Background: Until now, no clinically useful indicators have existed that predict the transition from paroxysmal to persistent atrial fibrillation (AF).
Hypothesis: The current prospective study was conducted for identifying predictors of progression to persistent AF over the long term.
Methods: We studied 102 consecutive patients (mean age: 55 +/- 10 years: 75 men and 27 women) diagnosed with paroxysmal AF. Standard 12-lead electrocardiography, echocardiography, and P-wave-triggered signal-averaged electrocardiography (P-SAECG) were performed on all patients at the time of their entry into the study.
Results: The mean follow-up period was 61 +/- 13 months. Group 1 (n = 66) comprised patients in whom paroxysmal AF did not progress to persistent AF, and Group 2 (n = 36) comprised those who developed persistent AF. In Group 2 the patients were significantly older, and P-wave dispersion, filtered P-wave duration (FPD), and left atrial dimension were significantly higher than in Group 1 (p < 0.05). The root mean square voltage for the last 30 ms of the filtered P-wave was also significantly lower in Group 2 (p < 0.05). Multivariate logistic regression analysis using these five factors identified left atrial dimension (odds ratio [OR] 2.29; 95% confidence interval [CI] 1.16-4.54; p = 0.02) and FPD (OR 2.71; 95% CI 1.78-4.13; p < 0.01) as independent predictors of transition to persistent AF. Left atrial dimension > or = 40 mm predicted progression to persistent AF with a sensitivity of 64%, specificity of 76%, positive predictive value of 59%, negative predictive value of 79%, and an accuracy of 71%. An FPD > or = 150 ms predicted persistent AF with a sensitivity of 81%, specificity of 91%, positive predictive value of 88%, negative predictive value of 90%, and an accuracy of 87%. Filtered P-wave duration was a significantly more sensitive and specific predictor than left atrial dimension (p < 0.05).
Conclusion: We conclude that FPD is a clinically useful predictor of progression from paroxysmal to persistent AF over the long term.