Study of left ventricular diastolic function in patients with DDD pacemaker implantation for sick sinus syndrome during atrioventricular conduction and right ventricular apex pacing mode

Abstract

Objective To analyze the left ventricular (LV) diastolic function parameters of patients with sick sinus syndrome (SSS) and DDD pacemaker implantation during atrioventricular conduction (AVC) and right ventricular apex pacing (RVAP) mode. Methods Forty-six consecutive patients with SSS who had undergone DDD pacemaker implantation were studied. Fifty volunteers were selected as control group.Changing from AVC to RVAP mode, the acute effect on echocardiographic left ventricular diastolic function parameters, including mitral inflow PW parameters, mitral annulus tissue Doppler imaging parameters, left atrial volume index, and LV/apical/basal untwist parameters were measured. And all subjects were classified into normal diastolic function or three degrees of LV diastolic dysfunction. Results Compared with control group, both AVC and RVAP mode of patients with DDD pacemaker implantation resulted in the worsening of LV diastolic function as shown by (1) prolonged deceleration time of E wave, decreased descending slope of E wave, as well as decreased early diastolic velocity at the septal mitral annulus, (2) the decrease of LV/basal/apical untwist velocity, (3) the increase in the degree of diastolic dysfunction. Conclusions In patients with DDD pacemaker implantation, both AVC and RVAP mode are associated with the deterioration of LV diastolic function, which is particularly obvious in RVAP mode. Key words: Echocardiography; Cardiac pacemaker, artificial; Ventricular function, left