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Figure 8 Schematic diagram demonstrating the concept that inertia force of late systolic aortic flow enhances left ventricular (LV) elastic recoil. (A) Left ventricles with relatively better LV systolic function give inertia to the late systolic aortic flow. In late systole, when LV muscle shortening has reached a limit but its tension-bearing ability is still maintained, the inertia of the blood flowing out of the LV causes swift end-systolic unloading of the LV, producing additional LV muscle shortening and hence smaller LV end-systolic volume. The resulting greater elastic recoil force brings faster LV relaxation. (B) Left ventricles with impaired contractile function do not give inertia to the late systolic aortic flow. Hence, the swift LV end-systolic unloading caused by the inertia force does not occur. LV relaxation is slow because of the lack of LV elastic recoil.