Intra-arterial dantrolene for refractory cerebral vasospasm after aneurysmal subarachnoid hemorrhage

Background Intravenous dantrolene has been used to prevent and treat cerebral vasospasm. We report a case of refractory cerebral vasospasm treated with intra-arterial dantrolene after aneurysmal subarachnoid hemorrhage. Methods A 56-year-old woman suffered a diffuse subarachnoid hemorrhage from a ruptured anterior communicating artery aneurysm which was successfully treated with coil embolization. She subsequently developed bilateral severe angiographic vasospasm which was treated with intraarterial vasodilators. However, owing to the recurrence of vasospasm, intra-arterial dantrolene followed by balloon angioplasty was used. Results There was moderate improvement of the severe vasospasm in bilateral A1 segments of the anterior cerebral arteries after microcatheter-based intra-arterial infusion of 30 ml (1 mg/ml) dantrolene. Patient's hemodynamic parameters were monitored during and after the procedure and no significant changes were seen after dantrolene infusion. A follow up cerebral angiogram after 1 day demonstrated the persistence of therapeutic effect. Conclusion Intra-arterial dantrolene induced a sustained improvement in cerebral vasospasm secondary to ruptured aneurysm. No significant side effects were observed during or after the infusion of the drug.