Suprarenal graft fixation in endovascular abdominal aortic aneurysm repair is associated with a decrease in renal function

The effect of suprarenal graft fixation during EVAR on short- and long-term renal function

OBJECTIVE

The effect of suprarenal fixation (SR) compared to infrarenal fixation (IR) on renal function during endovascular aneurysm repair (EVAR) remains controversial. This study aims to compare the renal outcomes between fixation types in short- and long-term follow-up.

METHODS

Patients undergoing EVAR for infrarenal abdominal aortic aneurysm between 2005 and 2013 were included. Estimated glomerular filtration rate (eGFR) was measured at baseline and during a follow-up of 5 years. A decline in renal function was defined as a ≥ 20% decrease in eGFR. Changes in eGFR were compared between SR and IR groups at 1-7 days, 30 days, and 1-5 years postoperatively. Preoperative renal insufficiency was defined as eGFR < 60mL/min/1.73m², and those patients were included in the subanalyses.

RESULTS

A total of 358 patients were included. Among these, 267 (74.6%) had SR and 91 (25.4%) had IR fixation. A decline in renal function occurred more commonly after SR than after IR in 1-7 days postoperatively (p = .009), but no difference was noticed at 30 days and 1-5 years. Regardless of the fixation method, renal function steadily decreased steadily over time after EVAR (estimate -3.13 per a year, 95% confidence interval -3.40- -2.85, p < .001). Patients with pre-existing renal insufficiency were included in subgroup analyses, and those with SR were more often found to have a decline in eGFR 5 years postoperatively than their counterparts with IR (59.5% vs 20.0%, p = .036).

CONCLUSION

An immediate postoperative decline in renal function was seen more often after SR fixation than IR fixation but this difference was transient. SR fixation is a safe method for patients with normal renal function. Long-term results seems to favor IR over SR in patients with pre-existing renal insufficiency.

Predictors of Decline in Renal Function 5 Years after EVAR

INTRODUCTION

While there exists copious short-term data regarding renal function following infra-renal endovascular abdominal aortic aneurysm repair (EVAR), long-term analysis is sparse. This is a single institution retrospective review of predictors of renal function decline 5 years after elective EVAR.

METHODS

All EVAR between 2007 and 2015 were queried. Patients in whom renal function was documented 5 years postoperatively were included in analysis. Exclusion criteria were ruptured aneurysm, mortality before 56 months, lack of follow-up, ESRD status, and concomitant renal intervention. The primary outcome investigated was a 20% or greater drop in glomerular filtration rate (GFR) 5 years postoperatively. The following variables at the time of surgery were investigated as potential predictors: age, gender, hypertension, hyperlipidemia, diabetes, CAD or prior MI, COPD, prior stroke, baseline eGFR under 60 mL/min/1.73 m², supra-renal fixation, infra-renal fixation, neck diameter, neck length, and number of contrast CT.

RESULTS

354 EVAR were identified of which 143 met inclusion criteria (211 excluded). Univariate analysis revealed female gender (OR 2.7), hypertension (OR 9.4), baseline renal insufficiency (OR 3.8), larger neck diameter, and supra-renal fixation (OR 2.32) all predictive (P < .05) of GFR drop at 5 years. Multivariate binary logistic regression analysis found female gender (multivariate OR 3.9, P = .023) and baseline renal insufficiency (multivariate OR 3.0, P = .029) as significant predictors of greater than 20% GFR drop at 5 years. Only 2 patients of the 143 progressed to dialysis requirement at 5 years.

CONCLUSIONS

Females and patients with baseline renal insufficiency are more vulnerable to significant decline in renal function 5 years following EVAR. Consistent with analogous literature, supra-renal fixation appears moderately deleterious toward renal function with no clinical significance in those with baseline normal renal function. The potential benefit of avoidance of supra-renal fixation in female patients with baseline renal insufficiency is worth further investigation in a more robust multi-center study.

Effect of stent graft fixation types on pararenal aortic diameter and renal function after endovascular aortic repair

Background: This study aims to identify pararenal aortic diameter changes following endovascular aortic repair and to investigate the effects of suprarenal fixation on renal function.

