What is end-systolic volume (ESV)?

What is end-systolic volume (ESV)?

• A. The blood remaining in a ventricle at the end of systole.
• B. The amount of blood pumped out during systole.
• C. The volume in the ventricle at the end of diastole.
• D. The amount of blood in the aorta.

Answer: (A)

End-systolic volume is the amount of blood left in the ventricle when the heart has finished contracting (at the end of systole). It reflects how much blood remains after the ventricle has ejected as much as it can during that beat. This is different from stroke volume, which is the amount ejected during systole and is calculated as EDV minus ESV. It’s also different from end-diastolic volume, which is the maximal ventricular volume right before contraction, and from the amount of blood in the aorta, which is not a direct measure of ventricular residual volume. If contractility is reduced or afterload is high, more blood stays in the ventricle at the end of systole, increasing ESV and lowering stroke volume.

End-systolic volume is the amount of blood left in the ventricle when the heart has finished contracting (at the end of systole). It reflects how much blood remains after the ventricle has ejected as much as it can during that beat. This is different from stroke volume, which is the amount ejected during systole and is calculated as EDV minus ESV. It’s also different from end-diastolic volume, which is the maximal ventricular volume right before contraction, and from the amount of blood in the aorta, which is not a direct measure of ventricular residual volume. If contractility is reduced or afterload is high, more blood stays in the ventricle at the end of systole, increasing ESV and lowering stroke volume.