VPB0280 - Retrospective Case Series Study of patients with May-Thurner Syndrome in a single Tertiary Pediatric Center

Background: The 2018 ASH Pediatric Guidelines for Management of Venous Thromboembolism suggests against using thrombolysis in symptomatic deep venous thrombosis (DVT) patients (conditional recommendation).

Aims: Here we present a single center case series of 25 pediatric patients with May-Thurner Syndrome. Patients underwent thrombolysis followed by anticoagulation with little complications and no long-term significant post-thrombotic syndrome (PTS), challenging current guidelines. Current data using anticoagulation only demonstrates up to 80% PTS in this age group, suggesting alternative treatment regimens should be explored.

Methods: Deidentified data were extracted from outpatient records under institutional IRB exempt STUDY21050204, from the last 10 years. Thrombolysis consisted of institutional protocol using t-PA (0.03mg/kg/h), AngioJet (Boston Scientific) and unfractionated heparin infusion (10 u/kg/h). All patients received outpatient anticoagulation. Diagnosis of May-Thurner Syndrome was confirmed by venogram. Anticoagulation was started immediately after thrombolysis for 3 months followed by prophylaxis. PTS was assessed using modified Villalta Score (VS) and Manco-Johnson Instrument (MJI).

Results: Of 25 patients, 23 had analyzable data. Median age: 16 years old (80% females, 80% white). Presentation of symptoms to procedure: 4 days average. 78% with complete occlusion of, at least, one deep vein (Femoral, External Iliac, and Common Iliac). 46% of patients received a 2-day procedure and 81% received stent placement. Complications: 4 patients dropped ≥ 2g/dl hemoglobin, none required red cell transfusions, there were no bleeding in critical areas or compartment syndrome. Only 2 patients had readmissions for a second procedure due to recurrence of thrombosis. No patient scored moderate or higher in the VS nor Physically and Functionally Significant PTS in the MJI.

Conclusion(s): Thrombolysis in pediatric patients with May-Thurner Syndrome can be safe and effective, and may be considered in experienced pediatric tertiary centers. Further data is urgently needed to standardize care and avoid PTS is this young healthy population.