Early and Late Aortic-Related Mortality and Rupture After Fenestrated-Branched Endovascular Aortic Repair of Thoracoabdominal Aortic Aneurysms: A Prospective Multicenter Cohort Study.

BACKGROUND: Fenestrated-branched endovascular aortic repair (FB-EVAR) has been used as a minimally invasive alternative to open surgical repair to treat patients with thoracoabdominal aortic aneurysms (TAAAs). The aim of this study was to evaluate aortic-related mortality (ARM) and aortic aneurysm rupture after FB-EVAR of TAAAs. METHODS: Patients enrolled in 8 prospective, nonrandomized, physician-sponsored investigational device exemption studies between 2005 and 2020 who underwent elective FB-EVAR of asymptomatic intact TAAAs were analyzed. Primary end points were ARM, defined as any early mortality (30 days or in hospital) or late mortality from aortic rupture, dissection, organ or limb malperfusion attributable to aortic disease, complications of reinterventions, or aortic rupture. Secondary end points were early major adverse events, TAAA life-altering events (defined as death, permanent spinal cord injury, permanent dialysis, or stroke), all-cause mortality, and secondary interventions. RESULTS: A total of 1109 patients were analyzed; 589 (53.1%) had extent I-III and 520 (46.9%) had extent IV TAAAs. Median age was 73.4 years (interquartile range, 68.1-78.3 years); 368 (33.2%) were women. Early mortality was 2.7% (n=30); congestive heart failure was associated with early mortality (odds ratio, 3.30 [95% CI, 1.22-8.02]; P=0.01). Incidence of early aortic rupture was 0.4% (n=4). Incidence of early major adverse events and TAAA life-altering events was 20.4% (n=226) and 7.7% (n=85), respectively. There were 30 late ARMs; 5-year cumulative incidence was 3.8% (95% CI, 2.6%-5.4%); older age and extent I-III TAAAs were independently associated with late ARM (each P<0.05). Fourteen late aortic ruptures occurred; 5-year cumulative incidence was 2.7% (95% CI, 1.2%-4.3%); extent I-III TAAAs were associated with late aortic rupture (hazard ratio, 5.85 [95% CI, 1.31-26.2]; P=0.02). Five-year all-cause mortality was 45.7% (95% CI, 41.7%-49.4%). Five-year cumulative incidence of secondary intervention was 40.3% (95% CI, 35.8%-44.5%). CONCLUSIONS: ARM and aortic rupture are uncommon after elective FB-EVAR of asymptomatic intact TAAAs. Half of the ARMs occurred early, and most of the late deaths were not aortic related. Late all-cause mortality rate and the need for secondary interventions were 46% and 40%, respectively, 5 years after FB-EVAR. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifiers: NCT02089607, NCT02050113, NCT02266719, NCT02323581, NCT00583817, NCT01654133, NCT00483249, NCT02043691, and NCT01874197.

The Impact of Sex on Antiplatelet and Anticoagulant Thromboprophylaxis in Patients with Peripheral Artery Disease Post-revascularization.