Methods: Between May 2006 and January 2019, a total of 168 patients (135 males, 33 females; mean age: 75.2±8.4 years; range, 48 to 93 years) who underwent endovascular aortic repair were retrospectively analyzed. To compare the effects of graft types, we measured the change in pararenal aortic diameter at four levels: below the celiac artery, below the superior mesenteric artery, at the lowest renal artery, and 1 cm below the lowest renal artery. To evaluate the effect of suprarenal fixation on renal function, serial measurements of serum creatinine, glomerular filtration rate, creatinine clearance rate, and estimated glomerular filtration rate were made. We examined the factors related to post-procedural aortic diameter.

Results: The mean change in the aortic diameter was statistically significant, being 12.9±10% in the suprarenal fixation group and 6.19±6.9% in the infrarenal fixation group only at the lowest renal artery level (p=0.001). There was no significant difference in the rate of type I endoleak (p=0.330) or renal function and adverse events (p>0.107) between the groups. The formula for calculating post-procedural aortic diameter was as follows: post-procedural aortic diameter (renal artery level, mm) =1.845 (in case of suprarenal fixation) + 1.012 × pre-procedural aortic diameter (renal artery level, mm) + 0.029 × follow-up time (months) + 0.039 × oversizing (%) (R2=0.773, p<0.001).

Conclusion: Suprarenal fixation affects the infrarenal aortic diameter at the lowest renal artery level without significant type I endoleak. However, it does not result in significant renal dysfunction. Pre-procedural aortic diameter, computed tomography follow-up time, suprarenal fixation type, and stent oversizing are the only definite independent correlation factors for postprocedural aortic diameter. This formula can predict the change of aortic diameter after endovascular aortic repair.

Diseases of the Aorta and Kidney Disease: Conclusions from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference

Chronic kidney disease (CKD) is an independent risk factor for the development of abdominal aortic aneurysm (AAA), as well as for cardiovascular and renal events and all-cause mortality following surgery for AAA or thoracic aortic dissection. In addition, the incidence of acute kidney injury (AKI) after any aortic surgery is particularly high, and this AKI per se is independently associated with future cardiovascular events and mortality. On the other hand, both development of AKI after surgery and the long-term evolution of kidney function differ significantly depending on the type of AAA intervention (open surgery vs. the various subtypes of endovascular repair). Current knowledge regarding AAA in the general population may not be always applicable to CKD patients, as they have a high prevalence of co-morbid conditions and an elevated risk for periprocedural complications. This summary of a Kidney Disease: Improving Global Outcomes Controversies Conference group discussion reviews the epidemiology, pathophysiology, diagnosis, and treatment of Diseases of the Aorta in CKD and identifies knowledge gaps, areas of controversy, and priorities for future research.

Central and peripheral arterial diseases in chronic kidney disease: conclusions from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference

Chronic kidney disease (CKD) affects about 10% of all populations worldwide, with about 2 million people requiring dialysis. Although patients with CKD are at high risk of cardiovascular disease and events, they are often underrepresented or excluded in clinical trials, leading to important knowledge gaps about how to treat these patients. KDIGO (Kidney Disease: Improving Global Outcomes) convened the fourth clinical Controversies Conference on the heart, kidney and vasculature in Dublin, Ireland, in February 2020, entitled Central and Peripheral Arterial Diseases in Chronic Kidney Disease. A global panel of multidisciplinary experts from the fields of nephrology, cardiology, neurology, surgery, radiology, vascular biology, epidemiology, and health economics attended. The objective was to identify key issues related to the optimal detection, management, and treatment of cerebrovascular diseases, central aortic disease, renovascular disease, and peripheral artery disease in the setting of CKD. This report outlines the common pathophysiology of these vascular processes in the setting of CKD, describes best practices for their diagnosis and management, summarizes areas of uncertainty, addresses ongoing controversial issues, and proposes a research agenda to address key gaps in knowledge that, when addressed, could improve patient care and outcomes.

Early Postoperative Renal Dysfunction Predicts Long-Term Renal Function Degradation after Type IV Thoracoabdominal Aortic Aneurysm Surgical Repair

BACKGROUND

Type IV thoracoabdominal aortic aneurysm surgical repair is often complicated by postoperative acute kidney injury. The aim was to evaluate early renal injury influence on long-term renal function.

METHODS

All type IV thoracoabdominal surgical repair performed between January 2000 and January 2014 in our tertiary hospital were included in this retrospective observational study. All procedures were performed through a retroperitoneal approach with at least suprarenal aortic cross-clamping. Cold Ringer Lactate was used to perfuse the kidneys. Serum creatinine (Scr.) and glomerular filtration rate (GFR) were recorded preoperatively, daily until discharge and at least annually during follow-up. Postoperative renal dysfunction was classified using the RIFLE score. Predictors of long-term renal decline were identified by logistic regression and a Cox model.

