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OBJECTIVE: Percutaneous transluminal renal angioplasty (PTRA) has been used to treat renovascular disease (RVD), a chronic condition characterized by renal ischemia and metabolic abnormalities. Mitochondrial injury has been implicated as a central pathogenic mechanism in RVD, but whether it can be reversed by PTRA remains uncertain. We hypothesized that PTRA attenuates mitochondrial damage, renal injury and dysfunction in pigs with coexisting renal artery stenosis (RAS) and metabolic syndrome (MetS). METHODS: Four groups of pigs (n=6 each) were studied after 16 weeks of diet-induced MetS and RAS (MetS+RAS), MetS+RAS treated 4 weeks earlier with PTRA, and Lean and MetS Sham controls. Single-kidney renal blood flow (RBF) and glomerular filtration rate (GFR) were assessed in-vivo with multi-detector-CT, and renal tubular mitochondrial structure and function and renal injury ex-vivo. RESULTS: PTRA successfully restored renal artery patency, but mean arterial pressure remained unchanged. Stenotic kidney RBF and GFR, that fell in MetS+RAS compared to MetS, rose after PTRA. PTRA attenuated MetS+RAS-induced mitochondrial structural abnormalities in tubular cells and peritubular capillary endothelial cells, decreased mitochondrial H(2)0(2) production, and increased renal cytochrome-c oxidase-IV activity and ATP production. PTRA also improved cortical microvascular and peritubular capillary density and ameliorated tubular injury and tubulointerstitial fibrosis in the post-stenotic kidney. Importantly, renal mitochondrial damage correlated with post-stenotic injury and dysfunction. CONCLUSION: Renal revascularization attenuated mitochondrial injury and improved renal hemodynamics and function in swine post-stenotic kidneys. This study suggests a novel mechanism by which PTRA might be relatively effective in ameliorating mitochondrial damage and improving renal function in coexisting MetS and RAS.

Effective therapeutic strategies are needed to preserve renal function in patients with atherosclerotic renal artery stenosis (ARAS). Low-energy shockwave therapy (SW) and adipose tissue-derived mesenchymal stem/stromal cells (MSCs) both stimulate angiogenesis repair of stenotic kidney injury. This study tested the hypothesis that intrarenal delivery of adipose tissue-derived MSCs would enhance the capability of SW to preserve stenotic kidney function and structure. Twenty-two pigs were studied after 16 weeks of ARAS, ARAS treated with a SW regimen (bi-weekly for 3 weeks) with or without subsequent intrarenal delivery of adipose tissue-derived MSCs and controls. Four weeks after treatment, single-kidney renal blood flow (RBF) before and after infusion of acetylcholine, glomerular filtration rate (GFR), and oxygenation were assessed in vivo and the renal microcirculation, fibrosis, and oxidative stress ex vivo. Mean arterial pressure remained higher in ARAS, ARAS + SW, and ARAS + SW + MSC compared with normal. Both SW and SW + MSC similarly elevated the decreased stenotic kidney GFR and RBF observed in ARAS to normal levels. Yet, SW + MSC significantly improved RBF response to acetylcholine in ARAS, and attenuated capillary loss and oxidative stress more than SW alone. Density of larger microvessels was similarly increased by both interventions. Therefore, although significant changes in functional outcomes were not observed in a short period of time, adjunct MSCs enhanced pro-angiogenic effect of SW to improve renal microvascular outcomes, suggesting this as an effective stratege for long-term management of renovascular disease.

The time trends regarding the etiology of renal artery stenosis (RAS) are changing, but few investigations have focused on these issues. This study aimed to analyze the time trends regarding the etiology of RAS in a large patient sample from the China Center for Cardiovascular Disease. Consecutive inpatients with RAS from January 1999 to December 2016 were enrolled in this study. The etiologic diagnosis of RAS was based on established criteria. We retrospectively analyzed the time trends regarding the etiology of RAS during an 18-year period. A total of 2905 patients with RAS were enrolled. There were 2393 (82.4%) patients with atherosclerosis (AS), 345 (11.9%) with Takayasu arteritis (TA), 126 (4.3%) with fibromuscular dysplasia (FMD), and 41 (1.4%) with other causes. Among all patients (n = 2905), patients aged ≤ 40 years (n = 450), patients aged40 years (n = 2455), female patients (n = 1097), male patients (n = 1808), female patients aged40 years (n = 808), and male patients aged40 years (n = 1647), there were a gradual increase in the proportion of atherosclerotic RAS (P 0.05), a gradual decrease in the proportion of RAS caused by TA (P 0.05), and almost no change in the proportion of RAS caused by FMD during the 18-year period (P 0.05). The data show that the primary causes of RAS are AS, TA, and FMD. The proportion of RAS caused by AS and TA gradually increased and decreased, respectively, over time, and the proportion of RAS caused by FMD showed no significant change.

