Safety and effectiveness of microsurgical clipping, endovascular coiling, and stent assisted coiling for unruptured anterior communicating artery aneurysms: a systematic analysis of observational studies

Treatment outcomes for unruptured anterior communicating artery (ACoA) aneurysms are not well established. We aimed to investigate the safety and effectiveness of microsurgical clipping (MC), endovascular coiling (EC), and stent assisted coiling (SAC) of unruptured ACoA aneurysms to aid pretreatment clinical decisions.A systematic review of the literature was conducted using the Ovid Medline and EMBASE electronic databases, encompassing all English language studies reporting treatment outcomes for unruptured ACoA aneurysms published between 2005 and 2015. The analyses were directed towards patient focused outcomes: good therapeutic outcome (Glasgow Outcome Score of 5 (GOS 5), modified Rankin Scale (mRS) score of 0-1), poor therapeutic outcome (GOS 1-4, mRS 2-6), 30 day mortality, recurrence/retreatment rates, and post-treatment subarachnoid hemorrhage (SAH).14 studies with 862 treated aneurysms were included (EC, n=372; MC, n=401; SAC, n=89). EC resulted in significantly lower treatment related morbidity compared with MC or SAC (EC 0.8%, MC 4.4%, SAC 7.9%; p=0.001); treatment related mortality occurred in 0%, 0.3%, and 1.1%, for EC, MC, and SAC, respectively. MC resulted in significantly lower angiographic recurrence (EC 7.2%, MC 0%, SAC 12.3%; p<0.001) and retreatment (EC 4.9%, MC 0%, SAC 6.8%; p=0.001). SAH from the treated aneurysm was not reported with any treatment modality.While there are limitations to the data, EC resulted in a more favorable clinical outcome, and MC resulted in more robust aneurysm repair, for unruptured ACoA aneurysms. SAC had a higher treatment morbidity risk than EC, without reduction in retreatment rate. All treatments were effective in preventing SAH. The current pooled analysis of treatment outcomes provides a useful aid to pretreatment clinical decision making.