Dallas Veterans Affairs Medical Center, Dallas, TX, USA.
J Vasc Surg. 2012 Mar;55(3):774-80; discussion 780. doi: 10.1016/j.jvs.2011.10.026. Epub 2012 Jan 21.
This study assessed the longitudinal changes in renal volume after renal artery stenting (RAS) to determine if renal mass is preserved by stenting.
The study cohort consisted of 38 patients with longitudinal imaging available for renal volume quantification before and after RAS. Renal volume was estimated as (kidney length) × (width) × (depth/2) based on preoperative renal imaging. For each patient, the clinical response of blood pressure (BP) and renal function to RAS was categorized according to modified American Heart Association guidelines. Changes in renal volume were assessed using paired nonparametric analyses.
The cohort was a median age of 69 years (interquartile range [IQR], 60-74 years). A favorable BP response was observed in 11 of 38 patients (28.9%). At a median interval between imaging studies of 21 months (IQR, 13-32 months), ipsilateral renal volume was significantly increased from baseline (146.8 vs 133.8 cm(3);P = .02). This represents a 6.9% relative increase in ipsilateral kidney volume from baseline. A significant negative correlation between preoperative renal volume and the relative change in renal volume postoperatively (r = -0.42; P = .0055) suggests that smaller kidneys experienced the greatest gains in renal volume after stenting. It is noteworthy that the 25 patients with no change in BP or renal function-clinical failures using traditional definitions-experienced a 12% relative increase in ipsilateral renal volume after RAS. Multivariate analysis determined that stable or improved renal volume after stenting was an independent predictor of stable or improved long-term renal function (odds ratio, 0.008; 95% confidence interval, 0.000-0.206; P = .004).
These data lend credence to the belief that RAS preserves renal mass in some patients. This benefit of RAS even extends to those patients who would be considered treatment failures by traditional definitions. Patients with stable or increased renal volume after RAS had more stable renal function during long-term follow-up, whereas patients with renal volume loss after stenting were prone to deterioration of renal function.
本研究旨在评估肾动脉支架置入（RAS）后肾脏体积的纵向变化，以确定支架置入是否能保留肾质量。
研究队列包括 38 例有纵向影像学资料可供肾体积定量的患者。根据术前肾影像学检查，肾脏体积估计为（肾长）×（宽）×（深度/2）。根据美国心脏协会的改良指南，对每位患者 RAS 后血压（BP）和肾功能的临床反应进行分类。使用配对非参数分析评估肾脏体积的变化。
该队列的中位年龄为 69 岁（四分位距 [IQR]，60-74 岁）。38 例患者中有 11 例（28.9%）观察到血压反应良好。在中位数为 21 个月（IQR，13-32 个月）的影像学研究间隔期间，对侧肾脏体积从基线显著增加（146.8 比 133.8 cm³；P =.02）。这代表对侧肾脏体积从基线增加了 6.9%。术前肾脏体积与术后肾脏体积相对变化之间存在显著负相关（r = -0.42；P =.0055），提示体积较小的肾脏在支架置入后肾脏体积增加幅度最大。值得注意的是，25 例血压或肾功能无变化的患者（传统定义的临床失败）在 RAS 后对侧肾脏体积相对增加了 12%。多变量分析确定支架置入后稳定或改善的肾脏体积是稳定或改善长期肾功能的独立预测因子（优势比，0.008；95%置信区间，0.000-0.206；P =.004）。
这些数据为 RAS 在某些患者中保留肾质量的观点提供了依据。即使对于那些根据传统定义被认为是治疗失败的患者，RAS 也有这种获益。RAS 后肾脏体积稳定或增加的患者在长期随访期间肾功能更稳定，而支架置入后肾脏体积减少的患者更容易发生肾功能恶化。
