Abstract WMP26: Aneurysm Location and Its Relationship With Thrombotic and Hemorrhagic Complications During Flow Diversion Procedures: A Meta-Analysis

Abstract

Background and Purpose: Flow diversion with the Pipeline Embolization Device (PED; Medtronic, Minneapolis, MN) has become increasingly utilized in the treatment of otherwise difficult to manage wide-necked aneurysms. Variations in the propensity for hemorrhagic and thrombotic complications during these procedures has been attributed to differences in location as defined be an anterior circulation versus a posterior circulation location. This meta-analysis was conducted to assess and fully characterize the relationship between these aneurysm locations and thrombotic and hemorrhagic events. Materials and Methods: The currently available literature (2013 - 2018) was surveyed with PubMed and Google Scholar searches. Included studies were those for which aneurysm locations were accurately reported and for which intra and perioperative adverse events were noted. The data was subject to statistical analysis to assess the relationship between an anterior or posterior circulation location and thrombotic or hemorrhagic events. The collected data was subsequently statistically analyzed to assess for publication bias. Results: The searches yielded 49 studies, of which 34 met the inclusion criteria for this meta-analysis. The current meta-analysis assessed 4060 anterior circulation pipeline procedures for hemorrhagic complications, and 3100 for thrombotic complications. This study also assessed 608 posterior circulation pipeline procedures for hemorrhagic events, and 582 for thrombotic events. An anterior circulation location was associated with a 3% absolute risk of hemorrhagic events (CI: 0.02 - 0.04), and a 4% absolute risk of thrombotic events (CI: 0.04 - 0.05). A posterior circulation location was associated with a 6% absolute risk of hemorrhagic complications (CI: 0.04 - 0.08) and showed a greater 13% absolute risk of thrombotic events (CI: 0.10 - 0.16). Conclusions: A posterior circulation aneurysm location is associated with a higher propensity for both thrombotic and hemorrhagic events compared to an anterior circulation location. Thrombotic complications are almost twice as likely compared to hemorrhagic complications in the posterior location.