Record Display for the EPA National Library Catalog

RECORD NUMBER: 44 OF 908

OLS Field Name OLS Field Data
Main Title Analog Echocardiogram for Estimating Ventricular Stroke Volume.
Author Petrovick, M. L. ; Malindzak, Jr., G. S. ; Haak, Jr., E. D. ;
CORP Author Health Effects Research Lab., Research Triangle Park, N.C.
Year Published 1976
Report Number EPA/600/J-76/066;
Stock Number PB-268 120
Additional Subjects Heart function tests ; Cardiography ; Medical equipment ; Ultrasonic frequencies ; Biomedical measurement ; Feasibility studies ; Signal processing ; Analog systems ; Reprints ; Echocardiography ; Cardiac output ; Noninvasive tests ; Signal processing systems ; Image processing
Holdings
Library Call Number Additional Info Location Last
Modified
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Status
NTIS  PB-268 120 Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy. NTIS 06/23/1988
Collation 11p
Abstract
A multiple range-gated echocardiographic signal processor has been developed for the purpose of converting the complex ultrasonic image of the left ventricular anterior and posterior wall boundaries to equivalent analog signals as a means of estimating stroke volume and computing cardiac output. Two conventional time-analog range-gated modules have been redesigned and synchronized with the initial transmit pulse of 1000 hz, for the purpose of simultaneously gating echocardiographic images of the anterior and posterior left ventricular walls. Each echocardiographic image boundary is selectively gated in the A-Mode and adjusted to a width exceeding the maximum wall motion. The gated echocardiographic boundary of each time-analog channel is processed by a fast-attack envelope detector and a low-pass filter network to produce a D.C. analog signal corresponding to the motion of the left ventricular anterior and posterior wall. These analog signals serve as the basis for the estimation of ventricular stroke volume and the computation of cardiac output.