Stroke volume is calculated by subtracting the end-systolic volume (ESV) from the end-diastolic volume (EDV).
Here's a breakdown:
-
Stroke Volume (SV): The amount of blood ejected from the left ventricle (or right ventricle, though often referring to the left) with each heartbeat. It represents the difference between the maximum and minimum volume of blood in the ventricle during a single cardiac cycle.
-
End-Diastolic Volume (EDV): The volume of blood in the ventricle at the end of diastole (when the ventricle is filled). This is the maximum volume of blood in the ventricle during the cardiac cycle.
-
End-Systolic Volume (ESV): The volume of blood remaining in the ventricle at the end of systole (after the ventricle has contracted and ejected blood). This is the minimum volume of blood in the ventricle during the cardiac cycle.
The formula for calculating stroke volume is:
SV = EDV - ESV
Example:
Let's say:
- End-Diastolic Volume (EDV) = 120 mL
- End-Systolic Volume (ESV) = 50 mL
Then, Stroke Volume (SV) = 120 mL - 50 mL = 70 mL
Therefore, in this example, the stroke volume is 70 mL. This means that the ventricle ejects 70 mL of blood with each heartbeat.
