Publications related to Heart valve

A mathematical model that integrates cardiac electrophysiology, mechanics, and fluid dynamics: Application to the human left heart

We propose a mathematical and numerical model for the simulation of the heart function that couples cardiac electrophysiology, active and passive mechanics and hemodynamics, and includes reduced models for cardiac valves and the circulatory system. Our mod ...

Wiley2023

The Impact of Left Ventricular Performance and Afterload on the Evaluation of Aortic Valve Stenosis: A 1D Mathematical Modeling Approach

Nikolaos Stergiopoulos

The transaortic valvular pressure gradient (TPG) plays a central role in decision-making for patients suffering from severe aortic stenosis. However, the flow-dependence nature of the TPG makes the diagnosis of aortic stenosis challenging since the markers ...

MDPI2023

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

A comprehensive mathematical model for cardiac perfusion

Alfio Quarteroni, Francesco Regazzoni, Christian Vergara

The aim of this paper is to introduce a new mathematical model that simulates myocardial blood perfusion that accounts for multiscale and multiphysics features. Our model incorporates cardiac electrophysiology, active and passive mechanics, hemodynamics, v ...

Nature Portfolio2023

Impact of atrial fibrillation on left atrium haemodynamics: A computational fluid dynamics study

Alfio Quarteroni, Luca Dede'

We analyse the haemodynamics of the left atrium, highlighting differences between healthy individuals and patients affected by atrial fibrillation. The computational study is based on patient-specific geometries of the left atria to simulate blood flow dyn ...

PERGAMON-ELSEVIER SCIENCE LTD2022

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

An Implantable Inductive Sensor for Direct and Continuous Monitoring of the Pulmonary Artery Cross-Sectional Area

Marco Mattavelli, Catherine Dehollain, Diego Ruben Barrettino, Kerim Türe, Mustafa Besirli

This paper presents a novel method for the measure of the cross-sectional area (CSA) of an artery to be used for the direct and continuous (24/7) monitoring of cardiac output (CO). The method is based on the inductance change of an anchoring loop mounted o ...

IEEE2022

Concurrent Evolution of Biomechanical and Physiological Parameters With Running-Induced Acute Fatigue

Kamiar Aminian, Anisoara Ionescu, Salil Apte, Gaëlle Prigent, Vincent Gremeaux

Understanding the influence of running-induced acute fatigue on the homeostasis of the body is essential to mitigate the adverse effects and optimize positive adaptations to training. Fatigue is a multifactorial phenomenon, which influences biomechanical, ...

FRONTIERS MEDIA SA2022

Actuator, valve actuator unit and valve

Herbert Shea, Fabio Beco Albuquerque

An actuator (22) comprises at least one actuator body (32) of dielectric elastomeric material and two electrodes (34, 36) being attached to opposite surfaces of the actuator body (32), respectively. At least one of the actuator body (32) and at least one o ...

2022

Preliminary Study of Pressure Self-Sensing Miniature Magnetorheological Valves

Yves Perriard, Yoan René Cyrille Civet, Christian Köchli, Sofia Lydia Ntella, Kenny Jeanmonod, Minh Trung Duöng

Magnetorheological (MR) valves have been included in many innovative engineering systems, such as dampers, clutches, or brakes, with different fields of application. Their role serves actuation purposes, while integrated displacement and velocity sensing i ...

IEEE2021

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

Morphomechanical Model Of The Torsional C-Looping In The Embryonic Heart

Alfio Quarteroni

Before septation processes shape its four chambers, the embryonic heart is a straight tube that spontaneously bends and twists breaking the left-right symmetry. In particular, the heart tube is subjected to a cell remodeling inducing ventral bending and de ...

SIAM PUBLICATIONS2021

Hemodynamics of the heart's left atrium based on a Variational Multiscale-LES numerical method

Alfio Quarteroni, Filippo Menghini

In this paper, we investigate the haemodynamics of a left atrium (LA) by proposing a computational model suitable to provide physically meaningful fluid dynamics indications and detailed blood flow characterization. In particular, we consider the incompres ...

ELSEVIER2021

An image-based computational hemodynamics study of the Systolic Anterior Motion of the mitral valve

Alfio Quarteroni, Luca Dede', Christian Vergara, Marco Fedele

Systolic Anterior Motion (SAM) of the mitral valve - often associated with Hypertrophic Obstructive Cardiomyopathy (HOCM) - is a cardiac pathology in which a functional subaortic stenosis is induced during systole by the mitral leaflets partially obstructi ...

PERGAMON-ELSEVIER SCIENCE LTD2020

Zinc complexation improves angiotensin II receptor type 1 blockade and in vivo antihypertensive activity of telmisartan

Nikolaos Stergiopoulos, Augusto Martins Lima, Valeria Romina Martinez

Background: Angiotensin II receptor blockers were designed as therapeutic agents to block the binding site of the angiotensin II receptor type 1 (AT1R). Methodology: The structure of telmisartan was modified by coordination to the biometal Zn(II), resultin ...

FUTURE SCI LTD2021

Acute effects of transcatheter aortic valve replacement on the ventricular-aortic interaction

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

Transcatheter aortic valve replacement (TAVR) is increasingly used to treat severe aortic stenosis (AS) patients. However, little is known regarding the direct effect of TAVR on the ventricular-aortic interaction. In the present study, we aimed to investig ...

AMER PHYSIOLOGICAL SOC2020

Design optimization of Miniature Magnetorheological Valves with Self-Sensing Capabilities Used for a Wearable Medical Application

Yves Perriard, Yoan René Cyrille Civet, Sofia Lydia Ntella, Minh Trung Duöng

Magnetorheological (MR) fluids are materials characterized as “intelligent” since their rheological properties may be controlled by the excitation of an external magnetic field. The application of the latter brings the fluid from a liquid to a semi-solid s ...

IEEE2020

Computational fluid dynamics of blood flow in an idealized left human heart

Alfio Quarteroni, Filippo Menghini

We construct an idealized computational model of the left human heart for the study of the blood flow dynamics in the left atrium and ventricle. We solve the Navier-Stokes equations in the ALE formulation and we prescribe the left heart wall displacement b ...

Wiley2019

A 1D computer model of the arterial circulation in horses: An important resource for studying global interactions between heart and vessels under normal and pathological conditions

Nikolaos Stergiopoulos, Patrick Segers

Arterial rupture in horses has been observed during exercise, after phenylephrine administration or during parturition (uterine artery). In human pathophysiological research, the use of computer models for studying arterial hemodynamics and understanding n ...

2019

Latchable microfluidic valve arrays based on shape memory polymer actuators

Herbert Shea, Nadine Besse, Bekir Aksoy

We report arrays of latching microfluidic valves based on shape memory polymers (SMPs), and show their applications as reagent mixers and as peristaltic pumps. The valve design takes advantage of the SMP's multiple stable shapes and over a hundred-fold sti ...

2019