Which statement about preload is accurate?

• A. Venous Dilation reduces preload
• B. Venous Dilation increases preload
• C. Preload does not affect heart size
• D. Preload increases afterload

Answer: (A)

Preload is the amount of blood filling the ventricle at the end of diastole, reflecting venous return. When veins dilate, they become more capacious and hold more blood, so less blood returns to the heart. This decreases end-diastolic volume and pressure, lowering preload. So venous dilation reduces preload, which is why that statement is accurate. The other ideas don’t fit: increasing venous return would raise preload, not lower it; preload can influence heart size by changing end-diastolic volume, so saying it doesn’t affect heart size isn’t accurate; and preload is not the same as afterload, nor does it increase afterload.