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Objective To evaluate the efficacy and safty of bioabsorbable polylactic acid sirolimus eluting-stents(BPSES) in inhibiting neointimal hyperplasia in porcine coronary model.Methods Bare metal stents(BMS)(n=18),mere bioabsorbable polylactic acid polymer coated stents(BPOS)(n=18) and BPSES(n=18) were implanted in left anterior descending(n=18),left circumflex coronary(n=18) and right coronary artery(n=18) of 18 swines in random.Coronary angiography was performed 28 days and 90 days after the stenting procedure and histomorphologic analysis was done in a certain number of animals after 7 days(n=4),18 days(n=6) and 90 days(n=6),respectively.Results The 28-day(n=6) and 90-day(n=6) outcome by quantitative coronary angiography(QCA) showed significant reduction in luminal loss(LL) in BPSES(28-day-LL: 0.54?0.45 mm vs 1.11?0.45mm,P=0.048;90-day-LL:0.42?0.34 mm vs 0.96?0.41 mm,P=0.024)compared with BMS.With similar injury scores,histomorphologic analysis on day 28 showed there was a significant reduction in neointimal tissue proliferation with BPSES compared with BMS control(average neointimal area: 0.90?0.40 mm2 vs 1.88?0.71 mm2,P=0.015).High magnification histomorphologic examination revealed similar inflammation score and endothelialization score between BPSES and BMS.Conclusion Bioabsorbable polymeric sirolimus-eluting stents showed reduction in neointimal hyperplasia with good biocompatibility in porcine coronary model.
RESUMO
Objective To evaluate the efficacy and safty of Polymer-free sirolimus eluting-stents(PFSES) in preventing restenosis in porcine coronary model.Methods Bare metal stents(BMS)(n=13),polymer-free bare metal stents(PFBMS)(n=13),polymeric sirolimus-eluting stents(PSES)(n=13) and PFSES(n=13) were implanted in left anterior descending coronary arteries(n=26) and left circumflex coronary(n=26) of 27 swines randomly.Coronary angiography was performed 28 days and 90 days after the procedure.Twelve animals were sacrificed for histomorphologic analysis after 90 days.Results The 28-day(n=24) and 90-day(n=12) outcome by quantitative coronary angiography(QCA) showed significant reduction in luminal loss(LL) in PFSES(LL:0.69?0.49 mm vs 1.27?0.36 mm,P=0.041;0.77?0.44 mm vs 1.33?0.29 mm,P