Abstract TP587: Microsurgery Treatment Rate for Unruptured Cerebral Arteriovenous Malformations is Increased post-ARUBA

Abstract

Background: The ARUBA trial reported medical management was superior to intervention for unruptured cerebral arteriovenous malformations (cAVMs); however, open excision was underrepresented in the intervention arm. We investigated whether the ARUBA trial results influenced treatment modality rates for unruptured cAVMs within the United States. Methods: We queried the National Inpatient Sample (NIS), the largest all-payer inpatient care database in the United States, and identified 2,028 patients that underwent treatment for unruptured cAVMs between January 2011 and September 2015. All screened subjects had AVM ICD-9-CM diagnosis code 747.81 (anomalies of cerebrovascular system) and were excluded based on hemorrhage codes 430 (SAH) and/or 431 (ICH). ICD-9-CM principal procedure codes were used to identify treatment modalities: endovascular (39.72), open excision (01.59), and stereotactic radiosurgery (SRS) (92.30-.39). Univariate logistic regression was used to compare treatment rates for each modality before and after two ARUBA time points: 1) European Stroke Conference (ESC) presentation May 2013 and 2) The Lancet publication February 2014. Results: When unruptured cAVMs were treated, the rate of open excision was greater after, compared to before, the May 2013 ARUBA presentation (OR 1.22, p<0.05). Additionally, a trend for open excision was noted using the February 2014 publication date (OR 1.20, p=0.054). Endovascular and SRS did not show significant differences in treatment rates at either time point. Conclusions: Unruptured cAVMs within the NIS database that underwent treatment had open excision significantly more after, compared to before, the ARUBA results were presented at the ESC. When using The Lancet publication date, a non-significant trend for open excision was noted but likely resulted from insufficient numbers in the post-Lancet publication group. Our findings suggest that the ARUBA trial has influenced current treatment modality rates for unruptured cAVMs captured within the NIS.