RESULTS

Of total, 80 patients were included. Aortic clamping level was suprarenal (10%), supramesenteric (37%) or supracoeliac (53%). Ischemic durations were 29 ± 9 min for the gastrointestinal tract and the right kidney, 54 ± 28 min for the left kidney. Three patients died postoperatively. At discharge, 31 (38.8%) patients did not have a postoperative renal impairment (RIFLE-), compared with 49 (61.2%) who had a renal dysfunction (RIFLE+). GFR was 89 ± 29 ml/min vs 68 ± 37 ml/min, respectively (P < 0.01). In the RIFLE + group, Scr. was increased by x1.5 (Risk) for 22 patients, x2 (Injury) for 19 patients, and ×3 (Failure) for 8 patients. Mean follow-up was 59 months. Eighteen patients died, and 2 patients started permanent dialysis at 46 and 118 months during follow-up. The only predictive factor of long-term GFR degradation was a postoperative GFR below 45 ml/min (OR: 16.5; 95%; P < 0.001).

CONCLUSIONS

Postoperative renal dysfunction was a frequent complication, associated with long-term renal function degradation.

Analysis of host Toll-like receptor 3 and RIG-I-like receptor gene expression in patients with abdominal aortic aneurysm

OBJECTIVE

Abdominal aortic aneurysm (AAA) is a vascular disease relatively common in the elderly population. Although some events that contribute to the development and progression of AAA are known, there are limited data examining the association of Toll-like receptor 3 (TLR3) and RIG-I-like receptor expression with the pathogenesis of AAAs. In this study, we investigated the gene and protein expression of TLR3 and RIG-I-like receptors (RIG-I and MDA5) in aortic wall and blood of AAA patients and examined the relationship between their expression and immune response.

METHODS

Total RNA was extracted from aortic wall tissues and blood samples collected from 20 patients with AAA and blood samples of 17 healthy volunteers without aortic aneurysm. To evaluate the DDX58 (RIG-I), IFIH1 (MDA5), and TLR3 gene expression level, quantitative real-time polymerase chain reaction was used. Extracellular cytokine and pattern recognition receptor levels were quantified by enzyme-linked immunosorbent assays.

RESULTS

TLR3, RIG-I, and MDA5 were constitutively expressed in both aortic tissues and blood samples from AAA patients and healthy volunteers. In patients with AAA, higher TLR3 expression in aortic tissues than in blood was found (P = .004). The DDX58 messenger RNA expression was higher in blood of patients with AAA compared with healthy subjects (P = .021). A significantly higher level of plasma interleukin 4 was noticed in patients with AAA than in healthy individuals (P = .008).

CONCLUSIONS

This study suggests that RIG-I and TLR3 seem to be important factors in the pathogenesis of AAA.

Occurrences and Results of Acute Kidney Injury after Endovascular Aortic Abdominal Repair?

Purpose

Acute kidney injury (AKI) is an important postoperative complication that may impact mortality and morbidity. The incidence of AKI after elective endovascular aneurysm repair (EVAR) is not known well. The aim of this study is to assess the incidence of AKI after elective EVAR and examine the impact of AKI.

Materials and Methods

Data were collected and analyzed retrospectively from 78 elective EVARs for abdominal aortic aneurysm (AAA) among 102 total cases of conventional EVAR performed in Inha University Hospital from 2009 to 2015. The primary endpoint was incidence and risk factors of AKI. Secondary endpoints included drop in estimated glomerular filtration rate (eGFR) and the mortality of AKI.

Results

We included 78 patients (17 females, 21%; mean age, 73.9±12.5 years; mean AAA diameter, 59.3±8.9 cm), 11 (14.1%) of whom developed AKI. Within 48 hours, those with AKI experienced a decrease in eGFR from 65.5±21.2 to 51.2±19.6 mL/kg/1.73 m², and those without AKI showed a change from 73.1±9.2 to 74.2±10.7 mL/kg/1.73 m². There were no patients who required dialysis during follow-up (mean, 24.2±18.0 months). Development of AKI was related to operation time (odds ratio [OR], 2.024; 95% confidence interval [CI], 1.732–4.723; P<0.010) and contrast dose (OR, 3.192; 95% CI, 2.182–4.329; P<0.010). There were no differences in mortality between the 2 groups (P=0.784).

