A Single-Beat Estimation Method for Emax Directly Based on Linearity of Ventricular Elastance

This paper has derived a new method for estimating the maximum ventricular elastance Emax by assuming that the following two assumptions are simultaneously established in a certain part of the ejection period: the ventricular elastance E(t) changes linearly with time and the dead volume V0 does not change. The method can estimate Emax in a single beat without any change in the cardiac load by measuring the ventricular pressure and either the ventricular volume or outflow. The method does not need to previously assign the approximation range of E(t) and does not include the recursive procedure to search for the peak time tmax that gives Emax. In an experiment in vivo, it could be ascertained that the method can derive the estimate of Emax roughly close to the true value.