Background: Changes in mitral inflow and pulmonary venous flow after electrical cardioversion (ECV) in patients with persistent atrial fibrillation (AF) were showed in many former studies. In our study we investigated the effects of ECV on diastolic parameters by using tissue Doppler imaging (TDI) in patients with persistent AF. Methods: Forty-one (24 women) consecutive patients underwent successful elective ECV for nonvalvular persistent AF, and maintained sinus rhythm for 1 month were enrolled to the study. Transthoracic echocardiography was applied to all patients before, 24 hours after and 1 month after ECV. Mitral annular TDI parameters were also measured with mitral inflow, pulmonary venous flow, and other standard echocardiographic measurements. Results: No differences in peak myocardial early velocity (Em), deceleration time of Em, and myocardial isovolumic relaxation time measured from mitral lateral annulus before, 24 hours after, and one month after ECV were found. Peak myocardial late velocity measured 24 hours after ECV increased significantly at the end of 1 month. Conclusion: There were not any changes in LV diastolic function except restoration of atrial mechanical contraction following ECV in patients with persistent AF.