Abstract Background: Aortic valve stenosis (AS) commonly causes left ventricular (LV) pressure overload; thus, identifying patients with adverse remodeling/early LV dysfunction is critical. We compared 2-dimensional (2D) to 3-dimensional (3D) echocardiographic measures of LV myocardial deformation in patients with severe AS and studied the relation of LV preload and afterload (Zva) to myocardial deformation. Methods: We prospectively included 168 symptomatic patients (72±12 years) with severe AS and ejection fractions ≥50%. Strain parameters from those patients were compared with normal values found in the literature. 3D full-volume and 2D images were analyzed for global longitudinal strain (GLS), global radial strain (GRS), global circumferential strain (GCS), systolic strain rate (SRs), basal rotation (Rotmax-B), apical rotation (Rotmax-A), and peak systolic twist (Twistmax). Results: 2D–GLS and 2D–GCS decreased significantly compared with normal values (P˂.001 and P=.02, respectively); 2D Rotmax-B and Twistmax increased (P˂.001 vs normal values). Agreement between 2D–GLS and 3D–GLS by concordance correlation coefficient was 0.49 (95% CI, 0.39-0.57) in patients with AS. Both 2D– and 3D–GLS correlated with valvulo-arterial impedance (Zva) (r=0.34, P<.001; and r=0.23, P=.003, respectively). Conclusion: In patients with severe AS, GLS and GCS decreased, and basal rotation and twist increased to maintain LV ejection fraction. 2D– and 3D–GLS had a relatively fair agreement. Both 2D– and 3D–GLS correlated modestly with Zva.