HD grid vs circular mapping catheter for assessment of pulmonary vein reconnection
| ISRCTN | ISRCTN30513341 |
|---|---|
| DOI | https://doi.org/10.1186/ISRCTN30513341 |
| IRAS number | 273987 |
| Secondary identifying numbers | CPMS 48319 |
- Submission date
- 01/04/2021
- Registration date
- 08/04/2021
- Last edited
- 02/07/2024
- Recruitment status
- No longer recruiting
- Overall study status
- Completed
- Condition category
- Circulatory System
Plain English Summary
Background and study aims
Atrial fibrillation (AF) is the most common heart rhythm disturbance where the heart does not beat in a regular rhythm.
Normal heart rhythm depends on regular electrical activity of your heart’s natural pacemaker cells – the sinus node. The sinus node is in the right upper chamber of the heart and usually ‘fires’ at about 60-100 beats per minute but it can be faster (during exercise, for example). The electrical impulse spreads through the heart to create a coordinated contraction between the upper chambers and lower chambers. In AF, the normal rhythm is lost due to abnormal electrical activity from an area around the pulmonary veins (they bring blood from the lungs to the heart). This results in a chaotic rhythm (fibrillation) in the atria, which stops them contracting effectively.
One available treatment, ablation, works by making small burn marks, to isolate those areas that are causing extra beats in the heart, or the pulmonary veins leading to the heart, and stopping them from sending these signals to the rest of the heart. However, there is a 40-50% chance of AF reoccurrence after a single ablation due to electrical reconnection of at least one vein.
The reason we are performing this multicentre study is to establish whether a new catheter (HD Grid), that has already been tested and approved for safety and efficiency and which can map the heart in higher detail than less advanced catheters currently used in standard practice (Circular Mapping Catheters), results in improved outcomes in 130 patients.
Who can participate?
People can participate who:
- Have documented recurrence of AF
- Have one previous AF ablation
- Are suitable for clinically indicated catheter ablation
- Are aged over18 years
People can not participate who:
- Are pregnant or planning pregnancy
- Are currently enrolled in another investigational trial
- Show pulmonary vein isolation on mapping at the baseline visit
What does the study involve?
Much of the study will involve the same procedures as those needed for a standard ablation procedure, such as assessing fitness to undergo an ablation procedure. In addition to the standard procedure, additional mapping of the atrium (heart chamber) with a second catheter will occur to create a second map of the atrium. In the procedure the first mapping catheter will be inserted and a map made and then withdrawn. Then through the same channel the second mapping catheter will be inserted and a map made. The additional mapping with a second catheter takes approximately 20 minutes.
Once both maps have been created, one of the two maps will be chosen at random in order to identify where the locations of electrical reconnection to the pulmonary veins are. Ablation will be performed in order to remove the electrical reconnection based on the map. After this part of the procedure, the operator can assess if more ablation is required based on both the maps created to decide this.
There is no follow-up required apart from what is standard in routine practice.
What are the possible benefits and risks of participating?
The operator having access to both maps to visualise the area of the heart may mean that there is less chance of AF recurrence.
We do not believe there will be any significant additional or increased risk from taking part in the study. As the mapping and ablation procedure involves the use of ionising radiation the additional mapping may add up to approximately 25% more radiation than the standard AF ablation procedure.
Where is the study run from?
Royal Sussex County Hospitals (UK)
When is the study starting and how long is it expected to run for?
February 2021 to February 2023
Who is funding the study?
Abbot Laboratories (UK)
Who is the main contact?