OBJECTIVE: The aim of this prospective study was to 1) objectively quantify the impact of sex on platelet function in patients with PAD taking antiplatelet and anticoagulant medications and 2) to develop and test a personalized, iterative algorithm which personalizes thromboprophylaxis that incorporates platelet function testing. SUMMARY BACKGROUND DATA: Women with Peripheral Artery Disease (PAD) have worse outcomes as compared to their male counterparts in spite of having lower risk factors. This health disparity may be mitigated by personalizing thromboprophylaxis regimens. METHODS: Patients undergoing revascularization were enrolled. Serial thromboelastography (TEG) and TEG with Platelet Mapping (TEG-PM) was performed up to 6-months post-operatively to determine objective coagulation profiles. In a subset of patients, the Antiplatelet Coagulation Exactness (ACE) algorithm was implemented where patients were iteratively evaluated with TEG and given antiplatelet medications to maintain platelet inhibition at >29%. Statistical analysis was performed using unpaired t-test, ANOVA and Fisher's exact test. RESULTS: One hundred and eighty-one patients met study criteria. 58(32%) patients were females and 123(68%) were males. In the Aspirin cohort, females showed significantly greater clot strength as Maximum Amplitude - Arachidonic Acid (MAAA) and significantly lower platelet inhibition than males: [37.26 vs.32.38, P<0.01] and [52.95% vs.61.65%, P<0.05], respectively. In the Clopidogrel cohort, females showed higher Maximum Amplitude - Adenosine Diphosphate (MAADP) [42.58 vs.40.35, P=NS] compared to males. Females on dual antiplatelet therapy had higher MAADP [39.74 vs.35.07, P=NS] and lower platelet inhibition [45.25% vs.54.99%, P=NS] than males. The incidence of thrombosis of the revascularized segment, defined as thrombotic event, was objectively identified on an arterial duplex. Women showed significantly higher thrombotic events than men [22.95% vs.10.57%, P<0.05] on the same medication. In our pilot study, implementation of the ACE algorithm led to a significant decrease in the thrombosis rate (3%), including non-thrombotic events for females, vs. the historic thrombotic rate (22%) from our institution. CONCLUSIONS: Women with PAD exhibited higher platelet reactivity, clot strength, and reduced platelet inhibition in response to antiplatelet therapy. The use of the ACE algorithm to tailor antiplatelet medication in patients with PAD post-revascularization, resulted in a significant decrease in thrombotic event rates. This may serve as an opportune way to mitigate outcome sex-specific disparities caused by inadequate thromboprophylaxis in women.

Assessment of fitness for open repair in patients with infrarenal abdominal aortic aneurysms.

OBJECTIVE: Endovascular aortic repair (EVAR) was originally designed as a treatment modality for patients with abdominal aortic aneurysms (AAAs) deemed unfit for open repair. However, the definition of "unfit for open repair" is largely subjective and heterogenous. The purpose of this study was to compare patients deemed unfit for open repair who underwent EVAR to a matched cohort who underwent open repair for infrarenal AAAs. METHODS: The Vascular Quality Initiative of the Society for Vascular Surgery was queried for patients who underwent EVAR and open infrarenal AAA repair from 2003 to 2022. Patients that underwent EVAR were included if they were deemed unfit for open repair by the operating surgeon. EVAR patients deemed unfit because of a hostile abdomen were excluded. Patients in both the open and EVAR datasets were excluded if their repair was deemed non-elective or if they had prior aortic surgery. EVAR patients were matched to a cohort of open patients. The primary outcome for this study was 1-year mortality. Secondary outcomes included 30-day mortality, major adverse cardiac events, pulmonary complications, non-home discharge, reinterventions, and 5-year survival. RESULTS: A total of 5310 EVAR patients were identified who were deemed unfit for open repair. Of those, 3028 EVAR patients (57.0%) were able to be matched 1:1 to a cohort of open patients. Open patients had higher rates of major adverse cardiac events (20.2% vs 4.4%; P < .001), pulmonary complications (12.8% vs 1.6%; P < .001), non-home discharges (28.5% vs 7.9%; P < .001), and 30-day mortality (4.5% vs 1.4%; P < .001). There were no differences in early survival, but open repair had better middle and late survival compared with EVAR over the course of 5 years. A total of 74 EVAR patients (2.4%) had reinterventions during the study period. EVAR patients that required interventions had higher 1-year (40.5% vs 7.3%; P < .001) and 5-year mortality (43.2% vs 14.1%; P < .001) compared with those that did not require reinterventions. EVAR patients who had reinterventions had higher 1-year (40.5% vs 6.3%; P < .001) and 5-year (43.2% vs 20.3%; P = .006) mortality compared with their matched open cohort. CONCLUSIONS: Patients undergoing EVAR for AAAs who are deemed unfit for open repair have better perioperative morbidity and mortality compared with open repair. However, patients who had an open repair had better middle and late survival over the course of 5 years. The categorization of unfitness for open surgery may be inaccurate and re-evaluation of this terminology/concept should be undertaken.

