Long-term follow-up after renal artery stenting

BACKGROUND: Renal artery stenosis may cause secondary arterial hypertension and lead to end-stage renal disease. Percutaneous transluminal angioplasty with stent implantation (PTRAS) allows effective and consistent treatment with a high technical success rate. The present trial focuses on the morphological and clinical results as assessed at a long-term follow-up (FU) visit. The main goals were assessment of the restenosis rate and evaluation of arterial hypertension and renal function. PATIENTS AND METHODS: 40 patients who had undergone successful stenting of a main renal artery were prospectively enrolled. At the FU visit, all patients underwent a risk-factor assessment, evaluation of arterial blood pressure and serum creatinine, and multi-detector computed tomography angiography (CTA). RESULTS: Median FU was 3.3 years. Hyperlipidemia was present in 67.5% of the patients, current cigarette smoking in 35% and diabetes mellitus in 15%. All patients still suffered from arterial hypertension but, compared with the pre-interventional situation, arterial hypertension was improved in 37.5%. Serum creatinine was increased in 25% of patients, mean creatinine level was 1.3 +/- 0.4 mg/dl. Hemodynamically relevant restenosis was detected by observer 1 in five patients and by observer 2 in six patients, giving restenosis rates of 12.5% and 15%, respectively, after the median FU period. Both observers detected three additional relevant stenoses in the contralateral main renal arteries. CONCLUSIONS: PTRAS gives excellent morphological long-term results. However, the clinical long-term outcome regarding arterial hypertension and renal function is only moderate.     

畸形肾血管体外重建在肾移植中的应用:2年随访结果

目的:供肾肾动脉常存在解剖学变异,应用这些血管畸形肾进行移植的临床效果尚无统一意见.观察体外重建畸形供肾血管对肾移植临床效果的影响.方法:选择解放军兰州军区总医院全军泌尿外科中心2006-06/2009-05行尸体供肾伴血管畸形患者27例为实验组,其中17例具有副肾动脉,另10例肾动脉为两三支畸形,均无法直接进行血管吻合.以同期进行正常尸体供肾肾移植患者22例作为对照组.体外血管重建的方法包括动脉端端吻合11例、端侧吻合6例、侧侧共干吻合6例、利用供体或受体髂动脉及其分支合并及延长供肾动脉4例.术后随访观察出血、新出现高血压(或高血压加重)、肾动脉狭窄、移植肾肾功能延迟恢复、急性排斥反应的发生率以及血肌酐水平.结果:移植后平均随访2年,两组患者49例均存活.实验组2例,对照组3例移植后出现高血压或高血压加重,两组间差异无显著性意义(P=0.673),但未发现移植肾动脉狭窄;实验组和对照组移植后肾功能延迟恢复发生率分别为20%和14%,急性排斥反应发生率分别为13%和5%,血肌酐水平分别为(119±11),(127±8) μmol/L,两组间差异均无显著性意义(P=0.179,0.385,0.658).结论:选择适当方法进行供肾畸形血管的重建不影响肾移植效果,可提高供体器官的利用率.     

Renal artery PTA and stent implantation: immediate and late clinical and morphological outcome

BACKGROUND: Renal artery stenosis (RAS) is a potentially curable cause of secondary hypertension, but the indications for interventional treatment of renovascular hypertension are still a matter of debate. The aim of the study was to investigate immediate and long-term results of percutaneous renal artery revascularization (PTRA). Primary technical success, peri-intervention complications, patency, the course of arterial hypertension and renal function were analyzed. METHODS: 32 renal interventions in 24 consecutive patients (15 PTA, 17 stents) were investigated in a retrospective cohort study. Comorbidities, interventional data and serum creatinine were recorded. Patients were followed for a median period of 45 months (IQR, 32 to 68). Clinical evaluation of the course of blood pressure, serum creatinine, Doppler ultrasound evaluation and multi-slice spiral-CT angiography were performed at follow-up. RESULTS: Primary technical success was achieved in 30 interventions (94%), and in 2 patients during a secondary intervention. The rate of complications was 16% (n = 5). Three major complications were encountered (9%): 1 renal artery thrombosis and 2 acute renal failures. Three patients developed late renal failure after 1, 4 and 37 months, but the overall serum creatinine levels remained stable during the observation period. Hypertension was improved after intervention in 17 patients (71%). However, recurrent hypertension was found in 9 patients (38%) after a median period of 49 months (IQR, 47 to 96). Patency rates at 12, 24 and 72 months were 94%, 94% and 64%, respectively. CONCLUSION: Renal artery PTA can be performed with an acceptable rate of major complications and good long term morphological results. However, clinical outcome in terms of sustained improvement of hypertension is moderate.     

