Outcomes of accessory renal artery occlusion during endovascular aneurysm repair

A type II endoleak from an accessory renal artery treated with laser assisted, transgraft coil embolization: A case report

The main complications of coverage accessory renal artery (ARA) are renal infarction and potentially renal function impairment and type II endoleak if firm apposition to the aortic wall is not achieved. We describe the management of an ARA type II endoleak treated by laser-assisted, transgraft coil embolization (LATE). A 76-year-old patient underwent a computed tomography scan 4 years after endovascular aneurysm repair. The computed tomography scan showed an increase of sac diameter with type II endoleak originating from the left ARA as an effect of aortic neck dilatation. ARA embolization was performed successfully via fusion-guided laser in situ fenestration and standard coil placement.

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.

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.

Development of an Artificial Intelligence Tool for Intraoperative Guidance During Endovascular Abdominal Aortic Aneurysm Repair

BACKGROUND

Adverse events during surgery can occur in part due to errors in visual perception and judgment. Deep learning is a branch of artificial intelligence (AI) that has shown promise in providing real-time intraoperative guidance. This study aims to train and test the performance of a deep learning model that can identify inappropriate landing zones during endovascular aneurysm repair (EVAR).

METHODS

A deep learning model was trained to identify a "No-Go" landing zone during EVAR, defined by coverage of the lowest renal artery by the stent graft. Fluoroscopic images from elective EVAR procedures performed at a single institution and from open-access sources were selected. Annotations of the "No-Go" zone were performed by trained annotators. A 10-fold cross-validation technique was used to evaluate the performance of the model against human annotations. Primary outcomes were intersection-over-union (IoU) and F1 score and secondary outcomes were pixel-wise accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV).

RESULTS

The AI model was trained using 369 images procured from 110 different patients/videos, including 18 patients/videos (44 images) from open-access sources. For the primary outcomes, IoU and F1 were 0.43 (standard deviation ± 0.29) and 0.53 (±0.32), respectively. For the secondary outcomes, accuracy, sensitivity, specificity, NPV, and PPV were 0.97 (±0.002), 0.51 (±0.34), 0.99 (±0.001). 0.99 (±0.002), and 0.62 (±0.34), respectively.

CONCLUSIONS

AI can effectively identify suboptimal areas of stent deployment during EVAR. Further directions include validating the model on datasets from other institutions and assessing its ability to predict optimal stent graft placement and clinical outcomes.

Acute Kidney Injury and Mortality After Fenestrated Endovascular Aortic Repair

INTRODUCTION

Acute kidney injury (AKI) is a common complication following endovascular aortic repair (EVAR). An association of AKI with patient survival after fenestrated EVAR (FEVAR) is currently under investigation.

METHODS

Patients undergoing FEVAR between April 2013 and June 2020 were included in the study. AKI was defined according to acute kidney injury network criteria. Demographic and perioperative data, complications, and survival are reported for the study cohort. The data were analyzed to identify possible predictors of AKI.

RESULTS

Two hundred and seventeen patients underwent FEVAR during the study period. Survival at last follow-up (20.4 ± 20.1 mo) was 75.1%. Thirty patients experienced AKI (13.8%). Six of 30 patients with AKI (20%) died within 30 days or in-hospital and 1 (3.3%) progressed to hemodialysis. Within 1 y, renal function had recovered in 23 patients (76.7%). In-hospital mortality was higher in patients with AKI (20% versus 4.3%, P = 0.006). A higher rate of AKI was seen in patients in whom an intraoperative technical complication had been documented (38.5% versus 8.4%, P = 0.001).

CONCLUSIONS

Patients undergoing FEVAR are at risk of developing AKI, especially if they experience technical intraoperative complications. Most patients see recovery of renal function within the first 30 days to 1 y, but AKI remains associated with significantly increased in-hospital mortality.

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.

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.

Isolated iliac artery aneurysm in association with congenital pelvic kidney treated with iliac branch device: case report

Background

Association of abdominal aortic aneurysm with congenital pelvic kidney is rare and association with isolated iliac artery aneurysm is not yet described in the literature.

