Características y resultados del Registro español de válvula aórtica bicúspide en pediatría (REVAB) / Characteristics and outcomes of the Spanish registry for pediatric patients with bicuspid aortic valve (REVAB)

Introducción y objetivos: La válvula aórtica bicúspide (VAB) es la cardiopatía congénita más frecuente. El objetivo de este estudio es describir las características de los pacientes en edad pediátrica con VAB en un registro poblacional. Métodos: Los datos de los pacientes se obtuvieron del Registro español de válvula aórtica bicúspide (REVAB) en pediatría (menores de 18 años). Para el análisis de datos, se dividió a los pacientes en 2 grupos según sus características: pacientes con VAB solo y pacientes con VAB y cardiopatía congénita concomitantes. Resultados: Se analizó a un total de 1.681 pacientes de 33 hospitales. La mayoría (1.158, 69,6%) eran varones. La morfología de la válvula fue horizontal en el 63,4% (1.012), y puras (tipo 0 Sievers), el 28,4% (469). El 63,7% (1.060) tenían solo VAB y en el 23,4% (390) concurrían lesiones obstructivas del lado izquierdo. Del total, el 8,6% (145) precisó alguna intervención en la válvula aórtica. Conclusiones: Estos datos representan la primera descripción de base poblacional de la presentación clínica y los resultados en los pacientes del REVAB Pediátrico.(AU)

Introduction and objectives: Bicuspid aortic valve (BAV) disorder is the most common congenital heart disease. The aim of this study was to describe the characteristics of 0- to 18-year olds with BAV in a population-based registry. Methods: Data from all pediatric patients were obtained from the Spanish registry for pediatric patients with bicuspid aortic valve (REVAB) (< 18 years). For data analysis, patients with BAV were divided into 2 groups by their features: isolated BAV and BAV with associated congenital heart disease. Results: We included 1681 patients from 33 hospitals. Males accounted for 69.6% (n = 1158). Valve morphology was horizontal in 63.4% (n = 1012) and pure (Sievers type 0) in 28.4% (n=469). Isolated BAV was present in 63.7% (n=1060), and concomitant left-sided obstructive lesions in 23.4% (n=390). Interventions were required in 8.6% (n=145). Conclusion: These data represent the first large, population-based description of the clinical presentations and outcomes of patients enrolled in the Spanish registry for pediatric patients with bicuspid aortic valve.(AU)

Ex Vivo Analysis of an Association of Mechanical Strength of Dilated Ascending Aorta with Tissue Matrix Metalloproteinases and Cytokines.

We analyzed the associations of the mechanical strength of dilated ascending aorta wall (intraoperative samples from 30 patients with non-syndromic aneurysms) with tissue MMPs and the cytokine system. Some samples were stretched to break on an Instron 3343 testing machine and the tensile strength was calculated; others were homogenized and the concentrations of MMP-1, MMP-2, MMP-7, their inhibitors (TIMP-1 and TIMP-2), and pro- and anti-inflammatory cytokines were determined by ELISA. Direct correlations between aortic tensile strength and concentrations of IL-10 (r=0.46), TNFα (r=0.60), and vessel diameter (r=0.67) and an inverse correlation with patient's age (r=-0.59) were revealed. Compensatory mechanisms supporting the strength of the ascending aortic aneurysm are possible. No associations of MMP-1, MMP-7, TIMP-1, and TIMP-2 with tensile strength and aortic diameter were found.

Morphological importance of coronary ostia in equine.

The position of the coronary ostia was investigated in 70 segments of the aorta from young adult crossbred horses. After fixation with a 4% buffered aqueous formaldehyde solution and cautious dissection of the aortic bulb, the morphometric relationships between the coronary ostium and the aortic valvar elements were digitally analysed with the support of Image-Pro Plus® software. In horses, the left coronary ostium was near to the right valvular commissure in all cases (100%) analysed in this study. The left coronary ostium was at the level of the intercommissural line in 57.1% and below it in 42.9%. The right coronary ostium was near to the left valvular commissure in 58.6% (2.14 ± 0.32 cm) and close to the right valvular commissure in 41.4% (2.27 ± 0.40 cm). Concerning the intercommissural line, the right coronary ostia was at its level in 24.3% and below it in 75.7%. Accessory coronary ostia were observed in 8.6% of the specimens. In view of the results, it was possible to assume that the positions of the coronary ostia in equines tend towards a standard morphological disposition. Thus, perfusion of the left coronary artery occurs partly more frequently in ventricular systole and complete perfusion occurs less frequently in ventricular diastole. For the right coronary artery, perfusion is mostly complete in diastole and partially in ventricular systole.

