ATLAS
(2020)Objective
Evaluate the safety and efficacy of the Neuroform Atlas Stent System for stent-assisted coiling of wide-neck, saccular, intracranial aneurysms in the anterior circulation.
Study Summary
• Major ipsilateral stroke or neurological death occurred in 4.4%.
• The study met both primary safety and efficacy endpoints and supported FDA premarket approval.
Intervention
Prospective, multicenter, open-label, single-arm IDE trial across 25 US centers. N=182 patients with wide-neck anterior circulation aneurysms (neck ≥4 mm or dome-to-neck ratio <2) were treated with the Neuroform Atlas stent and detachable coils. Patients received dual antiplatelet therapy prior to the procedure. Primary efficacy: Raymond-Roy Class 1 occlusion at 12 months without retreatment or parent artery stenosis. Primary safety: major ipsilateral stroke or neurological death within 12 months.
Inclusion Criteria
• Age 18–80 years
• Unruptured, wide-neck, saccular aneurysm in anterior circulation
• Neck ≥4 mm or dome-to-neck ratio <2
• Parent vessel diameter between 2.0–4.5 mm
Study Design
Arms: Single-arm (all patients received Neuroform Atlas stent and adjunctive coiling)
Patients per Arm: 182
Outcome
• Composite efficacy (occlusion without retreatment or stenosis): 84.7%; p<0.001
• Major ipsilateral stroke: 4.4%
• Neurological death: 0.5%
• Retreatment: 3.8%
• Parent artery stenosis >50%: 1.3%
• Subarachnoid hemorrhage: 3.8%
• Procedural technical success: 100%
Bottom Line
The Neuroform Atlas Stent met both FDA performance goals in 182 patients with wide-neck anterior circulation aneurysms. Primary efficacy (complete occlusion + no retreatment + no stenosis at 12mo): 84.7% (goal >50%; P<0.001). Primary safety (major ipsilateral stroke/neurological death): 4.4% (goal <20%; P<0.001). Technical success 100%. Complete occlusion on 12-month DSA: 88.2%. Only 2.2% had symptomatic long-term deficit or death. FDA PMA granted May 2019.
Major Points
- Primary efficacy met: 84.7% complete occlusion + no retreatment + no stenosis (goal >50%; P<0.001).
- Primary safety met: 4.4% major stroke/neurological death (goal <20%; P<0.001). Only 2.2% with long-term deficit.
- 100% technical success (182/182). 84.1% single stent, 15.9% two stents.
- 12-month DSA: 88.2% Raymond-Roy class 1 (complete). RR 1+2: 96.1%.
- Progressive occlusion: 94.7% maintained or improved at 12 months vs immediate post-procedure.
- Low retreatment (3.8%) and parent artery stenosis (1.3%).
- mRS 0-1 at 12 months: 91.6%. mRS 0-2: 94.6%.
- 182 patients, 25 US centers, single-arm IDE trial. Stryker-funded.
- Anterior circulation only (AComA 35%, ICA-ophthalmic 16%, MCA bifurcation 15%).
- Mean aneurysm neck 4.1mm, mean size 6.1mm. 73% female, mean age 60.
Study Design
- Study Type
- Prospective, multicenter, single-arm, open-label
- Randomization
- No
- Blinding
- None (open-label); independent imaging and clinical adjudication
- Sample Size
- 182
- Follow-up
- 12 months
- Centers
- 25
- Countries
- United States
Primary Outcome
Definition: Complete aneurysm occlusion (Raymond-Roy class 1) at 12 months without retreatment or parent artery stenosis
| Control | Intervention | HR/OR | P-value |
|---|---|---|---|
| 84.7% | - (78.6%–90.9%) | <0.001 |
Limitations & Criticisms
- Single-arm design without randomization
- Limited to anterior circulation aneurysms
- No comparison to flow-diverter or other treatment options
- Follow-up limited to 12 months
Citation
Zaidat OO, Jankowitz BT, et al. Stroke. 2020;51:2087–2094.