External beam irradiation in angioplasted arteries of hypercholesterolemic rabbits

Autor: Ioannis K. Toumpoulis, P. Tsekeris, A. Boziari, Christos S. Katsouras, Lambros K. Michalis, Vassiliki Malamou-Mitsi, Dimitris A. Sideris, Antonia Charchanti, John Kalef-Ezra, G. Bozios
Rok vydání: 2002
Předmět:
Zdroj: Cardiovascular Radiation Medicine. 3:20-25
ISSN: 1522-1865
DOI: 10.1016/s1522-1865(02)00143-9
Popis: Purpose: To study the dose and time effect of external beam irradiation on the morphometry of both angioplasted and nonangioplasted arteries in a hypercholesterolemic rabbit model. Methods and materials: Eight groups of rabbit femoral arteries were studied: arteries (a) with no intervention, (b) irradiated with a 12-Gy 6 MV X-ray dose, (c) with a 18-Gy, (d) treated with balloon angioplasty, (e) dosed with 12-Gy half an hour post-angioplasty, (f) dosed with 18-Gy half an hour post-angioplasty, (g) dosed with 12-Gy 48 h post angioplasty, (g) dosed with 18-Gy 48 h post angioplasty. Results: External irradiation at either 12 or 18 Gy was not found to change vessel morphometry in noninjured arteries . The 12-Gy dose given soon after angioplasty further increased percentage stenosis (63% on the average), despite the preservation of the lumen cross-sectional area. Positive remodeling was not observed in arteries given 18-Gy half an hour post angioplasty to counterbalance the increased neointimal formation. Therefore, this treatment resulted in a drastic reduction in lumen area and in enhancement of percentage stenosis (84% on the average). On the contrary, the delayed irradiation of the angioplasted arteries at either 12 or 18 Gy was not found to influence any of the studied morphometric parameters 5 weeks after angioplasty. Conclusions: Uniform external beam irradiation up to 18 Gy was well tolerated by intact femoral arteries. Prompt 12- or 18-Gy irradiations accentuated percentage stenosis. However the lumen cross-sectional area was preserved only at the lower dose point. Delayed irradiation at any dose did not influence the restenosis process.
Databáze: OpenAIRE