Clinical Trial Details
— Status: Completed
Administrative data
| NCT number |
NCT02268539 |
| Other study ID # |
B703 |
| Secondary ID |
|
| Status |
Completed |
| Phase |
N/A
|
| First received |
|
| Last updated |
|
| Start date |
February 1, 2014 |
| Est. completion date |
December 31, 2017 |
Study information
| Verified date |
December 2020 |
| Source |
Mid and South Essex NHS Foundation Trust |
| Contact |
n/a |
| Is FDA regulated |
No |
| Health authority |
|
| Study type |
Interventional
|
Clinical Trial Summary
This is a pilot study designed to investigate the effectiveness of the nMARQ Pulmonary Vein
Isolation system in the treatment of Paroxysmal Atrial Fibrillation (AF) at different
ablation settings.
AF is a common condition which causes a fast and erratic heartbeat. There are estimated to be
50,000 new cases diagnosed per year in the UK. The fast heart beat can cause symptoms such as
palpitations, lightheadedness, chest pains, shortness of breath and fatigue.
Catheter ablation is a technique used for the control of AF. In this procedure a catheter (a
long thin wire) is passed into the chambers of the heart via a large blood vessel in a leg.
The tip of the catheter can destroy tiny sections of heart tissue that may be the source or
trigger of the abnormal electrical impulses. One of the challenges of AF ablation is to
maximize success rates, as such there is currently rapid advances in technology to carry out
this procedure.
Different catheters exist which deliver this energy in different ways. This study uses one
such system to perform this procedure. It is called the nMARQ system for Pulmonary Vein
Isolation produced by Biosense Webster. Currently this system is used in practice in the UK
for patients with this medical condition.
What we seek to research is when ablating what is the optimum setting to perform ablation at.
There is currently no data to guide best clinical practice in this area.
Description:
This is a pilot study designed to investigate the use of the nMARQ Pulmonary Vein Isolation
system in the treatment of Paroxysmal Atrial Fibrillation (AF) at different ablation
settings.
At least one month prior to the ablation procedure, an Implanted Loop Recorder (ILR) (the
REVEAL XT) will be implanted into the patient for robust, continuous, long term monitoring of
the burden of arrhythmia following the case.
It has been decided to use continuous implanted rhythm monitors to allow for robust complete
data capture of arrhythmia recurrence and burden with little impact to the patient after
implantation. These are increasingly being used in the follow up of patients undergoing AF
ablation. They give a continuous data feed showing the presence and quantity of abnormal
rhythm seen after ablation. Their use has been approved in the follow up of AF ablation
procedures within recent consensus guidelines formulated by the American College of
Cardiology, the American Heart Association, the European Cardiac Arrhythmia Society, the
European Heart Rhythm Association, the Society of Thoracic Surgeons, and the Heart Rhythm
Society. There are several papers showing the validation of data collected by the REVEAL XT
ILR and the benefit of continuous monitoring versus conventional methods of intermittent
ambulatory ECGs.
The settings chosen for ablation are guided both by preclinical data collected by Biosense
Webster and also the settings being used clinically worldwide when utilising this system. It
has been decided to have a two by two study design varying the wattages 20W and 25W and also
varying the time periods per lesion 20 seconds and 40 seconds.
We feel that this project can be carried out as a pilot study to potentially inform further
research. There is very little clinical data published on how best to use of this device. At
present it is left to individual clinicians to form their own "best practise" when choosing
ablation settings. We seek to formalise the potential ablation variables into a structured
format that will allow for comparisons to be drawn at the end of the study and to form the
basis of future research.
Following the current pathway, patients are admitted 24 hours prior to their treatment for
further, standard, tests (including an Echo TOE and pregnancy test); at this point patients
will be randomised to one of the arms of the trial, at an equal 1:1:1:1 ratio. As the study
is ' unblinded ' and the procedure constitute standard care in the NHS , it would be at this
point that the participant and Consultant have time to discuss the impact of the setting that
the participant has been randomised to, thereby reducing any anxiety on the day of the
procedure.
The following day, the procedure would be carried according to standard treatment and
following national guidelines using one of the ablation presets as per randomisation.
Within the UK it is standard practice to have a follow-up visit at 6 weeks, 3 months, 6
months and 12 months. At each visit, in addition to the standard tests, the patient and
Consultant would complete questionnaires.
After one year the patient will attend for removal of the ILR unless it is deemed to have
clinical use for them.
Recruitment and Consent Our target population will be patients who would routinely be having
catheter ablation of their AF. They will have the kind of AF that comes and goes and will be
troubled symptomatically by it. This research study has been constructed around a patients'
normal care pathway, minimising the need for additional visits or activities.
Risks, burdens and benefits Potential risks and burden of participation in the study centre
on the use of the ILR for rhythm recording both before and after the ablation procedure. This
device is small and implantation is a minor day case procedure done under local anaesthetic.
The risk of implantation is very small. Its use in the follow up after AF ablation is
endorsed by international clinical guidelines and backed up by scientific data. The use of
the ILR after AF ablation is becoming more commonplace and if anything is constrained by
financial issues in the NHS rather than any ethical considerations about the risks or burdens
of implantation.
Potential benefit to the participant also involves the ILR. By having a continuous monitor of
heart rhythm after ablation the consultant has information that can guide clinical management
decision making after the ablation occurs. In clinical practise, without the ILR in place,
the patient would otherwise have to undergo a number of ambulatory ECG monitors periodically
throughout the follow up period
