Vascular response to coronary artery stenting in mature and juvenile swine

Abstract Purpose The objective of this study was to investigate potential differences in vascular response to stenting of coronary arteries with bare metal (BMS) and drug-eluting (DES) stents in juvenile vs. mature swine. Methods and materials Twenty-one mature (>3 years) and 22 juvenile (6-9 months) Yucatan swine were implanted with 3×12-mm XIENCE V DES and ML VISION BMS in coronary arteries. After 7 and 28 days, vessels were analyzed using light microscopy ( n =5–7) and confocal and scanning electron microscopy ( n =5–10). Messenger RNA expression levels of inflammatory and endothelial gene markers were tested from stented tissue at 7 and 28 days ( n =3). A 2 × 2 analysis of variance followed by t tests compared treatment and/or age effects. Results No age differences in neointimal area and percentage stenosis were measured. Juvenile swine exhibited increased fibrin scores compared to mature swine (2.6±0.5 vs. 2.2±0.5, P