patient also had additional coronary disease in the left anterior descending artery, further increasing the complexity of the case. Conclusion: Coronary collaterals offer an alternative source of blood supply in cases of additional coronary artery disease and can impact patient prognosis. Chronic myocardial ischaemia and increased shear stresses are causes of collateral circulations. Vieussens’ arterial rings can be subdivided into four groups. Only one case report of a Type Ib Vieussens’ ring has been identified on literature review, where the patient presented with a non-ST elevation myocardial infarction, unlike the atrial tachyarrhythmia in this case. Given their rarity, specifically of Type Ib, there is increased difficulty in establishing an appropriate management pathway, thus having great impact on clinical decision making.

Abstract 714: Effects Of Canagliflozin On Myocardial Microvascular Density, Oxidative Stress, And Proteomic Profile

Objective: Sodium-glucose cotransporter-2 inhibitors (SGLT2i) are cardioprotective, and canagliflozin (CANA), an SGLT2i, has been shown to improve perfusion, AMPK signaling, and oxidative stress in chronically ischemic myocardium. The aim of this study is to determine the effects of CANA in nonischemic myocardium on coronary collateralization, oxidative stress, and other molecular pathways determined by proteomic profiling. Methods: Yorkshire swine underwent placement of an ameroid constrictor to the left circumflex artery. Two weeks later, pigs received no drug (CON, n=8) or 300mg CANA daily (n=8). Treatment continued for five weeks, followed by tissue harvest of nonischemic myocardium. Results: CANA was associated with a strong trend towards decreased capillary density (p=0.05) compared to CON, with no changes in arteriolar density (p>0.5). Reduced capillary density did not correlate with reduced perfusion (p>0.5). Total oxidative stress was reduced with CANA (22% decrease, p=0.028). In the CANA group, there was a trend towards increased p-eNOS (p=0.19) and eNOS (p=0.13), without a change in p-eNOS/eNOS ratio (p=0.69), p-Akt (p=0.96), Akt (p=0.38), and p-Akt/Akt ratio (p=0.57). There was no change in p-ERK1/2 (p=0.96), with a decrease in total ERK1/2 (p=0.002) and increase in the p-ERK1/2/ERK1/2 ratio (p=0.001). There were no changes in expression of p-AMPK (p=0.33), AMPK (p=0.8), with a trend towards increased ratio of p-AMPK/AMPK (p=0.12). Proteomics analysis identified 2819 common proteins, of which 120 were upregulated and 425 were downregulated with CANA (p<0.01). Pathway analysis demonstrated wide regulation of metabolic proteins (Figure). Conclusions: The beneficial effects of CANA on myocardial perfusion and AMPK signaling in chronically ischemic myocardium are not found in nonischemic territory, despite improvements in oxidative stress. Metabolic proteins are widely regulated in nonischemic myocardium with CANA.

The impact of the apelinergic system in coronary collateral formation.

This study aims to examine the relationship between the development of coronary collateral circulation and serum elabela levels. Between January 2020 and December 2021, a total of 50 control individuals (29 males, 21 females; mean age: 63.2±10.0 years; range, 52 to 73 years) with no significant coronary artery disease as confirmed by angiography (Group 1) and 100 patients (55 males, 45 females; mean age: 66.6±9.6 years; range, 56 to 75 years) with coronary artery disease were included. The patients were further divided into two equal groups according to the Rentrop classification as poor (Group 2) and good coronary collateral circulation (Group 3). All groups were compared in terms of several parameters, particularly serum elabela levels. Serum elabela levels were found to be statistically higher in the group with good collateral than the other groups (p<0.05). Low serum elabela levels increased the risk of developing weak collaterals by 2.43 times. The elabela protein is directly related to good collateral development and can be considered a potential agent for treatment.

