Assessment of a parametric identification procedure of simple models for left ventricular afterload

Recently many studies have been devoted to the evaluation of the behaviour of the arterial system by calculating the left ventricular afterload, on the basis of the hydraulic impedance concept. Since the best known computation procedure, based on Fourier analysis, does not seem to be fully reliable, simple mathematical models have been set up by various investigators. One important problem is the choice of an identification procedure which points out the reliability of such models on the one hand, and which on the other hand allows us to compare them with each other. The behaviour of such a procedure can depend on operating conditions such as: (a) the choice of the input/output signals for the model (pressure or flow) and (b) the amount of noise and/or transient arterfacts added to these signals. Therefore, in the present work, the assessment of a parametric identification procedure has been studied relating to two different models previously proposed by the authors themselves, and its robustness has been evaluated in regard to the above mentioned conditions.