Carbon Coating Has No Effect on Inflammatory Response to Primary Stent Deployment

To investigate the effects of carbon-coating of stents on inflammatory response we serially measured plasma levels of C-reactive protein (CRP), fibrinogen and cytokines (tumor necrosis factor, interleukins 1-b, 6 and 8) in patients with single vessel coronary stenosis with no any inflammatory or infectious disease who underwent primary stent insertion. Forty-six patients with single coronary lesions were included. Blood samples were obtained before and 2, 4, 6, 24 and 48 hours after the procedure. In a randomized order, either an uncoated MAC (AMG® Raesfeld-Erle, Germany) (UC-MAC) or a carbon-coated MAC (CC-MAC) stents was deployed without predilatation at a maximum pressure of 6 atmospheres for a duration of 90 seconds. Of the 46 patients (38 male, 8 female; age 55 ± 9) included. Fourteen had stable, 27 unstable and 5 atypical angina. According to the ACC / AHA classification 35 lesions (76.1%) were type A, 10 (21.7%) type B and 1 (2.2%) were type C. Stents implanted to stenosis of 28 left anterior descending, 12 circumflex and 6 right coronary arteries. Serum interleukin 6 (IL-6) levels increased significantly in both CC-MAC and UC-MAC groups and returned to normal after 24 hours. Plasma fibrinogen, CRP levels and leukocyte counts also increased in both groups (p<0.05). There was no difference between the two groups in regard to IL-6, CRP and fibrinogen increase. The percent increase in IL-6, fibrinogen or CRP levels were not associated with the stent length, stent size or the clinical presentation (all p>0.05). In conclusion stent implantation increases plasma IL- 6, fibrinogen and CRP levels. This unfavorable inflammatory response seems not to be effected by carbon coating.