Prospective randomized pilot trial comparing prophylactic and therapeutic cerebrospinal fluid drainage during complex endovascular thoracoabdominal aortic aneurysm repair.

BACKGROUND: Endovascular techniques have transformed the management of thoracoabdominal aortic aneurysms (TAAAs). However, spinal cord ischemia (SCI) remains a prevalent and devastating complication. Prophylactic drainage of cerebrospinal fluid (CSF) is among the proposed strategies for prevention of SCI. Although prophylactic CSF drainage is widely used and conceptually attractive, prophylactic CSF drains have not been demonstrated to definitively prevent the occurrence nor mitigate the severity of SCI in endovascular TAAA repair. Whether or not outcomes of prophylactic drains are superior to therapeutic drains remains unknown. This pilot study was performed to determine the feasibility of a randomized clinical trial designed to investigate the role of prophylactic vs therapeutic CSF drains in the prevention of SCI in patients undergoing endovascular TAAA repair using branched and fenestrated endovascular aortic repair (FBEVAR). METHODS: This was a prospective multicenter randomized pilot clinical trial conducted at The University of Alabama at Birmingham and The University of Massachusetts. Twenty patients were enrolled and randomized to either the prophylactic drainage or therapeutic drainage groups, prior to undergoing FBEVAR for extensive TAAAs and arch aortic aneurysms. This was a pilot feasibility study that was not powered to detect statistical differences in clinical outcomes. The primary outcome was feasibility of randomization and compliance with a shared lumbar drain protocol. Secondary outcomes included rate of drain complications and SCI. RESULTS: Twenty patients were enrolled and successfully randomized, without any crossovers, to either the control cohort (n = 10), without prophylactic drains, or the experimental cohort (n = 10), with prophylactic drains. There were no differences in age, comorbidities, or history of prior aortic surgery across the cohorts. All patients were treated with FBEVAR. Aneurysm classifications were as follows: Extent I (10%), Extent II (50%), Extent III (35%), and Extent IV (5%). The average length of aortic coverage was 207 ± 21.6 mm. The length of aortic coverage did not vary across cohorts, nor did procedural times or blood loss volume. Compliance with the SCI prevention protocol was 100% across both groups. Within the prophylactic drain cohort, one patient experienced an adverse event related to lumbar drain placement, manifested as an epidural hematoma requiring laminectomy, without neurologic deficit (n = 1/10; 10%). There was one SCI event (n = 1/20; 5%), which occurred in the prophylactic drain cohort on postoperative day 9 following an episode of hypotension related to a gastrointestinal bleed. CONCLUSIONS: The role of prophylactic CSF drains for the prevention of SCI following endovascular TAAA repair is a topic of ongoing research, with many current practices based on expert opinion and experience, rather than rigorous scientific data. This study demonstrates the feasibility of a multicenter randomized clinical trial to evaluate the role of prophylactic vs therapeutic CSF drains in the prevention of SCI in patients undergoing endovascular TAAA repair.

Preoperative risk factors for 1-year mortality in patients undergoing fenestrated endovascular aortic aneurysm repair in the US Aortic Research Consortium.

