AIMS: Initial clinical studies of pulsed field ablation (PFA) to treat atrial fibrillation (AF) indicated a >90% durability rate of pulmonary vein isolation (PVI). However, these studies were largely conducted in single centres and involved a limited number of operators. We aimed to describe the electrophysiological findings and outcomes in patients undergoing repeat ablation after an initial PF ablation for AF. METHODS AND RESULTS: In the MANIFEST-REDO study, we investigated patients who underwent repeat ablation due to clinical recurrence-AF or atrial tachycardia (AT)-following first-ever PVI with a pentaspline PFA catheter (Farawave, Boston Scientific Inc.). At 22 centres, 427 patients (age 64 ± 11 years; 37% female) were included. Of note, the recurrent arrhythmia leading to the repeat ablation was paroxysmal AF (51%), persistent AF (30%), or AT (19%). At the repeat procedure, the PV reconnection rates were 30% (left superior pulmonary vein), 28% (left inferior pulmonary vein), 33% (right superior pulmonary vein), and 32% (right inferior pulmonary vein). In 45% of patients, all PVs were durably isolated at the beginning of the repeat procedure, with the previous use of any imaging or mapping modality being univariately associated with durable PVI. After a post-redo follow-up period of 284 (90-366) days, the primary effectiveness endpoint (freedom from documented AF/AT lasting ≥30 s after 3-month blanking without class I/III antiarrhythmic drugs or symptoms) was achieved in 65% of patients, with significant differences between groups (PAF 65% vs. PersAF 56% vs. AT 76%; P = 0.04). Persistent AF as recurrent arrhythmia after the initial PFA ablation predicted AT/AF recurrence after repeat ablation [hazard ratio 1.241 (95% confidence interval 1.534-1.005); P = 0.045]. The procedural complication rate was 2.8%. CONCLUSION: In repeat procedures for AF/AT performed after an index procedure with PFA for AF, PV reconnections are not uncommon. Repeat procedures can be performed safely and with an acceptable subsequent success rate.

• Keywords
• Atrial fibrillation, Atrial tachycardia, Electroporation, Pulmonary vein isolation, Pulsed field ablation,
• MeSH
• Action Potentials MeSH
• Time Factors MeSH
• Electrophysiologic Techniques, Cardiac MeSH
• Atrial Fibrillation * surgery   physiopathology   diagnosis   MeSH
• Catheter Ablation * adverse effects   methods   MeSH
• Middle Aged MeSH
• Humans MeSH
• Recurrence MeSH
• Reoperation MeSH
• Risk Factors MeSH
• Aged MeSH
• Heart Rate MeSH
• Tachycardia, Supraventricular * surgery   physiopathology   diagnosis   MeSH
• Pulmonary Veins * surgery   physiopathology   MeSH
• Treatment Outcome MeSH
• Check Tag
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Multicenter Study MeSH

Pulsed field ablation uses irreversible electroporation to interrupt cellular membranes and induce myocyte apoptosis. Reversible electroporation has been used in other specialties, but its utility in cardiac ablation is unknown. Here, a 69-year-old woman undergoing repeat ablation for atypical atrial flutter presented with extensive scar after cardiac surgery (including MAZE) and previous ablation, leading to a macro re-entry circuit. To minimize superfluous lesions and further arrhythmia, we used a single pulse confirming the isthmus location, with cessation of the arrhythmia. As a conclusion, reversible electroporation may be used to test areas of interest prior to irreversible lesion creation.

• Keywords
• Atrial tachycardia, catheter ablation, novel mapping technique, pulsed field ablation, reversible electroporation,
• Publication type
• Journal Article MeSH
• Case Reports MeSH