Which condition increases afterload?

Which condition increases afterload?

• A. Increased arterial pressure.
• B. Increased venous return.
• C. Increased heart rate.
• D. Decreased arterial pressure.

Answer: (A)

Afterload is the pressure the ventricle must overcome to eject blood during systole. When arterial pressure in the aorta and systemic circulation rises, the left ventricle has to generate a higher pressure to open the aortic valve and push blood forward, which directly increases afterload. This makes the heart work harder to eject blood and can limit stroke volume if contractility doesn’t compensate. Increased venous return raises preload (the filling pressure) but doesn’t directly raise afterload; heart rate changes affect cardiac output and myocardial oxygen demand but are not the primary determinant of afterload; decreased arterial pressure lowers the pressure the heart must overcome, reducing afterload. Therefore, higher arterial pressure increases afterload.

Afterload is the pressure the ventricle must overcome to eject blood during systole. When arterial pressure in the aorta and systemic circulation rises, the left ventricle has to generate a higher pressure to open the aortic valve and push blood forward, which directly increases afterload. This makes the heart work harder to eject blood and can limit stroke volume if contractility doesn’t compensate. Increased venous return raises preload (the filling pressure) but doesn’t directly raise afterload; heart rate changes affect cardiac output and myocardial oxygen demand but are not the primary determinant of afterload; decreased arterial pressure lowers the pressure the heart must overcome, reducing afterload. Therefore, higher arterial pressure increases afterload.