Renal Vascularization Research Articles

Accessory Renal Arteries: A Cadaveric Study

Objectives : The precise knowledge of renal vascular pattern is significant in conduct of various renal surgeries, interventional radiology, and urologic procedures. Variations in renal vascularization have assumed greater importance in conservative surgeries; hence the presence of accessory arteries cannot be overlooked during segmental resection, partial nephrectomy and renal transplants. The aim of the study was to establish the incidence and characteristics of accessory arteries in human kidneys. Methods: The study was carried out on fifty adult cadaver kidneys. They were stored in 10% formalin and treated with 5% KOH solution for 72 hours prior to dissection. Dissection of the kidneys was done keeping in mind the orientation of poles, borders and surfaces. The branching pattern of renal artery was studied. Accessory arteries were observed in terms of their origin, number, side,location and formation of independent segments. Results: Accessory arteries were seen in eleven kidneys (22%). All were arising from the abdominal aorta. These were more common on the left side and at the lower pole. Two accessory arteries were seen in one kidney (9.4%). Accessory arteries were seen more on anterior surface and formed independent arterial segments in seven kidneys (63.7%). Conclusion: The recognition of accessory arteries is anatomically significant and of paramount importance in surgical and radiological practice.

Evaluation of the relationship between renal function and renal volume-vascular indices using 3D power Doppler ultrasound

PurposeTo investigate the relationship between renal function and total renal volume-vascular indices using 3D power Doppler ultrasound (3DPDUS). Materials and methodsOne hundred six patients with hypertensive proteinuric nephropathy (HPN) (49 male, 57 female) and 65 healthy controls (32 male, 33 female) were evaluated prospectively using 3DPDUS. Total renal volume (RV), vascularization index (VI), flow index (FI) and vascularization flow index (VFI) were calculated using Virtual Organ Computer-aided Analysis (VOCAL). The estimated glomerular filtration rates (GFRs) of the patients with HPN and the control group were calculated. The patients with HPN were divided into two groups on the basis of GFR, normal (≥90) or reduced (<90). Differences between groups were compared using ANOVA. Correlations between GFR, renal volume and vascular indices were analyzed using Pearson's correlation analysis. Significance was set at p<0.05. ResultsThe mean total RV, VI, FI and VFI values in the reduced GFR, normal GFR and control groups were RV (ml): 234.7, 280.7 and 294.6; VI: 17.6, 27.6 and 46.8; FI: 79.1, 88.7 and 93.9 and VFI: 7.1, 12.7 and 23.8. There were statistically significant differences between the groups (p<0.001). Total RVs and vascular indices exhibited significant correlations with estimated GFR (r=0.53–0.59, p<0.001) ConclusionThree-dimensional power Doppler ultrasound is a reliable predictive technique in renal function analysis.

Near Infrared Fluorescence Imaging to Aid in Selective Arterial Clamping

Abstract Introduction: Near infrared fluorescence imaging with indocyanine green (ICG) is an adjunct technology to facilitate intraoperative assessment of renal vascularization and tissue perfusion...

Diagnostic value of vascular endothelial growth factor determination in chronic pyelonephritis in children

Aim. This paper is devoted to the evaluation of clinical and diagnostic value of vascular endothelial growth factor detection in chronic pyelonephritis in children. Methods. The study included 62 patients with different compensation degrees of the disease. Patients were divided into 2 groups - subcompensation (37 patients), and decompensation (25 patients). Renal function was assessed by glomerular filtration rate. Vascular endothelial growth factor concentration was determined by the enzyme-linked immunosorbent assay. To assess the renal vasculature, triplex ultrasonography using pulsed Doppler was performed. The endothelial dysfunction was examined by postocclusion test with reactive hyperemia. Results. Vascular endothelial growth factor level had been significantly increasing in patients according to the severity of the disease. The vascular endothelial growth factor concentration exceeded 600 pg/ml all patients who has later developed chronic renal failure. The sensitivity of this indicator at the abovementioned critical point was assessed as 80%. The change of resistance index reflected renal vascularization disorders. The endothelial dysfunction in postocclusion test was also revealed in patients with pyelonephritis. The vascular endothelial growth factor level highly correlated with the glomerular filtration rate and resistance index. Conclusion. Detecting the vascular endothelial growth factor serum level is one of the tools for endothelial dysfunction laboratory monitoring and renal function assessment in in children with chronic pyelonephritis.

