Objective To observe the value of tissue motion mitral annular displacement(TMAD)technique to assess left ventricular function in patients with cardiac amyloidosis.Methods A total of 34 adult patients with cardiac amyloidosis diagnosed by pathology were retrospectively included as the observation group,and 32 healthy adults were collected as the control group for the same period.Basic data of the subjects were collected,and data of routine ultrasonic parameters of left ventricular function and TMAD parameters were obtained,and then compared between groups.The correlation of TMAD parameters with left ventricular ejection fraction(LVEF)or mitral annular plane systolic excursion(MAPSE)were assessed.Results Compared with the control group,the observation group had higher levels of body surface area(BSA),systolic blood pressure,N-terminal pro-B-type natriuretic peptide(NT-proBNP),creatinine and urea(all P＜0.05).The observation group had increased values of ascending aorta(AO),left atrium(LA),interventricular septum(IVS),left ventricular posterior wall thickness in diastole(LVPWD),pulmonary artery(PA),and early diastolic peark velocity of mitral inflow(peak E),while smaller values of left ventricular end-diastolic dimension(LVEDD),LVEF,fractional shortening(FS),early diastolic tissue Doppler velocity E'septal(IVS E')and lateral(LW E')and MAPSE(all P＜0.05),and the LVEF in observation group was(58.18±7.09)％.For TMAD patameters,the observation group had smaller values of the following parameters on apical four chamber(A4C)view as medial displacement of mitral valve annulus(A4C MV1),displacement of lateral mitral valve annulus(A4C MV2),displacement of the midpoint of the mitral valve annulus(A4C Midpt)and the corresponding percentage(A4C Midpt％),as well as smaller values of the following paramets on apical two chamber(A2C)view as A2C MV1,A2C MV2,A2C Midpt and A2C Midpt％(all P＜0.05).In the observation group,A4C Midpt％showed a moderate positive correlation with LVEF(r=0.488,P＜0.05),and A2C Midpt showed a high positive correlation with M APSE(r=0.712,P＜0.05),and A4C MV2,A4C Midpt,A4C Midpt％,A2C MV1,A2C MV2,A2C Midpt％all showed a moderate positive correlation with MAPSE(r=0.420 to 0.691,all P＜0.05).Conclusion Compared with LVEF,the TMAD parameters might reflect the changes in left ventricular systolic function more sensitively in patients with cardiac amyloidosis.