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Pediatric Nephrology (Berlin, Germany) Jun 2015The renal vasculature, like all vessels, is lined by a thin layer of simple squamous epithelial cells called an endothelium. These endothelial-lined vessels can be... (Review)
Review
The renal vasculature, like all vessels, is lined by a thin layer of simple squamous epithelial cells called an endothelium. These endothelial-lined vessels can be subdivided into four major compartments: arteries, veins, capillaries and lymphatics. The renal vasculature is a highly integrated network that forms through the active processes of angiogenesis and vasculogenesis. Determination of the precise contribution of these two processes and of the molecular signaling that governs the differentiation, specification and maturation of these critical cell populations is the focus of an actively evolving field of research. Although much of the focus has concentrated on the origin of the glomerular capillaries, in this review we extend the investigation to the origins of the endothelial cells throughout the entire kidney and the signaling events that cause their distinct functional and molecular profiles. A thorough understanding of endothelial cell biology may play a critical role in a better understanding of renal vascular diseases.
Topics: Angiogenic Proteins; Animals; Capillaries; Cell Lineage; Endothelial Cells; Endothelium, Lymphatic; Endothelium, Vascular; Gene Expression Regulation, Developmental; Humans; Kidney; Kidney Diseases; Neovascularization, Physiologic; Organogenesis; Renal Artery; Renal Veins; Signal Transduction
PubMed: 24633402
DOI: 10.1007/s00467-014-2798-3 -
PloS One 2015Recently, the efficacy of renal denervation (RDN) has been debated. It is discussed whether RDN is able to adequately target the renal nerves.
RATIONALE
Recently, the efficacy of renal denervation (RDN) has been debated. It is discussed whether RDN is able to adequately target the renal nerves.
OBJECTIVE
We aimed to investigate how effective RDN was by means of functional hemodynamic measurements and nerve damage on histology.
METHODS AND RESULTS
We performed hemodynamic measurements in both renal arteries of healthy pigs using a Doppler flow and pressure wire. Subsequently unilateral denervation was performed, followed by repeated bilateral hemodynamic measurements. Pigs were terminated directly after RDN or were followed for 3 weeks or 3 months after the procedure. After termination, both treated and control arteries were prepared for histology to evaluate vascular damage and nerve damage. Directly after RDN, resting renal blood flow tended to increase by 29±67% (P = 0.01). In contrast, renal resistance reserve increased from 1.74 (1.28) to 1.88 (1.17) (P = 0.02) during follow-up. Vascular histopathology showed that most nerves around the treated arteries were located outside the lesion areas (8±7 out of 55±25 (14%) nerves per pig were observed within a lesion area). Subsequently, a correlation was noted between a more impaired adventitia and a reduction in renal resistance reserve (β: -0.33; P = 0.05) at three weeks of follow-up.
CONCLUSION
Only a small minority of renal nerves was targeted after RDN. Furthermore, more severe adventitial damage was related to a reduction in renal resistance in the treated arteries at follow-up. These hemodynamic and histological observations may indicate that RDN did not sufficiently target the renal nerves. Potentially, this may explain the significant spread in the response after RDN.
Topics: Animals; Denervation; Hemodynamics; Humans; Hypertension; Kidney; Pressure; Renal Artery; Renal Circulation; Swine; Sympathetic Nervous System
PubMed: 26587981
DOI: 10.1371/journal.pone.0141609 -
BMC Cancer Mar 2023To explore the characteristics of renal artery variation in patients with renal cell carcinoma and to evaluate the predicting value of accessory renal artery in the... (Observational Study)
Observational Study
Characterization of renal artery variation in patients with clear cell renal cell carcinoma and the predictive value of accessory renal artery in pathological grading of renal cell carcinoma: a retrospective and observational study.
OBJECTIVE
To explore the characteristics of renal artery variation in patients with renal cell carcinoma and to evaluate the predicting value of accessory renal artery in the pathological grading of renal cell carcinoma.
