In contrast, hypovolemia resulting from a loss of blood volume (e.g., hemorrhage) leads to less ventricular filling and therefore shorter sacromere lengths (reduced preload). Changes in ventricular preload dramatically affect ventricular stroke volume by what is called the Frank-Starling mechanism.

What causes increased stroke volume?

Stroke volume increases primarily as a result of the simultaneous decrease in afterload resistance on the heart and the increase in left-ventricular preload.

Does stroke volume increase with blood loss?

The fall in cardiac output and heart stroke volume after blood loss were more pronounced when the ICP was high, and the increase in systemic vascular resistance was considerably greater.