Editor's Choice - Management of Lower Extremity Venous Outflow Obstruction: Results of an International Delphi Consensus

Objective: The endovascular treatment of venous obstruction has expanded significantly in recent years. Best practices for optimal patient outcomes are not well established and the evidence base is poor. The purpose of this study was to obtain consensus on management criteria for patients with lower extremity venous outflow obstruction. Methods: The study was conducted as a two round Delphi consensus. Statements addressed imaging, symptoms and other baseline measures, differential diagnosis, treatment algorithm, indications for stenting, inflow and outflow assessment, successful procedural outcomes, post -procedure therapies and stent surveillance, and clinical success factors. Statements were prepared by six expert physicians (round 1, 40 statements) and an expanded panel of 24 physicians (round 2, 80 statements) and sent to a pre-identified group of venous experts who met qualifying criteria. A 9 point Likert scale was used and consensus was defined as > 70% of respondents rating a statement between 7 and 9 (agreement) or between 1 and 3 (disagreement). Round 1 results were used to guide rewording and splitting compound statements for greater clarity in round 2. Results: In round 1, 75 of 110 (68%) experts responded, and 91 of 121 (75%) experts responded in round 2. Round 1 achieved consensus in 32/40 (80%) statements. Consensus was not reached in the treatment algorithm section. Round 2 achieved consensus in 50/80 (62.5%). Statements reaching consensus were imaging (2/3, 66%), symptoms and other baseline measures (12/24, 50%), differential diagnosis (2/8, 25%), treatment algorithm (10/17, 59%), indications for stenting (10/10, 100%), inflow and outflow assessment (2/2, 100%), procedural outcomes (2/2, 100%), post -procedure therapies and stent surveillance, (5/7, 71%), and clinical success factors (5/7, 71%). Conclusion: This study demonstrated that considerable consensus was achieved between venous experts on the optimal management of lower extremity venous outflow obstruction. There were multiple domains where consensus is lacking, highlighting important areas for further investigation and research.