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

A Pilot Study of Endovascular Repair for Ruptured Aortic Aneurysms With the Use of Carbon Dioxide Angiography Alone

INTRODUCTION

Endovascular aortic repair (EVAR) of a ruptured abdominal aortic aneurysm (rAAA) has become a common approach. Hemorrhagic shock associated with the use of iodinated contrast medium (ICM) increases the risk of acute kidney injury (AKI). Theoretically, eliminating ICM from EVAR can decrease that risk. The aim of this pilot study was to analyze the feasibility and safety of emergent EVAR performed with the exclusive use of carbon dioxide (CO2) for a rAAA.

METHODS

Since 2021, all consecutive rAAAs with hemorrhagic shock and suitable anatomical criteria for a standard endograft have been treated by EVAR with the exclusive use of CO2 using an automated CO2 injector (Angiodroid SpA, San Lazzaro di Savena, Italy).

RESULTS

Eight percutaneous EVARs were performed under local anesthesia. Median age was 78 (interquartile range [IQR]=6) years, 5 patients were male. The technical success was 100%, the 30-day mortality was 25% (n=2), the median amount of administered CO2 was 400 (IQR=60) ml. The median change in serum creatinine level between admission, post-operative and 30-day values was an increase of 0.14 mg/dL and a decrease of 0.11 mg/dL, respectively. Post-operative AKI occurred in the two patients who died. All 6 surviving patients showed sac shrinkage >5 mm, and no reinterventions at a median follow-up of 10 months.

CONCLUSIONS

Endovascular repair of rAAA with the exclusive use of CO2 as contrast agent is technically feasible and safe. Further studies are needed to determine whether CO2 increases survival rate and limits the progression of renal dysfunction after endovascular repair of rAAA.Clinical ImpactThe recorded rate of post-operative AKI after endovascular repair of rAAA performed with the use of CO2 found in this pilot study was significantly lower than the one reported in the literature with the use of ICM. Our hyphotesis is that the use of CO2 during rEVAR might increase survival rate and limits the progression of renal dysfunction.

Editor's Choice - Feasibility and Safety of Using Carbon Dioxide Exclusively in Regular Endovascular Aortic Aneurysm Repair: Results of a Multicentre, Prospective, Zero Iodine Contrast Endovascular Aneurysm Repair Study

OBJECTIVE

Carbon dioxide (CO2) angiography has emerged as a viable alternative to regular iodinated contrast medium (ICM) for guiding endovascular aneurysm repair (EVAR) procedures. This study aimed to evaluate the feasibility and safety of a standardised EVAR procedure using only CO2 angiography.

METHODS

A prospective, multicentre, national study enrolled consecutive patients between January 2023 and January 2024 with asymptomatic abdominal aortic aneurysms measuring ≥ 55 mm and for whom a standard endovascular graft (instructions for use) was anatomically feasible. The study involved the use of an automatic CO2 injector to standardise intra-operative imaging. A strategy comprising five standardised steps was devised to visualise a target vessel (TV) that could not be seen during the first CO2 angiogram. The five steps were: (A) place the introducer closer to the TV; (B) tilt the table by 5 - 10° in the direction opposite to the TV; (C) selectively cannulate the TV; (D) cannulate the contralateral gate (only for repositionable devices); CO2 angiography was repeated in steps 1 - 2; and (E) use ICM.

RESULTS

Two hundred and ninety-three patients were enrolled (10 centres), with a median age of 78 (interquartile range [IQR] 72, 83) years; 256 (87.4%) were male. The overall procedure time, fluoroscopy time, and injected CO2 volume were 90 (IQR 65, 125) minutes, 15 (IQR 10, 22) minutes, and 600 (IQR 400, 800) mL, respectively. The 30 day mortality, complication, and re-intervention rates were 0.3% (n = 1), 6.8% (n = 20), and 2.4% (n = 7), respectively. CO2 related adverse events were rare (1%; n = 3) and minor. A zero iodine contrast EVAR procedure was feasible in 240 (patients 81.9%). The five standardised steps were used extensively: step A, 170 procedures (58.0%); step B, 109 procedures (37.2%); step C, 21 procedures (7.2%); step D, 14 procedures (4.8%); and step E, 53 procedures (18.1%), with a median volume of 20 (IQR 10, 35) mL. Significant predictors for ICM use were aneurysm diameter > 70 mm and a lowermost renal artery positioned between 3 and 9 o'clock.

CONCLUSION

This study demonstrated that the standardised zero iodine contrast EVAR protocol reported here is both safe and feasible and is applicable in 82% of consecutive non-selected patients. Limitations primarily arose from anatomical factors, and adjunctive standardised manoeuvres can effectively address these challenges in most cases.

Results of the Italian Collaborators for Evar Registry on Acute Kidney Injury After Elective Endovascular Aortic Repair of Infrarenal Abdominal Aortic Aneurysm

OBJECTIVES

To analyze the incidence and predictive factors of postoperative acute kidney injury (AKI) after elective standard endovascular aortic repair (EVAR) in a large recent, multicenter cohort.

MATERIALS AND METHODS

This is a multicenter, retrospective, financially unsupported physician-initiated observational cohort study. Between January 2018 and March 2021, only patients treated with elective standard EVAR for infrarenal non-infected abdominal aortic aneurysm were analyzed. Patients already on hemodialysis (HD) were excluded. AKI was defined as an increase in serum creatinine (sCr) ≥0.3 mg/dL within 48 hours or an increase in sCr to ≥1.5 times baseline known or presumed to have occurred within 7 days, or a urine volume of <0.5 mL/kg/h for 6 hours. Primary outcomes of interest were AKI incidence at 30 days and freedom from HD at 1-year follow-up. Secondary outcomes were freedom from severe postoperative complication, and freedom from aorta-related mortality (ARM) at 1 year.

