P-wave characteristics after electrical external cardioversion: predictive indexes of relapse

Usefulness of P-wave signal averaging to predict atrial fibrillation recurrences after electrical cardioversion

BACKGROUND

Accurate markers of atrial fibrillation (AF) recurrences after electrical cardioversion (ECV) are lacking. This study was conducted to assess the value of P-wave signal averaging (SAPW) for predicting AF recurrences in a nonselected patients population submitted to ECV.

METHODS

A total of 133 patients (107 males, 26 females, mean age 66 ± 9 years) were included after successful ECV for persistent AF (mean duration of AF 3.6 ± 2.2 months). The mean ejection fraction (EF) was 60 ± 9%, and left atrial (LA) diameter was 44 ± 6 mm. SAPW ECG was obtained immediately after ECV and patients were prospectively followed.

RESULTS

During a mean follow-up of 8.9 ± 5.2 months, AF recurrences occurred in 40.6% (54/133). No SAPW parameters was statistically different between the group of patients with and the group without recurrences. Recurrences were less often observed in patients with a total P-wave duration <150 ms (16/52 or 31% vs 38/81 or 47% in patients with total P-wave duration ≥150 ms) but the difference was not statistically different (P = 0.07). P-wave duration was correlated with age (r = 0.32; P < 0.001) and left atrial diameter (r = 0.19; P = 0.02). Age, sex, structural heart disease, amiodarone therapy, or hypertension were not associated with AF recurrences but patients without recurrences had a shorter AF duration (P = 0.001) and more often had a history of previous ablation (P = 0.027).

CONCLUSION

In this unselected "real-life" group of patients submitted to ECV for persistent AF, none of the SAPW parameters, including total filtered P-wave duration, was able to predict AF recurrences.