Background: We assessed the relation between myocardial deformation and reverse remodeling to eliminate the potential mechanism that accounts for left ventricular (LV) improvement in patients with non-ischemic dilated cardiomyopathy. Methods: 25 consecutive patients with non-ischemic dilated cardiomyopathy (age 60짹15 years, 60% male, LVEF 33짹9%) were enrolled. We utilized 2D and 3D speckle tracking (Artida^TM, Toshiba) to assess the influence of multidirectional myocardial deformity on LV reverse remodeling. Global longitudinal, radial, circumferential strains by 2D speckle tracking as well as area strain by 3D wall motion tracking were measured and the relation between multidirectional strains and reverse remodeling was examined. Results: Six patients (24%) showed reverse remodeling during follow-up, defined by ���15% decrease in LV end-systolic volume. Patients showing reverse remodeling had comparable LV volumes, LV ejection fraction, E/E���, global longitudinal, circumferential, and radial strains and area strain to patients without reverse remodeling. However, among patients with LVEF ���35% (n=16), patients with reverse remodeling tended to have higher global circumferential strain than patients without reverse remodeling (Table 1). Conclusion: Global circumferential strain tended to relate to reverse remodeling in patients with dilated cardiomyopathy of LVEF ���35%, suggesting that preserved circumferential function might serve to restrain ventricular enlargement in this population.