Dr John Silberbauer, john.silberbauer@nhs.net
Contact information
Scientific
Royal Sussex County Hospitals
Eastern Road
Brighton
BN2 5BE
United Kingdom
| Phone | +44 (0) 1273 696955 |
|---|---|
| john.silberbauer@nhs.net |
Study information
| Study design | Interventional randomized controlled trial |
|---|---|
| Primary study design | Interventional |
| Secondary study design | Randomised controlled trial |
| Study setting(s) | Hospital |
| Study type | Treatment |
| Participant information sheet | See study outputs table |
| Scientific title | Comparative study of Advisor HD grid versus circular mapping catheters in assessment of pulmonary vein isolation following previous ablation for atrial fibrillation |
| Study hypothesis | The HD Grid catheter will reduce the RF time to isolation by at least 20% as compared with the standard Circular mapping catheter |
| Ethics approval(s) | Approved 15/03/2021, East of England - Cambridge Central Research Ethics Committee (The Old Chapel, Royal Standard Place, Nottingham, NG1 6FS, UK; +44 (0)2071048384; cambridgecentral.rec@hra.nhs.uk), ref: 21/EE/0033 |
| Condition | Atrial fibrillation |
| Intervention | The procedure will be performed by a Consultant Cardiologist or Specialist Registrar with experience of catheter ablation for AF. All patients recruited will have a clinical indication for AF ablation and will have undergone a previous ablation procedure for AF (using either radiofrequency or freezing for the first procedure). All procedures will be conducted under general anaesthesia or local anaesthetic with sedation. STANDARD CLINICAL PROCEDURE: Following general anaesthesia/local anaesthesia with sedation, an ultrasound probe is inserted down the oesophagus (at the discretion of the operator and in accordance with local guidelines). Small tubes will be placed in the femoral veins to allow specialised catheters to be placed inside the chambers of the heart. Access in to the left atrium, where the majority of AF ablation is undertaken, is carried out using a standard technique called a transseptal puncture. This involves a fine needle being used to create a small hole from the right atrium in to the left atrium to allow passage of catheters. At this point, a specially timed electric shock called a cardioversion will be performed to restore the heart to a normal rhythm. A map of the left atrium is created by using a specialised mapping catheter. Once a map has been created, location in which there are electrical reconnection of the pulmonary veins can be identified, and treated with a series of small burn marks to destroy the unwanted connections. RESEARCH PROTOCOL: The research protocol represents only a small modification of the standard clinical procedure. Ordinarily, a single electrical map of the left atrium will be made with a specialised mapping catheter. In research patients, two electrical maps of the left atrium will be created, using both a circular catheter, and an HD Grid catheter. Each of the two mapping catheters will be used, one after the other, to create an electro-anatomical map of the left atrium and pulmonary veins. This is done to identify any areas at the pulmonary veins that have electrically reconnected. The electrical activity on the map will be blinded to the operator. This can be done by changing some settings on the mapping system. One of the two maps created with the two catheters for comparison will be randomly selected. The operator will then be allowed to review the electrical information on the map in order to identify areas in which electrical activation has reconnected at the pulmonary veins in order to direct ablation therapy to re-isolate the pulmonary veins. This minor modification involves mapping with the standard circular catheter, with the addition of mapping to create a second map using the new catheter. It is expected that this will prolong the procedure by around 20 minutes. However, during clinical procedures, we take time to review maps and other information in order to ensure a high quality procedure has been undertaken. We also commonly create multiple maps during a single procedure. Use of two different electroanatomic mapping(s)(EAMs) may shorten procedures, as there would be a greater level of certainty that sufficient treatment has been delivered. It is common that operators use a variety of different techniques to conform that sufficient treatment has been undertaken, beyond the EAMs. These additional techniques can be avoided with the use of two EAMs. |