RESULTS

The final cohort analyzed 526 (29.8%). There were 489 (93%) males and 37 (7%) females: the median age was 76 years (interquartile range [IQR], 71-81). Chronic kidney disease (CKD) was present in 86 (16.3%) patients. Early mortality was observed in 8 (1.5%) patients, none was aorta-related. Complication rate was 17.1% (n=89). AKI was observed in 17 (3.2%). Renal replacement therapy was needed in 4 (0.8%). HD was transitory in 2 cases and definitive in 1. Binary logistic regression analysis identified CKD (odds ratio [OR]: 4.68, 95% confidence interval [CI]: 2.10-10.45, p<0.001), and the presence of renal artery stenosis (OR: 3.80, 95% CI: 1.35-10.66, p=0.011) to be associated with an increased risk of postoperative AKI. Estimated freedom from ARM was 94.9% at 1 year. Estimated freedom from HD rate at 1 year was 94%: This was significantly different between patients with preoperative CKD and those who did not have preoperative CKD (log-rank, p=0.042).

CONCLUSION

AKI after elective standard EVAR still occurs but with an acceptably low incidence rate. Preoperative CKD is the most important predictor for postoperative AKI, which was not associated with the need for HD at 1-year follow-up but with a higher propensity of mortality.

CLINICAL IMPACT

This "real world" experience confirm that EVAR performed with standard contrats agent protocol remains safe for acute kidney injury development. Therefore, only patients presenting with preoperative borderline or ascertained chronic kidney disease will take the most advantage from the use of carbon dioxide contrast.

Risk Factors for Acute Renal Failure After Endovascular Aneurysm Repair

BACKGROUND

Acute kidney injury (AKI) after endovascular aortic aneurysm repair (EVAR) is uncommon though carries significant morbidity. Procedural risk factors are not well established for acute renal failure (ARF) that requires initiation of dialysis. The goal of this study was to examine the impact of ARF on patients undergoing EVAR and identify risk factors for ARF using a large, national dataset.

METHODS

Patients undergoing EVAR were identified from the National Surgical Quality Improvement Program (NSQIP) database over 9 years, ending in 2019. Demographics, indication for repair, comorbidities, procedural details, complications, hospital and ICU LOS, and mortality were recorded. Patients were stratified by presence of ARF and compared. Patients were further stratified by indication for EVAR and presence of ARF. Multivariable logistic regression (MLR) analysis was performed to determine the independent predictors of ARF.

RESULTS

18 347 patients were identified. Of these 234 (1.3%) developed ARF requiring dialysis. Mortality (40 vs 1.8%, P < .0001), ICU LOS (5 vs 0 days, P < .0001), and hospital LOS (11 vs 2 days, P < .0001) were all significantly increased in patients with ARF. Multivariable logistic regression identified increasing diameter, creatinine, operative time, preoperative transfusions, ASA class, emergent repair, female gender, and juxtarenal/suprarenal proximal landing zone as predictors of ARF.

CONCLUSIONS

ARF after EVAR causes significant morbidity, prolongs hospitalizations, and increases mortality rates. Those patients at risk of ARF after EVAR should be closely monitored to reduce both morbidity and mortality.

Predictors of Five-Year Survival after EVAR: 10-Year Experience of Single-Center Cohort Study

BACKGROUND

Endovascular abdominal aortic repair (EVAR) is the main therapeutic option for repairing abdominal aortic aneurysms (AAAs). We aimed to determine the long-term outcomes of patients who underwent EVAR at our center.

METHODS

In this retrospective cohort study, patients who underwent EVAR for intact isolated AAA at Tehran Heart Center between 2007 and 2017 were included. Clinical outcomes and the frequency of mortality were analyzed for follow-up periods. We calculated the 5-year survival rate and its predictors for our patients using Kaplan-Meier estimation.

RESULTS

We included the data of all patients (154 patients, mean age = 70.7 [± 8.0] years, 96.1% men) who successfully underwent EVAR at our center. The most common risk factors were coronary artery disease (70.1%), hypertension (68.2%), smoking (64.9%), and dyslipidemia (39.6%). There was no mortality during the procedure. The median follow-up was 65.5 months. An average decrease of 9.07 mm (95% confidence interval: 6.9-11.2) occurred in the size of the AAA. During follow-up, 12 patients developed some complications, 49 died, and 7 did not complete the follow-up. The 5-year survival rate was 75% (3.9%). The independent predictors for 5-year survival were age (hazard ratio [HR] = 1.06, P = 0.002) and anemia (HR = 1.91, P = 0.029). Despite not being statistically significant, dyslipidemia (HR = 0.573, P = 0.078) and long intensive care unit/cardiac care unit stays (HR = 1.08, P = 0.070) were borderline mortality predictors.

CONCLUSIONS

This study depicted an acceptable survival rate for patients who underwent EVAR at our center. Age and anemia, 2 modifiable predictors of 5-year survival, can probably prolong the survival rate of patients, which requires evaluation later.

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.

A novel pre-operative risk assessment tool to identify patients at risk of contrast associated acute kidney injury after endovascular abdominal aortic aneurysm repair

OBJECTIVES

Contrast-associated acute kidney injury (CA-AKI) after endovascular abdominal aortic aneurysm repair (EVAR) is associated with mortality and morbidity. Risk stratification remains a vital component of preoperative evaluation. We sought to generate and validate a pre-procedure CA-AKI risk stratification tool for elective EVAR patients.