Case presentation

We present a case of successful repair of an isolated common iliac artery aneurysm associated with a congenital pelvic kidney treated by an endovascular technique. A 75-year-old man was referred for the treatment of an asymptomatic left common iliac artery aneurysm. A computed tomography angiography revealed an isolated left common iliac artery aneurysm and a left pelvic kidney. The maximum diameter of the aneurysm was 32 mm. The congenital pelvic kidney was supplied by three small superior polar arteries that emerged from the proximal non-aneurysmal portion of the common iliac artery and the main artery that arose from the left internal iliac artery. The aneurysm exclusion was accomplished by using an iliac branch device (Gore Excluder Iliac Branch, Flagstaff, AZ). The 1 and 6 months computed tomography angiography after the procedure demonstrated complete exclusion of the aneurysm and preservation of all renal arteries.

Conclusion

Treating patients with an association of iliac artery aneurysms and pelvic kidneys can be a challenge due the variable arterial anatomy. The use of iliac branch device is a safe and effective alternative in selected cases.

Risk of renal failure and death when renal arteries are involved in endovascular aortic aneurysm repair

OBJECTIVE

Endovascular abdominal aortic repair can involve the incorporation of renal arteries. Revascularization after intentional or unintentional renal artery (RA) coverage is not always technically successful, and the loss of a single RA may result in the need for postoperative dialysis. Thus, we compared the outcomes after endovascular aneurysm repair (EVAR) stratified by RA involvement (RAI).

METHODS

Patient data from the Vascular Quality Initiative from 2009 to 2018 registry were analyzed. The exclusion criteria were preoperative dialysis, missing RAI data, and repair above the superior mesenteric artery. The repair type cohorts were defined as (1) no RAI (NRAI), (2) RAI with revascularization (RAI-R), and (3) RAI with no revascularization (RAI-NR). A sensitivity analysis was performed by excluding ruptured presentations. The primary outcome was the need for postoperative dialysis. The secondary outcomes were 30-day mortality, dialysis at follow-up, postoperative renal function, and 2-year survival. Multivariate analysis was used to determine the independent predictors for postoperative dialysis. The 2-year survival analysis was performed using Kaplan-Meier log-rank test.

RESULTS

Of 54,020 patients in the EVAR and TEVAR (thoracic EVAR)/complex EVAR modules in the Vascular Quality Initiative, 25,724 met the criteria for inclusion (NRAI, n = 24,879; RAI-R, n = 733; RAI-NR, n = 112). The demographics and comorbidities were similar among the three groups. The RAI-NR group had more frequently had ruptured or symptomatic aneurysms. The postoperative dialysis requirement was higher in the RAI-NR group (NRAI, 0.7%; RAI-R, 2.2%; RAI-NR, 17%; P < .0001), as were the 30-day mortality and dialysis requirement at follow-up. On multivariate analysis, RAI-R (odds ratio [OR], 2.2; P = .03) and RAI-NR (OR, 5.9; P < .0001) were independent predictors of postoperative dialysis and remained so after excluding ruptured presentations (RAI-R: OR, 3; P = .003; RAI-NR: OR, 22.3; P < .0001). Other independent predictors of the need for postoperative dialysis were worse preoperative renal function, a symptomatic presentation, any preoperative or intraoperative blood transfusion, and larger blood loss (≥200 mL). Excluding those with rupture, the overall survival at 2 years on Kaplan-Meier analysis was lower for the RAI-NR group (NRAI, 92%; RAI-R, 89%; RAI-NR, 80%; P = .004).

CONCLUSIONS

RAI is highly predictive of the need for postoperative and permanent dialysis after EVAR. RAI-NR was associated with lower overall survival. These risks should be considered when planning and performing EVAR and should be weighed against the risks of open repair when considering the treatment options.

Impact of Accessory Renal Artery Coverage on Renal Function during Endovascular Aortic Aneurysm Repair

BACKGROUND

Long-term outcomes of accessory renal artery (ARA) coverage after endovascular aneurysm repair (EVAR) are unknown. We analyzed the impact of ARA coverage on renal function long-term.

METHODS

This retrospective, monocentric study included patients treated by EVAR between 2008 and 2016. Patients with at least one ARA covered with EVAR (ARA group) were compared with patients with no covered ARA (control group). Renal function was determined by estimating the glomerular filtration rate (eGFR) and graded according to chronic kidney disease (CKD) classification stages.