Past Myocardial Infarctions and Gender Predict the LVEF Regardless of the Status of Coronary Collaterals: An AI-Informed Research

BACKGROUND: The degree of the development of coronary collaterals is long considered an alternate – that is, a collateral – source of blood supply to an area of the myocardium threatened with vascular ischemia or insufficiency. Hence, the coronary collaterals are beneficial but can also promote harmful (adverse) effects. For instance, the coronary steal effect during the myocardial hyperemia phase and that of restenosis following coronary angioplasty. OBJECTIVES: Our study explores the contribution of coronary collaterals – if any exist – while considering other potential predictors, including demographics and medical history, toward the left ventricular (LV) dysfunction measured through the LV ejection fraction (LVEF). METHODS: Our cross-sectional design study used convenience sampling of 100 patients (n = 100; a male-to-female ratio of 4:1). We conducted frequentist inference statistics using IBM-SPSS version 24 and Microsoft Office Excel 2016 with the analysis ToolPak plugin; we ran parallel neural networks (supervised machine learning (ML)) and a two-step clustering (non-supervised ML) for robust conjoint inference with frequentist statistics. RESULTS: The past incidents of myocardial infarction (p = 0.036) and gender (p = 0.072) influenced the LVEF; both are significant predictors at a 90% confidence interval. We found that gender and past incidents of MI influenced the LVEF regardless of the status of coronary collaterals. Our study did not yield any positive or significant findings concerning the status of coronary collaterals or the coronary circulation dominance patterns. CONCLUSION: Regardless of the status of coronary collaterals, we verified that the female gender is protective of the LV function, contrary to the past infarction incidents that predispose to a deteriorated LV function. Our study’s innovation relates to its status as the first study from India to explore the coronary collaterals and the ejection fraction while incorporating frequentist statistics and narrow artificial intelligence to infer reliable results.

The Roles of Bone Marrow-Derived Stem Cells in Coronary Collateral Growth Induced by Repetitive Ischemia.

Many clinical trials have attempted to use stem cells to treat ischemic heart diseases (IHD), but the benefits have been modest. Though coronary collaterals can be a "natural bypass" for IHD patients, the regulation of coronary collateral growth (CCG) and the role of endogenous stem cells in CCG are not fully understood. In this study, we used a bone marrow transplantation scheme to study the role of bone marrow stem cells (BMSCs) in a rat model of CCG. Transgenic GFP rats were used to trace BMSCs after transplantation; GFP bone marrow was harvested or sorted for bone marrow transplantation. After recovering from transplantation, the recipient rats underwent 10 days of repetitive ischemia (RI), with echocardiography before and after RI, to measure cardiac function and myocardial blood flow. At the end of RI, the rats were sacrificed for the collection of bone marrow for flow cytometry or heart tissue for imaging analysis. Our study shows that upon RI stimulation, BMSCs homed to the recipient rat hearts' collateral-dependent zone (CZ), proliferated, differentiated into endothelial cells, and engrafted in the vascular wall for collateral growth. These RI-induced collaterals improved coronary blood flow and cardiac function in the recipients' hearts during ischemia. Depletion of donor CD34+ BMSCs led to impaired CCG in the recipient rats, indicating that this cell population is essential to the process. Overall, these results show that BMSCs contribute to CCG and suggest that regulation of the function of BMSCs to promote CCG might be a potential therapeutic approach for IHD.

The Effects of Exercise on Coronary Collateral Circulation: A Review.

