19. LV volume: The intraventricular volume at the end of systole in termed the end-systolic volume (ESV). Under resting conditions ESV is about 65 ml.

The difference between the EDV and the ESV is defined as stroke volume (SV = EDV-ESV). The proportion of the left ventricular volume which is expelled with each beat is the ejection fraction (EF). EF = (SV ) EDV) x 100%