The Source for Neurovascular News and Education

October 23, 2019

 

Results out to 18 months demonstrate a high occlusion rate with good durability and few complications.

 

Braided stents can successfully be used to treat bifurcation aneurysms with excellent durability out to 18 months, according to a single-center analysis published online recently in the Journal of NeuroInterventional Surgery.

If these results are confirmed in multicenter trials with a longer duration of follow-up, it suggests that niche devices for this indication are essentially unnecessary, said senior author Jason D. Wenderoth, MD (Prince of Wales Private Hospital and Liverpool Hospital, New South Wales, Australia).

 

“Aneurysms at bifurcations . . . have historically been problematic for interventional neuroradiologists for a few reasons, including increased risk of parent vessel compromise/occlusion, difficulty achieving a good angiographic occlusion, and poorer durability,” he told Neurovascular Exchange in an email. “Although devices such as hypercompliant balloons and laser-cut stents have allowed some aneurysms to be treated endovascularly that would previously have required open repair, the results have often not been durable, requiring repeat procedures or, in some cases, bailout surgery.”

 

More recently, certain niche devices have entered the market that are specifically designed to treat bifurcation aneurysms. The downside of these devices, explained Wenderoth, is that they “are often difficult to deploy, complicated to use, require large-bore catheter systems, or are difficult to visualize on fluoroscopy. [Also] they are not a part of the interventionalist's day-to-day skill set.”

 

Stents, on the other hand, are very familiar to neurointerventionalists. Braided stents in particular are both commonplace and “deliverable through low-profile catheter systems, and [they] offer several technical advantages over other devices,” he said.

 

To find out how braided stents perform in this setting, Wenderoth and colleagues assessed 6-month follow-up data for 59 bifurcation aneurysms and 18-month follow-up data for 58 bifurcation aneurysms that were treated using elective braided-stent-assisted coil embolization at one of three Australian neurovascular centers. Of these aneurysms, 17 underwent T- or Y-shaped multistent constructs.

 

Satisfactory aneurysm occlusion rates occurred in almost all cases at 6 and 18 months. In addition, good neurological outcomes, defined as an mRS 0-1, were achieved in the vast majority of patients. Results were similar for the 17 patients treated with multiple stent constructs.

 

Outcomes of Braided Stents

 

6 Months

(n = 59)

18 Months

(n = 58)

Satisfactory Occlusion

97%

98%

mRS 0-1

95%

 

The overall complication rate was 13%. Intraprocedural thromboembolic events occurred in 5% of patients and delayed events in 2%. Technical complications occurred in 5%.

 

A Great Multitasker

 

According to Wenderoth, the findings indicate that “using braided stents for repair of bifurcation aneurysms has a very high technical success rate (approaching 100%), achieves satisfactory angiographic closure of the aneurysm at the time of treatment in almost all cases, and provides durable repair out to at least 18 months posttreatment, with a negligible rate of aneurysm recurrence.

 

“This is in contrast with the use of laser-cut stents,” he continued, “which have a significantly higher failure rate, both at treatment and at long-term follow-up. The safety profile for using braided stents appears to be at least as good, if not better than open repair or other endovascular options.”

 

Wenderoth pointed out that braided stents have been used regularly to treat bifurcation aneurysms since about 2010 or 2011 in countries where they are readily available. This includes Europe, Australia, Canada, and the United Kingdom. But experience is less in the United States, where they have only been on the market for a year or so. They are not available at all in some countries, such as Japan.

 

“When comparing braided stenting with other endovascular options, it is technically comparable in difficulty/complexity to using a balloon or laser-cut stent,” he said. “However, it is considerably less difficult than using the specifically designed niche devices that have entered the market, all of which are unproven in their safety and efficacy.”

 

Wenderoth added that the success of braided stents for the treatment of bifurcation aneurysms suggests that there is really no need to pursue development of additional niche devices. “Braided stents provide a ‘one size fits all’ approach,” he concluded. “In our service, we use braided stents for almost all our bifurcation aneurysms because of their safety, simplicity, and reliability.”

 

“With the growing number of interventional neuroradiologists worldwide each doing fewer and fewer cases, it is critical that device companies work towards technological convergence, such a single device that is simple to use, can be deployed in a multitude of ways, and/or used for several purposes to ensure operator comfort and familiarity with the device,” he stressed.

 

Braided stents are great examples of multitaskers, he said, because they are malleable and can be shaped by application of traction or pressure to conform to various vessel configurations. This is the type of device that companies should be investing in, he said, so that “aneurysm treatment [is] just as safe in the hands of the person treating 20 aneurysms a year as it is in the hands of the person treating 200.”

 

Ideally, use of braided stents for this indication should be evaluated in a multicenter trial with a longer follow-up period, Wenderoth suggested. He and his team have already obtained ethics approval to continue to follow-up their patients.

 


Source:

Cheung NK, Chiu AH, Cheung A, et al. Long term follow-up of bifurcation aneurysms treated with braided stent assisted coiling and complex T- and Y- stent constructs. J NeuroInterv Surg.  2017;Epub ahead of print.

 

Disclosures:

Wenderoth reports having speaking/consulting agreements with Medtronic, Microvention and Stryker and being a stockholder in Medtronic and Stryker.