ABSTRACT
BACKGROUND: Carvedilol is a beta- and alpha-receptor blocker, a direct inhibitor of smooth muscle cell proliferation and migration, and produces a significant suppression of neointimal hyperplasia in rat carotid injury model. We tested whether carvedilol stent coating is effective in preventing neointimal formation in a porcine model of stent restenosis. METHODS: BiodivYsio phosphorylcholine-coated stents were dip-coated with carvedilol at the concentrations of 0, 7, 96 and 154 micrometer/stent by the immersion in a methanolic carvedilol followed by the evaporation of the solvent. Thirty-two stents, 8 stents per each concentration, were deployed in the porcine coronary arteries. The treatment effect was assessed at 28 days after stent implantation. RESULTS: Angiographic minimal lumen diameter and late loss index were similar among the four groups. On histomorphometry, neointimal area decreased by 58% and lumen area increased by 20%, resulting in a 58% reduction of percent in-stent stenosis in 7 micrometer carvedilol/stent (p=0.002, 0.008 and 0.004, respectively, 7 micrometer vs. 0 micrometer carvedilol/stent). Modest change in neointimal and lumen area was observed in 96 and 154 micrometer carvedilol/stent. A proliferating nuclear cell antigen-positive cells was noted 7.78 +/- 2.97% in 7 micrometer carvedilol/stent vs. 17.82 +/- 1.45% in 0 micrometer carvedilol/stent (p=0.0001). CONCLUSION: A Low dose carvedilol stent coating produces a significant inhibition of neointimal hyperplasia in a porcine model of stent restenosis. This study provides a potential therapeutic benefit of carvedilol coating in the prevention of human stent restenosis.