Abstract 3132: High Soluble Fas Plasma Levels Are Protective After Stent Implantation
BACKGROUND: Percutaneous coronary intervention (PCI) represents the most important treatment modality of coronary artery stenosis today. But instent restenosis (ISR) is still a limitation for the long-term outcome. sFas as a member of the TNF-Alpha receptor superfamily mediates apoptosis and the Fas/FasL system is also essential for the inhibition of vessel wall inflammation. Until now only little is known about the role of apoptosis in the context of vascular repair after injury.
METHODS: To dermine wether sFas induced apoptosis is predictive for ISR, we studied 138 patients with stable coronary artery disease who underwent elective and successful PCIs (BMS=24; DES=114). Blood samples were taken directly before and 24 hours after PCI and sFas plasma levels were measured with specific Elisa. Restenosis was evaluated six months later either by coronary angiography or by exercise testing.
RESULTS: During the follow up period 18 patients developed ISR. Patients with ISR had significantly lower median sFas plasma levels at baseline: 636pg/ml (Interquartile range: 350 –762pg/ml) vs 1038pg/ml (IQR: 387–1383pg/ml); p=0.014 and 24 hours after PCI: 552pg/ml (IQR: 217–554pg/ml) vs 984pg/ml (IQR: 310 –1543pg/ml); p=0.002. In patients with follow up angiography sFas plasma levels before (p=0.039) and after (p=0.007) PCI showed a significant inverse correlation with late lumen loss. Patients in the lowest tertile before PCI had a significantly higher risk of restenosis compared to patients in the highest tertile (adjusted odds ratio: 20). Further patients with the highest decrease in sFAS plasma levels after PCI had significantly higher risk of restenosis. Accordingly patients in the lowest tertile of sFAS plasma levels after stent implantation had the highest risk (adjusted odds ratio: 20)
CONCLUSION: The occurrence of ISR was significantly associated with lower sFAS plasma levels before and after stent placement. We are able to show for the first time that the known proapoptotic and antiinflammatory effects of sFas are important to protect from neointimal lesion formation after vascular injury. Determination of sFAS serum levels might be helpful in the identification of patients with high risk for development of ISR after stent implantation.