Colapso proximal de una endoprótesis de aorta abdominal: reparación endovascular / Proximal abdominal aortic endograft collapse: endovascular repair

Introducción: el colapso de una endoprótesis en la aorta abdominal constituye una complicación muy poco frecuente, normalmente debida a una mala aposición de la prótesis sobre la pared arterial. La reparación endovascular suele ser la modalidad más utilizada para realinear el dispositivo, aunque no existe una actuación protocolizada. Caso clínico: presentamos el caso de un varón de 67 años diagnosticado de colapso precoz asintomático de una endoprótesis de aorta abdominal con una endofuga de tipo Ia. La tomografía computarizada reveló una invaginación severa del segmento proximal de la endoprótesis, así como un marcado crecimiento del saco aneurismático en el primer mes. Se implantó un stent balón expandible para realinearla de nuevo y reforzar el cuello, con excelente resultado. Discusión: las técnicas endovasculares, como la implantación de un stent, parecen una opción segura para volver a alinear el extremo proximal de una endoprótesis tras su colapso.(AU)

Introduction: in the abdominal aorta, device infolding or collapse is an extremely rare complication, usually related to a poor apposition of the proximal end of the device at the time of intervention. Endovascular repair is the most widely used modality to realign the device. However, there is no consensus on the management. Case report: we present a case of a 67-year-old man with early endograft infolding of the abdominal aorta associated with type Ia endoleak. The patient was asymptomatic, without ischemic limb complications. Computed tomography angiography reveled severe invagination of the proximal end of the stent graft, and marked growth of the aneurysm sac during the first month of follow-up. We decided to start by expanding the proximal sealing stent with balloon angioplasty. Finally, we used a balloon-expandable stent to realign and reinforce the proximal end of the endograft. This endovascular technique may be an effective endovascular adjunct to treat abdominal endograft collapses. Discussion: endovascular repair, as stent implantation, may be a secure option to realign the proximal end of the endoprosthesis after its collapse.(AU)

The Sinotubular Junction-to-Aortic Annulus Ratio as a Determinant of Supravalvar Aortic Stenosis Severity.

Supravalvar aortic stenosis (SVAS) severity guides management, including decisions for surgery. Physiologic and technical factors limit the determination of SVAS severity by Doppler echocardiography and cardiac catheterization in Williams syndrome (WS). We hypothesized SVAS severity could be determined by the sinotubular junction-to-aortic annulus ratio (STJ:An). We reviewed all preintervention echocardiograms in patients with WS with SVAS cared for at our center. We measured STJ, An, peak and mean Doppler gradients, and calculated STJ:An. We created 2 mean gradient prediction models. Model 1 used the simplified Bernoulli's equation, and model 2 used computational fluid dynamics (CFD). We compared STJ:An to Doppler-derived and CFD gradients. We reviewed catheterization gradients and the waveforms and analyzed gradient variability. We analyzed 168 echocardiograms in 54 children (58% male, median age at scan 1.2 years, interquartile range [IQR] 0.5 to 3.6, median echocardiograms 2, IQR 1 to 4). Median SVAS peak Doppler gradient was 24 mm Hg (IQR 14 to 46.5). Median SVAS mean Doppler gradient was 11 mm Hg (IQR 6 to 21). Median STJ:An was 0.76 (IQR 0.63 to 0.84). Model 1 underpredicted clinical gradients. Model 2 correlated well with STJ:An through all severity ranges and demonstrated increased pressure recovery distance with decreased STJ:An. The median potential variability in catheterization-derived gradients in a given patient was 14.5 mm Hg (IQR 7.5 to 19.3). SVAS severity in WS can be accurately assessed using STJ:An. CFD predicts clinical data well through all SVAS severity levels. STJ:An is independent of physiologic state and has fewer technical limitations than Doppler echocardiography and catheterization. STJ:An could augment traditional methods in guiding surgical management decisions.

