Publications related to Defibrillation

Cardiovascular response to closed-loop intraneural stimulation of the right vagus nerve: a proof-of-concept study

Vagus nerve stimulation (VNS) is an FDA-approved technique for the neuromodulation of the autonomic nervous system. There are many therapeutic applications where VNS could be used as a therapy, such as cardiovascular diseases, epilepsy, depression, and inf ...

IEEE2023

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

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

Adaptation of a solid-state-Marx modulator for electroactive polymer

Yves Perriard, Yoan René Cyrille Civet, Thomas Guillaume Martinez, Morgan Almanza

Electroactive polymers show promising characteristic such as lightness, compactness, flexibility and large displacements making them a candidate for application in cardiac assist devices. This revives the need for quasi- square wave voltage supply switchin ...

2022

Control-oriented modeling and analysis of tubular dielectric elastomer actuators dedicated to cardiac assist devices

Yves Perriard, Yoan René Cyrille Civet, Thomas Guillaume Martinez, Armando Matthieu Walter, Ning Liu

This paper deals with the control-oriented modeling of a multilayered dielectric elastomer actuator based tube. The actuator is clamped at both sides and performs a radial displacement. The hyperelastic deformation and the viscoelastic performance, togethe ...

2022

Active force generation contributes to the complexity of spontaneous activity and to the response to stretch of murine cardiomyocyte cultures

Stéphanie Lacour

Cardiomyocyte cultures exhibit spontaneous electrical and contractile activity, as in a natural cardiac pacemaker. In such preparations, beat rate variability exhibits features similar to those of heart rate variability in vivo. Mechanical deformations and ...

WILEY2022

SPARE: A Spectral Peak Recovery Algorithm for PPG Signals Pulsewave Reconstruction in Multimodal Wearable Devices

David Atienza Alonso, Giulio Masinelli, Adriana Arza Valdes, Fabio Isidoro Tiberio Dell'Agnola

The photoplethysmographic (PPG) signal is an unobtrusive blood pulsewave measure that has recently gained popularity in the context of the Internet of Things. Even though it is commonly used for heart rate detection, it has been lately employed on multimod ...

2021

Energy Analysis of a Cardiac Assist Device based on Dielectric Elastomer Actuator through an Equivalent Electrical Circuit

Yves Perriard, Yoan René Cyrille Civet, Francesco Clavica, Jonathan André Jean-Marie Chavanne

Lumped parameter model and mock circulation loop are two tools commonly used in biomedical research to simulate cardiac system in order to study different assist devices. In this paper, a lumped parameter model is proposed to simulate a circulation loop. T ...

IEEE2021

Hardware-oriented pruning and quantization of Deep Learning models to detect life-threatening arrhythmias

Alexandre Schmid, Lizeth Gonzalez Carabarin

Wearable solutions based on Deep Learning (DL) for real-time ECG monitoring are a promising alternative to detect life-threatening arrhythmias. However, DL models suffer of a large memory footprint, which hampers their adoption in portable technologies. Th ...

IEEE2021

Design and modelling of a tubular dielectric elastomer actuator with constrained radial displacement as a cardiac assist device

Yves Perriard, Yoan René Cyrille Civet, Armando Matthieu Walter, Jonathan André Jean-Marie Chavanne

In this paper, we propose an improvement of a dielectric elastomer actuator (DEA) based augmented aorta. The actuator is a multi-layered tubular DEA subject to the internal pressure of the blood. When activated in synchronisation with the heart, the DEA su ...

IOP PUBLISHING LTD2021

Computational methods for live heart imaging with speed-constrained microscopes

Olivia Mariani

Imaging methods to capture the beating and developing heart inside embryonic animal models such as the zebrafish are a key component for the study of fundamental biological processes such as cardiac birth defects or tissue regeneration. However, live heart ...

EPFL2021

Mathematical and numerical models for the cardiac electromechanical function

Alfio Quarteroni, Francesco Regazzoni

This paper deals with the mathematical model that describes the function of the human heart. More specifically, it addresses the equations that express the electromechanical process, that is the mechanical deformation (contraction and relaxation) of the he ...

EUROPEAN MATHEMATICAL SOC-EMS2021

Towards an in vitro cardiac model: 3D environment, co-culture, alignment, and mechanical stimulation impact on cell behavior

Fatemeh Navaee

Our aim is to develop a 3D model unit of cardiac muscle: an in-vitro analog of the trabeculae carneae found in vivo. As a base hydrogel matrix for cardiomyocyte culture in 3D, we develop a blend of decellularized extracellular matrix (dECM) and fibrin. Thi ...

EPFL2021

An intergrid transfer operator using radial basis functions with application to cardiac electromechanics

Alfio Quarteroni

In the framework of efficient partitioned numerical schemes for simulating multiphysics PDE problems, we propose using intergrid transfer operators based on radial basis functions to accurately exchange information among different PDEs defined in the same ...

SPRINGER2020

Identification of material parameters of a tubular dielectric elastomer actuator for a cardiac assist device

Yves Perriard, Yoan René Cyrille Civet, Thomas Guillaume Martinez, Jonathan André Jean-Marie Chavanne

The recent development of Dielectric Elastomer Actuators (DEA) requires a new approach to the description of hyperelastic material when the architectures are more complex than a film of material. In this paper, we propose a new technique of identification ...

2020

Heart Rate Variability Triangular Index as a Predictor of Cardiovascular Mortality in Patients With Atrial Fibrillation

Jean-Marc Vesin, Vincent Schlageter

Background Impaired heart rate variability (HRV) is associated with increased mortality in sinus rhythm. However, HRV has not been systematically assessed in patients with atrial fibrillation (AF). We hypothesized that parameters of HRV may be predictive o ...

2020

Machine learning of multiscale active force generation models for the efficient simulation of cardiac electromechanics

Alfio Quarteroni, Francesco Regazzoni

High fidelity (HF) mathematical models describing the generation of active force in the cardiac muscle tissue typically feature a large number of state variables to capture the intrinsically complex underlying subcellular mechanisms. With the aim of drasti ...

2020

Biophysically detailed mathematical models of multiscale cardiac active mechanics

Alfio Quarteroni, Francesco Regazzoni

Author summary Computer-based numerical simulations of the heart are increasingly assuming a recognized role in the context of computational medicine and cardiology. They are based on mathematical models describing the different physical phenomena occurrin ...

2020

Outer loop and isthmus in ventricular tachycardia circuits: Characteristics and implications

Alfio Quarteroni, Andrea Manzoni, Luca Dede', Stefano Pagani

BACKGROUND The isthmus of ventricular tachycardia (VT) circuits has been extensively characterized. Few data exist regarding the contribution of the outer loop (OL) to the VT circuit. OBJECTIVE The purpose of this study was to characterize the electrophysi ...

2020

Biomechanics of diastolic dysfunction: a one-dimensional computational modeling approach

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

Diastolic dysfunction (DD) is a major component of heart failure with preserved ejection fraction (HFpEF). Accordingly. a profound understanding of the underlying biomechanical mechanisms involved in DD is needed to elucidate all aspects of HFpEF. In this ...

AMER PHYSIOLOGICAL SOC2020