Optimizing Doppler Assessment of Aortic Stenosis in Atrial Fibrillation: Role of the Highest Mean Gradient and Peak Velocity

The coexistence of atrial fibrillation (AF) and aortic stenosis (AS) complicates echocardiographic assessment, as AF-related beat-to-beat variability attenuates flow-dependent Doppler parameters like transvalvular mean gradient (MG) and Peak Velocity. Current guidelines recommend averaging these measurements over 5 consecutive cycles in AF; however, this may underestimate true AS severity. In this retrospective study of 35 patients with AS and preserved (left ventricular ejection fraction ≥50%) undergoing echocardiography in both AF and sinus rhythm (SR) within a 3-month interval, averaged MG during AF was significantly lower than SR (19 vs 21 mm Hg; p <0.001) with lower agreement (ICC = 0.866), whereas the highest single-cycle MG closely approximated SR values (21 vs 20 mm Hg; p = 0.741) with excellent agreement (ICC = 0.953). A similar pattern was observed for peak velocity. These findings suggest that averaged AF gradients and velocities may underrecognize significant AS severity, and that the highest technically adequate AF values may better reflect true hemodynamic burden, warranting prospective validation.