RESULTS

A total of 184 patients were included (ARA group, n = 25; control group, n = 159). Renal risk factors were similar in the 2 groups. Mean (±standard deviation) duration of follow-up was 41.6 ± 25.8 months. Preoperative eGFR (mL/min/1.73 m²) was 68.9 ± 17.8 in the ARA group and 72.5 ± 17.4 in the control group (P = 0.33), with a similar decline in the 2 groups during follow-up (-6.52 ± 11.6 ARA group vs. -6.43 ± 13.8 control group; P = 0.97). At the end of the study, 8 ARA patients and 56 controls had deteriorated by one CKD stage (32% vs. 35.2%, respectively; P = 0.75). Rate of renal infarction was significantly higher in the ARA group (96% vs. 1.9%; P < 0.0001). In multivariate analysis, suprarenal fixation was identified as a risk factor for a decline in renal function (odds ratio = 2.01 [95% confidence interval: 1.05-3.84]; P = 0.04).

CONCLUSIONS

ARA coverage after EVAR does not appear to affect renal function long-term. Suprarenal fixation led to a greater decline in renal function.

Atypical Renal Artery Preservation with an Iliac Branch Device in an Infrarenal Abdominal Aortic Aneurysm

Anatomical variations of the renal arteries may complicate endovascular repair of infrarenal abdominal aortic aneurysms (AAA). Occlusion of renal branches may be necessary to seal the aneurysm sac efficiently. Depending on the size of the affected renal arteries and the supplied parenchyma, this can lead to loss of renal function. Iliac branch devices (IBDs) have been created in order to preserve the internal iliac artery in aortoiliac or isolated iliac aneurysms; however, IBDs have the potential to maintain patency of other arteries as well. This case report describes the off-label use of an IBD inside the main body of a bifurcated endoprosthesis in a patient with an AAA and multiple renal arteries in order to preserve the main renal artery that emerges directly out of the aneurysm sac. Special considerations such as limited craniocaudal dimensions for endoprosthesis placement and the reduced vascular space are discussed.

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.

Outcomes of Small Renal Artery Targets in Patients Treated by Fenestrated-Branched Endovascular Aortic Repair

OBJECTIVE

The aim was to evaluate renal related outcomes in patients who had incorporation of a small (<4.0 mm) renal artery (RA) during fenestrated-branched endovascular aortic repair (F-BEVAR).

METHODS

A total of 215 consecutive patients enrolled in a prospective F-BEVAR trial were reviewed. Computed tomography angiography centreline of flow reconstruction was used to measure mean RA diameter. Patients who had at least one <4.0 mm main or accessory RA incorporated by fenestration or directional branch (study group) were compared with patients who had incorporation of two ≥5.0 mm RAs (control group). Endpoints were technical success of RA incorporation, RA rupture and kidney loss, primary and secondary RA patency, RA branch instability and re-interventions, and renal function deterioration.

RESULTS

Twenty-four patients with 28 <4.0 mm RAs (16 accessory and 12 main RAs) were compared with 144 patients with 288 ≥5.0 mm incorporated RAs. Study group patients were significantly younger than controls (72 ± 8 vs. 75 ± 8 years, p = .04) and more often females (46% vs. 21%, p = .018); there were no differences in cardiovascular risk factors and aneurysm extent. Technical success was 92% for <4.0 mm and 99% for ≥5.0 mm RA incorporation (p = .05). Inadvertent RA rupture occurred in three patients in the study group (13%) and in one (1%) in the control group (p = .009) resulting in kidney loss in two study group patients (8%) and one (1%) control group patient (p = .05). At one year, primary patency was 79 ± 9% vs. 94 ± 1% (p < .001) and secondary patency was 84 ± 8% vs. 97 ± 1% (p < .001) for study vs. control group; freedom from branch instability was 79 ± 9% vs. 93 ± 2% (p = .005), respectively. There were no differences in re-intervention rates and renal function deterioration between the groups. The mean follow up time was 21 ± 14 months.

CONCLUSION

Incorporation of <4.0 mm RAs during F-BEVAR is associated with lower technical success, higher risk of arterial disruption and kidney loss, and lower patency rates at one year.

