Abstract 2165: Coronary Instent Restenosis of Drug-Eluting Stents is Associated with Serum Levels of MMP-9
BACKGROUND: Percutaneous coronary intervention (PCI) represents the most important treatment modality of coronary artery stenosis today. Although with the introduction of drug eluting stents (DES) in-stent restenosis (ISR) could be reduced dramatically, it still plays a significant role in the long-term outcome after PCI. This study aimed to evaluate if serum levels of matrix metalloproteinase-9 (MMP-9) are associated with the development of ISR after implantation of DES.
METHODS: We studied 85 patients. Blood samples were taken directly before and 24 hours after PCI with DES implantation. Serum levels of MMP-9 antigen and MMP-9 activity were measured by specific ELISA. Restenosis was evaluated at 6 to 8 months by coronary angiography.
RESULTS: During the follow up period, 2 patients (2.7%) died of cardiovascular causes and 12 patients (16 %) developed ISR. PCI significantly increased MMP-9 antigen and activity levels (p<0.0001). Patients with ISR at follow-up showed significantly higher MMP-9 activity levels at baseline (34Â±15 vs. 23Â±10 ng/mL; p<0.01) and 24 hours after PCI (56Â±30 vs. 29Â±15 ng/mL). Patients in the highest quartile before and after PCI showed a 7.5 (1.9–30) and 8.8 (2.1–37)-fold risk for the development of restenosis, respectively. This was independent of stent diameter, stent length, type of stent, number of stents, stented vessel as well as presence of diabetes.
CONCLUSION: The occurrence of ISR was significantly associated with MMP-9 activity before and after placement of DES. As MMP-9 may play a role in the pathogenesis of ISR, determination of MMP-9 serum levels might be helpful in the identification of patients with high risk for development of ISR after DES implantation.