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

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.

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 (β=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 (β=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.

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.

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.

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

OBJECTIVE

To evaluate renal function and renal parenchymal length changes secondary to the coverage or preservation of accessory renal arteries (ARA) in complex aortic repair.

METHODS

Single-center retrospective study identifying all patients undergoing fenestrated or branched endovascular aortic repair (f-b EVAR) who present ARA. 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 (EL) 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 ARA was calculated.

RESULTS

From 2011-2020, 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 stentgraft (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 ARA (median of 2 per patient vs 1 in the non-preserved ARA group, p 0,01) and bigger ARA (median 4 vs 3 mm in the non-preserved ARA group, p 0,001).Early postoperative worsening >30% of GFR (23 vs 6%, p 0,03) as well as postoperative renal infarction (57% vs 6%, p 0,001) and ARA-related EL (20 vs 0%, p 0,01) were statistically higher for the not-preserved ARA group.Mid-term kidney length showed significant shrinkage in the not-preserved ARA group compared to the ARA preserved group (9,7 vs 0%, p 0,001). Freedom from >30% GFR decline at 2 years was significantly higher for the preserved ARA group (83% vs 47%, p 0,01).Two-years primary assisted patency of incorporated ARA was 94%.

CONCLUSIONS

In 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.

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.

Post-Traumatic Ostial Avulsion of a Polar Inferior Renal Artery Treated by Endovascular Covered Aortic Stenting

Renovascular traumas are rare in abdominal blunt traumas, especially those involving complete avulsion of a renal artery. Their management poses a dilemma between blood flow preservation and the risks of bleeding. We present the case of a rare variant of renovascular injury, with a post traumatic ostial avulsion of a polar inferior renal artery, successfully treated percutaneously by endovascular aortic covered stenting under c-arm cone-beam computed tomography guiding.

Incidence of variations in human cadaveric renal vessels

BACKGROUND

Awareness of discrepancies of renal vasculature is crucial for some medical procedures. The present study investigated origin and course of aberrant and accessory renal vessels and any associated variations.

MATERIALS AND METHODS

Renal blood vessels of 63 cadavers were examined. Number of renal veins and arteries, arrangement, location where the vasculature attached to the kidneys, and presence of variations were recorded. Incidence of renal vasculature variations was determined, and associations were tested with age at death, sex, and cause of death and whether variations were more common on a specific side.

RESULTS

Variations were found in 7 (11%; 95% confidence interval [CI] 5-22%) cadavers. For renal veins, double, triple, and quadruple veins unilaterally (5; 8%) and veins that drained the superior pole (1; 2%) or inferior pole only (5; 8%) were found. For renal arteries, double and triple arteries unilaterally (3; 5%) and arteries attached to the superior pole only (1; 2%) or inferior pole only (2; 3%) were found. Other variations (polycystic kidney, variations in the common iliac or gonadal veins) were observed. Only renal failure as a cause of death was different between those with or without variations (4/7 [57%] vs. 1/56 [2%]; p < 0.001).

CONCLUSIONS

The present study found many variations in renal vasculature. Awareness of such variations may be useful for physicians concerned with this region.

Two Stage Complex Embolization of an Arteriovenous Fistula between the Right Common Iliac Artery and the Inferior Vena Cava

We present an interesting case of a symptomatic high flow AV fistula between the right common iliac artery (CIA) and the inferior vena cava (IVC), successfully treated by endovascular coil embolization. The patient was found to have a right lower polar renal artery crossing the ipsilateral ureter arising from the CIA, causing pelvi-ureteric junction (PUJ) obstruction and recurrent pyelonephritis. It is hypothesized that this fistula arising from the lower polar renal artery and entering the IVC, may have occurred as a result of trauma during a previous pyeloplasty, or a pathologically induced process of angiogenesis stemming from recurrent pyelonephritis.