MS will cause an increase in:

MS will cause an increase in:

• A. Stroke Volume
• B. Cardiac Output
• C. Heart Rate
• D. Systemic Vascular Resistance

Answer: (C)

Mitral stenosis reduces the preload to the left ventricle by obstructing flow from the left atrium, so stroke volume tends to fall. To keep cardiac output up, the body compensates by increasing heart rate. Since cardiac output is the product of heart rate and stroke volume, boosting heart rate helps offset the reduced stroke volume, even though the heart’s pumping efficiency is still limited. Systemic vascular resistance isn’t directly driven higher by mitral stenosis, and stroke volume would not be increased by this lesion. Atrial enlargement in MS often leads to atrial arrhythmias like atrial fibrillation, which can further raise heart rate and worsen filling, reinforcing the compensatory tachycardia.

Mitral stenosis reduces the preload to the left ventricle by obstructing flow from the left atrium, so stroke volume tends to fall. To keep cardiac output up, the body compensates by increasing heart rate. Since cardiac output is the product of heart rate and stroke volume, boosting heart rate helps offset the reduced stroke volume, even though the heart’s pumping efficiency is still limited. Systemic vascular resistance isn’t directly driven higher by mitral stenosis, and stroke volume would not be increased by this lesion. Atrial enlargement in MS often leads to atrial arrhythmias like atrial fibrillation, which can further raise heart rate and worsen filling, reinforcing the compensatory tachycardia.