Posttransplant renal artery stenosis: angiographic study in 32 children

Renal artery stenosis was identified in 32 children who either developed or had an exacerbation of hypertension after renal transplantation. One child developed renal artery stenosis in two sequential transplants. Renal artery stenosis occurred only in those patients who received transplants from cadavers. In 14 of the 15 patients with end-to-end renal artery anastomoses, the stenosis was at the anastomosis. In 14 of the 18 patients with end-to-side anastomoses, the stenosis was distal to the anastomosis.     

粥样硬化性肾动脉狭窄与颅内-外动脉狭窄的关系

目的 探讨肾动脉粥样硬化性狭窄(ARAS)与颅内-外动脉狭窄的关系.方法 对304例疑为颅内-外动脉狭窄的患者行颅内-外动脉造影,同时作双侧肾动脉造影,了解颅内-外动脉和ARAS情况,对临床资料和ARAS的关系进行统计分析.结果 304例患者中颅内-外动脉狭窄186例,ARAS 90例(患病率29.6%).186例颅内-外动脉狭窄患者合并ARAS 77例,罹患率41.4%(77/186).单纯ARAS患者13例,患病率11.0%(13/118).ARAS在颅内-外动脉狭窄病变组中的罹患率明显高于无颅内-外血管病变组,两组间差异具有统计学意义(P<0.05).在颅内-外动脉狭窄组中,中-重度或多支颅内-外动脉狭窄者ARAS发病率高.结论 对有颅内-外动脉狭窄病变的患者造影后,应常规行肾动脉造影,以便早期发现ARAS.     

Carotid-anterior cerebral artery anastomosis: MR angiographic features and literature review

Carotid-anterior cerebral artery anastomosis is a rare anomaly of the anterior part of the circle of Willis. We report here magnetic resonance (MR) angiographic findings in 2 patients with this anomaly. MR angiographic source images are useful in evaluating the anatomical details of this anomaly. Including the 2 present cases, 27 patients with this anomaly have been reported in the English-language literature. Thirty anomalous arteries were found in the 27 patients (R/L/bilateral=22/2/3). The reason for the right-sided predominance is unknown.     

多层螺旋CT血管造影术诊断动脉粥样硬化性肾动脉狭窄的价值

目的 探讨多层螺旋CT血管造影(MSCTA)诊断动脉粥样硬化性肾动脉狭窄(ARAS)的必要性和可靠性.方法 选取82例曾做过数字减影血管造影(DSA)的ARAS患者行肾动脉MSCTA,将所获得的图像数据进行多平面重建、最大密度投影法重建、容积重建和表面阴影遮盖法重建,将结果与DSA进行对比分析.结果 ①MSCTA发现狭...     

Complications during renal artery stent placement for atherosclerotic ostial stenosis

Purpose To describe short-term complications during stent placement for atherosclerotic renal artery ostial stenosis. Methods Sixty-one arteries in 50 patients were treated with Palmaz stents. Nineteen patients had a single functioning kidney, 23 had a bilateral stenosis, which was stented bilaterally in 11, and 8 had a unilateral stenosis. The complications were grouped as those related to the catheterization procedure, those related to stent placement, and those possibly related to either category. The complications were divided into those with severe clinical significance (SCS), those with minor clinical significance (MCS), and radiological-technical complications (RTC). The stent placement procedures were ordered chronologically according to examination date and the complications were tabulated per group of 10 patients. Results Five (10%) SCS, 5 (10%) MCS, and 8 (16%) RTC occurred in 50 patients. The catheterization procedure led to 2 SCS, 3 MCS, and 1 RTC. Stent placement gave rise to 7 RTC. Three SCS and 2 MCS could have been related to either catheterization or stent placement. More SCS occurred in the first group of 10 patients than in the following groups. Conclusion Renal artery stent placement for atherosclerotic ostial stenosis has a considerable complication rate and a learning curve is present. The complications related to the actual stent placement were without clinical consequences.     

