Automated function imaging (AFI) is a novel algorithm based on speckle-tracking imaging that can be used for assessment of global longitudinal strain of the left ventricle. However, there is limited data about clinical impacts on serial assessment of left ventricle longitudinal strain in patients with acute myocardial infarction (AMI) after revascularization. Methods: The study population consisted of 114 consecutive patients with first AMI. The global longitudinal peak systolic strain average (GLPSS Avg) was obtained by AFI. The GLPSS Avg was performed at initial presentation, and 3 days after coronary intervention. The change of GLPSS Avg was defined as unchanged (between -15% and 15%, Group 1), improved (increase more than 15%, Group 2), or worsened (decrease more than 15%, Group 3). Subsequent complications including cardiac death, shock, congestive heart failure were prospectively evaluated during 6 months. Results: GLPSS Avg after revascularization was unchanged in 81 patients (71 %), improved in 20 patients (18 %), and worsened in 13 patients (11 %). Group 3 showed more infarct size estimated by serial CK-MB measurement (figure). NT-proBNP level was significantly increased Group 3 (Group 1 = 585 짹 216, Group 2 = 265 짹 186, group 3 = 1087 짹 346, p <0.001). Complications were developed in 22 patients (Group 1 = 12 (10%), Group 2 = 0 (0%), Group 3 = 10 (77%), p <0.001). Conclusion: In patients with AMI, serial GLPSS Avg assessment in acute phase could be simple and noninvasive method to predict the infarct size and subsequent complications.