Rates of Delayed Rebleeding From Intracranial Aneurysms Are Low After Surgical and Endovascular Treatment

Abstract

Background and Purpose-Although results of the randomized International Subarachnoid Aneurysm Trial suggested that coil embolization was superior to surgical clipping 1 year after treatment, a paucity of data on long-term outcomes has been a major concern. Methods-In an ambidirectional cohort study, 9 institutions with expertise in intracranial aneurysm treatment identified all ruptured saccular aneurysms treated 1996 to 1998. After an initial medical record review, all patients meeting entry criteria were contacted by postal questionnaire or telephone. Possible reruptures were adjudicated independently by a neurologist, a neurosurgeon, and a neurointerventional radiologist. Rates of delayed (Ͼ1 year) and early rerupture and retreatment were evaluated using Kaplan-Meier survival analysis and the log-rank test. Results-A total of 1010 patients (711 surgically clipped, 299 treated with coil embolization) were included. Patients treated with coil embolization were older, more likely to have smaller aneurysms arising from the posterior circulation, and less likely to have middle cerebral artery aneurysms. Rerupture of the index aneurysm after 1 year occurred in 1 patient treated with coil embolization during 904 person-years of follow-up (annual rate 0.11%) and in no patients treated with surgical clipping during 2666 person-years (Pϭ0.11). Aneurysm retreatment after 1 year was more frequent in patients treated with coil embolization (PϽ0.0001), but major complications were rare during retreatment. Conclusions-Rerupture of aneurysms treated by either coil embolization or surgical clipping is rare after the first year.Late retreatment is more common after coil embolization than after clipping but complication rates are low. Thus, late events are unlikely to overwhelm differences between procedures at 1-year follow-up.

Intracranial Hemorrhage

“…There are currently at least two options for the acute treatment of a ruptured aneurysm: endovascular coiling or surgical clipping. Treatment of a recently ruptured aneurysm reduces the rate of rebleeding, and the benefit is related to the time to treatment initiation[162]. Current guidelines recommend that surgical clipping or endovascular coiling should be performed to reduce the rate of rebleeding after aneurysmal SAH, and these procedures should be performed early in the disease course.…”

Guidelines for the Management of Patients With Unruptured Intracranial Aneurysms

“…Despite the focus on RIAs, important information can be learned from the ISAT 8 and Cerebral Aneurysm Rerupture After Treatment (CARAT) 320 studies. Long-term follow-up data (mean, 9 years) on 2004 treated patients from the initial ISAT report reveal 24 rehemorrhages, 13 of which were from the treated aneurysm (10 treated by coiling and 3 by clipping).…”

Endovascular coil embolization of aneurysm neck for the treatment of ruptured intracranial aneurysm with bleb formation

“…Thus, endovascular embolization allows the elimination of the aneurysm with minimal interruption of blood supply to the brain. However, endovascular embolization presents a relatively high risk of aneurysm recurrence compared with the more invasive surgical closure, due to the fact that vascular endothelium may not be fully anastomosed at the aneurysm neck [24–26]. …”

“…Studies showed that an aneurismal SAH recurrence is 15–22 times more likely than the expected rate of a first SAH [34,35]. A study showed aneurysm recurrence in 8% of patients treated with coil embolization [26]. In a large series, 34% had an aneurysm recurrence in the 12 months following embolization [21].…”