Pontremoli R, Viazzi F, Martinoli C, Ravera M, Nicolella C, Berruti V, Leoncini G, Ruello N, Zagami P, Bezante G P, Derchi L E, Deferrari G
Department of Internal Medicine, Institute of Radiology, University of Genoa, Italy.
Nephrol Dial Transplant. 1999 Feb;14(2):360-5. doi: 10.1093/ndt/14.2.360.
Increased renal resistance detected by ultrasound (US) Doppler has been reported in severe essential hypertension (EH) and recently was shown to correlate with the degree of renal impairment in hypertensive patients with chronic renal failure. However, the pathophysiological significance of this finding is still controversial.
In a group of 211 untreated patients with EH, we evaluated renal resistive index (RI) by US Doppler of interlobar arteries and early signs of target organ damage (TOD). Albuminuria was measured as the albumin to creatinine ratio (ACR) in three non-consecutive first morning urine samples. Left ventricular mass was evaluated by M-B mode echocardiography, and carotid wall thickness (IMT) by high resolution US scan.
RI was positively correlated with age (r=0.25, P=0.003) and systolic blood pressure (SBP) (r=0.2, P=0.02) and with signs of early TOD, namely ACR (r=0.22, P=0.01) and IMT (r=0.17, P<0.05), and inversely correlated with renal volume (r=-0.22, P=0.01) and diastolic blood pressure (r=-0.23, P=0.006). Multiple linear regression analysis demonstrated that age, gender, ACR and SBP independently influence RI and together account for approximately 20% of its variations (F=8.153, P<0.0001). When clinical data were analysed according to the degree of RI, the patients in the top quartile were found to be older (P<0.05) and with higher SBP (P<0.05) as well as early signs of TOD, namely increased ACR (P<0.002) and IMT (P<0.005 by ANOVA), despite similar body mass index, uric acid, fasting blood glucose, lipid profile and duration of hypertension. Furthermore, patients with higher RI showed a significantly higher prevalence of microalbuminuria (13 vs 12 vs 3 vs 33% chi2=11.72, P=0.008) and left ventricular hypertrophy (40 vs 43 vs 32 vs 60%, chi2=9.25, P<0.05).
Increased RI is associated with early signs of TOD in EH and could be a marker of intrarenal atherosclerosis.
超声（US）多普勒检测发现，重度原发性高血压（EH）患者肾血管阻力增加，最近研究表明，这与慢性肾衰竭高血压患者的肾功能损害程度相关。然而，这一发现的病理生理学意义仍存在争议。
在一组211例未经治疗的EH患者中，我们通过叶间动脉的US多普勒评估肾阻力指数（RI）以及靶器官损害（TOD）的早期迹象。在3份非连续的首次晨尿样本中，以白蛋白与肌酐比值（ACR）测定蛋白尿。通过M-B型超声心动图评估左心室质量，通过高分辨率US扫描评估颈动脉壁厚度（IMT）。
RI与年龄（r = 0.25，P = 0.003）、收缩压（SBP）（r = 0.2，P = 0.02）以及TOD的早期迹象呈正相关，即与ACR（r = 0.22，P = 0.01）和IMT（r = 0.17，P < 0.05）呈正相关，与肾体积（r = -0.22，P = 0.01）和舒张压（r = -0.23，P = 0.006）呈负相关。多元线性回归分析表明，年龄、性别、ACR和SBP独立影响RI，共同约占其变异的20%（F = 8.153，P < 0.0001）。当根据RI程度分析临床数据时，发现四分位数最高的患者年龄更大（P < 0.05）、SBP更高（P < 0.05）以及有TOD的早期迹象，即ACR升高（P < 0.002）和IMT升高（方差分析，P < 0.005），尽管体重指数、尿酸、空腹血糖、血脂谱和高血压病程相似。此外，RI较高的患者微量白蛋白尿患病率显著更高（13%对12%对3%对33%，χ2 = 11.7,2，P = 0.008）和左心室肥厚患病率显著更高（40%对43%对32%对60%，χ2 = 9.25，P < 0.05）。
EH患者RI升高与TOD的早期迹象相关，可能是肾内动脉粥样硬化的一个标志物。
