Abstract 097: Endovascular Treatment of Refractory Vasospasm in Aneurysmal Subarachnoid Hemorrhage: A Single Center 16‐year Experience

Introduction Refractory post‐hemorrhagic cerebral vasospasm (PHCV) in patients with aneurysmal subarachnoid hemorrhage (aSAH) is a morbid and possibly fatal condition that often requires endovascular treatment with either intra‐arterial (IA) vasodilator therapy or percutaneous transluminal balloon angioplasty (PTA). This study aims to evaluate the efficacy of these treatments and explore the risk factors of poor clinical outcomes amongst patients with refractory PHCV receiving endovascular therapy. Methods All adult patients who received IA vasodilators or PTA for PHCV due to aSAH from 2007 to 2023 at our institution were included. Patients were divided into Good and Poor outcome cohorts based on 6‐month modified Rankin of > 2 cutoff and were compared for all identifiable risk factors using multivariate analysis. Radiographic changes in vessel diameter and cerebral circulation time (CCT) were measured and compared between individual PTA and IA sessions using various metrics. Results A total of 83 refractory vasospasm patients with an average age of 52.0 years old, 66% of whom were female. Poor outcomes were seen in 65% of patients. Female sex (p=0.045) and initial vasospasm symptom of only headaches (p=0.044) were protective factors against poor outcomes. History of hypertension (p=0.010), earlier onset of vasospasm (p=0.008), requiring systemic hypertensive therapy (p=0.012), and longer initial pre‐treatment CCT (p=0.042) were risk factors of poor outcomes. PTA was superior to IA vasodilators pre‐ to post‐treatment vessel diameter (0.44 mm in PTA compared to 0.23 mm in IA; p=0.017) but CCT was similarly improved with both modalities. Conclusions In this single‐center retrospective review, most patients (65%) treated with endovascular therapy for PHCV experienced poor outcomes. A history of hypertension, earlier onset of vasospasm, and longer initial pre‐treatment CCT were predictive of poor outcome. Female sex and headache presentation were predictive of good outcomes. PTA had a statistically superior intra‐treatment improvement in vessel diameter compared to IA vasodilators. All other radiographic parameters were similar between PTA and IA therapy.