Modeling and System Identification of Arterial Hemodynamics in Humans

This paper seeks to determine the validity of two distinct tube-load models relating central aortic blood pressure to peripheral blood pressure in humans. Specifically a single-tube model (1-TL) and a serially connected two-tube (2-TL) model, both terminating in a Windkessel load, are considered as representations of the central aortic-peripheral arterial path. The validity and fidelity of the two models was assessed and compared quantitatively by fitting central aortic, radial and femoral blood pressures collected from 8 patients. Both models fitted the BP waveform pairs effectively, and were capable of estimating pulse travel time (PTT) accurately; also the model derived frequency responses were close to the empiric transfer function estimates derived from central and peripheral BP measurements. The 2-TL model was consistently better than 1-TL with statistical significance in terms of accuracy of the central aortic BP waveform, the average waveform RMSE were 2.52 mmHg versus 3.24 mmHg respectively (p<0.05).