肾血管性高血压对诱导型一氧化氮合酶表达及活性的影响

目的通过测定肾血管性高血压大鼠血管及肾组织诱导型一氧化氮合酶（iNOS）活性及表达的变化情况,探讨血压与iNOS间的关系。方法运用肾动脉不全结扎方法制备SD大鼠肾血管性高血压模型,并应用Greiss反应、L-精氨酸同位素标记法及Westernblot等分别测定一氧化氮的终产物——尿中NO     

Incidence of renal artery stenosis in a population having cardiac catheterization

Patients with renovascular hypertension comprise only a small percentage of those with hypertension. In our study 102 consecutive patients who had cardiac catheterization were screened at the time of the procedure for renal artery stenosis. Only 65 (64%) of the 102 patients were hypertensive, and 14 of the total population (13.7%) had renal artery stenosis. Of these 14 patients, only five had more than 50% narrowing of the arterial lumen. By renal vein renin determination, only four of the five patients with significant renal artery stenosis had lateralizing renins. The frequency of significant renovascular hypertension does not justify the routine search for this problem during catheterization procedures, though it may be worthwhile if the patients are hypertensive. This area deserves further evaluation.     

Renal artery stenosis: screening, diagnostic and therapeutic options

Hypertension is a frequent disease and renal artery stenosis, as a potential cause of hypertension, can be cured. Therefore, we frequently need to exclude a renal artery stenosis in patients with hypertension in our daily routine. This calls for a screening procedure which is non-invasive, highly effective and not too expensive. This paper describes the advantages and limitations of colour Doppler ultrasound in diagnosing renal artery stenosis. Colour Doppler ultrasound with intrarenal Doppler analysis is an ideal tool in the screening for relevant renal artery stenosis in patients with hypertension. This technique, however, requires a careful approach and extrarenal abnormalities need to be considered.     

Bilateral renal artery stenosis after abdominal radiotherapy for Hodgkin's disease

A 49-year-old woman was admitted with fatigue, dyspnoea, pretibial oedema and decreased daily urination. Seven years ago she was treated with doxorubicin, bleomycin, vinblastine and dacarbazine, alternating with mechlorethamine, vincristine, procarbazine and prednisone and 80 Gy abdominal radiotherapy for Hodgkin's disease. Two years later, malignant hypertension was diagnosed. Angiotensin-2 antagonist and beta-blocker treatment was given. After increased serum creatinine levels were determined, renal angiography was performed and total obstruction in the left renal artery and near total obstruction in the right side was observed. She was admitted to our clinic with oliguria, and acute renal failure was diagnosed. Balloon angioplasty and stent implantation was performed to the right renal artery. After a polyuric period, serum creatinine reduced to near normal levels. Angiotensin-2 antagonist treatment worsened the course in this patient. Patients with resistant hypertension occurring years after abdominal radiotherapy should be evaluated for renal artery stenosis.     

冠状动脉造影患者中肾动脉狭窄的相关研究

目的在进行冠状动脉造影的患者中同时进行肾动脉造影,观察肾动脉狭窄的发生率及相关因素研究。方法200例冠状动脉造影患者全部行选择性双侧肾动脉造影,对临床资料和肾动脉狭窄之间的关系进行单变量分析。结果肾动脉狭窄者27例,占13.5%,其中轻度狭窄者（〈50%）13例,占6.5%,明显狭窄者14例,占7.0%。明显肾动脉狭窄单变量分析,年龄、吸烟、高血压、糖尿病、颈动脉斑块形成、严重冠状动脉病变是肾动脉狭窄的影响因素。结论在冠状动脉造影尤其冠心病患者中,肾动脉狭窄发生率高,多见于老年合并高血压、严重冠状动脉病变患者,在冠心病患者行冠状动脉造影的同时应常规进行肾动脉造影,以便及早发现肾动脉狭窄。     

