Objective       To investigate the effect of sevoflurane on the incidence of atrial fibrillation in patients undergoing heart valve replacement and the possible mechanism.        Methods       From May 2011 to August 2013

48 patients with mitral stenosis accompanied by atrial fibrillation (ASA Ⅱ-Ⅲ) due to chronic rheumatic heart disease

who underwent mitral valve replacement under light hypothermia and cardiopulmonary bypass (CPB) with general anesthesia

were randomly divided into experimental group (n=24) and control group (n=24). All patients were administrated with 0.1 mg/kg midazolam

0.3 mg/kg etomidate

5 μg/kg fentanyl

and 0.15 mg/kg vecuronium bromide by i.v. injection. Anesthesia was maintained with 1.0%~3.0% sevoflurane in the experimental group and 1.0%~3.0% isoflurane in the control group

and meanwhile

fentanyl and vecuronium bromide were intermittently injected according to needs. The incidence of atrial fibrillation was recorded during the operation and in the postoperative 24 h. The serum levels of serum C-reactive protein (CRP) and transforming growth factor β1 (TGF-β1) were detected by ELISA before anesthesia induction

and at 6 h and 24 after CPB.        Results       The incidence (16.7%) of atrial fibrillation in the experimental group was significantly lower than that (62.5%) in the control group (P0.05). CRP and TGF-β1 were significantly elevated before anesthesia induction and at 6 h after CPB in the 2 groups

but gradually declined at 24 h after CPB. However

the changes of serum CRP and TGF-β1 in the experimental group were more gentle than those in the control group

and the difference had statistical significance (P0.05).        Conclusion       Sevoflurane reduces the incidence of atrial fibrillation in the patients with mitral stenosis accompanied by atrial fibrillation during and after mitral valve replacement

which may be related with the inhibition of CRP and TGF-β1 expressions.