Background; We previously proposed that the analysis of tissue velocity with negative strain was useful for quantification of longitudinal contractility in failing heart. This study aimed to evaluate whether the baseline longitudinal strain by 2D-speckle tracking (2DL) can predict contractile reserve (CRV) and overcome the limitation of Doppler strain (DOL) method. Methods: Supine bicycle exercise was performed in 31 patients with non-ischemic cardiomyopathy (51 짹 12 years, EF <40%). In 6 LV segments on apical 4 chamber view, the peak systolic velocities were measured at baseline and peak exercise (Vb, Vp) by tissue Doppler image (TDI). ∆V was calculated as [Vp-Vb], representing CRV. At baseline, DOL and 2DL of 6 LV segments were respectively obtained. Results: With exercise (9.7 짹 2.4 min.), myocardial velocities of 186 LV segments increased from 3.1 짹 1.3 cm/s (Vb) to 4.4 짹 1.6 cm/s (Vp). The 41 patients with Vb��� 3 cm/s and 2DL > -10 % (reduced negative strain, group C) showed much lower ∆V, compared 57 patients with Vb ��� 3 cm/s and 2DL < -10 % (group D), (0.8 짹 0.9 vs 1.7 짹 1.0 cm/s, p<0.001, fig 2). The baseline 2DL showed significant correlation with ∆V (r=-0.326, p<0.001, fig 1) and also with Vp (r=-0.188, p=0.010). Although DOL correlated with 2DL (r=0.305, p<0.001), there was no correlation between DOL and ∆V (p=0.090) or between Vb and ∆V (p=0.358). Conclusion: The baseline 2DL was a powerful index reflecting the CRV (∆V) during exercise in patients with non-ischemic cardiomyopathy.