METHODS

We queried the Blue Cross Blue Shield of Michigan Cardiovascular Consortium (BMC2) database for elective EVAR patients and excluded those on dialysis, with a history of renal transplant, death during procedure, and without creatinine measures. Association with CA-AKI (rise in creatinine > 0.5 mg/dL) was tested using mixed effects logistic regression. Variables associated with CA-AKI were used to generate a predictive model via a single classification tree. The variables selected by the classification tree were then validated by fitting a mixed effects logistic regression model into the Vascular Quality Initiative (VQI) dataset.

RESULTS

Our derivation cohort included 7,043 patients, 3.5% of whom developed CA-AKI. After multivariate analysis, age (OR 1.021, 95% CI 1.004-1.040), female sex (OR 1.393, CI 1.012-1.916), GFR < 30 ml/min (OR 5.068, CI 3.255-7.891), current smoking (OR 1.942, CI 1.067-3.535), COPD (OR 1.402, CI 1.066-1.843), maximum AAA diameter (OR 1.018, CI 1.006-1.029), and presence of iliac artery aneurysm (OR 1.352, CI 1.007-1.816) were associated with increased odds of CA-AKI. Our risk prediction calculator demonstrated that patients with a GFR <30 ml/min, females, and patients with a maximum AAA diameter of > 6.9 cm are at higher risk of CA-AKI after EVAR. Using the VQI dataset (N = 62,986), we found that GFR <30 ml/min (OR 4.668, CI 4.007-5.85), female sex (OR 1.352, CI 1.213-1.507), and maximum AAA diameter > 6.9 cm (OR 1.824, CI 1.212-1.506) were associated with increased risk of CA-AKI after EVAR.

CONCLUSIONS

Herein, we present a simple and novel risk assessment tool that can be used pre-operatively to identify patients at risk of CA-AKI after EVAR. Patients with a GFR < 30 ml/min, maximum AAA diameter > 6.9 cm, and females who are undergoing EVAR may be at risk for CA-AKI after EVAR. Prospective studies are needed to determine the efficacy of our model.

A simplified acute kidney injury predictor following endovascular aortic repair: ACEF score

OBJECTIVES

Treatment of abdominal aortic aneurysms (AAA) with endovascular aortic repair (EVAR) has become quite common in recent years. This method, which has many advantages compared to the open surgical procedure, also has some complications. One of these complications is acute kidney injury (AKI). ACEF (age, creatinine, and ejection fraction) score, which is gaining popularity, can be an easy-to-use and cost-effective method in detecting this condition that causes increased morbidity and mortality. We aimed to evaluate whether this ACEF score may predict a development of AKI in patients who underwent EVAR.

METHODS

A total of 133 consecutive patients with AAA who underwent EVAR were analyzed. The primary endpoint of the study was the development of AKI. The best cut-off value for the ACEF score to predict the development of AKI was calculated and according to this value, the patients were divided into two groups as those with high ACEF scores and those with low ACEF scores. ACEF score was calculated by the formula of age/EF + 1 (if baseline creatinine > 2 mg/dL).

RESULTS

After the exclusion criteria, a total of 118 patients were included in the study, and 20 (16.9%) of them developed AKI after EVAR. In the ROC curve analysis, a cut-off value of 1.34 was found for the ACEF score, and scores above this value were found to be independent predictors of AKI development after EVAR. In addition to the ACEF score, the contrast media volume was also found to be an independent predictor of the development of AKI.

CONCLUSION

In conclusion, ACEF is a simple and effective scoring system in patients undergoing EVAR. To the best our knowledge, our study is the first study which applies ACEF score to predict AKI in EVAR patients.

Selection criterion for endovascular aortic repair in those with chronic kidney disease

OBJECTIVE

Endovascular aortic repair (EVAR) is the preferred method of repair for abdominal aortic aneurysms (AAAs). However, patients with advanced chronic kidney disease (CKD) are a high-risk group, and it is unknown which patients with CKD benefit from EVAR vs continued surveillance. The purpose of this study was to identify which patients with advanced CKD may benefit from EVAR.

METHODS

The Vascular Quality Initiative Database was utilized to identify elective EVARs for AAAs. Patients were excluded if they underwent urgent or emergent repairs. CKD stages were categorized based on preoperative estimated glomular filtration rate (eGFR) and dialysis status. Predicted 1-year mortality of untreated AAAs was calculated by modifying a validated comorbidity score that predicts 1-year mortality (Gagne Index) without repair. The primary outcome was actual 1-year mortality, which was compared with the predicted 1-year mortality without repair.

RESULTS

A total of 34,926 patient met study criteria. There were differences in Gagne Indices among the varying classes of CKD. Patients with CKD 4 and CKD 5 had the highest 1-year mortality rates, followed by CKD 3b, which was significantly higher than those with CKD 1 and CKD 2. Patients with CKD 4 had no differences between actual 1-year mortality with EVAR and predicted 1-year survival without EVAR across all AAA sizes. Those with CKD 5 had worse actual 1-year survival with EVAR than predicted 1-year survival without EVAR for AAAs <5.5 cm. Patients with CKD 5 only experienced an actual mortality benefit with EVAR compared with predicted 1-year mortality without EVAR for AAAs ≥7.0 cm.

