What effect does aortic stenosis typically have on cardiac output?

In aortic stenosis, the narrowing of the aortic valve leads to an obstruction of blood flow from the left ventricle to the aorta during systole. This restriction increases the pressure load on the left ventricle, as it must work harder to pump blood through the narrowed valve. As a result, over time, the left ventricle undergoes hypertrophy to compensate for this increased workload.

However, as the disease progresses and the severity of the stenosis increases, the heart's ability to maintain cardiac output diminishes. The narrowed valve limits the volume of blood that can be ejected during each heartbeat, particularly during activities that demand an increased cardiac output such as exercise. Consequently, the overall cardiac output falls due to this impaired ventricular ejection and the inability of the heart to respond appropriately to increased physical demands.

Therefore, aortic stenosis typically leads to a decreased cardiac output, which aligns with the correct response. It's important to monitor patients with this condition, as they may experience symptoms of heart failure or reduced exercise tolerance as their cardiac output becomes compromised.