METHODS
The clinicopathological data of patients with clear cell renal cell carcinoma diagnosed in the Department of Urology of the First Hospital of Shanxi Medical University from September 2019 to March 2023 were retrospectively analyzed. All patients underwent visual three-dimensional model reconstruction from computed tomography images. All kidneys were divided into two groups: the affected kidney and the healthy kidney, and the incidence of renal artery variation in the two groups was analyzed. Then, according to the existence of accessory renal artery in the affected kidney, the patients were divided into two groups, and the relationship between accessory renal artery and clinicopathological features of patients with clear cell renal cell carcinoma was analyzed. Finally, univariate and multivariate logistic regression analyses were performed to determine the predictors of Fuhrman grading of clear cell renal cell carcinoma, and the predictive ability of the model was evaluated by the receiver operating characteristic curve.
RESULTS
The incidence of renal artery variation and accessory renal artery in the affected kidney was significantly higher than them in the healthy kidney. The patients with accessory renal artery in the affected kidney had larger tumor maximum diameter, higher Fuhrman grade and more exophytic growth. The presence of accessory renal artery on the affected kidney and the maximum diameter of tumor are independent predictors of high-grade renal cell carcinoma. The receiver operating characteristic curve suggests that the model has a good predictive ability.
CONCLUSION
The existence of accessory renal artery on the affected kidney may be related to the occurrence and development of clear cell renal cell carcinoma, and can better predict Fuhrman grade of clear cell renal cell carcinoma. The finding provides a reference for the future diagnostic evaluation of RCC, and provides a new direction for the study of the pathogenesis of RCC.
Topics: Humans; Carcinoma, Renal Cell; Kidney Neoplasms; Retrospective Studies; Renal Artery; Neoplasm Grading
PubMed: 36966274
DOI: 10.1186/s12885-023-10756-y -
Canadian Medical Association Journal Apr 1968
Review
Topics: Adult; Aneurysm; Humans; Hypothermia, Induced; Male; Renal Artery; Transplantation, Autologous; Urography; Veins
PubMed: 4869680
DOI: No ID Found -
Journal of Vascular Surgery Apr 2016The durability of stent grafts may be related to how procedures and devices alter native anatomy. We aimed to quantify and compare renal artery geometry before and after... (Comparative Study)
Comparative Study
OBJECTIVE
The durability of stent grafts may be related to how procedures and devices alter native anatomy. We aimed to quantify and compare renal artery geometry before and after fenestrated (F-) or snorkel/chimney (Sn-) endovascular aneurysm repair (EVAR).
METHODS
Forty patients (75 ± 6 years) underwent computed tomographic angiography before and after F-EVAR (n = 21) or Sn-EVAR (n = 19), with a total of 72 renal artery stents. Renal artery geometry was quantified using three-dimensional model-based centerline extraction. The stented length was computed from the vessel origin to the stent end. The branch angle was computed relative to the orthogonal configuration with respect to the aorta. The end-stent angle was computed relative to the distal native renal artery. Peak curvature was defined as the inverse of the radius of the circumscribed circle at the highest curvature within the proximal portion from the origin to the stent end and the distal portion from the stent end to the first renal artery bifurcation.
RESULTS
Sn-renals had greater stented length compared to F-renals (P < .05). From the pre- to the postoperative period, the origins of the Sn-left renal artery and right renal artery (RRA) angled increasingly downward by 21 ± 19° and 13 ± 17°, respectively (P < .005). The F-left renal artery and RRA angled upward by 25 ± 15° and 14 ± 15°, respectively (P < .005). From the pre- to the postoperative period, the end-stent angle of the Sn-RRA increased by 17 ± 12° (P < .00001), with greater magnitude change compared to the F-RRA (P < .0005). Peak curvature increased in distal Sn-RRAs by .02 ± .03 mm(-1) (P < .05). Acute renal failure occurred in 12.5% of patients, although none required dialysis following either F- and Sn-EVAR. Renal stent patency was 97.2% at mean follow-up of 13.7 months. Three type IA endoleaks were identified, prompting one secondary procedure, with the remainder resolving at 6-month follow-up. One renal artery reintervention was performed due to a compressed left renal stent in an asymptomatic patient.
