Segmental arterial mediolysis

Cardiovasc Intervent Radiol. 2014 Jun;37(3):604-12. doi: 10.1007/s00270-014-0859-4. Epub 2014 Feb 20.

Abstract

Segmental arterial mediolysis (SAM) is an uncommon, nonatherosclerotic, noninflammatory, large- to medium-sized arteriopathy first described in 1976. It is characterized histologically by vacuolization and lysis of the outer arterial media leading to dissecting aneurysms and vessel rupture presenting clinically with self-limiting abdominal pain or catastrophic hemorrhages in the abdomen. Patients of all ages are affected with a greater incidence at the fifth and sixth decades. There is a slight male predominance. Imaging findings overlap with inflammatory vasculitis, collagen vascular disease, and fibromuscular dysplasia. The presence of segmental dissections involving the celiac, mesenteric, and/or renal arteries is the key distinguishing features of SAM. Inflammatory markers, genetic tests for collagen vascular disorders, and hypercoagulable studies are negative. Anti-inflammatory agents and immunosuppressants are not effective. A mortality rate of 50 % has been attributed to the acute presentation with aneurysmal rupture necessitating urgent surgical or endovascular treatments; in the absence of the acute presentation, SAM is a self-limiting disease and is treated conservatively. There are no established guidelines on medical therapy, although optimal control of blood pressure is considered the main cornerstone of medical therapy. The long-term prognosis is not known.

Publication types

  • Review

MeSH terms

  • Abdomen / blood supply*
  • Abdominal Pain / diagnosis
  • Aneurysm, Ruptured / diagnosis
  • Aneurysm, Ruptured / pathology
  • Aneurysm, Ruptured / therapy
  • Aortic Dissection / diagnosis
  • Aortic Dissection / pathology
  • Aortic Dissection / therapy
  • Arteries*
  • Diagnosis, Differential
  • Diagnostic Imaging*
  • Humans
  • Radiography, Interventional
  • Vascular Diseases / diagnosis*
  • Vascular Diseases / pathology
  • Vascular Diseases / therapy*