The authors evaluated the effectiveness of percutaneous renal revascularization (PRR) with stenting for the treatment of atherosclerotic renal artery stenosis (ARAS) in patients with coronary artery disease and the usefulness of captopril renal scintigraphy for predicting clinical outcomes after PRR. Sixty‐four consecutive patients, referred for evaluation of suspected ARAS, after coronary angiography, underwent baseline captopril renal scintigraphy followed by renal angiography. Forty‐four patients (68.7%) were diagnosed with a significant ARAS≥ 60% and were treated with PRR plus medical therapy. Twenty‐four months after PRR, 86.4% and 73.3% of patients showed a hypertension and renal benefit, respectively. Captopril renal scintigraphy positivity had moderate sensitivity and high specificity in predicting a hypertension and renal benefit. In patients with ARAS≥ 70%, the sensitivity and specificity were 100% for both a hypertension and renal benefit. PRR for ARAS conferred a substantial benefit in patients with a high coronary artery disease burden. Captopril renal scintigraphy was highly accurate in predicting clinical outcomes.

Renal artery stenosis (RAS) is a prevalent cause of secondary hypertension. Elderly patients with atherosclerosis and young women with fibromuscular dysplasia (FMD) are particularly at risk. Blood pressure screening is often key to this diagnosis, although the reliability of clinical screening has been questioned, and ambulatory blood pressure monitoring (ABPM) likely offers superior ability to diagnose poorly controlled hypertension. In patients with RAS, medical management should be the primary means of therapy; however, in a select group of these patients, renal revascularization may be considered, and has been shown to reduce blood pressure and stabilize chronic kidney disease. In this report, we present a patient diagnosed with RAS due to FMD, found to have significant hypertension via ABPM, and treated successfully with percutaneous renal artery angioplasty; importantly, continuous 24-hr ambulatory monitoring after pressure gradient guided renal angioplasty confirmed reduction in blood pressure.

Renovascular stenosis is an important cause for arterial hypertension in childhood. We report a 10-month-old girl with arterial hypertension caused by right-sided renal artery stenosis detected by Doppler ultrasound. Magnetic resonance imaging (MRI) was performed before renal artery angioplasty to depict vascular anatomy in detail and to retrieve additional functional information of the kidneys by analysis of intravoxel incoherent motion (IVIM). The value of quantitative diffusion weighted imaging of the kidneys prior to percutaneous transluminal renal angioplasty (PTRA) is discussed.

BACKGROUND: Renal fibromuscular dysplasia (FMD) is typically diagnosed in young hypertensive women. The 2014 European FMD Consensus recommended screening in all hypertensive women

Renal artery stenosis can be diagnosed during pregnancy and treated at the same time. A 30-year-old woman had a sudden, severe but asymptomatic hypertensive crisis at 21 weeks of gestation. The diagnosis of renal artery stenosis suspected on Doppler ultrasonography was confirmed and treated by renal angioplasty, which reduced her blood pressure. At 27 weeks of gestation, her blood pressure increased again, associated with significant proteinuria, suggesting pre-eclampsia. A cesarean section was performed giving birth to a healthy 940-g child. Renal artery stenosis should be considered when sudden and early-onset hypertension appears during pregnancy.

ObjectiveTo describe and standardize an original protocol for fractional flow reserve (FFR) pre and postangioplasty in an initial series of patients with clinically manifested transplant renal artery stenosis (TRAS). BackgroundThere is no data in the literature about the use of FFR in TRAS. MethodsPatients with TRAS detected in a noninvasive study were referred to diagnostic angiography and stenosis considered visually severe ( 60%) were included. After selective cannulation, a PressureWire 0.014 (CertusSt. Jude Medical) was advanced to the distal portion of the vessel. Resting Pd/Pa ratio (ratio of mean distal to lesion and mean proximal pressures) and translesional systolic pressure gradient were obtained and FFR and hyperemic translesional systolic and mean pressure gradients (HSG and HMG) were registered after papaverine induced maximum hyperemiapre and poststent implantation. Creatinine levels and office blood pressure measurements were registered at the baseline, 6 and 12months after intervention. ResultsTen consecutive patients had successful stent implantation and were included. After treatment, significant increase in FFR (0.760.09 vs. 0.96 +/- 0.04, P

Aim This studied reviewed renovascular hypertension (RVH) due to renal artery stenosis (RAS) in two Serbian paediatric centres from 2001 to 2013. Methods The patients' demographic data, underlying syndromes, blood pressure (BP), antihypertensive treatments and outcomes were reviewed. Results The incidence of RVH was 1.9 per million children per year during the study period, and there were 25 patients with RAS, aged 10.4 ± 5.2 years. At presentation, their mean blood pressure (BP) standard deviation scores were 6.9 ± 3.4 systolic and 5.2 ± 2.6 diastolic. BP loads on 24-hour ambulatory BP were 88 ± 14% systolic and 80 ± 29% diastolic. We found that 72% had fibromuscular dysplasia and 28% had underlying syndromes. RAS was unilateral in 64% and bilateral in 28%, and 8% had RAS of a single kidney. Antihypertensive treatment included antihypertensive drugs (100%), percutaneous transluminal angioplasty (92%), renal auto-transplantation (16%), surgical revascularisation (12%) and nephrectomy (12%). After 4.4 ± 3.6 years of follow-up, high BP was cured in 40% of the patients and 39.4% of the kidneys and improved in 48% (75.7%), with BP decreases of 20.3 ± 3.7% systolic and 16.3 ± 6.2% diastolic. Conclusion Fibromuscular dysplasia was the most common cause of RVH in this study, and hypertension was cured or improved in 88% of the patients.

