An approach to estimate the nonlinearity in right ventricular dynamics

A method for estimation of nonlinearity in right ventricular dynamics employing the input-error approach is described. A basic electrical analog of the circulation dynamics is considered that is applicable only during linear operation in the cardiac performance interval. A feedback system describing the linear dynamics of the circulation process is developed. To make the system applicable to the entire cardiac cycle, a signal actuating the system is assumed to be present, in addition to the normal one, at the input side of the system. This gives rise to an input error in the developed linear model of the system dynamics. This input error, which accounts for the nonlinearity involved in the circulation dynamics, is determined. Use of the knowledge of the determined input error in estimating the nonlinearity involved in the right ventricular process parameters is indicated.