But these preliminary findings require confirmation in larger trials, says an expert.
A novel stent known as the Barrel vascular reconstruction device (VRD) appears to be a promising treatment for wide-neck bifurcation aneurysms, according to a European postmarketing analysis published online February 6, 2018 ahead of print in the Journal of NeuroInterventional Surgery.
“Wide-necked bifurcation aneurysms are a challenge to treat with previous technology,” Ajith J. Thomas, MD (Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA), who did not take part in the study, told Neurovascular Exchange. “While Y-stenting can be successful,” he said, “there is considerable procedural complexity and increase in complications, as highlighted in recent publications.”
The Barrel VRD (Medtronic/Covidien) is a self-expanding, fully retrievable, laser-cut nitinol stent with a bulged central component, allowing for greater neck coverage. Another feature is its double spiral strut construction, providing a hinged element that can conform to tortuous anatomy. It also has 12 platinum marker bands, and the proximal marker band attaches to a wire that pushes the device through a 0.021-in inner diameter microcathether to the intended treatment site.
For the Barrel VRD trial, a multicenter postmarketing registry, investigators led by Benjamin Gory, MD, PhD (University Hospital of Nancy, France), enrolled 20 patients with wide-neck bifurcation aneurysms from December 2013 to December 2014. Of these patients, 19 had the device implanted in 19 aneurysms: 8 in the middle cerebral artery, 4 in the anterior communicating artery, 1 in the internal carotid artery terminus, and 4 in the basilar artery. Come height was 5.7 ± 1.91 mm, with a neck length of 4.8 ± 1.35 mm, and dome-to-neck ratio of 1.6 ± 2.0. Coiling was performed in all cases.
The primary effectiveness endpoint was successful aneurysm treatment measured by digital subtraction angiography, with a Raymond-Roy occlusion grade of 1 or 2 in the absence of retreatment; parent artery stenosis (> 50%); or target aneurysm rupture at 12 months. The primary safety endpoint was the absence of neurological death or major stroke at 12 months. The stent showed high rates of both efficacy and safety.
12-Month Outcomes of Barrel Coiling
Primary Effectiveness Endpoint
Primary Safety Endpoint
Among the 15 patients who achieved the primary efficacy endpoint, 12 had complete occlusions and 3 had neck remnants.
“This device, if successful, would allow placement of a single stent device for coil-assisted treatment of wide-necked bifurcation aneurysms,” said Thomas. The outcomes data are difficult to compare to those of other treatment options, however, since “all of the newer devices [for this indication] are in their infancy [and have] conflicting data. The occlusion and complication rates appear to be similar or slightly worse than other devices,” he commented. The study itself had no comparison group, either to other devices or standard of care (ie, Y- or X-stenting).
Thomas noted some concerns about the Barrel VRD and the study. “I do have questions about the ability to recapture and reposition the device,” he said, “because it is crucial that the mid portion of the stent is aligned with the aneurysm neck.”
In addition, he noted that the study is very small, with only 19 subjects, and was a registry trial. This means “reporting and follow-up were somewhat voluntary, which is likely to underestimate complication and failure rates compared to an adjudicated randomized trial,” Thomas explained.
Essentially, he said, this is a preliminary study, and outcomes in a larger group of patients are needed to truly evaluate the utility of this new device.
Gory B, Blanc R, Turjman F et al. The Barrel vascular reconstruction device for endovascular coiling of wide-necked intracranial aneurysms: a multicenter, prospective, postmarketing study. J NeuroInerv Surg. 2018;Epub ahead of print.
Gory and Thomas report no relevant conflicts of interest.