Anatomy and Physiology for the Abdominal Aortic Aneurysm Repair

In 2006, commercially produced endovascular aneurysm repair (EVAR) devices were approved by the Japanese Ministry of Health, Labour and Welfare, and their cost began to be covered by Japanese medical insurance. Meanwhile, the number of juxtarenal abdominal aortic aneurysms (AAA) to need the suprarenal clamp are increasing and the number of infra-renal AAAs are decreasing for open repair. In this era when EVAR has been growing rapidly for 11 years, it is a good opportunity to learn the surgical repair of AAA. I review the basic and advanced anatomy and physiology concepts which are needed for abdominal aortic repair, which are the proximal site (exposure of the proximal site, variation of renal arteries, variation of inferior vena cava and left renal vein, arcade of visceral branches of abdominal aorta, and coeliac plexus) and distal site (iliac artery, superior hypogastric plexus, ureter, inferior mesenteric artery, and lumbar arteries) separately. (This is a translation of Jpn J Vasc Surg 2019; 28: 173–177.)

Does the choice of intraoperative fluid modify abdominal aneurysm repair outcomes?: A cohort analysis

Intraoperatively administered hydroxyethyl starch could be a risk indicator for postoperative acute kidney injury (AKI) in vascular surgical patients.In a single-center retrospective cohort analysis, we assessed the impact of hydroxyethyl starch and other risk indicators on AKI and mortality in 1095 patients undergoing elective open abdominal aneurysm repair (AAA-OR) or endovascular aortic repair (EVAR). We established logistic regression models to determine the effect of various risk indicators, including hydroxyethyl starch, on AKI, as well as Cox proportional hazard models to assess the effect on mortality.The use of intravenous hydroxyethyl starch was not associated with an increased risk of AKI or mortality. Patients undergoing EVAR were less likely to develop AKI (4% vs 18%). Multivariate risk indicators associated for AKI included suprarenal or pararenal aortic cross-clamp [odds ratio (OR), 4.44; 95% confidence interval (95% CI), 2.538-7.784; P < .001] and procedure length (OR, 1.005; 95% CI, 1.003-1.007; P < .001), and favored EVAR (OR, 0.351; 95% CI, 0.118-0.654; P < .01). Main multivariate risk indicators associated with mortality included patients needing an urgent procedure [hazard ratio (HR), 2.294; 95% CI, 1.541-3.413; P < .001], those with suprarenal or pararenal aortic cross-clamp (HR, 1.756; 95% CI, 1.247-2.472; P < .01), and patients undergoing EVAR (HR, 1.654; 95% CI, 1.292-2.118; P < .001).We found neither a benefit nor a negative effect of hydroxyethyl starch on the risk of AKI or mortality. Instead, other variables and comorbidities were found to be relevant for the development of postoperative AKI and survival. Nevertheless, clinicians should be aware of the high risk of postoperative AKI, particularly among those undergoing AAA-OR procedures.

EVAR Approach for Abdominal Aortic Aneurysm with Horseshoe Kidney: A Multicenter Experience

BACKGROUND

Horseshoe kidney is a congenital abnormality, with an incidence of 0.25% of the total population. Only 0.12% of patients who undergo an abdominal aortic aneurysm repair might also have a coexisting horseshoe kidney. We present a series of 10 cases auspiciously treated with an endovascular approach along with their respective patient evolutions. A review of the literature is also presented.

MATERIALS AND METHODS

A retrospective review of the medical records (January 2004-December 2013) of 10 patients with abdominal aortic aneurysms and horseshoe kidney treated with endovascular repair was done. Patients were treated at 6 different centers in 3 different countries. Demographics, clinical status, medical history, anatomical morphology of the aneurysms and kidneys, as well as surgical outcomes were all analyzed.

RESULTS

The median age was 67.5 years (range 47-81), and the median aortic aneurysmal diameter was 57 mm (49-81 mm). A total of 35 arteries provided renal perfusion. There were 13 right renal arteries and 13 left renal arteries, all successfully preserved, with 9 isthmus arteries covered. Median hospital stay consisted of 3.5 days (1-14 days). All aortic aneurysms were successfully excluded with no endoleaks, hematomas, wound infections, or renal failure. During a median follow-up of 7 years, 3 patients died of myocardial infarction 7 years after endovascular aortic repair (EVAR), and the other 7 patients are doing well, with a median aneurysm reduction size sac of 16.5 mm.

