Figure 1

Five-Compartment Heart Model. Panel A shows the five-compartment heart model. An elastic pericardium encloses all four heart chambers. The dotted lines represent septal position when relaxed. Panel B is the equivalent hydraulic circuit model. Anatomical components of the equivalent circuit (LV = left ventricle, RV = right ventricle, LA = left atrium, RA = right atrium, SPT = interventricular septum, PERI = pericardium, TCV = tricuspid valve, MV = mitral valve, AOV = aortic valve, PAV = pulmonary valve). Specific pressures (P_PL = pleural pressure, P_PA = pulmonary arterial pressure, P_AO = aortic pressure, P_PERI = pericardial pressure, P_RA = right atrial pressure, P_LA = left atrial pressure, P_RV = right ventricular pressure, P_LV = left ventricular pressure).