BACKGROUND: Early survival (1-year) after elective repair of complex abdominal aortic aneurysms (AAA) or thoracoabdominal aortic aneurysms (TAAA) can be used as an indicator of successful repair and provides a reasonable countermeasure to the annual rupture risk based on diameter. We aimed to identify preoperative factors associated with 1-year mortality after fenestrated or branched endovascular aortic repair (F/BEVAR) and develop a predictive model for 1-year mortality based on patient-specific risk profiles. METHODS: The US-Aortic Research Consortium database was queried for all patients undergoing elective F/BEVAR for complex AAA (cAAA) or TAAA from 2005 to 2022. The primary outcome was 1-year survival based on preoperative risk profile. Multivariable Cox regression was used to determine preoperative variables associated with 1-year mortality overall and by extent of aortic pathology. Logistic regression was performed to build a predictive model for 1-year mortality based on number of risk factors present. RESULTS: A total of 2099 patients met the inclusion criteria for this study (cAAA: n = 709 [34.3%]; type 1-3 TAAA: n = 777 [37.6%]; type 4-5 TAAA: n = 580 [28.1%]). Multivariable Cox regression identified the following significant risk factors associated with 1-year mortality: current smoker, chronic obstructive pulmonary disease, congestive heart failure (CHF), aortic diameter >7 cm, age >75 years, extent 1-3, creatinine >1.7 mg/dL, and hematocrit <36%. When stratified by extent of aortic involvement, multivariable Cox regression revealed risk factors for 1-year mortality in cAAA (CHF maximum aortic diameter >7 cm, hematocrit <36 mg/dL, and current smoking status), type 1-3 TAAA (chronic obstructive pulmonary disease, CHF, and age >75 years), and type 4-5 TAAA (age >75 years, creatinine >1.7 mg/dL, and hematocrit <36 mg/dL). Logistic regression was then used to develop a predictive model for 1-year mortality based on patient risk profile. Appraisal of the model revealed an area under the curve of 0.64 (P < .001), and an observed to expected ratio of 0.85. CONCLUSIONS: This study describes multiple risk factors associated with an increase in 1-year mortality after F/BEVAR. Given that elective repair of cAAA or TAAA is offered to some patients in whom future rupture risk outweighs operative risk, these findings suggest that highly comorbid patients with smaller aneurysms may not benefit from repair. Descriptive and predictive models for 1-year mortality based on patient risk profiles can serve as an adjunct in clinical decision-making when considering elective F/BEVAR.

Effect of fenestration configuration on renal artery outcomes during fenestrated-branched endovascular aortic repair.

