The volume of blood in the ventricle at end diastole is defined as which of the following?

The volume of blood in the ventricle at end diastole is defined as which of the following?

• A. End diastolic volume
• B. End systolic volume
• C. Stroke volume
• D. Cardiac output

Answer: (A)

End-diastolic volume is the amount of blood in the ventricle at the end of the filling phase, right before the heart muscle contracts. This captures the preload—the initial stretch of the ventricular muscle—and helps determine how much blood will be ejected with the next heartbeat (more filling increases SV via the Frank-Starling mechanism). The remaining blood after contraction is end-systolic volume, and the amount ejected per beat is stroke volume (EDV minus ESV). Cardiac output is the product of stroke volume and heart rate.

End-diastolic volume is the amount of blood in the ventricle at the end of the filling phase, right before the heart muscle contracts. This captures the preload—the initial stretch of the ventricular muscle—and helps determine how much blood will be ejected with the next heartbeat (more filling increases SV via the Frank-Starling mechanism). The remaining blood after contraction is end-systolic volume, and the amount ejected per beat is stroke volume (EDV minus ESV). Cardiac output is the product of stroke volume and heart rate.