Delayed neointimalization on sirolimus-eluting stents: 6-month and 12-month follow up by optical coherence tomography.
BACKGROUND
Sirolimus-eluting stents (SES) have incomplete neointimal coverage at 6-month follow up as determined with optical coherence tomography (OCT). The long-term detailed changes of neointima in SES remains to be clarified.


RESULTS
Serial changes in neointimal coverage of SES from 6 months to 12 months using OCT were examined. Of 21 SES in 13 patients, OCT was used to visualize 2,321 stent struts at 6 months and 2,285 stent struts at 12 months. The frequency of struts without neointimal coverage decreased from 6 months to 12 months (from 10.4 to 5.7%). The frequency of malapposed struts decreased from 6 months to 12 months (from 1.7 to 0.2%). The average thickness of the neointima increased (from 112 +/-123 to 120 +/-130 microm). The frequency of struts located at the side branch orifice without neointima decreased (from 4 out of 17 (24%) to 0 out of 17 (0%)). Complete coverage with neointima was observed in 14% (3 of 21 SES) at 6 months, and 24% (5 of 21 SES) at 12 months.


CONCLUSIONS
Additional neointimal coverage was observed between 6 and 12 months, with a small increase in the neointimal thickness. The incidence of complete coverage, however, was still low at 12 months. These findings suggest delayed neointimalization on SES.
Katoh
Hiroki
H
Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine.
Shite
Junya
J
Shinke
Toshiro
T
Matsumoto
Daisuke
D
Tanino
Yusuke
Y
Ogasawara
Daisuke
D
Sawada
Takahiro
T
Miyoshi
Naoki
N
Kawamori
Hiroyuki
H
Yoshino
Naoki
N
Hirata
Ken-ichi
K
D000368:Aged; D003328:Coronary Thrombosis / Q000453:epidemiology / Q000503:physiopathology; D003331:Coronary Vessels / Q000473:pathology / Q000503:physiopathology*; D054855:Drug-Eluting Stents; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009389:Neovascularization, Pathologic / Q000175:diagnosis* / Q000503:physiopathology*; D012307:Risk Factors; D020123:Sirolimus; D013997:Time Factors; D041623:Tomography, Optical Coherence; D017539:Tunica Intima / Q000473:pathology / Q000503:physiopathology*
D020123:Sirolimus