CONCLUSION

The current data suggest that patients with CKD 3b, 4, and 5 represent a high-risk group who may not benefit from elective EVAR utilizing traditional size criteria. Patients with CKD 4 and 5 with AAAs <5.5 cm do not benefit from elective EVAR. In patients with CKD 5, elective EVAR may need to be reserved for AAAs ≥7.0 cm unless there are other concerning anatomic characteristics.

Use of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers increases the risk of postoperative acute kidney injury after elective endovascular abdominal aortic aneurysm repair

BACKGROUND

Endovascular abdominal aortic aneurysm repair (EVAR) is the major treatment for abdominal aortic aneurysm (AAA); however, EVAR still carries a considerable risk of acute kidney injury (AKI). The present study aimed to investigate the risk factors for AKI after elective EVAR procedures.

METHODS

This was a retrospective observational study. Eligible patients who underwent EVAR from September 2011 to March 2019 in West China Hospital were included. The primary outcome was the occurrence of AKI within two days after EVAR, which was defined by the Kidney Disease Improving Global Outcomes Clinical Practice Guideline. Demographics, comorbidities, medications, laboratory tests, anatomical parameters of AAA, and relative operative details were collected as variables. Univariable and multivariable logistic regression analyses were applied to identify the risk factors among variables, and covariate interactions were further assessed.

RESULTS

A total of 679 eligible patients were included. The incidence of postoperative AKI was 8.2% (56/679) in the whole cohort, and it was associated with a lower 5-year survival rate (63.5% vs . 80.9%; χ 2  = 4.10; P  = 0.043). The multivariable logistic regression showed that chronic kidney disease (OR, 5.06; 95% CI: 1.43-17.95; P  = 0.012), angiotensin-converting enzyme inhibitors (ACEIs)/angiotensin receptor blockers (ARBs) (OR, 2.60; 95% CI: 1.17-5.76; P  = 0.019), and short neck (OR, 2.85; 95% CI: 1.08-7.52; P  = 0.035) were independent risk factors for postoperative AKI. In the covariate interaction analysis, the effect of ACEIs/ARBs use on postoperative AKI was similar across all subgroups ( P  > 0.05), thereby suggesting a robust effect of ACEIs/ARBs use in all patients undergoing elective endovascular abdominal aortic aneurysm repair.

CONCLUSIONS

Postoperative AKI was associated with lower survival rate, and the use of ACEIs/ARBs was the only adjustable independent risk factor. Clinicians should consider withdrawing ACEIs/ARBs in high-risk patients undergoing elective endovascular abdominal aortic aneurysm repair to prevent postoperative AKI.

Incidence, Prognostic Significance, and Risk Factors of Acute Kidney Injury Following Elective Infrarenal and Complex Endovascular Aneurysm Repair

OBJECTIVE

Acute kidney injury (AKI) is a well known complication following cardiovascular procedures. The objective was to assess the incidence, risk factors, and prognostic significance of AKI after infrarenal endovascular aneurysm repair (EVAR) and complex EVAR (cEVAR; fenestrated or branched EVAR).

METHODS

Consecutive patients undergoing elective infrarenal EVAR or cEVAR between 2000 and 2018 in two large teaching hospitals in the Netherlands were included. AKI was determined by serum creatinine levels increasing > 1.5 times or by an absolute increase of 26.5 mmol/L from baseline value (KDIGO criteria). The primary outcome was incidence of peri-operative AKI development. Secondary outcomes included mid-term renal function (RIFLE criteria), overall survival, and risk factors for AKI development. To determine survival and risk factors for AKI, multivariable Cox regression and logistic regression analyses were performed, accounting for pre-operative renal function and other confounders.

RESULTS

In total, 540 patients who underwent infrarenal EVAR with 147 patients who underwent cEVAR also included. The incidence of AKI was 8.7% (n = 47) in infrarenal EVAR patients and 23% (n = 34) in cEVAR patients (fenestrated EVAR 18%; branched EVAR 38%). In contrast to patients without AKI, the renal function of surviving patients with AKI remained significantly reduced at six weeks and did not return to pre-operative values following infrarenal EVAR (three year estimated glomerular filtration rate [eGFR] 59.3 ± 23.1 mL/min/1.73m2vs. pre-operative eGFR 74.0 ± 21.7 mL/min/1.73m2; p = .006) or following cEVAR (three year eGFR 52.0 ± 23.7 mL/min/1.73m2vs. pre-operative eGFR 65.4 ± 18.6 mL/min/1.73m2; p = .082). After risk adjusted analysis, compared with non-AKI, post-operative AKI development was associated with a higher three year mortality rate following both infrarenal and cEVAR (infrarenal EVAR mortality hazard ratio [HR 1.6, 95% confidence interval [CI] 1.01 - 2.7 [p = .046]; cEVAR mortality HR 2.4, 95% CI 1.1 - 5.2 [p = .033]). Following multivariable logistic regression, pre-operative chronic kidney disease (eGFR < 60 mL/min/1.73m2; odds ratio [OR] 2.2, 95% CI 1.03 - 4.8) and neck diameter (OR 1.1, 95% CI 1.01 - 1.2) were significantly associated with AKI following infrarenal EVAR, whereas for cEVAR only contrast volume (OR 1.1, 95% CI 1.0 - 1.2]) was found to be statistically significantly associated with AKI.

CONCLUSION

AKI is a well described complication following infrarenal EVAR and is common after cEVAR. As AKI seems to be associated with permanent renal deterioration and lower survival, efforts to prevent AKI are essential. Future studies are required to assess what factors are associated with a higher risk of developing AKI following cEVAR.

