Layer-specific Analysis in Patients with ST Segment Elevation Myocardial Infarction

Objective To evaluate left ventricular wall function after ST segment elevation myocardial infarction(STEMI) by layer-specific analysis and determine if the layer-specific parameters can predict left ventricular remodeling(LVR). Methods Thirty nine patients with first STEMI who had successful primary percutaneous coronary intervention(P-PCI) were studied, while 30 healthy individuals were included as normal control. Echocardiographic examinations were performed in STEMI patients within 48 h after P-PCI (before follow-up) and 6 months later (follow-up). Three dimensional cardiac function and longitudinal, circumferential 3-layer strain were analyzed. Results In STEMI, longitudinal endocardial strain was higher than epicardial strain (P<0.01), circumferential strain decreased from endocardium to epicardium gradually (P<0.01). Longitudinal and circumferential 3-layer strain at follow-up was higher than that before follow-up (P<0.01), but lower than that in control group(P<0.05). LVR group had lower longitudinal and circumferential 3-layer strain （P<0.05). Longitudinal epicardial strain was the independent predictor of LVR(odds ratio:3.332,95% confidence interval：1.124-3.882,P=0.03), the cut off value of -9% yielded 89.5% sensitivity and 70.2% specificity. Conclusion Strain decreased from endocardium to epicardium within 48 h after P-PCI in STEMI. Myocardial function was lower in LVR group. Longitudinal epicardial strain could be employed as an independent predictor of LVR after STEMI.