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Strain examinations of the left ventricle phantom by ultrasound and multislices computed tomography imaging

Trawiński Z., Wójcik J., Nowicki A., Olszewski R., Balcerzak A., Frankowska E., Zegadło A., Rydzyński P.

Biocybernetics and Biomedical Engineering

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2015

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Vol. 35, no. 4

255--263

EN

The main aim of this study was to verify the suitability of the hydrogel sonographic model of the left ventricle (LV) in the computed tomography (CT) environment and echocardiography and compare the radial strain calculations obtained by two different techniques: the speckle tracking ultrasonography and the multislices computed tomography (MSCT). The measurement setup consists of the LV model immersed in a cylindrical tank filled with water, hydraulic pump, the ultrasound scanner, hydraulic pump controller, pressure measurement system of water inside the LV model, and iMac workstation. The phantom was scanned using a 3.5 MHz Artida Toshiba ultrasound scanner unit at two angle positions: 0° and 25°. In this work a new method of assessment of RF speckles' tracking. LV phantom was also examined using the CT 750 HD 64-slice MSCT machine (GE Healthcare). The results showed that the radial strain (RS) was independent on the insonifying angle or the pump rate. The results showed a very good agreement, at the level of 0.9%, in the radial strain assessment between the ultrasound M-mode technique and multislice CT examination. The study indicates the usefulness of the ultrasonographic LV model in the CT technique. The presented ultrasonographic LV phantom may be used to analyze left ventricle wall strains in physiological as well as pathological conditions. CT, ultrasound M-mode techniques, and author's speckle tracking algorithm, can be used as reference methods in conducting comparative studies using ultrasound scanners of various manufacturers.

2

Mathematical and Ultrasonographic Model of the Left Ventricle : in Vitro Studies

Olszewski R., Trawiński Z., Wójcik J., Nowicki A.

Archives of Acoustics

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2012

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Vol. 37, No. 4

583-595

EN

The main objective of this study is to develop an echocardiographic model of the left ventricular and numerical modeling of the speckles- markers tracking in the ultrasound (ultrasonographic) imaging of the left ventricle. The work is aimed at the creation of controlled and mobile environment that enables to examine the relationships between left ventricular wall deformations and visualizations of these states in the form of echocardiographic imaging and relations between the dynamically changing distributions of tissue markers of studied structures.

3

Biventricular pacemaker synchronization: A numerical cardiocirculatory model application to reproduce in vivo data

Di Molfetta A., De Lazzari C., Ferrari G., Moscariello F., Aguzzi G., Fresiello L., Darowski M., Trivella M. G., Alessandri N

Biocybernetics and Biomedical Engineering

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2010

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Vol. 30, no. 1

3-15

EN

Cardiac Resynchronization Therapy (CRT) seems to be the most encouraging treatment to limit the damages of ventricular remodelling in patients with moderate-severe cardiac insufficiency. Mathematical modelling of the cardiovascular system is a tool potentially useful to understand how the Biventricular Pacemaker (BPM) must be synchronised during CRT. In this work a computer simulator reproduces clinical data measured, on different patients affected by asynchronous ventricular contraction, before and after CRT. Three patients, affected by asynchronous ventricular contraction, were monitored before and after biventricular stimulation through CRT. Measured and simulated data were compared. Results show that the software simulator can well reproduce in vivo data. Besides, simulated results from BPM together with drug therapy are in accordance with literature data. Numerical modelling could be a useful tool to optimize the BPM synchronization.

4

Optimization of a left ventricular assist device using numerical simulation

Verkerke G. J., Mihaylow D., Geerstema A. A., Rakhorst G.

Biocybernetics and Biomedical Engineering

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2003

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Vol. 23, no. 2

35-41

EN

The PUCA pump is a left ventricular assist device especially meant for a fast introduction by using minimal surgery. An extracorporeal located membrane pump is coupled to a transarterial catheter that enters the body via a superficial artery and ends in the LV. Pump efficacy is influenced by several pump parameters. To find the best efficacy, a numerical model of the PUCA pump coupled with the circulatory system can be used. For the PUCA pump, the best configuration is a stroke volume of 50 cc and pump: heart frequency of 1 : 2 that starts ejection at the beginning of diastole.