Hybrid ablation of atrial fibrillation in heart failure
| ISRCTN | ISRCTN31213485 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN31213485 |
| ClinicalTrials.gov (NCT) | NCT05411614 |
| Clinical Trials Information System (CTIS) | Nil known |
| Integrated Research Application System (IRAS) | 291145 |
| Protocol serial number | Nil known |
| Sponsor | City St George's, University of London |
| Funder | AtriCure |
- Submission date
- 03/11/2025
- Registration date
- 05/11/2025
- Last edited
- 05/11/2025
- Recruitment status
- Recruiting
- Overall study status
- Ongoing
- Condition category
- Circulatory System
Plain English summary of protocol
Background and study aims
Atrial fibrillation is associated with significant symptoms, impairment of quality of life and morbidity, particularly when it co-exists with impaired left ventricular function (heart failure). At present, patients with AF who are candidates for AF ablation can be offered either Hybrid AF ablation or catheter ablation as part of their usual care. The objective of this study is to evaluate the safety and efficacy of convergent hybrid ablation when compared to standard catheter ablation. As part of the trial, patients will be randomly allocated to one treatment, and data will be collected to ascertain whether one procedure is superior.
Who can participate?
Adult patients with persistent AF who would be routinely referred for AF ablation as part of their usual care.
What does the study involve?
Participants will undergo AF ablation either with Convergent Hybrid AF ablation (two-stage, epicardial and endocardial ablation) or with standard catheter ablation (single-stage, groin-only). The interventions that are being performed within this trial are the same as the routinely offered procedures to patients in clinical care. Following the procedure, data will be collected for up to 24 months to ascertain the response to treatment.
What are the possible benefits and risks of participating?
The treatments are the same as those received as part of usual care. Patients will benefit from contact with a dedicated research team and follow-up.
Where is the study run from?
St George's University Hospital, UK.
When is the study starting and how long is it expected to run for?
July 2021 to May 2027
Who is funding the study?
Investigator initiated and funded. Supported by Atricure
Who is the main contact?
Dr Riyaz A Kaba, rkaba@sgul.ac.uk
Dr Omar Ahmed, m2109536@sgul.ac.uk
Contact information
Scientific, Principal investigator
St George's Hospital NHS Trust
London
SW17 0QT
United Kingdom
| Phone | +44 (0)20 8725 4571 |
|---|---|
| rkaba@sgul.ac.uk |
Scientific, Principal investigator
St George's Hospital NHS Trust
London
SW17 0QT
United Kingdom
 ORCID ID |
0000-0002-4416-8986 |
|---|---|
| Phone | +44 (0)20 8725 4571 |
| m2109536@sgul.ac.uk |
Public
St George's University Hospital NHS Trust
London
SW17 0QT
United Kingdom
| Phone | +44 (0)20 8725 4571 |
|---|---|
| researchgovernance@sgul.ac.uk |
Study information
| Primary study design | Interventional |
|---|---|
| Study design | Prospective randomized controlled trial |
| Secondary study design | Randomised controlled trial |
| Study type | Participant information sheet |
| Scientific title | A randomised controlled trial comparing hybrid convergent ablation to standard catheter ablation in patients with non-paroxysmal atrial fibrillation and heart failure |
| Study acronym | HALT AF |
| Study objectives | The objective of this randomised study is to evaluate the safety and efficacy of Convergent hybrid ablation when compared to standard catheter ablation in patients with non-paroxysmal AF and impaired left ventricular systolic function. The hypothesis being tested is: Convergent Hybrid Ablation is superior to standard catheter ablation for the rhythm control of persistent AF in patients with reduced left ventricular ejection fraction |
| Ethics approval(s) |
Approved 07/07/2021, South West – Cornwall and Plymouth Research Ethics Committee (Whitefriars, Lewins Mead, Bristol, BS1 2NT, United Kingdom; +44 (0)2071048033; cornwallandplymouth.rec@hra.nhs.uk), ref: 21/SW/0082 |