In Vivo Cardiovascular Pharmacology of 2′,3′-cAMP, 2′-AMP, and 3′-AMP in the Rat

The naturally occurring purine 2',3'-cAMP is metabolized in vitro to 2'-AMP and 3'-AMP, which are subsequently metabolized to adenosine. Whether in vivo 2',3'-cAMP, 2'-AMP, or 3'-AMP are rapidly converted to adenosine and exert rapid effects via adenosine receptors is unknown. To address this question, we compared the cardiovascular and renal effects of 2',3'-cAMP, 2'-AMP, 3'-AMP, 3',5'-cAMP, 5'-AMP, and adenosine in vivo in the rat. Purines were infused intravenously while monitoring mean arterial blood pressure (MABP), heart rate (HR), cardiac output, and renal and mesenteric blood flows. Total peripheral (TPR), renal vascular (RVR), and mesenteric vascular (MVR) resistances were calculated. Urine was collected for determination of urine excretion rate [urine volume (UV)]. When sufficient urine was available, the sodium excretion rate (Na(+)ER) and glomerular filtration rate (GFR) were determined. 2',3'-cAMP, 2'-AMP, and 3'-AMP dose-dependently and profoundly reduced MABP, HR, TPR, and MVR with efficacy and potency similar to adenosine and 5'-AMP. These effects of 2',3'-cAMP, 2'-AMP, and 3'-AMP were attenuated by blockade of adenosine receptors with 1,3-dipropyl-8-(p-sulfophenyl)xanthine. 2',3'-cAMP, 2'-AMP, 3'-AMP, adenosine, and 5'-AMP variably affected RVR, but profoundly (nearly 100%) decreased UV at higher doses. GFR and Na(+)ER could be measured at the lower doses and were suppressed by 2',3'-cAMP, 2'-AMP, and 3'-AMP, but not by adenosine or 5'-AMP. 2',3'-cAMP increased urinary excretion rates of 2'-AMP, 3'-AMP, and adenosine. 3',5'-cAMP exerted no adverse hemodynamic effects yet increased urinary adenosine as efficiently as 2',3'-cAMP. In vivo 2',3'-cAMP is rapidly converted to adenosine. Because both cAMPs increase adenosine in the urinary compartment, these agents may provide unique therapeutic opportunities.

Is the renin–angiotensin system actually hypertensive?

The historical view of the renin-angiotensin system (RAS) is that of an endocrine hypertensive system that is controlled by renin and mediated via the action of angiotensin II on its type 1 receptor. Numerous new angiotensins (Ang) and receptors have been described, the majority being hypotensive and natriuretic, namely Ang-(1-7) and its receptor rMas. Renin and its precursor (pro-renin) can bind their common receptor. In addition to the production of Ang II, this receptor triggers intracellular effects. Given the control of renin production by intracellular calcium, calcium homeostasis is of particular importance. Ang-(1-12), which is not controlled by renin, is converted to several different angiotensin peptides and is a new pathway of the RAS. Local RAS enzymes produce or transform the different hyper- or hypotensive angiotensin within vessels and organs, but also in blood through circulating forms of the enzymes. In the kidney, a powerful local vascular RAS allows for the independence of renal vascularization from systemic control. Moreover, the kidney also contains an independent urinary RAS, which counterbalances the systemic RAS and coordinates proximal and distal sodium reabsorption. The systemic and local effects of renal RAS cannot be analyzed without taking into account the antagonistic effect of renalase. Our concept of RAS needs to evolve to take into account its dual potentiality (hyper- or hypotensive).

Two- and Three-Dimensional Contrast-Enhanced Sonography for Assessment of Renal Tumor Vasculature

The purpose of this study was to show potential applications of 2-dimensional (2D) and 3-dimensional (3D) contrast-enhanced sonography for assessment of the vascularity of benign and malignant renal tumors. Sixty-eight patients with renal tumors were examined with both 2D and reconstructed 3D contrast-enhanced sonography. The contrast enhancement characteristics of benign and malignant renal tumors were compared on both 2D and 3D contrast-enhanced sonograms. The diagnoses of the lesions were made by surgical pathologic examination in 50 patients and by contrast-enhanced computed tomography in 18 patients. Both 2D and 3D contrast-enhanced sonography showed hypoenhancement with a few small peritumoral feeding blood vessels and regular intratumoral branches in 18 benign tumors, whereas hyperenhancement with multiple irregular peritumoral feeding vessels and tortuous intratumoral branches was shown in 50 malignant tumors. Compared to 2D contrast-enhanced sonography, 3D contrast-enhanced sonography displayed more intratumoral microvessels and spatial distributions, especially for the vessel network, and tortuous branches in the malignant tumors. Compared to 2D contrast-enhanced sonography, 3D contrast-enhanced sonography was better for detecting and displaying renal tumor vascularity, with a statistically significant difference (P < .05). Reconstructed 3D contrast-enhanced sonography is a useful complementary tool in addition to 2D contrast-enhanced sonography for assessing the characteristics and distribution of blood vascularity in renal tumors.

