Background and Purpose: Brain arteriovenous malformations (BAVMs) are a leading cause of intracranial hemorrhage in young adults. Contrary to subarachnoid hemorrhage, there is no validated scale dedicated to stratifying patients with BAVM rupture. We aimed to design a new BAVM prognostic score.
Methods: Records of 135 patients with 139 BAVM rupture events consecutively admitted to a tertiary care center during 11 years were reviewed. Independent predictors of long-term poor outcome (modified Rankin scale (mRS) > 3) more than one year after admission were identified. A risk stratification scale was developed and compared to the intracerebral hemorrhage (ICH) score to predict poor outcome and delta mRS (difference between follow-up and baseline pre-hemorrhage mRS).
Results: Multivariate logistic regression followed by stepwise analysis determined that consciousness level (odd ratio [OR] 6.5, 95% confidence interval (CI) [3.09-13.7], P < 10-3), hematoma volume (OR 1.84, 95% CI [1.21-2.8], P = 0.005) and intraventricular hemorrhage (OR 7.46, 95% CI [2.66-21], P-value < 10-3) were independently associated with 1-year poor outcome. A 12-scale simplified score for ruptured BAVM prognostication was constructed combining consciousness level, hematoma volume and intraventricular hemorrhage . This new score was a stronger predictor of poor outcome (P=0.009) and delta mRS 3 (P=0.01) than ICH score.
Conclusion: We propose a new admission score (the Ruptured AVM Prognostic Score [RAPS]) dedicated to stratifying the risk of poor long-term outcome after BAVM rupture. This easy to use score may serve both to improve communication between healthcare providers and consistency in clinical research.