Comparison of Outcomes for Open Abdominal Aortic Aneurysm Repair and Endovascular Repair in Patients With Chronic Renal Insufficiency

Contemporary outcomes of open thoracoabdominal aortic aneurysm repair in the endovascular era

OBJECTIVE

Open thoracoabdominal aortic aneurysm (TAAA) repair has been associated with high morbidity and mortality before the endovascular era, when repair options were limited. Our institution developed a multidisciplinary protocol to standardize patient selection, operative technique, and postoperative care to improve outcomes for open repairs. This study aimed to evaluate the protocol's preliminary benefits by comparing the outcomes of open TAAA repair on the protocol vs off the protocol.

METHODS

A retrospective review of consecutive patients who underwent TAAA repair at a single institution from 2013 to 2023 was completed. Patients who underwent open repair were included and stratified by use of the protocol. The primary outcome was a composite of TAAA life-altering events, including in-hospital mortality, spinal cord ischemia with paraplegia, new onset of dialysis, or stroke. Secondary outcomes included each individual component, length of stay, and nonhome discharge.

RESULTS

During the study period, 220 patients underwent TAAA repair at our institution, 190 endovascular and 30 open. There were 14 in the protocol group and 16 in the nonprotocol group. Patient demographics were similar between groups with an overall mean age of 46 years. A connective tissue disorder was present in 64% and 50% (P = .431) of protocol and nonprotocol patients, respectively. The majority of the patients in both groups presented with extent II TAAA (64% vs 75%). The composite end point occurred in 0% of the protocol group vs 38% of the nonprotocol group (P = .010). Secondary outcomes were dialysis (0% vs 19%; P = .23), paraplegia (0% vs 19%; P = .232), stroke (0% vs 0%), in-hospital mortality (0% vs 13%; P = .171), and nonhome discharge (7% vs 50%; P = .012). The median postoperative length of stay was 8 days vs 15 days (P = .038).

CONCLUSIONS

In the endovascular era, open TAAA repair can be performed with encouraging outcomes when particular attention is given to patient selection, surgical technique, and postoperative care, with rates of mortality, paraplegia, renal failure, and length of stay that rival endovascular repair.

Incorporating machine learning and PPI networks to identify mitochondrial fission-related immune markers in abdominal aortic aneurysms

Purpose

The aim of this study is to investigate abdominal aortic aneurysm (AAA), a disease characterised by inflammation and progressive vasodilatation, for novel gene-targeted therapeutic loci.

Methods

To do this, we used weighted co-expression network analysis (WGCNA) and differential gene analysis on samples from the GEO database. Additionally, we carried out enrichment analysis and determined that the blue module was of interest. Additionally, we performed an investigation of immune infiltration and discovered genes linked to immune evasion and mitochondrial fission. In order to screen for feature genes, we used two PPI network gene selection methods and five machine learning methods. This allowed us to identify the most featrue genes (MFGs). The expression of the MFGs in various cell subgroups was then evaluated by analysis of single cell samples from AAA. Additionally, we looked at the expression levels of the MFGs as well as the levels of inflammatory immune-related markers in cellular and animal models of AAA. Finally, we predicted potential drugs that could be targeted for the treatment of AAA.

Results

Our research identified 1249 up-regulated differential genes and 3653 down-regulated differential genes. Through WGCNA, we also discovered 44 genes in the blue module. By taking the point where several strategies for gene selection overlap, the MFG (ITGAL and SELL) was produced. We discovered through single cell research that the MFG were specifically expressed in T regulatory cells, NK cells, B lineage, and lymphocytes. In both animal and cellular models of AAA, the MFGs' mRNA levels rose.

Conclusion

We searched for the AAA novel targeted gene (ITGAL and SELL), which most likely function through lymphocytes of the B lineage, NK cells, T regulatory cells, and B lineage. This analysis gave AAA a brand-new goal to treat or prevent the disease.

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.

Chronic kidney disease impacts outcomes after abdominal aortic aneurysm repair

OBJECTIVE

Chronic kidney disease (CKD) and end-stage renal disease are traditionally associated with worse outcomes after endovascular and open repair of abdominal aortic aneurysm (AAA). This study stratifies outcomes of AAA repair by approach, CKD severity, and dialysis dependence.

