Spectral turbulence analysis of the signal-averaged electrocardiogram of the atrial activation as predictor of recurrence of idiopathic and persistent atrial fibrillation.
The frequency domain analysis of the P-wave signal-averaged ECG (P-SAECG) is able to identify patients at risk for lone atrial fibrillation (AF) after cardioversion to sinus rhythm. The terminal portion of the P-wave of right precordial leads on 12-lead ECG is associated with electrical abnormalities in the atria. The aim of this study was to assess the spectral turbulence analysis (STA) of the P-SAECG as a predictor of recurrence of idiopathic AF. STA was performed in 41 patients with 2 or more symptomatic episodes of idiopathic and persistent AF after successful electrical cardioversion and drug-free state (Group A), and in 25 control individuals during sinus rhythm (Group B), matched by age, gender, and P-wave duration. The orientation of the terminal portion (positive or negative) of the Z-lead was assessed as representing right precordial leads potentials. After 6 months follow-up, Group A was divided into two groups according to recurrence: G-A1--at least one recurrence (21 patients), and G-A2--no recurrence (20 patients). Fragmented electrical activity (FEA) was observed in 19 patients of G-A1 and in 2 of G-A2 (odds ratio = 85.5; p<<0.001). STA showed 90.5% sensitivity and 90.0% specificity for early recurrence of AF. After 12 months, no patients of G-A2 and 15 of G-A1 developed >3 episodes of persistent AF, being FEA observed in 13 (odds ratio = 14.6, p = 0.002). No episodes of AF were observed in Group B. Average time for recurrence of FEA positive patients (4.3 +/- 0.7 months) was significantly shorter than of G-A2 (7.4+/-0.7 months), and log-rank analysis revealed significant difference of event-free rate over time (p = 0.004). In a logistic regression model FEA, use of amiodarone and a positive terminal portion of the Z-lead of the P-SAECG were independent predictors of recurrence of idiopathic and persistent AF.
Benchimol Barbosa
Paulo Roberto
PR
Section of Cardiac Electrophysiology and Arrhythmia, Department of Cardiology, State University of Rio de Janeiro, Rio de Janeiro, Brazil. ecgar@uerj.br
de Souza Bomfim
Alfredo
A
Barbosa
Eduardo Corrêa
EC
Ginefra
Paulo
P
Helena Cardoso Boghossian
Silvia
S
Destro
Cleonilce
C
Nadal
Jurandir
J
D000638:Amiodarone / Q000627:therapeutic use; D000889:Anti-Arrhythmia Agents / Q000627:therapeutic use; D001281:Atrial Fibrillation / Q000175:diagnosis*; D016022:Case-Control Studies; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D016555:Matched-Pair Analysis; D008875:Middle Aged; D011237:Predictive Value of Tests; D012008:Recurrence; D012189:Retrospective Studies; D012815:Signal Processing, Computer-Assisted; D016019:Survival Analysis
D000889:Anti-Arrhythmia Agents; D000638:Amiodarone