Decreased afterload has what effect on the left ventricle?

• A. LV works worse
• B. LV works better
• C. No change
• D. LV end-systolic pressure decreases

Answer: (B)

Afterload is the resistance the left ventricle must overcome to eject blood. When this resistance decreases, the ventricle can push blood into the aorta with less pressure, so it doesn’t have to work as hard. As a result, stroke volume increases (assuming preload and contractility stay the same) and the heart operates more efficiently. The overall effect is improved LV performance because the ventricle is able to eject blood more easily, reducing wall stress and oxygen demand. While the end-systolic pressure may fall as part of this easier ejection, the key takeaway is that the left ventricle works better when afterload is reduced.