Measurment Of Left Ventricular Global Longitudinal Strain In Patients With Atrial Fibrillation By Speckle Tracking Imaing

Objective:1. To compare the difference of left ventricular global longitudinal strain (GLS)in atrial fibrillation (AF) patients’ different RR intervals using the two-dimensional speckletracking imaging (2DSTI).2. To evaluate the variation of GLS between the AF patientswith or without heart failure (HF).Methods: Select a total of99cases of patients with atrial fibrillation,51AF patients withnormal LVEF（EF均>55%）,48AF patients with decreased LVEF（EF均<45%） and50healthy subjects underwent standard conventional. GE’s Vivid E9using color Dopplerultrasound imaging device, using real-time three-planar imaging technique to obtain sevenconsecutive cardiac cycles apical four-chamber view, apical two-chamber view, apical leftventricular long axis of the two-dimensional echocardiography. The ECHOPAC softwarewas used to analyze the left apex longitudinal strain. AF patients were grouped by differentRR intervals (the previous RR interval of every cardiac cycle). A group: RR intervals800-1000ms; B group: RR intervals650-800ms; C group: RR intervals <650ms. Wecompare the impacts on left ventricular longitudinal strain in different cardiac cycles. Ifthere is no difference in groups, we compare the average left ventricular longitudinal strainof AF groups with control group (healthy subjects). If there is difference in groups, weeliminate these data first and compare the average value of AF groups with control group.The statistical analysis of this study was performed with an SPSS17.0(SPSS Inc., Illinois,USA) software package. All measurement data was expressed by mean±SD. Continuousvariables were analyzed with a paired t-test, an independent-sample t-test and ANOVA(N-group analysis). P-value <0.05was considered statistically significant.Results:1. There was no statistically difference compared with age, gender, BSA between AF andcontrol group (P>0.05). But the heart rate (HR) in AF was faster than in control group (P <0.05). There was no statistically difference in AF group without HF of LVDd, LVDs, EF(P>0.05), but there were statistically difference in AF with HF (P <0.01).2. Left ventricular longitudinal strain of various views decreased with RR intervals isshortened in AF patients without HF, but the RR interval800-1000ms group no statisticallydifferences RR interval650-800ms group. RR interval <650ms group had statisticallydifferences with the other two groups (P <0.05).Left ventricular longitudinal strain valuesfor each section also becomes smaller with RR interval is shortened,but no statisticallydifference in the three groups of AF patients with HF(P>0.05).3. There was a statistically difference of left ventricular longitudinal strain between AFwithout HF (average removal <650ms RR interval) and control group. Left ventricularlongitudinal strain in AF with HF (average removal <650ms RR interval) wassignificantly decreased than in control group and in AF without HF (P <0.01).4. Repetition test: we repeated measuring all data of patients with atrial fibrillation1weeklater, but there was no difference between them (P>0.05).Conclusion:1. Left ventricular apical views obtained by real-time three-planar imaging technique canbe analyzed the left ventricular GLS and myocardial function with2DSTI. There weresmall effects and good repeatability on GLS of difference RR intervals (650ms-1000ms).2. Left ventricular longitudinal strain of various views in AF without HF was decreasedthan in control group,there was statistically difference.3.Left ventricular longitudinal strain in AF with HF was significant decreased, conformedto the characteristics of left ventricular myocardial mechanics change in HF patients.