A 55-year-old woman with newly diagnosed Takayasu arteritis was followed for 7 years, during which time she underwent bare metal stenting, drug eluting stenting and coronary bypass grafting for critical coronary and renal artery stenoses. Interventions were initially successful but restenosis occurred within 24 months for all modalities. In contrast, native vessel disease was largely stable after the introduction of immunosuppressive therapy. We advocate a conservative revascularization approach in Takayasu arteritis in the absence of critical end organ ischemia and early optimization of medical therapy.

The authors describe the clinical investigation and progress of a 13-year-old girl diagnosed with hypertension 4 years prior to her admission. A thorough history was taken and physical examination performed. Laboratory analysis and relevant radiological evaluation were obtained in order to determine the etiology for suspected secondary hypertension, and later to differentiate between the possible causes of hyperreninemic hypertension. The patient had an accessory left renal artery, presumptively leading to renin secretion by the underperfused kidney. The patient was treated medically with spontaneous resolution of her hypertension and near normalization of plasma renin activity. On repeat imaging, the artery was not demonstrated. The authors concluded that the diagnosis of hyperreninemic hypertension in young ages should prompt investigation for the etiology. However, cautious observation is a valid option that might lead to spontaneous resolution.

This study aimed to define the difference in cardiac hypertrophy between hypertensive patients with and without renal artery stenosis (RAS). When cardiac ultrasonographic examination was performed in 971 consecutive hypertensive outpatients, renal peak systolic velocity (PSV) was examined. Compared with patients without RAS, those with RAS (PSV ≥180 cm/s, 4.1%) were significantly older and included a higher proportion of male patients and had a higher left ventricular mass index (LVMI). A stratified analysis in the selected 120 patients showed that the LVMI was significantly higher in patients with RAS than in those without RAS for each confounding factor such as age and blood pressure. RAS was independently associated with a higher LVMI on propensity score analysis and multivariate analysis. Thus, the difference in LVMI between hypertensive patients with and without RAS was confirmed, irrespective of age and blood pressure, by stratified propensity score analysis and multivariate regression analysis.

The Safety and Effectiveness Study of the Herculink Elite Renal Stent to Treat Renal Artery Stenosis (HERCULES) trial is a prospective, multicenter trial evaluating the safety, effectiveness, and durability of the RX Herculink Elite renal stent system (Abbott Vascular, Abbott Park, IL) in select patients with atherosclerotic renal artery stenosis and uncontrolled hypertension. A total of 202 patients were enrolled between August 2007 and October 2009. The primary endpoint, 9-month binary restenosis, was 10.5% determined by core laboratory adjudicated duplex ultrasound and/or angiography. Additional analyses included changes in blood pressure, antihypertensive medications, renal function (RF), major adverse events (MAEs) (death, ipsilateral nephrectomy, and embolic events resulting in kidney damage), and clinically driven target lesion revascularization (CD-TLR) between baseline and 36 months. Freedom from MAE was 98.5% at 30 days. At 36 months, freedom from death, nephrectomy, and CD-TLR were 90.1%, 100%, and 91.8%, respectively. After 30 days there were no site-reported embolic events resulting in kidney damage. The mean baseline systolic blood pressure of 162±18 mm Hg significantly decreased postprocedure and through 36 months (mean systolic blood pressure 141 mm Hg [P

BACKGROUND AND OBJECTIVE Results of interventional trials in renovascular hypertension have been disappointing, and medical therapy is the current recommended gold standard. However, the comparative long-term benefits of different antihypertensive drug classes in atherosclerotic renal artery stenosis are not known. We aim to assess the effect of different antihypertensive drug classes on outcomes in renovascular hypertension DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS: Using Tayside Health Informatics Centre database, anonymized data over a 6-year period was analyzed. Biochemistry, prescribing data, morbidity, mortality, and demographic data were accessed via hospital medical records and electronic data stored in the Tayside Health Informatics Centre Safe Haven. General Registrar's Office data were used to identify patients who died from cardiovascular disease. Independent predictors of survival in each group were analyzed using Kaplan-Meier survival curves and Cox proportional hazard models, adjusted for a range of covariates, using time-updated drug analysis. Blood pressure data were obtained from primary and secondary care clinic blood pressure records for each patient. Adjustments for mean systolic blood pressure over the follow-up period and baseline blood pressure were made. RESULTS A total of 579 patients with atherosclerotic renal artery stenosis were identified. In the unilateral renal artery stenosis cohort, calcium channel blockers but not ACE inhibitors/ARBs were associated with a significant reduction in all-cause (HR = 0.45, CI = 0.31, 0.65; P =

Renal artery stenosis (RAS) due to atherosclerosis continues to be a major cause of secondary hypertension. It can also lead to renal dysfunction due to ischemic nephropathy. While major clinical trials have emphasized that medical management should be preferred over angioplasty and stenting for the treatment of renal artery stenosis, clinical scenarios continue to raise doubts about the optimal management strategy. Herein, we present two cases that were admitted with hypertensive emergency and renal function deterioration. Medical therapy failed to control the blood pressure and in one patient, renal failure progressed to a point where renal replacement therapy was required. Both patients underwent angioplasty (for >90% stenosis) and stent insertion with successful resolution of stenosis by interventional radiology. Postoperatively, blood pressure gradually decreased with improvement in serum creatinine. Dialysis therapy was discontinued. At 4- and 8-month follow-up, both patients continue to do well with blood pressure readings in the 132-145/70-90 mmHg range. This article highlights the importance of percutaneous interventions in the management of atherosclerotic RAS and calls for heightened awareness and careful identification of candidates who would benefit from angioplasty and stent insertion.