METHODS

All patients undergoing elective infrarenal open aneurysm repair (OAR) and endovascular aortic repair (EVAR) with preoperative renal function data captured by the Vascular Quality Initiative between January 2003 and September 2020 were analyzed. Patients were stratified by CKD class as follows: CKD stages 1 and 2, CKD stage 3a, CKD stage 3b, CKD stages 4 and 5, and dialysis. Primary outcomes were perioperative and 1-year mortality. Predictors of survival were identified by Cox multivariate regression models.

RESULTS

In total, 53,867 elective AAA repairs were identified: 5396 (10%) OARs and 48,471 (90%) EVARs. Most patients were White (90%) and male (81%), with a mean age of 73 ± 9 years. Patients who underwent EVAR were older and had more comorbidities. The use of elective EVAR for AAA increased from 52% in 2003 to 91% in 2020 (P < .001). The OAR cohort had more perioperative complications and short-term mortality. The CKD 1 and 2 group had the highest 1-year survival compared with the other groups after both OAR and EVAR. On Cox regression analysis, after EVAR, compared with CKD 1 and 2, worsening CKD stage (CKD 3a: hazard ratio [HR], 1.25; 95% confidence interval [CI], 0.93-1.68; P = .13; CKD 3b: HR, 1.74; 95% CI, 1.23-2.45; P < .050; CKD 4-5: HR, 3.23; 95% CI, 2.13-4.88; P < .001), and dialysis (HR, 4.48; 95% CI, 1.90-10.6; P < .001) were independently associated with worse 1-year survival rates. After OAR, compared with CKD 1 and 2, worsening CKD stage (CKD 3a: HR, 1.08; 95% CI, 0.96-1.20; P = .20; CKD 3b: HR, 1.60; 95% CI, 1.41-1.81; P < .001; CKD 4-5: HR, 2.85; 95% CI, 2.39-3.41; P < .001), and dialysis (HR, 3.79; 95% CI, 3.01-4.76; P < .001) were independently associated with worse 1-year survival rates.

CONCLUSIONS

Regardless of the treatment approach, CKD severity is an important predictor of perioperative and 1-year mortality rates after infrarenal AAA repair and may reflect the natural history of CKD. Open repair is associated with high perioperative mortality risk in patients with CKD stages 4 and 5, as well as end-stage renal disease. Individualization of patient decision-making is especially important in patients with a glomerular filtration rate of less than 45 and perhaps consideration should be given to raising the threshold for elective AAA repair in these patients. Further studies focusing on appropriate size threshold for repair in these patients may be warranted.

Perioperative care in open aortic vascular surgery: A Consensus Statement by the Enhanced Recovery after Surgery (ERAS®) Society and Society for Vascular Surgery

The Society for Vascular Surgery and the Enhanced Recovery After Surgery (ERAS®) Society formally collaborated and elected an international, multi-disciplinary panel of experts to review the literature and provide evidence-based recommendations related to all of the health care received in the perioperative period for patients undergoing open abdominal aortic operations (both transabdominal and retroperitoneal approaches, including supraceliac, suprarenal, and infrarenal clamp sites, for aortic aneurysm and aortoiliac occlusive disease). Structured around the ERAS® core elements, 36 recommendations were made and organized into preadmission, preoperative, intraoperative, and postoperative recommendations.

Incidence and Risk Factors for Sac Expansion after Endovascular Aneurysm Repair of Abdominal Aortic Aneurysms

Purpose

This study aimed to examine the sac changes after endovascular aneurysm repair (EVAR) in patients with abdominal aortic aneurysms.

