NCT01668563

International Subarachnoid Aneurysm Trial II

International Subarachnoid Aneurysm Trial II Comparing Clinical Outcomes of Surgical Clipping and Endovascular Coiling for Ruptured Intracranial Aneurysms Not Included in the Original ISAT Study.

• Status: Active Not Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 1,724 (estimated)
• Sponsor: Centre hospitalier de l'Université de Montréal (CHUM) · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

The purpose of this study is to compare the clinical outcome of surgical clipping and endovascular coiling for ruptured intracranial aneurysms not included in the original ISAT Study.

Detailed description

The International Subarachnoid Aneurysm Trial (ISAT) was a turning point in modern neurosurgical history (1). The trial showed that for 2143 subarachnoid hemorrhage (SAH)patients eligible for both surgery and endovascular coiling, randomized allocation to coiling was associated with better one year clinical outcomes, defined as survival without dependency (absolute risk reduction (ARR) of 7.4% (95%CI; 3.6 - 11.2, p=0.0001). Because ISAT was a positive pragmatic trial, the interpretation of the trial results was that coiling should be adopted as the first-line treatment for ruptured lesions, for patients with the types of aneurysms included in ISAT, of which the great majority were small (≥10 mm) anterior circulation aneurysms. Although ISAT was well-designed, conducted, and reported, trial results were not always properly interpreted, and endovascular coiling was perhaps inappropriately extrapolated beyond what ISAT demonstrated. Endovascular treatment for ruptured aneurysms has now become first-line treatment in many centers (2), which may be appropriate for small, anterior circulation lesions, but there is no evidence to support this practice for the wide spectrum of non-ISAT patients and aneurysms. A recent pre-randomized study of coiling as first-intention (3)showed better results for those ruptured aneurysms felt to be readily coilable; however, the optimal management of more difficult-to-coil ruptured aneurysms remains unclear. Further compounding the problem are the concerns that aneurysm coiling may not be as durable in the long-term as surgical clipping, leading many neurosurgeons to continue to clip most ruptured aneurysms in spite of ISAT results. Proponents of endovascular treatment sometimes justify this extrapolation of ISAT results on the basis of improved catheter and coil technology, although this has never been demonstrated. However, the addition of stents and flow-diverters, which were not tested in ISAT, may increase endovascular treatment risks, especially when combined with dual anti-platelet agents. The introduction of these devices allowed for the expansion of indications of EVT to include wide-necked aneurysms, lesions which would not have been included in ISAT. The wider spectrum of patients and aneurysms now considered for EVT may not all experience the same degree of benefit as seen in the original ISAT trial (4). Considering the relatively small ARR of 7.4% favouring coiling, when the additional risks due to stents are included, the balance may have tipped to favour surgical clipping. These new questions deserve formal study in the context of a randomized clinical trial.

Conditions

• Intracranial Hemorrhage Ruptured Aneurysm

Interventions

Type	Name	Description
PROCEDURE	surgical management	Surgical clipping will be performed as soon as possible following randomization, according to standards of practice, and under general anesthesia. Aneurysms thought by the treating physicians to require deliberate permanent proximal vessel occlusion, construction of a surgical bypass, or other flow-redirecting treatments that do not directly clip the aneurysm will not be excluded; these non-ISAT aneurysms are expected to be more difficult lesions to manage surgically as well as endovascularly.
PROCEDURE	Endovascular management	Endovascular treatment will also be performed as soon as possible following randomization,according to standards of practice, and under general anesthesia. Details regarding type of coils, use of adjunctive techniques such as balloon-remodeling, stents or flow-diverters, as well as post-treatment medical management issues, will be left up to the physician performing the endovascular treatment.

Timeline

• Start date: 2012-11-12
• Primary completion: 2024-12-01
• Completion: 2024-12-01
• First posted: 2012-08-20
• Last updated: 2024-08-15

Locations

6 sites across 3 countries: United States, Canada, Spain