Clinical and Radiological Outcomes of Accessory Renal Artery Exclusion during Endovascular Repair of Abdominal Aortic Aneurysms.

BACKGROUND: Accessory renal arteries (ARAs) frequently coexist with abdominal aortic aneurysms (AAA) and can influence treatment. This study aimed to retrospectively analyze the ARA's exclusion effect on patients undergoing standard endovascular aneurysm repair for AAA. METHODS: The study focused on medium- and long-term outcomes, including type II endoleak, aneurysmal sac changes, mortality, reoperation rates, renal function, and infarction post-operatively. RESULTS: 76 patients treated with EVAR for AAA were included. One hundred and two ARAs were identified: 69 originated from the neck, 30 from the sac, and 3 from the iliac arteries. The ARA treatment was embolization in 15 patients and coverage in 72. Technical success was 100%. One-month post-operative computed tomography angiography (CTA) revealed that 76 ARAs (74.51%) were excluded. Thirty-day complications included renal deterioration in 7 patients (9.21%) and a blood pressure increase in 15 (19.73%). During follow-up, 16 patients (21.05%) died, with three aneurysm-related deaths (3.94%). ARA-related type II endoleak (T2EL) was significantly associated with the ARA's origin in the aneurysmatic sac. Despite reinterventions were not significantly linked to any factor, post-operative renal infarction was correlated with an ARA diameter greater than 3 mm and ARA embolization. CONCLUSION: ARAs can influence EVAR outcomes, with anatomical and procedural factors associated with T2EL and renal infarction. Further studies are needed to optimize the management of ARAs during EVAR.

Multiple variation of right renal and gonadal vascularization: report of two cases.

We present two cases of multiple anatomical variations of the renal and gonadal vessels. The first case presented duplication of the renal vein and the presence of an accessory renal artery. However, the most interesting fact, in this case, was that the right gonadal vein emptied into the inferior right renal vein instead of ending in the inferior vena cava as would typically be the case. In the second case, we also found an accessory renal artery and the right gonadal vein emptied at the exact junction between the right renal vein and the inferior vena cava. Clinicians and surgeons should be familiar with anatomical variations to provide an accurate diagnosis during preoperative studies and to avoid surprises in abdominal surgical procedures.

Este estudo apresenta dois casos de variação anatômica múltipla de vasos renais e gonadais. O primeiro caso apresentou uma duplicação da veia renal e a presença de uma artéria renal acessória. Porém, o fato mais interessante nesse caso foi a veia gonadal direita desembocar na veia renal direita inferior em vez de terminar na veia cava inferior, como seria o normal. No segundo caso, além de também encontrarmos uma artéria renal acessória, a veia gonadal direita desembocava no exato ponto de junção entre a veia renal direita e a veia cava inferior. Clínicos e cirurgiões devem estar familiarizados com a presença de possíveis variações dos vasos renais e gonadais, sendo um conhecimento imprescindível para obter um diagnóstico mais preciso e para evitar surpresas em procedimentos cirúrgicos abdominais.

Effect of Accessory Renal Arteries on Essential Hypertension and Related Mechanisms.