Methods

Materials and We examined the aneurysm sac size initially and regularly after surgery in 157 consecutive patients who underwent EVAR in 2009-2019. Contrast-enhanced computed tomography (CT) scans were used as well as ultrasound images with non-enhanced CT scans in the patients with renal insufficiency. Sac expansion (SE) at 3 years was divided into two categories: progressive SE (PSE) defined as continuous sac enlargement of ≥5 mm on serial follow-up images at 1 and 3 years compared with the initial sac and delayed SE (DSE) defined as re-expansion of ≥5 mm compared with the regressed or stable sac at 1 year. The SE rate at 1 and 3 years and the risk factors for SE at 3 years were analyzed using logistic regression.

Results

During a median follow-up of 32.5 months, nine reinterventions in six patients were performed with open conversion (n=5) and endovascular repair (n=4). At 1 year, 112 patients underwent follow-up imaging. SE and sac regression were noted in 4 (3.6%) and 57 (50.9%) patients, respectively. Of the 64 patients with 3-year follow-up images, 16 (25%) exhibited SE (PSE [n=6] and DSE [n=10]). In the multivariable analysis, the risk factors for overall SE at 3 years were endoleaks at 1 year (P=0.006) and renal insufficiency (P=0.003).

Conclusion

During post-EVAR follow-up, patients with any endoleak at 1 year or renal insufficiency must be strictly monitored for SE development.

Fenestrated Endovascular Aneurysm Repair Affords Fewer Renal Complications than Open Surgical Repair for Juxtarenal Abdominal Aortic Aneurysms in Patients with Chronic Renal Insufficiency

OBJECTIVE

Although fenestrated endovascular aneurysm repair (FEVAR) has been associated with lower morbidity and mortality than open surgical repair (OSR) in juxtarenal aneurysms (JAAA), there is a paucity of data in the literature comparing outcomes of the approaches specifically in patients with chronic renal insufficiency (CRI). We hypothesized that benefits of FEVAR over OSR observed in the general patient population may be diminished in CRI patients due to their heightened vulnerability to renal dysfunction stemming from contrast-induced nephropathy. This study compares 30-day outcomes between FEVAR and OSR for JAAA in patients with non-dialysis dependent CRI.

METHODS

All adults with estimated glomerular filtration rate (eGFR) < 60 mL/min (but not requiring dialysis) undergoing elective, non-ruptured JAAA repairs were identified in the American College of Surgeons - National Surgical Quality Improvement (ACS-NSQIP) Targeted EVAR and AAA databases from 2012-2018. JAAA were identified by recorded proximal aneurysm extent. FEVAR patients were identified in the Targeted EVAR database as those receiving the "Cook Zenith Fenestrated" endograft. OSR cases were defined as those that required proximal clamp positions "above one renal" or "between SMA & renals." Infra-renal or supra-celiac proximal clamp placement, or cases involving concomitant renal/visceral revascularization were excluded. Thirty-day outcomes including mortality, major adverse cardiovascular events (MACE), pulmonary, and renal complications were compared between FEVAR and OSR groups.

RESULTS

There were 284 patients with CRI who underwent elective repair of JAAA (FEVAR: 89; OSR: 195). FEVAR patients were significantly older than those undergoing OSR (77.3±7.2 vs. 74.2±7.7, P=0.001) and less likely to be smokers (25.8% vs 42.1%; P = 0.009). Other baseline demographic and pre-operative parameters were comparable between the two groups.Multivariable analysis revealed no significant difference between FEVAR and OSR in 30-day mortality (4.5% vs 4.6%; OR=1.22; 95% CI=0.35 - 4.22; P=0.753) or unplanned re-operation (4.5% vs 5.1%; OR=0.78; 95% CI=0.22 - 2.70; P=0.693). Patients undergoing FEVAR had significantly fewer pulmonary complications (3.4% vs 18.5%; OR=0.12; 95% CI=0.03 - 0.42; P<0.001) and renal dysfunction (3.4% vs 11.8%; OR 0.24 95% CI=0.07 - 0.86; P=0.029) compared to OSR. FEVAR was also associated with significantly shorter ICU and hospital lengths of stay (ICU stay: 0 days vs 3 days, P<0.0001; hospital stay: 3 days vs 8 days, P<0.0001).

CONCLUSION

For patients with chronic renal insufficiency, FEVAR offered improved perioperative renal morbidity compared to OSR without a corresponding mortality benefit. Future studies will be required to determine long term outcomes of this procedure in this vulnerable population.