CONCLUSIONS
Stented renal arteries were angled more inferiorly after Sn-EVAR and more superiorly after F-EVAR due to stent configuration. Sn-EVAR induced significantly greater angle change at the stent end and curvature change distal to the stent compared to F-EVAR, although no difference in patency was noted in this small series with relatively short follow-up. Sn-RRAs exhibited greater end-stent angle change from the pre- to the postoperative period as compared to the F-RRA. These differences may exert differential effects on long-term renal artery patency, integrity, and renal function following complex EVAR for juxta- or pararenal abdominal aortic aneurysms.
Topics: Aged; Aged, 80 and over; Aortic Aneurysm, Abdominal; Aortography; Blood Vessel Prosthesis; Blood Vessel Prosthesis Implantation; Endovascular Procedures; Female; Humans; Imaging, Three-Dimensional; Male; Predictive Value of Tests; Prospective Studies; Prosthesis Design; Radiographic Image Interpretation, Computer-Assisted; Renal Artery; Renal Circulation; Stents; Tomography, X-Ray Computed; Treatment Outcome; Vascular Patency
PubMed: 26755068
DOI: 10.1016/j.jvs.2015.10.091 -
Medical Image Analysis Jul 2020Fine renal artery segmentation on abdominal CT angiography (CTA) image is one of the most important tasks for kidney disease diagnosis and pre-operative planning. It...
Fine renal artery segmentation on abdominal CT angiography (CTA) image is one of the most important tasks for kidney disease diagnosis and pre-operative planning. It will help clinicians locate each interlobar artery's blood-feeding region via providing the complete 3D renal artery tree masks. However, it is still a task of great challenges due to the large intra-scale changes, large inter-anatomy variation, thin structures, small volume ratio and small labeled dataset of the fine renal artery. In this paper, we propose the first semi-supervised 3D fine renal artery segmentation framework, DPA-DenseBiasNet, which combines deep prior anatomy (DPA), dense biased network (DenseBiasNet) and hard region adaptation loss (HRA): 1) Based on our proposed dense biased connection, the DenseBiasNet fuses multi-receptive field and multi-resolution feature maps for large intra-scale changes. This dense biased connection also obtains a dense information flow and dense gradient flow so that the training is accelerated and the accuracy is enhanced. 2) DPA features extracted from an autoencoder (AE) are embedded in DenseBiasNet to cope with the challenge of large inter-anatomy variation and thin structures. The AE is pre-trained (unsupervised) by numerous unlabeled data to achieve the representation ability of anatomy features and these features are embedded in DenseBiasNet. This process will not introduce incorrect labels as optimization targets and thus contributes to a stable semi-supervised training strategy that is suitable for sensitive thin structures. 3) The HRA selects the loss value calculation region dynamically according to the segmentation quality so the network will pay attention to the hard regions in the training process and keep the class balanced. Experiments demonstrated that DPA-DenseBiasNet had high predictive accuracy and generalization with the Dice coefficient of 0.884 which increased by 0.083 compared with 3D U-Net (Çiçek et al., 2016). This revealed our framework with great potential for the 3D fine renal artery segmentation in clinical practice.
Topics: Computed Tomography Angiography; Humans; Image Processing, Computer-Assisted; Renal Artery; Supervised Machine Learning
PubMed: 32434127
DOI: 10.1016/j.media.2020.101722 -
Renal Artery Outcomes After Open Repair of Suprarenal or Type IV Thoraco-abdominal Aortic Aneurysms.European Journal of Vascular and... Nov 2020The aim of this study was to evaluate the mid and long term patency of elective renal artery reconstructions during open surgical repair of suprarenal aortic aneurysms...
