Catheter Ablation -> Atrial Fibrillation & Atrial Flutter: -> Clinical Trials / Outcomes D-PO03 - Poster Session III (ID 48) Poster

D-PO03-199 - Left Ventricular Functional Recovery And Improvement Of Mechanical Dispersion After Atrial Fibrillation Ablation (ID 1154)


Background: It remains unknown about the mechanism accounting for left ventricular (LV) reverse remodeling (LVRR) after catheter ablation (CA) for atrial fibrillation (AF).
Objective: To examine the recovery of LV function after CA for AF and its correlations with regional heterogenity of LV contraction timing (i.e., mechanical dispersion) in patients with reduced LV ejection fraction (LVEF).
Methods: We retrospectively enrolled 148 patients who underwent first-time CA for AF and LVEF of <50%. They were evaluated by multi-detector computed tomography at baseline and 3-month after CA. Chamber sizes and function were automatically measured, and LVRR, defined as decrease in LV end-systolic volume (LVESV) of ≥20%, was evaluated. Standard deviation (SD) of time from onset of the QRS complex to the peak regional wall motion was calculated using a 16-segment model. The percentage of the SD during the cardiac cycle was expressed as a parameter of mechanical dispersion. It is a measure of how homogenous or heterogeneous the LV segments are contracting.
Results: Although there was no significant change in LV end-diastolic volume (115±46ml vs. 114±39ml, p = 0.58), reduction of LVESV (from 71±37ml to 46±34ml, p <0.001) and improvement of LVEF (from 40±9% to 62±14%, p <0.001) were observed after CA. The mechanical dispersion was inversely correlated with LVEF both at baseline and after CA (r = -0.51 and r = -0.36, both p <0.001), and we found significant decrease of the mechanical dispersion (from 11.7±6.0% to 9.0±4.8%, p <0.001) after CA. Reduction of the dispersion was larger in patients with LVRR (n = 113) than those without (3.3±7.4% vs. 0.3±4.7%, p = 0.005). Age-adjusted logistic regression analysis revealed that significant decrease in the dispersion (i.e., the best cut-off value of SD% >3.9%) was associated with LVRR (odds ratio, 3.65; 95% confidence interval, 1.32-10.2, p = 0.013).
Conclusion: There was a decrease in temporal heterogenity of LV contraction after CA for AF, and the improvement of mechanical dispersion was associated with LVRR. Rearrangement of contraction timing after restoration of SR by CA may reduce LV end-systolic deformation, resulting in LVRR.