Renal function changes after fenestrated endovascular aneurysm repair

Sex Related Differences in Perioperative Outcomes after Complex Endovascular Aortic Aneurysm Repair

BACKGROUND

Prior studies suggest female sex is associated with worse outcomes after complex endovascular aortic aneurysm repair (EVAR) due to anatomic differences. Therefore, we aimed to compare 30-day perioperative and long-term outcomes after complex EVAR by sex.

METHODS

A single-center retrospective review of consecutive elective and emergent complex EVAR with company-manufactured devices, laser fenestration, snorkel/periscope, or octopus technique was performed from 2012-2023. The primary outcome was a composite endpoint of any major adverse event (MAE), new-onset dialysis, or death within 30 days. Secondary 30-day technical and long-term outcomes were also assessed.

RESULTS

293 patients (57 females, 19%), mean age 74 years, underwent complex EVAR with commercially available Zenith fenestrated endovascular graft (71%), p-Branch (2%), laser fenestration (8%), snorkel/periscope (16%), or octopus (2%) techniques. Females had significantly different aneurysm-related anatomic characteristics compared to males, including smaller aneurysm diameters (58 ± 7.2 vs. 64 ± 13.2 mm, P < 0.001), more involved aneurysm extent (21.7% vs. 9.8% thoracoabdominal, P = 0.04), increased renal artery calcification (43.9% vs. 27.1%, P = 0.01), and smaller iliac (7.6 ± 1.3 vs. 8.9 ± 1.8 mm, P < 0.01). Operative outcomes were similar; however, females had a greater need for adjunctive access conduits (21.1% vs. 10.6%, P = 0.04), lower technical success (91.2% vs. 98.3%, P = 0.02), and longer median [interquartile range] length of stay (3.0 [4.0] vs. 2.0 [2.5] days, P < 0.001). The composite 30-day outcome of any MAE, new dialysis, or death was not significantly different (15.8% females vs. 11.4% males, P = 0.37). Technical endpoints including 30-day rates of target artery occlusion and type 1 or 3 endoleak were also similar between groups. At mean follow-up of nearly 3 years, females had significantly lower rate of renal function decline (16.0% vs. 41.9%, P < 0.001), but no differences were found in long-term all-cause mortality, aneurysm sac regression, reintervention, or total follow-up imaging studies between groups.

CONCLUSIONS

Females undergoing complex EVAR had challenging anatomy with higher intraoperative target artery occlusion, conduit use, and longer length of stay. However, 30-day and long-term outcomes were similar, suggesting females can undergo complex EVAR with high technical success and comparable perioperative outcomes to males. Females appeared to have protection from long-term renal function decline, which will be important for future study.

Preoperative proteinuria is independently associated with mortality after fenestrated endovascular aneurysm repair

OBJECTIVE

Fenestrated endovascular aneurysm repair (FEVAR) has become a mainstay in treating complex aortic aneurysms, though baseline patient factors predicting long-term outcomes remain poorly understood. Proteinuria is an early marker for chronic kidney disease and associated with adverse cardiovascular outcomes, but its utility in patients with aortic aneurysms is unknown. We aimed to determine whether preoperative proteinuria impacts long-term survival after FEVAR.

METHODS

A single-institution, retrospective review of all elective FEVAR was performed. Preoperative proteinuria was assessed by urinalysis: negative (0-29 mg/dL), 1+ (30-100 mg/dL), 2+ (101-299 mg/dL), and 3+ (≥300 mg/dL). The cohort was stratified by patients with proteinuria (≥30 mg/dL) vs those without (<30 mg/dL). Baseline, perioperative, and long-term outcomes were compared. The primary outcome, all-cause mortality, was evaluated by Kaplan-Meier analysis and independent predictors with Cox proportional hazards modeling.

RESULTS

Among 181 patients who underwent standard FEVAR from 2012 to 2022 (mean follow-up 33 months), any proteinuria was noted in 30 patients (16.6%). Patients with proteinuria were more likely to be Black (10.0% vs 1.3%) with a lower estimated glomerular filtration rate (eGFR) (52.7 ± 24.7 vs 67.7 ± 20.5 mL/min/1.73 m2), higher Society for Vascular Surgery comorbidity score (10.9 ± 4.3 vs 8.2 ± 4.7) and calcium channel blocker therapy (50.0% vs 29.1%), and larger maximal aneurysm diameter (67.2 ± 16.9 vs 59.8 ± 9.8 mm) (all P < .05). Thirty-day mortality was higher in the proteinuria group (10.0% vs 1.3%; P = .03). Overall survival at 1 and 5 years was significantly lower for those with proteinuria (71.5% vs 92.3% and 29.5% vs 68.1%; log-rank P < .001). On multivariable analysis, preoperative proteinuria was independently associated with over threefold higher hazard of mortality (hazard ratio [HR]: 3.21, 95% confidence interval [CI]: 1.66-6.20; P < .001), whereas preoperative eGFR was not predictive (HR: 0.99, 95% CI: 0.98-1.01; P = .28). Additional significant predictors included chronic obstructive pulmonary disease (HR: 2.04), older age (HR: 1.05), and larger maximal aneurysm diameter (HR: 1.03; all P < .05).

CONCLUSIONS

In our 10-year experience with FEVAR, preoperative proteinuria was observed in 17% of patients and was significantly associated with worse survival. In this cohort, proteinuria was independently associated with all-cause mortality, whereas eGFR was not, suggesting that urinalysis may provide an additional simple metric for risk-stratifying patients before FEVAR.

Impact of chronic kidney disease and end-stage renal disease on outcomes after complex endovascular and open aortic aneurysm repair

OBJECTIVE

Chronic kidney disease (CKD) and end-stage renal disease are traditionally associated with worse outcomes after endovascular aortic repair (EVAR) and open aneurysm repair (OAR) of abdominal aortic aneurysms (AAAs). However, there needs to be more data on complex AAA repair involving the aorta's visceral segment. This study stratifies complex AAA repair outcomes by CKD severity and dialysis dependence.

METHODS

All patients undergoing elective OAR and fenestrated/branched EVAR (F-BEVAR) for complex AAA 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: normal/mild (CKD 1 and 2), moderate (CKD class 3a), moderate to severe (CKD 3b), severe (CKD class 4 and 5), and dialysis. Only patients with clamp sites above one of the renal arteries were included for complex OAR. For F-BEVAR, patients with proximal landing zones below zone 5 (above celiac artery) were included, and distal landing zones between zones 1 and 5 were excluded. Primary outcomes were perioperative and 1-year mortality. Predictors of mortality were identified by Cox multivariate regression models.

RESULTS

We identified 7849 elective complex AAA repairs: 4230 (54%) complex OARs and 3619 (46%) F-BEVARs. Most patients were White (89%) and male (74%), with an average age of 72 ± 8 years. The patients who underwent F-BEVAR were older and had more comorbidities. Elective F-BEVAR for complex AAA started in 2012 and increased from 1.4% in 2012 to 58% in 2020 (P < .001). The OAR cohort had more perioperative complications, but less 1-year mortality. The normal/mild CKD cohort had the highest 1-year survival compared with other groups after both complex OAR and F-BEVAR. On Cox regression analysis, when compared with CKD 1-2, worsening CKD stage (CKD 3b: hazard ratio [HR], 2.5; 95% confidence interval [CI], 1.82-3.40; P < .001; CKD 4-5: HR, 1.9; 95% CI, 1.16-3.26; P = .011; and dialysis: HR, 4.4; 95% CI, 2.53-7.72; P < .001) were independently associated with 1-year survival after F-BEVAR. After complex OAR, worsening CKD stage but not dialysis was associated with 1-year mortality compared with CKD 1-2 (CKD 3b: HR, 1.6; 95% CI, 1.13-2.35; P = .009; CKD 4-5: HR, 3.4; 95% CI, 2.03-5.79; P < .001).

