Abstract: Objective · To evaluate the strain parameters measuredtwo-dimensional speckle tracking echocardiography (2D-STE) in predicting myocardial segment functional recovery and left ventricular (LV) remodeling. Methods · Eighty-one patients with first acute ST-elevation myocardial infarction were enrolled. All patients underwent cardiac magnetic resonance (CMR) within 8 days after reperfusion therapy to detect the percentage of necrotic myocardium and the presence of microvascular obstruction or intra myocardial hemorrhage. Echocardiography examination for the first time was performed on the same day as CMR. Segmental and global circumferential strain (CS), radial strain, and longitudinal strain were measured2D-STE. Echocardiography was performed again after an average follow-up of 14 months. Results · The segments with functional recovery were associated with higher absolute values of strain parameters at baseline compared to those without functional recovery. The receiver operating characteristic (ROC) curve analysis showed that the sensitivity and specificity of CS ≤ -7.77% to predict the functional recovery of myocardial segment were 77.17% and 61.40%, respectively (AUC0.74, P0.000). Multiple Logistic regression showed that the percentage of necrotic myocardium and global CS (GCS) were the powerful predictors of LV remodeling (P<0.05). According to ROC curve analysis, GCS ≥ -17.48% had sensitivity of 88.33% and specificity of 69.23%（AUC0.80，P0.000） in predicting LV remodeling. Conclusion · Among the strain parameters of 2D-STE, CS may be an ideal predictor of segment functional recovery and LV remodeling after myocardial infarction.

Key words: two-dimensional speckle tracking echocardiography (2D-STE), acute myocardial infarction, prognosis, left ventricular remodeling, cardiac magnetic resonance (CMR)