BACKGROUND: This case-control study aimed to determine whether there were differences between patients with essential hypertension with accessory renal arteries (ARAs) and those without ARAs. METHODS AND RESULTS: The enrolled patients with essential hypertension were divided into the ARA group (n=200) and control group without ARAs (n=238). After propensity matching, 394 patients (197 in each of the 2 groups), were included. The 24-hour BP (4.33/2.43 mm Hg) and daytime BP (4.48/2.61 mm Hg) of patients in the ARA group were significantly higher than those of the control group (P<0.05). The flow-mediated dilation was lower in the ARA group (5.98±2.70 versus 5.18±2.66; P<0.05). In correlation analysis, the horizontal plasma aldosterone concentration had the highest correlation with 24-hour, daytime, and nighttime systolic BP (r=0.263, 0.247, and 0.243, respectively; P<0.05) and diastolic BP (r=0.325, 0.298, and 0.317, respectively; P<0.05). As for multivariate regression analysis, plasma aldosterone concentration was a significant risk factor for elevated 24-hour, daytime, and nighttime systolic BP (ß=0.249 [95% CI, 0.150-0.349], 0.228 [95% CI, 0.128-0.329], and 0.282 [95% CI, 0.187-0.377], respectively; P<0.05) and elevated diastolic BP (ß=0.289 [95% CI, 0.192-0.385], 0.256 [95% CI, 0.158-0.353], and 0.335 [95% CI, 0.243-0.427], respectively; P<0.05). Direct renin concentration was also a risk factor for 24-hour and daytime BPs, whereas heart rate was a risk factor correlated with 24-hour, daytime, and nighttime diastolic BP (all P<0.05). For the mixed-effects model for repeated measures, the results were similar to results of the multivariate regression analysis (all P<0.05). CONCLUSIONS: ARAs could contribute a higher BP of patients with essential hypertension and might promote the development of essential hypertension. The mechanism might be related to overactivation of the renin-angiotensin-aldosterone system and sympathetic nervous system.

Case Series on Double-Barrel Stenting for the Renal Arteries Associated With Fenestrated Repair (FEVAR) of Complex Anatomy Aortic Aneurysms.

The double-barrel stenting (DBS) is a technique in which 2 parallel stents are simultaneously deployed through the same reinforced fenestration, into 2 adjacent target vessels. Prior reports describe the application of this technique for the treatment of superior mesenteric artery dissection with aneurysmal degeneration, coronary artery bifurcations, aortic arch branches, and intracranial aneurysms. The DBS technique is particularly useful in the context of fenestrated repair (FEVAR) of complex anatomy aortic aneurysms when the origin of visceral arteries branch off the aorta very close to each other or present early branches. We herein describe a case series including 7 patients who underwent a FEVAR procedure for thoracoabdominal and juxtarenal aortic aneurysms in which the presence of accessory renal arteries (ARA) or early renal branches was the reason for the application of this technique. Technical success was 100% and all stents were patent in the last follow-up CT scan (follow-up range: 1.8-62.8 months). There was only 1 small endoleak from indetermined source potentially related to the DBS, but the aneurysm sac decreased in size during follow-up and no secondary intervention was needed. Therefore, the DBS technique is a viable option for the incorporation of ARA or early renal branches to a fenestrated repair of aortic aneurysms with complex anatomy.

Impact of Accessory Renal Artery Embolization on Renal Deterioration Under Endovascular Aortic Repair.

OBJECTIVE: The optimal management strategy for patients with accessory renal arteries undergoing endovascular aortic repair is unclear. This study aimed to investigate the impact of accessory renal artery (aRA) embolization on postoperative renal deterioration and to identify the predictors of postoperative renal deterioration in patients who underwent endovascular aortic repair (EVAR). METHODS: A retrospective single-centre observational study was conducted at our hospital. Of 331 consecutive patients who underwent endovascular aortic repair between April 2011 and February 2021, 29 patients with an aRA were included in this study. Spearman's rank correlation coefficients of decrease in estimated glomerular filtration rate (eGFR), renal volume reduction rate, infarcted renal volume, and quantity of contrast use for postoperative renal deterioration were analyzed. The correlation coefficients of the correlations between infarcted renal volume, renal volume reduction rate, and decrease in eGFR and the rate of aRA diameter were also analyzed. Multivariable nominal logistic regression analyses were conducted to evaluate the odds of postoperative renal deterioration. RESULTS: The renal volume reduction rate and infarcted renal volume had a significant positive correlation with the decrease in eGFR. Body surface area and preoperative renal volume were significantly but negatively correlated with the decrease in eGFR. The infarcted renal volume, renal volume reduction rate, and decrease in eGFR were significantly and positively correlated with the aRA diameter. The odds ratio for decreased eGFR rate in preoperative renal volume was .96 (95% CI 0.930‒.996, P = .009). CONCLUSIONS: EVAR with aRA embolization impacts postoperative renal deterioration in patients with preoperative low renal volume, and the diameter of the embolized aRA might be a predictor of postoperative renal deterioration.

