How does increased afterload generally affect stroke volume?

Increased afterload refers to the pressure that the heart must work against to eject blood during systole. When afterload rises, the heart faces greater resistance in the arterial system. This increased workload can lead to a reduction in stroke volume, which is the amount of blood the heart pumps with each beat.

The heart compensates for this increased afterload by contracting more forcefully, but if the afterload is excessively high, the heart may not be able to generate enough force to overcome this resistance. Consequently, the volume of blood ejected during each heartbeat decreases, resulting in a lower stroke volume.

This physiological response is significant because it illustrates the relationship between cardiac function and vascular resistance. Higher afterload can be a consequence of conditions such as hypertension or aortic stenosis, which can lead to decreased overall cardiac output if not compensated adequately.