| Health condition(s) or problem(s) studied | Persistent atrial fibrillation, heart failure |
| Intervention | Randomisation will utilise a centralised, anonymised, secure web-based application termed REDCap (Research Electronic Data Capture) that allows for longitudinal data collection with audit trails to ensure data integrity. It will be accessed via a secure server stored within St George's University, London, UK. Once enrolled, a patient identification number (PIN) will be generated by registering the patient for an eCRF (electronic case report file). Authorised and trained staff will be allocated a username and password. Once informed consent and eligibility are confirmed, a staff member can enter the subject's details, and the software will automatically randomly assign the subject to a trial arm. Trials arms: 1. Convergent Hybrid Ablation +/- Left Atrial Appendage Exclusion. Consisting of two stages: Stage 1 - Minimally-Invasive Surgical Epicardial Ablation Procedure +/- concomitant left atrial appendage (LAA) exclusion. Stage 2 - Endocardial Catheter Ablation 2. Standard Endocardial Catheter Ablation |
| Intervention type | Procedure/Surgery |
| Primary outcome measure(s) |
Freedom from persistent atrial arrhythmia as recorded on prolonged Holter electrocardiogram (ECG) monitoring after a single procedure (either the completed hybrid ablation or catheter ablation), off Class I or III medications up to 12 months post-ablation |
| Key secondary outcome measure(s) |
1. Safety endpoint of severe and non-severe complications, as defined in the protocol, measured up to 30 days post procedure (early), and up to 12 months (late) |
| Completion date | 01/05/2027 |
Eligibility
| Participant type(s) | Patient |
|---|---|
| Age group | Adult |
| Lower age limit | 18 Years |
| Sex | All |
| Target sample size at registration | 120 |
| Key inclusion criteria | 1. Age ≥ 18 years 2. Persistent or Long-standing Persistent AF 3. Dilated left atrium 4. Suitable for either procedure 5. LVEF < 50% |
| Key exclusion criteria | 1. Not yet optimised from a medical or lifestyle perspective for AF or heart failure 2. Unable to provide written consent 3. Previous open-heart surgery 4. Active infection, oesophageal ulcer stricture or oesophageal varices 5. Prior catheter ablation of atrial fibrillation (prior ablation for atrial flutter / supraventricular tachycardia or ventricular arrhythmia acceptable) 6. Contraindication to anticoagulation, or active thrombus in the left atrium despite therapeutic anticoagulation 7. Severe valvular heart disease 8. Unstable coronary artery disease 9. Uncontrolled ventricular arrhythmia 10. Heart attack or stroke within the last 90 days 11. Pregnant, breastfeeding, or women of childbearing age who plan to get pregnant within six months 12. Severe concomitant condition or presence of an implanted device that would preclude the patient from undergoing trial procedures |
| Date of first enrolment | 01/05/2022 |
| Date of final enrolment | 01/05/2026 |
Locations
Countries of recruitment
- United Kingdom
- England
Study participating centres
London
London
SW17 0QT
United Kingdom
Guildford Road
Chertsey
KT16 0PZ
United Kingdom
Dorking Road
Epsom
KT18 7EG
United Kingdom
Kingston upon Thames
KT2 7QB
United Kingdom
Worcester Park
London
SM3 9DW
United Kingdom
London
SW5 0TU
United Kingdom
Results and Publications
| Individual participant data (IPD) Intention to share | Yes |
|---|---|
| IPD sharing plan summary | Available on request, Published as a supplement to the results publication |
| IPD sharing plan | The datasets generated and/or analysed during the current study will be published (where feasible) as a supplement to the results publication or will be made available upon reasonable request to the corresponding author (Dr Riyaz A Kaba, rkaba@sgul.ac.uk ) or trial sponsor |
Study outputs
| Output type | Details | Date created | Date added | Peer reviewed? | Patient-facing? |
|---|---|---|---|---|---|
| Participant information sheet | Participant information sheet | 11/11/2025 | 11/11/2025 | No | Yes |
Editorial Notes
04/11/2025: Study's existence confirmed by Health Research Authority (HRA) (UK).
