Preliminary Study Of Left Ventricular Pressure Strain Loop On Myocardial Work In Patients With Myocardial Infarction After PCI

Objective:（1）To evaluate the myocardial work of patients with myocardial infarction by left ventricular pressure strain loop,and to explore the clinical value of myocardial work parameters in the diagnosis of myocardial infarction.（2）Left ventricular pressure strain loop was used to detect the occurrence of heart failure after myocardial infarction in the early stage.Methods:From December 2020 to February 2022,A total of 70 patients with myocardial infarction diagnosed clinically were collected as the case group and divided into normal systolic function group（n=40）and reduced systolic function group（n=30）and 50 normal healthy subjects were enrolled in the First Hospital of Jilin University,the latter were enrolled as the control group.Dynamic images of the apical four-chamber,two-chamber and three-chamber sections were collected respectively,then the Global longitudinal strain and Peak strain dispersion of the left ventricle can be obtained by Echo PAC work station.Enter the myocardial work analysis mode to obtain LV-PSL,we can get the Global work index、Global constructive work、Global wasted work、Global work efficiency、Global positive work、Global negative myocardial work、Global systolic constructive work、Global systolic wasted work finally.（1）Analyze the general clinical data and laboratory data of case group and normal control group;（2）The results of echocardiography and myocardial work in case group and normal control group were statistically analyzed;（3）The ROC curve was used to find the best boundary value（when the yoden index was the largest）,and the differences of various indexes were compared by the one-way variance method.All results used the two tailed method,with P < 0.05 as the difference,which was statistically significant.Results:（1）Compared with the control group,the BMI,body fat rate and waist circumference of the case group were significantly higher,and the skeletal muscle rate and muscle rate were significantly lower,the difference was statistically significant;（2）Compared with the control group,the left atrial diameter,left ventricular end diastolic diameter,EDV and ESV in the case group increased significantly,while the ventricular septum e ’and lateral wall e’ decreased significantly,the difference was statistically significant（P < 0.05）.Compared with the normal group,the diameter of aorta and right ventricle in the myocardial infarction group with normal systolic function increased,and the difference was also statistically significant（P < 0.05）;The diameter of aorta and right ventricle in myocardial infarction group with reduced systolic function increased,but there was no significant difference（P > 0.05）.But the difference was not statistically significant（P > 0.05）.Compared with the myocardial infarction group with normal systolic function,the left ventricular end diastolic diameter,EDV and ESV in the myocardial infarction group with reduced systolic function increased significantly,the difference was statistically significant（P < 0.05）,and there was no significant difference in other indexes between the two groups（P > 0.05）.（3）Compared with the control group,GWE,GWI,GPW,gscw and GLS in the myocardial infarction group with normal systolic function decreased significantly,and gww,gnw,gsww and PSD increased significantly,the difference was statistically significant（P < 0.05）,while GCW decreased,but the difference was not statistically significant（P > 0.05）.Compared with the control group,GWE,GWI,GCW,GPW,gscw and GLS in the myocardial infarction group with reduced systolic function decreased significantly,and gww,gnw,gsww and PSD increased significantly（P < 0.05）.Compared with myocardial infarction patients with normal systolic function,GWE,GWI,GCW,GPW,gscw and GLS in myocardial infarction group with reduced systolic function were significantly lower（P < 0.05）,gww,gnw,gsww and PSD increased（P >0.05）.（4）The sensitivity and specificity of GLS and myocardial work index were compared.Among them,the sensitivity and specificity of GWE were 82% and68%;The sensitivity and specificity of GLS were 78% and 92%.Conclusion:LV-PSL can analyze the changes of myocardial work,which is related to LVEF and can reflect the left ventricular systolic function.Even if the left ventricular systolic function is normal,the related parameters of cardiac work index in patients with myocardial infarction are still lower than those in normal subjects,indicating that the myocardial contractile function has not fully recovered after myocardial infarction and needs regular follow-up observation.The analysis of myocardial work in patients with myocardial infarction can early monitor the occurrence of heart failure and provide a new reference index for clinical diagnosis,treatment and prognosis evaluation of myocardial infarction.