Real-time Three-dimensional Echocardiography in Evaluating Left Atrial Systolic Function in Patients with Different Pacing Site of Right Ventricle / 中国医学影像学杂志

ABSTRACT

PurposeTo evaluate the effect of right ventricular septum (RVS) and right ventricular apex (RVA) pacing on the left atrial systolic function in patients with atrioventricular block by using real-time three-dimensional echocardiography (RT-3DE).Materials and Methods Fifty-one patients with atrioventricular block who were candidates for implanted atrioventricular sequential pacemaker were randomly divided into RVS group (n=31) and RVA group (n=20). The minimum left atrium volume (LAVmin), maximum left atrium volume (LAVmax), and left atrium volume before contraction (LAVprep) were measured by RT-3DE at pre-operation, the 1st month, 3rd month, 6th month, and 12th month after pacemaker implantation. Accordingly, the left atrial total ejection fraction (LATEF) and the left atrial active ejection fraction (LAAEF) were calculated.Results The LAVmin at the 3rd month, 6th month, 12th month after implantation were significantly lower than that at the 1st month and pre-operation in both groups (RVA groupt=2.97 and 2.74,P<0.05; RVS groupt=3.24 and 2.86,P<0.05). LAVprep at the 6th month, 12th month in RVA group, and LAVprep at the 3rd month, 6th month, 12th month in RVS group reduced when compared with that of pre-operation (RVA groupt=3.20,P<0.05; RVS groupt=2.71,P<0.05). LATEF and LAAEF in both groups at the 3rd month, 6th month, 12th month increased when compared with that of pre-operation (RVA groupt=2.87 and 9.68,P<0.05; RVS groupt=3.56 and 8.22,P<0.05). The LATEF and LAAEF in RVS group at the 6th month and 12th month after implantation were significantly larger than that in RVA group at the same time (t=2.90, 5.22, 3.03 and 3.55, P<0.05).Conclusion Atrioventricular sequential pacing is helpful to recovering the left atrial systolic function in patients with atrioventricular block. Compared with RVA pacing, RVS pacing is able to increase LATEF and LAAEF more greatly.