The Impact of the Right Coronary Artery Geometric Parameters on Hemodynamic Performance.

PURPOSE: Coronary artery geometry can have a significant impact in the hemodynamic behavior of coronary blood flow, influencing atherosclerotic plaque formation. The present work focuses on, through a statistical study, the connection between several geometric parameters of the right coronary artery-ostium cross-sectional area, angles between the common trunk and the side-branches, tortuosity, curvature and cross-sectional area in each side-branch-and their influence on hemodynamic descriptors. Parameters such as low wall shear stress and local disturbed flow, which are associated with atherosclerosis formation, were analysed. METHODS: Computed tomography images of ten healthy individuals were selected to reconstruct in vivo three-dimensional models of right coronary arteries. Blood flow was simulated through a compliant model with realistic boundary conditions. Calculated hemodynamic descriptors values were correlated with the geometric parameters using the Pearson correlation coefficient (r) and the p value. RESULTS: The strongest correlations were found in the middle and distal segments of the right coronary artery. A decrease in the ostium area promotes a decrease in the WSS magnitude from the proximal to the distal segment (r = 0.82). Very strong correlations (r > 0.90) were achieved between geometric parameters (cross-sectional area, angle, tortuosity) of the right-ventricular branch and the wall shear stress magnitude in the middle and distal segments. CONCLUSIONS: Low values of tortuosity, smaller cross-sectional area and higher angle of the right-ventricular branch leads to a hemodynamic behavior more propitious to atherosclerosis formation, within the study cases. The right-ventricular branch seems to have the highest influence in the hemodynamic behavior of the right coronary artery.

Correlation between geometric parameters of the left coronary artery and hemodynamic descriptors of atherosclerosis: FSI and statistical study.

The hemodynamics conditioned by coronary geometry may play an important role in the creation of a pro-atherogenic environment in specific locations of the coronary tree. The aim of this study is to identify how several geometric parameters of the left coronary artery - cross-section areas, proximal left anterior descending artery length, angles between the branches and the septum, curvature and tortuosity - can be related with hemodynamic descriptors, using a computational fluid-structure interaction method. It is widely accepted that the hemodynamic indicators play an important role in identifying possible pro-atherogenic locations. A statistical study, using Pearson correlation coefficient and P value, was performed for a population study of 8 normal human left coronary arteries presenting right-dominant circulation. Within the study cases, arteries with high caliber (r = 0.88), high angles LMS-LAD (r = 0.49), LAD-LCx (r = 0.57) and LAD-Septum (r = 0.52), and high tortuosity LMS-LCx (r = 0.63) were correlated with a hemodynamic behavior propitious to plaque formation in the left anterior descending artery. In contrast, high proximal left anterior descending artery length (r = -0.41), high angle LMS-LCx (r = -0.59), high tortuosity LMS-LAD (r = -0.56) and LAD-LCx (r = -0.55) and high curvature of LMS (r = -0.60) and LCx (r = -0.56) can lead to non-favorable hemodynamic conditions for atheroma formation. Graphical abstract.

Frailty Syndrome: Visceral Adipose Tissue and Frailty in Patients with Symptomatic Severe Aortic Stenosis.

BACKGROUND/OBJECTIVES: In patients with severe aortic stenosis (AS), frailty is a clinically relevant measure of increased vulnerability that should be included in the preoperative risk assessment. Bioelectrical impedance analysis (BIA) derived phase angle (PA) reflects cell membrane integrity and function. Few studies are available on the relative contribution of adiposity distribution on frailty, and about the influences of frailty and visceral obesity in PA value. Therefore, we aimed to evaluate associations among frailty, visceral fat depots and PA in patients with symptomatic severe AS. METHODS: In a cohort of patients with symptomatic severe AS and preserved ejection fraction, we examined the associations between frailty, visceral fat depots and bioelectrical impedance analysis (BIA) derived phase angle (PA); and between visceral fat and PA. Frailty was defined according the Fried et al. scale criteria and the body fat distribution was determined by multidetector computed tomography and by BIA. RESULTS: Of the fifty-five included patients, 26 were frail (47%). Adjusting for age and gender, frailty was associated with indexed epicardial adipose tissue volume (EATVi) (the odds of frailty increased 4.1-fold per additional 100 cm3/m2 of EAT [95% confidence interval (CI) of 1.03 to 16.40, p=0.04] and with PA (OR of 0.50, 95% CI, 0.26 to 0.97, p=0.04), but not with body mass index (BMI), waist circumference (WC), indexed total, visceral and subcutaneous abdominal fat areas (TAFAi, VAFAi and SAFAi) nor with indexed mediastinal adipose tissue volume (MATVi). In an age and gender adjusted linear model, PA was inversely correlated with EATVi (ß=-0.008, 95% CI, -0.016 to -0.001, p=0.03), but not with BMI, WC, nor with MATVi, VAFAi, SAFAi and TAFAi. CONCLUSIONS: In patients with symptomatic severe AS, EATVi is associated with frailty, independently of age and gender, but not with MAFVi or VAFAi. Moreover, frailty and EATVi are associated with impaired cell membrane integrity and function assessed by PA.

