Inflammation and delayed endothelization with overlapping drug-eluting stents in a porcine model of in-stent restenosis.
BACKGROUND
This study evaluated the inflammatory reaction at the site of overlapping drug-eluting stents (DES) in a porcine model of in-stent restenosis.


RESULTS
Twenty bare metal stents (BMS) (group I; n=10), 20 sirolimus-eluting stents (SES) (group II: n=10), 20 paclitaxel-eluting stent (PES) (group III: n=10), and 10 PES and 10 SES (group IV: n=10) were overlapped in the left anterior descending coronary arteries of 40 pigs. Follow-up coronary angiography and histopathology were performed at 4 weeks after stenting. For the overlapped segments, the minimal luminal diameter at 4 weeks was smaller in group I than in the other groups (1.78+/-0.13 mm, 2.79+/-0.09 mm, 2.90+/-0.04 mm, 2.80+/-0.07 mm, respectively; p<0.001), and the neointimal area (5.51+/-0.58 mm2, 2.38+/-0.53 mm2, 2.07+/-0.37 mm2, 2.39+/-0.58 mm2, respectively; p<0.001) and area stenosis (68.74+/-4.02%, 27.79+/-4.73%, 23.66+/-3.24%, 27.63+/-4.07%, respectively; p<0.001) were higher in group I than in the other groups; however, the inflammatory score was higher in group III than in the other groups (1.80+/-0.42, 2.10+/-0.32, 2.90+/-0.31, 2.50+/-0.52, respectively; p<0.001) and the endothelization score was lower in group III than in the other groups (2.80+/-0.42, 2.30+/-0.67, 1.30+/-0.48, 2.10+/-0.74, respectively; p<0.001).


CONCLUSIONS
Compared with BMS, DES inhibit neointimal hyperplasia, but inflammation and poor endothelization occur at the site of overlapping stents.
Lim
Sang Yup
SY
The Cardiovascular Center of Korea University Anam Hospital, Seoul, Korea.
Jeong
Myung Ho
MH
Hong
Soon Jun
SJ
Lim
Do Sun
DS
Moon
Jae Youn
JY
Hong
Young Joon
YJ
Kim
Ju Han
JH
Ahn
Youngkeun
Y
Kang
Jung Chaee
JC
D000818:Animals; D049109:Cell Proliferation; D023903:Coronary Restenosis / Q000209:etiology* / Q000473:pathology*; D023921:Coronary Stenosis / Q000601:surgery; D003331:Coronary Vessels / Q000473:pathology; D004195:Disease Models, Animal; D054855:Drug-Eluting Stents / Q000009:adverse effects*; D004730:Endothelium, Vascular / Q000473:pathology*; D005260:Female; D006965:Hyperplasia / Q000209:etiology / Q000473:pathology; D007249:Inflammation / Q000209:etiology* / Q000473:pathology*; D017239:Paclitaxel; D020123:Sirolimus; D015607:Stents / Q000009:adverse effects; D013552:Swine; D017539:Tunica Intima / Q000473:pathology
D017239:Paclitaxel; D020123:Sirolimus