Publications associées à Wiggers diagram

On the similarity between aortic and carotid pressure diastolic decay: a mathematical modelling study

Nikolaos Stergiopoulos, Georgios Rovas, Sokratis Anagnostopoulos, Vasiliki Bikia

Aortic diastolic pressure decay (DPD) has been shown to have considerable pathophysiological relevance in the assessment of vascular health, as it is significantly affected by arterial stiffening. Nonetheless, the aortic pressure waveform is rarely availab ...

Nature Portfolio2023

In vivo application and validation of a novel noninvasive method to estimate the end-systolic elastance

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

Accurate assessment of the left ventricular (LV) systolic function is indispensable in the clinic. However, estimation of a precise index of cardiac contractility, i.e., the end-systolic elastance (E-es), is invasive and cannot be established as clinical r ...

2021

Estimating Left Ventricular Elastance from Aortic Flow Waveform, Ventricular Ejection Fraction, and Brachial Pressure: An In Silico Study

Nikolaos Stergiopoulos, Stamatia Zoi Pagoulatou

Although left ventricular end-systolic elastance (E-es) serves as a major index of cardiac contractility, a widely-accepted noninvasive estimation of E-es does not exist. To overcome this limitation, we developed a two-step inverse method that allows for i ...

SPRINGER2018

Method and Device for Non-Invasive Blood Pressure Measurement

David Atienza Alonso, Francisco Javier Rincon Vallejos, Srinivasan Murali, Alair Dias Junior

A system for measuring blood pressure of a user that comprises an ElectroCardioGram (ECG) circuit with at least two ECG electrodes configured to obtain an electrical activity of a heart of the user by measuring the electrical signals detected at the at lea ...

2017

The "systolic volume balance" method for the noninvasive estimation of cardiac output based on pressure wave analysis

Nikolaos Stergiopoulos, Orestis Vardoulis

Papaioannou TG, Vardoulis O, Stergiopulos N. The "systolic volume balance" method for the noninvasive estimation of cardiac output based on pressure wave analysis. Am J Physiol Heart Circ Physiol 302: H2064-H2073, 2012. First published March 16, 2012; doi: ...

2012

Analysis of electrocardiograms during atrial fibrillation

Jean-Marc Vesin, Vincent Jacquemet, Lukas Kappenberger

The research discussed in this article is motivated by the search for an optimal classification of the different types of atrial fibrillation (AF) on the basis of recorded atrial signals. This would facilitate the selection of an optimal therapy. This arti ...

2006

The effect of a myocardial infarction on the normalized time-varying elastance curve

Nikolaos Stergiopoulos, Rafaela Fernandes Da Silva, David Jegger

It has been suggested that the shape of the normalized time-varying elastance curve [E(n)(t(n))] is conserved in different cardiac pathologies. We hypothesize, however, that the E(n)(t(n)) differs quantitatively after myocardial infarction (MI). Sprague-Da ...

2006

Nonlinear isochrones in murine left ventricular pressure-volume loops: how well does the time-varying elastance concept hold?

Nikolaos Stergiopoulos, Patrick Segers, Nico Westerhof

The linear time-varying elastance theory is frequently used to describe the change in ventricular stiffness during the cardiac cycle. The concept assumes that all isochrones (i.e., curves that connect pressure-volume data occurring at the same time) are li ...

2005

Calcium dynamics and intercellular communication in arterial smooth muscle cells

Mathieu Lamboley

This thesis is a contribution to the field of cellular communication in arteries during vasomotion, i.e. rhythmic and spontaneous diameter oscillations of arteries. Investigating how individual smooth muscle cells (SMCs) and endothelial cells (ECs) calcium ...

EPFL2005