Evaluation Of Left And Right Atrial Synchrony In Patients With Sick Sinus Syndrome Before And After Pacemaker Implantation By Tissue Doppler Ultrasonography

Objective To evaluate the intra-and interatrial synchronization before and after pacemaker implantation in patients with sick sinus syndrome?SSS?by tissue Doppler imaging?TDI?.Methods Thirty-eight patients with SSS?SSS group?underwent pacemaker implantation.Echocardiography was performed before and after operation.Twenty-five volunteers with normal heart rate were chosen as the control group.Routine measurement of left and right atrial diameter by echocardiography.In apical four chamber view,the sample volume of TDI was located at right atrial lateral wall at tricuspid annulus,interatrial septum and left atrial lateral wall at mitral annulus.The interval time between the early diastolic wave?E wave?and the late diastolic wave?A wave??E-A_R,E-A_I,E-A_L?,and the A wave duration?A_R,A_I,A_L?were measured.The electromechanical coupling time of the above 3sites was measured within same cardiac cycle,namely the initiation of the P wave of the synchronous electrocardiogram to the starting point of A wave?P-A0_R,P-A0_I,P-A0_L?,and the starting point of the P wave to the peak point of the A wave?P-A_R,P-A_I,P-A_L?.And the right atrial electromechanical delay time:P-A0_I and P-A0_R value(T0_IR),P-A_I and P-A_R value(T_IR)were recorded.Other parameters include left atrial electromechanical delay time:P-A0_L and P-A0_I value(T0_LI),and P-A_L and P-A_I value(T_LI);interatrial electromechanical delay time:P-A0_L and P-A0_R value(T0_LR),P-A_L and P-A_R(T_LR)were recorded.Results Compared with the control group,left atrium and right atrium in SSS group enlarged before operation,E-A_R,E-A_I,E-A_L,P-A0_R,P-A0_I,P-A_R,P-A_L were prolonged,while T0_LR and T0_LI were shortened?all P<0.05?.Postoperative changes in SSS group patients included shortened E-A_R,E-A_I,E-A_L,and prolonged T0_LI,T0_LR?all P<0.05?.Compared with the control group,left atrium and right atrium in SSS group still enlarged postoperation,and the P-A_R and P-A0_I remained longer?all P<0.05?.In the control group and the SSS group,A_R,A_I and A_L in the postoperative group were shortened?all P<0.05?.The area under the ROC curve of E-A_R,E-A_I,E-A_L and P-A_R were 0.808,0.769,0.797 and0.801,respectively.When E-A_R was 158 ms,the Youden index was the largest,and its sensitivity and specificity for diagnosis of SSS were76.9%and 81.8%,respectively.Conclusions The electromechanical activities in the intra-and interatrial in SSS patients are not synchronous pacemaker implantation can improve the synchronicity of electromechanical activities in some atrium.TDI can accurately assess the synchronicity of electromechanical activities of atrial myocardium in SSS patients before and after pacemaker implantation.