Stress Echocardiography Evaluation of Paradoxical Low-Flow Aortic Stenosis

Dobutamine stress echocardiography (DSE) is a well-established test for helping to differentiate true from pseudo aortic stenosis (AS) in patients with a low transvalvular gradient related to poor left-ventricular ejection fraction (LVEF). However, stress testing has not been evaluated in AS patients who have paradoxical low LV flow — i.e., with restrictive physiology but preserved LVEF.

Now, researchers have prospectively assessed the value of stress echocardiography in 55 patients with severe AS (valve area, ≤1.0 cm²), a low mean gradient (≤40 mm Hg), preserved LVEF (>50%), and low LV flow (stroke volume index, ≤35 mL/m²). Of the 55 patients, 37 underwent exercise stress echocardiography, and 18 underwent DSE.

During a mean follow-up of 1.5…