Utility of Pharmacologic Conversion of Persistent Atrial Fibrillation by Amiodarone as a Predictor of Outcome After...

Restoration and maintenance of sinus rhythm (SR) before pulmonary vein isolation (PVI) by antiarrhythmic drug (AAD) therapy can lead to a better outcome in persistent atrial fibrillation (AF). It is unknown, however if pharmacologic conversion by amiodarone loading itself, compared to the need for additional electrical cardioversion (ECV), predicts a better outcome of PVI. Furthermore, it remains controversial whether subsequent AF episodes occurring while on amiodarone before PVI, have any predictive value. Our aim was to assess whether amiodarone response before the procedure shows predictive value in patients with persistent AF undergoing PVI.

We retrospectively collected data from consecutive patients with persistent AF who underwent PVI between 2013 and 2023, and who received temporary amiodarone therapy, with or without ECV to restore and maintain sinus rhythm before the intervention. A total of 353 patients (30% female, mean age: 63.76 ± 9.27 years) were included. Conversion to sinus rhythm was achieved solely by amiodarone therapy (AmioConv) in 96 patients (27%), while 257 patients (73%) required additional ECV as well. There were no differences between the two groups in terms of comorbidities, CHADS-VASc score (2.46 ± 1.43 vs. 2.26 ± 1.48, p = 0.27), or echocardiographic parameters, but the AmioConv group had a shorter history of AF (2.22 ± 2.96 years vs. 3.74 ± 4.64 years, p < 0.01). During a mean follow-up of 3.48 ± 2.32 years after PVI, patients in the AmioConv group less frequently experienced AF recurrences (41% vs. 56%, p = 0.016) and had significantly longer mean recurrence-free survival (5.21 ± 0.54 vs. 3.6 ± 0.35 years, p < 0.01), compared to the ECV group. The lack of pharmacologic conversion by amiodarone therapy (need for ECV) was found to be the only independent predictor of post PVI recurrences (adjusted HR 1.86, 95% CI 1.21-2.85, p < 0.01). On the contrary, breakthrough episodes of AF during amiodarone therapy, before ablation, were not predictive (adjusted HR 0.87, 95% CI 0.57-1.32, p = 0.51).

In patients with persistent atrial fibrillation the outcome after PVI is predicted by pharmacologic conversion during amiodarone loading, but not the reoccurrence of the arrhythmia during continued pre-ablation AAD therapy.