Multiple variation of right renal and gonadal vascularization: report of two cases / Variação múltipla da vascularização renal e gonadal direita: relato de dois casos

Abstract We present two cases of multiple anatomical variations of the renal and gonadal vessels. The first case presented duplication of the renal vein and the presence of an accessory renal artery. However, the most interesting fact, in this case, was that the right gonadal vein emptied into the inferior right renal vein instead of ending in the inferior vena cava as would typically be the case. In the second case, we also found an accessory renal artery and the right gonadal vein emptied at the exact junction between the right renal vein and the inferior vena cava. Clinicians and surgeons should be familiar with anatomical variations to provide an accurate diagnosis during preoperative studies and to avoid surprises in abdominal surgical procedures.

Resumo Este estudo apresenta dois casos de variação anatômica múltipla de vasos renais e gonadais. O primeiro caso apresentou uma duplicação da veia renal e a presença de uma artéria renal acessória. Porém, o fato mais interessante nesse caso foi a veia gonadal direita desembocar na veia renal direita inferior em vez de terminar na veia cava inferior, como seria o normal. No segundo caso, além de também encontrarmos uma artéria renal acessória, a veia gonadal direita desembocava no exato ponto de junção entre a veia renal direita e a veia cava inferior. Clínicos e cirurgiões devem estar familiarizados com a presença de possíveis variações dos vasos renais e gonadais, sendo um conhecimento imprescindível para obter um diagnóstico mais preciso e para evitar surpresas em procedimentos cirúrgicos abdominais.

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.

Reconstruction of the accessory renal artery with autogenous vessels in aortic hybrid surgery: A case report.

OBJECTIVE: Accessory renal artery (ARA) is a common variant of renal vessels. Currently, there are some controversies about reconstruction strategy and few cases reported in the literature. Individualized treatment should be carried out according to preoperative renal function evaluation and technical level. METHODS: In this paper, a 50-year-old male patient was reported, who developed a dissecting aneurysm after thoracic endovascular aortic repair (TEVAR) and needed further intervention. Imaging showed that the left kidney was supplied by bilateral renal artery (false lumens), and there were left renal malperfusion complicated with abnormal renal function. RESULTS: Autologous blood vessels were used to successfully reconstruct ARA with during hybrid surgery. Renal perfusion and renal function recovered rapidly after operation. There was no abnormality in renal indexes after 3 months follow-up. CONCLUSION: It is beneficial and necessary to reconstruct ARA for patients with renal malperfusion or abnormal renal function before operation.

Reversed and Antegrade Iliac Side Branch Stentgraft as an Alternative or Rescue Maneuver in Complex (Thoraco)Abdominal Endovascular Aortic Repair to Preserve Renal Perfusion.

PURPOSE: To describe a technique that can preserve renal perfusion in failed bridging stent implantation of renal arteries or as intentional procedure in emergency cases, when the (thoraco)abdominal aneurysm anatomy does not meet the criteria for instructions for use of an "off-the-shelf" graft. The technique is based on reversed or antegrade integration of a standard iliac side branch graft into the aortic stentgraft system, which allows cannulation of (accessory) renal vessels. TECHNIQUE: A standard iliac side branch prosthesis is deployed and re-sheathed in reversed direction on the back table. The endograft is then implanted in the unibody in analogy to an iliac limb. The iliac side branch is cannulated followed by target vessel cannulation and covered bridging stents are deployed for completion. Furthermore, an iliac side branch prothesis can also be used to preserve relevant accessory renal arteries, when implanted in delivered antegrade loading position. CONCLUSION: The use of a reversed and antegrade iliac side branch technique to revascularize renal vessels is feasible and safe in selected patients. This technique may also allow to extend the range of an "offthe- shelf" (multibranch) stentgraft, when immediate treatment is required.

Off-the-Shelf Strategy for Endovascular Aneurysm Repair of Ectopic, Dominant, Renal Artery Originating From the Aortic Bifurcation: Case Report.