CONCLUSIONS

CKD severity is an essential predictor of perioperative and 1-year mortality after complex AAA repair, irrespective of the treatment modality, which may reflect the natural history of CKD. Consideration should be given to raising the threshold for elective AAA repair in patients with moderate to severe CKD and end-stage renal disease, given the high 1-year mortality rate.

Systematic review and meta-analysis of fenestrated or branched devices after previous open surgical aortic aneurysm repair

OBJECTIVE

Despite open surgical repair (OSR) of abdominal aortic aneurysms being considered as a durable solution, disease progression and para-anastomotic aneurysms may require further repair, and fenestrated and branched endovascular aneurysm repair (F/BEVAR) may be applied to address these pathologies. The aim of this systematic review was to assess technical success, mortality, and morbidity (acute kidney injury, spinal cord ischemia) at 30 days, and mortality and reintervention rates during the available follow-up, in patients managed with F/BEVAR after previous OSR.

METHODS

The PRISMA statement was followed, and the study was pre-registered to the PROSPERO (CRD42022363214). The English literature was searched, via Ovid, using MEDLINE, EMBASE, and CENTRAL databases, through November 30, 2022. Observational studies and case series with ≥5 patients (2000-2022), reporting on F/BEVAR outcomes after OSR, were considered eligible. The Newcastle-Ottawa Scale and GRADE were used to assess the risk of bias and quality of evidence. The primary outcome was technical success, mortality, and morbidity at 30 days. Data on the outcomes of interest were synthesized using proportional meta-analysis.

RESULTS

The initial search yielded 1694 articles. Eight retrospective studies (476 patients) were considered eligible. In 78.3% of cases, disease progression set the indication for reintervention. Technical success was estimated at 96% (95% confidence interval [CI], 89%-98%; I2 = 0%; 95% prediction interval [PI], 79%-99%). Thirty-day mortality was 2% (95% CI, 1%-9%; I2 = 0%; 95% PI, 0%-28%). The estimated spinal cord ischemia and acute kidney injury rates were 3% (95% CI, 1%-9%; I2 = 0%; 95% PI, 0%-30%) and 6% (95% CI, 2%-15%; I2 = 0%; 95% PI, 1%-40%), respectively. During follow-up, overall mortality was 5% (95% CI, 2%-12%; I2 = 34%; 95% PI, 0%-45%) and aorta-related mortality was 1% (95% CI, 0%-2%; I2 = 0%; 95% PI, 0%-3%). The rate of reinterventions was 16% (95% CI, 9%-26%; I2 = 22%; 95% PI, 3%-50%).

CONCLUSIONS

According to the available literature, F/BEVAR after OSR may be performed with high technical success and low mortality and morbidity during the perioperative period. Follow-up aortic-related mortality was 1%, whereas the reintervention rates were within the standard range following F/BEVAR.

Five-year outcomes of endosuture aneurysm repair in patients with short neck abdominal aortic aneurysm from the ANCHOR registry

OBJECTIVE

Hostile aortic neck anatomies such as proximal short necks are known to put patients at an increased risk for type IA endoleaks, migration, and need for reinterventions. The Heli-FX EndoAnchor System was designed to improve seal of aortic stent grafts. Endosuture aneurysm repair (ESAR) using EndoAnchors with the Endurant stent graft has been shown to be safe and effective for the treatment of patients with short necks through one year. This study reports the 5-year patient outcomes of the Aneurysm Treatment using the Heli-FX EndoAnchor System Global Registry (ANCHOR) short neck regulatory cohort.

METHODS

The 70 patients from the ANCHOR Registry were cohort submitted to regulators for approval of the Endurant short neck indication. Patients had an infrarenal neck length of ≥ 4 mm and <10 mm. At 5 years, this short neck cohort had clinical and imaging follow-up compliance rates of 85% (28/33) and 70% (23/33), respectively.

RESULTS

The short neck cohort had a mean age of 71.3±8.1 years and was 27.1% (19/70) female. Kaplan Meier freedom from all-cause mortality was 68.5 ± 6.2%, freedom from aneurysm-related mortality was 90.1 ± 4.5%, freedom from any endovascular or surgical secondary procedure was 76.9 ± 7.2%, and freedom from rupture was 95.6 ± 3.2%. Eight patients had a total of nine type IA endoleaks detected through 5 years, of which three resolved spontaneously by the next follow-up visit. There were two patients with renal complications who did not undergo reintervention and there were no device migrations reported through 5 years. After 5 years, 68.2% of patients (15/22) had sac regression, 13.6% (3/22) had stable sacs, and 18.2% (4/22) had increased sac diameter as compared with their 1-month measurements.

CONCLUSIONS

After ESAR treatment using Heli-FX EndoAnchors with Endurant, the 5-year outcomes of the short neck cohort from the ANCHOR registry had encouraging results with regards to proximal neck-related complications, secondary procedures, and sac regression. This review of ESAR in patients with short proximal necks showed positive outcomes through 5 years although follow-up of a larger cohort is necessary.

Association of Baseline Chronic Kidney Disease Stage With Short- and Long-Term Outcomes After Fenestrated Endovascular Aneurysm Repair

BACKGROUND

Fenestrated endovascular aneurysm repair (FEVAR) is a well-established treatment approach for juxtarenal and short-neck infrarenal aortic aneurysms. Recommendations and clinical outcomes are lacking for offering FEVAR in patients with chronic kidney disease (CKD). We aimed to compare short- and long-term outcomes for patients with none-to-mild versus moderate-to-severe CKD undergoing FEVAR.

METHODS

We retrospectively reviewed consecutive patients undergoing standard FEVAR with Cook devices at a single institution. The cohort was stratified by preoperative CKD stage none-to-mild or moderate-to-severe (CKD 1-2 and CKD 3-5, respectively). The primary outcome was postoperative acute kidney injury (AKI). Secondary outcomes included 30-day perioperative complications, 1- and 5-year rates of overall survival, dialysis, renal target artery patency, endoleak, and reintervention assessed by the Kaplan-Meier method. Aneurysm sac regression, number of surveillance computed tomography (CT) scans, and CKD stage progression were assessed at latest follow-up. Multivariate Cox proportional hazards modeling was used to evaluate the association of CKD stage 3 and stage 4-5 with all-cause mortality, controlling for differences in baseline characteristics.

