Abstract 13305: The Effect of Atrial Fibrillation Ablation on the Function of Left Atrium: Investigation Using Multi-Detector Computed Tomography
Effect of atrial fibrillation (AF) ablation on left atrial (LA) function is still controversial. We measured LA volumes using multi-detector computed tomography (MDCT) which has excellent spatial and temporal resolution to estimate LA function.
Methods: We enrolled consecutive 115 AF patients (92 paroxysmal and 23 persistent) undergoing AF ablation and performed with 64-slice MDCT in sinus rhythm at baseline and 3 months after the procedure. AF ablation included pulmonary vein isolation (PVI) in all patients and additional LA ablation in patients who had inducible and/or continuous AF or atrial tachycardia after PVI. To clarify the intensity of additional LA ablation, we counted the number of additional LA ablation lesions including LA roof line, mitral isthmus, and complex fractionated atrial electrocardiogram in each patient.
Results: Maximum and minimum LA volumes decreased after AF ablation (Pre- vs. Post-ablation, 59.0 ± 20.4 to 53.3 ± 16.7 cm3, p = 0.001 and 33.5 ± 16.5 to 30.5 ± 13.6 cm3, p = 0.013). LA emptying fraction (LAEF) improved in persistent AF patients (32.7 ± 11.4 to 39.1 ± 11.5%, p = 0.006), but got worse significantly in paroxysmal AF patients (47.4 ± 11.8 to 44.9 ± 10.6%, p = 0.037). The changes in LAEF from baseline to post ablation was significantly correlated with type of AF (paroxysmal vs. persistent, - 2.6 ± 11.6 vs. 6.4 ± 10.2, p = 0.0009), the number of additional LA ablation lesions (Figure1), and baseline LAEF (Figure2). The multivariate analysis revealed that increased number of additional LA ablation lesions and baseline good LAEF were independently associated with deterioration of LAEF after AF ablation.
Conclusions: After AF ablation, remodeling of LA improved significantly. However, deterioration of LAEF was observed in some patients, and pre-ablation small AF burden (paroxysmal AF and good LAEF) and the intensive LA ablation might be related to it.
- © 2010 by American Heart Association, Inc.