CONCLUSIONS

Endovascular repair is a safe and efficient endovascular option for the treatment of patients presenting concomitant aortic aneurysm and horseshoe kidney, with excellent short- and medium-term outcomes. To our knowledge, our study represents the largest series of cases with horseshoe kidney successfully treated via EVAR without significant complications.

Abdominal aortic aneurysms: pre- and post-procedural imaging

Abdominal aortic aneurysm (AAA) is a relatively common, potentially life-threatening disorder. Rupture of AAA is potentially catastrophic with high mortality. Intervention for AAA is indicated when the aneurysm reaches 5.0-5.5 cm or more, when symptomatic, or when increasing in size > 10 mm/year. AAA can be accurately assessed by cross-sectional imaging including computed tomography angiography and magnetic resonance angiography. Current options for intervention in AAA patients include open surgery and endovascular aneurysm repair (EVAR), with EVAR becoming more prevalent over time. Cross-sectional imaging plays a crucial role in AAA surveillance, pre-procedural assessment, and post-EVAR management. This paper will discuss the current role of imaging in the assessment of AAA patients prior to intervention, in evaluation of procedural complications, and in long-term follow-up of EVAR patients.

Coverage of Accessory Renal Arteries During Endovascular Aortic Aneurysm Repair: What Are the Consequences and the Implications for Clinical Practice?

An accessory renal artery (ARA) represents an anatomic variation which can challenge endovascular aortic aneurysm repair (EVAR). The aim of this review was to summarize the current knowledge on postoperative outcomes following ARA coverage during EVAR. We performed a systematic literature review. The MEDLINE database was searched on September 2017, and 8 relevant studies were included. The frequency of ARA in patients undergoing EVAR varied between 9.5% and 16.2%, and the frequency of ARA coverage varied between 5.2% and 9.4%. Four reports did not observe any significant changes on postoperative renal function, whereas 1 study reported an early transient increase in creatinine after ARA coverage. The occurrence of renal infarct varied from 20% to 84%. Five studies did not observe endoleaks related to ARA coverage, whereas one reported the occurrence of type II endoleaks in 3 of 18 patients who had ARA coverage. No significant change in blood pressure, mortality, and mean length of hospital stay was observed. The ARA coverage can potentially have renal and vascular consequences, but none of them were critical. Further studies may be useful to identify preoperative criteria that may help to choose the most appropriate surgical approach before ARA coverage.

Prophylactic accessory renal artery coil embolization for prevention of type II endoleak following endovascular aneurysm repair: a case report

BACKGROUND

Prior reports indicate that intentional coverage of the accessory renal arteries (ARAs) with a diameter larger than 3 mm during endovascular aneurysm repair (EVAR) increases risk of additional treatment for type II endoleak. Here, we report a case of prophylactic coil embolization for a 4 mm ARA originating from an abdominal aortic aneurysm.

CASE PRESENTATION

A 76-year-old woman was admitted to our hospital after noticing an abdominal pulsatile mass. Computed tomography (CT) imaging revealed an abdominal aortic aneurysm (AAA) with a maximum diameter of 53 mm. Preoperative CT scan showed a right ARA, 4 mm in diameter, which was considered likely to lead to type II endoleak following EVAR. ARA coil embolization was performed at the time of EVAR. We observed no endoleaks and no infarct of the inferior pole of the right kidney on completion angiography. The postoperative course was uneventful, and the patient was discharged 7 days later. Postoperative eGFR (58.4 ml/min) was not significantly different from preoperative level (56.7 ml/min). After EVAR, blood pressure was under control, and no additional anti-hypertensive medicines were required. Postoperative enhanced CT image showed that the distal portion of the ARA was well perfused without type II endoleak from ARA.

CONCLUSIONS

Prophylactic coil embolization for a large ARA originating from an abdominal aortic aneurysm appears to be safe and effective in preventing type II endoleak following EVAR.

Abdominal Aortic Aneurysm With Ectopic Renal Artery Origins: A Case Report

The coexistense of an abdominal aortic aneurysm with ectopic main renal vasculature complicates aortic surgery and mandates a focused imaging evaluation and a carefully planned operation to minimize renal ischemia. We present the case of a 75-year-old man with an abdominal aortic aneurysm and a right kidney with two ectopic main renal arteries, one originating from the aneurysmal distal aorta and the other from the right common iliac artery; the patient underwent a surgical repair and followed an uneventful course with no deterioration of renal function. The preoperative and intraoperative details are reported, along with a review of the literature.

