Neuroform Atlas Stent for Treatment of Middle Cerebral Artery Aneurysms: 1-Year Outcomes From Neuroform Atlas Stent Pivotal Trial.

BACKGROUND Heterogeneous effect of endovascular aneurysm therapy has been observed across different anatomic locations. There is a paucity of data for stent-assisted coiling of middle cerebral artery (MCA) aneurysms. OBJECTIVE To present the results of the MCA aneurysm group from the Neuroform Atlas (Stryker Neurovascular) investigational device exemption (IDE) trial. METHODS The Atlas IDE trial is a prospective, multicenter, single-arm, open-label study of wide-neck aneurysms (neck ≥ 4 mm or dome-to-neck ratio < 2) in the anterior circulation treated with the Neuroform Atlas Stent and approved coils. Follow-up was obtained immediately postprocedure and 2, 6, and 12 mo postoperatively. We herein describe safety and efficacy outcomes, and functional independence of the subjects with aneurysms from all segments of MCA. RESULTS A total of 35 patients were included (27 MCA bifurcation, 5 M1, 3 M2). The mean aneurysm size was 6.0 ± 1.8 mm, and the mean neck was 4.4 ± 1.2 mm. Technical procedural success was achieved in all patients. A total of 26 patients had follow-up digital subtraction angiography available at 12 mo, with 80.8% (21/26) having complete aneurysm occlusion. Twelve-month safety data were collected for 91.4% (32/35), 8.5% (3/35) had primary safety endpoint, all 3 major ischemic strokes. Mortality occurred in 2 patients beyond 30 d unrelated to procedure (1 gallbladder cancer and 1 fentanyl intoxication). At 1 yr, modified Rankin Score was 0 to 2 in 84.4% (27/32), 3 in 9.4%, and 3 patients were missing. Approximately 5.7% (2/35) of patients were retreated at 12 mo. CONCLUSION Stent-assisted coiling with the Neuroform Atlas Stent is a viable alternative to clipping for selected MCA aneurysms. Complete aneurysm occlusion rates have improved compared to historical data. Proper case selection can lead to acceptable endovascular results.