Quantitative not qualitative histology differentiates aneurysmal from nondilated ascending aortas and reveals a net gain of medial components.

Medial degeneration is a common histopathological finding in aortopathy and is considered a mechanism for dilatation. We investigated if medial degeneration is specific for sporadic thoracic aortic aneurysms versus nondilated aortas. Specimens were graded by pathologists, blinded to the clinical diagnosis, according to consensus histopathological criteria. The extent of medial degeneration by qualitative (semi-quantitative) assessment was not specific for aneurysmal compared to nondilated aortas. In contrast, blinded quantitative assessment of elastin amount and medial cell number distinguished aortic aneurysms and referent specimens, albeit with marked overlap in results. Specifically, the medial fraction of elastin decreased from dilution rather than loss of protein as cross-sectional amount was maintained while the cross-sectional number, though not density, of smooth muscle cells increased in proportion to expansion of the media. Furthermore, elastic lamellae did not thin and interlamellar distance did not diminish as expected for lumen dilatation, implying a net gain of lamellar elastin and intralamellar cells or extracellular matrix during aneurysmal wall remodeling. These findings support the concepts that: (1) medial degeneration need not induce aortic aneurysms, (2) adaptive responses to altered mechanical stresses increase medial tissue, and (3) greater turnover, not loss, of mural cells and extracellular matrix associates with aortic dilatation.

Maternal Dietary Carbohydrate Intake and Newborn Aortic Wall Thickness.

Evidence from animal models indicates that maternal diet during pregnancy affects offspring cardiometabolic health. Improving carbohydrate quality during high-risk pregnancies reduces aortic intima-medial thickness; a marker for early atherosclerosis; in the infant offspring. We sought to determine whether maternal carbohydrate quantity and quality are associated with newborn aortic intima-medial thickness in healthy pregnancies. Maternal diet throughout pregnancy was evaluated in 139 mother-child dyads using a validated food frequency questionnaire. Carbohydrate intake was expressed as quantity (% total energy), quality (fibre, glycaemic index), and glycaemic burden (glycaemic load). Aortic intima-medial thickness was measured by high-frequency ultrasound of the neonatal abdominal aorta. Neither quantity nor quality of maternal carbohydrate intake during pregnancy was associated with meaningful differences in offspring maximum aortic intima-medial thickness with the exception of fibre intake in women with overweight or obesity which was inversely associated (-8 µm [95% CI -14, -1] per g fibre, p = 0.04). In healthy pregnancy, the quantity and quality of maternal carbohydrate intake is likely not a meaningful modifiable lifestyle factor for influencing offspring vascular health. The effect of carbohydrate quality may only be evident in high-risk pregnancies, consistent with previous findings. These findings may be confirmed in prospective dietary trials in pregnancy.

Maternal Intake of Flaxseed During Lactation and Exercise Training Protect Against Salt Overload-Induced Aortic Remodeling in Adult Offspring

Abstract Background High dietary sodium intake can induce endothelial stiffness even without changes in blood pressure. Objectives To evaluate the effects of exercise training and chronic intake of sodium chloride solution on aortic morphology of male offspring of rat dams who consumed flaxseed during lactation. Methods Female rats were fed with a control diet or a flaxseed diet during lactation. At weaning, two male offspring of each rat dam were allocated into eight groups for 180 days: four groups received a control diet e four received a flaxseed diet, with /without exercise and with/without NaCl solution supply. Aorta was collected for histomorphometric analysis. The one-way analysis of variance was used and P value < 0.05 was considered statistically significant. Results The chronic use of 1% NaCl solution led to changes in aortic histoarchitecture in the control group: increase in aortic intima-media thickness (10,4%, p<0.0001) and reduced number of elastic lamellae (-8,1%, p<0.0001). Groups of offspring of mother that consumed flaxseed during lactation, the chronic use of 1% NaCl alone did not lead to an increase in the aortic intima-media thickness. Exercise training of adult offspring increased aortic intima-media thickness (13.3%, p<0.0001), with preservation of elastic components and aortic flexibility. Conclusion Chronic salt overload caused adverse effects on the aorta of rats, and maternal consumption of the flaxseed diet during lactation protected against aortic remodeling. Int J Cardiovasc Sci. 2020; [online].ahead print, PP.0-0

Aortic root measurement on CT: linear dimensions, aortic root area and comparison with echocardiography. A retrospective cross sectional study.

