IMPAIRED LEFT ATRIAL MECHANICAL FUNCTION AFTER CARDIOVERSION - RELATION TO THE DURATION OF ATRIAL-FIBRILLATION

Objectives. We hypothesized that the time course of the recovery of at rial systolic function may be related to the duration of atrial fibril lation before cardioversion and sought to study nonin vasively the rec overy of left atrial mechanical function utilizing serial transthoraci c Doppler studies. Background. Recovery of atrial mechanical function may be delayed for several weeks after successful cardioversion of atr ial fibrillation to sinus rhythm. Methods. After successful cardiovers ion, 60 patients with atrial fibrillation of brief (less than or equal to 2 week, 17 patients), moderate (>2 to 6 weeks, 22 patients) or pro longed (>6 weeks, 21 patients) duration were followed up with serial t ransmitral pulsed Doppler echocardiography immediately (60 patients) a nd at 24 h (45 patients), 1 week (41 patients), 1 month (31 patients) and >3 months (30 patients) after cardioversion. Results. Atrial mecha nical function is greater immediately and at 24 h and 1 week after car dioversion in patients with ''brief'' compared with ''prolonged'' atri al fibrillation. In all groups, atrial mechanical function increases o ver time, ultimately achieving similar levels. Full recovery of atrial mechanical function, however, is achieved within 24 h in patients wit h brief atrial fibrillation, within 1 week in patients with moderate d uration atrial fibrillation and within 1 month in patients with prolon ged atrial fibrillation. Conclusions. Recovery of left atrial mechanic al function is related to the duration of atrial fibrillation before c ardioversion. These findings have important implications for assessing the early hemodynamic benefit of successful cardioversion.