The effects of exercise on the cardiovascular system are multifaceted and complex. It is well-documented that exercise can reduce mortality related to cardiovascular pathology. One anatomical structure that has been implicated in this process is the coronary collateral circulation. The goal of this review is to evaluate the current literature on the effects of exercise on human coronary collateral circulation. A search for literature was conducted on the databases Science Direct and PubMed using the terms: coronary collateral, collateral, exercise, physical activity, resistance training, endurance training, and collateral artery. Research that had the primary outcome of assessing human coronary collateralization secondary to exercise was included. Research in which the effect of exercise was not the primary outcome was excluded. As a result, a total of 13 research papers on the effects of exercise on coronary collateral circulation were included. Thirteen original research papers were reviewed. The mean age range in all studies was between 48 and 64 years old. There was a predominance of male participants, with a total of 597 male patients and 108 female patients across all studies. It was found that initial research underestimated the effect of exercise on coronary collateral circulation due to a lack of sensitive assessment methods. With the introduction of sensitive measures like the collateral flow index (CFI) and Rentrop scoring, results have shown that coronary collateral function can be increased with exercise. Exercise has been shown to enhance coronary collateral function. There is limited evidence as to which type, duration, or intensity of exercise is most favourable to enhance coronary collateral function. There is also relatively little data on the effects of exercise in the female population and those over the age of 65 years. More research is required to determine the specific effects of exercise on coronary collateral circulation in various age groups, genders, co-morbidities, specific exercise modalities, durations, intensities, and the effect of pharmacotherapy.

SerpinG1: A Novel Biomarker Associated With Poor Coronary Collateral in Patients With Stable Coronary Disease and Chronic Total Occlusion.

Background This study aimed to explore predictive biomarkers of coronary collateralization in patients with chronic total occlusion. Methods and Results By using a microarray expression profiling program downloaded from the Gene Expression Omnibus database, weighted gene coexpression network analysis was constructed to analyze the relationship between potential modules and coronary collateralization and screen out the hub genes. Then, the hub gene was identified and validated in an independent cohort of patients (including 299 patients with good arteriogenic responders and 223 patients with poor arteriogenic responders). Weighted gene coexpression network analysis showed that SERPING1 in the light-cyan module was the only gene that was highly correlated with both the gene module and the clinical traits. Serum levels of serpinG1 were significantly higher in patients with bad arteriogenic responders than in patients with good arteriogenic responders (472.53±197.16 versus 314.80±208.92 μg/mL; P<0.001) and were negatively associated with the Rentrop score (Spearman r=-0.50; P<0.001). Receiver operating characteristic curve analysis indicated that the area under the curve was 0.77 (95% CI, 0.72-0.81; P<0.001) for serum serpinG1 in prediction of bad arteriogenic responders. After adjusting for traditional cardiovascular risk factors, serum serpinG1 levels (per SD) remained an independent risk factor for bad arteriogenic responders (odds ratio, 2.20 [95% CI, 1.76-2.74]; P<0.001). Conclusions Our findings illustrate that SERPING1 screened by weighted gene coexpression network analysis was associated with poor collateralization in patients with chronic total occlusion.

CXCL5 gene polymorphisms and coronary collateralization

BackgroundThe presence of coronary collateralization is heterogenous, even amongst those with similar degrees of epicardial coronary artery stenoses. We hypothesized that genetic variation of CXCL5, a chemokine that mediates angiogenesis, is associated with coronary collateralization. MethodsWe genotyped subjects undergoing coronary angiography for single nucleotide polymorphisms of CXCL5 and determined the presence of spontaneously visible coronary collaterals. ResultsSubjects with collaterals had less angina (46 % vs 59 %, p = 0.006), and prior percutaneous coronary intervention (34 % vs 47 %, p = 0.010), and more hyperlipidemia (90 % vs 82 %, p = 0.018), peripheral arterial disease (25 % vs 17 %, p = 0.041), congestive heart failure (16 % vs 8 %, p = 0.007), and multi-vessel coronary artery disease (41 % vs 24 %, p = 0.0001) compared to those without collaterals. Multi-vessel disease and hyperlipidemia were positive predictors of angiographically visible collaterals while being a carrier of the CXCL5 polymorphism was a negative predictor. ConclusionsCoronary collateralization may, at least in part, be genetically determined.

