What is the normal mean pulmonary artery pressure at rest?

What is the normal mean pulmonary artery pressure at rest?

• A. 20-25 mmHg
• B. 5-9 mmHg
• C. 10-14 mmHg
• D. 15-20 mmHg

Answer: (C)

Normal mean pulmonary artery pressure at rest is around 10–14 mmHg. This small rise reflects the pulmonary circulation’s low resistance and high compliance, so the right heart can pump the normal cardiac output without a large pressure increase. A handy way to think about it is that mPAP is roughly the product of pulmonary vascular resistance and cardiac output, plus the left atrial pressure; with resting CO about 5 L/min, PVR low, and the left atrial pressure only a few mmHg, you land in the ~10–14 mmHg range. Pressures well above this, such as 15–20 or 20–25 mmHg, would be considered abnormal and suggest pulmonary hypertension.

Normal mean pulmonary artery pressure at rest is around 10–14 mmHg. This small rise reflects the pulmonary circulation’s low resistance and high compliance, so the right heart can pump the normal cardiac output without a large pressure increase. A handy way to think about it is that mPAP is roughly the product of pulmonary vascular resistance and cardiac output, plus the left atrial pressure; with resting CO about 5 L/min, PVR low, and the left atrial pressure only a few mmHg, you land in the ~10–14 mmHg range. Pressures well above this, such as 15–20 or 20–25 mmHg, would be considered abnormal and suggest pulmonary hypertension.