Early Versus Delayed Flow Diversion for Ruptured Intracranial Aneurysms: A Meta-Analysis

Objective The use and timing of flow diversion for aneurysmal subarachnoid hemorrhage is controversial. The objective of this study is to perform a meta-analysis and systematic review to compare overall complication rate between early versus delayed flow diversion for ruptured aneurysms. Methods A literature search for all eligible articles was performed using PubMed, Cochrane, and Web of Science databases. The primary outcome was the overall complication rate (any complication in the perioperative period), and secondary outcomes were 1) hemorrhage and 2) stroke/death (all hemorrhagic/ischemic strokes and/or death). Results Thirteen articles including 142 patients met inclusion criteria. Eighty-nine (62.7%) patients underwent early deployment of flow diverters (i.e., 2 days or less). The odds ratio for overall complication rate with early versus delayed flow diversion was 0.95 (95% confidence interval [CI] 0.36–2.49, P  = 0.42). The odds ratio for the secondary outcome of hemorrhagic complication for early versus delayed flow diversion was 1.44 (95% CI 0.45–4.52, P  = 0.87) and of stroke/death was 1.67 (95% CI 0.5–4.9, P  = 0.69). The odds ratio of early versus delayed flow diversion for blister/dissecting/fusiform aneurysms was 0.82 (95% CI 0.29–2.30) and for saccular/giant aneurysms was 2.23 (95% CI 0.17–29.4). At last follow-up, 71.6% of patients had good performance status (modified Rankin Scale score 0–2), and the rate of angiographic aneurysm occlusion was 90.2%. Conclusions This meta-analysis did not show a difference in overall complication rate between early versus delayed flow diversion for ruptured aneurysms. Early flow diversion for ruptured blister/fusiform/dissecting aneurysms carries a lower risk of aneurysm rerupture and overall complications as compared with that for ruptured saccular/giant aneurysms.