The relationship between good collateral development and magnesium/phosphate ratio in chronic total occlusion

Objective: Coronary collateral formation can be triggered by many acquired factors such as ischemia and growth factors, which ultimately manifests as differences in the quality of the coronary collateral circulation (CCC) in patients. Low magnesium (Mg) levels can increase endothelial cell dysfunction and potentially increase the risk of thrombosis and atherosclerosis. However, it has been reported that high serum phosphate (P) levels are correlated with the development of atherosclerosis and mortality. In this article, we aimed to reveal the relationship between CCC quality and Mg/P ratio in chronic total occlusion (CTO).&#x0D; Methods: A total of 269 patients with detected CTO in coronary angiography between March 2014 and June 2018 were included in the study. The patients were divided into two groups as group I (127 patients) and group II (142 patients) according to the Rentrop classification. The study is a retrospective, observational study.&#x0D; Results: In the multivariable regression analysis; smoking (p=0.004), triglyceride (p

A CASE OF VENTRICULAR SEPTAL RUPTURE AFTER ACUTE MYOCARDIAL INFARCTION

When ventricular septal rupture (VSR) complicates acute myocardial infarction the mortality is usually high. Reperfusion therapy has reduced its incidence. However if VSR has developed then rapid diagnosis, aggressive medical management, and surgical intervention are required to optimize recovery and survival. In the era before reperfusion therapy, septal rupture complicated 1 to 3 percent of acute myocardial infarctions. Among the 41,021 patients in the Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries (GUSTO-I) trial, ventricular septal rupture was suspected in 140 patients (0.34 percent) and confirmed by a retrospective review in 84 (0.2 percent). Thus, reperfusion therapy has decreased the incidence of septal rupture. Septal rupture occurs more frequently with anterior wall acute myocardial infarction than other types of acute myocardial infarction. Risk factors for septal rupture included hypertension, advanced age (60 to 69 years), female sex and the absence of a history of angina or myocardial infarction. Angina or previous infarction may lead to myocardial preconditioning as well as to the development of coronary collaterals, both of which reduce the likelihood of septal rupture. In patients undergoing thrombolysis advanced age, female sex, and the absence of smoking are often associated with an increased risk of septal rupture, whereas the absence of antecedent angina has not been associated with an increased risk. In the GUSTO-I trial, there was a nonlinear relation between the systolic and diastolic blood pressures at enrolment and septal rupture, since hypertension and extensive myocardial infarction and right ventricular infarction are also risk factors for septal rupture

The association of new atherosclerosis markers with coronary collaterals in chronic total occlusion patients

Objectives: In the present study, we investigated the relationship between mentioned markers and chronic total occlusion collateral development. Patients and methods: A total of 243 patients (210 males, 33 females; mean age: 63.3±11.5; range, 51 to 76 years) who underwent coronary angiography due to typical chest pain or myocardial ischemia detected in noninvasive stress tests and diagnosed with ≥1 major coronary artery occlusion between January and September 2020 were included in the cross-sectional observational study. The angiographic collateral index was determined according to the Cohen-Rentrop classification. The patients were divided into two groups according to the sufficiency of collateral development: the well-developed collaterals group (n=155) and the poor-developed collaterals group (n=88). Results: Statistically significant parameters in univariate logistic regression analysis were evaluated with multivariate (stepwise) logistic regression analysis; as a result, presence of chronic total occlusion in left anterior descending artery (odds ratio [OR]=2.447; 95% confidence interval [CI], 1.160-5.162; p=0.019), total number of occlusions (OR=3.503; 95% CI, 1.445-8.494; p=0.006), left ventricular ejection fraction (OR=1.056; 95% CI, 1.022-1.091; p=0.001), and the atherogenic index of plasma (OR=0.017; 95% CI, 1.022-1.091; p&lt;0.001) were independently associated with well-developed collaterals. Although the triglyceride-glucose index had statistical significance in the univariate analysis, it was not detected as an independent variable in the multivariate analysis. The monocyte-lymphocyte ratio was not significant in the univariate analysis. Conclusion: Of the new atherosclerosis markers, only the atherogenic index of plasma had an independent association with poor collateral development.

