| Abstract: | Atrial Substrate Properties in Chronic AF Patients with LASEC. Background: The atrial substrate in chronic atrial fibrillation (AF) patients with a left atrial spontaneous echo contrast (LASEC) has not been previously reported. The aim of this study was to investigate the atrial substrate properties and long‐term follow‐up results in the patients who received catheter ablation of chronic AF. Methods: Of 36 consecutive patients with chronic AF who received a stepwise ablation approach, 18 patients with an LASEC (group I) were compared with 18 age‐gender‐left atrial volume matched patients without an LASEC (group II). The atrial substrate properties including the weighted peak‐to‐peak voltage, total activation time during sinus rhythm (SR), dominant frequency (DF), and complex fractionated electrograms (CFEs) during AF in the bi‐atria were evaluated. Result: The left atrial weighted bipolar peak‐to‐peak voltage (1.0 ± 0.6 vs 1.6 ± 0.7 mV, P = 0.04), total activation time (119 ± 20 vs 103 ± 13 ms, P < 0.001) and DF (7.3 ± 1.3 vs 6.6 ± 0.7 Hz, P < 0.001) differed between group I and group II, respectively. Those parameters did not differ in the right atrium. The bi‐atrial CFEs (left atrium: 89 ± 24 vs 92 ± 25, P = 0.8; right atrium: 92 ± 25 vs 102 ± 3, P = 0.9) did not differ between group I and group II, respectively. After a mean follow‐up of 30 ± 13 month, there were significant differences in the antiarrhythmic drugs (1.1 ± 0.3 vs 0.7 ± 0.5, P = 0.02) needed after ablation, and recurrence as persistent AF (92% vs 50%, P = 0.03) between group I and group II, respectively. After multiple procedures, there were more group II patients that remained in SR, when compared with group I (78% vs 44%, P = 0.04). Conclusion: There was a poorer atrial substrate, lesser SR maintenance after catheter ablation and need for more antiarrhythmic drugs in the chronic AF patients with an LASEC when compared with those without an LASEC. (J Cardiovasc Electrophysiol, Vol. pp. 1‐8) |
