Open Resection for Unruptured Cranial Arteriovenous Malformations (AVMs) after the ARUBA Trial: A National Surgical Quality Improvement Program (NSQIP) Study

Introduction: In 2014, A Randomized Trial of Unruptured Brain Arteriovenous Malformations (ARUBA) concluded that medical management alone for cranial arteriovenous malformations (AVMs) had better clinical outcomes than interventional treatment. A significant decrease in the rate of open AVM resection was seen later in practice compared to endovascular treatment. ARUBA's impact on interventional changes and outcome rates is still unknown. Thus, we investigated whether the conclusions from ARUBA may have influenced the outcomes following the open resection of unruptured AVMs.

Methods: The National Surgical Quality Improvement Program was queried between 2010 and 2020 for patients who underwent open resection of unruptured AVMs. Logistic regression was used to assess the odds of postoperative rupture, upper quartile of length of stay(Q3-LOS ≥12 days),and operative time(Q3-OT ≥327 minutes)following open resection of AVMs. Join-point regression was used to assess differences in outcomes following resection before and after ARUBA.

Results: A total of 760 patients underwent open resection of AVMs, with 152 having ruptured lesions. The postoperative Q3-LOS, Q3-OT, and postoperative AVM rupture rates decreased between 2010 and 2020(p < 0.01). Comparing pre and post-ARUBA timelines, we found that the pre-ARUBA period(OR= 1.71,p=0.03) and transfer from non-home(OR= 2.79,p < 0.01) were more likely to increase the risk of AVM rupture following resection. Age(OR= 1.03,p < 0.01),higher preoperative WBC(OR= 1.1,p < 0.01), and platelet count(OR= 1.003,p=0.02) were more likely to increase the risk of Q3-LOS following resection while smoking is more likely to increase the risk of Q3-OT(OR= 1.49,p < 0.01). During the post-ARUBA period, preoperative INR(OR= 15.64,p < 0.01) and independent functional status(OR= 5.31,p < 0.01) were more likely to increase the risk of postoperative AVM rupture; Age(OR= 1.03,p=0.01) and emergency surgery(OR= 3.35,p=0.01) were more likely to increase the Q3-LOS.

Conclusion : The duration of Q3-LOS,Q3-OT and rate of AVM rupture following open resection decreased post-ARUBA,suggesting that ARUBA may have influenced the open surgical practices for unruptured AVM.