P27.05: Quantification of renal vascularity by 3D‐power Doppler ultrasonography in normal fetuses

using the VOCAL (Virtual Organ Computer-aided AnaLysis) imaging program which is integrated into the Voluson E8 ultrasound system. The intrauterine content was sent for microscopic examination. The findings were compared with corresponding volumes and findings from women with uncomplicated postpartum periods from a previous study. Results: In 17 of the 20 cases placental remnants were verified by the microscopic examination. Five of these women had a uterine volume that exceeded the largest interquartile volume observed in women with a normal puerperium and in 4 the volume exceeded the largest volume observed in the normal puerperium. The other 12 women had normal uterine volumes. Fifteen of the 17 women with placental remnants had a uterine cavity volume that exceeded the interquartile volume observed in women with a normal puerperium and in 13 the volume exceeded the largest volume observed in the normal puerperium. In all 9 cases examined 42 days or more after delivery the uterine cavity volume exceeded the largest volume observed in the normal puerperium. In all examined women an echogenic mass was seen in the uterine cavity. Conclusions: The uterine and especially the uterine cavity volumes are often larger in women with placental remnants compared to women with an uneventful postpartum course. This knowledge can be of help when placental remnants are to be verified or ruled out. A finding of an echogenic mass in the cavity has a strong correlation with the presence of placental remnants.

Diagnosis of Acute Cortical Necrosis in Renal Transplantation by Contrast-Enhanced Ultrasound: a Preliminary Experience

To evaluate the use of contrast-enhanced ultrasound (CEUS) for diagnosis of cortical necrosis in renal allografts. We reviewed the medical records and imaging studies of five patients who underwent emergency transplantectomy and a histological diagnosis of cortical necrosis in the period between May 2009 and May 2011. US examinations included initially B-mode and color Doppler and then contrast-enhanced ultrasound with low mechanical index after injection of 2.4 ml of a second generation echo-signal enhancer. Renal transplant vascularization was evaluated during a period of 4 minutes including arterial, corticomedullary and nephrographic phases. Radiologic-pathologic correlation was obtained after transplantectomy in all cases. Five patients with an age range between 30 and 48 years. Post-transplant color Doppler ultrasound showed decreased renal parenchymal vascularization and difficulty to find the spectral waveforms with resistive indexes greater than 0.7 in 4 of 5 patients. CEUS showed enhancement of the main arteries, followed by the enhancement of medullary pyramids, but with an unenhanced peripheral cortical continuous band viewed in all phases, a similar finding to the peripheral rim sign, pathognomonic of cortical necrosis on CT or MRI. The pathologic assessment showed violet kidneys macroscopically with hemorrhagic foci in the outer cortical that drew a well-defined band, findings agreed with CEUS findings. CEUS can show the typical peripheral rim sign in cases of cortical necrosis allowing a reliable and fast diagnosis of this condition and it could obviate further imaging studies or biopsy, allowing an earlier decision of nephrectomy.

Particularities of blood vessels correlate with VEGF expression in human renal medulla

In the normal kidney, VEGF is constitutively expressed in podocytes and tubular epithelial cells of the renal cortex and medulla. This study determined the particularities of renal vascularization and VEGF expression in renal medulla using immunohistochemical methods on normal kidneys samples taken from 28 patients. Sections were stained with routine haematoxylin‐eosin method and immunohistochemically for VEGF, CD34, CD31 and SMA. All cases presented an intense immunoreaction for VEGF in the cells lining the nephron tubular system, the higher immunoreaction intensity in the collecting and distal tubules, but weak or moderate in the proximal tubules. The Henle loop cells showed a negative immunoreaction. The VEGF immunostaining was significantly higher in outer than inner medulla. In outer portion of outer medulla we identified using vascular markers, two types of vascular plexus: peritubular plexus around contort and collector tubules of outer zone of outer medulla and segmentary capillary plexal nodes near vasa recta. The strong positive immunoreaction for VEGF in the collecting ducts and distal tubules epithelial cells suggest a relationship between VEGF expression and adjacent straight vessels (vasa recta), with important roles in gradient concentration, being known that VEGF was initially named vascular permeability factor.

