Hemodynamic modelling in the calf — A pilot study

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68081731%3A_____%2F16%3A00474796" target="_blank" >RIV/68081731:_____/16:00474796 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.22489/CinC.2016.149-433" target="_blank" >http://dx.doi.org/10.22489/CinC.2016.149-433</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.22489/CinC.2016.149-433" target="_blank" >10.22489/CinC.2016.149-433</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Hemodynamic modelling in the calf — A pilot study

Popis výsledku v původním jazyce

With increasing age, the cardiovascular system loses its efficiency. The goal of this work was to investigate the hemodynamic system response to a head-up tilt test in two groups of different aged people. We used a model for describing this response in the right calf based on a non-invasive, non-occlusive, bioimpedance signal measurement technique. A decrease in the bioimpedance value in the calf during the head-up tilt test is associated with the accumulation of blood in the calf, which can be expressed by a model parameter. Subjects were examined in both a head-up tilt test and a supine position. 50 healthy non-smoking volunteers were divided into two groups according to age. The impedance signal during the tilt test for each subject was fitted by a model exponential function: Z0 model EF(t) =A exp(-t/B)+C, where Z0 model EF(t) is the calculated model of electrical impedance in the calf by an exponential function, A is the amplitude of impedance change, B is the time constant of the impedance decrease, C is the value of the steady state after the tilt test and t denotes time. A lower time constant B shows a faster filling of the vascular system in the investigated part. The Mann-Whitney test (p-value<,0.005) revealed that the time constant B for the older group was significantly lower than for the young group (145.24+/- 80.28 vs. 239.23+/-136.59 sec.). A lower time constant value means a faster response to blood filling in the lower limbs and directly reflects decreased vessel elasticity. This time constant was lower in the older group. The results show increased vessel stiffness in old age and could lead to a non-invasive evaluating the cardiovascular system state.

Název v anglickém jazyce

Hemodynamic modelling in the calf — A pilot study

Popis výsledku anglicky

With increasing age, the cardiovascular system loses its efficiency. The goal of this work was to investigate the hemodynamic system response to a head-up tilt test in two groups of different aged people. We used a model for describing this response in the right calf based on a non-invasive, non-occlusive, bioimpedance signal measurement technique. A decrease in the bioimpedance value in the calf during the head-up tilt test is associated with the accumulation of blood in the calf, which can be expressed by a model parameter. Subjects were examined in both a head-up tilt test and a supine position. 50 healthy non-smoking volunteers were divided into two groups according to age. The impedance signal during the tilt test for each subject was fitted by a model exponential function: Z0 model EF(t) =A exp(-t/B)+C, where Z0 model EF(t) is the calculated model of electrical impedance in the calf by an exponential function, A is the amplitude of impedance change, B is the time constant of the impedance decrease, C is the value of the steady state after the tilt test and t denotes time. A lower time constant B shows a faster filling of the vascular system in the investigated part. The Mann-Whitney test (p-value<,0.005) revealed that the time constant B for the older group was significantly lower than for the young group (145.24+/- 80.28 vs. 239.23+/-136.59 sec.). A lower time constant value means a faster response to blood filling in the lower limbs and directly reflects decreased vessel elasticity. This time constant was lower in the older group. The results show increased vessel stiffness in old age and could lead to a non-invasive evaluating the cardiovascular system state.

Druh

D - Stať ve sborníku

CEP obor

—

OECD FORD obor

20601 - Medical engineering

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2016

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název statě ve sborníku

Computing in Cardiology (CinC) 2016

ISBN

978-1-5090-0896-4

ISSN

2325-8861

e-ISSN

—

Počet stran výsledku

4

Strana od-do

525-528

Název nakladatele

Computing in Cardiology

Místo vydání

Vencouver

Místo konání akce

Vencouver

Datum konání akce

11. 9. 2016

Typ akce podle státní příslušnosti

WRD - Celosvětová akce

Kód UT WoS článku

000405710400132