RESULTS

From 2012- to 2022, 184 patients (of which 82% were male) underwent FEVAR with the Cook ZFEN device (mean follow-up 34.3 months). Group CKD 3-5 comprised 77 patients (42%), was older (75.2 vs. 73.0 years, P = 0.04), had increased preoperative creatinine (1.6 vs. 0.9 mg/dL, P < 0.01), and demonstrated increased renal artery ostial calcification (37.7% vs. 21.5%, P = 0.02) compared with Group CKD 1-2. Perioperatively, CKD 3-5 sustained higher estimated blood loss (342 vs. 228 ml, P = 0.01), longer operative times (186 vs. 162 min, P = 0.04), and longer length of stay (3 vs. 2 days, P < 0.01). Kaplan-Meier 1- and 5-year survival estimates were lower for CKD 3-5 (82.3% vs. 95.1%, P < 0.01 and 55.4% vs. 70.8%, P = 0.02). Fewer CKD 3-5 patients remained free from chronic dialysis at 1 year (94.4% vs. 100%, P = 0.015) and 5 years (84.7% vs. 100%, P < 0.01). There were no significant differences in postoperative AKI rate (CKD 1-2 6.5% vs. CKD 3-5 14.3%, P = 0.13), long-term renal artery patency, reinterventions, type I or III endoleak, mean sac regression, or total follow-up CT scans between groups. CKD stage progression occurred in 47 patients (31%) at latest follow-up but did not differ between stratified groups (P = 0.17). On multivariable modeling, age (hazard ratio 1.05, 95% confidence interval 1.01-1.09, P = 0.02) and CKD stage 4-5 (hazard ratio 6.39, 95% confidence interval 2.26-18.05, P < 0.01) were independently associated with mortality.

CONCLUSIONS

Preoperative CKD status did not negatively impact the durability or technical success related to aneurysm outcomes after FEVAR. Worsening CKD stage was associated with lower 1- and 5-year overall survival and freedom from dialysis after FEVAR with no statistically significant differences in 30-day or long-term technical aneurysm outcomes.

Spinal cord ischemia rates and prophylactic spinal drainage in patients treated with fenestrated/branched endovascular repair for thoracoabdominal aneurysms

OBJECTIVE

Spinal cord ischemia (SCI) is a devastating complication after thoracoabdominal aortic aneurysm (TAAA) repair. The benefit of prophylactic cerebrospinal fluid drainage (pCSFD) to prevent SCI is still under investigation. The aim of this study was to evaluate the SCI rate and the impact of pCSFD following complex endovascular repair (fenestrated or branched endovascular repair [F/BEVAR]) for type I to IV TAAA.

METHODS

The STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) statement was followed. A single-center retrospective study was conducted, including all consecutive patients, managed for TAAA type I to IV using F/BEVAR, between January 1, 2018, and November 1, 2022, for degenerative and post-dissection aneurysms. Patients with juxta- or pararenal aneurysms were excluded, as well as cases managed urgently for aortic rupture or acute dissection. After 2020, pCSFD in type I to III TAAAs was abandoned and replaced by therapeutic CSFD (tCSFD), performed only in patients presenting SCI. The primary outcome was the perioperative SCI rate for the entire cohort and the role of pCSFD for type I to III TAAAs.

RESULTS

In total, 198 patients were included (mean age, 71.1±3.4 years; 81.8% males), including 50.5% with type I to III TAAA. The primary technical success was 94.9%. The perioperative mortality was 2.5%. and the major adverse cardiovascular event (MACE) rate was 10.6%; 4.5% presented SCI of any type (2.5% paraplegia). When comparing the SCI group with the remaining cohort, patients with SCI presented higher MACE (66.7% vs 7.9%; P < .001) rate and longer intensive care unit stay (3.5 vs 1 day; P = .002). Following type I to III repair, similar SCI, paraplegia, and paraplegia with no recovery rates were reported in the pCSFD and tCSFD groups (7.3% vs 5.1%; P = .66; 4.8% vs 3.3%; P = .72; and 2% vs 0%; P = .37).

CONCLUSIONS

The incidence of SCI after TAAA I to IV endovascular repair was low. SCI was associated with significantly increased MACE and intensive care unit stay. The prophylactic use of CSFD in type I to III TAAAs was not associated with lower SCI rates and may not be justified routinely.

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.

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.

Postoperative management in patients with complex aortic aneurysms

Patients with complex aortic aneurysms (CAA) are often high risk due to advanced age and widespread atherosclerosis affecting numerous vascular territories. Therefore, a thorough perioperative evaluation is needed prior to performing in any type of aortic repair, regardless of whether an endovascular or open surgical approach is selected. Because these operations are technically demanding and often result in end organ ischemia, it is not surprising that complex aortic repair carries significant risk of morbidity and mortality. Disabling complications such as dialysis, major stroke and paraplegia constitute the main limitation of complex aortic repair. The aim of this article was to review postoperative management to mitigate complications after CAA repair.

Patient-specific computational modeling of endovascular aneurysm repair: State of the art and future directions

Endovascular aortic repair (EVAR) has become the preferred intervention option for aortic aneurysms and dissections. This is because EVAR is much less invasive than the alternative open surgery repair. While in-hospital mortality rates are smaller for EVAR than open repair (1%-2% vs. 3%-5%), the early benefits of EVAR are lost after 3 years due to larger rates of complications in the EVAR group. Clinicians follow instructions for use (IFU) when possible, but are left with personal experience on how to best proceed and what choices to make with respect to stent-graft (SG) model choice, sizing, procedural options, and their implications on long-term outcomes. Computational modeling of SG deployment in EVAR and tissue remodeling after intervention offers an alternative way of testing SG designs in silico, in a personalized way before intervention, to ultimately select the strategies leading to better outcomes. Further, computational modeling can be used in the optimal design of SGs in cases of complex geometries. In this review, we address some of the difficulties and successes associated with computational modeling of EVAR procedures. There is still work to be done in all areas of EVAR in silico modeling, including model validation, before models can be applied in the clinic, but much progress has already been made. Critical to clinical implementation are current efforts focusing on developing fast algorithms that can achieve (near) real-time solutions, as well as ways of dealing with inherent uncertainties related to patient aortic wall degradation on an individualized basis. We are optimistic that EVAR modeling in the clinic will soon become a reality to help clinicians optimize EVAR interventions and ultimately reduce EVAR-associated complications.

Long-term Outcomes after FEVAR for Juxtarenal Aortic Aneurysm

OBJECTIVE

Fenestrated endovascular aortic repair (FEVAR) for juxtarenal aortic aneurysm (jAAA) disease is safe and effective with good short- and mid-term outcomes. Durability issues focus mainly on proximal and distal seal as well as target vessel (TV) instability, and long-term data is scarce. In previous publications we have reported short-term outcomes after FEVAR while comparing early- and late-experience patient groups, as well as long-term results for the early cohort. In this series we provide long-term outcome in the late experience cohort treated with FEVAR in Vascular Center Malmö.

METHODS

Consecutive patients treated in Vascular Center Malmö with FEVAR for jAAA between 2007 and 2011 were included. Data was collected retrospectively from medical- and imaging records. Follow up consisted of a clinical examination 1 month post-operatively, and computed tomography angiography combined with plain abdominal X-ray at 1 and 12 months, and annually thereafter. Primary endpoints were TV instability, reinterventions and survival. Changes in aneurysm diameter and renal function as well as endoleaks were also analyzed.