Atherosclerotic renal artery stenosis, a fairly common disease of older persons, is a manifestation of generalized atherosclerosis, and is often associated with coronary artery disease. It is frequently associated with hypertension and impaired renal function, and is perceived by many physicians to be the cause of hypertension and renal failure. For this reason, they believe that hypertension can be cured by performing percutaneous renal artery angioplasty (PTRA) with stent placement. This practice has led to an increase in angioplasties, especially by interventional cardiologists, although the results from several randomized studies comparing interventional therapy with medical therapy have shown no significant difference between the two treatment modalities in blood pressure reduction or change in renal function. Similar results have been found by nonrandomized trials with selective PTRA. For this review, a Medline search of the English literature was conducted from 2006 to 2012, and 13 pertinent studies were selected. These studies with collateral literature will be discussed in this concise review.

Hypertension is one of the major complications in neurofibromatosis type 1 (NF1). It is known to be caused by renal artery stenosis or pheochromocytoma. However, more than half of hypertensive patients with NF1 do not have either disorder. We report here on a 13-year-old male with NF1 who had hypertension and a stenosis of the right renal artery associated with elevated renal vein renin on the diseased side. He underwent percutaneous transluminal renal angioplasty. In spite of successful dilation of the artery and normalized renin level, high blood pressure persisted beyond 6 months requiring antihypertensive medication. His wide pulse pressure suggested arterial stiffness due to NF1 vasculopathy. We posit that the cause of hypertension in this patient was considered to be arterial stiffness ascribed to NF1 vasculopathy rather than renal artery stenosis. Increased pulse pressure supports the hypothesis. This marker of arterial stiffness can be assessed non-invasively and should be evaluated routinely in NF1. © 2013 Wiley Periodicals, Inc.

Introduction Non-invasive imaging studies can provide visualization of allograft perfusion in the postoperative evaluation of newly transplanted renal allografts. Aim The purpose of our study was to evaluate the significance of elevated renal artery velocities in the immediate postoperative period. Methods Peak systolic velocities (PSVs) were obtained in the transplanted renal artery of 128 patients immediately after transplantation. Repeat allograft Doppler ultrasonography was performed on patients with elevated values. Results Of the 128 patients, 57 (44.5%) had severely elevated Doppler velocities >400 cm/s on the initial studies. Three patients within this category had persistently elevated values of >400 cm/s, warranting angiographic visualization of the renal vessels. Stent placement within the transplanted renal artery was required in two of these patients. There was normalization of the PSV in the remaining patients. Conclusions Routine allograft Doppler ultrasonography in the immediate postoperative period allows for visualization of allograft perfusion. Elevated renal artery velocities in the immediate postoperative period do not necessarily represent stenosis requiring intervention. Failure of the PSV to normalize may require further intervention, and angiography continues to be the gold standard.

Authors have proposed new methodology in recent years for evaluating the improvement in prediction performance gained by adding a new predictor, Y, to a risk model containing a set of baseline predictors, X, for a binary outcome D. We prove theoretically that null hypotheses concerning no improvement in performance are equivalent to the simple null hypothesis that Y is not a risk factor when controlling for X, H0 : P(D = 1 | X,Y ) = P(D = 1 | X). Therefore, testing for improvement in prediction performance is redundant if Y has already been shown to be a risk factor. We also investigate properties of tests through simulation studies, focusing on the change in the area under the ROC curve (AUC). An unexpected finding is that standard testing procedures that do not adjust for variability in estimated regression coefficients are extremely conservative. This may explain why the AUC is widely considered insensitive to improvements in prediction performance and suggests that the problem of insensitivity has to do with use of invalid procedures for inference rather than with the measure itself. To avoid redundant testing and use of potentially problematic methods for inference, we recommend that hypothesis testing for no improvement be limited to evaluation of Y as a risk factor, for which methods are well developed and widely available. Analyses of measures of prediction performance should focus on estimation rather than on testing for no improvement in performance. Copyright © 2013 John Wiley & Sons, Ltd.

