Predictors of recurrence and complications for the endovascular treatment of unruptured middle cerebral artery aneurysm: A high-volume center experience over 12 years

Object: To assess the safety and efficacy of endovascular treatment (EVT) of unruptured middle cerebral artery (MCA) aneurysms in a retrospective cohort in a high-volume center. Predictors of complications and recurrence were determined.

Methods: Retrospectively reviewed our database of prospectively collected information for all patients with unruptured MCA aneurysms that were treated by endovascular approach from March 2008 to December 2020. A multivariate analysis was conducted to identify predictors of complications and recurrence.

Results: Three hundred and fifty-one patients with 370 unruptured MCA aneurysms underwent EVT were included in this study. Seventy-three aneurysms (19.7%) were treated by coiling without stent, 297 (80.3%) with stent-assisted coiling. The procedures were performed with a technical success rate of 100%. Procedure-related neurological complications occurred in 15 patients (4.1%), including 1 patient died from post-procedural stent thrombosis. Age ≥ 65 years (P = 0.039; OR = 3.400; 95% CI, 1.065-10.860) and aneurysm size ≥ 5 mm (P = 0.009; OR = 15.524; 95% CI, 1.988-121.228) were significantly associated with ischemic complications of EVT. Three hundred and six aneurysms were (87.2%) completed image follow-up (235 DSA and 71 CE-MRA). The median angiographic follow-up time were 7.0 ± 4.3 months (range from 1 to 88 months). Follow-up angiograms showed that 249 aneurysms (81.4%) were completed occluded, 29 aneurysms (9.5%) were improved, 17 aneurysms (5.6%) were stable, and 11 aneurysms (3.6%) were recanalized and 10 of them accepted retreatments. Aneurysm size ≥ 10 mm was a predictor of recanalization (P = 0.004; OR = 11.213; 95% CI, 2.127-59.098) and stent-assisted coiling can significantly reduce recanalization (P = 0.004; OR = 0.105; 95% CI, 0.023-0.479).

Conclusions: EVT is a safe and effective therapeutics for unruptured MCA aneurysms management, and provides durable aneurysm occlusion rate during follow-up. Large MCA aneurysms have higher recurrence and ischemic complications risk after EVT. Stent-assisted coiling can significantly reduce the recurrence rate without increasing the risk of complications.