INTRODUCTION: An ectopic renal artery originating from the aortic bifurcation can strongly interfere with surgical or endovascular intervention in the infrarenal aorta. CASE: We present an infrarenal symptomatic aneurysm with a right ectopic/pelvic kidney associated with 1 renal artery originating from the aortic bifurcation. RESULT: During an endovascular aortic repair (EVAR) procedure, the dominant ectopic right kidney was perfused by an iliac branch device (IBD) used as an iliac extension. However, out of instructions for use (IFU), this is an "off-the-shelf" resolution for this type of rare case. CONCLUSION: The use of an "off-the-shelf" IBD to perform an EVAR with an ectopic renal artery, in patients unfit for open surgery, is a potentially valuable option.

Ectopic vascularization of the right kidney arising from contralateral common iliac artery.

BACKGROUND: Variant renal arteries have been reported in 20~30% of the entire population. The anatomic variations among advanced patients should be investigated when performing surgery or interventional procedures on the kidney. Most variant renal arteries originated from various level of the abdominal aorta. Very rarely, this case shows renal artery originated from the contralateral common iliac artery with other accessory arteries. CASE PRESENTATION: MDCT angiography revealed several anatomical variants of the right kidney. There were four right renal arteries. The main renal artery originated from the left proximal common iliac artery and other renal artery originated from the aortic bifurcation. The other two renal arteries arose from the abdominal aorta, lower thoracic T12 level and lower lumbar L4 level. The right kidney was located at the level of the third to fifth lumbar vertebra. And renal pelvis of the right kidney was laterally rotated. CONCLUSION: This case documented a rare anatomic variant, involving multiple accessory renal arteries, including the main artery originating from the contralateral iliac artery, caused by a specific renal embryological condition. These variants should be analysed to effectively perform surgical and interventional procedures.

Patient Selection for Renal Denervation in Hypertensive Patients: What Makes a Good Candidate?

Renal denervation (RDN) as a therapeutic intervention in patients with hypertension has been intensively studied for over a decade, yet a critical question remains unanswered: what kind of patients are the ideal target population for RDN to achieve its maximum clinical benefit? We herein provide a review of current literature to answer questions related to patient selection to identify populations that will benefit most from RDN, drawing first from human studies but also important clues derived from preclinical animal models. Different aspects that may influence the selection of patients such as the cause of hypertension, the severity of hypertension, concurrent pharmaceutical treatment, renal function, and renal artery anatomy are discussed. Based on current evidence, patients who have severe primary hypertension, regardless of medication or degree of renal dysfunction, who have an accessible accessory renal artery, can achieve a desirable response if a thorough ablation is achieved. In preclinical models, as in humans, RDN shows variable impact, with evidence indicating it does not work in specific conditions such as reduced renal mass, salt-sensitive hypertension, and autosomal recessive polycystic kidney disease. The thresholds, however, for indicators are such that it is still not possible to reliably predict which patients could benefit from the technique. Confirmation of predictive factors and identification of biomarkers are needed before RDN can be integrated in clinical practice on clear and reliable grounds.

The preservation of accessory renal arteries should be considered the treatment of choice in complex endovascular aortic repair.

