Correlation between myocardial infarction activity assessed by cardiac magnetic resonance imaging and the evolution of cardiac function after PCI

Objective:To investigate the correlation of cardiac magnetic resonance imaging(MRI)in the assessment of myocardial activity in patients with myocardial infarction and the outcome of cardiac function after PCI.Methods:30 patients with myocardial infarction(MI)who had complete clinical and imaging data from July 2016 to December 2018 after PCI were analyzed retrospectively.MR and echocardiogram were performed before and 6 months after PCI,and the parameters related to left ventricular function were measured by post-processing software of MRI workstation.The left ventricular transmural degree of CMR late gadolinium enhancement was compared with the left ventricular wall motion degree of 6-month echocardiography as a standard to judge the viable myocardium.Result:There were 193 left ventricular segmental abnormalities in 30 cases,including 121 viable myocardium and 72 non viable myocardium in CMR-LGE before operation.Six months after PCI,echocardiography showed that 125 of 193 abnormal segments of left ventricle detected by CMR-LGE before PCI were viable myocardium and 68 were non viable myocaridium.The sensitivity and specificity of CMR-LGE to determinate of viable myocardium were 92.0%and 91.1%respectively.The larger the non-viable myocardial area of the left ventricular wall,the worse the recovery of wall motion ability,and there was a negative correlation between them(r=0.416,P<0.05).The first-pass perfusion time in CMR-LEG region was significantly longer than that in normal myocardial region(4.85(+)1.51)s and(3.79(+)1.73)s,respectively.The difference was statistically significant(t=5.191,P<0.05).Conclusion:MRI can evaluate the myocardial activity of myocardial infarction,reflect the range of viable myocardium,and provide imaging basis for clinical treatment and prognosis.