Editor's Choice - Sex Specific Outcomes After Complex Fenestrated and Branched Endovascular Aortic Repair: A Systematic Review and Meta-analysis

OBJECTIVE

As females are at higher mortality risk after endovascular aortic repair, this study aimed to compare the 30-day and 12-month mortality, morbidity, and re-intervention rates between the sexes, treated with fenestrated or branched endovascular aortic repair (F/BEVAR).

DATA SOURCES

A search of the English literature, via Ovid, using MEDLINE, Embase, and CENTRAL, up to 30 July 2021, was performed.

REVIEW METHODS

This meta-analysis was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement, and its protocol was registered in PROSPERO (CRD42021273418). Observational studies (2010-21), with ≥ 20 patients, reporting on sex specific outcomes (mortality, acute kidney injury [AKI], spinal cord ischaemia [SCI], and re-intervention, after F/BEVAR), were considered eligible. Risk of bias in the studies was assessed using ROBINS-I, and evidence quality was assessed using GRADE. The primary outcome was the sex specific 30-day mortality rate, AKI, SCI, and re-intervention rates; secondary outcomes were survival and freedom from re-intervention at 12 months after F/BEVAR. The outcomes were summarised as odds ratio (OR) with 95% confidence intervals (CIs).

RESULTS

Four retrospective and one prospective study (2 421 patients; 26% females) were included. The 30-day mortality rate was 12% in females vs. 3% in males (OR 2.65, 95% CI 1.79 - 3.92; Ι² = 0%). The 30-day AKI, SCI, and re-intervention rates were similar (OR 1.45, 95% CI 1.03 - 2.03; Ι² = 0%; OR 1.86, 95% CI 1.27 - 2.74; Ι² = 38%; and OR 1.06, 95% CI 0.66 - 1.77; Ι² = 0%, respectively). The 12-month survival rate was lower in females (OR 0.95, 95% CI 0.91 - 0.99; Ι² = 38%). When excluding 30-day deaths, there was no difference in 12-month survival between sexes (OR 0.99, 95% CI 0.95 - 1.02; Ι² = 32%). The 12-month freedom from re-intervention was similar between sexes (OR 0.87, 95% CI 0.75 - 1.01; Ι² = 0%).

CONCLUSION

Female patients treated by F/BEVAR may present worse outcomes in terms of 30-day and 12-month survival. The high peri-operative mortality rate remains an issue. When excluding 30-day deaths, the 12-month survival rate was similar between the sexes. Early morbidity and re-intervention rates were comparable.

Open Abdominal Aortic Aneurysm Surgery and Renal Dysfunction; Association of Demographic and Clinical Variables with Proximal Clamp Location

BACKGROUND

While cross-clamp site is a known risk factor for postoperative acute and chronic renal dysfunction following open abdominal aortic aneurysm surgery (AAA), the additive impact of patient demographic and clinical factors is lacking. In this study, we investigated the impact of body mass index (BMI), surgical duration and aneurysm diameter on the association between proximal cross-clamp location and postoperative renal dysfunction.

METHODS

In this study, we conducted a retrospective analysis of 4,197 patients undergoing open AAA surgery between 2011 and 2018 using data housed in the American College of Surgeons National Safety Quality Improvement Program (ACS-NSQIP) database. The primary outcome was renal dysfunction, which was defined as patients requiring dialysis within 30 days or patients with ≥2 mg/dL rise in creatinine from baseline. We assessed the incidence of renal dysfunction with regard to clamp location and subsequently used multivariable logistic regression to assess clinical and demographic factors associated with renal dysfunction. We used a regression model to plot the association of BMI, surgical duration, and aneurysm diameter with an adjusted probability of postoperative acute and chronic renal dysfunction for individual cross-clamp locations.

RESULTS

Of the 4,197 patients analyzed, 405 patients (9.6%) developed renal dysfunction within 30 days with 287 patients requiring dialysis. Patients with supraceliac clamp location had the highest incidence of renal dysfunction (20.4%). Our data showed a significant association of renal dysfunction with higher BMI patients [OR 1.04 (1.02, 1.07), P = 0.001], longer operative times [OR1.01 (1.01, 1.02), P < 0.001], clamp location between the superior mesenteric artery (SMA) and renal artery [OR 1.80 (1.17, 2.78), P = 0.007] and supraceliac clamp location [OR 2.47 (1.62, 3.76), P < 0.001].

CONCLUSIONS

The incidence of renal dysfunction increases with suprarenal clamps. Patients with higher BMI, longer operative times, and increasing aneurysm diameter, and a suprarenal clamp have a significantly increased risk of renal dysfunction compared to those who also had a suprarenal clamp but lower BMI, shorter operative times and smaller aneurysm diameter.

Incidence of Contrast-Induced Nephropathy and Post-Operative Outcomes in Patients Undergoing Chimney Endovascular Aortic Aneurysm Repair

Chimney endovascular aortic aneurysm repair (ch-EVAR) has become a valid alternative to treat complex aneurysms but the occurrence of contrast-induced kidney injury (CI-AKI) is poorly known. This study investigated the incidence and the impact of CI-AKI on post-operative outcomes after ch-EVAR. Consecutive patients who underwent ch-EVAR between July 2010 and 2021 were retrospectively included. CI-AKI was defined based on plasma creatinine levels within 7 days after the intervention according to the "Kidney Disease Improving Global Outcomes" (KDIGO) classification. Among 102 patients included, CI-AKI occurred in 14 cases (13.7%). The 30-day post-operative mortality and complications were significantly higher in patients who developed CI-AKI compared with those who did not (50 vs 9.1%, P = .001 and 57.1 vs 20.5%, P = .007). Over a median follow-up of 24 months (3-39), overall mortality was also significantly higher (78.6 vs 33.0%, P = .002). The pre-operative platelet-to-lymphocyte ratio (PLR) was significantly higher in patients who developed CI-AKI (224.5 vs 147.6, P = .008). CI-AKI is frequent after ch-EVAR and is associated with worse post-operative outcomes. This should increase awareness of clinicians to optimize preventive and therapeutic strategies.