Abdominal aortic aneurysms

Abdominal aortic aneurysms (AAA) are prevalent among older adults and can cause significant morbidity and mortality if not addressed in a timely fashion. Their etiology remains the topic of continued investigation. Known causes include trauma, infection, and inflammatory disorders. Risk factors include cigarette smoking, advanced age, dyslipidemia, hypertension, and coronary artery disease. The pathophysiology of the disease is related to an initial arterial insult causing a cascade of inflammation and extracellular matrix protein breakdown by proteinases leading to arterial wall weakening. When identified early, aneurysms must be monitored for size, growth rate, and other factors which could increase the risk of rupture. Factors predisposing to rupture include size, active smoking, rate of growth, aberrant biomechanical properties of the aneurysmal sac, and female sex. Medical management includes the control of risk factors that may prevent growth, stabilize the aneurysm, and prevent rupture. Surgical management prevents rupture of high risk aneurysms, most commonly predicted by size. Less frequently, surgical management is required when the aneurysm has ruptured. Surgery involves a multidisciplinary approach to evaluate the patient's risk profile and to develop an operative plan involving either an endovascular or an open surgical repair. The patient must be carefully monitored post-operatively for complications and, in the case of endovascular repairs, for endoleaks. AAA management has evolved rapidly in recent years. Technical and technological advances have transformed the diagnosis and treatment of this disease.

Thirty-day outcomes of open abdominal aortic aneurysm repair by proximal clamp level in patients with normal and impaired renal function

OBJECTIVE

Open surgical repair (OSR) of abdominal aortic aneurysms (AAAs) has often been reserved in contemporary practice for complex aneurysms requiring a suprarenal or supraceliac proximal clamp level. The present study investigated the associated 30-day outcomes of different proximal clamp levels in OSR of complex infrarenal/juxtarenal AAA in patients with normal renal function and those with chronic renal insufficiency (CRI).

METHODS

All patients undergoing elective OSR of infrarenal and juxtarenal AAA were identified in the American College of Surgeons National Surgical Quality Improvement Program-targeted AAA database from 2012 to 2018. The patients were stratified into two cohorts (normal renal function [estimated glomerular filtration rate, ≥60 mL/min] and CRI [estimated glomerular filtration rate, <60 mL/min and no dialysis]) before further substratification into groups by the proximal clamp level (infrarenal, inter-renal, suprarenal, and supraceliac). The 30-day outcomes, including mortality, renal and pulmonary complications, and major adverse cardiovascular event rates, were compared within each renal function cohort between proximal clamp level groups using the infrarenal clamp group as the reference. Supraceliac clamping was also compared with suprarenal clamping.

RESULTS

A total of 1284 patients with normal renal function and 524 with CRI were included in the present study. The proximal clamp levels for the 1808 patients were infrarenal for 1080 (59.7%), inter-renal for 337 (18.6%), suprarenal for 279 (15.4%), and supraceliac for 112 (6.2%). In the normal renal function cohort, no difference was found in 30-day mortality with any clamp level. Increased 30-day acute renal failure was only observed in the supraceliac vs infrarenal clamp level comparison (5.9% vs 1.5%; adjusted odds ratio [aOR], 3.97; 95% confidence interval [CI], 1.04-5.18; P = .044). In the CRI cohort, supraceliac clamping was associated with an increased rate of renal composite complications (22.7% vs 5.6%; aOR, 8.81; 95% CI, 3.17-24.46; P < .001) and ischemic colitis (13.6% vs 3.0%; aOR, 4.78; 95% CI, 1.38-16.62; P = .014) compared with infrarenal clamping and greater 30-day mortality (13.6% vs 2.4%; aOR, 6.00; 95% CI, 1.14-31.55; P = .034) and renal composite complications (22.7% vs 10.8%; aOR, 2.87; 95% CI, 1.02-8.13; P = .047) compared with suprarenal clamping. Suprarenal clamping was associated with greater renal dysfunction (10.8% vs 5.6%; aOR, 2.77; 95% CI, 1.08-7.13; P = .035) compared with infrarenal clamping, with no differences in mortality. No differences were found in 30-day mortality or morbidity for inter-renal clamping compared with infrarenal clamping in either cohort. No differences were found in major adverse cardiovascular events with higher clamp levels in either cohort.

