Objective To evaluate the value of two-dimensional speckle tracking echocardiography (2D-STE) in assessing left ventricular systolic function,diastolic function and synchrony with different QRS complex duration in complete left bundle branch block (CLBBB) patients with preserved left ventricle ejection fraction (LVEF).Methods A total of 44 patients with CLBBB and LVEF≥50％ were included.All the patients were divided into two groups based on QRS duration,QRS＞150 ms as wide QRS group and 120 ms≤QRS≤150 ms as narrow QRS group.And 30 healthy people were included as control group.Two-dimensional echocardiography and 2D-STE were performed.Ieft ventricle longitudinal peak stain of global,septum and free wall (LS-G,LS-Sept,LS-Lat),standard deviation of time to peak systolic strain for the 18 left ventricular segments (SDt) and index of left yen tricular diastolic function (EDT,E/A and E/e') were measured.Results SDt values of wide QRS group and narrow QRS group were significantly higher than that of control group (both P＜0.01).And SDt of wide QRS group was significantly higher than that of narrow QRS group (P＜0.05).LVEF and LS-G in wide QRS group were significantly lower than those in both narrow QRS group and control group (all P＜ 0.05),while there was no significant difference between narrow QRS group and control group (all P＞0.05).The LS-Sept in wide QRS group and narrow QRS group were both lower than that of control group (both P ＜0.01).And LS-Sept in wide QRS group was lower than that of narrow QRS group (P＜0.01).LS-Lat in narrow QRS group was separately higher than those of both wide QRS group and control group (both P＜0.05),while there was no significant difference of LS-Lat between wide QRS group and control group (P＞0.05).Compared with control group,E/A and EDT decreased and of E/e' increased in both wide QRS group and narrow QRS group (all P＜0.05).While there was no significant difference between wide QRS group and narrow QRS group (all P＞0.05).Conclusion In patients of wide QRS CLBBB with preserved LVEF,left ventricular systolic,diastolic function and synchrony decrease,while left ventricular systolic function of patients with narrow QRS do not significantly decrease.

Objective To evaluate the effect of septal flash (SF) on left ventricular function and systolic synchrony in patients with complete left bundle branch block (CLBBB) and preserved left ventricular ejection fraction (LVEF) by two-dimensional speckle-tracking imaging (2D-STI).Methods Sixty CLBBB patients with preserved LVEF were selected,and 30 healthy individuals serving as control group.The SF of CLBBB patients were evaluated using 2D-STI,and the CLBBB patients were categorized into two groups (SF group and NSF group) based on the present SF.Conventional echocadiography and 2D-STI were performed for all individuals.Results ①SF was present in 53.3％ of CLBBB patients with preserved LVEF and was not present in control group.②LV longitudinal peak stain of global (LS-G) in SF group was lower than those in both control group and NSF group (P ＜0.05),and there was no significant difference between control group and NSF group (P ＞0.05).③Compared with control group,there were significant increase of left atrial dimension and Mitral E/e'and decrease in mitral E/A and mitral e'in SF group and NSF group (P ＜0.05),while there was no significant difference between SF group and NSF group (P ＞0.05).④There was an increase in standard deviation of time to peak systolic strain for the 18 LV segments (LV-SDt) in SF group and NSF group,and the LV-SDt in SF group was higher than that in NSF group (P ＜0.01).Conclusions SF is present in 53.3 ％ of CLBBB patients,patients of CLBBB with SF have lower left ventricular systolic function and systolic synchrony.