An isolated congenital absence of right pulmonary artery associated with pulmonary hypertension with coronary collaterals: A case report

Unilateral absence of pulmonary artery (UAPA) resulting from a defect in the aortic arch's embryogenesis. Patients who survive into adulthood is rare. Herein, we presented a case of UAPA with pulmonary hypertension in a 49-year old female.

Role of collateral circulation in maintaining and restoring the left ventricular function and modern methods for its assessment

The coronary blood flow plays an important role in protecting the myocardium from ischemia and maintaining the cardiomyocyte function in the event of occlusion of one of the epicardial arteries. It also has a potential for restoring the contractile function during subsequent myocardial revascularization, which requires its more detailed research. Most methods for assessing coronary collaterals are carried out to define the potential of their use for Retrograde chronic total occlusion recanalization. Currently, the most widely used method for assessing collateral blood flow is angiography, which, despite its relative simplicity and good knowledge, has following limitations: invasiveness, operator dependence, limited visualization, etc. At the same time, a number of other diagnostic methods can also be used to assess collateral flow. This review article is aimed at a detailed study of modern invasive and non-invasive methods for assessing the development and function of collateral vessels.

Diabetic dyslipidemia impairs coronary collateral formation: An update.

Coronary collateralization is substantially impaired in patients with type 2 diabetes and occlusive coronary artery disease, which leads to aggravated myocardial ischemia and a more dismal prognosis. In a diabetic setting, altered serum lipid profiles and profound glycoxidative modification of lipoprotein particles induce endothelial dysfunction, blunt endothelial progenitor cell response, and severely hamper growth and maturation of collateral vessels. The impact of dyslipidemia and lipid-lowering treatments on coronary collateral formation has become a topic of heightened interest. In this review, we summarized the association of triglyceride-based integrative indexes, hypercholesterolemia, increased Lp(a) with its glycoxidative modification, as well as quantity and quality abnormalities of high-density lipoprotein with impaired collateral formation. We also analyzed the influence of innovative lipid-modifying strategies on coronary collateral development. Therefore, clinical management of diabetic dyslipidemia should take into account of its effect on coronary collateralization in patients with occlusive coronary artery disease.

Early recruitable coronary collaterals preserve miocardial viability in late presentation infarctions.

Previous studies showed conflicting results regarding the contribution of coronary collateral circulation (CCC) to myocardial perfusion and function in the setting of myocardial infarction (MI). In the primary angioplasty era, the role of CCC in these studies may have been influenced by the effect of early reperfusion. The true impact of CCC could be clarified by studying its effect on nonreperfused patients. The aim of our study was to evaluate the effect of CCC on myocardial viability of late presentation MI. Between 2008 and 2019, we included 167 patients with a late presentation MI who had a complete angiographic occlusion in a major coronary artery in which myocardial viability of the culprit territory was assessed. Patients were divided according to the presence of angiographic early recruited CCC (ERCC) (Rentrop 2-3) or poor CCC (PCC) (Rentrop 0-1). A lower left ventricular ejection function (LVEF) at discharge (54.2 ± 9 vs. 47.9 ± 12; <0.01) and a more severe left ventricular wall motion abnormalities in the culprit territory were observed in PCC patients. The presence of ERCC was the main independent predictor of myocardial viability in late presentation MI (hazard ratio, 4.24; 95% confidence interval, 1.68-10.6; P < 0.001). At follow-up, wall motion score increased significantly (2.05 ± 0.16; P = 0.02) in patients with ERCC but not in PCC patients (0.07 ± 0.16; P = 0.4), and LVEF improvement was significantly higher in ERCC than in PCC patients (9.7 ± 2.6 vs. 3.8 ± 4.2; P = 0.02). The presence of ERCC was the main independent predictor of myocardial viability in late presentation MI.

