Endovascular coiling versus surgical clipping for aneurysmal subarachnoid hemorrhage: A meta-analysis of randomized controlled trials

Background: Aneurysmal subarachnoid hemorrhage is a relatively rare cause of stroke, carrying a bad prognosis of mortality and disability. The current standard procedure, neurosurgical clipping, has failed to achieve satisfactory outcomes. Therefore, endovascular detachable coils have been tested as an alternative. This meta-analysis was aimed to compare the outcomes of surgical clipping and endovascular coiling in aneurysmal subarachnoid hemorrhage. Materials and Methods: Relevant randomized trials up to June 2018 were identified from Medline, Central, and Web of Science. Data for poor outcomes (Modified Rankin Scale [mRS] scores 3 to 6) at 2-3 months, 1 year, and 3-5 years were extracted and analyzed as odds ratios (ORs) with 95% confidence intervals (CIs), using RevMan software. Results: Five studies (2780: 1393 and 1387 patients in the coiling and clipping arms, respectively) were included in the current analysis. The overall effect estimate favored endovascular coiling over surgical clipping in terms of reducing poor outcomes (death or dependency, mRS > 2) at 1 year (OR = 0.67, 95% CI: 0.57-0.79)and 3-5 years (OR = 0.8, 95% CI: 0.67- 0.96). Moreover, coiling was associated with a significantly lower rate of cerebral ischemia (OR = 0.37, 95% CI: 0.16-0.86). Postprocedural mortality (OR = 0.79, 95% CI: 0.6-1.05) and rebleeding (OR = 1.15, 95% CI: 0.75-1.78) rates were comparable between the two groups. However, technical failure was significantly more common with coiling interventions than with clipping surgeries (OR = 2.84, 95% CI: 1.86-4.34). Conclusion: Our analysis suggests that coiling can be a better alternative to clipping in terms of surgical outcomes. Further improvements in the coiling technique and training may improve the outcomes of this procedure.