Evaluation and management of the lateral marginal vein in Klippel-Trénaunay and other PIK3CA-related overgrowth syndromes

J Vasc Surg Venous Lymphat Disord. 2020 May;8(3):482-493. doi: 10.1016/j.jvsv.2019.12.003. Epub 2020 Feb 20.


The lateral marginal vein is an anomalous clinical entity found in association with Klippel-Trénaunay and other PIK3CA-related overgrowth syndromes. Although it is reported to affect <20% of patients with Klippel-Trénaunay syndrome, this venous anomaly has been associated with significant morbidity and mortality attributable to venous hypertension and potentially lethal thromboembolic events. Limited literature exists on the diagnosis and management of this rare anomaly, with most of the reports focusing on retrospective clinical experience at a few centers of excellence. Despite these limitations, a systematic approach to diagnosis and treatment of this anomaly is warranted and expounded on herein. When plausible, clinical recommendations based on best available literature are made.

Keywords: Klippel-Trénaunay syndrome; Lateral marginal vein; PIK3CA-related overgrowth syndromes; Persistent embryonic vein.

Publication types

  • Review

MeSH terms

  • Ablation Techniques* / adverse effects
  • Class I Phosphatidylinositol 3-Kinases / genetics*
  • Embolization, Therapeutic* / adverse effects
  • Endovascular Procedures* / adverse effects
  • Genetic Predisposition to Disease
  • Humans
  • Klippel-Trenaunay-Weber Syndrome / diagnostic imaging
  • Klippel-Trenaunay-Weber Syndrome / genetics
  • Klippel-Trenaunay-Weber Syndrome / therapy*
  • Mutation*
  • Phenotype
  • Treatment Outcome
  • Veins / abnormalities
  • Veins / diagnostic imaging
  • Veins / surgery*
  • Venous Insufficiency / diagnostic imaging
  • Venous Insufficiency / genetics
  • Venous Insufficiency / therapy*


  • Class I Phosphatidylinositol 3-Kinases
  • PIK3CA protein, human