OBJECTIVE: We sought to assess the different CT aortic root measurements and determine their relationship to transthoracic echocardiography (TTE). METHODS: TTE and ECG-gated CT images were reviewed from 70 consecutive patients (mean age 54 ± 18 years; 67% male) with tricuspid aortic roots (trileaflet aortic valves) between Nov 2009 and Dec 2013. Three CT planes (coronal, short axis en face and three-chamber) were used for measurement of nine linear dimensions. TTE aortic root dimension was measured as per guidelines from the parasternal long axis view. RESULTS: All CT short axis measurements of the aortic root had excellent reproducibility (intraclass correlation coefficient, ICC 0.96-0.99), while coronal and three-chamber planes had lower reproducibility with ICC 0.90 (95% CI 0.84-0.94) and ICC 0.92 (0.87-0.95) respectively. CT coronal and short axis maximal dimensions were systematically larger than TTE (mean 2 mm larger, p < 0.001), while CT cusp to commissure measurements were systematically smaller (CT RCC-comm mean 2 mm smaller than TTE, p < 0.001). All CT short axis measurements had excellent correlation with aortic root area with CT short axis maximal dimension marginally better than the rest (Pearson's R 0.97). CONCLUSION: Systematic differences exist between CT and TTE dependent on the CT plane of measurement. All CT short axis measurements of the aortic root had excellent reproducibility and correlation with aortic root area with maximal dimension appearing marginally better than the rest. Our findings highlight the importance of specifying the chosen plane of aortic root measurement on CT. ADVANCES IN KNOWLEDGE: Systematic differences in aortic root dimension exist between TTE and the various CT measurement planes. CT coronal and short axis maximal dimensions were systematically larger than TTE, while CT cusp to commissure measurements were smaller. CT readers should indicate the plane of measurement and the specific linear dimension to avoid ambiguity in follow-up and comparison.

In vitro evaluation of a new aortic valved conduit.

BACKGROUND: This study examined whether the presence of a sinus of Valsalva equivalent in the KONECT RESILIA aortic valved conduit (Edwards Lifesciences, Irvine, Calif) improves valve hemodynamics, kinematics, and performance. METHODS: A 28-mm KONECT RESILIA aortic valved conduit was used to create an in vitro flow test model, and the same aortic valved conduit model without a sinus section was used as a control. Particle image velocimetry and hydrodynamic characterization experiments were conducted in the vicinity of the valves in a validated left-heart simulator at 3 cardiac output levels. In addition, leaflet kinematics of the valves were determined through en face high-speed imaging. RESULTS: The KONECT RESILIA aortic valved conduit model exhibited lower mean and peak transvalvular pressure gradients than the control model at all 3 cardiac outputs. In addition, its leaflets opened more fully than did those of the valved conduit without the sinuses, yielding greater effective and geometric orifice areas. It was found that the presence of the sinuses not only facilitated the development of larger and more stable vortices at the initial stages of the cardiac cycle but also helped to maintain these vortices during the late stages of the cardiac cycle, leading to smoother valve closure. CONCLUSIONS: The KONECT RESILIA aortic valved conduit reproduces the bulged section of the aortic root corresponding to the sinuses of Valsalva. With this Valsalva-type conduit, larger orifice areas were observed, improving valve hemodynamics that may enhance performance.

Effect of conventional and rapid-deployment aortic valve replacement on the distance from the aortic annulus to coronary arteries.

