Management of radiological cerebral vasospasm after coil embolization for ruptured intracranial aneurysms: A noninferiority bicentric cohort study

Abstract: OBJECTIVE: Whether radiological cerebral vasospasm (CVS) should be proactively treated following subarachnoid hemorrhage to reduce the development of delayed cerebral ischemia (DCI) and brain infarction remains unclear. In this bicentric retrospective study, we sought to determine if a first-line intravenous therapy (IVT) to early detect and treat CVS could be noninferior on neurological outcomes to a first-line endovascular therapy (ET) requiring intra-arterial procedures for confirmed CVS as the reference approach. METHODS: Two cohorts of unselected patients exposed to the risk of CVS were studied following coil embolization for ruptured intracranial aneurysms. In the IVT group, CVS was actively detected and treated using a continuous intravenous infusion of milrinone for at least 7 days. In the ET group, selective intra-arterial infusions of nimodipine and milrinone were performed to treat confirmed CVS, and repeated if necessary. The primary endpoint was the proportion of patients with a good functional neurological outcome at 12 months using the modified Rankin Scale 0–2, with a noninferiority margin of 15%. RESULTS: The good outcome of patients exposed to the risk of CVS was noninferior between the IVT and ET strategies: 108/119 patients (91%; 95% confidence interval [CI] 84% to 95%) versus 77/97 patients (79%; 95% CI 70% to 87%), respectively. The IVT strategy led to the diagnosis of CVS in more patients in a shorter delay, and a reduced proportion of patients with DCI and brain infarction. There was no difference in the drug-related side effects between the two groups. CONCLUSION: A proactive intravenous treatment with milrinone to treat CVS had noninferior functional outcome compared to endovascular treatment using the selective intra-arterial infusion of vasodilator drugs.