Morphologic changes in infarct-related plaque after coronary stent placement: a serial angioscopy study.
OBJECTIVE
The aim of this study was to investigate the morphologic changes in infarct-related lesions after stenting in acute or recent myocardial infarction (MI) with coronary angioscopy.


BACKGROUND
There is no information on the serial morphologic changes, which occur after stenting, and the time course of neointimal coverage of stents for disrupted unstable plaques.


METHODS
Forty-three patients with MI within seven days of onset were examined. Angioscopy was serially performed for the infarct-related lesions at baseline (n = 43), after balloon angioplasty (n = 35), and after stenting following balloon angioplasty (n = 39) and at one (n = 36) and six months (n = 30) after stenting.


RESULTS
At baseline, most of the lesions had complex morphology, yellow plaque color, and protruding thrombus (96%, 96%, and 74%, respectively). Although balloon angioplasty reduced the protruding thrombus, it remained in 37%, and an intimal flap was observed in 89% of the lesions. After stenting, the protruding thrombus and intimal flap disappeared, with an increased luminal size obtained in all lesions. At one-month follow-up, an irregular and yellow surface, along with a lining thrombus, was still observed, with partial neointimal stent coverage in most of the lesions. At six-month follow-up, the neointima was found to have sufficiently formed over the stent. The plaque shape and color were almost all classified as smooth (97%) and white (93%).


CONCLUSIONS
These results suggest that a stent not only compressed and covered a disrupted plaque with a protruding thrombus and intimal flap, leading to a wide vessel lumen, but also helped to seal the unstable plaque through neointimal proliferation.
Sakai
Shunta
S
Department of Cardiovascular Center, Chiba-Hokusoh Hospital, Nippon Medical School, Chiba, Japan.
Mizuno
Kyoichi
K
Yokoyama
Shinya
S
Tanabe
Jun
J
Shinada
Takuroh
T
Seimiya
Koji
K
Takano
Masamichi
M
Ohba
Takayoshi
T
Tomimura
Masato
M
Uemura
Ryota
R
Imaizumi
Takahiro
T
D000368:Aged; D017546:Angioscopy; D017023:Coronary Angiography; D003331:Coronary Vessels / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging / Q000473:pathology* / Q000628:therapy*; D015607:Stents; D017539:Tunica Intima / Q000473:pathology