title: Thyroid hormone levels in patients with aortic dissection: comparison with controls and correlation with the percentage of the aortic media composed of myxoid deposits.
abstract: OBJECTIVE
  Deposits of myxoid material, similar to myxedema related to thyroid disease, are described in the medial layer of aortas with dissection. We analyzed the clinical or subclinical thyroid dysfunction of patients with this disease and analyzed whether a correlation exists between serum levels of thyroid-related hormones and the myxoid content of the aortic media.
  
  
  METHODS
  We measured, with standard methods, serum levels of triiodothyronine (T3), thyroxine (T4), and thyroid stimulating hormone (TSH) in 28 patients who underwent aortic dissection and free T4 in 20 of them. The same hormones were quantified in 20 control patients matched by sex and age. Results were compared by using the Mann-Whitney test. We also measured the percentage of the aortic media occupied by myxoid material in the surgical specimens of 25 of the patients with aortic dissection and analyzed its correlation with hormone levels by using the Pearson test.
  
  
  RESULTS
  In the 20 pairs in which the amount of hormones was compared, the mean values for T3, T4, free T4, and TSH were 1.22ng/mL, 9.89mcg/dL, 1.18ng/dL, and 5.45 microIU/mL in study patients and 1.15ng/mL, 8.57mcg/dL, 1.32ng/dL, and 2.15 microIU/mL in controls. Neither these differences nor the correlation between the percentage of myxoid content (mean=30%) and the values for T3, T4, free T4, and TSH (mean 1.22ng/mL, 9.44mcg/dL, 1.20ng/dL, and 5.08 microIU/mL, respectively; n= 25) were significant.
  
  
  CONCLUSIONS
  Our data suggest that serum levels of thyroid hormones have no relation with the myxoid content in the aortic media in cases of aortic dissection.
authors.affiliation: Instituto do Coração, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil. anppaulo@incor.usp.br
authors.forename: Paulo Sampaio
authors.initials: PS
authors.lastname: Gutierrez
authors.forename: Maria Adelaide Albergaria
authors.initials: MA
authors.lastname: Pereira
authors.forename: Regina Célia Martins
authors.initials: RC
authors.lastname: Oliveira
authors.forename: Noedir Antonio Groppo
authors.initials: NA
authors.lastname: Stolf
authors.forename: Maria de Lourdes
authors.initials: Mde L
authors.lastname: Higuchi
mesh_terms: D000328:Adult; D000368:Aged; D000784:Aortic Dissection / Q000097:blood* / Q000473:pathology; D001014:Aortic Aneurysm / Q000097:blood* / Q000473:pathology; D016022:Case-Control Studies; D004730:Endothelium, Vascular / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013963:Thyroid Hormones / Q000097:blood*
chemical_list: D013963:Thyroid Hormones