The angiographic incidence of renal artery stenosis in the arteriosclerotic population

The incidence of renal artery stenosis was evaluated with intra-arterial digital subtraction angiography in 100 consecutive patients referred for peripheral arteriopathy. Fifty-seven patients were normotensive, 43 were hypertensive. In the normotensive group, renal artery stenosis was found in ten patients (17.5%). In the hypertensive group renal artery stenosis was found in twelve patients (28%). It is concluded that the incidence of renal artery stenosis is high in an arteriosclerotic population both in normotensive and hypertensive patients.     

Diffusion-weighted MR imaging of kidneys in renal artery stenosis

OBJECTIVE: The purpose of our study was to evaluate perfusion and diffusion of kidneys in renal artery stenosis (RAS) and any correlation between stenosis and ADC values and whether this imaging modality may be a noninvasive complementary assessment technique to MR angiography before interventional procedures. MATERIALS AND METHODS: Twenty consecutive patients suspected of having renal artery stenosis were evaluated with renal MR angiography to exclude stenosis and were then included in the study. Transverse DW multisection echo-planar MR imaging was performed. In the transverse ADC map, rectangular regions of interest were placed in the cortex on 3 parts (upper, middle, and lower poles) in each kidney. ADCs of the kidneys were calculated separately for the low, average, and high b-values to enable differentiation of the relative influence of the perfusion fraction and true diffusion. The ADC values of 39 kidneys (13 with renal artery stenosis and 26 normal renal arteries) were compared, and the relationship between stenosis degree and ADC values was calculated. RESULTS: RAS was detected in 11 of 20 (55%) patients with MRA. Thirteen of 39 kidneys demonstrated RAS, and 26 were normal. The ADClow (1.9+/-0.2 versus 2.1+/-0.2; P=.020), ADCaverage (1.7+/-0.2 versus 1.9+/-0.1; P=.006), and ADChigh (1.8+/-0.2 versus 2.0+/-0.1; P=.012) values were significantly lower in patients with kidneys with arterial stenosis than that in patients with kidneys with normal arteries. Statistical analysis revealed that stenosis degree correlated strongly with ADClow (r=-.819; P=.001), ADCaverage (r=-.754; P=.003), and ADChigh (r=-.788; P=.001). The ADClow, ADCaverage, and ADChigh values were significantly lower in patients with kidneys with arterial stenosis than that in patients with kidneys with normal arteries. CONCLUSION: We think that DW MR imaging of kidneys with RAS can help determine the functional status of a renal artery stenosis.     

Craniocervical artery dissection: MR imaging and MR angiographic findings

Dissection of the carotid and vertebral arteries is a not so uncommon cause of stroke and has to be considered as a differential diagnosis especially in younger patients. Therapeutic and prognostic implications are different from those in extracranial atherosclerotic disease. Dissection results from hemorrhage into the vessel wall usually between the layers of the media. Digital subtraction angiography (DSA) depicts the resulting luminal compromise that may reveal some typical, but not specific, findings. The same is true for non-invasive angiographic techniques such as time-of-flight magnetic resonance angiography (MRA) and computed tomography angiography (CTA), which have shown accurate results compared with DSA. The main advantage of these techniques is the direct visualization of the vessel wall confirming the intramural hematoma. This is achieved best with MR imaging due to the high signal of blood degradation products on T1- and T2-weighted images. Therefore, MRI in combination with MRA is presently the method of choice for initial diagnosis and follow-up of craniocervical artery dissection (CCAD). In some questionable cases, CTA is a non-invasive alternative that is independent of flow phenomena. Received: 4 May 1998; Revision received: 8 September 1998; Accepted: 10 November 1998     

The prevalence and clinical predictors of incidental atherosclerotic renal artery stenosis

Objective

To evaluate the prevalence of incidental renal artery stenosis due to atherosclerosis and associated risk factors in patients with peripheral arterial disease (PAD).

