The long‐term prognosis in untreated cerebral aneurysms: I. The incidence of late hemorrhage in cerebral aneurysm: A 10‐year evaluation of 364 patients

Abstract

Three hundred sixty-four patients who suffered a subarachnoid hemorrhage from an aneurysm in either the posterior communicating or anterior communicating artery and who were not surgically treated have been followed for up to 21 years in order to determine the frequency of subsequent hemorrhage. For patients surviving six months: (1) rebleeding occurs on the average of 3.5% per year during the first decade; (2) the mortality associated with a late rebleed is 67%; (3) high blood pressure and female sex predispose to late rebleeding in posterior communicating artery aneurysms; (4) young patients take longer to rebleed than older patients but do so at the same rate; and (5) increase in aneurysm size as judged by routine arteriography six months after the initial hemorrhage did not correlate with rebleeding, although an increase in size had occurred in all patients who were studied angiographically at the time of their late rebleed.

Risk of Hemorrhage in Combined Neuroform Stenting and Coil Embolization of Acutely Ruptured Intracranial Aneurysms

“…Only one other study treated all aneurysms within 48 hours 22 . It is reasonable to expect a higher procedural rupture rate when treating early (98% of our patients treated within 24 hours) as the incidence of re-rupture during the first 24 hours is 4%, with the maximal risk during the first six hours [25][26][27] . As cerebral angiography is a known risk factor for SAH, our early treatment paradigm may also explain the two cases of rebleeding during the diagnostic arteriogram which occurred before intracranial access or anticoagulation.…”

Imaging of cerebral aneurysms: a clinical perspective

“…Aneurysms that have already ruptured have a much higher risk of re-hemorrhage [5,6]. Additionally, the angiomorphology of the aneurysm has also been posited to influence future hemorrhage risk factors, such as irregular domes [7,8], daughter sacs [9], and low wall shear stress [10].…”

Could late rebleeding overturn the superiority of cranial aneurysm coil embolization over clip ligation seen in the International Subarachnoid Aneurysm Trial?

“…22 Beyond 1 year, natural history data suggest a constant rebleeding rate. 33 Rebleeding Ͼ 1 year after treatment (referred to as "late rebleeds") observed in the ISAT were rare, 14 so the confidence limits that can be placed on rebleeding rates are quite wide. The rebleeding rate so far in those randomized to coil embolization is 0.21% per patient year, based on 7 hemorrhages, 13,14 and in those randomized to clip ligation it is 0.063% per patient year based on 2 rebleeding episodes, although 1 of these patients received coil embolization rather than clip placement, and in the other the aneurysm was treated with clips.…”