Effects of stent-based delivery of rapamycin and methotrexate on neointimal formation in a porcine coronary model / 中国介入心脏病学杂志

ABSTRACT

Objective To determine the efficacy of stent based rapamycin (Rapa) and methotrexate (MTX) alone or in combination of them to reduce in stent neointimal hyperplasia Rapamycin is a potent immunosuppressive agent that inhibits smooth muscle cell (SMC) proliferation by blocking cell cycle progression Methods Stents were coated with PLGA (poly/lactic co glycolic acid) polymer containing 68-96 ?g Rapa or 250-300 ?g MTX or 58-81 ?g Rapa and 120-170 ?g MTX respectively Twenty five stents (metal, n =8; MTX, n =5; Rapa, n =7; Rapa and MTX, n =5) were implanted in the coronary arteries of 25 pigs Results After 28 days, the mean neointimal thickness was (2 18?1 03) mm 2 in the bare metal stent group; (0 94?0 88) mm 2 in the Rapa group; (0 47?0 24) mm 2 in the combination Rapa and MTX group, (3 93?1 48) mm 2 in the MTX group Compared with metal group the mean neointimal thickness was significantly decresed in Rapa groups and combined group The in stent restenosis was 25% (2/8) in metal group and 80% (4/5) in MTX group after 28 days, and there was no restenosis in the other two groups Conclusion Stent based delivery of Rapa via PLGA polymer can feasibly and effectively reduce in stent neointimal hyperplasia by inhibiting cellular proliferation However there are no effects to reduce in stent neointimal hyperplasia by MTX eluting stents in this study