Aim To describe the frequency of renovascular abnormalities and hypertension in an opportunistic cohort of children with complex cerebrovascular disease from a single tertiary/quaternary referral centre. Method This was a retrospective case note and imaging review of children who had had cerebral and renal angiography, with a diagnosis of moyamoya or other occlusive cerebrovascular disease (OCVD). Hypertension was defined as at least three systolic blood pressure readings of the 95th centile or above. Results Of 34 children (12 males, 22 females; median age 5y 11mo, range 2mo-15y 3mo; 20 with moyamoya, 14 with OCVD), primary presentation was neurological in 29 (arterial ischaemic stroke, transient ischaemic attack, or headache) and with hypertension in five. Renovascular abnormalities were identified in 17, of whom 10 had main renal artery stenosis. Renovascular involvement was not predictable according to arteriopathy diagnosis. Blood pressure was rarely plotted on centile charts. Using the 50th height centile for blood pressure, and based on a median of five systolic blood pressure readings per patient, 20 out of 34 met the definition for hypertension (15/29 patients with primary neurological presentation). Interpretation Renovascular abnormalities were common in this group of children with complex cerebrovascular disease. Blood pressure was frequently abnormal but rarely measured and infrequently plotted on centile charts. Neurologists should be alert to potential systemic vascular involvement and its sequelae in children with complex cerebrovascular disease.

This is a case report of a 69-year-old female with treatment-resistant severe arterial hypertension despite prior successful percutaneous intervention to both renal arteries for significant renal artery stenoses (stenting of the right and balloon angioplasty of the left renal artery). The office blood pressure was 221/108 mm Hg at baseline. Secondary hypertension was ruled out and catheter-based renal denervation performed (distal to the stent in the right renal artery and in the usual fashion in the left renal artery) without complications. The office blood pressure decreased at 1- and 3-month follow-up to 185/93 mm Hg and 182/95 mm Hg, respectively. This case illustrates the feasibility and potential efficacy of catheter-based renal denervation in patients with a renal artery stent, an important finding as persistent hypertension is common in patients despite successful renal artery stenting and currently available trials examining renal denervation have excluded patients with prior renal artery stents.

To establish the minimum dose required for detection of renal artery stenosis using high temporal resolution, contrast enhanced MR angiography (MRA) in a porcine model.Surgically created renal artery stenoses were imaged with 3 Tesla MR and digital subtraction angiography (DSA) in 12 swine in this IACUC approved protocol. Gadobutrol was injected intravenously at doses of 0.5, 1, 2, and 4 mL for time-resolved MRA (1.5 × 1.5 mm(2) spatial resolution). Region of interest analysis was performed together with stenosis assessment and qualitative evaluation by two blinded readers.Mean signal to noise ratio (SNR) and contrast to noise ratio (CNR) values were statistically significantly less with the 0.5-mL protocol (P0.001). There were no statistically significant differences among the other evaluated doses. Both readers found 10/12 cases with the 0.5-mL protocol to be of inadequate diagnostic quality (κ = 1.0). All other scans were found to be adequate for diagnosis. Accuracies in distinguishing between mild/insignificant (50%) and higher grade stenoses (50%) were comparable among the higher-dose protocols (sensitivities 73-93%, specificities 62-100%).Renal artery stenosis can be assessed with very low doses (~0.025 mmol/kg bodyweight) of a high concentration, high relaxivity gadolinium chelate formulation in a swine model, results which are promising with respect to limiting exposure to gadolinium based contrast agents.

Long segment narrowing of the thoracoabdominal aorta or so-called middle aortic syndrome (MAS), is an uncommon lesion presenting variably with physical signs of coarctation of the aorta, hypertension, renal insufficiency and or mesenteric ischemia. The etiologies are multiple, but Takayasu's arteritis is a leading cause. Variable involvement of diverse systemic arterial systems requires individualized management strategies. We report a case of a successful treatment algorithm for severe MAS using a strategy of percutaneous aortic endovascular stent implantation to rebuild the distal aorta and renal auto-implantation to address systemic hypertension. © 2011 Wiley Periodicals, Inc.

A type-B acute aortic dissection patient required renal artery revascularization for renal artery stenosis resulting from the compression by a false lumen. Renal artery stenting was complicated by unclear opacification of the ostia resulting from the collapsed true lumen of both renal artery and aorta. The use of the “Szabo” technique facilitated this procedure by allowing us to position the stent edge precisely at the ostium. This is the first report of this technique utilized in this lesion subset. © 2011 Wiley Periodicals, Inc.

Objectives: We evaluated a sheathless transradial technique for interventions using standard five and six French nonhydrophilic guiding catheters. Background: Miniaturization of transradial interventions may serve to improve patient comfort and reduce the risk of access-site complications. Guiding catheters carry an outer diameter approximately 2 Fr sizes smaller than their corresponding introducer sheaths. Methods: We identified consecutive patients who underwent transradial intervention between August 2010 and December 2010 using 5 or 6 Fr guides with a sheathless technique. Results: A total of 11 patients were identified (mean age 70.7 ± 10.9 years; 73% male). Single coronary intervention was performed in 10 patients and renal artery intervention in one. Right radial access and 6 Fr guide catheters were used in the majority (each 73%). Five techniques were used to create an inner dilator as the taper. Four of these inner tapers (standard diagnostic catheters, hydrophilic diagnostic catheters, long sheath dilators and guide extensions) enabled successful sheathless guide insertion in all 10 patients attempted. One technique (a partially inflated angioplasty balloon protruding from the guide) attempted in one patient was unsuccessful. All interventional procedures were successful, there were no radial artery access-site complications and in no case was cross-over to femoral artery access-site required. Conclusion: Sheathless transradial intervention using standard 5 and 6 Fr guiding catheters is a safe and effective method for treatment of coronary and peripheral vascular lesions. © 2011 Wiley Periodicals, Inc.

