An elevated PAWP is most indicative of which condition?

• A. Left-sided heart failure
• B. Hypovolemic shock
• C. Septic shock
• D. Anaphylactic shock

Answer: (A)

Pulmonary artery wedge pressure reflects the pressure in the left atrium and, by extension, the left-sided filling pressures. When the left heart isn’t pumping effectively, pressure backs up into the pulmonary veins and capillaries, raising the wedge pressure. That elevated PAWP is a hallmark of left-sided heart failure with pulmonary congestion.

In contrast, hypovolemic shock involves low preload from insufficient circulating volume, so PAWP tends to be low. Septic and anaphylactic shocks are distributive, with vasodilation and relative intravascular volume loss, giving normal or low filling pressures rather than elevated wedge pressures. So an elevated PAWP most strongly points to left-sided heart failure.