Long-Term Recurrent Subarachnoid Hemorrhage After Adequate Coiling Versus Clipping of Ruptured Intracranial Aneurysms

Abstract

Coiling is increasingly used as treatment for intracranial aneurysms. Despite its favorable short-term outcome, concerns exist about long-term reopening and inherent risk of recurrent subarachnoid hemorrhage (SAH). We hypothesized a higher risk for recurrent SAH after adequate coiling compared with clipping. Patients with ruptured intracranial aneurysms coiled between 1994 and 2002 with adequate (>90%) aneurysm occlusion at 6-month follow-up angiograms were included. We interviewed these patients about new episodes of SAH. By survival analysis, we assessed the cumulative incidence of recurrent SAH after coiling and compared it with the incidence of recurrent SAH in a cohort of 748 patients with clipped aneurysms by calculating age and sex-adjusted hazard ratios. Of 283 coiled patients with a total follow-up of 1778 patient-years (mean, 6.3 years), one patient had a recurrent SAH (0.4%) and 2 patients had a possible recurrent SAH. For recurrent SAH within the first 8 years after treatment, the cumulative incidence was 0.4% (95% CI, -0.4 to 1.2) after coiling versus 2.6% (95% CI, 1.2 to 4.0) after clipping (hazard ratio, 0.2; 95% CI, 0.03 to 1.6). For possible and confirmed recurrent SAH combined, the cumulative incidence was 0.7% (95% CI, 0.3 to 1.7) after coiling versus 3.0% (95% CI, 1.3 to 4.6) after clipping (hazard ratio, 0.7; 95% CI, 0.2 to 2.3). Patients with adequately occluded aneurysms by coiling at short-term follow-up are at low risk for recurrent SAH in the long term. Within the first 8 years after treatment, the risk of recurrent SAH is not higher after adequate coiling than after clipping.