Application Study On Quantification Of Myocardial Blood Flow With PET/CT In Diagnosis And Evaluation Of Coronary Microvascular Diseases

Objective:To diagnose coronary microvascular disease(CMVD)and analyze clinical risk factors with Positron emission tomography/computed tomography(PET/CT)myocardial perfusion imaging(MPI).The study was divided into two parts:(1)to explore the value of quantitative and semi-quantitative parameters for the CMVD diagnosis and analyze the clinical risk factors of CMVD;(2)to explore the clinical risk factors,cardiac function parameters and the quantitative parameters of PET/CT in female patients with CMVD.Methods:Part I.(1)Suspected CMVD patients in Teda international cardiovascular hospital from September 2017 to September 2018 were retrospectively analyzed.The clinical risk factors and image parameters,such as rest and stress myocardial blood flow(MBF),coronary flow reserve(CFR)in different coronary territory,left ventricular coronary flow reserve(LV-CFR),summed stress score(SSS),summed rest score(SRS),summed difference score(SDS),transient ischemia dilation(TID),were collected,analyzed and compared between the CMVD and non-CMVD group who were divided by the LV-CFR value of 2.5,respectively.Part II.(2)Suspected female patients with CMVD in Teda international cardiovascular hospital from September2017 to August 2019 were retrospectively analyzed.The clinical risk factors,such as hypertension et al,rest and stress MBF,CFR,LV-CFR and left ventricular systolic function(LVEF)were collected,analyzed and compared between the CMVD and non-CMVD group who were divided by the LV-CFR value of 2.5,respectively.IBM SPSS 22.0 software package was used for statistical analysis,Two samples t-test was used when continuous variables were normal distribution and homogeneous variance,mann-whitney U test was used when it was not.Chi-square test and/or Fisher’s exact probability method were used for the categorical variables.Pearson test was used for the correlation analysis.Bilateral P values<0.05 was considered to be statistically significant.Results:Part I.(1)54 subjects were included in this study.It was found that the percentage of women patients with CMVD was more than that of men,and the difference was statistically significant(X~2=4.800,P=0.027).The percentage of hypertensive patients with CMVD were more than that of non-hypertensive patients(X~2=4.395,P=0.036).Other clinical risk factors showed no statistically significant(all P<0.05).There was no statistically significant in semi-quantitative parameters for SSS,SRS,SDS and TID between the two groups(all P values were>0.05).In patients with CMVD,1 case of single-vessel coronary artery CFR decreased,6 cases of double-vessel coronary artery CFR decreased,and 27 cases of three-vessel coronary artery CFR decreased.The rest LV-MBF of the CMVD group was relativley higher and the stress LV-MBF was lower than those of the non-CMVD group(0.74±0.16m L/g/minvs0.63±0.09m L/g/min,1.52±0.36m L/g/minvs1.89±0.22m L/min/g,t values were 2.92 and-4.50,P values<0.05).(2)Part II.There were 75 patients enrolled in this study.BMI of CMVD group was higher than that of non-CMVD group(26.93±3.52kg/m~2 vs 23.83±3.42kg/m~2,t=3.63,P<0.05).BMI was negatively correlated with LV-CFR(r=-0.341,P=0.003).LV-CFR of the overweight group was lower than that of non-overweight group who were divided by the values of BMI24kg/m~2(2.18±0.47kg/m~2 vs 2.54±0.55kg/m~2,t-value-2.89,P value:0.005).There was no difference in other clinical risk factors between the two groups(X~2value:0～3.002,u value:586.5,P all>0.05).The rest LV-MBF in the CMVD group was higher and stress LV-MBF was lower than that of the non-CMVD group(u value:417.5,t value:-4.54,all P<0.05).The rest and stress LVEF were no statistical difference between the groups(t valve:1.40 and 0.69,all P>0.05).Conclusions:In the CMVD group,the percentage of women was more.In the female patients with non-obstructive coronary stenosis,the proportion of CMVD was higher,and BMI was correlated with female CMVD,which was negatively correlated with LV-CFR.Hypertension is common in CMVD group.The CFR of three coronary artery territory diffusely being decreased was the common features for quantative PET/CT MPI.Quantification of PET/CT MPI imaging is significantly better than routine MPI for patients with suspected CMVD.