Final answer:
When the aortic pressure is altered, it affects the afterload and cardiac performance. Afterload refers to the tension that the ventricles must develop to pump blood effectively against the resistance in the vascular system. A decrease in resistance reduces afterload, while an increase in resistance increases afterload.
Step-by-step explanation:
When the aortic pressure is altered, it affects the afterload and cardiac performance. Afterload refers to the tension that the ventricles must develop to pump blood effectively against the resistance in the vascular system. A decrease in resistance reduces afterload, while an increase in resistance increases afterload. If afterload increases and cardiac function does not compensate, blood flow may actually decrease. On the other hand, if afterload decreases, blood flow may increase.