RESULTS

94 patients were treated. Median follow-up time was 89 (range 0-152) months. 280 fenestrations or scallops were employed of which 205 were stented. Technical success was 89.4%. Primary TV patency was 94% ± 1 % at 1year, 90% ± 2% at 3 years and 89% ± 2% at 5 years. 37 (39.4%) patients needed a total of 70 reinterventions and mean time to first reintervention was 21 ± 3.97 months. 5 (5.3%) patients died of aneurysm related causes and overall survival was 95.7% ± 2.1% at 1 year, 87.1% ± 3.5% at 3 years and 71.0 ± 4.7% at 5 years. A stable or decreasing aortic diameter after treatment was seen in 91% of cases. Mean glomerular filtration rate (GFR) fell from 59.2 ± 14.9 ml/min/1.73m² pre-operatively to 50.0 ± 18.6 ml/min/1.73 m² at end of follow-up.

CONCLUSION

Long-term results after treatment of jAAA with FEVAR remain good and the treatment is safe and effective. Although the need for reintervention remains high, long-term renal function and survival support the use of FEVAR as a valid treatment option for jAAA disease.

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.

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.

First-in-Human Clinical Application of the Medyria TrackCath System in Endovascular Repair of Complex Aortic Aneurysms (ACCESS Trial): A Prospective Multicenter Single-Arm Clinical Trial

PURPOSE

The Medyria TrackCath Catheter (MedTCC) is an innovative, thermal convection-based blood flow velocity (BFV) tracking catheter that may be used during complex aortic endovascular procedures for identification and catheterization of target orifices. The ACCESS Trial analyzes the safety and performance of the MedTCC for targeted vessel catheterization to generally evaluate the feasibility of thermal convection-based BFV.

MATERIALS AND METHODS

We performed a first-in-human, proof-of-concept, prospective single-arm multicenter clinical trial between March 2018 and February 2019 in patients who underwent endovascular aortic procedures at 4 high-volume centers. During these procedures, the MedTCC was advanced over a guidewire through the femoral access. The D-shape was enfolded in the reno-visceral part of the aorta and target orifices were identified and catheterized with a guidewire via the side port of the MedTCC through BFV tracking. BFV measurements were performed at baseline (Baseline-BFV), alignment to the orifice (Orifice-BFV), and following catheterization (Confirmation-BFV) to prove correct identification and catheterization of target orifices. The procedural success rate, the catheterization success rate, procedure-related parameters, and (serious) adverse events ((S)AE) during the follow-up were analyzed.

RESULTS

A total of 38 patients were included in the safety group (SG) and 26 in the performance group (PG). The procedural success rate was 89% (PG), the MedTCC catheterization success rate was 98% (PG). The MedTCC reliably measured BFV changes indicated by significant differences in BFV between Baseline-BFV and Orifice-BFV (p<0.05). Median (interquartile range; IQR) fluoroscopy time per orifice was 5.0 (1.5-8.5) minutes [total surgery 49 (26-74) minutes], median (IQR) contrast agent used per orifice was 1.0 (0-5.0) mL [total surgery 80 (40-100) mL], and median (IQR) MedTCC-based procedural time was 3.0 (2.0-6.0) minutes. There was no device-related SAE.

CONCLUSIONS

The ACCESS Trial suggests that BFV measurement allows for reliable target orifice identification and catheterization. The use of MedTCC is safe and generates short fluoroscopy time and low contrast agent use, which in turn might facilitate complex endovascular procedures.

Incidence of Acute and Chronic Renal Failure Following Branched Endovascular Repair of Complex Aortic Aneurysms

BACKGROUND

The purpose of this study was to examine the incidence of acute kidney injury and chronic renal impairment following branched endovascular aneurysm repair (BEVAR) of complex thoracoabdominal aortic aneurysms (TAAA) using the Medtronic Valiant Thoracoabdominal Aortic Aneurysm stent graft system (MVM), the physician-modified Visceral Manifold, and Unitary Manifold stent graft systems. The objective was to report the acute and chronic renal function changes in patients following complex TAAA aneurysm repair.

METHODS

This is an analysis of 139 patients undergoing branched endovascular repair for complex TAAAs between 2012 and 2020. Patient renal function was evaluated using serum creatinine and estimated glomerular filtration rate at baseline, 48 hr, discharge, 1 month, 6 months, and annually to 2 years. Patients on dialysis prior to the procedure were excluded from data analysis.

RESULTS

A total of 139 patients (mean age 71.13; 64.7% male) treated for TAAA with BEVAR met inclusion criteria and were evaluated. A total of 530 visceral vessels were stented. A majority of patients (n = 131, 94.2%) underwent a single procedure while 8 required staged procedures. Thirty-day, 1-year and 2-year all-cause mortality rates were 5.8%, 25.2%, and 32.4%, respectively. Primary and secondary patency rates at a median follow-up of 26.9 months (95% CI; 21.1 - 32.7) were 96.2% and 97.5% for all vessels and 95.4% and 96.9% for renal arteries, respectively. Postoperative acute kidney injury (AKI) was identified in 22 (15.8%) patients. At discharge, 16 patients (11.6%) had an increase in CKD stage with 3 requiring permanent dialysis. Five additional patients required permanent dialysis over the 2-year follow-up period for a total of 8 (5.8%). Increasing age (HR = 1.0327, P= 0.0477), hemoglobin < 7 prior to procedure (HR = 2.4812, P= 0.0093), increasing maximum aortic diameter (HR = 1.0189, P= 0.0084), presence of AKI (HR = 2.0757, P= 0.0182), and increase in CKD stage (HR = 1.3520, P= 0.002) at discharge were significantly associated with decreased patient survival.

CONCLUSIONS

Postoperative AKI and a chronic decline in renal function continue to be problematic in endovascular repair of complex aortic aneurysms. This study found that BEVAR using the manifold configuration resulted in immediate and mid-term renal function that is comparable to similar analyses of branched and/or fenestrated grafts.

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.

Patient-specific computational flow modelling for assessing hemodynamic changes following fenestrated endovascular aneurysm repair

Objective

This study aimed to develop an accessible patient-specific computational flow modelling pipeline for evaluating the hemodynamic performance of fenestrated endovascular aneurysm repair (fEVAR), with the hypothesis that computational flow modelling can detect aortic branch hemodynamic changes associated with fEVAR graft implantation.

Methods

Patients who underwent fEVAR for juxtarenal aortic aneurysms with the Cook ZFEN were retrospectively selected. Using open-source SimVascular software, preoperative and postoperative visceral aortic anatomy was manually segmented from computed tomography angiograms. Three-dimensional geometric models were then discretized into tetrahedral finite element meshes. Patient-specific pulsatile in-flow conditions were derived from known supraceliac aortic flow waveforms and adjusted for patient body surface area, average resting heart rate, and blood pressure. Outlet boundary conditions consisted of three-element Windkessel models approximated from physiologic flow splits. Rigid wall flow simulations were then performed on preoperative and postoperative models with the same inflow and outflow conditions. We used SimVascular's incompressible Navier-Stokes solver to perform blood flow simulations on a cluster using 72 cores.

