Publications related to Hemodynamics

A comprehensive stroke risk assessment by combining atrial computational fluid dynamics simulations and functional patient data

Stroke, a major global health concern often rooted in cardiac dynamics, demands precise risk evaluation for targeted intervention. Current risk models, like the CHA 2 DS 2 -VASc \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepa ...

Nature Portfolio2024

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

Reduced order modeling of parametrized pulsatile blood flows: Hematocrit percentage and heart rate

Ricardo Reyes Sotomayor

This paper numerically evaluates the accuracy and performance of a stabilized finite element Reduced Order Modelling (ROM) approach that is designed to simulate pulsatile blood flows. The method is able to estimate fluid flow parametric solutions of intere ...

PERGAMON-ELSEVIER SCIENCE LTD2023

lifex-cfd: An open-source computational fluid dynamics solver for cardiovascular applications

Alfio Quarteroni, Luca Dede', Marco Fedele

Computational fluid dynamics (CFD) is an important tool for the simulation of the cardiovascular function and dysfunction. Due to the complexity of the anatomy, the transitional regime of blood flow in the heart, and the strong mutual influence between the ...

Elsevier2023

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

Integrated Electronics for Deep Implants to Remotely Monitor Hemodynamics

Mustafa Besirli

The integration of technology in the medical field has greatly improved accuracy in diagnoses, thus leading to more effective treatments. Wearable and implantable medical devices offer great potential for remote patient monitoring, particularly for heart f ...

EPFL2023

Quantification of the Phenomena Affecting Reflective Arterial Photoplethysmography

Nikolaos Stergiopoulos, Georgios Rovas, Vasiliki Bikia

Photoplethysmography (PPG) is a widely emerging method to assess vascular health in humans. The origins of the signal of reflective PPG on peripheral arteries have not been thoroughly investigated. We aimed to identify and quantify the optical and biomecha ...

MDPI2023

Left cardiac vagotomy rapidly reduces contralateral cardiac vagal electrical activity in anesthetized Gottingen minipigs

Silvestro Micera, Ivo Strauss

Background: The impact of acute unilateral injury on spontaneous electrical activity in both vagus nerves at the heart level is poorly understood. We investigated the immediate neuroelectrical response after right or left cardiac vagal nerve transection (V ...

Elsevier Ireland Ltd2023

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

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

Efficient approximation of cardiac mechanics through reduced-order modeling with deep learning-based operator approximation

Alfio Quarteroni, Andrea Manzoni

Reducing the computational time required by high-fidelity, full-order models (FOMs) for the solution of problems in cardiac mechanics is crucial to allow the translation of patient-specific simulations into clinical practice. Indeed, while FOMs, such as th ...

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

Revisiting the role of friction coefficients in granular collapses: confrontation of 3-D non-smooth simulations with experiments

Gauthier Paul Daniel Marie Rousseau

In this paper, transient granular flows are examined both numerically and experimentally. Simulations are performed using the continuous three-dimensional (3-D) granular model introduced in Daviet & Bertails-Descoubes (ACM Trans. Graph., vol. 35, no. 4, 20 ...

Cambridge University Press2023

Cardiovascular monitoring system

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

A cardiovascular monitoring system for measuring at least cardiac output comprises an implantable unit (2) configured for placement in a section of artery of a patient and a portable external unit (1) configured for mounting against or close to a patient's ...

2022

Validation of a Non-invasive Inverse Problem-Solving Method for Stroke Volume

Nikolaos Stergiopoulos, Georgios Rovas, Vasiliki Bikia, Stamatia Zoi Pagoulatou, Emma Marie Roussel

Stroke volume (SV) is a major biomarker of cardiac function, reflecting ventricular-vascular coupling. Despite this, hemodynamic monitoring and management seldomly includes assessments of SV and remains predominantly guided by brachial cuff blood pressure ...

FRONTIERS MEDIA SA2022

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

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

Ultra-high voltage, low power and energy recovering electronics for dielectric elastomer actuators

Raphaël Johannes Charles Mottet

Heart failure is a cardiovascular disease affecting between 1 and 2% of the population of developed countries alone - more than 10 million people - with this number bound to increase due to the ageing of the population. This condition starts to develop its ...

EPFL2022

Longitudinal interrogation of sympathetic neural circuits and hemodynamics in preclinical models

Grégoire Courtine, Quentin Barraud, Jordan Squair, Matthieu Pierre Gautier, Victor Perez Puchalt, Loïs Thomas Romain Mahe, Rémi Bernard René Hudelle, Jan Elaine Cuevas Soriano, Suje Amir

Neurological disorders, including spinal cord injury, result in hemodynamic instability due to the disruption of supraspinal projections to the sympathetic circuits located in the spinal cord. We recently developed a preclinical model that allows the ident ...

NATURE PORTFOLIO2022

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