The pattern of restenosis and vascular remodelling after cold-end radioactive stent implantation.
BACKGROUND
Edge restenosis is a major problem after radioactive stenting. The cold-end stent has a radioactive mid-segment (15.9 mm) and non-radioactive proximal and distal 5.7 mm segments. Conceptually this may negate the impact of negative vascular remodelling at the edge of the radiation.


RESULTS
ECG-gated intravascular ultrasound with three-dimensional reconstruction was performed post-stent implantation and at the 6-month follow-up to assess restenosis within the margins of the stent and at the stent edges in 16 patients. Angiographic restenosis was witnessed in four patients, all in the proximal in-stent position. By intravascular ultrasound in-stent neointimal hyperplasia, with a >50% stented cross-sectional area, was seen in eight patients. This was witnessed proximally (n=2), distally (n=2) and in both segments (n=4). Echolucent tissue, dubbed the 'black hole' was seen as a significant component of neointimal hyperplasia in six out of the eight cases of restenosis. Neointimal hyperplasia was inhibited in the area of radiation: Delta neointimal hyperplasia=3.72 mm3 (8.6%); in-stent at the edges of radiation proximally and distally Delta neointimal hyperplasia was 7.9 mm3 (19.0%) and 11.4 mm3 (25.6%), respectively (P=0.017). At the stent edges there was no significant change in lumen volume.


CONCLUSIONS
Cold-end stenting results in increased neointimal hyperplasia in in-stent non-radioactive segments.
Kay
I P
IP
Thoraxcenter, Rotterdam, The Netherlands.
Wardeh
A J
AJ
Kozuma
K
K
Sianos
G
G
Regar
E
E
Knook
M
M
van der Giessen
W J
WJ
Thury
A
A
Ligthart
J M
JM
Coen
V M
VM
Levendag
P C
PC
Serruys
P W
PW
D001918:Brachytherapy; D002455:Cell Division / Q000528:radiation effects; D003327:Coronary Disease / Q000473:pathology / Q000628:therapy*; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000473:pathology* / Q000528:radiation effects; D006801:Humans; D006965:Hyperplasia / Q000000981:diagnostic imaging / Q000517:prevention & control; D010761:Phosphorus Radioisotopes / Q000627:therapeutic use; D055502:Secondary Prevention; D015607:Stents / Q000009:adverse effects; D017539:Tunica Intima / Q000473:pathology*; D018084:Ultrasonography, Interventional
D010761:Phosphorus Radioisotopes