OBJECTIVE
The aim of this study was to evaluate the mid and long term patency of elective renal artery reconstructions during open surgical repair of suprarenal aortic aneurysms (SRAA) and type 4 thoraco-abdominal aortic aneurysms (T4AAA).
METHODS
This retrospective, single centre study included all consecutive patients who underwent surgery for SRAA or T4AAA between January 2009 and December 2019 at Toulouse University Hospital. All patients underwent strict pre-operative planning with computed tomography angiography (CTA) and 3D reconstruction of the aortic aneurysm, visceral and renal artery anatomy to choose the most appropriate surgical technique for each case. Primary patency, primary assisted patency, and rates of re-intervention were calculated using the Kaplan-Meier method.
RESULTS
In total, 103 patients, having undergone 159 renal artery revascularisation procedures, were enrolled in the study. Fifty-five patients presented with a type T4AAA and 48 patients with a SRAA. In hospital mortality was 2.9%. In association with aortic surgery, 100 direct re-implantation (62.8%), 48 retrograde bypasses (30.1%), and 11 anterograde bypasses (6.9%) of the renal arteries were performed. Median follow up was 45.9 ± 36 months. Renal artery primary patency rates were 99.4%, 96.4%, and 93.1% at one, three, and five years, respectively. Assisted primary patency rates were 99.4%, 97.7%, and 97.7% at one, three, and five years, respectively, with five cases of renal stenosis > 70% successfully treated by renal stenting. No significant difference in patency was found regarding the type of renal revascularisation.
CONCLUSION
This retrospective study suggests that the mid term patency of elective open renal artery reconstruction during SRAA and type T4AAA surgery preceded by pre-operative planning with 3D-CTA reconstruction, yields excellent outcomes whatever the technique used.
Topics: Aortic Aneurysm, Abdominal; Aortic Aneurysm, Thoracic; Blood Vessel Prosthesis Implantation; Humans; Renal Artery; Retrospective Studies; Treatment Outcome
PubMed: 32888782
DOI: 10.1016/j.ejvs.2020.07.052 -
Scientific Reports Nov 2016Autonomic nervous system plays a crucial role in maintaining and regulating vessel tension. Renal denervation (RDN) may induce renal artery vasodilation by damaging...
Autonomic nervous system plays a crucial role in maintaining and regulating vessel tension. Renal denervation (RDN) may induce renal artery vasodilation by damaging renal sympathetic fibers. We conducted this animal study to evaluate whether renal artery vasodilation could be a direct indicator of successful RDN. Twenty-eight Chinese Kunming dogs were randomly assigned into three groups and underwent RDN utilizing temperature-controlled catheter (group A, n = 11) or saline-irrigated catheter (group B, n = 11) or sham procedure (group C, n = 6). Renal angiography, blood pressure (BP) and renal artery vasodilation measurements were performed at baseline, 30-minute, 1-month, and 3-month after interventions. Plasma norepinephrine concentrations were tested at baseline and 3-month after intervention. Results showed that, in addition to significant BP reduction, RDN induced significant renal artery vasodilation. Correlation analyses showed that the induced renal artery vasodilation positively correlated with SBP reduction and plasma norepinephrine reduction over 3 months after ablation. Post hoc analyses showed that saline-irrigated catheter was superior to TC catheter in renal artery vasodilation, especially for the acute dilatation of renal artery at 30-minute after RDN. In conclusion, renal artery vasodilation, induced by RDN, may be a possible indicator of successful renal nerve damage and a predictor of blood pressure response to RDN.
