Abstract:
:Measurement of the instantaneous pressure-volume relationship of the left ventricle is fundamental to the study of ventricular mechanics. In order to effectively investigate this relationship, it is necessary to vary and control the time course of ventricular volume change in a variety of prescribed manners. In the past, we used an analog circuit to generate command signals for a servo-pump system which controlled ventricular volume. The use of analog control limited the variety of volume waveforms which could be generated. To overcome this limitation, we developed a new system in which the servo-pump is controlled by an inexpensive microprocessor based computer, capable of generating an unlimited repertoire of volume waveforms. The computer system also made possible the use of adaptive control to increase the system fidelity. Finally, such a system provides for ease of adjustment to new hardware, should future research require it.
journal_name
Ann Biomed Engjournal_title
Annals of biomedical engineeringauthors
Sunagawa K,Lim KO,Burkhoff D,Sagawa Kdoi
10.1007/BF02367387subject
Has Abstractpub_date
1982-01-01 00:00:00pages
145-59issue
4eissn
0090-6964issn
1573-9686journal_volume
10pub_type
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