What is ‘stroke volume’?

Stroke volume refers to the amount of blood pumped out of the heart with each heartbeat. It is a measure of the volume of blood ejected from the left ventricle of the heart during systole, which is the contraction phase of the cardiac cycle.

To calculate stroke volume, you need to know the end-diastolic volume (EDV) and the end-systolic volume (ESV). The EDV is the volume of blood in the ventricle at the end of diastole, when the ventricle is relaxed and filled with blood. The ESV is the volume of blood in the ventricle at the end of systole, when the ventricle has contracted and ejected blood.

The formula to calculate stroke volume is:

Stroke Volume = EDV - ESV

By subtracting the ESV from the EDV, you can determine the amount of blood that was ejected from the ventricle during systole. This value represents the stroke volume.

Stroke volume is an important parameter in assessing cardiac function. It can be influenced by factors such as heart rate, contractility of the heart muscle, and preload (the amount of blood returning to the heart). Changes in stroke volume can indicate abnormalities in cardiac function and can be used to diagnose and monitor conditions such as heart failure or valvular heart disease.