ObjectiveTo evaluate the left atrial systolic function in patients with paroxysmal atrial fibrillation（PAF）by tracking of mitral annular displacement technology（TMAD）.MethodsThirty patients with PAF（case group）and 30 normal controls（control group）were selected.The mean value of the peak strain rate of left ventricular systolic

early and late diastolic of left atrium（mSRs

mSRe

mSRa）

standardized left atrial maximal volume index（LAVimax）

minimal volume index（LAVimin）and pre systolic volume index（LAVip）were obtained by two-dimensional speckle tracking echocardiography（2 D-STE）

and left atrial total emptying fraction（LATEF）

passive emptying fraction（LAPEF） and active emptying fraction（LAAEF） were calculated. Meanwhile

the time-displacement curve was obtained by TMAD

the left ventricular systolic mitral annular displacement（TMAD-D）and left atrial systolic mitral annular displacement（TMAD-S）were measured.And the differences of above parameters were compared between the two groups.Receiver operating characteristic（ROC）curve was drawn to analyze the values of strain rate and TMAD parameters in detecting PAF.And the repeatability test of TMAD parameters was conducted.The measurement time of TMAD and 2 D-STE was recorded.Results LAVip in case group were higher

and LATEF

LAPEF

LAAEF

mSRs

mSRe

mSRa

TMAD-D

TMAD-S in case group were lower

the differences were statistically significant（all P<0.05）.The area under the ROC curve of TMAD-D

TMAD-S

mSRs and mSRa in predicting PAF were about 0.867

0.808

0.944 and 0.850

respectively.The intra-observer correlation coefficients of TMAD-D and TMAD-S mean were 0.964 and 0.888

and the inter-observer correlation coefficients were 0.918 and 0.860

respectively.The measurement time of TMAD was significantly shorter than that of 2 D-STE（P<0.05）.ConclusionTMAD can detect the changes of left atrial systolic function in patients with PAF

and the detection time of TMAD is shorter than that of2 D-STE.