Wyniki wyszukiwania - BazTech

Ograniczanie wyników

3 Biocybernetics and Biomedical Engineering

Znaleziono wyników: 3

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

A portable system for autoregulation and wireless control of sensorized left ventricular assist devices

Fontana R., Tortora G., Silvestri M., Vatteroni M., Dario P., Trivella M. G.

Biocybernetics and Biomedical Engineering

2016

Vol. 36, no. 2

366--374

End stage heart failure patients could benefit from left ventricular assist device (LVAD) implantation as bridge to heart transplantation or as destination therapy. However, LVAD suffers from several limitations, including the presence of a battery as power supply, the need for cabled connection from inside to outside the patient, and the lack of autonomous adaptation to the patient metabolic demand during daily activity. The authors, in this wide scenario, aim to contribute to advancement of the LVAD therapy by developing the hardware and the firmware of a portable autoregulation unit (ARU), able to fulfill the needs of sensorized VAD in terms of physic/physiological data storing, continuous monitoring, wireless control from the external environment and automatic adaptation to patient activities trough the implementation of autoregulation algorithms. Moreover, in order to answer the rules and safety requirements for implantable biomedical devices, a user control interface (UCI), was developed and associated to the ARU for an external manual safe control. The ARU and UCI functionalities and autoregulation algorithms have been successfully tested on bench and on animal, with a response time of 1 s for activating autoregulation algorithms. Animal experiments showed as the presence of the ARU do not affect the animal cardiovascular system, giving a proof of concept of its applicability in vivo.

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

2010

Vol. 30, no. 1

3-15

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.

Interaction between left ventricle mechanics and myocardial blood flow

Trivella M. G., Pelosi G., Neglia D., L'Abbate A.

Biocybernetics and Biomedical Engineering

2008

Vol. 28, no. 1

3-16

The interaction between coronary circulation and left ventricular mechanics has been studied in animal models as well as investigated in humans. Here we review the results of experimental studies performed at the Institute of Clinical Physiology: the separate contribution of preload and after load on coronary pressure-flow, pressure-volume and volume-flow relationships; single beat as well as averaged instantaneous loops, both during autoregulation and under maximal vasodilation. We then present the results of animal studies on estimate of functional microvascular architecture and its relationship with myocardial blood flow heterogeneity. Finally, we report on clinical applications performed in various models of left ventricular dysfunction as myocardial ischemia, hypertrophic cardiomyopathy, dilated cardiomyopathy and secondary hypertrophy, aimed at investigating the interaction between coronary flow and abnormal left ventricular mechanics.