High serum levels of N-epsilon-carboxymethyllysine are associated with poor coronary collateralization in type 2 diabetic patients with chronic total occlusion of coronary artery

BackgroundThe formation of advanced glycation end-products (AGEs) is a crucial risk factor for the pathogenesis of cardiovascular diseases in diabetes. We investigated whether N-epsilon-carboxymethyllysine (CML), a major form of AGEs in vivo, was associated with poor coronary collateral vessel (CCV) formation in patients with type 2 diabetes mellitus (T2DM) and chronic total occlusion (CTO) of coronary artery.MethodsThis study consisted of 242 T2DM patients with coronary angiographically documented CTO. Blood samples were obtained and demographic/clinical characteristics were documented. The coronary collateralization of these patients was defined according to Rentrop or Werner classification. Serum CML levels were evaluated using ELISA assay. Receiver operating characteristic curve and multivariable regression analysis were performed.Results242 patients were categorized into poor CCV group or good CCV group (107 vs. 135 by the Rentrop classification or 193 vs. 49 by the Werner classification, respectively). Serum CML levels were significantly higher in poor CCV group than in good CCV group (110.0 ± 83.35 vs. 62.95 ± 58.83 ng/ml by the Rentrop classification and 94.75 ± 78.29 ng/ml vs. 40.37 ± 28.69 ng/ml by Werner classification, both P < 0.001). Moreover, these CML levels were also significantly different across the Rentrop and Werner classification subgroups (P < 0.001). In multivariable logistic regression, CML levels (P < 0.001) remained independent determinants of poor CCV according to the Rentrop or Werner classification after adjustment of traditional risk factors.ConclusionsThis study suggests that higher serum CML level is associated with poor collateralization in T2DM patients with CTO.

Feasible stenting of a large septal perforator providing a sizeable coronary collaterals

While coronary artery disease involving the septal perforator branches presents similar to diseases of major coronary arteries, management can present a challenge. Owing to their relatively small size, performing interventional procedures is often impractical in terms of selecting appropriate devices. Although larger septal perforator branches have been managed percutaneously, similar to major vessels, long-term sequelae and clinical effectiveness have been indeterminate. We present our experience in managing a patient with a stenosed septal perforator branch and challenging comorbidities.

Endothelial Cell Sprouting in Coronary Collateral Growth

Rationale– Coronary collateral growth is a natural bypass for ischemic heart diseases. It offers tremendous therapeutic benefit, but the process of coronary collateral growth is incompletely understood due to limited preclinical murine models that would enable interrogation of its mechanisms and processes via genetic modification and lineage tracing. Understanding the processes by which coronary collaterals develop can unlock new therapeutic strategies for ischemic heart disease.Objective– To develop a murine model of coronary collateral growth by repetitive ischemia (RI) and investigate the process of coronary collateral growth in adult hearts by lineage tracing.Methods and Results– A murine model of coronary collateral growth was developed using short episodes of repetitive ischemia. Repetitive ischemia resulted in robust collateral growth in adult mouse hearts, validated by high‐resolution micro‐computed tomography. ROSA mT/mG reporter mice with Apln‐CreERT2 transgene were used for lineage tracing of sprouting endothelial cells to determine cellular contributions to coronary collateral growth. Two‐photon and confocal microscopy imaging revealed RI‐induced coronary collateral growth initiated from sprouting Apelin+GFP+endothelial cells. Newly formed capillaries in the collateral‐dependent zone expanded in diameter upon RI stimulation and arterialized with smooth muscle cell recruitment to form mature coronary collateral arteries. Notably, pre‐existing coronary arteries and arterioles were not Apelin+ GFP+, and all Apelin+endothelial cells arose from sprouting capillaries. HIF1α, VEGFR2, CXCR4, MCP‐1, and JAG1 signaling in the collateral‐dependent zone were also upregulated during coronary collateral growth.Conclusions– We developed a murine model of RI‐induced coronary collateral growth, and our data show sprouting EC contribute to coronary collateral growth in adult hearts. Sprouting angiogenesis is shown for the first time to arterialize into mature blood vessels of larger diameter in response to repetitive ischemia in adult hearts.