Effect of enalapril on renin, angiotensin converting enzyme activity, aldosterone and prostaglandins in patients with hypertension

Enalapril (MK-421) was administered orally as a single dose of 2.5, 5.0, 10 and 20 mg to 13 patients with either essential or renovascular hypertension. At these doses, enalapril produced a moderate reduction in both supine and standing blood pressure as well as a significant reduction in angiotensin I-converting enzyme activity, an increase in peripheral plasma renin activity and a decrease in plasma aldosterone concentration 4 to 8 hours after administration of the drug. Plasma levels of prostaglandins E1 and E2 were unchanged. The calculated ratio of urinary Na/K was increased in the patients with renal artery stenosis after enalapril. Creatinine clearance was increased in the patients with essential hypertension and reduced in the patients with renal artery stenosis. No adverse effects occurred in these patients treated with single doses of enalapril.     

Atherosclerotic Renovascular Disease

The patient, a 78-year-old Asian male, was brought to the hospital because of acute shortness of breath that had progressively worsened over the course of the day. He complained of a nonproductive cough and claudication after walking 1 block. His past medical history was significant for mild renal insufficiency (serum creatinine 1.5--2.0 mg/dl), the etiology of which was never explored. Although there was a recent history of mild to moderate hypertension, at presentation his blood pressure was noted to be 240/118 mm Hg in both arms. His physical exam at the time of admission was remarkable for grade II hypertensive retinopathy, an S4 gallop, periumbilical systolic bruits, audible femoral arterial bruits and absent distal lower extremity pulses. Initial complete blood count, serum electrolytes and cardiac enzymes (including lactate dehydrogenase) were normal. His blood urea nitrogen and serum creatinine concentrations were 51 and 3.6 mg/dl, respectively, and his urinalysis showed 1+ protein (both by dipstick and sulfasalicylic acid) with a "benign" sediment (0--1 WBC/HPE, 1--2 RBCs/HPF) with occasional granular casts. His electrocardiogram, apart from demonstrating left ventricular hypertrophy with secondary ST-T wave abnormalities, showed no acute changes; his chest X-ray demonstrated cardiomegaly and pulmonary vascular congestion. He was intubated and subsequently treated with increasing parenteral doses of furosemide (40--240 mg) and a nitroglycerine drip (up to 15 mcg/min). Over the course of the first 48 h, his blood pressure was gradually lowered to 170/100 mm Hg. His urine output increased from 20 ml/h to 125/ml/h, and his respiratory status improved, allowing him to be extubated. In spite of adequate control of his blood pressure in the ensuing days (150--170/80--90 mm Hg), his renal function continued to deteriorate. Renal sonography (without Doppler) demonstrated a right kidney of 9.6 cm and a left kidney of 9.3 cm in length without evidence of hydronephrosis. Both kidneys were noted to be echogenic. Assays for antinuclear antibodies and antineutrophilic cytoplasmic antibodies were negative, and the patient's serum complement levels were normal. For several days after his admission, his serum creatinine gradually rose to 10.7 mg/dl, and hemodialysis was initiated for uremic encephalopathy. Because of the high index of suspicion for renal artery stenosis as the case of both his hypertension and renal failure, a renal angiogram was performed. It revealed a 90% occlusion of the right renal artery with ostial involvement and a 70% occlusion of the left renal artery; both kidneys had poor distal renal vasculature and there was marked atherosclerotic disease of the aorta. After being hemodialyzed for 3 treatments, his renal function began to improve spontaneously. His serum creatinine returned to 3.4 mg/dl, and a subsequent 24-hour urine demonstrated a creatinine clearance of 20 ml/min and an excretion of 1.2 g of protein. Following his discharge from the hospital, his renal function remained unchanged for 3 years, and his blood pressure was easily controlled on monotherapy with a long-acting calcium channel blocker. He recently died from pneumonia.     

