Ruptured intracranial aneurysms are associated with a high risk of permanent neurological impairment or death. Evidence suggests that detachable coils can be used to treat ruptured aneurysms safely and effectively; however, data regarding their long-term efficacy is sparse.OBJECTIVE
To determine the frequency of late rebleeding of ruptured intracranial aneurysms after treatment with detachable coils.DESIGN AND INTERVENTION
In this retrospective study that was conducted over 8 years, 393 consecutive patients (70% female, 30% male) with a ruptured aneurysm were treated with a detachable coil and followed up to determine the incidence of late rebleeding-defined as recurrent hemorrhage from a coiled aneurysm >1 month after coiling. Using angiography, treatment outcomes were classified as complete occlusion (98-100%), near-complete occlusion (90-98%) or incomplete occlusion (<90%). Patients were followed up clinically 6 weeks after initial discharge, and underwent angiographic follow-up at 6 months and 18 months. Further appropriate treatment was undertaken if incomplete occlusion was discovered at any time during the follow-up period. At the time of initial coiling, the mean patient age was 52.9 years (range 25-81 years). In total, 63% of patients were classified as Hunt and Hess (HH) Stroke Scale I-II, 21% were HH III and 16% were HH IV-V. The majority of treated ruptured aneurysms were located in the anterior communicating artery (n = 123), the basilar tip (n = 85) or the posterior communicating artery (n = 68).OUTCOME MEASURES
The primary outcome was the number of patients to experience late rebleeding after coiling of a ruptured aneurysm. A secondary outcome was the number of patients to require follow-up treatment for aneurysms.RESULTS
Clinical data was available for 392 of the 393 patients. The total follow-up duration was 18,708 months, or 1,559 patient-years (mean 47.7 months, range 0-120 months). During follow-up, 70 patients (17.8%) died; deaths were attributed to various factors including subarachnoid hemorrhage (n = 23), unrelated causes (n = 21) and procedural complications of coiling (n = 11). Mortality associated with late rebleeding was 0.76% (n = 3), giving an annual late-rebleeding mortality rate of 0.19% (95% CI 0.04-0.60%). The late-rebleeding incidence was 1.27% (n = 5), giving an annual late-rebleed rate of 0.32% (95% CI 0.12-0.78%). The median size of the original aneurysm in patients with late rebleeding was 17 mm, compared with 8 mm in patients without late rebleeding (P = 0.0017). Late rebleeding occurred in 3 of 366 (0.82%) patients with complete initial aneurysm occlusion, and 2 of 27 patients (7.41%) with incomplete initial occlusion (P = 0.04). Additional treatment was required for 53 (13%) coiled aneurysms during the follow-up period. There was no significant difference in the median ages and gender ratios between patients who experienced late rebleeding and those who did not.CONCLUSION
Coiling of ruptured aneurysms is associated with a very low rate of rebleeding. Angiographic follow-up reveals incomplete initial occluded aneurysms that might require additional treatment.