Clinical trial NCT06657170: Hidden Slow Conduction Ablation for Recurrent Atrial Fibrillation: Unmasking the Arrhythmogenic Substrate (Unmask-AF)
Official title: Hidden Slow Conduction Ablation for Recurrent Atrial Fibrillation: Unmasking the Arrhythmogenic Substrate
Study type: INTERVENTIONAL
Overall status: NOT_YET_RECRUITING
Phase: NA
Conditions: Atrial Fibrillation
Keywords: Catheter Ablation
Re-do Procedures
Hidden Slow Conduction
Functional Substrate Ablation
Lead sponsor: Centro Medico Teknon
Sponsor class: OTHER
First posted: 2024-10-24
Enrollment: 212
Sex: ALL
Minimum age (years): 40
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: This is a two-arm, single-center, randomized controlled trial
Primary purpose: TREATMENT

Brief summary: Over recent years, pulmonary vein isolation (PVI) procedures have demonstrated progressively enhanced efficacy and safety, resulting in a substantial increase in the number of atrial fibrillation ablations, not only as a first-line treatment but also for repeat procedures. However, there is still a notable lack of randomized evidence in this area, which limits guidance and decision-making in clinical practice. Recently, the investigators found that employing short-coupled atrial extrastimuli revealed highly fragmented or double atrial evoked electrograms (EGMs) in AF patients, termed as hidden slow conduction (HSC). Identifying HSC sites may provide insight into the early identification of the arrhythmogenic substrate, offering a potential target for ablation This multi-center, prospective, randomized, controlled trial will include two arms: one investigational (PV reconnection + HSC) and one control (PV reconnection). All the subjects will be followed for 12 months after the ablation procedure.

The aim of our study is to investigate the impact of ablating HSC sites on arrhythmia recurrence in repeat ablation procedures. The hypothesis is that the additional ablation of HSC zones may improve the freedom from atrial arrhythmia recurrence after repeat ablation procedure.


Eligibility criteria: Inclusion Criteria:

* Recurrent paroxysmal AF (continuous AF episode lasting longer than 30 s but terminating spontaneously or with intervention within 7 days of onset), recurrent persistent AF (continuous AF episode lasting longer than 7 days but \< 1 year) and recurrent long standing persistent AF (continuous AF ≥1 year in duration, in patients where rhythm control management is being pursued)
* Previous PVI procedure
* Age \> 40 years
* Willing and capable of providing consent
* Able and willing to comply with all follow-up testing and requirements

Exclusion Criteria:

* Additional left atrial ablations during the previous procedures (es. posterior wall isolation, anterior line, roof line, CFAE and others)
* Acute illness, active systemic infection, or sepsis
* Presence of intracardiac thrombus, myxoma, tumor, interatrial baffle or patch or other abnormality that precludes catheter introduction or manipulation.
* Severe mitral regurgitation
* Women who are pregnant, lactating, or who are planning to become pregnant during the course of the clinical investigation

Primary outcomes:
measure: Atrial arrhythmias recurrence
timeFrame: up to 12 moths
Secondary outcomes:
measure: Burden of atrial arrhythmias
timeFrame: up to 12 moths
measure: incidence of periprocedural complications (pericardial effusion)
timeFrame: up to 12 months
measure: Use of antiarrhythmic drugs
timeFrame: up to 12 months
measure: incidence of periprocedural complications (peripheral complication)
timeFrame: up to 12 moths
measure: incidence of periprocedural complications (transient ischemic attack or stroke)
timeFrame: up to 12 months
Other outcomes:
measure: Concentration of intramyocardial fat (inFAT) into the HSC points
timeFrame: up to 12 months
measure: Procedure features
timeFrame: up to 12 months
measure: Atrial arrhythmias first recurrence
timeFrame: up to 12 months
measure: Left atrial wall thickness (LAWT) measurement into the HSC points
timeFrame: up to 12 months
measure: procedure features
timeFrame: up to 12 months
measure: procedure features
timeFrame: up to 12 months
measure: procedure features
timeFrame: up to 12 months
measure: procedure times
timeFrame: up to 12 months
Locations:
Study officials:
References:
citation: Pokushalov E, Romanov A, De Melis M, Artyomenko S, Baranova V, Losik D, Bairamova S, Karaskov A, Mittal S, Steinberg JS. Progression of atrial fibrillation after a failed initial ablation procedure in patients with paroxysmal atrial fibrillation: a randomized comparison of drug therapy versus reablation. Circ Arrhythm Electrophysiol. 2013 Aug;6(4):754-60. doi: 10.1161/CIRCEP.113.000495. Epub 2013 Jun 7.
citation: Saglietto A, Falasconi G, Soto-Iglesias D, Francia P, Penela D, Alderete J, Viveros D, Bellido AF, Franco-Ocana P, Zaraket F, Turturiello D, Marti-Almor J, Berruezo A. Assessing left atrial intramyocardial fat infiltration from computerized tomography angiography in patients with atrial fibrillation. Europace. 2023 Dec 6;25(12):euad351. doi: 10.1093/europace/euad351.
citation: Silva Garcia E, Lobo-Torres I, Fernandez-Armenta J, Penela D, Fernandez-Garcia M, Gomez-Lopez A, Soto-Iglesias D, Fernandez-Rivero R, Vazquez-Garcia R, Acosta J, Bisbal F, Cano-Calabria L, Berruezo A. Functional mapping to reveal slow conduction and substrate progression in atrial fibrillation. Europace. 2023 Nov 2;25(11):euad246. doi: 10.1093/europace/euad246.