COnCOmitaNt pulse field ablation based pUlmonary vein isolation and lefT atrial appendage closure – The COCONUT study

Atrial fibrillation (AF) ablation by pulmonary vein isolation (PVI) and left atrial appendage closure (LAAC) are increasingly performed as individual procedures. However, there are several studies which investigated a combined concomitant approach of perfoming a cryoballoon or radiofrequency based PVI and an interventional LAAC in one procedure and safety and efficacy has been shown.^1,2,3,4 The recently published OPTION trial showed that among patients who underwent thermal based PVI and sequential or concomitant LAAC was associated with a lower risk of non–procedure-related major or clinically relevant nonmajor bleeding than OAC and was noninferior to OAC with respect to a composite of death from any cause, stroke, or systemic embolism at 36 months.⁵ However only thermal based PVI has been utilized and only 40.8% of patients have been treated concomitantly.⁵

The novel ablation modality pulsed field ablation (PFA) has significantly reduced procedure duration and potentially increased safety due a specific ablation of cardiac tissue with sparing smooth muscle cells and nervous cells.⁶ With currently >100.000 treated patients most experience is currently available for the FARAPULSE PFA system (Boston Scientific). The MANIFEST-PF and MANIFEST 17K registries showed an excellent safety and efficacy profile of this novel ablation technology.^6,7 In patients with non-valvular AF, at high stroke risk, and who are ineligible for long-term oral anticoagulation LAAC could be an alternative to anticoagulation and safety and efficacy has been shown in several studies and registries.⁸ While PVI and LAAC are both conducted in the left atrium and share the same access route, a combined concomitant approach might be beneficial for patients but is not conventionally practiced. Due to significantly shorter procedures times and high safety profile PFA based catheter ablation may be advantageous for the combined approach of PVI and LAAC.

We aim to perform a retrospective, international, multicenter focusing on patients with concomitant Farapulse PFA based PVI and LAAC (WATCHMAN Flx, Boston Scientific). To evaluate safety, efficacy and efficiency in a multicenter study the CONOCNUT study was conducted. Two months after successful PVI and LAAC the OAC therapy could be terminated which might be beneficial for the patients especially for those with a higher bleeding risk. Further potential benefits are the reduction of periprocedural complications. Furthermore, economic factors could be beneficial due to only one concomitant procedure with one hospital stay instead of two procedures with two hospital stays.

• Age ≥ 18 years
• Willing to participate
• Atrial fibrillation and indication for PVI
• Indication for OAC therapy (CHA₂DS₂VA score >/=2)
• Indication for LAA closure

• Contraindications for PVI and / or LAA closure
• Pregnancy
• Previous catheter ablation for AF

Primary endpoints

• Safety (major complications, SAE)
• Efficacy (Success of PVI and LAA closure)

Secondary endpoints

• Periprocedural data
• Periprocedural minor complications (AE)
• Arrhythmia follow-up (Holter ECG after 3, 6, 12 months)
• LAA closure device follow-up (Gaps, Thrombus, Leakage analysed by TEE)
• Clinical follow-up (bleeding, stroke, TIA, death).

Studiendesign

retrospektives Register

Primäre Endpunkte

Durchführbarkeit, Sicherheit, Effektivität

Angestrebte Patientenzahl (bereits eingeschlossen)

70

Dauer Follow Up

12 Monate nach der Prozedur

Status

aktiv

Ethikvotum

Lokal vorliegend

Antizipierter Studienzeitraum

Januar 2021 – Dezember 2024

Geplante Anzahl teilnehmender Zentren

20

Davon bereits aktiv

10

Funding für teilnehmende Zentren

Nein

1.  Piccini et al. Left atrial appendage occlusion with the WATCHMAN FLX and concomitant catheter ablation procedures. Heart Rhythm Society Meeting 2023, May 19, 2023; New Orleans, LA
2. Phillips KP et al.  Combining Watchman left atrial appendage closure and catheter ablation for atrial fibrillation: multicentre registry results of feasibility and safety during implant and 30 days follow-up. Europace 2018;20:949–55.
3. Fassini  G,  et al.  Cryoballoon pulmonary vein ablation and left atrial appendage closure combined procedure: a long-term follow-up analysis. Heart Rhythm 2019;16:1320–6.
4. Phillips  KP, Romanov  A, Artemenko  S, Folkeringa  RJ, Szili-Torok  T, Senatore  G  et al.  Combining left atrial appendage closure and catheter ablation for atrial fibrillation: 2-year outcomes from a multinational registry. Europace 2020;22:225–31
5. Wazni et al. OPTION study, NEJM, 11/2024
6. Wintgens et al. Combined atrial fibrillation ablation and left atrial appendage closure: long-term follow-up from a large multi-centre registry. Europace(2018)20,1783–1789
7. Reddy VY, et al.  Pulsed field or conventional thermal ablation for paroxysmal atrial fibrillation. N Engl J Med 2024
8. Ekanem E et al. Safety of pulsed field ablation in more than 17,000 patients with atrial fibrillation in the MANIFEST-17K study , Nat Med 2024.
9. Potpara T, et al.  Practical guide on left atrial appendage closure for the non-implanting physician: an international consensus paper. Europace 2024;26:euae035.