Abstract P414: Outcomes of Incident Hemorrhage From Cranial Dural Arteriovenous Fistulae: Analysis of the Multi-Center International Condor Registry

Abstract

Introduction: Dural artertiovenous fistulae (dAVF) are rare causes of secondary intracranial hemorrhage (ICH) and there remains a paucity of knowledge regarding their natural history. To date our knowledge comes from small case series. CONDOR, (Consortium for Dural Arteriovenous Fistula Outcomes Research), a large multi-institutional retrospective registry, provides a unique opportunity to evaluate the outcomes of patients presenting with dAVF related hemorrhages. Methods: We performed a retrospective review of 1077 dAVF patients from the CONDOR registry and selected those patients who presented with hemorrhage secondary to the dAVF. Patient characteristics, clinical presentation/follow-up, and radiographic details were analyzed for associations with patient outcomes. An outcome of mRS 0-2 was categorized as a “good” outcome and 3-6 as “poor”. Statistics were performed in SAS 9.4 with chi square, fisher’s exact test, and stepwise select variable multivariate analysis; P<.05 was marked as the level for statistical significance. Results: Evaluation of the CONDOR dataset yielded 267 patients who presented with hemorrhage. The mean age of the population was 59 ±13y.o, 30% were female, 40% had a history of smoking and 93% were not on anticoagulants. The median follow-up was 1.4 years. The mortality was 4.0 % at follow-up, and 83% of patients had a good outcome (mRS 0-2). Univariate analysis found age (p=0.001), anticoagulant use (p=0.006), and presentation mRS (p=0.03) were associated with poor outcome at follow-up. Subtype of hemorrhage (parenchymal hemorrhage or subarachnoid hemorrhage), smoking, and cortical venous shunting of the lesion, (i.e. Cognard grade IIb and greater) did not reach statistical significance. On multivariate analysis age (p=0.023) and mRS (p=0.035) at presentation but not anti-coagulant use (p=0.11) was associated with follow-up mRS. Conclusion: Within the largest individual patient series to date, we found that dAVF presenting with hemorrhage was associated with a relatively low risk of mortality. Age and mRS at presentation were most strongly predictive of outcome. Our results suggest that dAVF hemorrhage may be associated with a less morbid outcome than other forms of secondary hemorrhage.