Calculation of parameters of end-systolic pressure–volume relation in the ventricles

The slope and intercept of a non-linear model of the end-systolic pressure–volume relation (ESPVR) are calculated by using a previously derived mathematical formalism describing the pressure–volume relation (PVR) in the left ventricle. An important feature of this mathematical approach is the inclusion of the peak isovolumic pressure PisomPisom in the formalism describing the PVR in the left ventricle. The mathematical procedure used in this study is simple and can be easily implemented in a non-invasive way for clinical applications; only the ventricular pressure PmPm near end-systole needs to be estimated.