Accessing And Predicting The Change Of Left Ventricular Function In Patients With Acute Myocardial Infarction And Reduced Ejection Fraction By Left Ventricular Pressure–strain Loop

Objective The left ventricular pressure strain loop（LV–PSL）was used to evaluate changes in myocardial manual work in patients with acute ST-elevation myocardial infarction（STEMI）and reduced left ventricular ejection fraction（LVEF）,and to investigate the efficacy and applicability of early myocardial manual work parameters in predicting changes in LV systolic function,with the aim of providing a new reference for clinical treatment decision-making,prognosis judgment.Methods From March 2020 to December 2020,62 patients with acute STEMI who were treated with percutaneous coronary intervention（PCI）and exhibited an LVEF<50% in the first measurement in our hospital were selected.The general clinical data of all patients during hospitalization were recorded,including: demographic data,coronary heart disease risk factors,disease severity indicators,laboratory indicators,angiographic indicators and in-hospital adverse cardiac events.At the same time,60 healthy volunteers were enrolled as the control group.Transthoracic echocardiography was performed at the initial stages after PCI treatment（within 12h）and subsequently at 7d,and routine echocardiographic parameters were collected.An LV–PSL was used to evaluate left ventricular myocardial work parameters,including the global work index（GWI）,global constructive work（GCW）,global work waste（GWW）,and global work efficiency（GWE）.The experimental group was divided into two groups,including 32 patients in the recovery group（delta LVEF>5%）a recovery group and and 30 patients in the poor recovery group（delta LVEF<5%）,depending on whether the increase in the LVEF exceeded 5% 7d after the operation.Results1.Compared with the control group,the values of LVEF,GLS,GWI,GCW and GWE in the experimental group decreased significantly in the initial stages（within 12h）and 7d after PCI,and the values of GWW increased significantly（P < 0.05）.Compared with the measurements in the initial stage（within 12h）after PCI,the values of LVEF,GLS,GWI,GCW and GWE increased significantly（P<0.05）,and the values of GWW decreased,but the differences were not statistically significant（P>0.05）,over the 7-d period after treatment.2.Compared with those for the recovery group,the initial myocardial work indicators for the poor recovery group were impaired more significantly（P<0.05）.Compared with the measurements in the initial stages after the PCI treatment,the values of the myocardial work indicators for the recovery group improved significantly（P<0.05）,and for the poor recovery group improved lightly,over the 7-d period after treatment.3.The initial LVEF,GLS,GWI,GCW,GWW,and GWE were included in the basic model for multiple logistic regression.The results indicated that the initial myocardial work indicators: GWI,GCW,GWW,GWE increased the basic model incremental prognostic value（delta χ2=6.28,5.18,9.13,35.18 all P<0.05）;LVEF,GLS did not increased the basic model incremental prognostic value（delta χ2=0.12,1.28,all P>0.05）.4.According to analyses of the receiver operating characteristic（ROC）curve analysis,the initial GWE < 75.5% measured after the PCI treatment exhibited the highest sensitivity and specificity in predicting the poor recovery of the short-term left ventricular function after an acute STEMI,which were 96.7% and 90.6%,respectively（AUC=0.95,P=0.000）.5.The repeatability test results showed that the intra-observer and inter-observer repeatability of GWI,GCW,GWW and GWE were good.Conclusion1.The systolic functions of the left ventricle was severely impaired in patients with acute STEMI.2.7d after the PCI treatment,some acute STEMI patients showed significant improvement in left ventricular systolic function,while others showed persistent LV systolic dysfunction.3.It was found that the initial GWE is a more sensitive indicator for predicting the short-term changes in left ventricular function after PCI in patients with acute STEMI.4.LV–PSL can be used to accurately evaluate and predict the changes in myocardial work in patients with acute STEMI,which provides a new reference for clinical evaluation of myocardial function.