Conclusion

The incidence of AKI after EVAR was related to operation time and contrast dose, but was not associated with medium-term mortality.

Determinants of Acute Kidney Injury and Renal Function Decline After Endovascular Abdominal Aortic Aneurysm Repair

OBJECTIVE/BACKGROUND

Endovascular aneurysm repair (EVAR) may be associated with renal injury and more insight is needed into potential risk factors. The aim was to identify clinical, anatomical, and peri-procedural parameters as potential risk factors for the occurrence of acute kidney injury (AKI) and to evaluate chronic kidney disease (CKD) after EVAR.

METHODS

A cohort of 212 consecutive patients who underwent elective EVAR for abdominal aortic aneurysm from January 2009 to October 2016 was included. A subgroup of 149 patients with 2 years follow-up was compared with a set of 135 non-operated aneurysm patients with smaller aneurysms (similar cardiovascular risk profile) to assess CKD. Primary outcomes were AKI (Acute Kidney Injury Network criteria) and CKD measured by estimated glomerular filtration rate (Kidney Disease Improving Global Outcomes guidelines). For AKI, candidate risk factors were identified by univariate and multivariate logistic regression analysis; for chronic renal function decline, risk factors were identified using Cox regression analysis.

RESULTS

AKI occurred in 30 patients (15%). On multivariate analysis, the use of angiotensin II blocker (odds ratio [OR] 4.08, 95% confidence interval [CI] 1.38-12.07) and peri-operative complications (OR 3.12, 95% CI 1.20-8.10) were independent risk factors for AKI, whereas statin use was a protective factor (OR 0.19, 95% CI 0.07-0.52). EVAR resulted in a significant increase (23.5%) in the occurrence of CKD compared with the control group (6.7%; p <.001). On univariate and multivariate Cox regression the risk factors: aortic neck diameter (per mm increase) (hazard ratio [HR] 1.13, 95% CI 1.02-1.25), renal artery stenosis >50% (HR 2.24, 95% CI 1.05-4.79), and the occurrence of AKI (HR 2.19, 95% CI 0.99-4.85) were significant predictors of CKD.

CONCLUSION

This study identified use of angiotensin II blockers and peri-operative complications as risk factors for AKI. In addition, the problem of renal function decline after EVAR is highlighted, which indicates that prolonged protective measures (e.g., in those patients at high risk) over time are needed to improve patient outcomes.

Current aortic endografts for the treatment of abdominal aortic aneurysms

Endovascular Aneurysm Repair is a widely adopted method of treatment for patients with abdominal aortic aneurysms. The minimally invasive approach offered with EVAR has become popular not only among physicians and patients, but in the medical device industry as well. Over the past 25 years the global market for aortic endografts has increased rapidly, resulting in a wide range of devices from various companies. Currently, there are seven endografts approved by the FDA for the treatment of abdominal aortic aneurysms. These devices offer a wide range of designs intended to increase inclusion criteria while decreasing technical complications such as endoleak and migration. Despite advances in device design, secondary interventions and follow-up requirements remain a significant issue. New devices are currently being studied in the U.S. and abroad and may significantly reduce complications and secondary interventions.

Risk factors for early renal dysfunction following endovascular aortic aneurysm repair and its effect on the postoperative outcome

PURPOSE

Renal insufficiency is associated with increased morbidity and death after endovascular aortic aneurysm repair (EVAR). However, the effect of postoperative acute kidney dysfunction on patient outcome has not been fully determined. This study aimed to determine the risk factors of early postoperative renal function decline using chronic kidney disease (CKD) staging and its effect on the clinical outcome.

METHODS

A retrospective analysis was performed on a prospectively maintained EVAR database. Pre- and postoperative CKD stages were determined for all patients according to the estimated glomerular filtration rate values.

RESULTS

We identified 135 patients who were treated with elective EVAR. CKD stage decline was observed in 25 (19 %) of the patients. Freedom from aneurysm-related death was significantly lower in patients with postoperative CKD progression compared with those with unchanged CKD stage. A shaggy aorta without oral beta-blocker administration and higher preoperative serum creatinine levels (>1.4 mg/dL) were found to be independent predictors of an early postoperative CKD stage decline.

