【】Objective To evaluate the application of cardiac four-dimensional quantitative technique in the evaluation of left ventricular systolic function after coronary stent implantation. Methods Use GE-vivid-E9 high-end color ultrasound, four - dimensional volume imaging technology. Set up 120 cases of normal heart 17 segmental left ventricular wall myocardial longitudinal strain and radial strain, circumferential strain and area of normal reference value of strain. Study of 29 cases of patients with myocardial infarction and section strain changes of myocardial infarction by coronary angiography to judge the position and size of infarction and the consistency of the four-dimensional ultrasound, and compared with normal heart 17 segmental left ventricular wall myocardial longitudinal strain and radial strain, circumferential strain and the area strain were analyzed. After percutaneous coronary intervention (PCI), the range of myocardial infarction and segmental strain and preoperative analysis were reviewed in March. Results In 29 cases of myocardial infarction, the site and scope of infarction were consistent with the results of coronary angiography, and the longitudinal strain, radial strain, circumferential strain and area strain of the infarcted segment were significantly lower than the normal control values. March of PCI postoperative myocardial infarction review of the scope change, the range decreased significantly in patients with acute myocardial infarction infarction, myocardial longitudinal strain and radial strain, circumferential strain and the area strain recover to the normal range, left ventricular ejection fraction(LVEF) > 50%; The range of subacute myocardial infarction was narrowed, the corresponding segmental strain improved, and the LVEF increased >5%. There was no significant reduction in the extent of the myocardial infarction, the corresponding segmental strain showed no significant improvement, and the LVEF increased <5%. Conclusion The four-dimensional quantitative technique of the heart can better identify the small differences in the spatial and temporal distribution of myocardial movements in each segment of the left ventricle, and the motion state of the left ventricular wall can be quantitatively analyzed in real time.