Condition category
Circulatory System
Date applied
Date assigned
Last edited
Prospectively registered
Overall trial status
Recruitment status
Not yet recruiting

Plain English Summary

Background and study aims
Transcatheter Aortic Valve Implementation (TAVI) is a standard treatment for Aortic Stenosis (AS), a condition where blood flow out of the heart is restricted by narrowing of the aortic valve. In a TAVI procedure, the aortic valve is replaced by placing a new valve delivered to the heart through a tube (catheter) placed in an artery. One risk associated with TAVI is stroke. During the TAVI procedure, debris (made up of parts of the diseased aortic valve and the surrounding tissue) can be released into the bloodstream. Most strokes occurring at the time of TAVI are due to this debris blocking part of the blood supply in the brain. Devices have been developed that capture some of the debris released and stop this reaching the brain, these are called Cerebral Embolic Protection (CEP) devices.

The purpose of this study is to assess whether using a Cerebral Embolic Protection (CEP) device during Transcatheter Aortic Valve Replacement (TAVI) can reduce the chance of a patient having a stroke. The study will also determine whether it improves the quality of life for patients and how the use of CEP impacts the NHS in terms of cost and service use.

Who can participate?
Patients aged 18 years or above, diagnosed with aortic stenosis (including bioprosthetic valve dysfunction) and planned to undergo a transfemoral TAVI

What does the study involve?
In this study, patients who agree to take part (this means given written consent) receiving TAVI will be randomly assigned to receive CEP during TAVI or to the current standard of care without CEP. Potential participants will be approached prior to their TAVI procedure to discuss the trial.

What are the possible benefits and risks of participating?
We have no evidence that there are significant risks associated with using the CEP device. There are small risks associated with putting a device within an artery. These risks are less than 1% and include bleeding, infection or damage to the artery. The additional risks from the device are small.
The risks of a TAVI procedure itself include a 2-3% risk of stroke or death and a 10% risk of bleeding. You will be attended to and cared for by the standard care and clinical team throughout the procedure and your recovery.
If you take part in this study you will have a heart valve replacement procedure as part of your routine care. For some participants the procedure will be extended by about 10 minutes to place a cerebral embolic protection device. This time and procedure are extra to what you would have if you did not take part.
There is a small chance that patients in the TAVI with CEP arm will have to receive an small additional dose of X-ray contrast associated with the use of the CEP device. This could cause an injury to the kidney, however there are no reported cases of this happening to date.
The operation you are having uses ionising radiation to form images of your body. Ionising radiation can cause cell damage that may, after many years or decades, turn cancerous. Dose levels are monitored carefully during your intervention.
We are all at risk of developing cancer during our lifetime. The normal risk is that this will happen to about 50% of people at some point in their life. Having this procedure might increase the chances of this happening to you from 50% to 50.13% (this means that 13 in 1000 patients) might develop cancer. If you are in the group receiving CEP, the time for this radiation would be extended by 10 minutes.

Where is the study run from?
John Radcliffe Hospital (UK)

When is the study starting and how long is it expected to run for?
May 2020 to April 2026

Who is funding the study?
1. British Heart Foundation (UK)
2. Boston Scientific Corporation (USA)

Who is the main contact?
Alexander Perkins,

Trial website

Contact information



Primary contact

Mr Alexander Perkins


Contact details

Department of Medical Statistics
London School of Hygiene and Tropical Medicine
United Kingdom
+44 (0)20 7927 2723

Additional identifiers

EudraCT number

Nil known number

Nil known

Protocol/serial number

PID14772-SP001-AC001, IRAS 276396

Study information

Scientific title

British Heart Foundation Randomised Trial of Routine Cerebral Embolic Protection in Transcatheter Aortic Valve Implantation



Study hypothesis

Does the routine use of the Sentinel Cerebral Embolic Protection device during TAVI reduce stroke incidence?

Ethics approval

Approved 23/04/2020, Wales Research Ethics Committee 5, (Health and Care Research Wales Support and Delivery Centre, Castlebridge 4, 15-19 Cowbridge Road East, Cardiff, CF11 9AB, UK; +44 (0)7970 422139;

Study design

Prospective multicentre randomized controlled trial

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet

Not provided at time of registration


Aortic stenosis


The study is an RCT evaluating use of the cerebral embolic protection device (Sentinel, Boston Scientific) in participants with aortic valve stenosis planned for treatment by Transcatheter Aortic Valve Implantation (TAVI) using the transfemoral approach

Participants will be randomised 1:1 into a treatment cohort using the cerebral embolic protection device (Sentinel, Boston Scientific) or a control cohort with no cerebral protection system. Enrolled participants will be followed through 72 hours (or hospital discharge), whichever comes first, and assessed for the primary outcome.

Consented patients will be randomised at a 1:1 ratio to either the control or intervention arm at the time of the their TAVI procedure. This will be done using a secure online randomisation service.

The intervention group will have TAVI performed with CEP. The Claret Sentinel dual-filter device (Boston Scientific, MA, USA) is a single use, embolic protection catheter inserted into the right radial or brachial artery. This is the only device currently approved for clinical use in both Europe and the USA. The device employs two filters (nitinol frames with 140-micron pores polyurethane film), one delivered to the brachiocephalic artery (Proximal Filter), and one to the left common carotid artery (Distal Filter) before TAVI. Following the TAVI procedure the system is removed.

Intervention type



Phase IV

Drug names

Cerebral embolic protection device (Sentinel, Boston Scientific)

Primary outcome measure

The incidence of all stroke within 72 hours (or hospital dischage) of TAVI procedure, measured using patient records

Secondary outcome measures

Measured using patient records:
1. Combined incidence of all-cause mortality and stroke up to 12 months
2. Incidence of all-cause mortality up to 12 months
3. Cognitive outcomes up to 12 months
4. Vascular access site injury between 6-8 weeks post-TAVI
5. Acute kidney injury between 6-8 weeks post-TAVI
6. Cost-effectiveness analysis

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. Willing and able to give informed consent for participation in the trial.
2. Aged 18 years or above
3. Diagnosed with aortic stenosis (including bioprosthetic valve dysfunction)
4. Planned transfemoral TAVI

Participant type


Age group




Target number of participants


Participant exclusion criteria

1. Anatomically unsuitable for treatment with the cerebral embolic protection device in the opinion of the treating physician
2. Clinical contra-indications to the use of the CEP device in the opinion of the treating physician

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

John Radcliffe Hopsital
Oxford University Hospitals NHS Trust Headley Way Headington
United Kingdom

Sponsor information


University of Oxford

Sponsor details

Clinical Trials and Research Governance
Joint Research Office
1st floor
Boundary Brook House
Churchill Drive
United Kingdom
+44 (0)1865 616480

Sponsor type




Funder type


Funder name

British Heart Foundation

Alternative name(s)


Funding Body Type

private sector organisation

Funding Body Subtype

Trusts, charities, foundations (both publically funded and privately funded)


United Kingdom

Funder name

Boston Scientific Corporation

Alternative name(s)

Boston Scientific, Boston Scientific Corp., BSC

Funding Body Type

private sector organisation

Funding Body Subtype

For-profit companies (industry)


United States of America

Results and Publications

Publication and dissemination plan

Planned publication in major international scientific journals and present them at academic conferences. Lay results for patients will be available upon request through our trial website and via their local hospital.

IPD sharing statement:
The current data sharing plans for this study are unknown and will be available at a later date.

Intention to publish date


Participant level data

Not provided at time of registration

Basic results (scientific)

Publication list

Publication citations

Additional files

Editorial Notes

29/05/2020: Trial’s existence confirmed by NHS HRA.