Stroke volume refers to which of the following descriptions?

Stroke volume specifically refers to the volume of blood that is ejected from the heart with each contraction, or heartbeat. This measurement is critical in assessing the efficiency of the heart's pumping ability and is a key parameter in understanding cardiac function. Stroke volume is typically calculated as the difference between the end-diastolic volume (the volume of blood in the ventricles before contraction) and the end-systolic volume (the volume remaining in the ventricles after contraction). This concept is fundamental in the analysis of cardiac performance, as it reflects how much blood the heart delivers to the circulation during each cycle.

In contrast, the other descriptions provided relate to different aspects of cardiac function or blood volume but do not accurately define stroke volume. The volume of blood in the ventricle at the end of diastole pertains to preload, total blood volume in the body refers to overall blood volume rather than the volume per heartbeat, and blood volume returning to the heart is related to venous return, which influences stroke volume but is not the definition itself. Understanding stroke volume is essential for evaluating cardiac output and recognizing heart health.