endsystolic

End-systolic is an anatomical and physiological term used to describe the moment at the end of systole, the phase of the heartbeat when the ventricles have completed contraction and begin to relax. It is commonly applied to measurements that capture the heart’s state at that exact point, such as end-systolic volume, end-systolic pressure, and end-systolic dimensions.

End-systolic volume (ESV) is the amount of blood remaining in the ventricle at the end of systole. ESV is influenced by preload, afterload, and contractility. In healthy adults at rest, left ventricular ESV typically falls in the range of about 40 to 60 milliliters, though values vary with body size and cardiac condition. ESV, along with end-diastolic volume (EDV), determines stroke volume and the ejection fraction (EF = SV/EDV).

End-systolic pressure refers to the pressure within the ventricle at the end of systole. In the left ventricle, end-systolic pressure is closely related to the aortic systolic pressure, but a small gradient can exist during ejection. Clinically, ESP can be measured directly via invasive methods or estimated using imaging-based approaches.

The end-systolic pressure-volume relationship (ESPVR) describes how end-systolic pressure varies with end-systolic volume. Its slope, known as end-systolic elastance (Ees), is a key indicator of contractility: higher Ees suggests stronger cardiac contraction. The ESPVR is a useful concept in invasive hemodynamic assessment and cardiac mechanics research; its intercept (V0) is a theoretical volume at zero pressure and is of mainly theoretical interest.

Evidence-based assessment of end-systolic metrics relies on imaging (echocardiography, MRI) and, when needed, invasive hemodynamic monitoring. In clinical practice, end-systolic measures help evaluate heart function, effects of therapies, and conditions such as heart failure.