Clinical trial NCT05146037: INTERvention With Cerebral Embolic Protection in Transcatheter Aortic Valve Implantation (INTERCEPTavi)
Official title: INTERvention With Cerebral Embolic Protection in Transcatheter Aortic Valve Implantation (INTERCEPTavi): 'Carbon-Dioxide Flushing Versus Saline Flushing of Transcatheter Aortic Valves: A Single-centre Randomised Controlled Trial'
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Stroke
Aortic Valve Stenosis
Silent Cerebral Infarct
Vascular Brain Injury
Keywords: Stroke
Aortic Valve Stenosis
Silent Cerebral Infarct
Vascular Brain Injury
TAVI
Transcatheter aortic valve implantation
Transcranial doppler
Magnetic resonance imaging
CO2
Carbon dioxide
Lead sponsor: Imperial College London
Sponsor class: OTHER
Collaborators: name: Imperial College Healthcare NHS Trust
First posted: 2021-12-06
Enrollment: 120
Sex: ALL
Minimum age (years): 18
Maximum age (years): 100
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: Patients will be randomised to CO2 and Saline flushing versus saline flushing only.
Primary purpose: PREVENTION

Brief summary: The study aims to evaluate the processes of a pilot single-centre randomised controlled trial (RCT) of carbon-dioxide flushing of transcatheter aortic valves (TAVI-CO2) versus standard saline flushing of valves (TAVI-S) and assess potential neuroprotection through a number of neurological endpoints for planning of a full-sized RCT

Detailed description: Aortic stenosis (AS) is one of the most common valve diseases and is increasing worldwide due to an ageing population. Transcatheter Aortic Valve Replacement (TAVI) is a keyhole procedure that can be done through the groin to replace the narrowed aortic valve with a new valve, avoiding the need for cardiac surgery.Improved device design and greater operator experience has improved TAVI outcomes. It has become the standard treatment option in patients who are at high risk for cardiac surgery and is now being used increasingly in lower risk patients.

Cerebrovascular accidents in TAVI patients remain a significant risk with a reported 3 - 5 % risk. Furthermore, these patients have neurovascular injury that is not clinically identifiable. Covert brain injury has been identified to occur in many surgical and cardiovascular catheter-based interventions such as TAVI and can cause vascular brain injury (VBI).

TAVI valves are manufactured in room air conditions and retain air. Studies in TEVAR (Thoracic Endovascular Aortic Repair) stent grafts have shown release of air when they are deployed in the aorta. In vitro testing of TAVI valves has shown release of air when they are deployed.

Carbon-dioxide (CO2) is 1.5 times denser than air and can displace it. It is 25 times more soluble in blood than air and does not lead to bubble formation. Hence CO2 bubble are unlikely to result in significant damage. CO2 has been used in cardiac surgery with beneficial effects. It has shown to reduce peri-procedural cerebral air embolisation and post operative cognitive dysfunction.

This study aims to look at the neuroprotective benefits of flushing TAVI valves with CO2 and saline versus saline only by reducing air embolisation.

Patients undergoing TAVI will be approached to participate in this study. After consent is obtained, patients will undergo baseline MRI, neurological and neurocognitive testing pre-TAVI. Patient will be randomised to saline only or CO2 and saline flushing of their valves. During their TAVI procedure, they will have transcranial doppler (TCD) monitoring of their middle cerebral artery (MCA) bilaterally to record cerebral embolisation. Patients will also have biomarker testing pre-TAVI, post-TAVI and 24 hours following TAVI. They will have DW-MRI brain between day 1-7 following their TAVI to look for vascular brain injury. Thus MRI will be repeated at 6-months following their TAVI. Patients will also have neurological and neurocognitive testing during their inpatient admission, at 6-weeks and 6-months outpatients.

Eligibility criteria: Inclusion Criteria:

* All patients between the ages of 18 and 100 years undergoing transcatheter aortic valve implantation (TAVI) for aortic stenosis under local anaesthetic.

Exclusion Criteria:

* Patients that lack capacity to provide informed consent
* Patients that have had a stroke within 12 months
* Patients aged less than 18 years of age
* Patients that are pregnant

Primary outcomes:
measure: Number of participants suitable for recruitment for larger RCT
timeFrame: Duration of study, approximately 15 months
Secondary outcomes:
measure: Incidence of Vascular Brain Injury (VBI) on Diffusion Weighted-Magnetic Resonance Imaging (DW-MRI)
timeFrame: Post TAVI 1-7 days and 6-months post TAVI
Other outcomes:
measure: Detection of periprocedural cerebral solid and gaseous emboli
timeFrame: During TAVI procedure
measure: Neurological deficit
timeFrame: 6 Months
measure: Inflammatory biomarker assessing brain injury
timeFrame: 24 hours post TAVI
measure: Neurocognitive decline
timeFrame: 6 Months
Locations:
city: London
country: United Kingdom
facility: Imperial College London
Study officials:
affiliation: Imperial College London
name: Ghada Mikhail
role: PRINCIPAL_INVESTIGATOR
References:
citation: Inci K, Koutouzi G, Chernoray V, Jeppsson A, Nilsson H, Falkenberg M. Air bubbles are released by thoracic endograft deployment: An in vitro experimental study. SAGE Open Med. 2016 Dec 7;4:2050312116682130. doi: 10.1177/2050312116682130. eCollection 2016.
citation: Rohlffs F, Tsilimparis N, Saleptsis V, Diener H, Debus ES, Kolbel T. Air Embolism During TEVAR: Carbon Dioxide Flushing Decreases the Amount of Gas Released from Thoracic Stent-Grafts During Deployment. J Endovasc Ther. 2017 Feb;24(1):84-88. doi: 10.1177/1526602816675621. Epub 2016 Oct 26.
citation: Martens S, Neumann K, Sodemann C, Deschka H, Wimmer-Greinecker G, Moritz A. Carbon dioxide field flooding reduces neurologic impairment after open heart surgery. Ann Thorac Surg. 2008 Feb;85(2):543-7. doi: 10.1016/j.athoracsur.2007.08.047.
citation: Bismuth J, Garami Z, Anaya-Ayala JE, Naoum JJ, El Sayed HF, Peden EK, Lumsden AB, Davies MG. Transcranial Doppler findings during thoracic endovascular aortic repair. J Vasc Surg. 2011 Aug;54(2):364-9. doi: 10.1016/j.jvs.2010.12.063. Epub 2011 Mar 3.
citation: Perera AH, Rudarakanchana N, Monzon L, Bicknell CD, Modarai B, Kirmi O, Athanasiou T, Hamady M, Gibbs RG. Cerebral embolization, silent cerebral infarction and neurocognitive decline after thoracic endovascular aortic repair. Br J Surg. 2018 Mar;105(4):366-378. doi: 10.1002/bjs.10718. Epub 2018 Feb 12.