Hiramoto Jade, Hansen Kimberley J, Pan Xian Mang, Edwards Matthew S, Sawhney Rajiv, Rapp Joseph H
University of California, San Francisco, USA.
J Vasc Surg. 2005 Jun;41(6):1026-30. doi: 10.1016/j.jvs.2005.02.042.
We hypothesized that atheroemboli released during renal angioplasty could be responsible for the modest functional result of renal angioplasty even after anatomic reduction of renal artery stenosis. To test this hypothesis, we enumerated and sized fragments released during ex vivo angioplasty and stenting of human renal artery atherosclerotic specimens removed during aortorenal endarterectomy.
Thirty-three intact aortorenal atheroma specimens (16 pairs with adjacent aortic atheroma and one specimen with a single renal artery orifice) were removed from 17 patients with renal artery occlusive disease who underwent renal artery endarterectomy. specimens. Endarterectomy specimens were removed with a ring of aortic plaque and "fitted" with a polytetrafluoroethylene "adventitia". Ex vivo angioplasty was technically successful in 31 of the 33 specimens and was performed by using a 0.018-inch guidewire and 3.0-mm and 5.0-mm angioplasty balloons inflated for 30 seconds at 15 atmospheres pressure. Stenting was performed with either a 5-mm or 6-mm self-expanding Wallstent. Each artery was flushed with 20 mL of saline after guidewire placement, each angioplasty, and stent placement. The effluent was collected for analysis for counting with either a microscope (size >100 microm) or a Coulter counter (size <100 microm). The number and size of embolic fragments in the effluent collected after each manipulation was recorded.
Each manipulation of the specimens, including simply advancing the guidewire through the atherosclerotic lesion, released thousands of fragments. The numbers of fragments in each size category increased with decreasing particle size. Positioning and deploying the Wallstent released an additional bolus of fragments similar to that released after balloon angioplasty.
Ex vivo renal angioplasty releases thousands of atherosclerotic fragments of sufficient size to create vascular occlusions and initiate significant renal parenchymal damage. The results of renal angioplasty procedures could be improved by placing distal protection devices to prevent atheroembolization.
Athero-emboli produce a local arteritis in the kidney and could cause substantial damage to the renal parenchyma. This report explores the quantity of athero-emboli released during ex vivo angioplasty and stenting of renal atheroma specimens. The number of emboli found in this ex vivo study suggest that the use of protection devices may be advisable to protect the end organ, as done with angioplasty of the carotid artery. Of necessity, this was an ex vivo study and direct application to the clinical setting will need further study. Fortunately, multi-center trials examining the value of protection devices are currently in progress.
我们推测，即使在肾动脉狭窄解剖学上减轻后，肾血管成形术期间释放的动脉粥样硬化栓子可能是肾血管成形术功能结果一般的原因。为了验证这一假设，我们对在主动脉肾动脉内膜切除术期间切除的人肾动脉粥样硬化标本进行体外血管成形术和支架置入过程中释放的碎片进行了计数和测量大小。
从17例接受肾动脉内膜切除术的肾动脉闭塞性疾病患者中取出33个完整的主动脉肾动脉粥样瘤标本（16对伴有相邻主动脉粥样瘤，1个标本有单个肾动脉开口）。标本连同一圈主动脉斑块一起取出，并“安装”聚四氟乙烯“外膜”。33个标本中有31个在体外血管成形术在技术上取得成功，使用0.018英寸导丝以及3.0毫米和5.0毫米血管成形术球囊在15个大气压下充气30秒进行操作。使用5毫米或6毫米自膨式Wallstent支架进行支架置入。在放置导丝、每次血管成形术和支架置入后，每条动脉用20毫升生理盐水冲洗。收集流出物进行分析，用显微镜（尺寸>100微米）或库尔特计数器（尺寸<100微米）计数。记录每次操作后收集的流出物中栓塞碎片的数量和大小。
对标本的每次操作，包括简单地将导丝推进穿过动脉粥样硬化病变，都会释放数千个碎片。每个尺寸类别的碎片数量随着颗粒尺寸的减小而增加。定位和展开Wallstent支架会释放额外的一团碎片，类似于球囊血管成形术后释放的碎片。
体外肾血管成形术会释放数千个大小足以造成血管闭塞并引发显著肾实质损伤的动脉粥样硬化碎片。通过放置远端保护装置以防止动脉粥样硬化栓塞，肾血管成形术的结果可能会得到改善。
动脉粥样硬化栓子在肾脏中产生局部动脉炎，并可能对肾实质造成严重损害。本报告探讨了在肾动脉粥样瘤标本的体外血管成形术和支架置入过程中释放的动脉粥样硬化栓子的数量。在这项体外研究中发现的栓子数量表明，与颈动脉血管成形术一样，使用保护装置可能有助于保护终末器官。当然，这是一项体外研究，直接应用于临床情况还需要进一步研究。幸运的是，目前正在进行多中心试验来检验保护装置的价值。