Correlation of serum vascular endothelial growth factor and cardiovascular risk factors on collateral formation in patients with acute coronary artery syndrome.

Coronary collaterals serve as an alternative source of blood flow in obstructive coronary heart disease. Coronary collateral development is induced by various angiogenic growth factors, including vascular endothelial growth factor-A (VEGF-A). Cardiovascular risk factors strongly associated with coronary artery disease include age, sex, elevated serum cholesterol, disturbed carbohydrate metabolism, and elevated blood pressure. A better understanding of the effects of these cardiovascular risk factors and serum VEGF-A level on collateral recruitment is necessary for a better prognosis in coronary artery diseases and new insight for further therapeutic promotion of coronary collaterals.220 consecutive patients undergoing coronary angiography with a mean age of 61 ± 9.83 were selected for the analysis. Two milliliters of blood were taken from the patients for analysis. The blood serum VEGF concentration was quantified via the ELISA method. Angiograms and other clinical reports were collected. Significant coronary artery disease was diagnosed in those with ≥ 70% of stenosis in at least one of the coronary arteries. The angiographic and clinical data were documented. The collateral grading was done according to the Rentrop Scoring system. The serum vascular endothelial growth factor level was correlated with the collateral score and cardiovascular risk factors like age, sex, type II diabetes, blood pressure, and cholesterol level. An increase in the level of the collateral score was noted with an increase in the level of VEGF in blood serum. A significant association was founded between serum VEGF level and cardiovascular risk factors on collateral formation in patients with diabetes and hypertension.

Increased estimated remnant-like particle cholesterol is associated with impaired coronary collateralization in patients with coronary chronic total occlusions

AimsThis study intends to explore whether, or to what extent, the estimated remnant-like particle cholesterol was associated with coronary collateralization in patients with chronic total occlusion lesions.Methods792 patients with at least one coronary chronic total occlusion lesion were enrolled. Serum level of lipid profiles were determined and the estimated remnant-like particle cholesterol was calculated. The development of coronary collateralization was graded as low (Rentrop score 0–1) or high (Rentrop score 2–3) collateralization according to the Rentrop classification system and then the association between the estimated remnant-like particle cholesterol and collateralization was assessed.Results222 participants were classified into low collateralization group. The estimated remnant-like particle cholesterol level was significantly higher in low collateralization (P < 0.001) and type 2 diabetes mellitus (P = 0.009) group. To further explore the association between the estimated remnant-like particle cholesterol and the development of coronary collateralization, these patients were divided into 3 groups based on the estimated remnant-like particle cholesterol tertiles. The prevalence of low collateralization increased stepwise with the tertile groups (T1 12.5% vs. 27.1% vs. 45.3%, P < 0.001). Multivariate logistic regression analysis showed that the estimated remnant-like particle cholesterol was independently associated with the under-developed collateralization, with an OR and 95%CI of 2.34 (1.46–3.74) and 4.91 (3.01–8.02) in the T2 and T3 group, respectively. The following receiver-operating characteristic analysis indicated that the diagnostic value of estimated remnant-like particle cholesterol for the low collateralization was 0.696, with a cut-off value of 0.485, and its sensitivity was 82.88%. Besides, the addition of the estimated remnant-like particle cholesterol into the baseline model consisting of traditional risk factors could improve the incremental value of the discrimination of impaired collateralization only in overall and type 2 diabetes mellitus populations.ConclusionsThe increased estimated remnant-like particle cholesterol is independently associated with impaired collateralization in patients with coronary chronic total occlusion lesions. Therapies targeting at remnant-like particle cholesterol may be needed in advanced coronary artery disease patients with type 2 diabetes mellitus not suitable for vascular revascularization.