OBJECTIVE: The objective of this study was to evaluate renal function and renal parenchymal length changes secondary to the coverage or preservation of accessory renal arteries (ARAs) in complex aortic repair. METHODS: This was a single-center retrospective study identifying all patients undergoing fenestrated or branched endovascular aortic repair (f-b EVAR) who presented with ARAs. Two groups were created, a preserved ARA group, with incorporation of the vessel as a dedicated fenestration or branch in the endograft plan, and a non-preserved ARA group, without incorporation of them. Early >30% decline of glomerular filtration rate (GFR), kidney infarcts, and endoleaks were evaluated. Mid-term results with freedom from kidney shrinkage (defined as length decrease >10%) at follow-up, freedom from GFR decrease >30%, or need for postoperative dialysis at follow-up were also analyzed. Primary assisted patency of incorporated ARAs was calculated. RESULTS: From 2011 through 2020, 145 patients undergoing complex aortic repair presented with an ARA. After excluding ruptured aneurysms, 33 patients had the ARA preserved with their incorporation into the stent graft (preserved ARA group), and 99 did not have preservation of them (not-preserved ARA group). There were no statistical differences in demographics or type of aneurysm. Patients in the ARA-preserved group had more ARAs (median of two per patient vs one in the non-preserved ARA group; P = .01) and bigger ARAs (median 4 vs 3 mm in the non-preserved ARA group; P = .001). Early postoperative worsening >30% of GFR (23% vs 6%; P = .03) as well as postoperative renal infarction (57% vs 6%; P = .001) and ARA-related endoleaks (20% vs 0%; P = .01) were statistically higher for the not-preserved ARA group. Mid-term kidney length showed significant shrinkage in the not-preserved ARA group compared with the ARA preserved group (9.7% vs 0%; P = .001). Freedom from >30% GFR decline at 2 years was significantly higher for the preserved ARA group (83% vs 47%; P = .01).Two-year primary assisted patency of incorporated ARA was 94%. CONCLUSIONS: Complex aortic repair incorporation of ARA is feasible, with low complications and good primary assisted patency at 2 years. It leads to less postoperative early renal dysfunction as well as higher freedom for mid-term renal disfunction and kidney shrinkage.

Reconstruction of a Lower Polar Artery for Kidney Transplantation Using Donor Ovarian Vein: Case Report with Literature Review.

Background: In the case of complicated kidney transplantation, when the accessory artery is severed, the main task is to decide whether to restore renal blood flow and which method should be used. In this report, we present a case of kidney transplantation with vascular reconstruction using an ovarian vein as an interposition graft between a larger branch of the main renal artery and the lower polar artery which was severed during kidney explantation. Case summary: Kidney transplantation using an ovarian vein was performed for a 34-year-old woman with end-stage renal disease on 1 April 2020 in the Hospital of Lithuanian university of health sciences (LUHS) Kaunas Clinics. A lower accessory renal artery was severed during kidney explantation. As the ovarian vein of the donor remained and matched the diameter of the severed vessel, it was decided to use it as an insertion between the main renal artery and the accessory renal artery of the inferior pole. The cold ischemic time was 770 min and the warm ischemic time was 37 min. A month after transplantation, the patient's condition and daily urine output were normal and the serum creatinine level decreased rapidly. Fifteen months after the surgery, the function and structure of the transplant remained normal and there was no evidence of serious vascular complications on CT scans. This is the first case where graft function was verified after transplantation using three-dimensional CT angiography. Conclusions: If an inferior polar artery is severed, vascular reconstruction must be performed to preserve the function of the graft. Usually, the gonadal vein is available during donor nephrectomy; therefore, it can be explanted without additional difficulties or incisions. Although we have not reported any complications, further studies are recommended on the long-term outcomes of this alternative approach for the reconstruction of short renal arteries.

Common trunk of the right accessory renal artery and right inferior phrenic artery originating from the thoracic artery: An unreported variation.

Accessory renal arteries (ARAs) are common and usually originate from the abdominal aorta and the renal artery. Inferior phrenic arteries (IPAs) can also arise from the abdominal aorta or its branches. In this paper, we present the first case of a common trunk of the right ARA and right IPA arising from the thoracic artery at the level of T10, which was discovered by multidetector-row computed tomography in pretherapeutic evaluation and clearly confirmed by selective angiography. It is important to recognize this anatomical variation when performing cardiovascular and interventional radiological procedures.

