Time course of stent endothelialization after intravascular radiation therapy in rabbit iliac arteries

Article

关键词: INTRACORONARY BETA-RADIATION;    BALLOON OVERSTRETCH INJURY;    PORCINE CORONARY-ARTERIES;    GAMMA-RADIATION;    WASHINGTON RADIATION;    INHIBITS RECURRENCE;    LATE THROMBOSIS;    WRIST-PLUS;    RESTENOSIS;    IRRADIATION;   

DOI  :  10.1161/01.CIR.0000062648.39025.09

来源: SCIE

【 摘 要 】

Background-Late total occlusion after vascular brachytherapy (VBT) continues to be a serious complication. Delayed reendothelialization was suggested as a pivotal cause, but the time course for complete healing is unknown. Methods and Results-Seventy-two rabbit iliac arteries underwent stent implantation and were treated with gamma-radiation using Ir-192. The prescribed doses were 0 Gy (controls, n=24 arteries), 15 Gy (n=24), or 30 Gy (n=24) at 2 mm. Animals were killed at 1 month (n=24), 3 months (n=24), or 6 months (n=24) and were analyzed for histomorphometry or scanning electron microscopy. Intimal area was reduced after VBT at 3 months with 15 and 30 Gy (0.66+/-0.07 and 0.66+/-0.04 mm(2), respectively) compared with controls (1.01+/-0.11 mm(2), P<0.05) and at 6 months with 30 Gy (0.75+/-0.09 versus 1.28+/-0.26 mm(2) in controls, P<0.01). Intimal area was similar at 6 months between 15 Gy and controls. At 1 month, 92+/-4% of the control stented segment was covered with endothelial cells, whereas only 37+/-4% and 37+/-8% was covered in the 15- and 30-Gy arteries, respectively. Similarly, at 3 and 6 months, there was a difference in the extent of reendothelialized areas (at 3 months, 95+/-2%, 32+/-12%, and 29+/-13%; and at 6 months, 98+/-2%, 40+/-8%, and 35+/-12% in control, 15-Gy, and 30-Gy arteries, respectively). Excess platelets and leukocytes were seen in irradiated arteries without complete coverage of endothelium. Conclusions-Reendothelialization after VBT is not completed at 6 months after VBT. Special care with prolonged antiplatelet therapy should be considered beyond that time point.

【 授权许可】

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