The Rule of Speckle Tracking Echocardiography Indicators, Including Post Systolic Shortening Index, in Predicting Left Ventricular Ejection Fraction Improvement and Detection of Viable Myocardium in Patients With ST-segment Elevation Myocardial Infarction who Undergo Late Percutaneous Coronary Intervention

Background: ST-segment elevation myocardial infarction (STEMI) can lead to significant changes in left ventricular (LV) structure, ultimately resulting in left ventricular remodeling (LVr). Objectives: The present study aims to investigate the capability of speckle tracking echocardiography (STE) and Post Systolic Shortening Index (PSSI) to predict LVr, improvement in left ventricular ejection fraction (LVEF), and the detection of viable myocardium in STEMI patients. Methods: This prospective cohort study included 47 patients with STEMI and Q-ST elevation in V1 - V4 precordial leads on electrocardiogram (ECG), who underwent percutaneous coronary intervention (PCI) after 24 hours (late PCI). Echocardiography was performed before PCI and 6 weeks post-PCI. Results: Left ventricular remodeling and improvement in LVEF were observed in 15 (31.9%) and 23 (48.9%) patients, respectively, after PCI. The average pre-PCI PSSI in patients with LVr was significantly lower (P = 0.005) than in those without remodeling. Conversely, the average pre-PCI PSSI in patients with improved LVEF was significantly higher (P = 0.004) than in those without improvement. The receiver operating characteristic (ROC) curves indicated that pre-PCI PSSI can predict LVr (AUC = 0.74; 95% CI: 0.6 - 0.91; P = 0.005) and LVEF improvement (AUC = 0.75; 95% CI: 0.6 - 0.89; P = 0.004) post-PCI. Cut points of 19 and 20 for pre-PCI PSSI had the highest accuracy for predicting LVr and LVEF improvement post-PCI (74.47% and 72.34%, respectively). Conclusions: The study demonstrates that in STEMI patients undergoing late PCI, STE indicators, including PSSI, are predictive of LVr, LVEF improvement, and can identify viable myocardium.