Acoustic system for the estimation of the temporary blood chamber volume of the POLVAD heart supporting prosthesis

Konieczny, Grzegorz; Opilski, Z.; Pustelny, T.; Gawlikowski, M.

doi:10.1186/1475-925x-11-72

Cited by 9 publications

(6 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Idea of the optical measurement method based on reectance measurements[10].The basic idea of the optical system based on reectance measurements is shown inFig. 1.…”

mentioning

confidence: 99%

Optical Sensor for Measurements of the Blood Chamber Volume in the POLVAD Prosthesis - Static Measurements

2013

View full text Add to dashboard Cite

The paper presents results of extended static measurements of a newly developed optical system for temporary blood chamber volume measurements in the Polish Ventricular Assist Device. The paper additionally introduces a modied measurement stand and improvements of the measurements. Exemplary results acquired with principal components analysis are shown and future development plans of an optical measurement system are stated.

show abstract

“…Idea of the optical measurement method based on reectance measurements[10].The basic idea of the optical system based on reectance measurements is shown inFig. 1.…”

mentioning

confidence: 99%

Optical Sensor for Measurements of the Blood Chamber Volume in the POLVAD Prosthesis - Static Measurements

2013

View full text Add to dashboard Cite

show abstract

“…The two-scale model [11] of Polish ventricular assist device [12,13] developed in the authors' finite element code was composed of a macro-model of blood chamber [14] and a micro-model [15] of wall: TiN and Bionate II (thermoplastic polycarbonate-urethane). The numerical analysis of stress and strain states [16] confirmed the possibility of fracture [17] based on localization of zones of the biggest values of triaxiality factor.…”

Section: Introductionmentioning

confidence: 99%

Numerical And Experimental Analysis Of Fracture Of Athrombogenic Coatings Deposited On Ventricular Assist Device In Micro-Shear Test

Kopernik¹,

Milenin²,

Kąc³

2015

Archives of Metallurgy and Materials

View full text Add to dashboard Cite

The Polish left ventricular assist device (LVAD -RELIGA EXT) will be made of thermoplastic polycarbonate-urethane (Bionate II) with deposited athrombogenic nano-coatings: gold (Au) and titanium nitride (TiN). Referring to the physical model, the two-scale model of LVAD developed in the previous works in the authors' finite element code is composed of a macro-model of blood chamber and a micro-model of wall: TiN, Au and Bionate II. The numerical analysis of stress and strain states confirmed the possibility of fracture based on localization of zones of the biggest values of triaxiality factor. The introduction of Au interlayer between TiN and polymer improved the toughness of the connection, and increased the compressive residual stress in the coating what resulted in reduction of stress and strain close to the boundary between substrate and coating.However, the proper design of multilayer wall of the medical device requires the introduction of the real stress and strain states in the deposited coatings. The characteristics of TiN nano-coating such as residual stress, material model and fracture model were determined in the previously completed studies such as experimental and numercial nanoindentation tests, profilometry studies and in situ SEM's micro-tension tests.The experimental in situ SEM's micro-shear test was performed in the present paper and the corresponding numerical model of the test was also developed, and then, interpreted. The critical strains taken from experiment and considered as the effective strains in the model of test are the values which are the function of triaxiality factors for the tested samples. The developed in the authors' FE code model of multilayer wall of VAD enriched with critical strain determined in the present paper enables prediction of fracture.Keywords: micro-shear test, finite element method (FEM), fracture, ventricular assist device (VAD), titanium nitride (TiN), gold (Au) Polska lewa komora wspomagania pracy serca (LVAD -RELIGA EXT) zostanie wykonana z termoplastycznego poliwęgla-no-uretanu (Bionate II) z naniesionymi atrombogennymi powłokami: złota (Au) i azotku tytanu (TiN). W odniesieniu do modelu fizycznego, dwuskalowy model komory LVAD opracowany we wcześniejszych pracach w autorskim kodzie elementów skończonch jest złożony z modelu makro czaszy krwistej i z mikro-modelu ściany: TiN, Au i Bionate II. Analiza numeryczna stanów naprężenia i odkształcenia potwierdziła prawdopodobieństwo pękania poprzez zlokalizowanie stref o największej wartości współczynnika naprężenia trójosiowego. Wprowadzenie międzywarstwy złota pomiędzy TiN i polimer poprawiło wytrzymałość tego połączenia i powiększyło ściskające naprężenie własne w powłoce, co doprowadziło do redukcji naprężenia i odkształcenia blisko granicy pomiędzy podłożem i powłoką.Jednakże, właściwy projekt wielowarstwowej ściany urządzenia medycznego wymaga wprowadzenia rzeczywistych stanów naprężeń i odkształceń w naniesionych powłokach. Charakterystyki powłok TiN takie jak naprężenie własne, model materiału i model pęk...

show abstract

“…Both methods, however, required frequent calibration cycles, using the reference method. There were many other approaches to solve that problem in the pneumatic type of VAD [ 15 – 18 ]. One of the promising solutions developed in our Department was based on the concept of Helmholtz’s acoustic resonator [ 17 – 19 ].…”

Section: Introductionmentioning

confidence: 99%

Optoelectronic system for the determination of blood volume in pneumatic heart assist devices

et al. 2015

Self Cite

View full text Add to dashboard Cite

BackgroundThe following article describes the concept of optical measurement of blood volume in ventricular assist devices (VAD’s) of the pulsatile type. The paper presents the current state of art in blood volume measurements of such devices and introduces a newly developed solution in the optic domain. The objective of the research is to overcome the disadvantages of the previously developed acoustic method—the requirement of additional sensor chamber.MethodsThe idea of a compact measurement system has been introduced, followed by laboratory measurements. Static tests of the system have been presented, followed by dynamic measurements on a physical model of the human ventricular system. The results involving the measurements of blood chamber volume acquired by means of an optical system have been compared with the results acquired by means of the Transonic T410 ultrasound flow rate sensor (11PLX transducer, uncertainty ±5 %).ResultsPreliminary dynamic measurements conducted on the physical model of the human cardiovascular system show that the proposed optical measurement system may be used to measure the transient blood chamber volumes of pulsatile VAD’s with the uncertainties (standard mean deviation) lower than 10 %.ConclusionsThe results show that the noninvasive measurements of the temporary blood chamber volume in the POLVAD prosthesis with the use of the developed optical system allows us to carry out accurate static and dynamic measurements.

show abstract

Acoustic system for the estimation of the temporary blood chamber volume of the POLVAD heart supporting prosthesis

Cited by 9 publications

References 17 publications

Optical Sensor for Measurements of the Blood Chamber Volume in the POLVAD Prosthesis - Static Measurements

Optical Sensor for Measurements of the Blood Chamber Volume in the POLVAD Prosthesis - Static Measurements

Numerical And Experimental Analysis Of Fracture Of Athrombogenic Coatings Deposited On Ventricular Assist Device In Micro-Shear Test

Optoelectronic system for the determination of blood volume in pneumatic heart assist devices

Contact Info

Product

Resources

About