Coiling Is Not Superior to Clipping in Patients with High-Grade Aneurysmal Subarachnoid Hemorrhage: Systematic Review and Meta-Analysis.

Background: Outcomes of coiling embolization versus clipping for patients with high-grade aneurysmal subarachnoid hemorrhage (aSAH) have not been previously compared. We reviewed current evidence regarding the safety and efficacy of clipping versus coiling for high-grade aSAH.

Methods: We conducted a meta-analysis of studies that compared clipping with coiling in patients with high-grade aSAH published from January 1999 to February 2016 in Medline, Embase, and Cochrane databases based on PRISMA inclusion and exclusion criteria. Binary outcome comparisons between clipping and coiling were described using odds ratios (ORs).

Results: Three randomized controlled trials (RCTs) and 16 observational studies were included. There was no statistical difference in good outcome rates between the clipping and coiling groups (OR, 1.44; 95% confidence interval [CI], 0.97-2.13). Subgroup analysis showed no significant difference between the 2 treatments in non-RCTs (OR, 1.49; 95% CI, 0.95-2.36) and RCTs (OR, 1.15; 95% CI, 0.59-2.25). Coiling was associated with higher mortality (OR, 0.55; 95% CI, 0.41-0.75). Lower mortality was associated with clipping in non-RCTs (OR, 0.54; 95% CI, 0.40-0.74), but there was no difference in the RCTs (OR, 0.79; 95% CI, 0.19-3.39). Coiling was not associated with lower rates of complications including rebleeding (OR, 0.62; 95% CI, 0.30-1.29), ischemic infarct (OR, 0.89; 95% CI, 0.53-1.49), symptomatic vasospasm (OR, 0.76; 95% CI, 0.45-1.29), or shunt-dependent hydrocephalus (OR, 1.33; 95% CI, 0.52-3.40).

Conclusion: The outcome with coiling is not superior to clipping in patients with high-grade aSAH; moreover, coiling has a greater risk of mortality.