Figure 1.

(a) Arterial-ventricular interaction model. The arterial system is modeled by a three-element windkessel model, consisting of characteristic impedance (Z ₀), peripheral vascular resistance (R _p) and arterial compliance (C _a). The heart is modeled using a time-varying elastance model, with elastance function constructed using a normalized elastance curve18 as depicted in (b). A pressure–volume loop with the major ventricular parameters is shown in (c). Examples of simulated pulmonary artery pressure P _a(t) and right ventricular pressure P _RV(t) are shown in (d). E _es = end-systolic elastance; E _ed = end-diastolic elastance; V ₀ = intercept volume; P _v = venous filling pressure; R _v = venous resistance; t _es = time to reach end-systolic elastance; t _ed = time to reach end-diastolic elastance; V _s = stroke volume; P _max = maximum isovolumic pressure