Left atrial appendage anatomy and function: short term response to sustained atrial fibrillation

Objective-To determine whether there is significant atrial or atrial append age enlargement or functional remodelling as a result of one to two months of sustained atrial fibrillation, a duration similar to that experienced by patients undergoing warfarin anticoagulation before elective cardioversion . Methods-To test the hypothesis that left atrial and left atrial appendage e nlargement develop as a result of short term atrial fibrillation, serial an atomical and functional indices were measured using transoesophageal echoca rdiography (TOE) in 20 patients with recent onset atrial fibrillation (14 m en, six women; mean (SEM) age 67 (2) years). Serial TOE was performed 2.5 m onths apart in patients with sustained atrial fibrillation. Results-There was no significant change in left atrial area (23.7 cm(2) to 24.1 cm(2), p = 0.98); length (5.7 cm to 5.7 cm, p = 0.48); width (5.2 cm t o 5.2 cm, p = 0.65); volume (83 cm(3) to 87 cm(3), p = 0.51) or left atrial appendage area (7.9 cm(2) to 8.1 cm(2), p = 0.89); length (4.6 cm to 4.5 c m, p = 0.8); or width (2.5 to 2.4 cm, p = 0.87). Peak left atrial appendage velocity ejection (0.2 m/s to 0.2 m/s, p = 0.57), and presence of severe s pontaneous echo contrast in the left atrial appendage (n = 15 (75%) to n = 13 (72%)) were also not significantly different. There was no correlation b etween changes in left atrial or left atrial appendage dimensions. Conclusions-In the setting of sustained atrial fibrillation, significant le ft atrial and left atrial appendage functional and anatomical remodelling d o not occur with atrial fibrillation of a duration similar to that used for conservative anticoagulation in preparation for cardioversion.