Implicaciones clínicas de la variante accesoria de arteria renal. Revisión sistemática de la literatura / Clinical implications of the accessory renal artery. A systematic literature review

Resumen Objetivo: Establecer las posibles implicaciones clínicas y quirúrgicas asociadas a la presencia de arterias renales accesorias y su relación con desenlaces relevantes para la salud como la hipertensión arterial sistémica resistente y el rechazo agudo de trasplantes renales. Material y métodos: Revisión sistemática de la literatura registrada en International Prospective Register of Systematic Reviews. Cuatro autores cegados realizaron su búsqueda de 2008 a 2018, según criterios de inclusión, términos y combinaciones prestablecidos, en cinco bases de datos y gestor de referencias bibliográficas Zotero, evaluación de calidad con la herramienta Study Quality Assessment Tools, del National Heart, Lung, and Blood Institute y cálculo de índice Kappa. Resultados: 32 estudios seleccionados, superaron el mínimo de puntuación en la evaluación de la calidad metodológica, revelando bajo riesgo de sesgo. El grado de acuerdo entre los revisores, fue de 0.81-1.0, interpretado como concordancia, casi perfecta. Las características de los estudios, según el año de publicación fue considerable para los años 2013 y 2009. La mayoría de los estudios fueron realizados en Estados Unidos, seguido de otros países. Como desenlaces se encontraron seis estudios para Hipertensión arterial sistémica y 26 para Trasplante renal. Conclusiones: La presencia de arterias renales accesorias es una de las posibles causas a valorar en pacientes hipertensos con refractariedad al tratamiento convencional. Por su parte, la incidencia de rechazo y pérdida de viabilidad post trasplante renal se aproxima al 20% en pacientes con arterias renales accesorias y se asocia con complicaciones urológicas o sistémicas.

Abstract Objective: To establish some of the possible surgical and clinical implications related to the presence of accessory renal arteries and their relationship with relevant health outcomes like resistant systemic hypertension and acute rejection of renal transplantation. Methods: Systematic review of the literature registered in the International prospective register of systematic reviews. Four blinded authors carried out their search from 2008 to 2018, according to the inclusion criteria, pre-established terms, and combinations, in five databases and the Zotero bibliographic reference manager, quality assessment with the Study Quality Assessment Tools, from the National Heart, Lung, and Blood Institute, and calculation of Kappa indices. Results: 32 selected studies exceeded the minimum score in the assessment of methodological quality, revealing a low risk of bias. The degree of agreement between the reviewers was 0.81-1.0, interpreted as almost perfect concordance. The characteristics of the studies, according to the year of publication, were considerable for the years 2013 and 2009. Most of the studies were carried out in the United States, followed by other countries. Based on the outcomes, the following studies were found, six for systemic arterial hypertension and 26 for kidney transplantation. Conclusions: The presence of accessory renal arteries is one of the possible causes when assessing hypertension patients with refractoriness to conventional treatment. For its part, incidence of acute rejection and post-transplantation loss of viability are near 20% in patients treated with accessory renal arteries; it is associated with urological and systemic complications.

Clinical effect of accessory renal artery coverage after endovascular repair of aneurysms in abdominal and thoracoabdominal aorta.

