Incomplete stent apposition after implantation of paclitaxel-eluting stents or bare metal stents: insights from the randomized TAXUS II trial.
BACKGROUND
The clinical impact of late incomplete stent apposition (ISA) for drug-eluting stents is unknown. We sought to prospectively investigate the incidence and extent of ISA after the procedure and at 6-month follow-up of paclitaxel-eluting stents in comparison with bare metal stents (BMS) and survey the clinical significance of ISA over a period of 12 months.


RESULTS
TAXUS II was a randomized, double-blind study with 536 patients in 2 consecutive cohorts comparing slow-release (SR; 131 patients) and moderate-release (MR; 135 patients) paclitaxel-eluting stents with BMS (270 patients). This intravascular ultrasound (IVUS) substudy included patients who underwent serial IVUS examination after the procedure and at 6 months (BMS, 240 patients; SR, 113; MR, 116). The qualitative and quantitative analyses of ISA were performed by an independent, blinded core laboratory. More than half of the instances of ISA observed after the procedure resolved at 6 months in all groups. No difference in the incidence of late-acquired ISA was observed among the 3 groups (BMS, 5.4%; SR, 8.0%; MR, 9.5%; P=0.306), with a similar ISA volume (BMS, 11.4 mm3; SR, 21.7 mm3; MR, 8.5 mm3; P=0.18). Late-acquired ISA was the result of an increase of vessel area without change in plaque behind the stent. Predictive factors of late-acquired ISA were lesion length, unstable angina, and absence of diabetes. No stent thrombosis occurred in the patients diagnosed with ISA over a period of 12 months.


CONCLUSIONS
The incidence and extent of late-acquired ISA are comparable in paclitaxel-eluting stents and BMS. ISA is a pure IVUS finding without clinical repercussions.
Tanabe
Kengo
K
Thoraxcenter, Erasmus MC, Rotterdam, The Netherlands.
Serruys
Patrick W
PW
Degertekin
Muzaffer
M
Grube
Eberhard
E
Guagliumi
Giulio
G
Urbaszek
Wilhelm
W
Bonnier
Johannes
J
Lablanche
Jean-Michel
JM
Siminiak
Tomasz
T
Nordrehaug
Jan
J
Figulla
Hans
H
Drzewiecki
Janusz
J
Banning
Adrian
A
Hauptmann
Karl
K
Dudek
Dariusz
D
Bruining
Nico
N
Hamers
Ronald
R
Hoye
Angela
A
Ligthart
Jurgen M R
JM
Disco
Clemens
C
Koglin
Jörg
J
Russell
Mary E
ME
Colombo
Antonio
A
D000368:Aged; D020099:Coated Materials, Biocompatible / Q000627:therapeutic use; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D017239:Paclitaxel / Q000008:administration & dosage*; D019919:Prosthesis Implantation / Q000009:adverse effects / Q000592:standards*; D012307:Risk Factors; D015607:Stents / Q000009:adverse effects*; D018084:Ultrasonography, Interventional
D020099:Coated Materials, Biocompatible; D017239:Paclitaxel