The relation between ejection fraction and mitral annulus motion before and after direct-current electrical cardioversion

Mitral annulus motion (MAM) and the relation between left ventricular eject ion fraction (EF) and MAM has been shown to differ between patients with si nus rhythm and patients with atrial fibrillation. However, it has not been investigated how the relation between EF and MAM changes on direct-current (DC) electrical cardioversion to sinus rhythm. Therefore, 31 consecutive pa tients on the waiting list for DC electrical cardioversion were examined by echocardiography before DC electrical cardioversion, and those who maintai ned sinus rhythm (13 patients) were examined again 4-8 weeks after cardiove rsion. The conversion factor (CF) (ratio EF/MAM) decreased from 8.4 +/- 1.7 before to 5.8 +/- 0.8 SD after cardioversion (P < 0.001). The EF increased slightly (P < 0.05) but the MAM had a much greater increase (P < 0.001), r esulting in the decrease in CF. There was no significant difference in CF b etween patients after cardioversion and age- and gender-matched control pat ients with sinus rhythm, indicating that CF is normalized or almost normali zed 4-8 weeks after cardioversion. This indicates that when MAM is used for investigation of the left ventricular function, and the function is expres sed as EF, the same CF as in other patients with sinus rhythm can be used 4 -8 weeks after DC electrical cardioversion.