Background: Functional recovery after revascularization depends on the viability of myocardium. Therefore the identification of viable myocardium for patients with chronic ischemic heart disease has been a challenging diagnostic step. Recently, 2D speckle tracking imaging (STE) allows accurate assessment of regional myocardial function. The aim of study was to evaluate the feasibility of myocardial deformation imaging using STE for prediction of functional recovery after surgical revascularization. Methods: Between February 2007 and December 2008, 75 consecutive patients (60짹7years, 40 men) with regional wall motion abnormalities (RWMA) caused by triple vessel disease were prospectively enrolled. All patients underwent coronary artery bypass surgery. Baseline echocardiography at rest was performed before surgical revascularization, and follow-up echocardiography was done at 8짹2 month for assessment of functional recovery. Apical 16 segment model and wall motion score from 1(normal) to 3 (akinesia) were used. In each 16 segment model, longitudinal peak systolic strain and its corresponding transverse strain were measured. Additionally, the presence of post-systolic shortening (PSS) was assessed. Segments were considered to demonstrate functional recovery during follow-up if it improved by at least 1 grade Result: Total 211 segments with RWMA were classified by the presence of functional recovery (98: viable, group A vs. 113 : non-viable, group B). There was no difference in longitudinal peak strain between the two group (-7.4짹6.1 vs. -8.2짹5.6%, p=0.58), and the prevalence and magnitude of longitudinal PSS was not different between A and B (74% vs. 65%, P=0.12; -10.8 vs. -11.5, p=0.33, respectively). In contrast, peak systolic transverse strain was higher in functionally recovered group A (15.3짹12.3 vs. 7.0짹8.6%, p<0.001). Furthermore, transverse PSS was more prevalent in group A than B (57% vs. 46, p=0.03), and the magnitude of PSS was significantly higher in group A (22.4짹10.1 vs. 14.5짹10.2%, p<0.001). Using a cutoff of 10% for peak systolic transverse strain, functional recovery could be predicted with good accuracy (sensitivity 68%, specificity 82%, area under the curve 0.80) Conclusion: Not longitudinal strain, but transverse strain assessed by STE can be a useful tool for identification of viable myocardium before revascularization, because it can be measurable in all segments of LV compared with radial and circumferential strain.