Reduction of Intimal Hyperplasia with Re-188-labeled Stents in a Rabbit Model at 7 and 26 Weeks: An Experimental Study

Journal Article · Wed Jun 15 04:00:00 EDT 2005 · Cardiovascular and Interventional Radiology

DOI:https://doi.org/10.1007/S00270-004-0308-X· OSTI ID:21091340

Tepe, Gunnar; Dietrich, Tobias; Grafen, Franziska ^[1]; Brehme, Ute ^[2]; Muschick, Peter; Dinkelborg, Ludger M ^[3]; Greschniok, Annette ^[4]; Claussen, Claus D ^[1]; Duda, Stephan H ^[5]

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1. University of Tuebingen, Department of Diagnostic Radiology (Germany)
2. University of Tuebingen, Department of Occupational and Social Medicine (Germany)
3. Research Laboratories of Schering AG (Germany)
4. University of Tuebingen, Institute of Pathology (Germany)
5. Jewish Hospital, Department of Radiology (Germany)

The aim of this study was to analyze the feasibility of {sup 188}Re-labeled stents to reduce neointimal formation in a rabbit atherosclerosis model and to test the long-term effects at 7 and 26 weeks. Fifty-nine male New Zealand White rabbits were fed a 0.5% cholesterol diet for 4 weeks before balloon angioplasty and insertion of Palmaz stents in the infrarenal aorta. The animals were sacrificed 7 and 26 weeks after stent implantation. Control stents were compared with {sup 188}Re stents: (dose 1) 11.3 {+-} 1.8 MBq; (dose 2) 37.3 {+-} 4.2 MBq, and (dose 3) 80.1 {+-} 7.8 MBq. Each activity group consisted of a short-term (7 weeks) and a long-term group (26 weeks), resulting in a total of eight study groups. No thrombotic occlusion was observed. The neointimal formation in the control group was 2.11 [95% confidence interval (CI): 0.68-6.52] mm{sup 2} at 7 weeks and 2.10 (0.62-7.11) at 26 weeks. In the treatment groups, neointima reduction was detectable at 7 weeks [dose 1: 0.33 (0.09-1.22) mm{sup 2}; dose 2: 0.17 (0.05-0.57) mm{sup 2}; dose 3: 0.03 (0.01-0.13) mm{sup 2}]. After 26 weeks, a catch-up of neointimal formation in the radioactive groups was most obvious in the low-dose group [dose 1: 0.80 (0.28-2.29) mm{sup 2}; dose 2: 0.18([0.06-0.52) mm{sup 2}; dose 3: 0.50 (0.17-1.42) mm{sup 2}]. Compared to the long-term control group, neointimal reduction was still >60%. No induction of neointimal formation was observed at the edges of the stents. Radiation resulted in delayed re-endothelialization. {sup 188}Re stents were capable to reduce intimal hyperplasia and did not cause thrombosis. The edge effect, which was the major limitation of {sup 32}P stents, was not observed in {sup 188}Re stents.

• OSTI ID: 21091340
• Journal Information: Cardiovascular and Interventional Radiology, Journal Name: Cardiovascular and Interventional Radiology Journal Issue: 5 Vol. 28; ISSN 0174-1551; ISSN CAIRDG
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
AORTA
ARTERIOSCLEROSIS
CHOLESTEROL
RABBITS
RADIATION DOSES
RHENIUM 188
THROMBOSIS