Fig. 1

Cardio-Ankle Vascular Index and equation for estimating end diastolic volume (EDV). (A) Schematic drawing of a pressure-volume loop. PVA is the area obtained by adding A and (B) A: the approximately triangular area bound by the end systolic pressure volume relation, end diastolic pressure volume relation and left border of the pressure-volume loop. B: the area within the pressure-volume loop, expressed as EW.

B. (Adapted from ref. 1) Schematic diagram of a pressure-volume loop. Ees: slope of the end-systolic pressure-volume relationship, Ea: slope of the line connecting the end-diastolic volume (EDV) on the volume axis to the end-systolic pressure volume point. Pes: end-systolic pressure, Pad: diastolic pressure, Pmax: putative isovolumic pressure, E(t): change in the elastance of the left ventricle on standing, k: ratio of the slope when E(t) was approximated bilinearly in the isovolumic contraction phase and isovolumic ejection phase, PEP: pre-ejection period, ET: ejection time