OBJECTIVES: This study aimed to compare the effect of surgical aortic valve replacement (SAVR) on coronary height in patients undergoing SAVR with rapid-deployment or SAVR with several standard sutured bioprostheses. This study may identify patients at higher risk of coronary obstruction during valve-in-valve procedures. METHODS: We analysed 112 patients [mean age 71 (9 SD) years] who underwent SAVR with either a rapid-deployment aortic bioprosthesis (EDWARDS INTUITY Elite Valve) or other standard sutured biological valves. The coronary heights were assessed by computed tomography scan with the Philips 3D HeartNavigator system. RESULTS: Two groups of patients were analysed: 51 (45.5%) patients implanted with an RD-AVR, which is a supra-annular valve that requires 3 anchoring sutures without the use of pledgets, and 61 (54.5%) patients implanted with a conventional supra-annular sutured bioprosthesis. The mean right and left coronary artery-to-annulus (RCAA and LCAA) heights at baseline were 16.9 (4.6 SD) and 14.2 (4.0 SD) mm in the standard sutured group and 16.3 (3.5 SD) and 12.8 (2.9 SD) mm in the RD-AVR group, respectively; a significantly shorter distance was observed for the left coronary artery in the rapid-deployment group (P = 0.420 for RCAA height and P = 0.044 for LCAA). Postoperatively, the mean RCAA and LCAA heights were significantly decreased in both groups compared to baseline. A mean of 11.5 (4.8 SD) mm for the RCAA and 7.9 (4.3 SD) mm for the LCAA in the standard sutured group as well as 14.4 (3.9 SD) mm for the RCAA and 9.0 (3.1 SD) mm for the LCAA in the RD-AVR group were observed (P < 0.001 for RCAA and LCAA in both the sutured and rapid-deployment groups). Despite the significant difference in the mean distance from the left coronary artery to annulus between the groups at baseline, the postoperative mean distance of the LCAA to the sewing ring was still higher in the RD-AVR group. CONCLUSIONS: A significantly shorter coronary artery-to-aortic annulus distance for both the right and left main coronary arteries was observed after AVR with different conventional sutured supra-annular bioprostheses compared to AVR with rapid-deployment valves. These findings might be relevant for bioprosthesis selection, especially for young patients.

Reproducibility of Aorta Segmentation on 4D Flow MRI in Healthy Volunteers.

BACKGROUND: Hemodynamic aorta parameters can be derived from 4D flow MRI, but this requires lumen segmentation. In both commercially available and research 4D flow MRI software tools, lumen segmentation is mostly (semi-)automatically performed and subsequently manually improved by an observer. Since the segmentation variability, together with 4D flow MRI data and image processing algorithms, will contribute to the reproducibility of patient-specific flow properties, the observer's lumen segmentation reproducibility and repeatability needs to be assessed. PURPOSE: To determine the interexamination, interobserver reproducibility, and intraobserver repeatability of aortic lumen segmentation on 4D flow MRI. STUDY TYPE: Prospective and retrospective. POPULATION: A healthy volunteer cohort of 10 subjects who underwent 4D flow MRI twice. Also, a clinical cohort of six subjects who underwent 4D flow MRI once. FIELD STRENGTH/SEQUENCE: 3T; time-resolved three-directional and 3D velocity-encoded sequence (4D flow MRI). ASSESSMENT: The thoracic aorta was segmented on the 4D flow MRI in five systolic phases. By positioning six planes perpendicular to a segmentation's centerline, the aorta was divided into five segments. The volume, surface area, centerline length, maximal diameter, and curvature radius were determined for each segment. STATISTICAL TESTS: To assess the reproducibility, the coefficient of variation (COV), Pearson correlation coefficient (r), and intraclass correlation coefficient (ICC) were calculated. RESULTS: The interexamination and interobserver reproducibility and intraobserver repeatability were comparable for each parameter. For both cohorts there was very good reproducibility and repeatability for volume, surface area, and centerline length (COV = 10-32%, r = 0.54-0.95 and ICC = 0.65-0.99), excellent reproducibility and repeatability for maximal diameter (COV = 3-11%, r = 0.94-0.99, ICC = 0.94-0.99), and good reproducibility and repeatability for curvature radius (COV = 25-62%, r = 0.73-0.95, ICC = 0.84-0.97). DATA CONCLUSION: This study demonstrated no major reproducibility and repeatability limitations for 4D flow MRI aortic lumen segmentation. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY STAGE: 2.

