Early Evaluation Of Left Ventricular Systolic Function In Nonobstructive Hypertrophic Cardiomyopathy By The Three-dimensional Speckle Tracking Imaging(3D-STI)

Objective 1.To investigate the impact of the combined deformation parameters(CDP)in the quantitative evaluation of left ventricular(LV)systolic function in early diagnosis of hypertrophic cardiomyopathy(HCM)with three-dimensional speckle tracking imaging(3D-STI)technique.2.To compare the accuracy and sensitivity of different routine 3D-STI parameters in the early diagnosis of HCM.Methods 1.Subjects: 33 patients with nonobstructive HCM diagnosed by clinical assessments and routine echocardiography were recruited in the experimental group,i.e.the HCM group;23 healthy volunteers with comparable demographic data were recruited in the control group.2.Equipment: GE Vivid E9 and E95 Dimension Ultrasound System(M5Sc ultrasonic probe of 1.7~3.3MHz,4V ultrasonic probe of 1.7~3.3MHz);Echo PAC Work Station(Echo PAC 201).3.Measurements:Firstly,we collected all 3D images of the HCM and healthy subjects by GE Vivid E9 and E95 Dimension Ultrasound System and imported the data to the Echo PAC work station.Then we selected ‘4D Auto LVQ' mode to conduct conventional ultrasound measurement(i.e.,LVEF,LVEDV,LVESV,EDMass,SPI),as well as the rotation and torsion values(GAS,GLS,GCS,GRS,Ptw,Ptor).Subsequently,we calculated the combined deformation parameters(CDPs),i.e.(1)deformation product(DP): Ptw×GLS(o×%),and(2)deformation index(Def I): Ptw/GLS(o/%).Finally,we analyzed all the parameters and compared the differences between the two groups(i.e.,the HCM and the healthy groups).Receiver Operating Characteristic Curve(ROC Curve)was used to evaluate the application value of left ventricular 3D strain parameters,twist and CDP in the diagnosis of HCM.Correlation analysis were conducted between each echocardiographic parameter(i.e.,GLS,GAS,GRS,GCS,Ptw,Ptor,DP,and Def I)and LVEF.Results 1.There is no significant difference in the demographic data(i.e.,gender,age,body surface area and heart rate)between both groups.The values of IVSD,LVPWD,E/e' and EDMass in the HCM group were higher than those in the control group.The intergroup differences were statistically significant(P<0.05);2.The values of LVGAS,LVGLS,LVGCS and LVGRS in the HCM group were significantly lower than those in the control group(P <0.05);3.The values of Prot-base,Prot-ap,Ptor-base,Ptor-ap,Ptw and Ptor in the HCM group were significantly higher than those in the control group(P <0.05).4.DP and Def I in the HCM group were significantly higher than those in the control group(P <0.05).5.Correlation analysis showed negative correlation between GCS-LVEF,DP-LVEF,and Def I-LVEF(r:-0.491,-0.504,-0.345,P<0.05)and positive correlation between GRSLVEF and Ptw-LVEF(r: 0.473,0.547,P<0.05).6.By the ROC curve,it was demonstrated that the AUC(area under roc curve)of DP and Def I were 0.79 and 0.99.The cut-off points for HCM prediction were-82.85 o×%(specificity 87.00% and sensitivity 66.70% for DP)and-0.35 o/%(specificity 97.50% and sensitivity 97.00% for Def I),respectively.Conclusions: Real-time 3D-STI technique can accurately and quantitatively evaluate the overall LV systolic function of HCM patients with multiple parameters and multiple directions.The CDP parameters based on 3D-STI are more comprehensive for the evaluation of systolic function and are more sensitive to early myocardial injury,providing essential information for early diagnosis and treatment instruction.