Polymer-based paclitaxel-eluting stents reduce in-stent neointimal tissue proliferation: a serial volumetric intravascular ultrasound analysis from the TAXUS-IV trial.
OBJECTIVE
The aim of this study was to use serial volumetric intravascular ultrasound (IVUS) to evaluate the effects of polymer-based, paclitaxel-eluting stents on in-stent neointima formation and late incomplete stent apposition.


BACKGROUND
The TAXUS-IV trial demonstrated that the slow-release, polymer-based, paclitaxel-eluting stent reduces angiographic restenosis and the need for repeat revascularization procedures. Serial IVUS studies reveal details of the pattern of vascular responses provoked by stent implantation that provide insight into device safety and efficacy.


METHODS
In the TAXUS-IV trial, patients were randomized to the slow-release, polymer-based, paclitaxel-eluting TAXUS stent or a bare-metal EXPRESS stent (Boston Scientific Corp., Natick, Massachusetts). As part of a formal substudy, complete volumetric IVUS data were available in 170 patients, including 88 TAXUS patients and 82 controls, at implantation and at nine-month follow-up.


RESULTS
No baseline differences were present in the clinical characteristics or IVUS parameters between the control and TAXUS groups. At nine-month follow-up, IVUS lumen volumes were larger in the TAXUS group (123 +/- 43 mm(3) vs. 104 +/- 44 mm(3), p = 0.005), due to a reduction in neointimal volume (18 +/- 18 mm(3) vs. 41 +/- 23 mm(3), p < 0.001). Millimeter-by-millimeter analysis within the stent demonstrated uniform suppression of neointimal growth along the entire stent length. Late lumen loss was similar at the proximal edge of the stent between the two groups, and reduced with the TAXUS stent at the distal edge (p = 0.004). Incomplete stent apposition at nine months was observed in only 3.0% of control and 4.0% of TAXUS stents (p = 0.12).


CONCLUSIONS
Polymer-based, paclitaxel-eluting TAXUS stents are effective in inhibiting neointimal tissue proliferation, and do not result in late incomplete stent apposition.
Weissman
Neil J
NJ
Washington Hospital Center, Washington, DC 20010, USA. Neil.J.Weissman@medstar.net
Koglin
Joerg
J
Cox
David A
DA
Hermiller
James
J
O'Shaughnessy
Charles
C
Mann
James Tift
JT
Turco
Mark
M
Caputo
Ronald
R
Bergin
Patrick
P
Greenberg
Joel
J
Kutcher
Michael
M
Wong
S Chiu
SC
Strickland
Warren
W
Mooney
Michael
M
Russell
Mary E
ME
Ellis
Stephen G
SG
Stone
Gregg W
GW
D000970:Antineoplastic Agents / Q000008:administration & dosage*; D003327:Coronary Disease / Q000628:therapy; D003331:Coronary Vessels / Q000000981:diagnostic imaging*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D017239:Paclitaxel / Q000008:administration & dosage*; D011108:Polymers; D015607:Stents; D017539:Tunica Intima / Q000000981:diagnostic imaging; D018084:Ultrasonography, Interventional
D000970:Antineoplastic Agents; D011108:Polymers; D017239:Paclitaxel