Topics: Angiography; Animals; Blood Pressure; Denervation; Dogs; Kidney; Norepinephrine; Random Allocation; Renal Artery; Sympathetic Nervous System; Time Factors; Vasodilation
PubMed: 27849014
DOI: 10.1038/srep37218 -
Archivio Italiano Di Urologia,... Dec 2023Radical nephrectomy for Renal Cell Carcinoma (RCC) is still the treatment of choice for all stages except for stage I and IV, which need patient selectivity. The purpose... (Meta-Analysis)
Meta-Analysis
INTRODUCTION
Radical nephrectomy for Renal Cell Carcinoma (RCC) is still the treatment of choice for all stages except for stage I and IV, which need patient selectivity. The purpose of Renal Artery Embolization (RAE) pre-operative before radical nephrectomy is to facilitate resection, reduce bleeding, and reduce the time to surgery, but the necessity of this procedure is still debatable. This study investigates the efficacy of pre-operative Renal Artery Embolization (PRAE) before radical nephrectomy for RCC patients.
METHODS
The systematic searches based on PRISMA guidelines were conducted in Pubmed, Scopus, Web of Science, Medrxiv, and ScienceDirect databases with pre-defined keywords. Both analyses, quantitative and qualitative, were performed to assess blood loss, transfusion rate, surgical time, Intensive Care Unit (ICU) stay, and hospital stay.
RESULTS
A total of 921 patients from 8 eligible studies were included. The blood loss was significantly lower in the PRAE group compared to the control group (p = < 0.00001; SMD -20 mL; 95%CI -0.29, -0.12). There is no statistically significant difference between RAE and without RAE in the transfusion rate nephrectomy (p = 0.53, OR 0.65; 95% CI 0.16, 2.57), mean operative time (p = 0.69; SMD 5.91; 95% CI -23.25, 35.07), mean length of hospital stay (p = 0.05; SMD 0.56; 95% CI 0.00, 1.12), and mean length of stay in the ICU (p = 0.45; SMD 11.61; 95% CI -18.35, 41.57) Conclusions: PRAE before radical nephrectomy significantly reduces blood loss in RCC patients but is similar in the surgical time, transfusion rate, and length of hospital stay and ICU stay.
Topics: Humans; Carcinoma, Renal Cell; Renal Artery; Kidney Neoplasms; Treatment Outcome; Retrospective Studies; Nephrectomy
PubMed: 38058293
DOI: 10.4081/aiua.2023.12018 -
Heart (British Cardiac Society) Oct 2019Improved and durable control of hypertension is a global priority for healthcare providers and policymakers. There are several lifestyle measures that are proven to...
Improved and durable control of hypertension is a global priority for healthcare providers and policymakers. There are several lifestyle measures that are proven to result in improved blood pressure (BP) control. Moreover, there is incontrovertible evidence from large scale randomised controlled trials (RCTs) that antihypertensive drugs lower BP safely and effectively in the long-term resulting in substantial reduction in cardiovascular morbidity and mortality. Importantly, however, evidence is accumulating to suggest that patients neither sustain long-term healthy behaviours nor adhere to lifelong drug treatment regimens and thus alternative measures to control hypertension warrant further investigation. Endovascular renal denervation (RDN) appears to hold some promise as a non-pharmacological approach to lowering BP and achieves renal sympathectomy using either radiofrequency energy or ultrasound-based approaches. This treatment modality has been evaluated in clinical trials in humans since 2009 but initial studies were compromised by being non-randomised, without sham control and small in size. Subsequently, clinical trial design and rigour of execution has been greatly improved resulting in recent sham-controlled RCTs that demonstrate short-term reduction in ambulatory BP without any significant safety concerns in both medication-naïve and medication-treated hypertensive patients. Despite this, the joint UK societies still feel that further evaluation of this therapy is warranted and that RDN should not be offered to patients outside of the context of clinical trials. This document reviews the updated evidence since our last consensus statement from 2014 and provides a research agenda for future clinical studies.
Topics: Clinical Trials as Topic; Humans; Radiofrequency Ablation; Renal Artery; Societies, Medical; Sympathectomy; United Kingdom
PubMed: 31292190
DOI: 10.1136/heartjnl-2019-315098