Purpose. To evaluate the influence of proteinuria on renal Doppler sonographic (US) measurements in patients with chronic kidney disease (CKD) with or without diabetes mellitus (DM). Methods. Renal resistance index (RI), pulsatility index (PI), and maximum kidney length were measured by US in 113 patients suffering from CKD without DM (non-DM CKD patients) and in 120 patients with diabetic nephropathy (DM patients). Other data collected were sex, age, body mass index, blood pressure, estimated glomerular filtration rate, urinary protein level, and medical history. The effect of proteinuria on RI and PI was evaluated using single regression analyses, multiple regression analyses, and comparison of regression lines. Results. Single and multiple regression analyses revealed that RI and PI in the two subgroups and in the entire group of patients were correlated with urinary protein level (p < 0.05). Comparison of regression lines of each subgroup showed statistically significant differences in two regression intercepts concerning these indices in relation to urinary protein level (p < 0.001, RI: 0.71 in non-DM CKD patients versus 0.76 in DM patients, PI: 1.39 in non-DM CKD patients versus 1.60 in DM patients) (p < 0.001). Conclusions. Renal RI and PI can reflect damages related to proteinuria and DM. © 2011 Wiley Periodicals, Inc. J Clin Ultrasound 2011

The Safety and Effectiveness Study of the Herculink Elite Renal Stent to Treat Renal Artery Stenosis (HERCULES) trial is a prospective, multicenter trial evaluating the safety, effectiveness, and durability of the RX Herculink Elite renal stent system (Abbott Vascular, Abbott Park, IL) in select patients with atherosclerotic renal artery stenosis and uncontrolled hypertension. A total of 202 patients were enrolled between August 2007 and October 2009. The primary endpoint, 9‐month binary restenosis, was 10.5% determined by core laboratory adjudicated duplex ultrasound and/or angiography. Additional analyses included changes in blood pressure, antihypertensive medications, renal function (RF), major adverse events (MAEs) (death, ipsilateral nephrectomy, and embolic events resulting in kidney damage), and clinically driven target lesion revascularization (CD‐TLR) between baseline and 36 months. Freedom from MAE was 98.5% at 30 days. At 36 months, freedom from death, nephrectomy, and CD‐TLR were 90.1%, 100%, and 91.8%, respectively. After 30 days there were no site‐reported embolic events resulting in kidney damage. The mean baseline systolic blood pressure of 162±18 mm Hg significantly decreased postprocedure and through 36 months (mean systolic blood pressure 141 mm Hg [P

• Gadolinium-enhanced magnetic resonance angiography (MRA) is highly sensitive in detecting atherosclerotic renal artery stenosis (RAS) and is significantly more accurate in excluding the disease. Gadolinium-based imaging should be avoided in patients with glomerular filtration

OBJECTIVE To compare outcomes between percutaneous transluminal angioplasty and stent placement in the treatment of transplant renal artery stenosis (TRAS). METHODS We retrospectively studied patients who underwent angiography for TRAS between 1/1/2008 and 9/20/2016 at 1 center. We compared the rates of restenosis in patients who were treated with angioplasty alone vs those who were treated with stenting. Secondary outcomes included serum creatinine and blood pressure after intervention and graft and patient survival. RESULTS A total of 82 patients were identified as having TRAS after angiography. Restenosis occurred in 28% (16 of 58) of the angioplasty patients compared with 8% (2 of 24) of the stented patients (P = .04). Repeat angiography occurred in 14% (8 of 58) of angioplasty patients vs 13% (3 of 24) of stented patients (P = .9). The stented group had significantly higher pre-intervention stenosis (71% vs 64%, P = .01) and lower postintervention stenosis (4% vs 30%, P

Purpose: To evaluate the efficacy and safety of 0.1 mmol/kg gadodiamide administration for contrast-enhanced magnetic resonance angiography (MRA) in detecting hemodynamically relevant renal artery stenosis (RAS) when compared with intraarterial digital subtraction angiography (IA-DSA) as the gold standard. Materials and Methods: In a multicenter, controlled study, 395 patients with suspected or known RAS were included. Three independent readers evaluated the MRA images. Two readers evaluated the IA-DSA images and subsequently achieved consensus. The sensitivities and specificities of gadodiamide-enhanced MRA were analyzed at the per-patient and per-vessel levels (exact 1-sided binomial test at α = 0.025 with 95% confidence interval). Results: A total of 335 patients who had available standard of truth and MRA tests were included in the all-subjects efficacy population: 55.5% (186/335) men and 44.5% women with a mean age of 63 ± 13 years (range 17–85 years). The sensitivities and specificities ranged from 81% to 86% for all independent readers at the per-patient analysis based on subjects with the diagnostic images. Similar results were achieved with per-vessel level analysis. Fewer than 1% of patients had adverse event associated with gadodiamide administration. There were no cases of nephrogenic systemic fibrosis (NSF) reported. Conclusion: Gadodiamide administration at the labeled dose of 0.1 mmol/kg for contrast-enhanced MRA achieved equivalent results compared to IA-DSA in evaluation of RAS and was well tolerated. J. Magn. Reson. Imaging 2010; 31: 390–397. © 2010 Wiley-Liss, Inc.

