The Evaluation Of The Specialty Of Right Bundle Branch Obstruction Ventricular Dyssynchrony By Velocity Vector Imaging

Objective: To direct the optimization of clinical cardiac resynchronization therapy by researching the ventricular systolic dyssynchrony in patients with right bundle branch using the technology of velocity vector imaging.Methods: Twenty patients with complete right bundle branch block coming to the Qingdao University Affiliated Hospital were selected from Dec.2014 to Dec.2016 as a test group and twenty healthy volunteers who matched the age and sex of the test group were selected as the control group.To measure the data of the test subject by two kinds of measurement methods: firstly,measure with conventional ultrasound: Left atrial diameter,Left ventricular end diastolic diameter,Left ventricular end-diastolic volume,Left ventricular end-diastolic diameter,Left ventricular systolic volume,Ejection fraction,Sm(Left ventricular basement),E/A,Mitral regurgitation;Right atrial diameter,Right ventricular transverse diameter,Right ventricular outflow tract diameter,Sm(Right ventricular septal base),E/A,Tricuspid regurgitation.Secondly;measure with velocity vector imaging: Left ventricular short axis section 16 section radial strain peak time(Tsr),Circumferential strain peak time(Tsc),Rotation angle peak time(Tra),Right ventricular septum and free wall of the basal,middle,apical segment of the 6 segments of the strain(contraction)speed peak time(Tsl).The peak time difference of each segment of each experiment(Tsr-SD?Tsc-SD?Tra-SD?Tsl-SD)was calculated and compared.Results: 1.Compared with the control group,the left ventricular data measured by conventional ultrasound were not different(no statistically significant,P>0.05).The E/A value and tricuspid regurgitation rate of right ventricular were different(statistically significant,P<0.05).2.Compared with the control group,the Tsc-SD and Tra-SD of left ventricular were statistically significant(P<0.05)and the Tsr-SD was not statistically significant(P>0.05).3.Application of VVI for data measurement showed that,the Tsc and Tra of left ventricular in the CRBBB group were first located at the posterior interval and the last on the side wall.The Tsc and Tra of left ventricular in the control group were first located at the anterior septum and the last posterior wall.4.The Tsl of right ventricular in the CRBBB group was first located in the middle of the interventricular septum,the lastin the free wall basal segment.In the control group,the Tsl of right ventricular was first located in the basal segment of the compartment,and the last at the apical segment of the free wall.5.The order of left ventricular peak contraction: CRBBB group originating the posterior interval,along the clockwise and counterclockwise direction in two directions up to the peak,and finally reach the side wall;control group originating the front interval,along the clockwise up to the peak,and finally arrived Under the back wall.The order of right ventricular peak contraction:CRBBB group was from the middle of the interventricular septum,to interventricular septal segment,ventricular septal base,interventricular septal apex,free wall apical segment,free wall midline,and ultimately reach the free wall basal segment;The control group was from the basal segment of the compartment,to the basal segment of the compartment,the interventricular septal segment,the interventricular septal segment,the free wall basal segment,the middle of the free wall,and finally reached the free wall apical segment.Conclusion: 1.CRBBB patients with normal right ventricular systolic function,reduced diastolic function.The circumferential strain and rotation angle strain of left ventricle were not synchronized(P<0.05),and the order of the peak contraction was different from that of healthy people.2.Conventional ultrasound can not be found in patients with CRBBB left ventricular dyssynchrony.Velocity vector imaging can evaluate the myocardial motion synchronization of the patients with complete right bundle branch block.3.CRBBB patients with right ventricular contractions are not synchronized or delayed,and the order of the peak contraction is different from healthy people.