Left atrial appendage ligation in patients with atrial fibrillation leads to a decrease in atrial dispersion

Background: left atrial appendage (laa) exclusion has been performed in patients with atrial fibrillation (af) to prevent thrombus formation and subsequent cardioembolic events. left atrial electrical remodeling is a recognized factor in the recurrence of af. the effects of laa exclusion on p-wave characteristics and left atrial electrical remodeling have not been well described. the purpose of this study was to evaluate the effect of laa ligation on p-wave morphology in patients with af.methods and results: fifteen patients who were in sinus rhythm during the laa ligation procedure were included in the study. we evaluated the p-wave characteristics,including p-wave duration,p-wave amplitude,pq interval,and p-wave dispersion,before and after ligation. eleven patients had paroxysmal af and 4 patients had persistent af (12 male patients and 3 female patients). p-wave duration immediately after ligation was significantly shorter compared with baseline in all limb leads except lead avr (p<0.05). p-wave amplitude immediately after ligation was significantly greater compared with baseline in inferior leads; however,p-wave amplitude after 1 to 3 months was significantly lower compared with immediately after ligation. pq interval immediately after ligation was significantly shorter compared with baseline (p=0.01),and p-wave dispersion after 1 to 3 months was significantly shorter compared with baseline (p=0.02).conclusions: laa exclusion produces consistent p-wave changes consistent with decreased atrial mass and decreased atrial dispersion that may represent reverse electrical atrial remodeling. this is a potential mechanism to explain the role of laa ligation in maintaining sinus rhythm in patients with af. © 2015 the authors. published on behalf of the american heart association,inc.,by wiley blackwell.