Results

Preoperative and postoperative flow simulations were performed for 10 patients undergoing fEVAR with a total of 30 target vessels (20 renal stents, 10 mesenteric scallops). Postoperative models required a higher mean number of mesh elements to reach mesh convergence (3.2 ± 1.8 × 10⁶ vs 2.6 ± 1.1 × 10⁶; P = .005) with a longer mean computational time (10.3 ± 6.3 hours vs 7.8 ± 3.5 hours; P = .04) compared with preoperative models. fEVAR was associated with small but statistically significant increases in mean peak proximal aortic arterial pressure (140.3 ± 11.0 mm Hg vs 136.9 ± 8.7 mm Hg; P = .02) and peak renal artery pressure (131.6 ± 14.8 mm Hg vs 128.9 ± 11.8 mm Hg; P = .04) compared with preoperative simulations. No differences were observed in peak pressure in the celiac, superior mesenteric, or distal aortic arteries (P = .17-.96). When measuring blood flow, the only observed difference was an increase in peak renal flow rate after fEVAR (17.5 ± 3.8 mL/s vs 16.9 ± 3.5 mL/s; P = .04). fEVAR was not associated with changes in the mean pressure or the mean flow rate in the celiac, superior mesenteric, or renal arteries (P = .06-.98). Stenting of the renal arteries did not induce significant changes time-averaged wall shear stress in the proximal renal artery (23.4 ± 8.1 dynes/cm² vs 23.2 ± 8.4 dynes/cm²; P = .98) or distal renal artery (32.7 ± 13.9 dynes/cm² vs 29.6 ± 11.8 dynes/cm²; P = .23). In addition, computational visualization of cross-sectional velocity profiles revealed low flow disturbances associated with protrusion of renal graft fabric into the aortic lumen.

Conclusions

In a pilot study involving a selective cohort of patients who underwent uncomplicated fEVAR, patient-specific flow modelling was a feasible method for assessing the hemodynamic performance of various two-vessel fenestrated device configurations and revealed subtle differences in computationally derived peak branch pressure and blood flow rates. Structural changes in aortic flow geometry after fEVAR do not seem to affect computationally estimated renovisceral branch perfusion or wall shear stress adversely. Additional studies with invasive angiography or phase contrast magnetic resonance imaging are required to clinically validate these findings. (JVS–Vascular Science 2021;2:53-69.)

Clinical Relevance

Using a computational flow modelling for assessing the hemodynamic performance of fenestrated endovascular aneurysm repair (fEVAR), this real-world, patient-specific study included 10 participants and found that structural changes in aortic flow geometry after fEVAR did not seem to adversely impact estimated renal or visceral branch perfusion metrics (eg, peak and mean arterial pressure and flow rates) or wall shear stress. These findings overall support the ongoing clinical use of commercially available fEVAR devices for repair of juxtarenal aortic aneurysms, and provides a computational framework for future evaluation of fEVAR configurations in a preoperative or postoperative settings.

Parallel Grafting Should Be Considered as a Viable Alternative to Open Repair in High-Risk Patients With Paravisceral Aortic Aneurysms

BACKGROUND

Parallel grafting presents a viable method for treating patients with complex aortic aneurysms. The current literature is limited to mostly pararenal configurations. We examined our results in patients with SMA and/or Celiac artery involvement.

METHODS

A retrospective analysis was performed for all patients undergoing parallel grafting during the period of 2014 to 2018 at a single institution. All patients had at least SMA with and/or without Celiac artery parallel grafting.

RESULTS

Seventy-nine patients (65% male, median age 74) were treated with 208 parallel grafts. Median ASA score is 4. Forty-nine cases were elective, 22 urgent, and 8 emergent. Mean pre-operative aneurysm diameter was 7.1 cm (4.6-15 cm). Self-expanding covered stents were used for the renal arteries (mean 6.3mm), and balloon-expandable covered stents were used for the SMA and Celiac (mean SMA 8.6 mm, mean celiac 8.3 mm). Axillary exposure was the choice of access in 68 patients (86%). Technical success was achieved in all cases. We defined this as aneurysm sac exclusion with patent visceral stent grafts, and absent to mild gutter leaks. Mean aortic graft proximal seal achieved was 48mm. Coverage extended above the celiac artery in 75% (10% stented and 65% covered). Median contrast volume was 145ml, operative duration was 4 hours, fluoroscopy time was 56 min, and EBL was 250 ml. Perioperative mortality was 6.1%. 4.5%, and 25%, for the elective, urgent, and emergent groups, respectively. There was no incidence of spinal cord ischemia. Axillary access was complicated in 4 patients, requiring patch closure of the axillary artery. One patient developed postprocedural ESRD from a rupture and ATN despite patent renal stents. Of those patients with a patent GDA and celiac coverage, 2 required a cholecystectomy. Nine patients had a persistent gutter leak at the conclusion of the procedure. Median follow-up was 12 months. On follow-up imaging, all SMA and Celiac stents were patent. Six renal stents were occluded and 2 patients progressed to ESRD, both solitary renal periscope configurations at the index procedure. Only 4 patients had persistent gutter leaks with 2 requiring reintervention. Ninety-five percent of patients demonstrated sac regression or stabilization with a mean sac size of 6.5 cm.

CONCLUSIONS

Parallel grafting presents a safe, efficacious and off the shelf alternative to conventional repair of complex aortic aneurysms involving the visceral aorta.

Respiratory-induced changes in renovisceral branch vessel morphology after fenestrated thoracoabdominal aneurysm repair with the BeGraft balloon-expandable covered stent

OBJECTIVE

We evaluated the respiratory-induced changes in branch vessel geometry after thoracoabdominal fenestrated endovascular aneurysm repair (fEVAR) with the Bentley BeGraft graft (Innomed GmbH, Hechingen, Germany) as the covered bridging stent.

METHODS

Patients treated with fEVAR for thoracoabdominal aortic aneurysms with a custom-made Zenith fenestrated endograft (Cook Medical Europe Ltd, Limerick, Ireland) and Bentley BeGraft peripheral stents were prospectively recruited. Using SimVascular software (Open-Source Medical Software Corp, San Diego, CA), the pre- and postoperative aortic and branch contours were segmented from computed tomography angiograms performed during inspiratory and expiratory breath-holds. The centerlines were extracted from the lumen contours, from which the branch take-off angles, distal stent angles, and peak branch curvature changes were computed. Paired, two-tailed t tests were performed to compare the pre- and postoperative deformations.

RESULTS

Renovisceral vessel geometry was evaluated in 12 patients undergoing fEVAR with a total of 46 target vessels (10 celiac arteries, 12 superior mesenteric arteries [SMAs], 24 renal arteries). Implantation of BeGraft bridging stents was associated with a significant reduction in respiration-induced changes in vessel branch angulation (Δ5.3° ± 3.9° vs Δ12.0° ± 8.3° [postoperative vs preoperative]; P = .001) and mean curvature (0.72 ± 0.22 cm^-1 vs 0.53 ± 0.18 cm^-1) in the renal arteries, without significant changes in the celiac arteries or SMAs. No significant difference was found in end-stent angle motion in the renal arteries (P = .77), celiac arteries (P = .34), or SMAs (P = .55). The maximum local vessel curvature change decreased after fEVAR in the SMAs (Δ0.28 cm^-1 vs Δ0.47 cm^-1; P = .04) but was unchanged in the celiac (P = .61) and renal (P = .51) arteries.

CONCLUSIONS

Implantation of the BeGraft as a bridging stent in fEVAR was associated with decreased respiratory-induced deformation in the renal branch take-off angulation and mean renal artery curvature, with reduced maximum curvature bending in the SMA compared with the preoperative anatomy. However, the BeGraft allowed for celiac and renal artery bending similar to that in the native preoperative state. These findings suggest that the use of BeGraft peripheral stents with fEVAR will closely mimic the native arterial branch geometry and vessel conformability caused by relatively aggressive respiratory motion.

