time to recover from atrial hormonal, mechanical, and electrical dysfunction after successful electrical cardioversion of persistent atrial fibrillation

Although transient atrial dysfunction has been reported after electrical ca rdioversion of atrial fibrillation (AF), the difference in the time to reco ver from the atrial hormonal, mechanical, and electrical dysfunction has no t been described. Thus, we evaluated the time course of recovery from atria l hormonal, mechanical, and electrical dysfunction after cardioversion in p atients with non-valvular AF. We attempted electrical cardioversion in 87 c onsecutive patients with nonvalvular AF that had persisted for greater than or equal to 6 months, and in 24 patients (28%) with maintained sinus rhyth m for greater than or equal to 6 months. To evaluate atrial hormonal, mecha nical, and electrical dysfunction in these 24 patients, we measured plasma concentration of atrial natriuretic peptide, the atrial peak velocity in tr ansmitral flow, and the ratio of peak systolic-to-diastolic pulmonary venou s flow (S/D ratio) using echocardiography, and the duration and the root me an voltage for the terminal 20 ms (LP20) of the filtered P wove using P-wav e signal-averaged electrocardiography. Atrial natriuretic peptide rapidly r eturned to baseline within 1 day after cardioversion, and maintained these levels for 6 months. Atrial peak velocity in transmitral flow and S/D ratio were significantly increased at 2 weeks, and continued to increase until 1 month, and then reached a plateau. The duration and LP20 began to recover only 6 months after cardioversion. One to 3 years after conversion, the dur ation and LP20 had nearly reached a plateau, but the latter value remained below normal. In patients with nonvalvular AF of prolonged duration, recove ry from atrial electrical dysfunction after sinus conversion took much long er than that from either atrial hormonal or mechanical dysfunction. (C) 200 0 by Excerpta Medica, Inc.