Epicardial adipose tissue and coronary artery calcification in psoriasis patients.

BACKGROUND: Psoriasis is a chronic, immune-mediated disease associated with several cardio-metabolic comorbidities, accelerated atherosclerosis and cardiovascular disease (CVD). Other causes beyond systemic inflammation and traditional cardiovascular risk factors (CVRF) may be implicated in the increased risk of CVD observed in these patients. Epicardial adipose tissue (EAT), a type of visceral adipose tissue surrounding the heart and coronary vessels has been implicated in the development of coronary artery disease, by endocrine mechanisms, but particularly by local inflammation. OBJECTIVE: To compare EAT volumes in psoriasis patients and controls using multidetector computed tomography (MDCT) and to analyse if eventual differences were independent from abdominal visceral adiposity; to determine, within psoriasis patients, its relation with subclinical atherosclerosis and other markers of cardiometabolic risk. METHODS: One hundred patients with severe psoriasis, without CVD underwent MDCT, with EAT and abdominal visceral fat (AVF) assessment and coronary artery calcification (CAC) quantification and were compared with 202 control patients. RESULTS: EAT volume was increased in psoriasis patients compared to control subjects, independently from age, sex and AVF, being, on average, 15.2 ± 4.41 mL higher (95% CI: 6.5-26.0, P = 0.001) than in controls. Moreover, psoriasis patients had a statistically significant higher risk of having subclinical atherosclerosis (OR 2.52, 95% CI: 1.23-5.16) than controls, after adjusting for traditional CVRF. Within psoriasis patients EAT volume was associated with subclinical atherosclerosis, independently of age, sex, psoriasis duration, classical CVRF and AVF. CONCLUSION: This study showed that psoriasis was associated with increased EAT volume independently of visceral abdominal fat and with subclinical atherosclerosis. Within psoriasis patients EAT volume was independently associated with CAC. EAT may be another important contributor to the higher cardiovascular risk observed in psoriasis.

Epicardial adipose tissue is an independent predictor of coronary atherosclerotic burden.

INTRODUCTION: Epicardial adipose tissue (EAT) may play an active role in the development of coronary artery disease (CAD). The aim of this work was to study the relations between EAT, abdominal visceral fat (AVF), and coronary atherosclerotic burden as assessed by multislice computed tomography (MSCT). POPULATION AND METHODS: Two hundred fifteen patients without known CAD referred to 64-SCT during a 6-months period were included. All patients underwent a standardized protocol including quantification of AVF, EAT, coronary artery calcification (CAC), and coronary angiography by MSCT. RESULTS: Two hundred fifteen patients, with mean age of 58 ± 11 years, in which 61% were males, with mean body mass index (BMI) of 28 ± 4 kg/m(2) were included. EAT volume was directly associated with male sex, age, BMI, abdominal circumference, AVF, number of coronary segments with atherosclerotic plaques (p<0.01 for all), number of segments with significant stenoses, and presence of metabolic syndrome components (p<0.05). CAC increased by 14.7% per additional 10 ml of EAT volume. Adjusting for age, gender, and AVF changed this increase to 7.5%. After adjusting for all considered confounders, there was still an independent association, with a CAC increase of 3.7% per additional 10 ml of EAT. A significant interaction was found between EAT volume and gender and between EAT volume and obesity: an increase of EAT was associated with an increase of additional 8% of CAC in men, and additional increase of 5% in non-obese individuals (p<0.001 for both). CONCLUSION: EAT volume positively relates to coronary atherosclerotic burden, as assessed by CAC; this correlation was shown to be independent of AVF.

Prevention of unfavorable scars using early pulse dye laser treatments: a preliminary report.

Hypertrophic scarring occurs frequently in the trunk and extremities, and sporadically in other areas even under favorable circumstances. Unfortunately, the existing methods of scar manipulation have not been effective in preventing these unfavorable scars. Established hypertrophic scars have been treated by Anderson and Parrish, Alster, and others using the 585-nm pulse dye laser. The current study is the first report of prevention of hypertrophic scarring using the 585-nm pulse dye laser in a large group of elective and traumatic incisions. Treatment within the first few weeks resulted in faster resolution of scar stiffness and erythema, and less frequent development of hypertrophic scarring. An unexpected finding was the substantial improvement in the quality of scarring in all areas of the body, attributed to the excellent color match of the treated scars. These observations suggest that early pulse dye laser treatments can change fundamentally the physiology of wound healing if applied in the early phases. This report provides the first clinical correlation between prophylactic laser reduction of scar microcirculation and prevention of excessive scar formation.