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Double Direct Injection of Blood into the Cisterna Magna as a Model of Subarachnoid Hemorrhage
Published on: August 30, 2020
Vasospasm after aneurysmal subarachnoid hemorrhage: need for further study
1Division of Neurosurgery and Keenan Research Centre, St. Michael's Hospital, Department of Surgery, University of Toronto, Toronto, Ontario, Canada.
Acta Neurochirurgica. Supplement
|December 11, 2008
Summary
Clazosentan effectively prevented cerebral vasospasm after subarachnoid hemorrhage (SAH). However, the phase 2b trial did not show improved patient outcomes, possibly due to study design limitations.
Area of Science:
- Neurology
- Neurosurgery
- Clinical Trials
Background:
- Cerebral vasospasm is a primary cause of poor outcomes after aneurysmal subarachnoid hemorrhage (SAH).
- Despite advances, patient outcomes following SAH remain suboptimal.
- Current treatments and management strategies have limitations in preventing delayed neurological deterioration.
Purpose of the Study:
- To evaluate the efficacy of clazosentan, an endothelin antagonist, in preventing cerebral vasospasm after aneurysmal SAH.
- To assess the impact of clazosentan on patient outcomes in the CONSCIOUS-1 trial.
- To inform the design of future clinical trials, such as CONSCIOUS-2, for optimizing SAH treatment.
Main Methods:
- A phase 2b clinical trial (CONSCIOUS-1) was conducted involving patients with aneurysmal SAH.
- Patients received clazosentan, and vasospasm was assessed angiographically.
- Patient outcomes were evaluated using modified Rankin and Glasgow outcome scales.
Main Results:
- Clazosentan demonstrated a dose-dependent reduction in angiographic vasospasm.
- The primary endpoint of improved patient outcome was not met in the CONSCIOUS-1 trial.
- Potential reasons for the lack of outcome improvement include study underpowering and alternative causes of neurological deterioration.
Conclusions:
- Clazosentan effectively prevents vasospasm in patients with aneurysmal SAH.
- Further research, like the phase 3 CONSCIOUS-2 trial, is needed to confirm the clinical benefit of vasospasm prevention on patient outcomes.
- Investigating alternative mechanisms of neurological injury post-SAH is crucial for improving patient prognosis.
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