Subclavian Artery Thrombosis Workup

Updated: Aug 12, 2021
  • Author: Mary C Mancini, MD, PhD, MMM; Chief Editor: John Geibel, MD, MSc, DSc, AGAF  more...
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Laboratory Studies

Laboratory studies that may be useful include the following:

  • Complete blood count (CBC), platelet count, and basic chemistry profile - Results should be within reference ranges; however, abnormalities in these parameters could be early indicators of dehydration or a hypercoagulable state
  • Prothrombin time (PT) and activated partial thromboplastin time (aPTT) - Again, results should be within reference ranges; however, they should be checked in order to assess the patient's coagulation profile
  • Antithrombin III level - In a hypercoagulable state, the antithrombin III level is low
  • Alpha-macroglobulin and plasminogen levels - Low levels indicate a prothrombotic state
  • Fibrinogen, factor VII, and factor VIII levels - Elevated levels indicate a prothrombotic state
  • Protein C and S levels - Abnormalities in these parameters indicate a chronic inflammatory state
  • Factor V Leiden and factor II C20210-a levels

Imaging Studies

Arteriography is a vital component of the evaluation process with regard to determining the anatomic aberrations of the arterial system and planning possible therapeutic interventions. A venous runoff should be included as well, because accompanying subclavian vein pathology should not be overlooked.

Computed tomography (CT) can help define bony pathology of the thoracic outlet that may contribute to occlusion of the subclavian artery. In particular, multidectector CT (MDCT) may be useful. [9]

Magnetic resonance arteriography (MRA) is a useful modality for defining subclavian artery anatomy and pathology. [10]

Echocardiography should be obtained in order to evaluate possible sources of arterial emboli.