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Updated: Jun 10, 2026
Noninvasive Determination of Vortex Formation Time Using Transesophageal Echocardiography During Cardiac Surgery
Published on: November 28, 2018
The estimation of the cardiac time-varying parameters during the ejection phase of the cardiac cycle using the Ito
1MIT/Lincoln Lab, Lexington, MA, USA. ataleb@mcit.gov.eg
Abstract:
Evaluation of the time-varying parameters (Compliance, Resistance, and Inertance) that describe the right and left ventricles has been of interest for some years. Analyses usually involve a particular assertion regarding energy contributions or of the nature of the parameters themselves. It is of interest to engage the issue with a more general approach by restricting prior assumptions only to that raw data measurement may be noisy and that the parameters are non negative. Here a polynomial in time model is utilized to develop each parameter. Coefficients of the polynomials are estimated from the observed data with use of the maximum likelihood method and stochastic calculus. The pump equation was finally evaluated in full from un-processed pressure and flow data and the method is provided herein.
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