Publications associées à Aorte

Compliant vascular grafts and methods of use

Compliant vascular grafts for implantation in the vasculature are provided. The compliant vascular grafts are designed to expand longitudinally and radially within a blood vessel, such as an artery, and is expected to be particularly well suited for treati ...

2024

Novel theory and potential applications of central diastolic pressure decay time constant

Nikolaos Stergiopoulos, Georgios Rovas, Sokratis Anagnostopoulos, Vasiliki Bikia, Patrick Segers

Central aortic diastolic pressure decay time constant ( ) is according to the two-element Windkessel model equal to the product of total peripheral resistance (R) times total arterial compliance (C ). As such, it is related to arterial stiffness, which has ...

2024

Hemodynamic effects of a dielectric elastomer augmented aorta on aortic wave intensity: An in-vivo study

Yves Perriard, Yoan René Cyrille Civet, Thomas Guillaume Martinez, Francesco Clavica, Armando Matthieu Walter, Silje Ekroll Jahren, Lorenzo Ferrari

Dielectric elastomer actuator augmented aorta (DEA) represents a novel approach with high potential for assisting a failing heart. The soft tubular device replaces a section of the aorta and increases its diameter when activated. The hemodynamic interactio ...

2023

Compliance-matching vascular grafts with personalization potential

Georgios Rovas

Aortic diseases are characterized by dire prognosis and inadequate diagnosis, owing to their insidious yet lethal nature. Aortopathies, namely aortic aneurysms and dissections, along with certain congenital diseases, might necessitate surgical replacement ...

EPFL2023

Modulation of Pulsatile Left Ventricular Afterload by Renal Denervation in Heart Failure With Preserved Ejection Fraction

Nikolaos Stergiopoulos, Stamatia Zoi Pagoulatou

Background:Arterial stiffening contributes to hemodynamic derangements in heart failure with preserved ejection fraction (HFpEF). We sought to investigate the impact of renal denervation on pulsatile left ventricular loading in patients with HFpEF and hype ...

Lippincott Williams & Wilkins2023

A novel soft cardiac assist device based on a dielectric elastomer augmented aorta: An in vivo study

Yves Perriard, Yoan René Cyrille Civet, Thomas Guillaume Martinez, Francesco Clavica, Armando Matthieu Walter, Jonathan André Jean-Marie Chavanne, Silje Ekroll Jahren, Lorenzo Ferrari

Although heart transplant is the preferred solution for patients suffering from heart failures, cardiac assist devices remain key substitute therapies. Among them, aortic augmentation using dielectric elastomer actuators (DEAs) might be an alternative tech ...

2022

Arterial Wave Reflection and Aortic Valve Stenosis: Diagnostic Challenges and Prognostic Significance

Nikolaos Stergiopoulos, Georgios Rovas, Vasiliki Bikia, Stamatia Zoi Pagoulatou

IntroductionArterial wave reflection is an important component of the left ventricular afterload, affecting both pressure and flow to the aorta. The aim of the present study was to evaluate the impact of wave reflection on transvalvular pressure gradients ...

FRONTIERS MEDIA SA2022

Feasibility of a Dielectric Elastomer Augmented Aorta

Yves Perriard, Yoan René Cyrille Civet, Jonathan André Jean-Marie Chavanne, Francesco Clavica, Morgan Almanza, David Moser

Although heart transplantation is a gold standard for severe heart failure, there is a need for alternative effective therapies. A dielectric‐elastomer aorta is used to augment the physiological role of the aorta in the human circulatory system. To this en ...

2021

Acute and Long-Term Effects of Aortic Compliance Decrease on Central Hemodynamics: A Modeling Analysis

Nikolaos Stergiopoulos, Georgios Rovas, Vasiliki Bikia, Stamatia Zoi Pagoulatou

Aortic compliance is an important determinant of cardiac afterload and a contributor to cardiovascular morbidity. In the present study, we sought to provide in silico insights into the acute as well as long-term effects of aortic compliance decrease on cen ...

FRONTIERS MEDIA SA2021

Distinct types of plexiform lesions identified by synchrotron-based phase-contrast micro-CT

Goran Lovric

In pulmonary arterial hypertension, plexiform lesions are associated with severe arterial obstruction and right ventricular failure. Exploring their structure and position is crucial for understanding the interplay between hemodynamics and vascular remodel ...

