Abstract WP431: Distinguishing RCVS-associated Subarachnoid Hemorrhage From Cryptogenic and Aneurysmal Subarachnoid Hemorrhage

Abstract

Background: Reversible cerebral vasoconstriction syndrome (RCVS) is a self-limited entity with usually benign outcome. Over 30% RCVS patients develop subarachnoid hemorrhage (SAH). We aimed to identify features that differentiate RCVS-SAH from more ominous causes of SAH, i.e. aneurysmal SAH (aSAH) and cryptogenic ‘angio-negative’ SAH (cSAH). Methods: We compared the clinical-imaging features of 38 consecutive RCVS-SAH patients, to 515 aSAH and 93 cSAH patients consecutively admitted to Massachusetts General Hospital. Results: As compared to aSAH and cSAH, the RCVS-SAH group was significantly younger, more women, and higher frequency of migraine, depression, chronic obstructive pulmonary disease (COPD), alcohol and drug exposure, and prior antidepressant use. The distribution of Hunt-Hess (HH) grade and Fisher group were different between groups, with median values highest in the aSAH group. The RCVS-SAH group had more hypodense lesions on 1st head CT and earlier, more severe and widespread vasoconstriction on cerebral angiography. Discharge mRS scores were lowest in the RCVS-SAH group. To avoid overfitting, multivariate logistic regression (Firth’s method) was performed using separate models for clinical and radiological variables given small "N". Predictors of RCVS-SAH vs. aSAH [model 1]: age (O.R. 0.9, 95% C.I. 0.9-0.96), prior headache disorder (O.R. 9.3, 95% C.I. 3.9-22.4), depression (O.R. 5.6, 95% C.I. 1.8-17.6), and COPD (O.R. 7.6, 95% C.I. 2.9-20.1), and [model 2]: HH grade (O.R. 0.4, 95% C.I. 0.2-0.7), Fisher group (O.R. 0.2, 95% C.I. 0.07-0.4), and the number of constricted arteries (O.R. 1.6, 95% C.I. 1.4-1.9). Predictors of RCVS-SAH vs. cSAH [model 1]: age (O.R. 0.9, 95%C.I. 0.9-0.97), prior headache (O.R. 10.3, 95% C.I. 4.3-24.9), depression (O.R. 6.9, 95% C.I. 2.1-22.4), and alcohol use (O.R. 5.1, 95% C.I. 2.0-12.9), and [model 2]: Fisher group (O.R. 0.01, 95% C.I. 0.0-0.6), vasospasm severity (O.R. 9.1, 95% C.I. 1.4-57.2), and the number of constricted arteries (O.R. 2.0, 95% C.I. 1.2-3.1). Conclusion: Several clinical-imaging features distinguish RCVS-SAH from aSAH and cSAH. These data should prove useful to improve the diagnostic accuracy, management, and resource utilization in patients with SAH.