Vascular complications in the adult kidney transplant recipient.

Vascular complications of renal transplantation occurred in 15% of the cases. They are thrombotic infarct, arterial stenosis, arterio-venous fistula, and chronic arterial diseases. From 900 renal transplantations performed, only 120 (made since 1989) were studied with color flow Doppler (CFD). Lack of arterial signal is indicative of main arterial thrombosis (or of renal infarct if thrombosis is limited). At the site of arterial stenosis, high velocity and turbulence are found. If the stenosis is more than 70%, the rising systolic time is longer than 0.07 sec in the post-stenotic artery. Arterio-venous fistulas are frequent after renal biopsy. They provoke vibrations transmitted to peri-vascular tissues and seen with CFD as a large area of turbulence. In the feeding artery, Fast Fourier Transformation (FFT) showed a high velocity with a low resistive index and pulsed flow in the outgoing vein. Chronic arterial diseases include cyclosporine A intoxication and chronic rejection. These two diseases cannot be diagnosed by CFD alone.     

肾移植后血管并发症介入治疗8例

背景:肾移植后血管并发症采用介入治疗已成为一种安全有效的治疗方法。目的:探讨肾移植后血管并发症介入治疗的经验及价值评估。方法:回顾性分析8例肾移植后血管并发症患者介入治疗的临床资料。结果与结论:8例移植后5例肾移植肾动脉狭窄,2例假性动脉瘤,1例肾静脉血栓,均经彩色多普勒血流显像作出初步诊断,其中5例进一步行磁共振血管成像明确诊断。5例移植肾动脉狭窄行球囊扩张,分别随访6,8,20,36,40个月,1例出现再狭窄,随访血肌酐维持在130~160μmol/L之间,其余4例移植肾狭窄无复发,随访血肌酐均正常。2例假性动脉瘤患者经动脉鞘放入支架释放系统释放带膜支架后动脉瘤消失,目前常规血液透析治疗。1例肾静脉血栓形成患者,尿激酶介入溶栓治疗后血栓消失,患者发生移植肾功能延迟恢复,35d后血肌酐降至210μmol/L,此后患者血肌酐维持在200～250μmol/L。8例介入治疗临床效果说明肾移植后血管并发症治疗可选用介入治疗方法。     

Renovascular hypertension: can we identify a population at high risk?

Renovascular hypertension is a common cause of secondary hypertension. However, diagnostic tests are limited by lack of sensitivity and specificity, cost, or invasiveness. Selecting patients with hypertension for evaluation of renal artery stenosis can be challenging. This review focuses on the sensitivity and specificity of commonly used screening tests for renal artery stenosis and on the clinical variables that are most likely to distinguish patients with renal artery stenosis from patients with other causes of their hypertension. This approach allows for the rational screening of patients at high and moderate risk for renal artery disease.     

炎性肾动脉狭窄的外科治疗分析:附31例报告

目的:探讨炎性肾动脉狭窄的临床特点以及外科治疗方法的选择和疗效。方法:回顾分析1998年6月—2013年11月收治的31例行外科治疗的炎性肾动脉狭窄患者的临床资料。31例患者共接受外科治疗33例次,其中手术治疗17例次,包括腹主动脉肾动脉旁路术10例次,自体肾移植术5例次,肾切除2例次;腔内治疗16例次,包括球囊扩张术9例次(其中切割球囊术2例),支架成形术7例次(其中药物涂层支架1例)。结果;31例患者围手术期病死1例,其余30例患者中有23例获得随访,平均随访时间(41.8±35.7)个月,随访期内无病死病例。23例患者的随访显示,患者血压[(135.7±16.3)mmHg/(85.5±10.6)mmHg]较术前[(1 59.6±19.4)mmHg/(96.3±16.7)mmHg]显著下降(P0.01);治愈3例,好转16例,降血压的有效率为82.6%;23例患者的血肌酐水平与术前比较差异无统计学意义。彩超随访显示,传统手术治疗的患者中有3例发生吻合口轻度再狭窄,而腔内治疗的患者中有4例发生中度再狭窄甚至闭塞。结论:炎性肾动脉狭窄多见于年轻患者,主要表现为顽固性高血压;外科治疗控制血压的效果确切,传统手术疗效优于腔内治疗。     

