RT Journal Article SR Electronic T1 Delayed thromboembolic events after coiling of unruptured intracranial aneurysms in a prospective cohort of 335 patients JF Journal of NeuroInterventional Surgery JO J NeuroIntervent Surg FD BMJ Publishing Group Ltd. SP 534 OP 540 DO 10.1136/neurintsurg-2020-016654 VO 13 IS 6 A1 Laurent Pierot A1 Coralie Barbe A1 Denis Herbreteau A1 Jean-Yves Gauvrit A1 Anne-Christine Januel A1 Fouzi Bala A1 Frédéric Ricolfi A1 Hubert Desal A1 Stéphane Velasco A1 Mohamed Aggour A1 Emmanuel Chabert A1 Jacques Sedat A1 Denis Trystram A1 Gaultier Marnat A1 Sophie Gallas A1 Georges Rodesch A1 Frédéric Clarençon A1 Chrysanthi Papagiannaki A1 Phil White A1 Laurent Spelle YR 2021 UL http://jnis.bmj.com/content/13/6/534.abstract AB Background Coiling is the first-line treatment for the management of unruptured intracranial aneurysms (UIAs), but delayed thromboembolic events (TEEs) can occur after such treatment. ARETA (Analysis of Recanalization after Endovascular Treatment of Intracranial Aneurysm) is a prospective multicenter study conducted to analyze aneurysm recanalization. We analyzed delayed TEEs in the UIA subgroup.Methods Sixteen neurointerventional departments prospectively enrolled patients treated for ruptured and unruptured aneurysms between December 2013 and May 2015. Participant demographics, aneurysm characteristics, and endovascular techniques were recorded. Data were analyzed from participants with UIA treated by coiling or balloon-assisted coiling. We assessed the rates, timing, management, clinical outcomes, and risk factors for delayed TEEs using univariable and multivariable analyses.Results The rate of delayed TEEs was 2.4% (95% CI 1.0% to 4.6%) in patients with unruptured aneurysms, with all events occurring in the week following the procedure. In multivariate analysis, two factors were associated with delayed TEEs: autosomal dominant polycystic kidney disease (ADPKD): 20.0% in patients with ADPKD vs 1.9% in patients without ADPKD (OR 27.3 (95% CI 3.9 to 190.2), p=0.0008) and post-procedure aneurysm remnant: 9.4% in patients with post-procedure aneurysm remnant vs 1.6% in patients with adequate occlusion (OR 9.9 (95% CI 1.0 to 51.3), p=0.006). We describe modalities of management as well as clinical outcomes.Conclusions Delayed TEE is a relatively rare complication after coiling of UIAs. In this series, all occurred in the week following the initial procedure. Two factors were associated with delayed TEE: ADPKD and aneurysm remnant at procedure completion.Clinical trial registration NCT01942512 Data are available upon reasonable request by contacting the corresponding author.