Figure 3: Schematic representation of three element model. Za - characteristic impedance of proximal aorta, Ca - compliance of arterial system, R - total systemic peripheral resistance, Q(t) - blood flow as a function of time, P(t) - arterial pressure waveform, P(w) - windkessel pressure. Taken from ref. 73 (J. Appl. Physiol, 1993; 74: 2566-2573, The American Physiological Society) with permission.