OBJECTIVE: The aim of this study was to evaluate the effect of fenestration configuration and fenestration gap on renal artery outcomes during fenestrated-branched endovascular aortic repair (F/BEVAR). METHODS: A retrospective multicenter analysis was performed, including patients with complex aortic aneurysms treated with F/BEVAR that incorporated at least one small fenestration to a renal artery. The renal fenestrations were divided into groups 1 (8 × 6 mm) and 2 (6 × 6 mm). Primary patency, target vessel instability (TVI), freedom from secondary interventions (SIs), occurrence of type IIIc endoleak, all related to the renal arteries, were analyzed at 30-day, 1-year, and 5-year landmarks. The fenestration gap (FG) distance was analyzed as a modifier, and clustering was addressed at the patient level. RESULTS: A total of 796 patients were included in this study, 71.7% male, with a mean age of 73.3 ± 8.1 years. The mean follow-up was 30.0 ± 20.6 months. Of the 1474 small renal fenestrations analyzed, 47.6% were 8 × 6 mm, and 52.4% were 6 × 6 mm. At the 30-day landmark, primary patency (99.9% vs 98.0%; P value < .001 for groups 1 and 2, respectively), freedom from TVI (99.6% vs 97.1%; P value < .001 for groups 1 and 2, respectively), and freedom from SI (99.8% vs 98.4%; P value = .022 for groups 1 and 2, respectively) were higher in 8 × 6 compared with 6 × 6 fenestrations, and the incidence of acute kidney injury was similar across the groups (92.6% vs 92.7%; P value = .953 for groups 1 and 2 respectively). The primary patency at 1 and 5 years was higher in 8 × 6 fenestrations (1-year: 98.8% vs 96.9%; 5-year: 97.8% vs 95.7%, for groups 1 and 2, respectively, P values = .010 and .021 for 1 and 5 year comparisons, respectively). The freedom from SIs was significantly higher among 6 × 6 fenestrations at 5 years (93.1% vs 96.4%, for groups 1 and 2, respectively, P value = .007). The groups were equally as likely to experience a type Ic endoleak (1.3% and 1.6% for 8 × 6 and 6 × 6mm fenestrations, respectively, P = .689). The 6 × 6 fenestrations were associated with higher risk of kidney function deterioration (17.8%) when compared with 8 × 6 fenestrations (7.6%) at 5 years (P < .001). The risk of type IIIc endoleak was significantly higher among 8 × 6 fenestrations at 5 years (4.9% and 2% for 8 × 6 and 6 × 6 mm fenestrations, respectively; P = .005). A FG ≥5 mm negatively impacted the cumulative 5-year freedom from TVI (group 1: FG ≥5 mm = 0.714, FG <5 mm = 0.857; P < .001; group 2: FG ≥5 mm = 0.761, FG <5 mm = 0.929; P < .001) and the cumulative 5-year freedom from type IIIc endoleak (group 1: FG ≥5 mm = 0.759, FG <5 mm = 0.921; P = .034; group 2: FG ≥5 mm = 0.853, FG <5 mm = 0.979; P < .001) in both groups and the cumulative 5-year patency in group 2 (group 1: FG ≥5 mm = 0.963, FG <5 mm = 0.948; P = .572; group 2: FG ≥5 mm = 0.905, FG <5 mm = 0.938; P = .036). CONCLUSIONS: Fenestration configuration for the renal arteries impacts outcomes. The 8 × 6 small fenestrations have better patency at 30 days, 1 year, and 5 years, whereas 6 × 6 small fenestrations are associated with lower rates of SIs, primarily due to a lower incidence of type IIIc endoleaks. FG ≥5 mm at the level of the renal arteries significantly impacts the freedom from TVI, freedom from type IIIc endoleak, and 5-year patency independently of the fenestration size or vessel diameter.

Identifying risk factors for postoperative ileus following open abdominal aortic aneurysm repair.

INTRODUCTION: Postoperative ileus (POI) is a common complication following major abdominal surgery. The majority of the data available regarding POI following abdominal surgery is from the gastrointestinal and urologic literature. These data have been extrapolated to vascular surgery, especially with regards to enhanced recovery programs for open abdominal aortic aneurysm (AAA) surgery. However, vascular patients are a unique patient population and extrapolation of gastrointestinal and urological data may not necessarily be appropriate. Therefore, the purpose of this study was to delineate the prevalence and risk factors of POI in patients undergoing open AAA surgery. METHODS: This was a retrospective, single-institution study of patients who underwent open AAA surgery from January 2016 to July 2023. Patients were excluded if they had undergone non-elective repairs or had expired within 72 hours of their index operation. The primary outcome was rates of POI, which was defined as the presence of two or more of the following after the third postoperative day: nausea and/or vomiting, inability to tolerate oral food intake, absence of flatus, abdominal distension, or radiological evidence of ileus. RESULTS: A total of 123 patients met study criteria with an overall POI rate of 8.9% (n=11). Patients who developed a POI had significantly lower BMIs (24.3 kg/m2 versus 27.1 kg/m2, P=.003), were more likely to undergo a transperitoneal approach (81.8% versus 42.0%, P=.022), midline laparotomy (81.8% versus 37.5%, P=.008), longer total clamp times (151.6 minutes versus 97.7 minutes, P=.018), larger amounts of intraoperative crystalloid infusion (3495 mL versus 2628 mL, P=.029), and were more likely to return to the operating room (27.3% versus 3.6%, P=.016). Proximal clamp site was not associated with POI (P=.463). POI patients also had higher rates of post-operative vasopressor use (100% versus 61.1%, P=.014) and larger amounts of oral morphine equivalents in the first 3 post-operative days (488.0 mg + 216.0 versus 203.8 mg + 29.6 P=.016). Patients who developed POI had longer lengths of stay (12.5 days versus 7.6 days, P<.001), longer duration of NGT decompression (5.9 days versus 2.2 days, P<.001), and a longer period of time before diet tolerance (9.1 days versus 3.7 days, P<.001). Of those that developed a POI (n=11), 4 (36.4%) required total parental nutrition during the admission. CONCLUSION: POI is a morbid complication amongst patients undergoing elective open AAA surgery that significantly prolongs hospital stay. Patients at risk for developing a POI are those with lower BMIs, had an operative repair via a transperitoneal approach, midline laparotomy, longer clamp times, larger amounts of intraoperative crystalloid infusion, a return to the operating room, post-operative vasopressor use, and higher amounts of oral morphine equivalents. These data highlight important peri-operative opportunities to reduce the prevalence of POI.