BACKGROUND: The aim of our systematic review and meta-analysis was to assess the effect of accessory renal artery (ARA) coverage on renal function in terms of acute kidney injury (AKI), renal infarction, chronic renal failure (CRF), and mortality in patients undergoing standard endovascular aortic aneurysm repair (EVAR) or endovascular repair of complex aneurysms. METHODS: An electronic search of the English language medical literature from 2000 to September 2020 was conducted using the MEDLINE, EMBASE, and Cochrane databases with the PRISMA (preferred reporting items for systematic reviews and meta-analyses) method for studies reporting on ARA management in patients undergoing endovascular repair of aneurysms in the abdominal and thoracoabdominal aorta. The patients were divided into two groups: group 1, patients with ARA coverage; and group 2, patients without an ARA or without coverage of the ARA. Each group included two arms, one of patients who had undergone standard EVAR and one of patients who had undergone endovascular treatment of a complex aortic aneurysm. The GRADE (grading of recommendations assessment, development, evaluation) approach was used to evaluate the quality of evidence and summary of the findings. The primary outcomes included the incidence of AKI, renal infarction, CRF, and mortality. RESULTS: Ten retrospective, nonrandomized, control studies were included in the systematic review reporting on 1014 patients (302 with a covered ARA vs 712 without an ARA or without ARA coverage). In six studies, the mean diameter of the covered ARA was <4 mm (range, 2.7-3.4 mm). The mean follow-up was 22.74 months (range, 1-42 months). In the standard EVAR subgroup, the risk of AKI (odds ratio [OR], 0.72; 95% confidence interval [CI], 0.21-2.51; I2 = 0%] in the early period, and CRF (OR, 4.44; 95% CI, 0.46-42.61; I2 = 87%) and death (OR, 0.91; 95% CI, 0.36-2.31; I2 = 0%) during follow-up were similar between groups 1 and 2. Only the risk of renal infarction was greater in group 1 than in group 2 (OR, 93.3; 95% CI, 1.48-5869; I2 = 92%). In the complex aneurysm repair subgroup, the risk of AKI (OR, 1.85; 95% CI, 0.61-5.64; I2 = 42%) in early period and CRF (OR, 1.64; 95% CI, 0.88-3.07; I2 = not applicable) and death (OR, 3.63; 95% CI, 0.14-96.29; I2 = 56%) during follow-up were similar between groups 1 and 2. Only the risk of renal infarction was greater for group 1 compared with group 2 (OR, 8.58; 95% CI, 4.59-16.04; I2 = 0%). CONCLUSIONS: ARA (<4 mm) coverage in patients undergoing standard EVAR or endovascular repair of complex aneurysms is associated with an increased risk of renal infarction. However, we found no clinical effects of ARA coverage on renal function or mortality in early postoperative and follow-up period. Preservation of an ARA >4 mm should be considered.

Renal Volumetry-based Prediction of the Presence of Accessory Renal Artery: Computed Tomographic Angiography-based Study with Clinical Implications on Renal Doppler.

BACKGROUND: The objective was to validate the hypothesis and evaluate whether the presence or absence of accessory renal artery can be predicted on the basis of volumetric parameters of kidney and diameter of the main renal artery (mRA). METHODS: This retrospective analysis was performed in a total of 60 kidneys in 30 patients, who had computed tomographic (CT) angiography. The kidneys were segregated into control and study groups depending on the absence or presence of accessory renal artery. The total renal volumes were measured using renal length, breadth, and height in mm3. The renal artery diameters were also measured in mm, in the postostial segment. Renal volume/renal artery diameter (V/d) was measured for each kidney in two groups, and the difference in mean V/d values (in mm2) in two groups was measured for statistical significance. RESULTS: The mean V/d value in the study group with presence of the accessory renal artery was found to be 23,444.7 mm2 (range: 16,229.1-32,490.0). The V/d value in the control group with the absence of accessory renal artery was found to be 19,717.15 mm2 (range: 13,704.6-28,000.0). The mean values in the two groups showed a statistically significant difference in the V/d with a P value of 0.001 (P < 0.05). CONCLUSION: The study suggests that the possibility of the presence of the accessory renal artery is directly proportional to the total renal volume and inversely proportional to the diameter of mRA. The use of integrated volumetric parameter (V/d) is therefore likely to play a key role in the prediction of the presence of accessory renal artery on imaging studies. Renal volumetry on CT angiography may help predict the presence of accessory renal artery and thus may have implications on renal Doppler studies.

Comprehensive Assessment of Human Accessory Renal Artery Periarterial Renal Sympathetic Nerve Distribution.

