Diagnosis, Management and Outcomes in Children with Paget Schroetter Syndrome: A Retrospective Cohort Study

Abstract

Introduction Venous thoracic outlet syndrome occurs secondary to the extrinsic compression and impingement of the subclavian vein as it passes through the thoracic outlet, eventually resulting in upper extremity effort thrombosis, or Paget-Schroetter syndrome (PSS). This rare condition typically affects the dominant arm of athletic young adults with a history of repeated overhead activities. At Boston Children's Hospital (BCH), a multidisciplinary team of hematologists, interventional radiologists, and vascular surgeons manage these patients according to a standardized protocol including anticoagulation, pharmaco-mechanical thrombolysis, venoplasty, and decompressive rib-resection surgery. Herein we report the clinical and radiological outcomes of a cohort of patients with PSS managed at BCH. Objective The principle objective of this retrospective cohort study was to review the diagnosis, pharmacological, interventional radiology and surgical management, complications, and long-term outcomes of sequential pediatric patients (≤21 years) treated for PSS at BCH over a 3.5-year period of time (January 1, 2020 to July 31, 2023). Methods This study was performed as a part of an ongoing quality improvement initiative and was deemed exempt by the Institutional Review Board. Eligible patients were defined as children (≤21 years) with PSS per criteria established by the Society for Vascular Surgery. Clinical and demographic data, including post-thrombotic syndrome (PTS) scores of eligible patients were abstracted from their medical records. PTS evaluation at BCH is typically performed 6-12 months after DVT diagnosis using both the modified Villalta and Manco-Johnson instruments. Major bleeding, and recurrent/progressive thromboses were defined per published guidelines by the International Society on Thrombosis and Haemostasis. Standard statistical methods were used - median (range) for continuous variables and frequency with 95% CI for categorical data. Results The study cohort consisted of 20 patients (9 female). PSS was confirmed based on dynamic imaging with provocative maneuvers for all patients. Median (range) age at DVT diagnosis was 17 (15-21) years. Thirteen patients were diagnosed at an outside hospital and referred to BCH for further management. Fourteen patients received upfront anticoagulation with low molecular weight heparin of whom 13 patients were transitioned to a DOAC. Six patients were started on DOACs upfront. Fifteen subjects (75%) received upfront endovascular intervention at diagnosis. Median interval between DVT diagnoses to endovascular intervention was 5 (1-118) days. All patients underwent decompressive rib-resection surgery. Median interval between DVT diagnosis and surgery was 12 (7-39) weeks. Three patients (15%) developed major bleeding and 3 (15%) patients developed recurrent/progressive thrombosis after surgery. Two of the 3 patients who developed major bleeding were anticoagulated with a DOAC pre-operatively, which had been held for 48 hours before surgery. All subjects had a planned post-operative venogram, 14 (70%) of whom underwent completion venoplasty. Anticoagulation was discontinued in 18/20 (90%) patients with a median duration of therapy of 19.5 (14-60) weeks. Four patients (20%) were noted to have an underlying thrombophilia (Factor 5 R506Q [2]; Factor 2 G20210A [1]; Protein S deficiency [1]). End-of-therapy imaging was obtained for all patients - 17 (85%) had complete thrombus resolution, while two (10%) had partial thrombus resolution. Seventeen (85%) patients have undergone evaluation for PTS, of whom 12 (71%) were noted to have mild PTS and 2 (12%) have moderate-severe PTS as defined by the modified Villata instrument. Discussion Greater than 90% of pediatric patients with PSS who were treated per our institutional multi-disciplinary protocol had complete or partial thrombus resolution. Additionally, only 12% of patients reported moderate to severe PTS on follow-up and were prescribed sequential compression sleeves. Lastly, DOACs appear to be safe and efficacious in this cohort, though based on our internal data, we now interrupt DOACs for 72 hours before decompressive surgery.