Objective: The objective of this study was to identify the predictors of distal embolization (DE) during protected renal artery angioplasty and stenting. Background: DE may contribute to worsening renal function after renal artery stenting. The factors associated with DE, rates of platelet-rich emboli, and treatments that may prevent DE during renal stenting have not been evaluated. Methods: The current study evaluated patients randomized to receive an embolic protection device (EPD) in the RESIST trial. Forty-two patients were identified for inclusion in this study. These patients were further randomized to abcizimab (N = 22) or placebo (N = 20). Modification in Diet in Renal Disease glomerular filtration rate (GFR) was used as the primary measure of renal function. Creatinine was measured by a modified Jaffe reaction using the IDMS-traceable assay. The primary endpoint was capture of platelet rich emboli in the angioguard basket. Results: DE occurred in 15/42 (35%) of the patients and platelet rich DE in 10 (24%) of the patients who received an EPD. Of the angiographic characteristics only lesion length was significantly higher in patients with DE (16 ± 7 mm vs. 10 ± 5 mm, P = 0.04). Preprocedural abciximab reduced DE from 42 to 8% (P = 0.02). The rate of platelet rich emboli was 50% with neither abciximab nor a thienopyridine, 36% with thienopyridine only, 15% abciximab only, and 0% in patients who received both a thienopyridine and abciximab. Only Abciximab use was associated with improved renal function at 1-month, thienopyridine was not. Angiographic characteristics including percent stenosis, minimal luminal diameter (MLD), reference diameter, change in MLD, contrast volume, and procedure time were not predictors of DE during renal stenting. Conclusion: Capture of DE and specifically platelet DE are common during protected renal stenting using a filter-type EPD. Abciximab use, and potentially combined thienopyridine and abciximab use, decreased the rate of platelet rich DE; however, only abciximab improved renal function at 1-month. © 2010 Wiley-Liss, Inc.

Purpose: To assess the effect of attaining higher spatial resolution in contrast-enhanced magnetic resonance angiography (MRA) of renal arteries using parallel imaging, sensitivity encoding (SENSE), by comparing the SENSE contrast-enhanced (CE) MRA against a conventional CE-MRA protocol with identical scan times, injection protocol, and other acquisition parameters. Materials and Methods: Numerical simulations and a direct comparison of SENSE-accelerated versus conventional acquisitions were performed. A total of 41 patients (18 male) were imaged using both protocols for a direct comparison. Both protocols used fluoroscopic triggering, centric encoding, breath-holding, equivalent injection protocol, and lasted ≈30 seconds. Results: Simulated point-spread functions were narrower for the SENSE protocol compared to the conventional protocol. In the patient study, although the SENSE protocol produced images with lower signal-to-noise ratio (SNR), image quality was better for all segments of the renal arteries. In addition, ringing of kidney parenchyma and renal artery blurring were significantly reduced in the SENSE protocol. Finally, reader confidence improved with the SENSE protocol. Conclusion: Despite a reduction in SNR, the higher-resolution SENSE CE-MRA provided improved image quality, reduced artifacts, and increased reader confidence compared to the conventional protocol. J. Magn. Reson. Imaging 2010;31:149–159. © 2009 Wiley-Liss, Inc.

The detection of the association between nephrogenic systemic fibrosis (NSF), a rare but potentially life-threatening disease only encountered in patients with severely impaired renal function, and the previous administration of some Gd-chelates has cast a shadow on the administration of Gd-chelates in patients with chronic renal failure. So far, contrast-enhanced MR-angiography (MRA) was considered the best diagnostic modality in patients with suspected renal disease. This review explores the most appropriate use of renal MRA with a focus on newly developed nonenhanced MRA techniques. Nonenhanced MRA techniques mainly based on SSFP with ECG-gating allow for acceptable spatial resolution to visualize at least the proximal parts of the renal arteries. In addition functional renal imaging techniques and their current clinical role are critically appreciated. J. Magn. Reson. Imaging 2009;30:1323-1334. (c) 2009 Wiley-Liss, Inc.

Transradial vascular access for invasive procedures is gaining increasingly acceptance due to reduced access-site complications and improved patient's comfort compared with transfemoral. However, the adoption of transradial access in peripheral vascular procedures is actually limited by anatomical and technical considerations. Yet, among all the peripheral vascular districts, the renal one seems to be particularly suitable for transradial approach. In this article, we discuss the rationale for preferring the radial approach instead of femoral and review the specific technical issues related to transradial renal artery stenting (RAS). © 2009 Wiley-Liss, Inc.