CONCLUSIONS

Patients with postoperative CKD progression have an increased frequency of aneurysm-related death. The presence of a shaggy aorta, absence of oral beta-blocker administration and an increased preoperative creatinine level are independent predictors of early postoperative CKD progression.

Quantified Aortic Luminal Irregularity as a Predictor of Complications and Prognosis After Endovascular Aneurysm Repair

Atheromatous degeneration of the aorta is considered to be a risk factor for postoperative embolic complications after endovascular treatment, and is associated with a high incidence of vascular events in the long term. We devised a method to quantify the shagginess of the aorta using contrast-enhanced computed tomography (CT) images. This study examined the method's validity and prognostic usefulness in patients undergoing elective endovascular abdominal aortic aneurysm repair (EVAR). We retrospectively investigated 427 patients who underwent elective EVAR between 2007 and 2013. Preoperative contrast-enhanced CT images with a slice thickness of 1 mm were analyzed using a workstation, and the degree of aortic luminal irregularity from the level of the left subclavian artery ostium to that of the celiac artery ostium was quantified by computing a shagginess score. We compared the computed scores with subjective visual assessments of aortic shagginess. Subsequently, we evaluated the relationship between the computed scores and postoperative prognosis. The shagginess scores were significantly correlated with the visual assessments of the aortic lumen, which were performed by 5 experienced vascular surgeons (rho ranged from 0.564-0.654, all P < 0.001). Multiple logistic regression analysis demonstrated that the shagginess score was independently associated with the development of renal impairment within a month after EVAR (odds ratio, 2.78; 95% confidence interval [CI], 1.83-4.22, P < 0.001). The shagginess score was significantly higher in patients who suffered postoperative intestinal and peripheral ischemic complications, as compared with those who did not (P < 0.001). The mean postoperative follow-up period was 1207 ± 641 days. Cox proportional hazards regression showed that the shagginess score was a significant independent predictor of all-cause and cardiovascular mortality (hazard ratio [HR], 1.37; 95% CI, 1.09-1.72, P = 0.007, and HR, 1.51; 95% CI, 1.04-2.18, P = 0.030, respectively). The results suggest that the shagginess score provides a quantitative reflection of aortic luminal irregularity. It may serve as a useful predictive factor for postoperative renal function deterioration, embolic complications, and long-term mortality after elective EVAR.

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.

Impact of Fenestrated Endovascular Abdominal Aortic Aneurysm Repair on Renal Function

Purpose: To investigate the impact of fenestrated endovascular aneurysm repair (fEVAR) on renal function perioperatively and at midterm. Methods: A case-controlled study was performed involving 58 patients (mean age 75±7 years; 51 men) who underwent elective fEVAR for a juxtarenal or short-necked abdominal aortic aneurysm (AAA) matched on age, sex, smoking, diabetes, and baseline estimated glomerular filtration rate (eGFR) with a contemporaneous group undergoing open aneurysm repair (OAR) for the same indications. Perioperative incidence of acute kidney injury (AKI) and levels of eGFR at 30 days and 1 year were compared. A systematic literature review was performed to identify studies that had used eGFR as renal outcome after fEVAR; the pooled data were meta-analyzed using an eGFR drop >30% at 1 month and the latest follow-up as endpoints. Results are reported as the pooled proportion and 95% confidence interval (CI). Results: The incidence of AKI after fEVAR was 28% compared to 10% after OAR (p=0.03). Following fEVAR, the mean eGFR dropped from 78±8 to 74±9 mL/min/1.73 m2 at 30 days compared to a change from 79±8 to 80±16 mL/min/1.73 m2 after OAR (p<0.01). However, the absolute drop in eGFR between fEVAR and OAR at 1 year was similar (7 mL/min/1.73 m2; p=0.53); 7% of the fEVAR patients had an eGFR drop >30% at that point compared with none for OAR (p=0.12). The systematic literature review identified eGFR outcomes for 193 fEVAR patients. Combining these patients with the 58 from our cohort study, the pooled proportions of eGFR drop >30% were 20% (95% CI 9% to 39%) at 30 days and 8% (95% CI 0.5% to 13%) at the end of follow-up. Conclusion: fEVAR has a significant perioperative impact on renal function, but 1-year results are similar to OAR. fEVAR patients may benefit from targeted AKI prevention strategies that need to be assessed in relevant studies.