Renal Function is the Main Predictor of Acute Kidney Injury after Endovascular Abdominal Aortic Aneurysm Repair

BACKGROUND

Postoperative acute kidney injury (AKI) may occur in up to 18% of elective endovascular abdominal aortic aneurysm repair (EVAR) and has been associated with poor outcome; however, it is not clear which patients are at highest risk, to target renoprotection effectively. We sought to determine the predictive factors of AKI after elective EVAR.

METHODS

Overall, 947 patients undergoing elective EVAR between January 2004 and December 2014 were analyzed, using prospectively collected data. Postoperative AKI was defined by serum creatinine change within 48 hr, as per the Kidney Disease Improving Global Outcomes guidelines. Cardiovascular and kidney-disease risk factors were entered in univariate and multivariate analyses to assess influence on AKI development.

RESULTS

Overall, 167 (17.6%) patients developed AKI but only 2 patients required dialysis perioperatively. At multivariate analysis, adjusted for established AKI-risk factors and parameters that differed between groups at baseline, preoperative estimated glomerular filtration rate (eGFR; as per the chronic kidney disease epidemiology [CKD] formula); odds ratio (OR): 1.02 (per unit decrease); 95% confidence interval (CI): 1.003-1.041; P = 0.025; and chronic kidney disease (CKD) stage > 2 (OR: 1.28; 95% CI: 1.249-2.531, P = 0.001) were associated with development of AKI.

CONCLUSIONS

AKI was common after elective infrarenal EVAR and preoperative renal function appears to be the main factor associated with AKI. Patients with a low eGFR need to be targeted with more aggressive renal protection.

Long-Term Renal Function after Endovascular Aneurysm Repair

BACKGROUND AND OBJECTIVES

Endovascular repair (EVAR) is a common treatment for abdominal aortic aneurysm (AAA). However, its long-term effects on renal function remain unclear. We aimed to assess long-term renal dysfunction after EVAR using a contemporary estimate of GFR and to compare long-term renal outcomes in patients after EVAR with open aneurysm repair (OAR) and in patients without an AAA.

DESIGN, SETTINGS, PARTICIPANTS, & MEASUREMENTS

We performed a nested case-matched analysis of 726 patients (using a prospectively maintained database for repairs that took place between January 2000 and May 2010 in a tertiary center): 121 patients undergoing OAR (with data at baseline and 5 years postrepair) were case matched (age, sex, smoking, diabetes, baseline eGFR) to patients undergoing suprarenal and infrarenal fixation EVAR (242 in each group) and to 121 patients undergoing carotid endarterectomy (CEA) without AAA. Changes in eGFR were compared (1 and 5 years).

RESULTS

The OAR patients lost an average of 7.4 ml/min per 1.73 m2 at 5 years (95% confidence interval [95% CI], 4.8 to 10.6), compared with 8.2 ml/min per 1.73 m2 (95% CI, 6.5 to 10.8; P<0.001) for infrarenal-fixation EVAR, 16.9 ml/min per 1.73 m2 (95% CI, 13.0 to 21.9, P<0.001) for suprarenal-fixation EVAR, and 5.4 ml/min per 1.73 m2 (95% CI, 1.7 to 7.5; P<0.001) for CEA. The decrease in eGFR was steeper during the first postoperative year, with each group losing -2.2 ml/min per 1.73 m2 (infrarenal-fixation EVAR), -10.7 ml/min per 1.73 m2 (suprarenal-fixation EVAR), and -4.6 ml/min per 1.73 m2 (OAR), compared with -1.9 ml/min per 1.73 m2 for CEA.

CONCLUSIONS

Elective EVAR is associated with a significant decline in eGFR after 5 years, which is steeper in the first postoperative year and more pronounced compared with a similar population with atherosclerotic disease.

Incidence of Acute Kidney Injury (AKI) after Endovascular Abdominal Aortic Aneurysm Repair (EVAR) and Impact on Outcome

BACKGROUND

Acute kidney injury (AKI) is an important post-operative complication that may impact on mortality, morbidity, and cost. The incidence after endovascular aneurysm repair (EVAR) remains unknown, as the current literature has not employed consistent definitions. The aim of this study is to assess the incidence of AKI after elective EVAR and examine the impact of AKI on mortality and cardiovascular morbidity using the current universally accepted definitions.

