title: Elevation of plasma matrix metalloproteinase-9 in the culprit coronary artery in patients with acute myocardial infarction: clinical evidence from distal protection.
abstract: BACKGROUND
  Although the elevation of circulating plasma matrix metalloproteinase (MMP)-9 levels in patients with acute myocardial infarction (AMI) has been documented, the origin of MMP-9 remains unclear.
  
  
  RESULTS
  Plasma MMP-9 levels in both the peripheral circulation and coronary arteries were measured in patients with AMI (n=23) and with stable angina pectoris (SAP, n=10) during percutaneous coronary intervention (PCI) with a distal protection device. Blood samples were collected from the femoral artery (FA) and the coronary artery before (Initial) and after (Second) dilation of the culprit lesion. Coronary sinus blood samples were obtained immediately after PCI (n=7). Coronary artery plaque fragments were aspirated in patients with AMI (n=20) and compared with those from patients with SAP who underwent directional atherectomy (n=10). MMP-9 levels in Initial and Second were significantly higher in patients with AMI than in patients with SAP (p<0.01). In AMI patients MMP-9 levels were significantly higher in Initial than in the FA (p<0.05), and were further increased in Second (p<0.0001), whereas those in the coronary sinus were similar to the FA. Immunohistochemistry revealed augmented MMP-9 expression in the coronary artery plaque fragments from AMI patients.
  
  
  CONCLUSIONS
  MMP-9 is mainly released into the coronary circulation from the coronary artery plaque in patients with AMI.
authors.affiliation: Kansai Rosai Hospital, Amagasaki, Division of Cardiovascular Medicine, Suita, Japan.
authors.forename: Shuichiro
authors.initials: S
authors.lastname: Higo
authors.forename: Masaaki
authors.initials: M
authors.lastname: Uematsu
authors.forename: Masakazu
authors.initials: M
authors.lastname: Yamagishi
authors.forename: Hatsue
authors.initials: H
authors.lastname: Ishibashi-Ueda
authors.forename: Masaki
authors.initials: M
authors.lastname: Awata
authors.forename: Takakazu
authors.initials: T
authors.lastname: Morozumi
authors.forename: Tomoki
authors.initials: T
authors.lastname: Ohara
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Nanto
authors.forename: Seiki
authors.initials: S
authors.lastname: Nagata
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D003326:Coronary Circulation; D003331:Coronary Vessels / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D006801:Humans; D020780:Matrix Metalloproteinase 9 / Q000097:blood*; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood* / Q000473:pathology / Q000601:surgery; D011237:Predictive Value of Tests
chemical_list: D015415:Biomarkers; D020780:Matrix Metalloproteinase 9