[Effects of left atrial enlargment on the recurrence of atrial fibrillation in elderly paroxysm alatrial fibrillation patients after pacemaker implantation].

Objective: To investigate the incidence of recurrent atrial fibrillation, including asymptomatic atrial fibrillation, and the effect of left atrial volume index (LAVI) on recurrence of atrial fibrillation in elderly paroxysmal atrial fibrillation patients with implanted cardiac pacemakers.

Methods: One hundred and forty eight elderly paroxysmal atrial fibrillation patients without antiarrhythmic drug therapy after car-diac pacemaker implantation were selected from January 2012 to December 2013 in this study. The baseline characteristics, echocardiography parameters, the incidence of recurrent atrial fibrillation and the burden of atrial fibrillation were recorded. The patients were divided into groups according to the burden of atrial fibrillation and the left atrial volume index. Multivariate Cox regression analysis was adopted to calculate the adjusted hazard ratio (HR) of left atrial volume index for the device-detected recurrence of atrial fibrillation and atrial fibrillation burden.

Results: During an average of 22.79 months follow-up period, 57.43% of the patients with recurrence of atrial fibrillation, 22.97% of the pa-tients with high intensity burden of atrial fibrillation, and 15.54% of the patients with asymptomatic atrial fibrillation were found. Multivariate Cox regression analysis demonstrated left atrial enlargement (LAVI > 28 ml/m) was an independent risk factor for the device-detected recur-rence of atrial fibrillation ( < 0.05) and atrial fibrillation burden ( < 0.01)respectively.

Conclusions: Left atrial volume index is an inde-pendent risk factor for the recurrence of atrial fibrillation and atrial fibrillation burden in elderly patients with paroxysmal atrial fibrillation after pacemaker implantation.