METHODS

This was a cohort study using prospectively collected data, including consecutive patients undergoing elective EVAR for an infrarenal abdominal aortic aneurysm (AAA). Those with end stage renal failure were excluded. The primary endpoint was incidence of AKI as per the "Acute Kidney Injury Network" (AKIN), and "Kidney Disease Improving Global Outcomes" (KDIGO) criteria. Secondary endpoints included AKI stage, drop in estimated glomerular filtration rate (eGFR), and mortality and cardiovascular morbidity.

RESULTS

149 patients were included (16 females, 11%; mean age: 69 ± 8 years; mean AAA diameter: 6.0 ± 1.1 cm), 28 (18.8%) of whom developed AKI (26 patients classified as stage 1 and 2 as stage 2). Within 48 hours, those with AKI dropped their eGFR from 61 ± 20 mL/kg/1.73 m(2) to 51 ± 20 units (p < .001), and those without from 75 ± 9 to 74 ± 10 units (p < .001). None required dialysis during a 33 ± 11 month follow up. Development of AKI was associated with mortality (HR 0.035, 95% CI: 0.005 to 0.240, p < .001) and cardiovascular morbidity (HR: 0.021, 95% CI: 0.004 to 0.11, p < .001) on adjusted regression analysis.

CONCLUSIONS

The incidence of AKI after EVAR is significant and is independently associated with medium-term mortality and morbidity.

Preservation of the accessory renal arteries after endovascular repair of common iliac artery aneurysm using kissing stent grafts

Exclusion of the accessory renal arteries (ARAs) is required during endovascular aneurysm repair if they arise from the sealing zone or aneurysm sac. Here, we report a case of successful endovascular treatment for a common iliac artery aneurysm located close to the aortic bifurcation and associated with nephrotic syndrome in a 51-year-old man. The bilateral ARAs were successfully preserved using kissing stent grafts. During surgery, the proximal ends of endografts inserted from the bilateral femoral arteries were adjusted so that they met at the same level in the aorta, and simultaneous balloon dilatation was performed. This method can be a useful treatment option for common iliac aneurysms in cases with large ARAs.

Can an accessory renal artery be safely covered during endovascular aortic aneurysm repair?

A best evidence topic was constructed according to a structured protocol. The question addressed was whether coverage of an accessory renal artery (ARA) in patients undergoing endovascular aortic aneurysm repair (EVAR) is associated with increased risk of renal impairment. Altogether, 106 papers were located using the reported searches, of which 5 represented the best evidence to answer the question. The authors, journal, date and country of publication, study type, patient group studied, relevant outcomes parameters and results of these papers are tabulated. Our best evidence analysis included 116 patients who had one or more ARA excluded during EVAR. Segmental renal infarction occurred in varying numbers of patients (ranging from 0 to 84%). The authors consistently demonstrate that loss of renal mass is not associated with functional renal impairment, expressed by various outcome parameters such as serum creatinine, glomerular filtration rate (GFR), renal failure requiring dialysis and worsening hypertension. Comparisons of groups of patient with covered or preserved ARAs by one of the selected studies showed no difference in any of these renal outcome parameters, apart from a significantly higher renal infarct volume in the former group (P < 0.001). Subgroup analysis of patients with pre-existing renal dysfunction (GFR < 60 ml/h/m(2)) showed no difference in GFR change when comparing covered with uncovered ARA patient cohorts. No type II endoleak related to the covered ARA was reported in any of these studies. In conclusion, current evidence supports the safety of coverage of ARAs located in the proximal fixation zone to achieve seal in EVAR.

Oral contraceptive causing renal artery thrombosis

A young female presented with acute left lower quadrant pain followed by nausea and vomiting. She was found to have haematuria and elevated serum creatine. CT scan revealed a wedge-shaped hypodensity along with an intraluminal filling defect on the left kidney. Renal artery duplex showed no evidence for stenosis and MRI was negative for any atherosclerotic disease. Technetium scan confirmed the diagnosis of left renal infarct. Following day the patient became febrile and was noted to have leucocytosis and elevated serum lactate dehydrogenase. She was started on enoxaparin and low-dose aspirin. Blood cultures were negative. The oral contraceptive was stopped. Fever and leucocytosis resolved in the following 3 days. Extensive thrombophilic work-up was negative. No recurrence of thrombosis was found during a 6-month follow-up period. To the best of our knowledge, this is the first report of renal artery thrombosis leading to acute renal infarction associated with oral contraceptive use.

