CLEAN-TAVI Results Published for Claret Medical's Cerebral Protection System

August 15, 2016—Findings from the CLEAN-TAVI (Claret Embolic Protection and Transcatheter Aortic Valve Implantation) randomized controlled trial were published by Stephan Haussig, MD, in the Journal of the American Medical Association (JAMA; 2016;316:592–601).  

The results were first presented in September 2014 by Lead Investigator Axel Linke, MD, at the 26th annual Transcatheter Cardiovascular Therapeutics scientific symposium in Washington, DC. At that time, Dr. Linke reported that the study found that using Claret Medical’s cerebral protection system (CPS) with the CoreValve transcatheter aortic valve replacement (TAVR) system (Medtronic plc) can significantly reduce the number and volume of cerebral lesions in high-risk patients with severe aortic stenosis. Dr. Linke is a Professor at the University of Leipzig Heart Center in Germany, which cosponsored the trial with Claret Medical and Medtronic.

Claret Medical’s Sentinel CPS has received CE Mark approval and is commercially available in Europe. It is limited to investigational use in the United States. The filter-based device captures and removes embolic debris released during TAVR procedures. 

As summarized in JAMA, the investigator-initiated, single-center, blinded, randomized clinical trial studied higher-risk patients with severe aortic stenosis undergoing TAVR at the University of Leipzig Heart Center. The investigation sought to determine the effect of the Claret CPS on the number and volume of cerebral lesions in patients undergoing TAVR.

The investigators performed brain MRIs at baseline, 2 days, and 7 days after TAVR. Between April 2013 and June 2014, patients were randomly assigned to undergo TAVR with a cerebral protection device (filter group) or without a cerebral protection device (control group). The last 1-month follow-up occurred in July 2014.

The primary endpoint was the numerical difference in new positive postprocedure diffusion-weighted MRI brain lesions at 2 days after TAVR in potentially protected territories. The first hierarchical secondary outcome was the difference in volume of new lesions after TAVR in potentially protected territories.

The investigators reported in JAMA that among the 100 enrolled patients, mean (standard deviation [SD]) age was 80 (5.1) years in the filter group (n = 50) and 79.1 (4.1) years in the control group (n = 50), and the mean (SD) procedural risk scores (logistic EuroSCORE) were 16.4% (10%) in the filter group and 14.5% (8.7%) in the control group. 

For the primary endpoint, the number of new lesions was lower in the filter group, 4 (interquartile range [IQR], 3–7.25) versus 10 (IQR, 6.75–17) in the control group (difference, 5 [IQR, 2–8]; P < .001). 

For the first hierarchical secondary endpoint, new lesion volume after TAVR was lower in the filter group (242 mm³ [confidence interval (CI), 159–353]) versus in the control group (527 mm³ [95% CI, 364–830]) (difference, 234 mm³ [95% CI, 91–406]; P = .001). 

In considering adverse events, one patient in the control group died before the 30-day visit. Life-threatening hemorrhages occurred in one patient in the filter group and one in the control group. Major vascular complications occurred in five patients in the filter group and six patients in the control group. One patient in the filter group and five in the control group had acute kidney injury, and three patients in the filter group had a thoracotomy.

The CLEAN-TAVI investigators concluded that among patients with severe aortic stenosis undergoing TAVR, the use of a cerebral protection device reduced the frequency of ischemic cerebral lesions in potentially protected regions. Larger studies are needed to assess the effect of cerebral protection device use on neurological and cognitive function after TAVR and to devise methods that will provide more complete coverage of the brain to prevent new lesions, advised the investigators in JAMA.