AMER PHYSIOLOGICAL SOC2021

The effect of the elongation of the proximal aorta on the estimation of the aortic wall distensibility

Nikolaos Stergiopoulos, Georgios Rovas, Bram Trachet, Vasiliki Bikia, Stamatia Zoi Pagoulatou, Mauro Ferraro

The compliance of the proximal aortic wall is a major determinant of cardiac afterload. Aortic compliance is often estimated based on cross-sectional area changes over the pulse pressure, under the assumption of a negligible longitudinal stretch during the ...

2021

Hemodynamics of ageing, ventricular-arterial coupling and noninvasive assessment of key hemodynamical and cardiac quantities

Stamatia Zoi Pagoulatou

Ageing is a natural process that affects both the anatomical and functional properties of the cardiovascular system and alters the coupling characteristics between the heart and the aorta. These alterations may predispose the cardiovascular system in the d ...

EPFL2020

Cardiotrophin-1 Deficiency Abrogates Atherosclerosis Progression

Nikolaos Stergiopoulos, Rodrigo Araujo Fraga Da Silva

Cardiotrophin-1 (CT-1) is associated with cardiovascular (CV) diseases. We investigated the effect of CT-1 deficiency in the development and progression of atherosclerosis in double knockout Apoe(-/-)ct-1(-/-) mice. Apoe(-/-) C57Bl/6 or Apoe(-/-)ct-1(-/-) ...

Nature Research2020

Long noncoding RNA SNHG12 integrates a DNA-PK-mediated DNA damage response and vascular senescence

Johan Auwerx, Norman Lionel Moullan, Lei Chen

Long noncoding RNAs (lncRNAs) are emerging regulators of biological processes in the vessel wall; however, their role in atherosclerosis remains poorly defined. We used RNA sequencing to profile lncRNAs derived specifically from the aortic intima of Ldlr(- ...

AMER ASSOC ADVANCEMENT SCIENCE2020

The onset of cardiovascular disease in mice: an image-based, computational-experimental approach

Lydia Aslanidou

In a number of cardiovascular diseases, the paucity of longitudinal human data hinders our understanding of disease evolution and forestalls the discovery of new therapeutic strategies. We therefore heavily rely on animal models to elucidate the mechanisms ...

EPFL2019

Co-localization of microstructural damage and excessive mechanical strain at aortic branches in Angiotensin-II-infused mice

Nikolaos Stergiopoulos, Lydia Aslanidou, Bram Trachet, Goran Lovric, Mauro Ferraro, Patrick Segers

Animal models of aortic aneurysm and dissection can enhance our limited understanding of the etiology of these lethal conditions particularly because early-stage longitudinal data are scant in humans. Yet, the pathogenesis of often-studied mouse models and ...

2019

On the importance of the nonuniform aortic stiffening in the hemodynamics of physiological aging

Nikolaos Stergiopoulos, Bram Trachet, Vasiliki Bikia, Stamatia Zoi Pagoulatou

Mathematical models of the arterial tree constitute a valuable tool to investigate the hemodynamics of aging and pathology. Rendering such models as patient specific could allow for the assessment of central hemodynamic variables of clinical interest. Howe ...

AMER PHYSIOLOGICAL SOC2019

Mapping the site-specific accuracy of loop-based local pulse wave velocity estimation and reflection magnitude: a 1D arterial network model analysis

Nikolaos Stergiopoulos, Patrick Segers

Objective: Local pulse wave velocity (PWV) can be estimated from the waterhammer equation and is an essential component of wave separation analysis. However, previous studies have demonstrated inaccuracies in the estimations of local PWV due to the presenc ...

2019

Propagation-based phase-contrast synchrotron imaging of aortic dissection in mice: from individual elastic lamella to 3D analysis

Nikolaos Stergiopoulos, Lydia Aslanidou, Bram Trachet, Marco Stampanoni, Patrick Segers

In order to show the advantage and potential of propagation-based phase-contrast synchrotron imaging in vascular pathology research, we analyzed aortic medial ruptures in BAPN/AngII-infused mice, a mouse model for aortic dissection. Ascending and thoraco-a ...

Nature Research2018

Improvement of a Closed Chest Porcine Myocardial Infarction Model by Standardization of Tissue and Blood Sampling Procedures

Jonas Alfred Karl Wilbs

Myocardial ischemia reperfusion (I/R) injury contributes to almost half of the necrotic area after myocardial infarction. To date there is no approved drug to prevent or reduce myocardial I/R injury. The study and understanding of the pathophysiological me ...

JOURNAL OF VISUALIZED EXPERIMENTS2018