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Biocompatible Evaluation Of Biomaterials Used In The New Polish Extracorporeal Pulsatile Heart Assist Device ReligaHeart EXT

Gonsior M., Kustosz R., Kościelniak-Ziemniak M., Wierzchoń T.

Archives of Metallurgy and Materials

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2015

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Vol. 60, iss. 3

2271--2278

EN

The innovative extracorporeal heart support device ReligaHeart (RH EXT) has been developed, based on POLVAD ventricular assist device clinical experience, collected in more than 300 patient applications. The innovative surface engineering technologies are applied in ReligaHeart EXT device. The pump is manufactured of new generation, modified surface structure, biocompatible polyurethanes, and equipped with original tilting disc valves, Moll type. The valve ring is made of titanium alloy, TiN+Ti2N+αTi(N) diffusive layer modified, produced with glow discharge at plasma potential, in order to obtain the lowest thrombogenicity. The valve disc is made of polyether ether ketone. The complex in vitro and in vivo biological evaluations were performed, confirming both biomaterials biocompatible properties and device biocompatibility, proved in 30 days animal heart support.

PL

Na podstawie doświadczeń klinicznych protezy serca POLVAD, zastosowanej u ponad 300 pacjentów, opracowano zmodernizowaną pozaustrojową pompę wspomagania serca ReligaHeart EXT (RH EXT). W protezie RH EXT zostały zastosowane innowacyjne technologie inżynierii powierzchni. Pompa wykonana jest z nowej generacji biozgodnych poliuretanów o modyfikowanej strukturze powierzchni i jest wyposażona w oryginalne zastawki dyskowe typu Moll. Pierścień zastawki jest wykonany ze stopu tytanu z dyfuzyjną warstwą TiN+Ti2N+αTi(N) wytwarzaną w procesie obróbki jarzeniowej na potencjale plazmy, dla osiągnięcia niskiej trombogenności. Dysk zastawki jest wykonany z polieteroketonu. Wykonano kompleksową ocenę biozgodności in vitro i in vivo, potwierdzając biozgodne własności biomateriałów i protezy RH EXT, także w czasie 30 dniowego wspomagania serca w modelu zwierzęcym.

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Hybrid system of ECG signal acquisition and QRS complexes detection for special medical devices synchronization

Komorowski D., Malcher A., Pietraszek S.

Journal of Medical Informatics & Technologies

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2013

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Vol. 22

227--234

EN

Some medical devices such as mechanical circulatory support systems and defibrillators require synchronization with the appropriate phase of the cardiac cycle of the patient. This paper presents a description of the electrocardiographic (ECG) signal amplifier and QRS detector designed for use with such devices. The detector system was built using a programmable analog array AN231E04 and the ECG amplifier with an analog-digital (A/D) converter based on a programmable circuit (front-end) ADS129x. By using the programmable elements and exploiting the potential of dynamic analog matrix reconfiguration, the presented detector achieved the desired features, such as low latency of QRS detection, automatic gain control and the ability to change the time constant by software. High-resolution of the A/D converter in the ADS1298x and the possibility of programming the gain of the amplifier allow the acquisition of the ECG signal acquired from different types of electrodes: disposable standard, epicardial or endocavitary. The tests of the prototype system proved that it is highly effective for the detection of QRS complexes in ECG waveforms recorded from all kinds of electrodes.

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Determination of stroke volume of the ventricular assist device using bioimpedance method

Sobotnicki A., Gacek A., Pałko T., Mocha J., Badura G., Czerw M.

Journal of Medical Informatics & Technologies

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2013

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Vol. 22

235--241

EN

The stroke volume of pulsatile ventricular assist device (VAD) is one of the key clinical indicators to evaluate the adequacy of the process of mechanical heart assistance and ensuring the patient’s safety. In order to evaluate the volume changes in VAD blood chamber, a bioimpedance method was applied, based on volumetric electric conductivity of the blood. Periodic changes in VAD volume during its operation result in a pulsatile impedance waveform; its amplitude in the subperiods of filling and ejection correlates with blood volume in the chamber. The paper presents the method of analysis of the bioimpedance signal recorded in VAD blood chamber with a reference to the classical method of analysing the cardioimpedance signal from the patient’s thorax. The paper also presents the results of determining stroke volume of blood chamber based on an empirical formula that has been developed.