Predictors of creatinine rise post-endovascular abdominal aortic aneurysm repair

BACKGROUND

Endovascular abdominal aortic aneurysm repair involves manipulation of the aorta around the renal arteries. Fenestrated grafts involve the direct cannulation, stenting and injecting of contrast into the renal arteries. These procedures may be associated with an acute post-operative creatinine rise.

METHODS

We retrospectively examined data from all endovascular aortic repairs at our institution from 2005 to 2009, where contrast dosage had been recorded. Renal impairment was defined as a 25% increase in creatinine during the 5-day postoperative period. Univariable analysis was undertaken for a number of likely predictors, including: age, contrast dosage, preoperative creatinine, graft type (fenestrated or standard), diabetes mellitus, hypertension, hypercholesterolaemia, ischaemic heart disease, aspirin therapy, statins therapy, non-steroidal anti-inflammatory drug use, preoperative N-acetyl-cysteine and intravenous pre-hydration. Multivariable analysis was then applied to variables with a univariable P-value of < 0.05.

RESULTS

We identified 106 consecutive cases, with complete data for 102. Twenty per cent of patients developed renal impairment (22/102). Contrast dose (P = 0.043) and fenestrated grafts (P = 0.006) were identified as significant risk factors for post-operative creatinine increase (P = 0.043). Multivariable analysis demonstrated that fenestrated grafts were a risk factor independent of contrast dosage (P < 0.05).

CONCLUSIONS

Patients who received a fenestration graft (P < 0.01) and increased contrast dose (P < 0.05) were at a significant increased risk of a 25% post-operative creatinine rise. The risk of fenestration grafts persisted when multivariable regression was performed to control for contrast dosage (P < 0.05). Other variables investigated were not found to be significant in this study.

A unique case of a type II endoleak after EVAR caused by patent inferior mesenteric and accessory renal arteries

Type II endoleaks have been viewed as the Achilles' heel of endovascular repair of abdominal aortic aneurysms. This report describes a unique etiology to this common challenge and our approach to endovascular repair.

Multimodal approach to the endovascular treatment of embolisation or exclusion of the renal arteries and their distal and/or polar branches: personal experience

PURPOSE

This study reviews our experience over the last 10 years with procedures of embolisation and/or exclusion of the renal arteries, their parenchymal branches and the polar arteries [renal artery embolisation (RAE)].

MATERIALS AND METHODS

Twenty-seven patients (19 men and eight women; age range 37-93 years; mean 74 years) underwent RAE. The indications were: symptomatic gross haematuria in nine patients (33.3%) (tumour-related in seven and iatrogenic in two), symptomatic inoperable renal tumour in five (18.5%), large subcapsular or perirenal haematoma in three (11.1%) and aneurysm of the main renal artery in two (7.4%). Eight patients (29.6%) scheduled for endovascular aneurysm repair (EVAR) of the abdominal aorta underwent prophylactic embolisation of the renal polar branch arising from the aneurysmal sac or the subrenal aortic neck to prevent the possible revascularisation of the sac. Different embolisation agents were used: coils (17 cases), embolisation particles (14 cases), glue (one case), coated stent (two cases) and mechanical occlusion devices (two cases). In 11 cases, two to three different embolisation agents were used together.

RESULTS

Technical success was achieved in 26/27 patients (96.3%); in one case, embolisation of a polar artery arising from the aneurysmal sac was not possible. One case of gross haematuria recurred 13 months after the procedure and was re-treated with success. There were no cases of major or minor complications.

CONCLUSIONS

RAE is an effective and minimally invasive procedure in the treatment of neoplastic/iatrogenic symptomatic gross haematuria and in the palliative treatment of inoperable renal tumours. One possible new indication is the prophylactic exclusion of the polar artery arising from the neck or the sac of an abdominal aortic aneurysm in patients who are candidates for EVAR. In our experience, we observed very low morbidity and a short hospital stay. This procedure requires the availability of various materials for performing embolisation and experience in their use.