A randomized trial comparing endovascular and surgical management of ruptured intracranial aneurysms excluded from previous trials.

Objective: Many patients with ruptured intracranial aneurysms (RIAs) underrepresented or excluded from previous randomized controlled trials (RCTs) comparing surgery with endovascular treatment (EVT) are still considered for surgical clipping, but the best management of these patients remains unknown.

Methods: The International Subarachnoid Aneurysm Trial-2 was a randomized trial comparing surgical versus EVT of RIAs considered for surgical clipping, despite the results of previous RCTs, and also eligible for EVT. The primary endpoint was death or dependency according to the modified Rankin Scale score (mRS score > 2) at 1 year. Secondary endpoints included 1-year angiographic results and length of hospital stay. The primary hypothesis was that endovascular management would decrease the number of poor outcomes (mRS score > 2) from 30% to 23%, necessitating 1896 patients. The trial was interrupted after 10 years because of slow recruitment. Primary analysis was by intent-to-treat. There was no blinding.

Results: From November 2012 to December 2022, 270 patients were recruited at 6 North American and European centers. After exclusions, 263 patients were randomly allocated to receive surgery (n = 133) or EVT (n = 130). There were 12 crossovers (9 from surgery to EVT). The primary outcome was reached in 40 of 133 surgical patients (30%, 95% CI 23%-38%) compared with 35 of 130 EVT patients (27%, 95% CI 20%-35%) (p = 0.572). Residual aneurysms at 1 year were less frequent with surgery (10/118 [8%, 95% CI 5%-15%]) than EVT (22/109 [20%, 95% CI 14%-29%]) (p = 0.015). Additional procedures (ventricular drainage and decompressive craniotomy, p < 0.05) and hospitalization > 20 days were more frequent in the surgery group (69/133 [52%, 95% CI 43%-60%]) than in the EVT group (38/130 [29%, 95% CI 22%-38%]) (p < 0.001).

Conclusions: This prematurely interrupted trial showed more frequent additional procedures and longer hospitalizations but better 1-year angiographic results with surgery. The primary clinical outcome, death or dependency at 1 year, was similar for EVT and surgery.