Effect of renal function on patient survival after endovascular thoracoabdominal and pararenal aortic aneurysm repair

BACKGROUND

Renal dysfunction can be a prohibitive risk for open repair of complex thoracoabdominal aortic aneurysms (TAAAs) and pararenal aortic aneurysms (PRAAs). However, the effect of renal dysfunction from fenestrated and branched endovascular aneurysm repair (FB-EVAR) on outcomes is poorly defined. Our objective was to review the association of renal function on patient survival after FB-EVAR.

METHODS

The present study reviewed the clinical data of consecutive patients enrolled in a prospective nonrandomized study to investigate FB-EVAR for PRAAs and TAAAs at a single institution with 1 year of follow-up (2013-2017). The patients were categorized by preoperative chronic kidney disease (CKD) classification, and the early- and long-term mortality was assessed.

RESULTS

During the study period, 231 patients had undergone FB-EVAR for 80 PRAAs, 89 type I-III TAAAs, and 62 type IV TAAAs. The mean age was 74.6 ± 6.7 years, and 71% were men. Of the 231 patients, 126 had had CKD stage 1-2, 96 CKD stage 3, and 9 CKD stage 4-5 (all with baseline creatinine >2.0 mg/dL). Patients with CKD stage 4-5 had demographic data similar to those with normal renal function but had had slightly larger aneurysms (6.5 vs 7 cm; P = .15). The 30-day mortality was 0.5% (n = 1) for those with CKD 1-3 vs 0% for those with CKD 4-5 (P = .73). The 1- and 3-year survival analysis showed no major hazards (95% vs 88% and 84% vs 75%, respectively; log-rank P = .98) between the CKD 1-3 and CKD 4-5 groups. The median follow-up period was 2.6 years (interquartile range, 1.5-3.7 years). Two patients with CKD 4-5 had died during the follow-up period.

CONCLUSIONS

Although a small sample size for evaluation, selected patients with CKD 4-5 might have similar short- and long-term mortality compared with those with normal to moderate renal dysfunction after FB-EVAR. Although a major contraindication for open repair, renal dysfunction might not be as prohibitive for endovascular repair in well-selected patients.

Renal Stent Complications and Impact on Renal Function after Standard Fenestrated Endovascular Aneurysm Repair

BACKGROUND

To report renal outcomes including long-term patency, secondary interventions, and related renal function after fenestrated endovascular aortic repair (fEVAR).

METHODS

Single-center retrospective review of patients undergoing fEVAR between 2012 and 2018 using the Cook ZFEN device. Renal stent complications, defined as any stenosis, occlusion, kink, renal stent-related endoleak, and reinterventions were tabulated. Estimated glomerular filtration rate (eGFR) was estimated using the Modification of Diet in Renal Disease formula.

RESULTS

During the study period, 114 patients underwent elective fEVAR. Of 329 total target vessels, 193 renal arteries were stented (133 Atrium iCAST, 60 Gore VBX). Technical success was achieved in 97.4%, and the mean follow-up was 23.3 months. Seventeen renal complications occurred in 14 patients (12.3%), including 4 occlusions, 9 stenosis, 3 dislocations, and 1 type III endoleak. All stent complications underwent endovascular reintervention with a median hospital stay of 1 day (0-10) and a technical success of 94.2%. One patient suffered renal hemorrhage that warranted embolization. Patients with occlusion were treated the day of diagnosis, and mean time from diagnosis to intervention for stenosis was 21.5 days. Estimated primary patency was 92.1 % and 81.5% at 24 and 48 months, respectively. On multivariate analysis, larger native renal artery diameter was the only independent protective factor against patency loss (HR 0.23 (0.09-0.59)). Secondary patency at latest follow-up was 99.4%. Mean eGFR was not significantly different at latest follow-up between patients with renal complications versus those without (43.75 vs. 55.58 mL/min/1.73 m², P = 0.09). Comparing patients with and without renal stent complications, 81.4% and 72.7% of patients had stable or improved renal disease by chronic kidney disease staging compared with baseline (P = 0.51).

CONCLUSIONS

fEVAR is a durable option for the treatment of juxtarenal aortic aneurysms and is associated with excellent secondary patency. Renal stent complications have no significant impact on renal function, but smaller native renal arteries are at higher risk of stent-graft complications.

Renal Artery Outcomes After Open Repair of Suprarenal or Type IV Thoraco-abdominal Aortic Aneurysms

OBJECTIVE

The aim of this study was to evaluate the mid and long term patency of elective renal artery reconstructions during open surgical repair of suprarenal aortic aneurysms (SRAA) and type 4 thoraco-abdominal aortic aneurysms (T4AAA).

METHODS

This retrospective, single centre study included all consecutive patients who underwent surgery for SRAA or T4AAA between January 2009 and December 2019 at Toulouse University Hospital. All patients underwent strict pre-operative planning with computed tomography angiography (CTA) and 3D reconstruction of the aortic aneurysm, visceral and renal artery anatomy to choose the most appropriate surgical technique for each case. Primary patency, primary assisted patency, and rates of re-intervention were calculated using the Kaplan-Meier method.

RESULTS

In total, 103 patients, having undergone 159 renal artery revascularisation procedures, were enrolled in the study. Fifty-five patients presented with a type T4AAA and 48 patients with a SRAA. In hospital mortality was 2.9%. In association with aortic surgery, 100 direct re-implantation (62.8%), 48 retrograde bypasses (30.1%), and 11 anterograde bypasses (6.9%) of the renal arteries were performed. Median follow up was 45.9 ± 36 months. Renal artery primary patency rates were 99.4%, 96.4%, and 93.1% at one, three, and five years, respectively. Assisted primary patency rates were 99.4%, 97.7%, and 97.7% at one, three, and five years, respectively, with five cases of renal stenosis > 70% successfully treated by renal stenting. No significant difference in patency was found regarding the type of renal revascularisation.

CONCLUSION

This retrospective study suggests that the mid term patency of elective open renal artery reconstruction during SRAA and type T4AAA surgery preceded by pre-operative planning with 3D-CTA reconstruction, yields excellent outcomes whatever the technique used.

Fenestrated-branched endovascular aortic repair in patients with chronic kidney disease

OBJECTIVE

Renal function impairment is a common complication after open repair of complex abdominal aortic aneurysms and thoracoabdominal aortic aneurysms (TAAAs). The purpose of this study was to assess renal perioperative outcomes and renal function deterioration after fenestrated-branched endovascular aneurysm repair (F/BEVAR) in patients with chronic kidney disease (CKD).

METHODS

The study included 186 patients who underwent F/BEVAR between 2013 and 2018 for suprarenal, juxtarenal, and type I to type IV TAAAs. Glomerular filtration rate (GFR) was calculated using the Modification of Diet in Renal Disease (MDRD) study equation. Postoperative acute kidney injury (AKI) and CKD were defined using RIFLE criteria (Risk, Injury, Failure, Loss, and End-stage renal disease) and CKD staging system (stage ≥3, GFR <60 mL/min/1.73 m²), respectively. For those without baseline CKD, renal decline was defined as a drop in GFR <60 mL/min/1.73 m² (ie, progression to CKD stage 3 or higher). For patients with baseline renal dysfunction, GFR decline ≥20% or progression in CKD stage (ie, from stage 3 to stage 4) was considered renal decline.