Pre-Operative Moderate to Severe Chronic Kidney Disease is Associated with Worse Short-Term and Mid-Term Outcomes in Patients Undergoing Fenestrated-Branched Endovascular Aortic Repair

OBJECTIVE

To review experience of fenestrated-branched endovascular aortic repair (F-BEVAR) for pararenal/thoraco-abdominal aortic aneurysms (PRAA/TAAA) and to assess the association between pre-operative moderate to severe chronic kidney disease (CKD) and post-operative outcomes.

METHODS

All consecutive patients undergoing (elective and non-elective) F-BEVAR at a single centre (1 January 2011 - 1 July 2019) were identified. Renal function was calculated as the estimated glomerular filtration rate (eGFR) using the Modification of Diet in Renal Disease formula. Accordingly, presence of moderate to severe CKD was defined as eGFR < 60 mL/min/1.73m².

RESULTS

Overall, 202 consecutive patients (mean age 72 ± 8 years; 25% women) underwent F-BEVAR for the treatment of PRAA/TAAA during the study period. Of these, 51 had a history of moderate to severe CKD (none on chronic haemodialysis). No statistically significant differences were found in demographics and major comorbidities between patients with or without a history of CKD. The overall peri-operative mortality rate was 2%, without statistically significant differences between study groups (p = .26). Patients with prior CKD had statistically significantly higher rates of acute kidney injury (AKI) (37% vs. 12%, p < .001). At three years, overall survival was statistically significantly lower in patients with history of CKD compared with those without pre-operative CKD (57% vs. 82%, p = .010). Similarly, freedom from renal function decline at three years was statistically significantly poorer in patients with prior history of CKD compared with those without pre-operative CKD (43% vs. 80%, p = .020). In a multivariable analysis CKD was independently associated with higher odds of peri-operative AKI (OR 2.8, 95% CI 1.9 - 5.8, p = .030), renal function decline (OR 4.9, 95% CI 1.7 - 9.2, p = .003), and all cause mortality (HR 3.2, 95% CI 1.2 - 8.6, p = .020).

CONCLUSION

Despite low peri-operative mortality rates that are comparable to patients with unimpaired renal function, occurrence of AKI was statistically significantly higher in subjects with pre-existing moderate to severe CKD. History of CKD was independently associated to renal function decline and poorer midterm survival.

Contrast-induced nephropathy in non-cardiac vascular procedures, a narrative review: Part 1

Contrast-induced nephropathy (CIN) is an important complication of iodinated contrast medium (CM) administration, which is associated with both short- and long-term adverse outcomes (e.g., cardiorenal events, longer hospital stay, and mortality). CIN has been mainly studied in relation to cardiac procedures, but it can also occur following non-cardiac vascular interventions. This is Part 1 of a narrative review summarizing the available literature on CIN after non-cardiac vascular diagnostic or therapeutic procedures for aortic aneurysm and carotid stenosis. We discuss the definition, pathophysiology, incidence, risk factors, biomarkers, and consequences of CIN in these settings, as well as preventive strategies and alternatives to limit iodinated CM use. Physicians and vascular surgeons should be aware of CM-related adverse events and the potential strategies to avoid them. Clearly, more research in this important field is required.

Hyperbaric Oxygen Preconditioning Upregulates Heme OxyGenase-1 and Anti-Apoptotic Bcl-2 Protein Expression in Spontaneously Hypertensive Rats with Induced Postischemic Acute Kidney Injury

Renal ischemia and reperfusion (I/R) injury is the most common cause of acute kidney injury (AKI). Pathogenesis of postischemic AKI involves hemodynamic changes, oxidative stress, inflammation process, calcium ion overloading, apoptosis and necrosis. Up to date, therapeutic approaches to treat AKI are extremely limited. Thus, the aim of this study was to evaluate the effects of hyperbaric oxygen (HBO) preconditioning on citoprotective enzyme, heme oxygenase-1 (HO-1), pro-apoptotic Bax and anti-apoptotic Bcl-2 proteins expression, in postischemic AKI induced in normotensive Wistar and spontaneously hypertensive rats (SHR). The animals were randomly divided into six experimental groups: SHAM-operated Wistar rats (W-SHAM), Wistar rats with induced postischemic AKI (W-AKI) and Wistar group with HBO preconditioning before AKI induction (W-AKI + HBO). On the other hand, SHR rats were also divided into same three groups: SHR-SHAM, SHR-AKI and SHR-AKI + HBO. We demonstrated that HBO preconditioning upregulated HO-1 and anti-apoptotic Bcl-2 protein expression, in both Wistar and SH rats. In addition, HBO preconditioning improved glomerular filtration rate, supporting by significant increase in creatinine, urea and phosphate clearances in both rat strains. Considering our results, we can also say that even in hypertensive conditions, we can expect protective effects of HBO preconditioning in experimental model of AKI.

