Study Of Cardiac Magnetic Resonance IVIM Imaging For Evaluation Microvascular Dysfunction In Hypertrophic Cradiomyopathy

Objective To evaluate microcirculatory dysfunction in hypertrophic cardiomyopathy?HCM?by using intracardiac incoherent motion?IVIM?.Materials and Methods Twenty-four hypertrophic cardiomyopathy patients?HCM group?who completed 3.0 T cardiac magnetic resonance?CMR?examinations in the Department of Radiology,First Affiliated Hospital of Lanzhou University from April 2016 to October 2017 were collected.At the same time,12 Healthy volunteers were selected served as normal controls.All 24patients with HCM underwent CMR including film scans,IVIM scans,cardiac first-pass perfusion,and delayed-enhanced scans.Measured 16 segments of myocardial perfusion fraction f(fraction of ADC_fast),pure diffusion coefficient D(ADC_slow),perfusion coefficient D*(ADC_fast),and end-diastolic myocardial thickness?EDTH?.The normal control group was set as group A.The HCM group was set to the non-hypertrophic group?B group?and the hypertrophic group?b group?according to whether the HCM group was hypertrophied or not,and the hypertrophy segment group?group b?was set to light?b1?,middle?b2?,severe?b3?,and extremely severe?b4?groups according to the degree of hypertrophy.At the same time,according to whether there is delayed enhancement in the 16 segments,the HCM group was set as the non-enhanced segment group?C group?and the enhanced segment group?c group?.and the SPSS 22.0 statistical software was used to test the parameters between the normal group and the HCM group,Each parameter in the HCM group with independent sample t test,LSD-t test,Kruskal-Wallis test and Mann-Whitney test.Spearman correlation analysis was used to analyze the correlation between IVIM parameters and myocardial EDTH in 16 segments.Results The thickest parts of the myocardium in the normal control group and the HCM group were mainly found in the basal and interventricular septum?paragraphs 2,3,8,9?.The end-diastolic ventricular wall thickness?EDTH?in the 16 segments of the HCM group was higher than that of the corresponding 16-segment end-diastolic ventricular wall thickness?EDTH?in the control group,and the difference was significant?p<0.01?.Delayed intensification in the HCM group also occurred mainly in the basal and mid-segment septum?paragraphs 2,3,8,9?.The D*and EDTH values were significantly different between the normal control group and the HCM group?p<0.01?.The D*in the HCM group was significantly smaller than that in the normal control group,and the EDTH was significantly larger than that in the normal control group;the f and D values were not statistically significant?p>0.05?.The IVIM parameters f,D,and D*in the non-hypertrophic segment group?B group?and hypertrophic segment group?b group?were lower than those in the normal control group?group A??p<0.05?,f and D*values decreased more significantly?p<0.01?.The decrease in f and D*values was more pronounced in group b than in group B?p values were 0.000,0.001,respectively?.The EDTH in groups A,B,and b gradually increased with significant differences?p<0.01?.The D*values were statistically significant between the light,moderate,severe,and extremely severe?b1,b2,b3,and b4?groups of HCM?p<0.05?,but there was no statistical difference among the hypertrophic groups at each level?p>0.05?;The overall trend of f and D values in the four groups was not statistically significant?p>0.05?;EDTH was significantly different?p<0.01?.The f,D,and D*in the HCM non-enhanced segment group?C group?and the enhanced segment group?C group?were lower than those in the normal control group?A group??p<0.05?,and the D*decreased more significantly?p<0.01?.The f and D*values in group C were lower than those in group C?p values were 0.007 and 0.032,respectively?,with a significantly lower f value?p<0.01?,while there was no statistically significant difference between d values?p=0.130?.).The EDTH groups in groups A,C,and C gradually increased with significant differences?p<0.01?.The EDTH value was negatively correlated with the f and D*values?r values were-0.209,-0.310,respectively?.Conclusion The application of 3.0 T cardiac IVIM-MRI technique can non-invasively and quantitatively evaluate the microcirculatory dysfunction of hypertrophic cardiomyopathy,suggesting that the early microcirculation function of the regional myocardial segments without hypertrophic and non-enhanced segment Abnormal changes,and found that the severity of microcirculatory dysfunction and myocardial thickening were positively correlated.The D*value can more sensitively indicate the myocardial microcirculatory perfusion injury of HCM,it will be mainly used to monitor and predict the changes of myocardial microcirculation perfusion,thus providing Certain theoretical basis for clinical diagnosis,risk stratification,prognosis analysis and diagnosis and treatment plan for HCM.