ISSN:
1435-1803
Keywords:
Key words Restenosis – photodynamic therapy – angioplasty – local drug delivery
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract Background: The effectiveness of local endovascular photodynamic therapy (PDT) in preventing tissue hyperplasia was evaluated in a vascular injury model. Methods: Standardized unidirectional arterial injury with a directional atherectomy catheter was performed in porcine arteries (n = 180). Animals (n = 72) were randomly allocated to unidirectional injury only (Group 1), injury followed by drug delivery of photosensitizer with a porous balloon (Group 2), or by local exposure to monochromatic light (Group 3). In Group 4, injury was followed by local drug delivery of photosensitzier and subsequent exposure to light (PDT). Up to 21 days after treatment, all experimental vessels were excised, fixed and processed for histology, immunohistochemistry and transmission electron microscopy. Results: After vascular injury an inflammatory and myoproliferative response was observed in Groups 1, 2 and 3 (mean tissue hyperplasia/media ratio 1.0 ± 0.5 at 21 days; area tissue hyperplasia: 1.57 ± 0.9 mm2). Proliferation in injured vascular segments (Group 1-3) reached a miximum at 7 days, with 6 %. Only in Group 4, after injury followed by photodynamic therapy, was there no significant vascular response (mean tissue hyperplasia/media ratio 0.3 ± 0.2; area tissue hyperplasia: 0.1 ± 0.05 mm2 p 〉 0.001, proliferating cells 0.3 %). Conclusion: Vascular response after unidirectional injury was suppressed only by endovascular photodynamic therapy.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00788943
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