What is the effect of aortic stenosis on Mean Arterial Pressure (MAP)?

In aortic stenosis, the narrowing of the aortic valve leads to an increase in left ventricular pressure as the heart works harder to eject blood through the narrowed opening during systole. This increased pressure can initially lead to an increase in systolic blood pressure due to the compensatory mechanisms of the heart. However, as the disease progresses, the heart may become less efficient, resulting in a decrease in stroke volume and cardiac output.

Mean Arterial Pressure (MAP) is influenced by both cardiac output and systemic vascular resistance. In the case of aortic stenosis, although peripheral resistance may increase due to compensatory mechanisms, the significant reduction in stroke volume due to the ineffective ejection of blood through the narrowed valve results in a decrease in overall cardiac output. As a result, this reduced cardiac output contributes to a lower MAP.

MAP is calculated using the formula: MAP = DBP + (1/3)(SBP - DBP). In patients with aortic stenosis, the combined effects of reduced stroke volume and potential diastolic dysfunction lead to a scenario where MAP may fall below normal levels, particularly in severe cases, hence leading to its decreased values.

In essence, the primary effect of aortic stenosis on Mean Arter