CONCLUSIONS

In elective OSR of infrarenal and juxtarenal AAAs for patients with CRI, this study found a heightened mortality risk with supraceliac clamping and increased renal morbidity with suprarenal clamping, though these effects were not present for patients with normal renal function. Every effort should be made to keep the proximal clamp level as low as possible, especially in patients with CRI.

Renal Dysfunction Following Elective Endovascular Aortic Aneurysm Repair

Abdominal aortic aneurysm (AAA) is a degenerative disease of the aortic wall with potentially fatal complications. Open repair (OR) was considered the gold standard, until the emergence of endovascular aneurysm repair (EVAR), which is less invasive and equally (if not more) effective. As the popularity of endovascular procedures grows, related complications become more evident, with kidney damage being one of them. Although acute kidney injury (AKI) following EVAR is relatively common, its true incidence is still uncertain. Also, there is insufficient data concerning long-term renal outcomes after EVAR, especially with repeated contrast agent exposure. Despite the lack of firm evidence on the effectiveness of individual strategies, it is evident that prevention of AKI following EVAR requires a multifactorial approach. This review focuses on recent findings based on human studies regarding the current evidence of renal impairment after EVAR, its quantification and strategies for its prevention.

Contrast-Induced Kidney Nephropathy in Thoracic Endovascular Aortic Repair: A 2-Year Retrospective Study in 470 Patients

We identified changes in renal function in patients who underwent thoracic endovascular aortic repair (TEVAR) and the factors that may influence renal function. Information on 470 consecutive patients was collected. Kidney function and contrast volume were recorded. Unpaired t test, Spearman correlation, and logistic regression were used for statistical analysis. A Kaplan-Meier curve helped clarify our follow-up findings. Mean contrast volume was 90.5 ± 21.2 mL. The change in serum creatinine was significantly correlated with (1) preexisting renal pathology (P = .033) and (2) aortic dissection (AD) involving the renal arteries (P = .019). The change in serum urea nitrogen (ΔBUN) was only significantly correlated with AD involving the renal arteries (P = .0348). Contrast volume (P = .036, odds ratio = 1.010, 95% confidence interval: 1.001-1.019) was a risk factor for contrast-induced nephropathy (CIN) after TEVAR. Survival rates and renal failure rates among no CIN, CIN, and CIN-acute kidney injury groups at longest 27 months follow-up were significantly different. Creatinine and BUN were generally elevated post-TEVAR. Contrast-induced nephropathy post-TEVAR may correlate with renal comorbidities and renal artery involvement. Contrast volume is risk factor for CIN after TEVAR. More attention needs to be paid to patient renal function during follow-up.

Renal function after abdominal aortic aneurysm repair in patients with baseline chronic renal insufficiency: open vs. endovascular repair

BACKGROUND

The aim of this study is to analyze renal function impairment (RFI) after abdominal aortic aneurysm (AAA) repair in patients with preoperative chronic kidney disease (CKD).

METHODS

Retrospective cohort study of patients with CKD undergoing elective AAA repair between 2008-2015, dividing the sample into two groups: open repair (OR) and endovascular repair (EVAR). The primary outcome was RFI defined by the RIFLE scale, studying Risk (1.5-fold increase in Cr or GFR decline >25% compared to baseline) and kidney injury (doubling of Cr or GFR decline >50%).