Morphological and Histopathological Study of Autopsied Patients with Atherosclerosis and HIV.

BACKGROUND: Chronic infection by HIV evolves with a vascular inflammatory action causing endothelial dysfunction. The action of the virus, as well as the side effects of antiretroviral drugs, contribute to the progression of cardiovascular diseases. The present study aimed to evaluate the percentage of collagen fibers and the density of mast cells, chymase and tryptase, in aortas of patients with and without HIV, and also patients with and without atherosclerosis. METHODS: Aortic fragments were obtained from autopsied patients aged 22-69 years and selected regardless of the cause of death or underlying disease. The samples were divided into four groups, (1) Group with HIV and with atherosclerosis; (2) Group with HIV and without atherosclerosis; (3) Group without HIV and with atherosclerosis; (4) Group without HIV and without atherosclerosis (Control). The percentage of collagen fibers was analyzed in the intima-media layer and the density of mast cells was analyzed in all aortic layers. Graphpad Prism 5.0® software was used for statistical analysis. RESULTS: There were more collagen fibers in HIV patients, with or without atherosclerosis. The group with HIV and atherosclerosis presented a higher density of chymase and tryptase mast cells. The correlation between collagen fibers and age was negative in the non-HIV group and with atherosclerosis. CONCLUSION: The inflammatory process resulting from HIV infection may be relevant in the alteration of aortic collagen fibers and in triggering or accelerating atherosclerosis. The study is important because HIV patients have increased risks for the development of cardiovascular diseases, and follow-up is necessary to prevent such diseases.

CT-Derived Pulmonary Artery Diameters to Preselect for Echocardiography in COPD Patients Eligible for Bronchoscopic Treatments.

BACKGROUND: Currently, patients with COPD who are evaluated for bronchoscopic treatments are routinely screened for pulmonary hypertension (PH) and systolic left ventricle dysfunction by echocardiography. OBJECTIVES: We evaluated the prevalence of PH and systolic left ventricle dysfunction in this patient group and investigated if the previously proposed CT-derived pulmonary artery to aorta (PA:A) ratio >1 and PA diameter measurements can be used as alternative screening tools for PH. METHODS: Two hundred fifty-five patients were included in this retrospective analysis (FEV1 25%pred, RV 237%pred). All patients received transthoracic echocardiography and chest CT scans on which diameters of the aorta and pulmonary artery were measured at the bifurcation and proximal to the bifurcation. RESULTS: Following echocardiography, 3 patients (1.2%) had PH and 1 (0.4%) had systolic left ventricle dysfunction. Using a PA:A ratio >1, only 10.3% of the patients with a right ventricular systolic pressure (RVSP) ≥35 mm Hg were detected and none of the patients with an RVSP >50 mm Hg were detected. Patients with an RVSP ≥35 mm Hg had significantly higher PA diameters (29.5 vs. 27.5 mm; p = 0.02) but no significantly different PA:A ratios. All patients with an RVSP >50 mm Hg had PA diameters >30 mm. CONCLUSIONS: The prevalence of PH and systolic left ventricle dysfunction is low in this preselected cohort of patients with severe COPD. In this population, a PA:A ratio >1 is not a useful cardiac screening tool for PH. A PA diameter >30 mm could substitute for routinely performed echocardiography in the screening for PH in this patient group.

Measurement of aortic root dimensions by transesophageal echocardiography in adult patients undergoing cardiac surgery.

