Heneghan Rachel E, Starnes Benjamin W, Nathan Derek P, Zierler R Eugene
Division of Vascular Surgery, Department of Surgery, University of Washington, Seattle, Wash.
Division of Vascular Surgery, Department of Surgery, University of Washington, Seattle, Wash.
J Vasc Surg. 2016 Apr;63(4):915-21. doi: 10.1016/j.jvs.2015.10.090. Epub 2015 Dec 31.
This study characterized duplex ultrasound (DUS) findings and clinical outcomes associated with covered stent placement in renal arteries during fenestrated endovascular aortic repair (FEVAR) to determine if velocity criteria for native renal artery stenosis can be applied.
Data from a prospectively maintained database of patients who underwent FEVAR between January 2010 and August 2014 were obtained before FEVAR (preoperative or baseline) and at follow-up assessments at 30 days, 6 months, and 1, 2, and 3 years. The established DUS threshold criteria for ≥60% stenosis in native renal arteries were applied at baseline and all follow-up intervals: renal artery peak systolic velocity (PSV) ≥200 cm/s or renal-aortic velocity ratio (RAR) ≥3.5.
Forty-nine patients underwent placement of 88 covered renal artery stents during FEVAR. At least 30-day follow-up was available for 43 patients with 80 stents. A ≥60% stenosis was identified in seven renal arteries of six patients on baseline DUS, and these patients were analyzed separately. The remaining 73 renal arteries were classified as normal or <60% stenosis at baseline, with a median PSV of 121 cm/s (interquartile range, 96-143) and median RAR of 1.4 (interquartile range, 1.1-1.7). No significant differences were found between the baseline and follow-up PSV measurements at any time point. The RAR differed significantly at some time points, although median values remained below the ≥60% stenosis threshold. Some increased RAR values were attributed to low aortic velocities after repair. In the 13 patients with 17 covered renal artery stents found to have PSV or RAR exceeding a DUS threshold for ≥60% native renal artery stenosis, there was no evidence of stenosis by computed tomography angiography, of renal dysfunction by estimated glomerular filtration rate, or of renal volume decrease by three-dimensional analysis. None of the seven renal arteries with ≥60% stenosis at baseline showed evidence of restenosis at 1, 2, or 3 years.
Covered stent placement in nonstenotic renal arteries during FEVAR is safe and durable, with PSV and RAR remaining in the normal or <60% stenosis range in most patients. Increases in PSV or RAR that occur are not associated with clinically significant sequelae or in-stent stenosis on computed tomography angiography. DUS velocity criteria for stenosis in native renal arteries appear to overestimate the severity of stenosis in covered stents after FEVAR.
本研究对开窗式血管腔内主动脉修复术（FEVAR）期间肾动脉覆膜支架置入的双功超声（DUS）检查结果及临床结局进行了特征分析，以确定能否应用天然肾动脉狭窄的流速标准。
获取2010年1月至2014年8月期间接受FEVAR治疗患者的前瞻性维护数据库中的数据，分别于FEVAR术前（术前或基线）以及术后30天、6个月、1年、2年和3年的随访评估时收集。在基线及所有随访期间均应用已确立的天然肾动脉狭窄≥60%的DUS阈值标准：肾动脉收缩期峰值流速（PSV）≥200 cm/s或肾主动脉流速比值（RAR）≥3.5。
49例患者在FEVAR期间置入了88枚肾动脉覆膜支架。43例置入80枚支架的患者至少有30天的随访资料。基线DUS检查发现6例患者的7条肾动脉存在≥60%的狭窄，对这些患者进行了单独分析。其余73条肾动脉在基线时被分类为正常或狭窄<60%，PSV中位数为121 cm/s（四分位间距，96 - 143），RAR中位数为1.4（四分位间距，1.1 - 1.7）。在任何时间点，基线与随访PSV测量值之间均未发现显著差异。尽管中位数仍低于≥60%狭窄阈值，但在某些时间点RAR有显著差异。一些RAR值升高归因于修复术后主动脉流速较低。在13例置入17枚肾动脉覆膜支架且PSV或RAR超过天然肾动脉狭窄≥60%的DUS阈值的患者中，计算机断层血管造影未显示狭窄证据，估算的肾小球滤过率未显示肾功能障碍，三维分析未显示肾体积减小。7条基线狭窄≥60%的肾动脉在1年、2年或3年时均未显示再狭窄证据。
FEVAR期间在无狭窄的肾动脉中置入覆膜支架是安全且持久的，大多数患者的PSV和RAR保持在正常或狭窄<60%的范围内。PSV或RAR升高与临床上显著的后遗症或计算机断层血管造影显示的支架内狭窄无关。天然肾动脉狭窄的DUS流速标准似乎高估了FEVAR术后覆膜支架的狭窄严重程度。