RESULTS

Seventy-five patients (OR=29, EVAR=46). Baseline characteristics for OR and EVAR were similar except for age (70.4 vs. 77.2 years; P<0.001), coronary artery disease (31% vs. 56.5%; P=0.04), neck length (12.3 vs. 22.7 mm; P=0.001) and baseline GFR (40.6 vs. 36.9 mL/min; P=0.03). There were no inter-group differences in postoperative RFI: Risk of RFI 13.8% OR vs. 13% EVAR and kidney Injury 6.9% vs. 0% (P=0.19). There were also no differences in RFI at one year. Comparing GFR and Cr after surgery and at 12 months to baseline values, the OR group presented a significant postoperative decline in GFR compared to EVAR group (-3.8% vs. 11.1%; P=0.03), which had recovered at one-year follow-up (16.6% vs. 9.5%; P=0.43), while EVAR group presented with a tendency toward increased Cr during follow-up (-9.2% vs. 2.2%; P=0.08). Multivariate analysis did not identify independent RFI prognostic factors.

CONCLUSIONS

Both techniques can be used safely in patients with CKD and baseline CKD is not a limiting factor for either technique. RFI is rare and transient in both groups.

Patients with end-stage renal disease have poor outcomes after endovascular abdominal aortic aneurysm repair

OBJECTIVE

Although endovascular repair of abdominal aortic aneurysms (AAAs) has been demonstrated to have favorable outcomes, not all cohorts of patients with AAA fare equally well. Our goal was to investigate perioperative and 1-year outcomes in patients with end-stage renal disease (ESRD) on dialysis, who have traditionally fared worse after vascular interventions, to assess how ESRD affects outcomes in a large modern cohort of endovascular aneurysm repair (EVAR) patients.

METHODS

The Vascular Quality Initiative database was queried for all patients undergoing EVAR from 2010 to 2017. ESRD patients were compared with patients not on dialysis. Propensity-matched scoring and multivariable analysis were used to isolate the effects of ESRD.

RESULTS

Of 28,683 EVARs identified, there were 321 (1.12%) patients with ESRD on dialysis. Patients with ESRD had no difference in presenting AAA size (57.5 ± 12.7 mm vs 56.7 ± 17.2 mm; P = .44); however, they had more urgent/emergent repairs (20.6% vs 13.6%; P = .002) than those without ESRD. ESRD patients were more often younger, nonwhite, and nonobese and less likely to have commercial insurance (P < .05). ESRD patients more often had hypertension, coronary artery disease, congestive heart failure, previous lower extremity bypass, aneurysm repair, and carotid interventions (P < .05). There was no difference in the rate of concomitant procedures. Matching based on demographics, comorbidities, and operative details showed that ESRD patients had longer hospital length of stay (4.8 ± 9.4 days vs 4.1 ± 12.6 days; P = .026) and higher 30-day mortality (7% vs 2.4%; P < .001). There was no difference in cardiac, pulmonary, lower extremity, bowel, and stroke complications or return to the operating room. On multivariable analysis, ESRD was associated with 30-day mortality (odds ratio, 4.1; 95% confidence interval, 2.6-6.7; P < .001). Of the 24,750 elective EVARs, 1.04% had ESRD on dialysis. Matched data for elective EVAR show increased postoperative length of stay, hospital mortality, and 30-day mortality for ESRD patients on dialysis compared with those who are not. There was no association with postoperative myocardial infarction or pulmonary complications. At 1 year, patients with ESRD on dialysis had worse survival (78% vs 94%; P < .001), and ESRD was associated with higher mortality (hazard ratio, 3.3; 95% confidence interval, 2.5-4.2; P < .001).

CONCLUSIONS

Among patients undergoing EVAR, ESRD is independently associated with higher perioperative and 1-year mortality despite not being associated with higher postoperative complications. This should be taken into account during informed consent for EVAR and risk-benefit considerations in this high-risk population, particularly for elective repair.

Feasibility of three-dimensional fusion imaging with multimodality roadmap system during endovascular aortic repair

OBJECTIVE

Endovascular procedures for aortic aneurysm repair have become widely accepted as safe and effective surgical options. We investigated the efficacy of the multimodality roadmap (MMR) system with biplane fluoroscopy to attempt to reduce the use of contrast medium and exposure to radiation during surgery.

