In the Windkessel arterial model, which statement correctly pairs the elements with their functions?

• A. Capacitance stores arterial blood; Resistance controls peripheral resistance.
• B. Compliance stores arterial blood; Resistance controls peripheral resistance.
• C. Capacitance stores arterial blood; Compliance controls peripheral resistance.
• D. Resistance stores arterial blood; Capacitance controls peripheral resistance.

Answer: (B)

In the Windkessel model, the storage of blood as pressure rises is captured by a compliance element, which represents how much volume the artery can hold for a given pressure change. The flow then encounters resistance that represents the cumulative opposition of the peripheral vasculature. So the element that stores blood is the compliance, and the element that accounts for the systemic resistance is the resistor. The pairing that states compliance stores arterial blood and resistance represents peripheral resistance best captures this mapping. (Capacitance is the electrical analogue of storage, but the physiological term used for the storage property is compliance.)