Efficacy of irbesartan on preventing recurrence of atrial fibrillation and on improving left atrial function

Objective To evaluate the efficacy of irbesartan in maintenance of sinus rhythm after cardioversion of atrial fibrillation(Af)and its influence on left atrial function.Methods 98 patients with persistent Af(7 days) were randomly divided into two groups after cardioversion using either antiarrhythmic medicines or synchronized direct currnt.Two groups of patients were compared.Group Ⅰwas teated with amiodarone 0.2 qd for 6 months.GroupⅡ was treated with amiodarone 0.2 qd plus irbesartan 150mg qd in the same period.During 6 months of follow-up,electrocardiogram and/or 24-hour holter recording were performed for detection of recurrence of Af in the first week,second week,first month,second month,fourth month and sixth months.The echocardiography examinations were performed on the next day and 6 months after cardioversion to evaluate changes in left attial function.Results After 6 months of follow-up,there were 15 patients(34.9 %) with recurrence of Af in group Ⅰ,while only 6 cases(13.6 %) of Af recurrence were found in group Ⅱ.There was a significant difference between the two groups(P0.05).The left atrial diameter(LAD,mm) measured by echocardiogrphy on the next day and 6 months after cardioversion in group Ⅱ was(42±12)mm and(34±11)mm respectively,with a significant reduction(P0.01).While in group Ⅰ,LAD did not show any significant reduction after six months(P0.05).Conclusion Combination of irbesartan and amiodarone is more effective in maintenance of sinus rhythm after cardioversion of Af than amiodarone alone.Long term treatment of irbesartan may reverse LA enlargement,decrease LA pressure and prevent the recurrence of Af.