METHODS

We retrospectively reviewed 263 consecutive cases with elective endovascular aneurysm repair (EVAR) and thoracic endovascular aortic repair (TEVAR). Patients were categorized into two groups, with and without introduction of the MMR system, which was applied in 164 patients (62.4%). The MMR- group included 62 EVAR and 37 TEVAR cases, and the MMR+ group consisted of 81 EVAR and 83 TEVAR cases. Radiation dose, contrast medium use, and complications were compared between the MMR- and MMR+ groups in the respective EVAR and TEVAR groups.

RESULTS

There was a significantly lower amount of contrast medium use in the MMR+ group compared with the MMR- group in EVAR (32.9 ± 10.6 g and 28.2 ± 10.2 g; P = .009) and TEVAR (31.7 ± 11.5 g and 26.9 ± 7.8 g; P = .009). In addition, significantly lower radiation exposure was observed in the MMR+ group of TEVAR (872 ± 623 mGy vs 638 ± 463 mGy; P = .033). The operative time of the MMR+ group was significantly shorter for patients with TEVAR compared with the MMR- group (96.4 ± 27.0 minutes vs 86.2 ± 23.9 minutes; P = .023). The incidence of access injury and other complications was similar in both EVAR and TEVAR groups.

CONCLUSIONS

The MMR system with three-dimensional fusion imaging can reduce the contrast medium dose in EVAR and the exposure to contrast medium and radiation in TEVAR.

Open and endovascular aneurysm repair in the Society for Vascular Surgery Vascular Quality Initiative

The Society for Vascular Surgery Vascular Quality Initiative is a patient safety organization and a collection of procedure-based registries that can be utilized for quality improvement initiatives and clinical outcomes research. The Vascular Quality Initiative consists of voluntary participation by centers to collect data prospectively on all consecutive cases within specific registries which physicians and centers elect to participate. The data capture extends from preoperative demographics and risk factors (including indications for operation), through the perioperative period, to outcomes data at up to 1-year of follow-up. Additionally, longer-term follow-up can be achieved by matching with Medicare claims data, providing long-term longitudinal follow-up for a majority of patients within the Vascular Quality Initiative registries. We present the unique characteristics of the Vascular Quality Initiative registries and highlight important insights gained specific to open and endovascular abdominal aortic aneurysm repair.

Preoperative Evaluation of the Renal Function before the Treatment of Abdominal Aortic Aneurysms

BACKGROUND

Chronic impaired renal function constitutes a major risk factor of morbi-mortality during the treatment of an abdominal aortic aneurism (AAA). The inflammatory state due to the AAA could result in a reduction in the muscular mass and an overestimation of the glomerular filtration rate (GFR) with the usual formulas. The objective of this study was to determine if the formulas used to evaluate the estimated GFR were adapted in patients with AAA.

MATERIALS AND METHODS

Between August 2013 and November 2014, we conducted an exploratory study to evaluate the renal function before surgery for AAA in 28 patients. The renal function was evaluated by (1) the dosage of plasmatic creatinine, (2) the GFR estimated with the Cockroft-Gault, Modification of Diet in Renal Disease (MDRD), and chronic kidney disease epidemiology collaboration (CKD-EPI) formulas, (3) the creatinine clearance (CC), and (4) the direct measurement of the GFR with a reference method (iohexol clearance). Statistical analysis was carried out to compare and correlate the GFR estimated by the various formulas with the GFR measured by the reference technique.

RESULTS

The study included 21 men (75%) and 7 women (25%), with a median age of 76 years (58-89). The measured GFR was correlated with the GFR estimated from the CKD-EPI (rho = 0.78, P < 0.0001), the MDRD (rho = 0.78, P < 0.0001), the Cockroft-Gault (rho = 0.65, P = 0.0002), and CC (rho = 0.86, P < 0.0001). However, there were important individual variations between estimated and measured GFR. As regards the detection of the patients presenting a GFR <60 mL/min/1.73 m², the sensitivities of the CKD-EPI, MDRD, Cockroft-Gault formulas and CC were 64%, 64%, 71%, and 70%, respectively. Specificities were 71%, 79%, 57%, and 100%, respectively. The estimation of the GFR by the CKD-EPI formula had the lowest bias (-3.0). Bland-Altman plots indicated that the estimation of the GFR by the CKD-EPI formula had the best performance in comparison with the other methods.

