Quantification Of Diastolic Dysfunction And Influencing Factors By GMPI In Patients With Known Or Suspected CAD

Objective:Left ventricular(LV)diastolic dysfunction(LVDD)is usually one of the earliest indicators in coronary artery disease(CAD),identifying the patients with a less favorable prognosis.Gated myocardial perfusion imaging(GMPI)is a noninvasive method to provide information for left ventricular diastolic function,including peak filling rate(PFR),mean first third filling rate(MFR/3)and time to peak filling(TTPF).Currently,PFR is a commonly used parameter in clinical studies,and diagnostic thresholds are established in different populations.Therefore,the purpose of this retrospective study was to investigate the influencing factors of LV diastolic dysfunction and to evaluate the clinical application value of MFR/3 and TTPF for impaired LV diastolic function.Methods:1.We analyzed 307 consecutive patients admitted to department of nuclear medicine from January 2014 to December 2019.Every patient in the present study was diagnosed as suspected or known coronary artery disease.All patients underwent a standard Stress gated MPI study.Peak filling rate(PFR),mean first third filling rate(MFR/3),time to peak filling rate(TTPF),End-diastolic volume(EDV),end-systolic volume,and left ventricular ejection fraction(LVEF)et.were also obtained by Quantitative gated SPECT(QGS)software.2.PFR<2.1 EDV/s was selected as the definition of an abnormal result in the present study.The study population was categorized into two groups,PFR<2.1 EDV/s is considered as left ventricular diastolic dysfunction group and PFR≥2.1 EDV/s is considered as normal diastolic function group.General clinical data were collected for all patients,including gender,age,body mass index(BMI),smoking,history of hypertension,diabetes,dyslipidemia and hyperhomocysteinemia.Resting systolic BP and diastolic BP before the trolley test,whether the patient’s heart rate is in a secondary quantity during the trolley test were recorded.The data were analyzed using SPSS software to determine the factors affecting diastolic function,analyze the correlation of diastolic function parameters and other variables,and find the optimal threshold for MFR/3 and TTPF to predict impaired LV diastolic function by ROC curve.Results:1.A total of 307 patients were included in this study,with a high incidence of hypertension(54%)and dyslipidemia(43%).There were 95 patients in the LVDD group and 212 patients in the non-LVDD group,and the binary logistic regression analysis results showed that:Heart rate(OR=0.019,95%CI:0.001-0.314,P=0.006),female(OR=3.691,95%CI:1.084-12.564,P=0.037),age(OR=2.575,95%CI:1.426-4.652,P=0.002),smoking(OR=3.426,95%CI:1.121-10.474,P=0.031),hypertension(OR=2.715,95%CI:1.051-7.012,P=0.039),CAD(OR=3.614,95%CI:1.143-11.420,P=0.029),EDV(OR=1.069,95%CI:1.026-1.114,P=0.001),ESV(OR=1.103,95%CI:1.036-1.174,P=0.002),LVEF(OR=10.699,95%CI:2.158-53.04,P=0.004)were all contributing factors to left ventricular diastolic dysfunction.2.PFR showed a highly correlation with ESV,PER,LVEF,MFR/3,and heart rate(r_s:-0.725,-0.972,0.733,0.850,0.730,All P<0.01);a moderate correlation with SMS,EDV,and TTPF(r_s:-0.503,-0.637,-0.578,All P<0.01);And a weak or very weak correlation with STS,SIES,SBP,and EI(r_s:-0.462,-0.315,0.136,-0.166,All P<0.01).There was no correlation between PFR and age and DBP(r_s:0.094,0.074,both P>0.05).Multiple linear regression equations showed that PFR was mainly affected by PER,sex,heart rate,LVEF,and EI,with PER being the most affected.MFR/3 showed a highly associated with PER and heart rate(r_s:-0.868,0.748,All P<0.01),a moderate correlation with EDV,ESV,LVEF,and TTPF(r_s:-0.552,-0.613,0.599,-0.648,All P<0.01),and a weak or very weak correlation with SMS,STS,SIES,resting SBP,resting DBP,and SIED(r_s:-0.389,-0.344,-0.339,0.165,0.129,-0.156,All P<0.01).However,there was no correlation between MFR/3 and age and EI(r_s:-0.035 and-0.048,All P>0.05).Multiple linear regression equations showed that MFR/3 was mainly affected by heart rate,LVEF,EI,and dyslipidemia,in which heart rate and LVEF were affected to a greater extent.Strong correlation between TTPF and heart rate(r_s:-0.914,P<0.01);The TTPF and PER showed a moderate correlation(r_s:0.581,P<0.01);TTPF showed a very weak correlation with age,SBP,DBP,STS,EDV,and SIED(r_s:0.186,-0.158,-0.205,-0.127,0.132,0.157,All P<0.01).No correlation with SMS,ESV,LVEF,SIES,EI(r_s:-0.110,0.104,-0.013,0.067,-0.050,All P>0.05).Multiple linear regression equations showed that TTPF was mainly affected by heart rate,LVEF,and diabetes history,with heart rate affecting the most.3.The ROC curves of MFR/3 and TTPF were made with PFR<2.1 EDV/s,and the area under the curve[(AUC),95%CI]was 0.928(0.899,0.956)and 0.755(0.695,0.814),respectively.The optimal threshold for MFR/3 is 0.775 EDV/s,with a sensitivity of 87.4%and 83%specificity for predicting LV diastolic dysfunction.The optimal threshold for TTPF was 240.5 ms,with a sensitivity of 69.5%and 72.6%specificity for predicting LV diastolic dysfunction.MFR/3 had superior diagnostic efficacy than TTPF in predicting left ventricular diastolic dysfunction.Conclusions:Heart rate,sex,age,smoking,history of hypertension,CAD,and impaired LV systolic function were the contributing factors for left ventricular diastolic dysfunction.PFR is mainly affected by PER,sex,heart rate,LVEF,and EI,while MFR/3 is mainly affected by heart rate,LVEF,EI,and dyslipidemia.TTPF is mainly affected by heart rate.It can be concluded that TTPF is a more objective and stable indicator under normal heart rate.MFR/3 and TTPF have some clinical utility in predicting left ventricular dysfunction,and MFR/3 has better diagnostic efficacy than TTPF.