Results of CLEAN-TAVI Support Use of Claret's Cerebral Protection System

September 13, 2014—Axel Linke, MD, presented results of the CLEAN-TAVI trial at the 26^th annual Transcatheter Cardiovascular Therapeutics (TCT) scientific symposium in Washington, DC. The CLEAN-TAVI (Claret Embolic Protection and Transcatheter Aortic Valve Implantation) study found that using a cerebral protection device during transcatheter aortic valve replacement (TAVR) can significantly reduce the number and volume of cerebral lesions in high-risk patients with severe aortic stenosis.

The study used Claret Medical Inc.’s cerebral protection system (CPS) with Medtronic Inc.’s CoreValve TAVR system. Claret’s CPS is a filter-based device that both captures and removes embolic debris released during TAVR procedures that could otherwise be a source of acute stroke, the company advised in its recent announcement of completion of enrollment in the study.

Dr. Linke, the study’s lead investigator, is a Professor at the University of Leipzig Heart Center in Germany. The University of Leipzig Heart Center cosponsored the CLEAN-TAVI trial with Claret Medical and Medtronic, Inc.

As summarized in the TCT announcement, CLEAN-TAVI is a prospective, randomized, double-blind, single-center study conducted at the University of Leipzig Heart Center. The primary endpoint was the number of lesions in the protected brain region as determined by diffusion-weighted magnetic resonance imaging (DW-MRI) subtraction at 2 days after TAVR. Secondary endpoints included the total lesion volume at 2 and 7 days after TAVR and lesion number at 7 days. This is the first trial to examine the impact of a cerebral protection device in preventing MRI-detected brain lesions during TAVR, noted TCT.

The CLEAN-TAVI investigators enrolled 100 patients with severe aortic stenosis who were at increased surgical risk. Patients were randomly assigned in a 1:1 ratio to TAVR with cerebral protection (device group) or TAVR alone (control group). Patients underwent MRIs of the brain before and at 2 and 7 days after TAVR.

After 2 days, the median number of lesions in the protected regions in the device group was significantly lower than the control group (4 vs 10, respectively; P = .009). At 7 days after TAVR, the median lesion number was also significantly lower in the device group compared to the control group (3 vs 7; P = .0023). In addition, the median total lesion volume in the protected area was significantly smaller in the device group compared to the control group at 2 days (246 mm³ vs 527 mm³, respectively; P = .0023) and at 7 days (101 mm³ vs 292 mm³; P = .002).

In the TCT announcement, Dr. Linke commented, “In patients with severe aortic stenosis who are at increased surgical risk, the use of a cerebral protection device during TAVR significantly reduced the number of cerebral lesions in the protected brain regions. Device use also reduced the volume of cerebral lesions as determined by DW-MRI.”

In its earlier announcement, Claret Medical noted that the MRI scans would be assessed blindly by an independent core lab overseen by Robert Zivadinov, MD, of the Buffalo Neuroimaging Analysis Center in Buffalo, New York. Additionally, Renu Virmani, MD, at CVPath Institute of Pathology in Gaithersburg, Maryland, will perform an evaluation of patients’ neurological and neurocognitive functions and will conduct a blinded histopathological review of the captured debris.

In a press release issued by Claret Medical at TCT 2014, Dr. Linke further commented, “The results seen with the Claret Medical system are striking. They clearly show that by removing embolic debris from cerebral circulation when performing TAVR, we can dramatically reduce both the quantity and volume of brain lesions.”

In commentary on the CLEAN TAVI findings to Cardiac Interventions Today, Douglas E. Drachman, MD, stated, “While larger clinical trials will be required to validate these promising findings, there is significant hope that the routine application of cerebral protection may reduce adverse neurologic events with TAVR.” Dr. Drachman is Director, Cardiology and Interventional Cardiology Fellowship Programs at Massachusetts General Hospital Institute for Heart, Vascular, and Stroke Care in Boston, Massachusetts.