RESULTS

CKD was present in 83 patients (44.6%). Postoperative AKI was diagnosed in 27 patients (14.5%); 13 (48.1%) had history of CKD and 14 (51.9%) had adequate renal function preoperatively (P = .8). None of these patients required permanent renal replacement therapy. Intraoperative technical success was 100%. Overall 30-day mortality was 1.1%. There was no difference in 30-day mortality in patients with (1.2%) and without (1.0%) CKD (P = .5). During a median follow-up time of 12 months (interquartile range, 6-23 months), renal decline was observed in 21 patients (25.3%) with previous CKD and in 11 patients (10.6%) without CKD (P = .01). Among patients with previous CKD, 18 patients (9%) progressed from stage 3 CKD to stage 4. In patients with progression in CKD stage, two (5%) had renal stent stenosis requiring restenting. Among patients with renal decline, 13 had juxtarenal aneurysms (21.3%), 27 had suprarenal aneurysms (44.3%), and 21 had TAAAs (34.3%; P = .4). Subset analysis of patients who developed AKI in the immediate postoperative period found that patients with a history of CKD were less likely to experience freedom from renal decline.

CONCLUSIONS

F/BEVAR is an effective and safe procedure for patients with complex abdominal aortic aneurysms and TAAAs, even among patients with CKD. The frequency of AKI was not affected by pre-existing CKD. Midterm outcomes demonstrated that progression of CKD was more frequent among patients with pre-existing CKD, but permanent renal replacement therapy was not required. Anatomic extent of aneurysms did not affect CKD progression. CKD patients are susceptible to renal decline over time if they experience AKI in the postoperative period. Therefore, preventing AKI in the postoperative period should be regarded as a priority. Long-term effects of CKD after F/BEVAR remain to be elucidated.

Acute Kidney Injury after Complex Endovascular Aneurysm Repair

Background:

Complex endovascular repair of abdominal aortic aneurysm carries higher perioperative morbidity than standard infrarenal endovascular repair.

Objective:

This study reviews the incidence and associated factors of acute kidney injury in complex aortic endovascular repair of juxtarenal, pararenal, and thoracoabdominal aortic aneurysms.

Methods:

A literature review was performed for all studies on the endovascular repair of juxtarenal, pararenal, and thoracoabdominal aneurysms that evaluated rates of acute kidney injury as an outcome. Outcomes were further analyzed by the level of anatomic complexity and method of repair.

Results:

52 studies met inclusion criteria, with a total of 5454 individuals undergoing repair from 2004 to 2017. The overall rate of acute kidney injury ranged widely from 0 to 41%, with a rate of hemodialysis from 0 to 19% (temporary) and 0 to 14% (permanent). Increasing anatomic complexity was associated with higher rates of acute kidney injury. Mode of endovascular repair, learning curve effect, and preoperative chronic renal insufficiency did not demonstrate any associations with the outcome.

Conclusion:

Published rates of acute kidney injury in complex aortic aneurysm repair vary widely with few definitively associated factors other than increasing anatomic complexity and operative time. Further study is needed for the identification of predictors related to postoperative acute kidney injury.

Duplex ultrasound surveillance of renal branch grafts after fenestrated endovascular aneurysm repair

OBJECTIVE

The use of duplex ultrasound (DUS) examinations for surveillance after fenestrated endovascular aneurysm repair (FEVAR) is not well-studied. Our objective was to further characterize normal and abnormal duplex findings in renal branch grafts after FEVAR.

METHODS

We retrospectively reviewed a single-center experience involving consecutive patients treated with Cook ZFEN devices between 2012 and 2017. Postoperative imaging consisted of a computed tomography (CT) scan at 1 month, 6 months, 1 year, and annually thereafter. As experienced progressed, DUS examination with or without concurrent CT scans were obtained in a nonstandardized protocol, particularly for patients with decreased renal function. Renal patency loss was defined as occlusion or stenosis of greater than 50% evaluated on 3-day renal artery center-line imaging.

RESULTS

A total of 116 patients were treated with FEVAR, of which 60 (51.7%) had concurrent CT and renal DUS images available for review. Six patients (10%) had limited ultrasound studies owing to bowel gas and were excluded. The study cohort therefore included 54 patients receiving of 94 renal fenestrated stents with a mean follow-up of 23 months. Twelve cases of renal patency loss in 10 patients (9 stenoses, 3 occlusions) were found on CT scanning, 11 (91.6%) of which had concurrent abnormalities found on ultrasound examination. Stents with compression at the junction of the main body exhibited significantly elevated mean Peak systolic velocities (PSV) compared with nonstenosed stents (349.2 cm/s vs 115.3 cm/s; P = .003). Stenosis in the most proximal portion of the stent (ie, within the main body) showed no difference in proximal PSV (86.0 cm/s vs 131.9 cm/s; P = .257); however, dampened PSV showed significant differences in the mid (17.5 cm/s vs 109.9 cm/s; P = .027) and distal (19.0 cm/s vs 78.3 cm/s; P = .028) segments compared with nonstenosed stents. All occluded stents demonstrated no flow detection. Proximal PSV served as a strong classifier for junctional stenosis (area under the curve, 0.98). A combined criterion of proximal PSV of greater than 215 cm/s or distal PSV of less than 25 cm/s resulted in a sensitivity of 91.6% and specificity of 85.3% for detecting patency loss. All stents that were compromised underwent successful secondary reintervention and restoration of patency.

CONCLUSIONS

DUS imaging is a clinically useful modality for surveillance of renal branch grafts after FEVAR. Patterns of segmental velocity elevation (proximal PSV, >215 cm/s) and dampening in the distal renal indicate potential hemodynamic compromise and should prompt more aggressive workup or imaging and likely be considered for secondary intervention.

Impact of Renal Artery Stent-Graft Placement on Renal Function in Chronic Aortic Dissection

PURPOSE

To evaluate the effect of renal stent-graft placement on kidney function and size alternation in chronic aortic dissection.

MATERIALS AND METHODS

Twenty-five consecutive patients with chronic aortic dissection after thoracic endovascular aortic repair who underwent renal stent-graft placement between January 2015 and December 2016 were retrospectively reviewed. Forty-three patients with chronic aortic dissection who received thoracic endovascular aortic repair in the same period were reviewed as a control group for kidney volume comparison.

RESULTS

Twenty-five stent-grafts were deployed over 25 renal arteries. Overall renal function was assessed by the slope of the regression line constructed from the plots of creatinine clearance versus time within 2 years after the procedure (-0.2810 vs -0.3146 mL/min^-1/mo^-1, P = .868), kidney volume at 12 months (129.4 ± 40.9 vs 137.0 ± 44.2 cm², P = .193) and effective renal plasma flow at 6 months (106.3 ± 46.9 vs 124.4 ± 55.5 mL/min, P = .050) and was not significantly deteriorated. Seven treated patients (87.5%) with a renal artery supplied by a false lumen had a decrease in kidney volume, as did 14 patients (56%) in the control group (P = .206). Three patients with a dissected renal artery (75%) in the stent-graft group had an increase in kidney volume compared with 1 patient (11.1%) in the control group (P = .052).

CONCLUSIONS

Occlusion of the re-entry tear by a stent-graft in the renal artery remains a safe strategy to promote false lumen thrombosis. The stent-graft poses a potential risk of reducing the kidney volume in kidneys supplied by the false lumen but may provide a positive effect in kidney volume with a concomitant dissected renal artery in chronic aortic dissection.

