A decrease in the EDV would be the result of which of the following scenarios?

A decrease in end-diastolic volume (EDV) is associated with several physiological changes, and one scenario that can lead to this is a distal arterial obstruction. When there is an obstruction downstream in the arterial system, the normal flow of blood is impeded. This can result in reduced venous return, as blood may struggle to flow back to the heart due to increased resistance. A decrease in venous return leads to a reduced volume of blood in the ventricles at the end of diastole, ultimately lowering the EDV.

In contrast, increased arterial compliance allows the arteries to accommodate larger volumes of blood, which could potentially keep EDV stable or increase it. An increased heart rate can lead to insufficient time for the ventricles to fill, potentially reducing EDV but is generally more complex, as it depends on other factors such as stroke volume. Vasodilation generally facilitates increased blood flow, potentially enhancing venous return and maintaining or increasing EDV.

Thus, distal arterial obstruction is a clear contributor to a reduction in EDV through its effect on blood flow and venous return dynamics.