Background Patients with symptomatic peripheral artery disease (PAD) are considered cardiovascular high-risk patients. Our aim was to investigate whether incidental renal artery stenosis (RAS) increases the risk for adverse cardiovascular and renal outcomes in these patients. Materials and methods We prospectively enrolled 487 consecutive patients admitted for revascularization of symptomatic PAD and performed a renal overview angiogram categorizing RAS as absent (0–29%), moderate (30–59%) and severe (≥ 60%) respectively. Clinical follow-up was for median 15 months (IQR 12–22) for the occurrence of major adverse events [MAE: composite of death, myocardial infarction (MI), stroke, percutaneous coronary intervention, coronary bypass surgery, amputation and kidney failure]. Glomerular filtration rates (GFR) were obtained at 12 months to quantify the course of renal function. Results A severe RAS was found in 76 patients (15·6%). Overall MAE occurred in 121 patients (24·8%), the composite endpoint of MI, stroke, amputation and death occurred in 101 patients (20·7%). Patients with a severe RAS had a 1·87-fold increased adjusted risk for MAE (95% CI 1·12–3·12, P = 0·017), a 2·51-fold increased adjusted risk for occurrence of the composite endpoint of MI, stroke, amputation and death (95% CI 1·45–4·34, P = 0·001) and a 2·93-fold increased risk for death (95% CI 1·41–6·08, P = 0·004), compared to those of patients without RAS respectively. We observed a significant association between the decrease of GFR over the 12-month follow-up period and the severity of RAS by multivariable analysis (P = 0·044). Conclusion Severe RAS in patients with symptomatic PAD is an independent predictor of major adverse cardiovascular events, adverse renal outcome and mortality.

Left renal artery stenosis was produced in a group of rats. In a second group left renal denervation was performed simultaneously with and in a third group 3 weeks before the stenosing operation. In a fourth group of rats only left renal denervation was performed. The rats were studied with respect to blood pressure and histochemically demonstrable adrenergic nerve patterns in the left kidney. In rats with left renal artery stenosis and hypertension the adrenergic nerve pattern in the left kidney was abolished during the early phase of the blood pressure elevation. The nerves were rendered visible after incubation of kidney specimens in α-methyl-norepinephrine. A significant number of rats with left renal artery stenosis and histochemically proven complete left renal denervation developed hypertension. It is concluded that the adrenergic innervation of the juxta-glomerular cells plays a moderatory but dispensable role in the sequence of events leading to an increased renin release with concequent hypertension in renal artery stenosis.

In a series comprising 482 patients with hypertension requiring treatment 79 percent had to be classified as essential hypertension. Bilateral renal disease was found in 9 percent, unilateral renal disease in 3.3 percent, but only one patient underwent surgery. Renal artery stenosis was found in 24 patients (5 percent), but only 5 (1 percent) were operated on. Two cases of primary hyperaldosteronism and one of phaeochromocytoma were found; in all three surgical intervention was successful. Oral contraceptives had caused the elevated BP in 7 patients (1.5 percent). It is emphasized that the frequency of curable hypertension is still very low and this should be taken into account when routine examination of patients with hypertension requiring treatment is discussed.

In 79 patients (50 with parenchymatous renal disease, 19 with unilateral stenosis of the main stem of the renal artery, and ten with renal carcinoma) the diameters of the renal arteries (Dra) were measured by renal arteriography, and the effective renal blood flow (ERBF), the inulin clearance (Cin), and the para-amino-hippuric acid clearance (CPAH) were measured by the split function technique. In the patients with single renal arteries and parenchymatous renal disease positive, curvilinear covariations between ERBF, Cin, CPAH and Dra as well as D2ra were found. When the difference in function between the kidneys in the same individual (per cent of mean value) was correlated with the corresponding difference in Dra, significant, positive, linear covariations between ERBF, Cin, CPAH and Dra as well as D2ra, were found in patients with single renal arteries and parenchymatous renal disease. There was no correlation between the functional parameters and Dra in the kidneys with renal artery stenosis or renal carcinoma. It seems that Dra is so closely related to the blood flow through the renal artery, when the variation of Dra is secondary to modifications in the parenchyma, that it can be used as approximate estimate of renal function.

The response of peripheral venous plasma angiotensin II (A-II) to upright posture combined with an injection of furosemide was higher in patients with hypertension and associated renal parenchymal disease, renal artery stenosis or malignant hypertension than in patients with essential hypertension and normotensive control patients. Very low responses to the same stimuli were observed in primary aldosteronism. Markedly increased A-II levels were measured in the renal veins of the affected kidneys in hypertensive patients with associated unilateral renal parenchymal disease or renal artery stenosis, suggesting that human kidneys contain considerable converting enzyme activity. Plasma A-II levels were normalized in three patients with primary aldosteronism after removal of an adrenal adenoma and in one patient with malignant hypertension after bilateral nephrectomy and renal transplantation.

A study is presented of 329 records of patients on whom angiography had been performed. Fifteen complications were found (4.6%). These are listed in Table IV The five complications occurring in connection with nephroangiographies performed in the investigation of hypertension are assessed against the benefit obtained. Only three patients out of 101 investigated have derived any benefit from the resulting operation. Some of the literature is reviewed and the authors conclude that the indications for nephroangiography in the investigation of hypertension might be modified by the inclusion of other selective investigations.