Silverman Steven H, Exline Jessica B, Silverman Larry N, Samson Russell H
Department of Surgery, Florida State University Medical School, Sarasota, Fla.
Department of Surgery, Florida State University Medical School, Sarasota, Fla.
J Vasc Surg. 2014 Dec;60(6):1599-604. doi: 10.1016/j.jvs.2014.08.078. Epub 2014 Oct 3.
Renal artery in-stent restenosis (RAISR) is not an infrequent occurrence and may be in part responsible for the failure of renal stents to improve clinical outcome. A variety of treatments have been used to restore patency, with mixed results. These include repeated percutaneous transluminal renal angioplasty (PTRA), repeated PTRA with bare-metal stents, and repeated PTRA with drug-eluting stents or covered stents. Endovascular brachytherapy (EVBT) has been proven effective in preventing recurrent neointimal hyperplasia in coronary bare-metal stents. This prompted our group to study the effect of EVBT on RAISR.
From 2004 to 2012, 21 patients (23 renal arteries) developed RAISR ≤ 30 months after the initial procedure and were subsequently treated with EVBT. Five patients had at least one prior PTRA for recurrent restenosis. Renal artery duplex scanning was performed as a baseline study within a few days of the EVBT and then every 6 months. All patients who had EVBT were concurrently treated by PTRA and EVBT on the basis of existing protocols. Patency of the treated stents was evaluated by Kaplan-Meier survival curves.
The average onset of the original RAISR was 11 ± 9 months (range, 2-30 months; median, 8 months). The initial technical success of combined PTRA and EVBT was 100%. Mean follow-up was 44 ± 18 months (range, 14-84 months). Of five patients who had PTRA before EVBT, four were available for long-term follow-up. These four patients had a combined total number of five PTRAs before EVBT, with recurrent stenosis developing on average by 12 months. After EVBT, three stents were patent at 39, 48, and 65 months, and one stent restenosed at 42 months. This was the only patient in the entire series to develop restenosis after EVBT.
This retrospective experience with a relatively small number of patients undergoing concurrent EVBT/PTRA for recurrent stenosis in stents placed to treat atherosclerotic renal artery stenosis suggests that EVBT is safe and provides long-term freedom from recurrent stenosis.
肾动脉支架内再狭窄(RAISR)并非罕见,可能部分导致肾支架未能改善临床结局。已采用多种治疗方法来恢复通畅,但结果不一。这些方法包括重复经皮腔内肾血管成形术(PTRA)、带裸金属支架的重复PTRA,以及带药物洗脱支架或覆膜支架的重复PTRA。血管内近距离放射治疗(EVBT)已被证明可有效预防冠状动脉裸金属支架内新生内膜增生复发。这促使我们团队研究EVBT对RAISR的影响。
2004年至2012年,21例患者(23条肾动脉)在初次手术后≤30个月发生RAISR,随后接受了EVBT治疗。5例患者此前至少接受过一次PTRA治疗复发性再狭窄。在EVBT后数天内进行肾动脉双功扫描作为基线研究,然后每6个月进行一次。所有接受EVBT治疗的患者均根据现有方案同时接受PTRA和EVBT治疗。通过Kaplan-Meier生存曲线评估治疗后支架的通畅情况。
最初RAISR的平均发病时间为11±9个月(范围2 - 30个月;中位数8个月)。PTRA和EVBT联合治疗的初始技术成功率为100%。平均随访时间为44±18个月(范围14 - 84个月)。在接受EVBT前接受过PTRA的5例患者中,4例可进行长期随访。这4例患者在接受EVBT前共进行了5次PTRA,平均12个月出现复发性狭窄。EVBT后,3个支架在39、48和65个月时保持通畅,1个支架在42个月时再狭窄。这是整个系列中唯一1例在EVBT后发生再狭窄的患者。
这项对相对少数因治疗动脉粥样硬化性肾动脉狭窄而置入的支架复发性狭窄同时接受EVBT/PTRA治疗患者的回顾性研究表明,EVBT是安全的,并能长期避免复发性狭窄。