Assessment Of Left Ventricular Diastolic Function Using Ultrasonic Vector Flow Mapping Combined With Two-dimensional Speckle Tracking Imaging In Graves Disease Patients

Objective:To evaluate the left ventricular diastolic energy loss and mechanical deformation using ultrasonic vector flow mapping combined with two-dimensional speckle tracking imaging in Graves'disease patients,and to reveal the spatio-temporal relationship between the left ventricular myocardial mechanical deformation and blood flow energy loss.Method:According to the guidelines of American Thyroid Association Guidelines for Diagnosis and Management of Hyperthyroidism and other causes of Thyrotoxicosis in 2016,104 cases of GD patients divided into two groups?GD1,n=45,HR<90 times per minute.GD2,n=59,HR?90 times per minute?were enrolled as two patient groups and forty-four healthy volunteers were employed as the control group.Left atrial diameter?LAD?,left ventricular end diastolic diameter?LVEDD?,interventricular septum thickness?IVS?,mitral early diastolic peak velocity?E?,the maximal blood flow velocity of mitral valve?A?,atrial systolic mitral annular early diastolic velocity?e?,two tricuspid annular velocity in early diastole?a?,aortic blood flow velocity?AV?were measured and calculated the E/A and E/e;Left ventricular ejection fraction?LVEF?was obtained with Simpson method in equipment.Early diastolic and late diastolic strain rate(s^-1)were analyzed with 2D-STI in apical four chamber?A4C?,three chamber?A3C?and two chamber?A2C?view;The whole left ventricular energy loss were measured with VFM imaging mode in isovolumic relaxation phase and rapid filling phase,slow filling period and atrial contraction in A4C,A3C,A2C,and the average energy loss of the three chambers of the heart were compared;Correlation analysis were performed among E,A,e,a,E/A,E/e,the left ventricular mechanical deformation and early diastolic and late diastolic overall energy loss.Result:1?General information and blood biochemical marks:there were no significant differences in age,body mass index of the three groups?P>0.05?.Heart rate?HR?of GD1 group and GD2 was higher than the control group,but only between GD2 group and control group had significant difference?P<0.05?.The systolic blood pressure?SBP?,pulse pressure?DP?,thyroid stimulating hormone?TSH?,free three triiodothyronine?FT3?,free thyroxine?FT4??Thyroid stimulation hormone receptor antibodies?TRAb?of GD1 group and GD2 group were significantly higher than the control group?P<0.05?,SBP,FT3,FT4 in GD2 group was significantly higher than those of GD1 group?P<0.05?.2?2D echocardiography and Doppler ultrasound measurement:AAO,LAD,LVEDD,IVS,e,E/e were not statistical difference in three groups?P>0.05?;EF of GD2 group was higher than those of GD1 group and the control group?P<0.05?;E,A,a,AV of two case groups were higher than those of control group,and compared with the control group,E/A of GD2 group decreased?P<0.05?.3?2D-STI for left ventricular mechanical deformation:early diastolic:the left ventricular longitudinal strain rate of two case groups were lower than the control group?P<0.05?,and GD2 group was lower than GD1group?P<0.05?.Atrial contraction:the left ventricular longitudinal strain rate of two case groups were lower than the control group?P<0.05?,and GD2group was lower than GD1 group?P<0.05?.4?VFM energy loss:The total energy loss of two case groups were significantly higher than that of control group?P<0.01?,and the overall energy loss in the GD2 group was higher than that of GD1 group?P<0.05?.5?Correlations:correlationship was revealed among E?A?E/A?e?a?E/e and the left ventricular's total energy loss during the rapid filling period?r=0.657?0.333?0.298?0.197?0.423?P<0.05??,and the left ventricular's total energy loss during the period of atrial contraction?r=0.276?0.664?-0.462?0.276?0.350?P<0.01??;There were different degrees of correlation between the left ventricular wall mechanical parameters and the left ventricular corresponding time energy loss:?A4C:r=0.363?0.314?P<0.01?;A3C:r=0.338?0.370?P<0.01?;A2C:r=0.361?0.359?P<0.01??.6?Multiple linear regression:the left ventricular's total energy loss during the rapid filling period independently associted with E??=0.751,P=0.001?and E/A??=-0.235,P=0.010?.The left ventricular's total energy loss during the period of atrial contraction independently associted with A??=0.715,P=0.001?and E/A??=0.300,P=0.018?.Conclusion:1?The left ventricular mechanical deformation of GD patients had decreased in various degrees in case of no significant difference of E/A and E/e between GD patient groups and the control group.2?When there were no significant difference in E/A and E/e among three groups,the overall EL of the patient groups in the left ventricular diastolic phase was higher than that of control group,and the overall EL of GD2 group was higher than that of GD1 group.3?The left ventricular blood flow parameters and myocardial mechanical parameters were correlated with the energy loss suggesting that the left ventricular global EL could be used to evaluate the left ventricular diastolic function.4?Combined with mechanics and hemodynamics,ventricular diastolic function of GD might be evaluated in a more comprehensive way.