Background: Normal aortic root dimensions were established from studies from Western countries. As the body size is significantly associated with the aortic root dimensions, Thai populations may have smaller aortic root diameters. Aims: To elucidate the aortic root dimensions using transesophageal echocardiography (TEE) in adult patients undergoing cardiac surgery. Settings and Design: A retrospective cohort study including 150 patients aged >18 years undergoing cardiac surgery. Materials and Methods: Aortic root dimensions (annulus, sinus of Valsalva, sinotubular junction (STJ), and proximal ascending aorta) were measured using two-dimensional TEE. Patients with aortic-root related pathology were excluded. Results: Men constituted 60% of the study population; the mean age was 61.9 ± 12.6 years, and mean body surface area (BSA) was 1.7 ± 0.2 m2. The absolute dimensions for the annulus, sinus of Valsalva, STJ, and proximal ascending aorta were 22.3 ± 3.4, 32.6 ± 3.9, 26.4 ± 3.3, and 29.3 ± 3.1 mm, respectively, in men (12.9 ± 1.6, 18.8 ± 2.6, 15.2 ± 2.1, and 17.9 ± 2.7 mm, respectively, after adjusting for BSA) and 20.3 ± 2.2, 29.8 ± 3.6, 23.8 ± 2.6, and 27.1 ± 3.1 mm, respectively, in women (13.5 ± 2.0, 19.8 ± 2.3, 15.8 ± 2.5, and 17.0 ± 2.1 mm, respectively, after adjusting for BSA). The absolute aortic root diameters were significantly greater in men at all levels (P < 0.001). The BSA-adjusted diameters were similar for both sexes at the annulus (P = 0.076) and STJ (P = 0.076), except for the sinus of Valsalva (P = 0.010) and proximal ascending aorta (P = 0.006). Conclusion: This study reports reference values of aortic root dimensions by TEE. The body size should be considered when comparing the aortic root dimensions of Thai populations with the standard normal values.

A nonlinear rotation-free shell formulation with prestressing for vascular biomechanics.

We implement a nonlinear rotation-free shell formulation capable of handling large deformations for applications in vascular biomechanics. The formulation employs a previously reported shell element that calculates both the membrane and bending behavior via displacement degrees of freedom for a triangular element. The thickness stretch is statically condensed to enforce vessel wall incompressibility via a plane stress condition. Consequently, the formulation allows incorporation of appropriate 3D constitutive material models. We also incorporate external tissue support conditions to model the effect of surrounding tissue. We present theoretical and variational details of the formulation and verify our implementation against axisymmetric results and literature data. We also adapt a previously reported prestress methodology to identify the unloaded configuration corresponding to the medically imaged in vivo vessel geometry. We verify the prestress methodology in an idealized bifurcation model and demonstrate the significance of including prestress. Lastly, we demonstrate the robustness of our formulation via its application to mouse-specific models of arterial mechanics using an experimentally informed four-fiber constitutive model.

Low correlation between biometric parameters, cardiovascular risk factors and aortic dimensions by computed tomography coronary angiography.

To analyze the relationship between aortic measures and biometric parameters in a large cohort of consecutive patients undergoing computed tomography coronary angiography.1170 patients (717 men/453 women) performing computed tomography coronary angiography for coronary evaluation were retrospectively evaluated. Aortic diameters and areas were measured at reproducible anatomic landmarks, perpendicular to the axis of vessel, at the level of the aortic root (AoR), the sinotubular junction (STJ), and the tubular ascending aorta (TAo). Biometric parameters and cardiovascular risk factors were recorded.The average values of AoR, STJ, and TAo were 35.63 ±â€Š5.00 mm, 30.56 ±â€Š4.82 mm, 35.07 ±â€Š5.84 mm. Hypertension was significantly associated with aortic dimensions.Aortic measures were significantly different between men and women (37.56 ±â€Š4.77 mm vs 32.58 ±â€Š3.68 mm for AoR, 31.88 ±â€Š4.84 mm vs 28.47 ±â€Š3.98 mm for STJ and 35.93 ±â€Š5.86 mm vs 33.70 ±â€Š5.54 mm for TAo) (P < .001) and linearly increased with age. Low Spearman correlation coefficients were found and the correlation of TAo diameters with age displayed the highest values (ρ = 0.372 for male and ρ = 0.373 for female, P < .001). Multiple linear regression analysis models were compared by R. The best model used body surface area (BSA) and age as independent variables and TAo diameter as dependent variable (R = 0.29 for AoR; R = 0.21 for STJ, and R = 0.20 for TAo).In conclusion, in our population low correlation between aortic dimensions and biometric parameters highlights the difficulty of identifying normal ranges, as well as issues related to normalization using conventional biometric parameters.