Technical Note and Results in the Management of Anatomical Variants of Renal Vascularisation during Endovascular Aneurysm Repair

IntroductionThe revascularisation of large (>3 mm) renal arteries emerging from the proximal sealing zone or off the aneurismal wall can be challenging during endovascular aortic aneurysm repair. In this article, we describe various endovascular techniques using custom-made endografts to treat these complex variant anatomies. CasesNine patients deemed unfit for open repair with unusual renal vascularisation associated with aortic aneurysms were treated by endovascular means. After three-dimensional (3D) reconstructions on a dedicated workstation, custom-made devices were designed and manufactured. The revascularisation of multiple renal arteries and aberrant origins of renal arteries, associated or not with pelvic kidney or horseshoe kidney, was managed using fenestrated and branched endografts. ResultsAll target vessels were patent on computed tomography (CT) scan and contrast-enhanced ultrasound evaluation before discharge as well as on the 6-month follow-up. One patient presented a decrease of postoperative glomerular filtration rate over 30% but did not require dialysis. No sac enlargement was depicted, and no reintervention was performed during follow-up. Three type 2 endoleaks were diagnosed. ConclusionEndovascular treatment with fenestrated and branched endografts should be considered in challenging renal artery anatomies in patients unfit for open repair.

Deficiency in Plasminogen Cause Decreased Vascularity in Sold Tissue Organs and Bone

Abstract 857A sufficient vascular supply is critical for proper physiologic function of solid-tissue organs and bone. Tissue vascularity is mediated concomitantly through vascular patency and angiogenesis. Recently, numerous studies have associated plasminogen, the key fibrinolytic protease of the coagulation system, with maintaining vascular patency by preventing fibrin accumulation with in the vasculature. Additionally, plasminogen may also have a direct role in angiogenesis as it has been shown in vitro that inhibitors of plasmin(ogen) suppress formation of capillary structures from normal endothelial cells and cells cultured from plasmin(ogen) deficient mice have reduced capillary sprouting in response to the angiogenic stimulator VEGF-A. Therefore, we hypothesized that plasminogen is essential for developing and maintaining vascularity in solid-tissue organs and revascularization of bone fracture calluses. To determine if there was a discernable difference in vivo between the vascular supply of plasminogen deficient (plg−/−) and wild type mice we performed microfil profusion studies visualized using a Sanco 40 μCT. We determined that plg−/− mice have a diminished renal and hepatic vascularity compared to wild type mice at 3 and 20 weeks of age (Figure 1). Further, we show that plg−/− mice fail to develop a blood supply at the fracture site by week 2 post-fracture whereas the control mice exhibit a highly neovascularized capillary system (Figure 2). Plg −/− mice also fail to develop a mineralized callus around a two week old fracture site demonstrating a role for plasmin(ogen) in osteoblast minimization. These findings demonstrate that disruption of the fibrinolytic system’s main proteolytic enzyme plasmin results in decreased vascularity of solid-tissue organs and revascularization of bone fracture calluses. While the role of plasmin(ogen) in vascularity is clear, further studies are warranted to elucidate its mechanisms of action. Studies investigating plasmin(ogen)’s role in vascularity may have importance in variety of biologic conditions and pathologies. For example, aging, diabetes and smoking, all of which are known to incur an acquired deficiency or dysfunction of fibrinolysis lead to complications of vascularity (cardiovascular disease) and are also associated with pathologic bone disease (osteoporosis and poor fracture healing). These data indicate that plasmin(ogen) and its biologic targets may provide future novel therapeutic targets for treatment of pathologies involving impaired vascularization. [Display omitted] [Display omitted] Disclosures:No relevant conflicts of interest to declare.

The Western-style diet: a major risk factor for impaired kidney function and chronic kidney disease

The Western-style diet is characterized by its highly processed and refined foods and high contents of sugars, salt, and fat and protein from red meat. It has been recognized as the major contributor to metabolic disturbances and the development of obesity-related diseases including type 2 diabetes, hypertension, and cardiovascular disease. Also, the Western-style diet has been associated with an increased incidence of chronic kidney disease (CKD). A combination of dietary factors contributes to the impairment of renal vascularization, steatosis and inflammation, hypertension, and impaired renal hormonal regulation. This review addresses recent progress in the understanding of the association of the Western-style diet with the induction of dyslipidemia, oxidative stress, inflammation, and disturbances of corticosteroid regulation in the development of CKD. Future research needs to distinguish between acute and chronic effects of diets with high contents of sugars, salt, and fat and protein from red meat, and to uncover the contribution of each component. Improved therapeutic interventions should consider potentially altered drug metabolism and pharmacokinetics and be combined with lifestyle changes. A clinical assessment of the long-term risks of whole-body disturbances is strongly recommended to reduce metabolic complications and cardiovascular risk in kidney donors and patients with CKD.