A refractory hypertensive patient with fibromuscular dysplasia and multicystic dysplastic kidney

The case of a 16-year-old male patient with left renal artery stenosis due to fibromuscular dysplasia (FMD) and an atrophic kidney due to a right multicystic dysplastic kidney (MCDK) who presented with refractory hypertension is reported. On continuous Doppler imaging, the peak systolic velocity (PSV) at the stenotic site of the left renal artery was 404 cm/s. The FMD formed a “string-of-beads” appearance on computed tomographic angiography (CTA) and renal artery angiography. Percutaneous transluminal renal angioplasty (PTRA) with a balloon catheter was performed, after which the left renal artery returned to near normal, and his blood pressure decreased to within the normal range. In this case, the main cause of refractory hypertension was considered to have been renal artery stenosis due to left FMD.     

Influence of resting before sonographic examination on Doppler measurements of renal blood flow

Renal artery stenosis (RAS) is the most common cause of secondary hypertension, via increases in plasma renin–angiotensin–aldosterone levels. Renal artery stenosis is diagnosed from blood examinations such as renin activity and from imaging examinations such as sonography. Patients are required to lie on the bed for 30 min before and during phlebotomy, since plasma renin activity is easily altered by posture. However, no such pre‐examination rest is required for sonography. The present study therefore investigated the possible influence of resting before examination on Doppler parameters used for the diagnosis of RAS. Subjects comprised 55 healthy young adults (24 males, 31 females; mean age, 22 ± 1 years). Sonographic measurements were made shortly after subjects entered the examination room and again after 30 min of rest lying on a bed. Median peak systolic velocity in the renal artery was significantly decreased after rest (106 cm/s, interquartile range (IQR) 96–121 cm/s) compared with before rest (120 cm/s, IQR 107–135 cm/s; p < .001). Median acceleration time in the intra‐renal segmental artery was also significantly shorter after rest (49 ms, IQR 38–54 ms) compared to before rest (50 ms, IQR 38–59 ms; p = .039). The present results suggest that serious consideration should be given regarding whether pre‐examination resting is needed to accurately interpret Doppler measurements of renal blood flow when diagnosing RAS from sonography.     

Endovascular treatment for renal artery stenosis

Atherosclerosis accounts for 90% of the cases of renal artery stenosis. It is an important cause of secondary arterial hypertension by means of inducing the renin-angiotensin system, volume expansion, and sympathetic activation. Despite high procedural success rate of renal artery stenting, clinical trials have shown an inconsistent outcome about improvement in hypertension. The accurate predictors identify the good indication for renal artery stenting is clinically needed. Currently, the presence of hemodynamically critical stenosis causing renal ischemia, the presence of symptoms with undoubtedly benefit from revascularization, and the assessment of procedural risk are key factors for decision making about indication of renal artery stenting.     

A case of early onset normotensive scleroderma renal crisis in a patient with diffuse cutaneous systemic sclerosis

Scleroderma renal crisis (SRC) has classically been defined as a new onset of accelerated arterial hypertension associated with a rapid increase in serum creatinine concentration and/or microangiopathic hemolytic anemia. SRC occurs in approximately 20% of patients with systemic sclerosis who have diffuse cutaneous manifestations. In addition, 10% of reported cases of SRC with diffuse cutaneous involvement have normal blood pressures; in the majority of these cases, SRC occurs after treatment with corticosteroids. We describe a patient who presented with an early onset SRC in the setting of diffuse cutaneous systemic sclerosis in evolution without prior accelerated arterial hypertension or corticosteroid use.     

Malpractice in Invasive Cardiology: Is Angiography of Abdominal Aorta or Subclavian Artery Appropriate in Patients Undergoing Coronary Angiography?