CONCLUSIONS

This study found a statistical correlation between the measurement of the GFR and the various formulas available to estimation the GFR among AAA patients. The CKD-EPI formula is most appropriate. However, there were important individual variations between the measurement and the estimations of the GFR. A larger scale study is necessary to determine the profile of the patients with a risk of error in the estimation of the GFR. The French recommendations on the evaluation of the renal function before AAA treatment remain based on serum creatinine and should be revalued.

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.

[Endovascular versus conventional vascular surgery - old-fashioned thinking? Part 1: interventions on the aorta]

Endovascular therapy has widely replaced conventional open vascular surgical reconstruction. For this reason both techniques were widely considered to be competing approaches. Evidence-based data from randomized prospective trials, meta-analyses and clinical registries, however, demonstrated that both techniques should be used to complement each other. It became increasingly more evident that the use of either procedure depends on the underlying disease and the anatomical conditions, whereby a combination of both (hybrid approach) may be the preferred option in certain situations. This review focuses on the treatment of complicated acute type B aortic dissection, descending thoracic aortic aneurysms, thoracoabdominal aortic aneurysms as well as asymptomatic and ruptured abdominal aortic aneurysms.

Limited survival in dialysis patients undergoing intact abdominal aortic aneurysm repair

OBJECTIVE

Elective abdominal aortic aneurysm (AAA) repair in suitable candidates is a standard modality. The outcomes of AAA repair in patients with end-stage renal disease on dialysis are not well characterized, and there is questionable survival advantage in such patients with limited life expectancy. We sought to describe outcomes after AAA repair in U.S. dialysis patients.

METHODS

The United States Renal Data System was used to collect data on intact asymptomatic AAA repair procedures in dialysis patients in the United States between 2005 and 2008. Endovascular AAA repair (EVAR) and open aortic repair (OAR) were identified by Current Procedural Terminology codes. Primary outcomes were perioperative (30-day) mortality and long-term survival. Predictors of mortality were identified by multivariate regression models.

RESULTS

A total of 1557 patients were identified who had undergone elective AAA repair: 261 OAR and 1296 EVAR. The 30-day mortality was 11.3% (EVAR, 10.3%; OAR, 16.1%; P = .010), with increased age associated with increased mortality (odds ratio, 1.04; 95% confidence interval [CI], 1.02-1.07; P = .001). Kaplan-Meier survival estimates were 66.5% at 1 year (EVAR, 66.2%; OAR, 68%) and 37.4% at 3 years (EVAR, 36.8%; OAR, 40%; P = .33). Median survival was 25.3 months after EVAR and 27.4 months after OAR. Women had a higher mortality rate at 1 year (38.7%) compared with men (32.0%) (P = .015). There was no significant mortality difference at 1 year in comparing type of procedure in both men (EVAR, 31.6%; OAR, 34%; P = .55) and women (EVAR, 39.3%; OAR, 36%; P = .60). A Cox proportional hazards model demonstrated that male gender (hazard ratio [HR], 0.75; 95% CI, 0.62-0.92; P = .005), increased time on dialysis (HR for each year on dialysis, 0.79; 95% CI, 0.75-0.83; P < .001), kidney transplantation history (HR, 0.62; 95% CI, 0.43-0.88; P = .008), and diagnosis of hypertension (HR, 0.60; 95% CI, 0.48-0.75; P < .001) were protective against mortality. Increased age (HR, 1.02; 95% CI, 1.01-1.03; P < .001) and diabetes diagnosis (HR, 1.39; 95% CI, 1.13-1.71; P = .002) predicted increased mortality.

CONCLUSIONS

AAA patients on dialysis have high perioperative and 1-year mortality rates after EVAR or OAR, particularly diabetics, women, and the elderly. This raises questions about the indications for intact AAA repair in dialysis patients, in whom the size threshold may need to be raised. Dialysis patients may be best served by deferring repair of AAA until AAAs reach large size or become symptomatic, especially if OAR is required, given the higher perioperative mortality compared with EVAR.