Quantitative analysis of renal vascularization in fetuses with urinary tract obstruction by three-dimensional power-Doppler

To evaluate the applicability of 3-dimensional evaluation of renal vascularization for predicting postnatal renal function in fetuses with suspected urinary obstruction. Fetuses were evaluated by 3-dimensional power-Doppler histogram, and vascular indices were estimated. Depth between the probe and the renal cortex was also evaluated. Postnatal follow-up was obtained in all cases and the main outcome was renal impairment. Twenty-three fetuses with urinary dilatation (cases) and 73 with normal renal morphology (controls) were included in the current study. Five (21.7%) cases developed renal impairment. Vascularization index and vascularization and flow index were significantly lower in fetuses that developed renal impairment compared with those with normal renal function (P = .009 and P = .036, respectively). The 3 vascular indexes correlated with depth. Percentage of depth-corrected vascularization index and vascularization flow index were lower in fetuses developing postnatal renal failure. Fetal renal vascularity (vascularization index and vascularization and flow index) was significantly lower in fetuses that developed renal impairment.

Anatomical variations of polar renal arterial sources and their clinical importance

Normally, the polar parenchymas are distinctive segments supplied by the segmental branches of the renal artery. The study, which was conducted using 20 CT angiographies and 40 kidney dissections and microdissections, revealed 14 cases of polar arteries (6 superior and 8 inferior). Their origin and importance in the vascularisation of the renal poles were analysed. The superior polar arteries originated in the abdominal part of the aorta (supernumerary arteries) in 2 cases and in the renal artery in 4 cases (polar renal arteries). One of the left superior polar renal arteries had a venous branch and a nerve plexus that together formed a vasculo‐nervous pedicle. In 2 of the 5 superior artery cases, the superior polar arteries were the single arterial source of the superior pole. In the other 3 cases, the polar arteries joined several segmental branches originating in the anterior branch of the renal artery trunk (2 cases) and in the posterior branch (1 case). The inferior polar arteries originated from the aorta in 7 cases and from the left gonadal artery (travelling anterior to the ureter) in one case. In all cases of inferior polar arteries, these were associated with inferior segmental arterial branches. Familiarity with renal artery vascularisation and its numerous variants is an important aspect involved in the preoperative evaluation of patients undergoing urological interventions.

Évaluation préopératoire du nombre de vaisseaux chez le donneur de rein vivant. La TDM est-elle supérieure à l’IRM ?

computed tomography angiography (CTA) and magnetic resonance angiography (MRA) are both used in the preoperative assessment of vascular anatomy before donor nephrectomy. Our objective was to determine retrospectively and to compare the sensitivity of CTA and MRA imaging in preoperative renal vascularisation in living kidney donors. between 1999 and 2007, 42 kidney donors were assessed in our center: 27 by MRA, 10 by CTA, and five by both techniques. Images were interpreted using multiplanar reconstructions. Results were compared retrospectively with peroperative findings; discordant cases were re-examined by an experienced radiologist. Numbers of vessels detected with imaging methods was compared with numbers actually found at the operating time. MRA showed 35/43 arteries (Se 81.4 %) and 33/34 veins (Se 97.1 %), and CTA showed 18/18 arteries (Se 100 %) and 15/16 veins (Se 93.8 %). The presence of multiple arteries was detected in only one third of cases (3/9) on MRI scans; this difference was statistically significant. The missed arteries were not detected on second examination of the MRI scans with the knowledge of peroperative findings. MRA is less sensitive than CTA for preoperative vascularisation imaging in living renal donors, especially in the detection of multiple renal arteries.