Impact of aortic wall thrombus on late changes in renal function among patients treated by fenestrated-branched endografts

OBJECTIVE

Renal function deterioration is an important determinant of mortality in patients treated for complex aortic aneurysms. We have previously determined that catheter and guidewire manipulation in diseased aortas during fenestrated-branched endovascular aneurysm repair (F-BEVAR) is associated with risk of renal function deterioration. The aim of this study was to describe the impact of atherothrombotic aortic wall thrombus (AWT) on renal function deterioration among patients treated by F-BEVAR for pararenal and extent IV thoracoabdominal aortic aneurysms.

METHODS

Clinical data of 212 patients treated for complex aortic aneurysms with F-BEVAR were entered into a prospectively maintained database (2007-2015). AWT was evaluated by computed tomography angiography using volumetric measurements in nonaneurysmal aortic segments. AWT was classified as mild, moderate, or severe using objective assessment of the number of affected segments, thrombus type, thickness, area, and circumference. Acute kidney injury (AKI) was defined using Risk, Injury, Failure, Loss of kidney function, and End-stage renal disease (RIFLE) criteria, and renal function deterioration was defined by a decline in estimated glomerular filtration rate (eGFR) >30% from baseline. Patient survival and renal outcomes were assessed at dismissal, at 6 to 8 weeks, at 6 months, and annually, including AKI, serum creatinine concentration, eGFR, chronic kidney disease stage, need for renal replacement therapy, and presence of kidney infarction.

RESULTS

There were 169 male (80%) and 43 female (20%) patients with a mean age of 75 ± 7 years. Aneurysm extent was pararenal in 157 patients and extent IV thoracoabdominal aortic aneurysm in 55 patients. A total of 700 renal-mesenteric arteries were incorporated (3.1 ± 1 vessels/patient). AWT was classified as mild in 98 patients (46%), moderate in 75 (35%), and severe in 39 (19%). At 30 days, 45 patients (21%) developed AKI. Decline in eGFR and kidney infarction were associated with higher AWT volume index and severe AWT classification (P < .05). There was no association of AWT with 30-day mortality, which was 0.5% for the entire cohort. Mean follow-up was 29 ± 23 months. Freedom from renal function deterioration was 73% ± 6% for mild, 81% ± 6% for moderate, and 66% ± 8% for severe AWT patients at 3 years (P = .012) and 46% ± 9% and 82% ± 4% for those with or without AKI after the initial procedure (P < .001). Overall, 41 patients (19%) had progression of chronic kidney disease stage, but none of the patients required renal replacement therapy. Survival was 73% ± 5% for mild, 72% ± 6% for moderate, and 69% ± 10% for severe AWT patients at 3 years (P = .67).

CONCLUSIONS

AWT is a significant predictor of AKI and continued decline in renal function after the initial F-BEVAR procedure. Longer follow-up time is needed to determine the actual impact of AWT on survival.

Assessment of aortic wall thrombus predicts outcomes of endovascular repair of complex aortic aneurysms using fenestrated and branched endografts

OBJECTIVE

The goal of this study was to investigate the correlation between atherothrombotic aortic wall thrombus (AWT) and clinical outcomes in patients treated by fenestrated-branched endovascular aortic repair (F-BEVAR) and present a new classification system for assessment of AWT burden.

METHODS

The clinical data of 301 patients treated for pararenal and thoracoabdominal aortic aneurysms (TAAAs) by F-BEVAR was reviewed. The study excluded 89 patients with extent I to III TAAA because of extensive laminated thrombus within the aneurysm sac. Computed tomography angiograms were analyzed in all patients to determine the location, extent, and severity of atherothrombotic AWT. The aorta was divided into three segments: ascending and arch (A), thoracic (B) and renal-mesenteric (C). Volumetric measurements (cm³) of AWT were performed using TeraRecon software (TeraRecon Inc, Foster City, Calif). These volumes were used to create an AWT index by dividing the AWT volume from the total aortic volume. A classification system was proposed using objective assessment of the number of affected segments, thrombus type, thickness, area, and circumference. Clinical outcomes included 30-day mortality, neurologic and gastrointestinal complications, renal events (Risk, Injury, Failure, Loss of kidney function, End-stage renal disease [RIFLE]), and solid organ infarction.

RESULTS

The study included 212 patients, 169 men (80%) and 43 women (20%), with a mean age of 76 ± 7 years. A total of 700 renal-mesenteric arteries were incorporated (3.1 ± 1 vessels/patient). AWT was classified as mild in 98 patients (46%) and was considered moderate or severe in 114 (54%). There was one death (0.5%) at 30 days. Solid organ infarction was present in 50 patients (24%), and acute kidney injury occurred in 45 patients (21%) by RIFLE criteria. An association with higher AWT indices was found for time to resume enteral diet (P = .0004) and decline in renal function (P = .0003). Patients with acute kidney injury 2 by RIFLE criterion had significantly higher (P = .002) AWT index scores in segment B. Spinal cord injury occurred in three patients (1.4%) and stroke in four (1.9%), but were not associated with the AWT index. Severity of AWT using the new proposed classification system correlated with the AWT index in all three segments (P < .001). Any of the end points occurred in 35% of the patients with mild and in 53% of those with moderate or severe AWT (P = .016).

CONCLUSIONS

AWT predicts solid organ infarction, renal function deterioration, and longer time to resume enteral diet after F-BEVAR of pararenal and type IV TAAAs. Evaluation of AWT should be part of preoperative planning and decision making for selection of the ideal method of treatment in these patients.

Fenestrated and Branched Stent Grafting in Complex Aneurysmatic Aortic Disease: A Single-Center Early Experience

BACKGROUND

The aim of this study is to present our early experience and highlight the technical difficulties associated with the use of fenestrated and branched stent grafts to treat patients with juxtarenal abdominal aortic aneurysm (AAA), pararenal AAA, and thoracoabdominal aortic aneurysms (TAAAs).

METHODS

A prospectively held database maintained at our department was queried for patients who have undergone branched and fenestrated stent grafting for AAA or TAAA treatment. Indication for repair, comorbidity precluding open repair, technical challenges associated with the repair, as well as operative mortality, morbidity, and reintervention rate were evaluated.

RESULTS

A total of 8 patients underwent repair with a fenestrated or branched stent graft. All patients had aneurysmal degeneration of the juxtarenal aorta, pararenal aorta, and thoracoabdominal aorta not suitable to standard endovascular techniques. Two patients had a prior aortic repair, a failed migrated stent graft, and an old surgical tube graft after an open repair. One patient had a type III TAAA and 1 patient had a postdissection TAAA type I. For all patients, target vessel success rate was 96.4% (27/28) and mean hospital stay was 6.0 days (range 3-21). Thirty-day and 1-year mortality were 0%. Mean follow-up was 23 months (range 7-45). Two endoleaks occurred, 1 type III and 1 type II, which were treated endovascularly. No death or major complication occurred during follow-up.

CONCLUSIONS

Fenestrated and branched endovascular stent grafts can be used to repair juxtarenal AAA, pararenal AAA, and TAAA in patients with significant comorbidities. However, several technical challenges have to be overcome due to the unique complex aortic pathology of each patient.