Results from the MISTRAL-C study indicate that use of the Sentinel cerebral protection system (Claret Medical) during transcatheter aortic valve implantation (TAVI) procedures is associated with definitive cognitive benefit. The data were presented at the 2015 Transcatheter Cardiovascular Therapeutics meeting (11–15 October, San Francisco, USA).
A press release reports that in MISTRAL-C, 65 patients—enrolled at four centres in the Netherlands—underwent TAVI (with both self-expanding and balloon-expandable valves) with or without the use of the Sentinel system. The study compared the median total new lesion volume as detected by DW-MRI at five days post-procedure to pre-procedural baseline cerebral scans. It also included a detailed neurological and cognitive assessment of patients five days post-procedure.
MISTRAL-C found that the system was associated with a 52% reduction in the median total new lesion volume at five days post-procedure as assessed using highly sensitive 3-Tesla brain MRI. None of the protected patients had National Institute of Health Stroke Scale (NIHSS) deterioration at five days post-procedure, while 5% of unprotected patients showed deterioration. Furthermore, the results of the study show that unprotected patients have a statistically significant (p=0.017) worsening in cognition when compared to Sentinel-protected patients at five days post-TAVI when assessed using the Mini Mental State Exam (MMSE).
Principal investigator Nicholas van Mieghem (Thoraxcenter, Erasmus Medical Center, Rotterdam, The Netherlands), who presented the data at TCT, says: “What is clear in MISTRAL-C is that patients not protected by the Sentinel cerebral protection system showed significant cognitive decline post-procedure when compared to those protected by the Sentinel cerebral protection system. Protected patients also showed a robust reduction in the number and volume of new cerebral lesions at five days.”
According to the press release, MISTRAL-C validates findings from the landmark CLEAN-TAVI study that showed the use of a Claret Medical cerebral protection system reduced the number and volume of brain lesions in TAVI patients. A post-hoc, 3D voxel-wise analysis of CLEAN-TAVI DW-MRI images was also presented at TCT. This illustrated that only 2% of the left posterior region of the brain remains fully unprotected when a Claret Medical cerebral protection system is used. The data were presented by Axel Linke (professor of Medicine, Department of Internal Medicine/Cardiology, University of Leipzig, Germany). He says: “Post hoc neuroimaging and neurological analysis is providing a more complete, and troubling, picture of the brain post-TAVI. Evidence is building that more sustained damage than we previously realized may be created when we don’t protect the brain from embolic debris. The use of cerebral protection, however, has now been shown to effectively shield the brain from potentially dangerous debris showers caused by the TAVI procedure.”
