title: Changes in plasma von Willebrand factor-cleaving protease (ADAMTS13) levels in patients with unstable angina.
abstract: BACKGROUND
  Increased plasma levels of von Willebrand factor (VWF) have been reported in acute myocardial infarction (AMI). Recently, we showed reduced activity of a VWF-cleaving protease (ADAMTS13) in AMI patients. However, there is no information as to whether ADAMTS13 affects the pathogenesis of unstable angina (UA). Thus, the purpose of this study was to examine changes in plasma VWF and ADAMTS13 levels in UA patients.
  
  
  METHODS
  Plasma VWF and ADAMTS13 levels (mU/ml) were measured in 45 patients with UA, 55 with stable exertional angina (SEA) and 47 with chest pain syndrome (CPS) at the time of coronary angiography. Levels were also measured in 15 UA patients after 6 months of follow-up.
  
  
  RESULTS
  VWF antigen levels (mU/ml) increased significantly in UA patients compared with SEA or CPS (2129.3+/-739.5, 1571.8+/-494.2 and 1569.5+/-487.0, respectively; P < 0.0001 in UA vs. SEA or CPS). ADAMTS13 antigen levels (mU/ml) were significantly lower in UA patients than SEA or CPS (737.3+/-149.5, 875.3+/-229.0 and 867.7+/-195.5, respectively; P < 0.01 in UA vs. SEA or CPS). Furthermore, there was a significant inverse correlation between VWF and ADAMTS13 antigen levels (r = -0.302, P = 0.0002). The antigen levels at 6 months of follow-up were not different compared to the acute phase in the 15 UA patients that had repeated blood sampling.
  
  
  CONCLUSIONS
  These findings suggest that there is prolonged thrombogenicity in UA patients represented as an imbalance between VWF and ADAMTS13 activity.
authors.affiliation: Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan.
authors.forename: Shunichiro
authors.initials: S
authors.lastname: Fuchigami
authors.forename: Koichi
authors.initials: K
authors.lastname: Kaikita
authors.forename: Kenji
authors.initials: K
authors.lastname: Soejima
authors.forename: Masakazu
authors.initials: M
authors.lastname: Matsukawa
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Honda
authors.forename: Kenichi
authors.initials: K
authors.lastname: Tsujita
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Nagayoshi
authors.forename: Sunao
authors.initials: S
authors.lastname: Kojima
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Nakagaki
authors.forename: Seigo
authors.initials: S
authors.lastname: Sugiyama
authors.forename: Hisao
authors.initials: H
authors.lastname: Ogawa
mesh_terms: D051722:ADAM Proteins / Q000097:blood*; D000071120:ADAMTS13 Protein; D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000787:Angina Pectoris / Q000097:blood / Q000201:enzymology; D000789:Angina, Unstable / Q000097:blood* / Q000201:enzymology*; D016022:Case-Control Studies; D002637:Chest Pain / Q000097:blood / Q000201:enzymology; D002908:Chronic Disease; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D013577:Syndrome; D014841:von Willebrand Factor / Q000378:metabolism*
chemical_list: D014841:von Willebrand Factor; D051722:ADAM Proteins; D000071120:ADAMTS13 Protein; C099604:ADAMTS13 protein, human