Department of Vascular Surgery, University Medical Center Utrecht, Utrecht, The Netherlands.
Eur J Vasc Endovasc Surg. 2010 May;39(5):620-6. doi: 10.1016/j.ejvs.2009.12.030. Epub 2010 Feb 12.
Cryoplasty combines conventional angioplasty - percutaneous transluminal angioplasty (PTA) - with cold thermal energy. In this animal study, we investigated if preventive cryoplasty could reduce intimal hyperplasia (IH) at the venous anastomosis.
We investigated cryoplasty versus PTA of the venous anastomosis in a validated porcine, bilateral, arteriovenous graft model.
In 12 pigs, 24 expanded polytetrafluoroethylene (ePTFE) grafts were bilaterally inserted between the common carotid artery and internal jugular vein. Directly after surgery, one venous anastomosis was treated with cryoplasty at -10 degrees C, the contralateral anastomosis with conventional PTA. At 4 weeks, graft flow was measured, quantitative angiography was performed and grafts with adjacent vessels were excised for histological analysis.
Due to a number of thromboses, data for paired analysis were available from eight pigs. Angiographic outflow vein diameter and graft blood flow were not different between treatment groups. Compared with the control group, IH at the venous anastomosis was reduced by 47% (P=0.21) and intima/media ratio was reduced by 45% (P=0.07) by cryoplasty. Effects were most profound in those animals that tended to develop most IH.
Our results suggest that preventive cryoplasty of the venous anastomosis might help to reduce IH in those cases that develop most profound IH.
冷冻成形术将传统的血管成形术 - 经皮腔内血管成形术（PTA） - 与冷热能相结合。在这项动物研究中，我们研究了预防性冷冻成形术是否可以减少静脉吻合口处的内膜增生（IH）。
我们在经过验证的猪双侧动静脉移植物模型中研究了冷冻成形术与 PTA 治疗静脉吻合口的效果。
在 12 头猪中，双侧将 24 个膨胀聚四氟乙烯（ePTFE）移植物插入颈总动脉和颈内静脉之间。手术后，直接对一侧静脉吻合口进行-10°C 的冷冻成形术治疗，对另一侧吻合口进行常规 PTA 治疗。4 周后，测量移植物流量，进行定量血管造影，并切除带有相邻血管的移植物进行组织学分析。
由于发生了一些血栓，只有 8 头猪的数据可进行配对分析。治疗组之间的流出静脉直径和移植物血流量没有差异。与对照组相比，冷冻成形术可使静脉吻合口处的 IH 减少 47%（P=0.21），内膜/中膜比减少 45%（P=0.07）。在那些容易发生最严重 IH 的动物中，效果最为显著。
我们的结果表明，预防性冷冻成形术治疗静脉吻合口可能有助于减少那些容易发生最严重 IH 的病例中的 IH。
