title: Etiology of peripheral arterial thromboembolism in young patients.
abstract: BACKGROUND
  No prior studies have explored the etiology of peripheral arterial thromboembolic events (PATE) in younger patients. Therefore, we analyzed the sources of these events in patients <50 years of age over a recent 10-year period. Diagnostic and work-up strategies will be proposed based on the presence of cardiac or atherosclerotic risk factors.
  
  
  METHODS
  The sources of emboli were classified as (1) conventional (cardiac or arterioarterial), (2) unconventional, or (3) unknown. A statistical analysis of risk factors that, if absent, would suggest an unconventional cause was performed. Risk factors included those for cardiac and atherosclerotic disease: coronary artery disease (CAD), valvular disease, smoking, arrhythmia, hypertension, or diabetes mellitus.
  
  
  RESULTS
  Overall, 51 patients were identified. Twenty-nine patients (57%) had unconventional causes (8 paradoxical emboli, 4 possible paradoxical emboli, 12 hypercoagulable states, 3 white clot syndromes, and 2 cervical ribs), 17 (33%) had conventional causes, and 5 (10%) were unknown. When the number of cardiac risk factors was < or =1, excluding smoking, the probability of a conventional source was zero, in contrast to 100% if the number of risk factors was >1. When the following risk factors were absent, there were significantly more unconventional than conventional sources of emboli (P < 0.001): smoking (100% versus 0%), CAD (93% versus 7%), arrhythmias (83% versus 17%), hypertension (93% versus 7%), and diabetes mellitus (81% versus 19%). Patients with a conventional source were significantly older (44 versus 38 years).
  
  
  CONCLUSIONS
  The "unconventional" causes of PATE were responsible for a higher percentage of cases in young patients. An analysis of the number of risk factors was useful in predicting which patients suffered embolic events from conventional sources, with the critical number being >1 (excluding smoking). Therefore, when younger patients present with PATE, and are found to have < or =1 identifiable cardiac risk factor, their work-up should be directed toward the unconventional sources first.
authors.affiliation: Department of Surgery, Robert C. Byrd Health Sciences Center of West Virginia University, Charleston Area Medical Center, USA.
authors.forename: A F
authors.initials: AF
authors.lastname: AbuRahma
authors.forename: B K
authors.initials: BK
authors.lastname: Richmond
authors.forename: P A
authors.initials: PA
authors.lastname: Robinson
mesh_terms: D000328:Adult; D000367:Age Factors; D000792:Angiography; D001145:Arrhythmias, Cardiac / Q000150:complications; D003327:Coronary Disease / Q000150:complications; D048909:Diabetes Complications; D017548:Echocardiography, Transesophageal; D019320:Embolism, Paradoxical / Q000209:etiology; D005260:Female; D006349:Heart Valve Diseases / Q000150:complications; D006801:Humans; D006949:Hyperlipidemias / Q000150:complications; D006973:Hypertension / Q000150:complications; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects; D013923:Thromboembolism / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000209:etiology*