The association of simple renal cysts with abdominal aortic aneurysms and their impact on renal function after endovascular aneurysm repair

We validated the association of simple renal cysts with abdominal aortic aneurysm and other cardiovascular factors and assessed simple renal cysts’ impact on renal function before and after endovascular abdominal aortic aneurysm repair. A retrospective analysis of prospectively collected data was conducted. Computed tomography angiograms of 100 consecutive male patients with abdominal aortic aneurysm who underwent endovascular abdominal aortic aneurysm repair (Group 1) were reviewed and compared with 100 computed tomography angiogram of aged-matched male patients without abdominal aortic aneurysm (Group 2). Patients’ demographic data, risk factors, abdominal aortic aneurysm diameter, the presence of simple renal cyst and laboratory tests were recorded. No difference was observed between the two groups in respect to other cardiovascular risk factors except hyperlipidemia with higher prevalence in Group 1 ( p < 0.05). Presence of simple renal cysts was independently associated with age ( p < 0.05) and abdominal aortic aneurysm ( p = 0.0157). There was no correlation between simple renal cysts and abdominal aortic aneurysm size or pre-operative creatinine and urea levels. No difference was observed in post-operative creatinine and urea levels either immediately after endovascular abdominal aortic aneurysm repair or in 12-month follow-up. In male patients, the presence of simple renal cysts is associated with abdominal aortic aneurysm and is increasing with age. However, their presence is neither associated with impaired renal function pre-endovascular abdominal aortic aneurysm repair and post-endovascular abdominal aortic aneurysm repair nor after 12-month follow-up.

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.

A systematic review and meta-analysis indicates underreporting of renal dysfunction following endovascular aneurysm repair

Deterioration in renal function has been described after endovascular repair of abdominal aortic aneurysms (EVRs). The etiology is multifactorial and represents an important therapeutic target. A need exists to quantitatively summarize incidence and severity of renal dysfunction after EVR to allow better-informed attempts to preserve renal function and improve life expectancy. Here a systematic search was performed using Medline and Embase for renal function after EVR applying PRISMA statements. Univariate and multivariate random-effects meta-analyses were performed to estimate pooled postoperative changes in serum creatinine and creatinine clearance at four time points after EVR. Clinically relevant deterioration in renal function was also estimated at 1 year or more after EVR. Pooled probability of clinically relevant deterioration in renal function at 1 year or more was 18% (95% confidence interval of 14-23%, I2 of 82.5%). Serum creatinine increased after EVR by 0.05 mg/dl at 30 days/1 month, 0.09 mg/dl at 1 month to 1 year, and 0.11 mg/dl at 1 year or more (all significant). Creatinine clearance decreased after EVR by 5.65 ml/min at 1 month-1 year and by 6.58 ml/min at 1 year or more (both significant). Thus, renal dysfunction after EVR is common and merits attention.

Postoperative "Chimney" for Unintentional Renal Artery Occlusion after EVAR

Renal artery obstruction during endovascular repair of abdominal aortic aneurysm using standard device is a rare but life-threatening complication and should be recognized and repaired rapidly in order to maintain renal function. Both conventional surgery and endovascular stenting have been reported. We report a case of late postoperative bilateral “chimney” to resolve a bilateral thrombosis of the renal artery following an uncomplicated endovascular aortic repair.

Thromboembolic complications after endovascular repair of abdominal aortic aneurysm with neck thrombus

OBJECTIVE

To evaluate outcomes after endovascular aneurysm repair (EVAR) for abdominal aortic aneurysm (AAA) with neck thrombus.

METHODS

We retrospectively reviewed patients who underwent EVAR for AAA at our institution from 2007 to 2011. Patients with ruptured AAA, chronic renal failure, or hostile neck characteristics other than thrombus were excluded. Patients were divided into 2 groups: group T (with neck thrombus) and group N (without neck thrombus). We compared complications and mid-term outcomes.

RESULTS

There were no differences in success rates between the groups, but there were higher rates of thromboembolic complications such as distal embolization (20% vs 0%, P = .02) and renal dysfunction (36.8% vs 11.1%, P = .03) in group T than in group N. Suprarenal thrombus and suprarenal fixation in the presence of suprarenal thrombus were associated with postoperative renal dysfunction (P = .01).

CONCLUSION

The EVAR for AAA with neck thrombus is associated with thromboembolic complications.