Factors influencing development of atrial fibrillation after implantation of cardiac pacemaker for sinus node dysfunction

Objective. The aim of this study was to evaluate factors influencing the success of atrial fibrillation treatment associated with the sick sinus syndrome after pacemaker implantation.
Methods and results. In 163 patients with sick sinus syndrome followed up after pacemaker implantation, statistical analysis showed that the recurrence of atrial fibrillation increased 2.8 times and 2.5 times when the left atrium or the right atrium, respectively, were increased by 1 cm (P=0.001). In addition, the recurrence of atrial fibrillation increased 2.5 times when the interventricular septum was thickened (P=0.007). Probability of atrial fibrillation recurrence was 2.73 times higher in the presence of grade II mitral regurgitation as compared to absent or grade I mitral regurgitation (P=0.029). The results of atrial fibrillation treatment did not significantly depend on age, gender, duration of atrial fibrillation symptoms, other cardiac structural changes, and concomitant noncardiac diseases.
Conclusions. In patients with sick sinus syndrome, the effectiveness of atrial fibrillation treatment after pacemaker implantation is influenced by enlargement of the left and the right atria, increased interventricular septum thickness, and grade II mitral regurgitation. Evaluation of echocardiographic data before pacemaker implantation has prognostic value for determining the probability of maintenance of sinus rhythm.