Acute Renal Failure/Acute Kidney Injury (AKI) Associated with Endovascular Procedures

AKI is one of the most common yet underdiagnosed postoperative complications that can occur after any type of surgery. Contrast-induced nephropathy (CIN) is still poorly defined and due to a wide range of confounding individual variables, its risk is difficult to determine. CIN mainly affects patients with underlying chronic kidney disease, diabetes, sepsis, heart failure, acute coronary syndrome and cardiogenic shock. Further research is necessary to better understand pathophysiology of contrast-induced AKI and consequent implementation of effective prevention and therapeutic strategies. Although many therapies have been tested to avoid CIN, the only potent preventative strategy involves aggressive fluid administration and reduction of contrast volume. Regardless of surgical technique—open or endovascular—perioperative AKI is associated with significant morbidity, mortality and cost. Endovascular procedures always require administration of a contrast media, which may cause acute tubular necrosis or renal vascular embolization leading to renal ischemia and as a consequence, contribute to increased number of post-operative AKIs.

Outcomes of fenestrated-branched endovascular aortic repair in patients with a solitary functional kidney

OBJECTIVE

The aim of this study was to evaluate outcomes of fenestrated-branched endovascular aortic repair (F-BEVAR) of pararenal abdominal aortic aneurysms or thoracoabdominal aortic aneurysms (TAAAs) in patients with a solitary functional kidney (SFK).

METHODS

We analyzed the outcomes of 287 consecutive patients (206 male; mean age, 74 ± 8 years old) enrolled in a prospective nonrandomized study to investigate use of F-BEVAR for treatment of patients with pararenal abdominal aortic aneurysms or TAAAs between 2013 and 2018. Outcomes were analyzed in patients with solitary kidney (functional or congenital) and compared with control patients who had two functioning kidneys. Acute kidney injury (AKI) was defined using Risk, Injury, Failure, Loss of kidney function, and End-stage renal disease criteria, and renal function deterioration (RFD) was defined by a decline in estimated glomerular filtration the estimated glomerular filtration rate of more than 30% from baseline. End points included 30-day mortality and major adverse events, AKI, freedom from RFD, and patient survival.

RESULTS

There where 30 patients (10%) with a SFK and 257 patients with two functioning kidneys. Patients with a SFK were younger and had significantly (P < .05) higher baseline creatinine (+0.3 mg/dL), lower estimated glomerular filtration rate (-16 mL/minute/1.73 m²) and more often had stage III to V chronic kidney disease (73% vs 43%). There were no differences in cardiovascular risk factors and aneurysm extent. Technical success was achieved in 98.9% of patients with SFK and in 99.8% of controls (P = .10). At 30 days, there was no significant differences in mortality (0% vs 1%) and major adverse events (40% vs 24%; P = .08), including rates of AKI (20% vs 12%) and new-onset dialysis (3% vs 1%) between patients with a SFK and the control group, respectively. Mean follow-up was 18 ± 15 months. At 2 years, there was no difference (P = .36) in patient survival (92 ± 5% vs 84 ± 3%) and freedom from RFD (100 ± 0% vs 84 ± 3%) for patients with SFK and controls, respectively. Presence of a SFK was not a predictor for AKI or RFD. By multivariable analysis, estimated blood loss of more than 1 L (odds ratio [OR], 2.9; P = .04) and total fluoroscopy time (OR, 1.8; P = .05) were predictors for AKI, and postoperative AKI (OR, 4.9; P < .001), renal branch occlusion/stenosis (OR, 3.1; P = .001), and Crawford extent II TAAA (OR, 2.4; P = .007) were predictors for RFD.

CONCLUSIONS

Despite the worse baseline renal function, F-BEVAR is safe and effective with nearly identical outcomes in patients with a SFK as compared with patients with two functioning kidneys. Development of postoperative AKI is the most important predictor for RFD.

Statin loading in cardiovascular surgery: never too early to treat

PURPOSE OF REVIEW

The effects of statin loading before, during or after vascular interventions on cardiovascular and renal outcomes are discussed. Furthermore, the selection of optimal statin type and dose, according to current evidence or guidelines, is considered. The importance of treating statin intolerance and avoiding statin discontinuation is also discussed.

RECENT FINDINGS

Statin loading has been shown to beneficially affect cardiovascular outcomes, total mortality and/or contrast-induced acute kidney injury, in patients undergoing vascular procedures such as percutaneous coronary intervention (PCI), coronary artery bypass grafting (CABG), carotid endarterectomy (CEA), carotid artery stenting, endovascular aneurysm repair, open abdominal aortic aneurysms (AAA) repair and lower extremities vascular interventions. High-dose statin pretreatment is recommended for PCI and CABG according to current guidelines. Statin discontinuation should be avoided during acute cardiovascular events and vascular interventions; adequate measures should be implemented to overcome statin intolerance.

SUMMARY

Statin loading is an important clinical issue in patients with cardiac and noncardiac vascular diseases, including carotid artery disease, peripheral artery disease and AAA, undergoing vascular interventions. Cardiologists and vascular surgeons should be aware of current evidence and implement guidelines in relation to statin loading, discontinuation and intolerance.

