Higher recurrence rate after ablation of persistent atrial fibrillation in patients with prolonged P-wave negativity in lead V1

Several ECG P-wave parameters, such as duration, amplitude and morphology reflect the electromechanical condition of the atria. P-wave features mainly served to identify patients prone to atrial fibrillation (AF) or to predict recurrence of paroxysmal AF after ablation.

We sought to investigate which specific features derived from the P-wave might help identify patients with persistent atrial fibrillation (peAF) unresponsive to wide circumferential pulmonary veins isolation (WPVI).

41 patients (63±10 y) with peAF (sustained duration 11±7 months) underwent a de-novo WPVI. A second WPVI was performed in patients with recurrent AF in order to provide complete PV disconnection. We defined "success" as patients who remained in sinus rhythm (SR) after one or two procedures, and "failure" otherwise. The average duration and amplitude of the P-waves on ECG lead II, and the duration and amplitude of positive and negative deflections on ECG lead V1 were extracted during SR after cardioversion at the end of the index WPVI. P-wave terminal force in V1 (PTFV1) was computed as the product of negative amplitude and duration in lead V1.

Over a mean follow-up of 32±9 months, 24 patients remained free from AF (success group), while 11 patients had AF recurrence after 2 WPVIs (failure group). Six patients were lost to follow-up or declined the second WPVI. 45% (5/11) were ON antiarrhythmic drugs (AAD) during follow-up in the failure group, while 0.04% (1/24) were ON AAD in the success group (p<0.05). Other clinical characteristics (e.g. age, body mass index, left atrial volume or duration in sustained AF) were similar. The figure displays P-wave metrics of patients ON and OFF AAD during follow-up. No significant differences were found in P-wave duration (lead II; Panel A1), in PTFV1 (Panel A2), and in duration of V1 positive deflection (Panel A3). Interestingly, the failure group displayed longer duration of the negative deflection in V1 (76±17ms) than that of the success group (68±18ms, p<0.05; Panel A4). Panel B shows that the differences remained after exclusion of patients ON AAD during follow-up. No differences were found in P-wave amplitude in lead II or in amplitude of positive and negative deflections in lead V1 (data not shown).

Our results show that prolonged negativity in lead V1, which is indicative of left atrial electromechanical remodeling, is associated with failure to restore long-term sinus rhythm after WPVI of peAF.