Materials and methods

To determine renal artery stenosis, aortofemoropopliteal digital substraction angiographies (DSA) of 629 consecutive patients with PAD were prospectively reviewed. Angiographies were performed as catheter angiography with automated pump injection. Of the patients, 540 were male (86%) and 89 female (14%) (mean age ± S.D.: 61.5 ± 11.1 years). Statistical analysis was performed to determine the association of significant renal artery stenosis (≥60% diameter stenosis) with patient demographics (age, sex, reason for angiography and smoking status), medical history (diabetes mellitus, hypertension and coronary artery disease), laboratory values (blood creatinine, fasting glucose, triglycerides, LDL, HDL and total cholesterol) and distribution of PAD (aortoiliac, femoropopliteal and crural diseases and multisegment involvement).

Results

Renal artery disease was found in 33% (207 of 629) of all patients with peripheral arterial disease, and 9.6% of patients (n = 60) had significant (≥60%) renal artery stenosis. Only age and hypertension (blood pressure systolic >140 mmHg or diastolic >90 mmHg) were independent risk factors for significant renal artery stenosis on multivariate analysis. Mean age of patients with RAS was 66.5 ± 8.9 years compared with 61 ± 11.2 years for patients without RAS (p < 0.001). Hypertension was found in 41% of the patients in control group and in 63% of the patients in RAS group (p = 0.01).

Conclusion

Incidental renal artery stenosis which can be mild or significant is a relatively common finding among patients with peripheral arterial disease. Advance age and hypertension are closely associated with significant renal artery stenosis.     

Low-profile stent system for treatment of atherosclerotic renal artery stenosis: the GREAT trial

PURPOSE: The Palmaz Genesis Peripheral Stainless Steel Balloon Expandable Stent in Renal Artery Treatment (GREAT) Trial was designed to assess the safety and performance of a low-profile stent for the treatment of obstructive renal artery disease by looking at 6-month renal artery patency uniformly analyzed by a Core Lab. MATERIALS AND METHODS: Fifty-two consecutive patients (mean age, 63.7 years) were successfully treated with the Palmaz Genesis Peripheral Stent (Cordis, Miami, FL) on the Slalom 0.018-inch Delivery System (Cordis Europe N.V., Oosteinde 8, NLO-9301 LJ Roden, The Netherlands) at 11 investigational centers. Patients with severe renal failure and > 8-mm renal artery were excluded. Primary endpoint was angiographic determination of in-stent percent diameter stenosis at 6 months. Fifty-one patients were treated with one stent, one patient was treated with two stents to cover the complete lesion. RESULTS: Mean percentage diameter stenosis before renal angioplasty was 68.2% +/- 12.0%. No stent implantation failure, displacement, need for additional stent implantation, or procedural complication was observed. Six-month angiography was performed in 41 of 52 patients (79%) resulting in a mean in-stent percent diameter stenosis or Quantitative Vessel analysis (QVA) at 6 months of 23.9%. The in-stent binary (percent diameter stenosis > 50%) restenosis rate at 6 months was 14.3%. No fatal events occurred up to 6 months after implantation. Major adverse events occurred in five patients: four patients (7.7%) required a revascularization and one patient (1.9%) experienced a cerebrovascular event, which regressed spontaneously. CONCLUSIONS: The Palmaz Genesis stent (Cordis) provides good results for renal artery stent placement, with an in-stent binary restenosis rate (percent diameter stenosis > 50%) at 6 months of 14.3% as determined with angiography.     

