Filter-based cerebral embolic protection with transcatheter aortic valve implantation: the randomised MISTRAL-C trial

Selected in EuroIntervention by S. Brugaletta



Van Mieghem NM, van Gils L, Ahmad H, van Kesteren F, van der Werf HW, Brueren G, Storm M, Lenzen M, Daemen J, van den Heuvel AF, Tonino P, Baan J, Koudstaal PJ, Schipper ME, van der Lugt A, de Jaegere PP


EuroIntervention. 2016 Jul 20;12(4):499-507


July 2016


Read the abstract

My Comment

What is known 

Transcatheter aortic valve implantation (TAVI) is less invasive and results in faster recovery and improvement in quality of life as compared to surgical aortic valve replacement (SAVR). However, major stroke is still a vexing complication associated with aortic valve replacement, with recent studies suggesting similar stroke rates with SAVR and TAVI, varying between 2 and 10%. Approximately half of all strokes within 30 days after TAVI occur in the first 24 hours and are thus directly related to the procedure. TAVI inevitably releases debris from the aortic wall, the aortic annulus and even from cardiac structures, and catheter-related foreign body particles.

The SentinelTM Cerebral Protection System (CPS) (Claret Medical Inc., Santa Rosa, CA, USA) provides filter protection to the brachiocephalic trunk and the left common carotid artery. The safety and efficacy of the device were demonstrated and the device obtained CE mark in January 2014. The aim of this study was to determine whether use of the Sentinel CPS during TAVI can decrease the incidence of new brain lesions as assessed by DW-MRI, and can prevent neurocognitive decline.

Major findings 

  • From January 2013 to July 2015, 65 patients were randomised 1:1 to transfemoral TAVI with or without the Sentinel CPS.
  • Patients underwent DW-MRI and extensive neurological examination, including neurocognitive testing one day before and five to seven days after TAVI.
  • Follow-up DW-MRI and neurocognitive testing was completed in 57% and 80%, respectively.
  • New brain lesions were found in 78% of patients with follow-up MRI. Patients with the Sentinel CPS had numerically fewer new lesions and a smaller total lesion volume (95 mm3 [IQR 10-257] vs. 197 mm3 [95-525]).
  • Neurocognitive deterioration was present in 4% of patients with Sentinel CPS vs. 27% of patients without (p=0.017).
  • The filters captured debris in all patients with Sentinel CPS protection

My comment

In TAVI procedure, the rate of ischemic stroke is somehow underestimated. However, it is a real and actual problem, which is of importance especially looking forward to treat an intermediate risk population with TAVI. For this reason, the use of embolic protection devices should be highlighted and should be known to the interventional cardiologists who perform TAVI. The present article, despite limitations due to its small statistical power, shows the efficacy and safety of a new embolic protection device. It is still to be investigated which is the most useful, safe and easiest embolic protection device to use in TAVI procedure.

Do you use such devices in your TAVI practice?


  • subbarao myla 07 Aug 2016

    Not clear how the conclusions can be justified if only 57% of Claret group completed MRI exam and only 80% completed Neurocognitive testing? With such small numbers even 20% of patients not getting neuro cognitive testing could alter the results leave alone 43% without MRI exam? Am I missing something here?

  • Salvatore Brugaletta 11 Aug 2016

    Dear Subbarao, many thanks for your comment. I apologize if there was no clear. The percentages of 57 and 80 refer to the overall population and not only to the Claret group. As no mention is done in the paper, I suppose that there was no difference between the two groups in undergoing MRI and neurocognitive testing. So if there was a problem of underestimation it was in both groups. Anyway I agree with you that the study had a big drop-out of patients in performing these tests. A sensitivity analysis, considering all the missing patients with lesions on MRI or altered neurocognitive tests would have been of help, but unfortunately it was not performed by the authors