Intraprocedural findings and outcomes of redo-procedures after voltage guided ablation of persistent atrial fibrillation

Introduction:

Pulmonary vein isolation (PVI) is the gold standard for atrial fibrillation (AF) ablation. Recently, adding voltage-guided ablation (VGA) was superior to PVI only in a randomized study. The aim of the present study was to evaluate efficacy of a redo-procedure after VGA and predicors of success in an exclusivley persistent AF cohort. 

Methods:

Persistent AF cases who received their first AF ablation using VGA and CARTO3D between January 2015 and May 2022 were included in the Erfurt AF ablation registry. Patients receiving their first redo-procedure after VGA between January 2015 and August 2022 were included in the present study. Ablation was performed using Thermocool Smarttouch SF^TM. Regular follow up included 72hour Holter ECG or device interrogation, ECG and questioning after 3 and 12 months. Primary endpoint was freedom of recurrence of AF or atrial tachycardia (AT) without drugs between 3 and 12 months follow up. Using clinical and intraprocedural data we compared the groups of patients with recurrence and such without to identify potential predictors of recurrence after reablation. 

Results:

Altogether, 676 patients received a first VGA and 77 patients were included in the analysis because of their first redo ablation thereafter (age 70±8 years, male sex in 51% and LAESVI 43±13 ml/m2, mean LVEF 54±9%). Mean interval between first and redo procedure was 20 ±17 months. During first procedure in 36% of the patients significant low voltage zones (LVZ) had been identified and ablated. During the second procedure reconnected PV were found in 45% and reconnected lines in 23% of patients. New or progressive LVZ were found in 60% of patients. Complications occurred in two patients (TIA and sinus arrest). During follow up one patient died, one patient was not able to take part in follow up because of aphasia. Altogether 47 out of 75 patients (63%) were free of recurrence off drugs and 53 out of 75 patients (71%) were free of recurrence. 

Patients with recurrence were significantly older than those without recurrence and off drugs (73±6 versus 69±9 years, p 0.04). There was a tendency for higher LAESVI in the recurrence-group (48±13 versus 40 ±12 ml /m2). No other relevant differences could be identified (table 1).

Conclusions:

Repeat ablations after VGA in persistent AF have comparatively good results and are useful. Patients with recurrence are significantly older than those without. In a large number of patients there is evidence of progressive fibrosis. However, there was also a significant rate of reconnection of previously applied lines.