DEFLECT III: TAVR Neuroprotection Device Safely Reduces Lesion Volume

SAN DIEGO, CA—Use of a novel neuroprotection during TAVR is safe and has the potential to eradicate cerebral lesions that cause stroke, according to results of a small study presented March 15, 2015, at the American College of Cardiology/i2 Scientific Session. 

The TriGuard device (Keystone Heart; Caesarea, Israel) consists of a nitinol single-wire frame and a mesh filter (pore size 130 μm). It is delivered femorally with a 9-Fr sheath, positioned across all cerebral vessels, and maintained by a stabilizer.

 Results from DEFLECT I—presented at EuroPCR 2013 in Paris, France—showed that an earlier iteration of the device failed to reduce the number of cerebral lesions during TAVR but did decrease the volume of such lesions.

For DEFLECT III, Alexandra J. Lansky, MD, of the Yale University School of Medicine (New Haven, CT), presented an intention-to-treat analysis of 30-day follow up on 83 patients who were randomized to TAVR at 12 centers in 5 countries with (n = 45) or without (n = 38) the TriGuard system. Data collection in the trial is still ongoing.

Baseline characteristics were well matched between the groups and representative of a typical TAVR patient population. CoreValve (Medtronic) was used in about a third of patients, with a Sapien device (Edwards LifeSciences) being used in the rest. Also, fluoroscopy time was slightly longer with the TriGuard (28.2 vs 18.6 minutes; P < .001), but this was expected given the extra procedural step.

No Increase in In-hospital MACCE Seen

Although in-hospital safety outcomes were available in all patients, 29% and 34% of study and control patients, respectively, were lost to pre-discharge MRI follow-up for reasons including stroke, refusal, permanent pacemaker implantation, or death.

Technical success was achieved in 87% of the study group (6 patients lost complete coverage), and TAVR success did not differ between the study arms. The primary safety endpoint of i-hospital MACCE (death, stroke, life-threatening or disabling bleeding, acute kidney injury, and major vascular complications) and its individual components were comparable whether or not patients were treated with TriGuard (table 1).

On diffusion-weighted MRI, the average number of new lesions reported per patient were 4.5 and 4.0 for TriGuard and control patients, respectively. Use of the study device reduced single and maximum lesion volumes by 19% in the intention-to-treat analysis and by 41% and 45%, respectively, in the per-treatment analysis of patients with complete cerebral coverage. Most importantly, complete freedom from ischemic brain lesions for TriGuard patients was 22% in the intention-to-treat analysis and 27% in the per-treatment analysis compared with 12.5% for controls.

New neurologic findings (defined as the change in NIH stroke scale score from baseline to pre-discharge) occurred in 14.3% of controls and 4.9% of Triguard patients.

On average, MoCA (Montreal Cognitive Assessment) scores improved in the TriGuard arm and worsened in the control arm.

“DEFLECT III will benchmark event rates for a future randomized trial that will be able to truly examine the potential benefits of the TriGuard device,” Dr. Lansky concluded.

Mechanisms, Benefit Yet to be Fully Understood

In a discussion after the presentation, panelist Ian Meredith, MBBS, PhD, of Monash Medical Centre Clayton (Melbourne, Australia), asked what Dr. Lansky and colleagues would do differently in a big trial.

Understanding the mechanisms and benefit of the device better will be paramount to future success, Dr. Lansky replied. “We need to establish the magnitude of improvement in terms of the neurocognitive improvement, surrogate endpoints, [and] reduction in the volumes in the absence of brain lesions,” she said.

Dr. Lansky explained that the study was not able to fully look into the distribution of observed brain lesions, but historically, she said, distribution has been a “free for all” with vessels found throughout the brain and in all 3 vessels. Hence, “coverage of all three vessels is important,” she concluded.
 

Source:
Lansky AJ. First report of the DEFLECT III trial results: a prospective randomized evaluation of the TriGuard HDH Embolic DEFLECTion Device during transcatheter aortic valve replacement. Presented at: American College of Cardiology/i2 Scientific Session; March 15, 2015; San Diego, CA.

Disclosures:

• Dr. Lansky reports receiving consulting fees/honoraria from CardioDX, owning interest in Keystone Heart, and serving on the speaker’s bureaus for AstraZeneca, Daiichi Sankyo, Eli Lilly, and Merck.
• Dr. Meredith reports receiving consulting fees/honoraria from Boston Scientific, Guided Delivery Systems, and Medtronic Vascular.

Related Stories:

• Deflection Device Reduces Volume, Not Number, of Cerebral Lesions During TAVR
• Embolic Debris Captured by Filters in Three-Quarters of TAVR Patients
• Cerebral Protection Device Reduced Brain Lesions, Neurological Events After TAVR