Lipids: a personal view of the past decade

The past decade has witnessed considerable progress in the field of lipids. New drugs have been "rapidly" developed and some of these drugs have already been evaluated in event-based large trials. This evidence has led to the guidelines recommending new, more aggressive treatment goals for low-density lipoprotein cholesterol (LDL-C) levels. Although LDL-C remains the principal goal for cardiovascular disease (CVD) risk reduction, there has also been considerable interest in other lipid variables, such as high-density lipoprotein cholesterol, triglycerides, and lipoprotein(a). Statin intolerance is now considered a very important topic in daily clinical practice. This has resulted in more attention focusing on non-statin drugs [e.g., ezetimibe and proprotein convertase subtilisin/kexin 9 (PCSK9) inhibitors] and statin-related side effects. The latter mainly involve muscles, but there is also a need to consider other adverse effects associated with statin use (e.g., new onset diabetes). New specific areas of statin use have attracted interest. For example, statin-loading before procedures (e.g., coronary stenting), the prevention of stroke, and the treatment of non-alcoholic fatty liver disease (NAFLD). Statins will remain the most widely used drugs to treat dyslipidaemia and decrease CVD risk. However, we also need to briefly consider some other lipid-lowering drugs, including those that may become available in the future.

Long-term risk of adverse outcomes after acute kidney injury: a systematic review and meta-analysis of cohort studies using consensus definitions of exposure

Reliable estimates of the long-term outcomes of acute kidney injury (AKI) are needed to inform clinical practice and guide allocation of health care resources. This systematic review and meta-analysis aimed to quantify the association between AKI and chronic kidney disease (CKD), end-stage kidney disease (ESKD), and death. Systematic searches were performed through EMBASE, MEDLINE, and grey literature sources to identify cohort studies in hospitalized adults that used standardized definitions for AKI, included a non-exposed comparator, and followed patients for at least 1 year. Risk of bias was assessed by the Newcastle-Ottawa Scale. Random effects meta-analyses were performed to pool risk estimates; subgroup, sensitivity, and meta-regression analyses were used to investigate heterogeneity. Of 4973 citations, 82 studies (comprising 2,017,437 participants) were eligible for inclusion. Common sources of bias included incomplete reporting of outcome data, missing biochemical values, and inadequate adjustment for confounders. Individuals with AKI were at increased risk of new or progressive CKD (HR 2.67, 95% CI 1.99-3.58; 17.76 versus 7.59 cases per 100 person-years), ESKD (HR 4.81, 95% CI 3.04-7.62; 0.47 versus 0.08 cases per 100 person-years), and death (HR 1.80, 95% CI 1.61-2.02; 13.19 versus 7.26 deaths per 100 person-years). A gradient of risk across increasing AKI stages was demonstrated for all outcomes. For mortality, the magnitude of risk was also modified by clinical setting, baseline kidney function, diabetes, and coronary heart disease. These findings establish the poor long-term outcomes of AKI while highlighting the importance of injury severity and clinical setting in the estimation of risk.

Predictors of Acute Kidney Injury Following Elective Open and Endovascular Aortic Repair for Abdominal Aortic Aneurysm

Objective: To investigate the predictors of acute kidney injury (AKI) following surgery for abdominal aortic aneurysm.

Materials and Methods: Subjects were 642 non-hemodialysis patients (open aortic repair [OAR] group, n=453; endovascular aortic repair [EVAR] group, n=189) who underwent elective surgery between 2009 and 2015. AKI was assessed according to the Kidney Disease Improving Global Outcomes criteria. In-hospital mortality and incidence of AKI were compared between the OAR and EVAR groups. The effect of AKI on outcomes and predictors of AKI were examined in both groups.

Results: In-hospital mortalities were 0.7% (3/453) in the OAR group and 0.5% (1/189) in the EVAR group. The incidence of AKI increased in the OAR group (14.1% vs. 3.7%, P<0.01). In the OAR group, in-hospital mortality (0% vs. 4.7%, P<0.01) increased in patients with AKI. In the OAR group, hemoglobin level <10 g/dL, estimated glomerular filtration rate <60 mL/min/1.73 m², operation time >300 min, history of ischemic heart disease, and amount of bleeding >1,000 mL were predictors of AKI. In the EVAR group, amount of transfusion>1,000 mL was a predictor of AKI, but AKI was not found to worsen outcomes.

Conclusion: AKI affected outcomes of OAR. Knowledge of predictors may optimize perioperative care.

Severe Infrarenal Atheroma Load in Open Aortic Aneurysm Repair Is Not a Risk Factor for Postoperative Acute Kidney Injury

BACKGROUND

Acute kidney injury (AKI) after open aortic repair is subject to multiple patient- and operation-related variables. Hostile neck morphology in open aneurysm repair is thought to contribute to this AKI risk postoperatively. The aim of this study was to evaluate if large neck atheroma is a possible risk factor in the postoperative development of AKI.

METHODS

Retrospectively 137 patients were evaluated for neck atheroma and AKI incidence. Atheroma load measurements were performed by 2 different techniques. Results were compared, and secondly a univariate analysis was performed for multiple additional risk factors regarding AKI occurrence.

RESULTS

Significant (>30%) neck atheroma was not associated with a higher risk for developing AKI (odds ratio [OR]: 1.81; 95% confidence intervals: 0.74-4.44). Overall incidence of AKI based upon Acute Kidney Injury Network criteria was 19.7%. In univariate analysis coronary artery disease and the presence of a renal artery stenosis were both significantly associated with AKI (OR: 2.38, 3.31, respectively) as well as the use of B-blockers and angiotensin converting enzyme inhibitors (OR 3.05, 2.48, respectively).

CONCLUSIONS

Cross-clamping in case of significant neck atheroma during open aortic aneurysm repair is not associated with increased risk of AKI. Defining high-risk patients based on additional risk factors must be a part of preoperative patient selection.