Abstract 716: Global Left Ventricular Longitudinal Strain Assessed with Automated Function Imaging after Acute Myocardial Infarction Reflects Infarct Size and Predicts Long-Term Recovery of Left Ventricular Function
Automated Function Imaging (AFI) provides a new imaging modality to assess global left ventricular (LV) longitudinal strain using angle-independent speckle tracking. We hypothesized that AFI global LV strain immediately after acute myocardial infarction (AMI) is related to long-term recovery of LV function after AMI. Consecutive patients were admitted for AMI and underwent primary percutaneous coronary intervention. Within 48 hours of admission (baseline), all patients underwent 2D echocardiography to assess LV volumes, LV ejection fraction (LVEF), severity of mitral regurgitation, wall motion score index (WMSI), and AFI global LV strain. At 12 months follow-up, LV volumes and LVEF were reassessed. The relation between baseline AFI global LV strain and recovery of LV function during follow-up was analyzed. A total of 147 patients (mean age 61 ± 11 years) were included. Significant relations were observed between baseline AFI global LV strain and peak level of troponin T (r = 0.64), peak level of creatine phosphokinase (r = 0.62) and WMSI (r = 0.52). Absolute improvement in LVEF ≥5% during follow-up was observed in 70 patients (48%). The remaining 77 (52%) patients did not show improvement in LVEF ≥5%. Patients with improvement in LVEF ≥5% during follow-up had a lower prevalence of the LAD as infarct-related artery (p<0.005), lower peak levels of troponin T (p<0.0001) and creatine phosphokinase (p<0.0001), lower WMSI (p<0.0001) and higher baseline AFI global LV strain (p<0.0001). Multivariate linear and logistic regression analyses demonstrated that baseline AFI global LV strain is an independent predictor for change in LVEF during follow-up after AMI. ROC curve analysis demonstrated that a cut off value for baseline AFI global LV strain of −14.2% yields a sensitivity and specificity of 76% (AUC 0.87, 95% CI 0.82–0.93, p<0.0001) to predict recovery of LV function during 12 months follow-up after AMI. Global left ventricular longitudinal strain assessed with AFI immediately after acute myocardial infarction is a reflector of infarct size and predicts long-term recovery of left ventricular function.