Immediate post-operative aneurysm occlusion after endovascular treatment of intracranial aneurysms with coiling or balloon-assisted coiling in a prospective multicenter cohort of 1189 patients: Analysis of Recanalization after Endovascular Treatment of intracranial Aneurysm (ARETA) Study.

BACKGROUND: Coiling, including balloon-assisted coiling (BAC), is the first-line therapy for ruptured and unruptured aneurysms. Its efficacy can be clinically evaluated by bleeding/rebleeding rate after coiling, and anatomically evaluated by aneurysm occlusion post-procedure and during follow-up. We aimed to analyze immediate post-coiling aneurysm occlusion and associated factors within the Analysis of Recanalization after Endovascular Treatment of intracranial Aneurysm (ARETA) population.
METHODS: Between December 2013 and May 2015, 16 neurointerventional departments prospectively enrolled participants treated for ruptured and unruptured aneurysms (ClinicalTrials.gov: NCT01942512). Participant demographics, aneurysm characteristics, and endovascular techniques were recorded. In patients with aneurysms treated by coiling or BAC, immediate post-operative aneurysm occlusion was independently evaluated by a core lab using a 3-grade scale: complete occlusion, neck remnant, and aneurysm remnant.
RESULTS: Of 1135 participants (age 53.8±12.8 years, 754 women (66.4%)), 1189 aneurysms were analyzed. Treatment modality was standard coiling in 645/1189 aneurysms (54.2%) and BAC in 544/1189 (45.8%). Immediate post-operative aneurysm occlusion was complete occlusion in 57.8%, neck remnant in 34.4%, and aneurysm remnant in 7.8%. Adequate occlusion (complete occlusion or neck remnant) was significantly more frequent in aneurysms with size <10 mm (93.1% vs 86.3%; OR 1.8, 95% CI 1.1 to 3.2; p=0.02) and in aneurysms with a narrow neck (95.8% vs 89.6%; OR 2.5, 95% CI 1.5 to 4.1; p=0.0004). Patients aged <70 years had significantly more adequate occlusion (92.7% vs 87.2%; OR 1.9, 95% CI 1.1 to 3.4; p=0.04).
CONCLUSIONS: Immediately after aneurysm coiling, including BAC, adequate aneurysm occlusion was obtained in 92.2%. Age <70 years, aneurysm size <10 mm, and narrow neck were factors associated with adequate occlusion. TRIAL REGISTRATION NUMBER: NCT01942512, http://www.clinicaltrials.gov. © Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.