Clinical Outcomes of Microvascular Clipping Compared to Endovascular Coiling for Ruptured Anterior Communicating Artery Aneurysms

Abstract

A ruptured intracranial aneurysm is a devastating pathology that is associated with significant morbidity and mortality. The anterior communicating artery (ACOM) is the most common location to have an intracranial aneurysm form and rupture. The two management options for ruptured intracranial aneurysms include microsurgical clipping and endovascular coiling. The clinical outcomes of microsurgical clipping and endovascular coiling for ruptured ACOM aneurysms remains unclear. The aim of the research presented in this thesis was to investigate the clinical outcomes, including functional outcomes, treatment efficacy and safety of microsurgical clipping and endovascular coiling for the management of ruptured ACOM aneurysms. A search for published and unpublished literature included PubMed, Embase, Scopus, Cochrane Central Register of Controlled Trials, International Clinical Trial Registry, Australia and New Zealand Clinical Trial Registry Search Strategy and ClinicalTrials.gov. Studies were included if they explored the functional outcomes and/or safety of microsurgical clipping and endovascular coiling for ruptured ACOM aneurysms. Eligible studies were critically appraised by two reviewers using appropriate JBI tools to assess methodological qualitied. Where possible, data from included studies was meta-analysed using a random effects Mantel-Haenszel model. Sensitivity analyses were performed using a fixed effect model. Effect measures included odds ratio and risk difference where no events were recorded. The search yielded 818 records. Following screening of titles and abstracts against the review inclusion criteria, 25 articles were retrieved for full-text screening. Of these, 11 studies, all of which were non-randomised studies (2 quasi-experimental and 9 retrospective cohort studies), were included. Overall, these studies fulfilled the majority of the quality appraisal criteria. For the primary outcome (favourable functional outcomes), analysis revealed overall no statistically significant difference between microsurgical clipping and endovascular coiling (79.4% versus 73.6%, OR 1.11, 95% CI 0.78 – 1.57, p=0.56). Results from the quasi-experimental studies demonstrated favourable outcomes in the clipping group were non-significantly higher than the coiling group (86.2% versus 80.4%, OR 2.26, 95% CI 0.6-8.52, p=0.23). In cohort studies, favourable outcomes in the clipping group were non-significantly higher than the coiling group (78.9% versus 72.3%, OR 1.05, 95% CI 0.71-1.53, p=0.23). For the secondary outcomes of recurrence and complications, overall no statistically significant difference was found between clipping versus coiling (recurrence - 4.6% versus 5.7%, RD 0.00, 95% CI -0.06 – 0.06, p=0.47; complications- 21.6% versus 14.2%, OR 1.00 95% CI 0.49 – 2.05, p=1.00). Results from the quasi-experimental studies demonstrated recurrence was non-significantly higher in the clipping group compared to the coiling group (17.2% versus 0%, RD =0.15 95% CI -0.04-0.34, p=0.16). In cohort studies, recurrence was non-significantly higher in the coiling group versus clipping group (6.7% versus 3.4%, RD = -0.02 95 CI -0.07-0.03, p=0.92). Results from the quasi-experimental study demonstrated complications were non-significantly higher in the clipping group compared to the coiling group (20% versus 6.67%, OR =3.50 95% CI 0.32-38.23, p=0.30). In cohort studies, complications were again non-significantly higher in the clipping group versus the coiling group (21.6% versus 14.5%, OR=8.38 95% CI 0.42-1.93, p<0.001). Occlusion was found to be significantly higher in the clipping group compared to coiling (95% versus 75%, OR 7.01, 95% CI 2.82 – 17.45, p=<0.0001). Results from the quasi-experimental study demonstrated occlusion was similar in the clipping group compared to the coiling group (93.3% versus 86.7%, OR =2.15 CI 0.17-26.67, p=0.55). In cohort studies, occlusion was significantly higher in the clipping group versus the coiling group (94.9% versus 74.2%, OR=8.38 CI 31.5-22.28, p<0.001). In conclusion, microsurgical clipping and endovascular coiling appear to be equally effective and safe for the treatment of ruptured ACOM aneurysms. Both options should be considered when managing patients with this pathology.