High incidence of thrombus formation at 18 months after paclitaxel-eluting stent implantation: angioscopic comparison with sirolimus-eluting stent.
BACKGROUND
Difference of neointimal formational pattern and incidence of thrombus formation between sirolimus-eluting stent (SES) and paclitaxel-eluting stent (PES) at 18 months after stent implantation has not previously been reported.


METHODS
We retrospectively enrolled 35 event-free patients who received SES (15 patients, 18 stents) or PES (20 patients, 23 stents) implantation with 18-month follow-up coronary angioscopy. We divided our patients into SES or PES groups and compared neointimal coverage pattern and incidence of red mural thrombus formation between the 2 groups. Neointimal coverage grades were classified into 4 categories. Minimum neointimal coverage grade, maximum grade, and heterogeneity score were assessed in each stent. Heterogeneity score was calculated by subtracting minimum from maximum grade within one stent.


RESULTS
Minimum neointimal coverage grade of PES was significantly lower than that of SES (0.70 +/- 0.64 vs 1.33 +/- 0.69, P = .005), whereas maximum grade was not significantly different (2.48 +/- 0.73 vs 2.22 +/- 0.73, P = .218). Heterogeneity score and incidence of red mural thrombus of PES were higher than those of SES (1.78 +/- 0.80 vs 0.89 +/- 0.76, P = .002 and 70% vs 11%, P < .001).


CONCLUSIONS
The present study revealed that PES shows more heterogeneous neointimal coverage and higher incidence of thrombus formation as compared with SES at 18 months after stent implantation.
Hara
Masahiko
M
Osaka Rosai Hospital, Sakai, Japan. wpgjq774@yahoo.co.jp
Nishino
Masami
M
Taniike
Masayuki
M
Makino
Nobuhiko
N
Kato
Hiroyasu
H
Egami
Yasuyuki
Y
Shutta
Ryu
R
Yamaguchi
Hitoshi
H
Tanouchi
Jun
J
Yamada
Yoshio
Y
D000368:Aged; D015906:Angioplasty, Balloon, Coronary; D017546:Angioscopy; D023903:Coronary Restenosis / Q000517:prevention & control; D003328:Coronary Thrombosis / Q000000981:diagnostic imaging / Q000453:epidemiology*; D003331:Coronary Vessels / Q000000981:diagnostic imaging; D054855:Drug-Eluting Stents; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017239:Paclitaxel / Q000008:administration & dosage; D012189:Retrospective Studies; D020123:Sirolimus / Q000008:administration & dosage; D018084:Ultrasonography, Interventional
D017239:Paclitaxel; D020123:Sirolimus