OBJECTIVES: The aim of this study was to understand the anatomy of periarterial nerve distribution in human accessory renal arteries (ARAs). BACKGROUND: Renal denervation is a promising technique for blood pressure control. Despite the high prevalence of ARAs, the anatomic distribution of periarterial nerves around ARAs remains unknown. METHODS: Kidneys with surrounding tissues were collected from human autopsy subjects, and histological evaluation was performed using morphometric software. An ARA was defined as an artery arising from the aorta above or below the dominant renal artery (DRA) or an artery that bifurcated within 20 mm of the takeoff of the DRA from the aorta. The DRA was defined as an artery that perfused >50% of the kidney. RESULTS: A total of 7,287 nerves from 14 ARAs and 9 DRAs were evaluated. The number of nerves was smaller in the ARA than DRA (median: 30 [interquartile range: 17.5 to 48.5] vs. 49 [interquartile range: 36 to 76]; p < 0.0001). In both ARAs and DRAs, the distance from the arterial lumen to nerve was shortest in the distal, followed by the middle and proximal segments. On the basis of the post-mortem angiography, ARAs were divided into large (≥3 mm diameter) and small (<3 mm) groups. The number of nerves was greatest in the DRA, followed by the large and small ARA groups (53 [41 to 97], 38 [25 to 53], and 24.5 [10.5 to 36.3], respectively; p = 0.001). CONCLUSIONS: ARAs showed a smaller number of nerves than DRAs, but these results were dependent on the size of the ARA. Ablation, especially in large ARAs, may allow more complete denervation with the potential to further reduce blood pressure.

Impact of intentional accessory renal artery coverage on renal outcomes after fenestrated-branched endovascular aortic repair.

OBJECTIVE: The objective of this study was to evaluate the impact of intentional coverage of accessory renal arteries (ARAs) on renal outcomes after fenestrated-branched endovascular aortic repair (FB-EVAR) for pararenal aortic aneurysms or thoracoabdominal aortic aneurysms. METHODS: We analyzed the clinical data of 296 patients enrolled in a prospective nonrandomized study to evaluate outcomes of FB-EVAR between 2013 and 2018. Patients with solitary kidneys, intraoperative loss of main renal arteries, or pre-existing stage V chronic kidney disease were excluded. Two groups were analyzed: patients with intentional ARA coverage; and controls, who had complete preservation. End points included 30-day mortality; major adverse events; acute kidney injury (AKI), defined by RIFLE criteria (Risk, Injury, Failure, Loss of kidney function, and End-stage renal disease); renal function deterioration (RFD), defined by >30% decline in baseline estimated glomerular filtration rate; and presence of renal infarcts. RESULTS: There were 254 patients (184 male; mean age, 75 ± 8 years) included in the study, 56 (22%) with intentional ARA coverage and 198 controls, of whom 16 had ARA preservation. ARA diameter was smaller in patients who had intentional coverage vs preservation (2.7 ± 0.9 mm vs 3.4 ± 0.2 mm; P < .001). There was no difference in demographics, cardiovascular risk factors, and aneurysm extent. All ARAs intended to be incorporated were successfully stented. Patients with ARA coverage had a higher frequency of kidney infarction (75% vs 25%; P < .001). There were two (1%) deaths within 30 days, both among controls. Patients with ARA coverage had more major adverse events (32% vs 19%; P = .04) because of higher incidence of AKI (21% vs 9%; P = .02). None of the 16 patients who had ARA preservation developed AKI. At 3 years, freedom from RFD was lower for patients who had ARA coverage compared with controls (55% ± 9% vs 76% ± 5%; log-rank, P = .02). By multivariate analysis, predictors of AKI were ARA coverage (odds ratio, 2.8; 95% confidence interval [CI], 1.2-6.2; P = .01) and estimated blood loss >1 L (odds ratio, 3.8; 95% CI, 1.2-12.3; P = .03). Postoperative AKI (hazard ratio [HR], 4.4; 95% CI, 2.4-8.1; P < .001), renal reintervention for stenosis (HR, 3.2; 95% CI, 1.6-6.7; P = .002), aneurysm diameter (HR, 1.04; 95% CI, 1.02-1.06; P < .001), and ARA coverage (HR, 2.0; 95% CI, 2.4-8.1; P = .02) were predictors of RFD. CONCLUSIONS: Intentional ARA coverage during FB-EVAR was associated with a threefold increase in AKI and with lower freedom from RFD. Factors associated with RFD included postoperative AKI, renal reinterventions for stenosis, and ARA coverage. Incorporation of ARAs during FB-EVAR, when it is technically feasible, helps decrease risk of AKI and RFD.