EPA pretreatment prevents the electrical remodeling of rapidly-paced atria. An 8-h pacing period significantly shortened the atrial ERP at BCLs of 100 and 150 msec in the control group. Treatment with EPA or pitavastatin prevented these changes. Before pacing, ERPs significantly differed between BCLs of 100 and 150 msec. The 8-h rapid pacing period eleminated this difference in control mice, but had no influence on the mice in the EPA and pitavastatin groups. Data are presented as the mean + standard error of the mean. #P<0.05 and *P<0.01 as indicated. BCL, basic cycle length; EPA, eicosapentaenoic acid; ERP, effective refractory period.