Assessment of Left Ventricular Systolic Function After Revascularization in Patients with ST Segment Elevation Myocardial Infarction by Stratified Strain Technique

Objective: Stratified strain was used to evaluate the local stratified strain and the overall longitudinal strain of the left ventricle of the affected myocardium after revascularization in patients with ST-segment elevation myocardial infarction (STEMI).Methods: 120 patients diagnosed as STEMI in the Affiliated Hospital of Jiangsu University from July 2017 to August 2018 were selected. According to the time from symptom onset to balloon dilation (S-TO-B), 120 patients were divided into group A (S-TO-B≤6h) and group B (6h<S-TO-B <12h) .The changes of left ventricular global longitudinal strain (GLS), local partial layer strain (TLSendo, TLS-mid, TLSepi) and LVEF were compared between the two groups immediately after operation, 3 hours ,24 hours and 1 week after operation. The incidence of major adverse cardiovascular events (MACE) and LVEF were followed up during hospitalization and one month after operation.Results: In group A, TLSendo, TLSmid, TLSepi and GLS increased gradually at each time after vascular opening; in group B, TLSendo, TLSmid, TLSepi and GLS decreased immediately after vascular opening 3 hours after surgery, with obvious TLSendo and gradually increased, but the increase was smaller than that in group A. TLSendo,TLSmid, TLSepi and GLS increased in all patients one week after operation, but TLSendo and TLSepi increased more significantly than TLSmid, and GLS changed less. TlSendo increase of 4.50% is the most accurate parameter to predict the significant improvement of left ventricular systolic function in patients with STEMI one month after operation, with an AUC area of 0.87, sensitivity and specificity of 80.0% and 86.0%, respectively.Conclusions: Layered strain technique can be used to evaluate the myocardial strain in patients with STEMI, and recognize the effect of S-TO-B on the prognosis of STEMI, which has important clinical application value.