Elevation of plasma matrix metalloproteinase-9 in the culprit coronary artery in patients with acute myocardial infarction: clinical evidence from distal protection.
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.
Higo
Shuichiro
S
Kansai Rosai Hospital, Amagasaki, Division of Cardiovascular Medicine, Suita, Japan.
Uematsu
Masaaki
M
Yamagishi
Masakazu
M
Ishibashi-Ueda
Hatsue
H
Awata
Masaki
M
Morozumi
Takakazu
T
Ohara
Tomoki
T
Nanto
Shinsuke
S
Nagata
Seiki
S
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
D015415:Biomarkers; D020780:Matrix Metalloproteinase 9