Background: Identification of peripheral vascular disease by angiography in patients undergoing coronary angiography may be considered as malpractice but sometimes seems to be justified under clear entry criteria. The present mata-analysis is aimed to analyze the appropriateness and results of screening angiography of subclavian or abdominal aorta performed at the time of coronary angiography. Methods: A search of published literature for peripheral angiography in patients undergoing coronary angiography over the last 10 years was performed using the MEDLINE database. No language restriction was employed. Only studies enrolling more than 100 patients for abdominal aortography and 50 patients for subclavian/internal mammary artery angiography were considered. Reference lists from identified studies were also reviewed to identify other potentially relevant references. Results: Twenty-nine studies were retrieved: 8 articles about subclavian artery (SA) and internal mammary (IMA) angiography and 21 about renal (RA) and aortoiliac (AOI) angiography. The total number of patients enrolled was 27,936. Nine studies out of 29 were prospective. Defined entry criteria were reported in 24 out of 29 studies. Significant SA and IMA stenosis were reported in 5.5 and 9% of patients, respectively. RA stenosis >50% was present in 12.7% of patients with CAD. Finally, undetected AOI disease was reported in 35.5% of patients undergoing coronary angiography. Mean complication rate was 0.8 ± 0.6%. Predictors of SA and IMA stenosis were unclear. Age, multi-risk profile, multi-vessel CAD, history of PVD or carotid disease, severe hypertension, unexplained renal dysfunction or decreased creatinine clearance have been reported most frequently as predictors of RA and AOI disease in patients undergoing coronary angiography. Conclusions: Consistent evidence of appropriateness of renal angiography in selected patients undergoing coronary angiography have been produced in literature. IMA and AOI angiography seem to be not justified unless they are part of SA in patients scheduled for arterial conduit with brachial differential pressure, thoracic irradiation or surgery, or of abdominal angiography to detect RA stenosis in laboratories with radiological digital peripheral equipment.     

原发性高血压合并冠心病患者脂蛋白(a)的变化

目的 探讨原发性高血压(EH)合并冠心病患者血清脂蛋白(a)[Lp(a)]水平的变化及其临床意义.方法 选择老年EH患者159例,根据冠状动脉造影结果分为单纯EH组73例和合并冠心病组86例,检测其空腹血糖、肌酐、总胆固醇、甘油三酯、LP(a)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C),计算体重指数.结果 与单纯EH组相比,Lp(a)水平在EH合并冠心病组明显增高[(0.34±0.12)、(0.48±0.18)mmol/L,t=-11.367,P＜0.05],在EH合并冠心病组中随冠状动脉病变程度的加重Lp(a)水平呈增高趋势[单支、双支、多支及弥漫病变组分别为(0.34±0.14)、(0.46±0.15)、(0.66±0.12)mmol/L,F=31.842,P=0.012].结论 EH患者Lp(a)水平与冠心病的发生及其严重程度相关.Lp(a)作为冠心病的危险因素,可以预测冠状动脉病变的严重程度.

Abstract：

Objective To study the changes of lipoprotein(a)[LP(a)] in patients with essential hypertension(EH) and coronary heart disease(CHD).Methods One hundred and fifty-nine EH older patients were recruited in the study.Eighty-six elderly patients were diagnosed as EH combined with CHD,and 73 patients were diagnosed as simple EH.All patients were tested for the fasting blood glucose(FBG),creatinine(Cr),total cholesterol(TC),triglyceride(TG),HDL-C,LDL-C,LP(a),and the body mass index(BMI) was calculated.Results Plasma Lp(a) increased(0.48±0.18)mmol/L in the EH combined with CHD patients,which were significantly higher than the increasing of(0.34±0.12) mmol/L in the simple EH patients(t=-11.367,P＜0.05).The level of plasma Lp(a) increased with the severity of the stenosis of the coronary artery(Lp(a):(0.37±0.14) mmol/L in single arterial branch stenoses,(0.46±0.15)mmol/L in double arterial branch stenoses,(0.66±0.12)mmol/L in triangle arterial branch stenoses,F=31.842,P=0.012).Conclusion The Lp(a) concentration in patients with EH are correlated with the occurrence and severity of coronary heart disease.As a risk of coronary heart disease,Lp(a) can predict the severity of coronary artery stenosis.