Electrogram organization predicts left atrial reverse remodeling after the restoration of sinus rhythm by catheter ablation in patients with persistent atrial fibrillation.

BACKGROUND

Despite the informative nature of atrial fibrillation (AF) electrograms, electrophysiological aspects of predicting reversal of structural remodeling of the left atrium (LA) have not been evaluated.

OBJECTIVES

To identify predictors of reverse remodeling after restoration of sinus rhythm by catheter ablation in patients with persistent AF.

METHODS

This study included 90 patients with persistent AF and enlarged LA (left atrial volume indexed to body surface area [LAVi] ≥32 mL/m(2)). LAVi was measured by echocardiography before ablation and 12 months after sinus rhythm restoration. We divided 73 (81%) patients free from recurrences into 2 groups according to reduction in LAVi: responders, reduction ≥23% (n = 35); nonresponders, reduction <23% (n = 38). Serological testing and electrophysiological characteristics on electrocardiogram and magnetocardiogram were analyzed.

RESULTS

LAVi decreased from 43 ± 12 to 27 ± 7 mL/m(2) in responders and from 37 ± 8 to 33 ± 8 mL/m(2) in nonresponders. Higher LAVi at baseline (P = .01), lower age (59 ± 7 years vs 63 ± 7 years; P <.05), higher brain natriuretic peptide level (median = 92, interquartile range [IQR] = 98 pg/mL vs median = 60, IQR = 64 pg/mL; P = 0.01), higher atrial natriuretic peptide level (median = 73, IQR = 74 pg/mL vs median = 54, IQR = 70 pg/mL; P = .02), and higher organization index of AF signals (0.51 ± 0.11 vs 0.42 ± 0.09; P = .0001) were observed in responders. There was a linear correlation between organization index and % reduction in LAVi (R = 0.63; P <.0001). Multiple linear regression analysis showed relations between reverse remodeling and age (β = -0.28; P = .002), atrial natriuretic peptide level (β = 0.21; P = .03), and organization index (β = 0.53; P <.0001).

CONCLUSIONS

Electrogram organization was a robust predictor of reverse remodeling of the enlarged LA after sinus rhythm restoration by catheter ablation in patients with persistent AF.