Robustness analysis of processing blocks in T-wave alternans detection

Abstract

Background: Predictors of arrhythmia recurrence after catheter ablation of atrial fibrillation (AF) are still unclear. The aim of this study was to determine the relationship between dominant atrial cycle lengths (DACL) obtained from surface electrocardiogram (ECG) and clinical outcome after catheter ablation. Methods: In 21 patients (mean age, 52 ± 9 years), left atrial radiofrequency ablation was performed for paroxysmal (n = 9) or persistent (n = 12) AF. Dominant atrial cycle length was assessed before ablation from the V1 lead surface ECG using digital signal processing (filtering, subtraction of averaged QRST complexes, and power spectral analysis). All patients underwent pulmonary vein isolation (PVI). Linear ablation was performed in 12 patients. Results: Dominant atrial cycle length was significantly higher in paroxysmal (186 ± 31 milliseconds) than persistent AF (146 ± 17 milliseconds) and in PVI -only-treated patients (182 ± 33 milliseconds) than in patients who underwent additional linear ablation (149 ± 21 milliseconds). Follow-up was 11 ± 5 months. Dominant atrial cycle length was significantly greater in patients without recurrence AF (176 ± 28 vs 152 ± 31 milliseconds). Conclusions: Higher baseline fibrillatory rates are associated with recurrence AF, which suggests advanced electrical remodeling and reduced atrial refractoriness.