| Intervention type | Procedure/Surgery |
| Primary outcome measure | Radiofrequency energy time to isolate reconnected pulmonary veins (measured in seconds during the procedure) |
| Secondary outcome measures | 1. Mapping times for both catheters (HD Grid and Circular mapping catheter) (measured in seconds during the procedure using the Ensite electro-anatomical mapping system) 2. Ability to correctly identify the gaps in pulmonary veins (recorded during the procedure by analysis of electroanatomical maps by cardiac electrophysiologist) 3. Location of isolation of pulmonary vein (recorded during procedure using electroanatomical maps) 4. Duration of ablation procedure (recorded during the procedure) 5. Any procedural complication (pericardial effusion, bleeding >2 units, phrenic nerve palsy and other) (recorded during and after the procedure via routine clinical follow up within 30 days) |
| Overall study start date | 15/02/2021 |
| Overall study end date | 15/02/2023 |
Eligibility
| Participant type(s) | Patient |
|---|---|
| Age group | Adult |
| Lower age limit | 18 Years |
| Sex | Both |
| Target number of participants | Planned Sample Size: 130; UK Sample Size: 130 |
| Total final enrolment | 172 |
| Participant inclusion criteria | 1. Documented recurrence of AF 2. One previous AF ablation 3. Suitable for clinically indicated catheter ablation 4. Aged >18 years |
| Participant exclusion criteria | 1. Pregnancy or planning pregnancy 2. Current enrolment in another investigational trial 3. Pulmonary vein isolation on mapping at baseline |
| Recruitment start date | 01/05/2021 |
| Recruitment end date | 15/05/2023 |
Locations
Countries of recruitment
- England
- United Kingdom
Study participating centres
Eastern Road
Brighton
BN2 5BE
United Kingdom
729 the Ridge
St. Leonards-On-Sea
TN37 7PT
United Kingdom
Barrack Road
Exeter
EX2 5DW
United Kingdom
Marlborough Street
Bristol
BS1 3NU
United Kingdom
Castle Lane East
Bournemouth
BH7 7DW
United Kingdom
Basildon
SS16 5NL
United Kingdom
Crownhill
Plymouth
PL6 8DH
United Kingdom
Clifford Bridge Road
Coventry
CV2 2DX
United Kingdom
Clydebank
G81 4DY
United Kingdom
Beckett Street
Leeds
LS9 7TF
United Kingdom
Headley Way
Headington
Oxford
OX3 9DU
United Kingdom
Sponsor information
Hospital/treatment centre
Royal Sussex County Hospital
Eastern Road
Brighton
BN2 5BE
England
United Kingdom
| scott.harfield@nhs.net | |
| Website | http://www.bsuh.nhs.uk/ |
Funders
Funder type
Industry
Government organisation / For-profit companies (industry)
- Alternative name(s)
- Abbott, Abbott U.S., Abbott Alkaloidal Company
- Location
- United States of America
Results and Publications
| Intention to publish date | 31/08/2024 |
|---|---|
| Individual participant data (IPD) Intention to share | Yes |
| IPD sharing plan summary | Available on request |
| Publication and dissemination plan | Planned publication in a high-impact peer-reviewed journal. |
| IPD sharing plan | The fully anonymised datasets generated and analysed during the current study will be available upon request from Dr John Silberbauer (john.silberbauer@nhs.net) after 31/08/2024 to applicants on consideration of relevance to catheter ablation studies. |
Study outputs
| Output type | Details | Date created | Date added | Peer reviewed? | Patient-facing? |
|---|---|---|---|---|---|
| HRA research summary | 28/06/2023 | No | No | ||
| Basic results | 01/07/2024 | 01/07/2024 | No | No |
Additional files
Editorial Notes
02/07/2024: The intention to publish date was changed from 31/03/2024 to 31/08/2024. IPD sharing plan added.
01/07/2024: Basic results added.
18/09/2023: Total final enrolment added. The intention to publish date was changed from 01/06/2023 to 31/03/2024.
07/09/2023: IRAS number added.
31/01/2023: The following changes were made to the trial record:
1. The recruitment end date was changed from 01/12/2022 to 15/05/2023.
2. University Hospitals Coventry and Warwickshire NHS Trust, Golden Jubilee National Hospital, Leeds Teaching Hospitals NHS Trust, Oxford University Hospitals NHS Foundation Trust were added to the trial participating centres.
01/04/2021: Trial's existence confirmed by the National Institute for Health Research (NIHR) (UK).
