Structured tree outflow condition for blood flow in larger systemic arteries.
A central problem in modeling blood flow and pressure in the larger systemic arteries is determining a physiologically based boundary condition so that the arterial tree can be truncated after a few generations. We have used a structured tree attached to the terminal branches of the truncated arterial tree in which the root impedance is estimated using a semianalytical approach based on a linearization of the viscous axisymmetric Navier-Stokes equations. This provides a dynamic boundary condition that maintains the phase lag between blood flow and pressure as well as the high-frequency oscillations present in the impedance spectra. Furthermore, it accommodates the wave propagation effects for the entire systemic arterial tree. The result is a model that is physiologically adequate as well as computationally feasible. For validation, we have compared the structured tree model with a pure resistance and a windkessel model as well as with measured data.
Olufsen
M S
MS
Math-Tech and Department of Mathematics, Roskilde University, Roskilde 4000, Denmark.
D001158:Arteries / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology; D006801:Humans; D008955:Models, Cardiovascular; D011673:Pulsatile Flow; D012039:Regional Blood Flow / Q000502:physiology; D014655:Vascular Resistance / Q000502:physiology