Progressive Renal Vascular Proliferation and Injury in Obese Zucker Rats

Obesity, an independent risk factor for chronic kidney disease, may induce renal injury by promoting inflammation. Inflammatory cytokines can induce neovascularization in different organs, including the kidneys. However, whether obesity triggers renal neovascularization and, if so, its effect on renal function has never been investigated. Blood pressure, proteinuria, and glomerular filtration rate (GFR) were measured in vivo. Renal microvascular (MV) architecture was studied by 3D micro-CT in lean and obese Zucker rats (LZR and OZR, n = 7/group) at 12, 22, and 32 weeks of age. Renal inflammation was assessed by quantifying interleukin (IL)-6, tumor necrosis factor (TNF)-alpha, and ED-1 expression, as renal fibrosis in trichrome-stained cross-sections. Mild inflammation and lower GFR was only observed in younger OZR, without renal fibrosis or changes in MV density. Interestingly, renal MV density increased in OZR at 32 weeks of age, accompanied by pronounced increase in renal IL-6 and TNF-alpha, ED-1+ cells, proteinuria, decreased GFR, and fibrosis. This study shows increased renal cortical vascularization in experimental obesity, suggesting neovascularization as an evolving process as obesity progresses. Increased renal vascularization, possibly triggered by inflammation, may reflect an initially compensatory mechanism in obesity. However, increased inflammation and inflammatory-induced neovascularization may further promote renal injury as obesity advances.

Matrix Extracellular Phosphoglycoprotein (MEPE) Is a New Bone Renal Hormone and Vascularization Modulator

Increased matrix extracellular phosphoglycoprotein (MEPE) expression occurs in several phosphate and bone-mineral metabolic disorders. To resolve whether MEPE plays a role, we created a murine model overexpressing MEPE protein (MEPE tgn) in bone. MEPE tgn mice displayed a growth and mineralization defect with altered bone-renal vascularization that persisted to adulthood. The growth mineralization defect was due to a decrease in bone remodeling, and MEPE tgn mice were resistant to diet-induced renal calcification. MEPE protein-derived urinary ASARM peptides and reduced urinary Ca X PO4 product mediated the suppressed renal calcification. Osteoblastic cells displayed reduced activity but normal differentiation. Osteoclastic precursors were unable to differentiate in the presence of osteoblasts. In the kidney, NPT2a up-regulation induced an increase in phosphate renal reabsorption, leading to hyperphosphatemia. We conclude MEPE and MEPE-phosphate-regulating gene with homologies to endopeptidases on the X chromosome (MEPE-PHEX) interactions are components to an age-diet-dependent pathway that regulates bone turnover and mineralization and suppresses renal calcification. This novel pathway also modulates bone-renal vascularization and bone turnover.

Bacterial endocarditis presenting with unilateral renal artery occlusion treated with the Rinspirator Thrombus Removal System rinsing and thrombectomy device and suction thrombectomy

We report a 36-year-old man who presented with unilateral flank pain caused by renal artery occlusion with ischemia and infarction from septic emboli secondary to bacterial endocarditis. We treated the occlusion with a novel rinsing and aspiration device, the Rinspirator Thrombus Removal System (ev3, Plymouth, Minn) and suction thrombectomy, which resulted in significant revascularization of the kidney and relief of symptoms. Postprocedural imaging demonstrated marked improvement in renal vascularization, with only small areas of infarction. This technique may be useful in patients where the embolic material is chronic or thrombolytic agents are contraindicated.

Frequency of renal artery stenosis and variants of renal vascularization in hypertensive patients: analysis of 1550 angiographies in one centre

Renal artery stenosis (RAS) is an important cause of arterial hypertension and chronic kidney disease. The aims of our study were to assess the prevalence of RAS and to examine the frequency of variants of renal vasculature, that is, multiple and/or accessory renal arteries in hypertensive patients referred to renal angiography. We evaluated retrospectively 1554 arteriographies of hypertensive patients. Angiograms were evaluated to find RAS, significant RAS (>60% stenosis of the lumen), radiological signs of atherosclerosis, aneurysms of the renal arteries or aorta and variants of kidney vascularization. The frequency of RAS including occlusions was 15.1% (21.3% of them were significant and suitable for revascularization). Variants of renal arterial vascularization were found in 26.5% of patients (multiple renal arteries-11.2% and accessory renal arteries-15.3%). Significant RAS was found more frequently in patients older than 60 years-OR 4.76 (2.08-10.86). Coronary artery disease, history of myocardial infarction or stroke significantly increased the chance of RAS detection. The frequency of renal accessory arteries was lower in patients older than 60 years and in patients with the radiological signs of atherosclerosis. Results of this study indicate that haemodynamically important RAS is found more frequently in hypertensive patients older than 60 years. Symptomatic atherosclerotic disease found in the peripheral and/or coronary arteries and diabetes mellitus increases the chance of RAS detection. Decreased occurrence of renal accessory arteries was found in hypertensive patients with radiological signs of atherosclerosis.