动脉粥样硬化性肾动脉狭窄的介入诊断与治疗方法探讨

目的　观察动脉粥样硬化所致的肾动脉狭窄的发生率 ,及经皮肾动脉球囊成形术 (PTRA)加支架术的疗效。方法　对连续 2 0 0例接受冠状动脉 (冠脉 )造影的患者用Judkins右冠脉造影导管作选择性肾动脉造影或腹主动脉数字减影血管造影 (DSA)进行肾动脉造影 ,并对其中 7例肾动脉严重狭窄 (狭窄直径≥ 85 % )患者的 8支狭窄血管行PTRA加支架术 ,所有病变均为动脉粥样硬化所致。结果　 2 0 0例受检者中 ,肾动脉狭窄的发生率为 10 .5 % (2 1例 ) ;其中 ,99例冠状动脉心脏病 (冠心病 )患者肾动脉狭窄的发生率为 19.2 % (19例 )。 8支狭窄肾动脉手术的技术成功率达 10 0 % ,随访 3～ 9个月 ,71.4 %的患者血压易于控制 ,其中 3例复查肾动脉造影未见再狭窄。结论　对冠脉有病变的高血压患者 ,在行冠脉造影的同时 ,有必要加做肾动脉造影 ,有助于肾动脉狭窄的早期诊断和治疗 ,避免发生肾功能衰竭。PTRA加支架术是目前治疗肾动脉狭窄的首选方法 ,具有安全、简便、有效的优点。     

Intracranial vascular stenosis and occlusion: MR angiographic findings.

PURPOSETo investigate whether obtaining axial source images from three-dimensional Fourier transform (3DFT) time-of-flight MR angiography improves the detection of intracranial vascular stenosis and occlusion if added to maximum-intensity projection (MIP) images.METHODSThe angiograms of 103 patients who had MR angiography for evaluation of possible intracranial vascular disease were reviewed retrospectively in a quantitative and nonquantitative fashion. Diameters of vessels on MR angiograms were measured quantitatively by two reviewers using a magnifying loupe and compared with the results from conventional angiograms. Degrees of stenoocclusive disease were categorized into five classes; an artery with stenosis of 50% or greater was considered to be diseased. Another five observers also reviewed the MIP images with and without source images in a blinded fashion by means of nonquantitative visual inspection.RESULTSIn all, 23 stenoocclusive lesions of 50% or greater were available for review. In the quantitative analysis, with MIP images alone, 14 (78%) of 18 moderate and severe stenoses and four (80%) of five occlusions were identified correctly. The addition of the source images increased the sensitivity to 100% for moderate and severe stenoses and to 100% for occluded vessels. In the visual inspection study, however, no statistically significant differences were found between interpretations of MIP images alone and those of MIP images in combination with source images.CONCLUSIONIn the quantitative study, interpretation of source images rather than MIP images reduced the tendency to overestimate stenosis seen with MR angiography and improved the sensitivity for detecting stenosis of 50% or greater. There was a discrepancy between the quantitative study and visual inspection. Experienced observers had a tendency to underestimate the degree of stenosis.     

经皮肾动脉支架置入治疗动脉粥样硬化性肾动脉狭窄后分肾功能的变化

目的：探讨经皮肾动脉支架置入（PTRAS）治疗动脉粥样硬化性肾动脉狭窄（ARAS）患者的临床效果。 方法：选取2013年1月1日-2015年12月31日在我院进行PTRAS手术的ARAS患者31例,均为单侧肾动脉狭窄。患者随访12个月,观察PTRAS的成功率,以及血压、降压药种类的变化;应用肾动态显像评估分肾肾小球滤过率（SKGFR）的变化。 结果：手术成功率100%,无手术严重并发症。术后3、6、12个月随访,患者的收缩压、舒张压、降压药种类较术前均明显降低,血肌酐较术前均无明显变化。术后3、6、12个月支架侧的SKGFR、总GFR较术前明显升高,而非支架侧SKGFR与术前无明显变化。将支架侧术前SKGFR的值以20 ml/min为界,将患者分为两组,SKGFR≥20 ml/min共15例,SKGFR< 20 ml/min共16例,分析两组术前、术后SKGFR的变化情况。研究结果显示对于术前SKGFR≥20 ml/min的患者：支架置入术前、术后3~12个月支架侧的SKGFR差异无统计学意义;对于术前SKGFR<20 ml/min的患者,术后3~12个月支架侧的SKGFR较术前均有增加,差异有统计学意义。 结论：PTRAS治疗ARAS手术成功率高,并发症低。支架侧的分肾功能明显改善,肾动脉狭窄侧的SKGFR越小,其术后肾功能改善的越明显。