Outcomes utilizing inverted iliac limb bifurcate components in fenestrated/branched endografting.

INTRODUCTION: Utilization of standard bifurcate pieces in fenestrated/branched endovascular aortic repair (F/BEVAR) requires adequate length from the lowest branch or fenestration to the aortic bifurcation. In patients with prior aortic surgery, the aortic bifurcation is often artificially established in a more proximal position, compromising the infrarenal length, which hinders the placement of a standard bifurcate component below the fenestrated/branched component. Short bifurcate bodies utilizing an inverted contralateral limb have been purpose-built to address this challenge. However, reported outcomes for this device remain limited, with specific concerns about the durability of the inverted iliac limb sealing region. We sought to evaluate outcomes of F/BEVAR utilizing an investigational inverted iliac limb bifurcate, manufactured by Cook Medical. METHODS: This study was a retrospective review of prospectively maintained data from the US-Aortic Research Consortium (US-ARC) from 2005-2022. Patients were included if they underwent F/BEVAR for thoracoabdominal or complex abdominal aortic aneurysms. Patients were excluded if they did not have a bifurcate device placed. Patients were then compared based on the utilization of an inverted iliac limb or standard bifurcate component. The primary outcome for this study was technical success. Secondary outcomes included 30-day mortality, freedom from ischemic leg complications, freedom from type 1 endoleaks (T1ELs), freedom from type 2 endoleaks (T2ELs), freedom from type 3 endoleaks (T3ELs), and graft component separations. RESULTS: A total of 1,944 patients met study criteria with 442 (22.8%) inverted iliac limb bifurcates and 1,502 (77.2%) standard bifurcates. Patients who received inverted iliac limbs were more likely to have had prior aortic surgery (63.8% versus 28.5%, P<.001). Patients receiving inverted iliac limbs had longer procedure times (265 minutes [IQR 201-342 minutes] versus 241 minutes [IQR 186-313 minutes], P<.001), more contrast usage (89 mL [IQR 55-135] versus 109 mL [IQR 75-156 mL], P<.001), and higher estimated blood loss (250 mL [IQR 150-500 mL] versus 250 mL [IQR 110-400 mL], P=.042). There were no differences in rates of technical success (97.3% versus 96.1%, P=.310), rates of endoleaks upon completion of the case (18.0% versus 21.4%, P=.123) or 30-day mortality (1.8% versus 2.5%, P=.466) between patients receiving inverted bifurcates and standard bifurcated components. There were no differences in cumulative survival, freedom from limb ischemia, freedom from aneurysm rupture, and freedom from T3ELs over the course of 5 years between patients receiving inverted bifurcates and standard bifurcated components. Patients with inverted iliac limb bifurcate components had decreased freedom from reinterventions, T1ELs, and T2ELs. After adjustment of potential confounders, the use of an inverted iliac limb was not associated with reinterventions (HR 1.044, 95 % CI 0.849-1.285, P=.682). There was a total of 2 (0.1%) component separations of the bifurcate component from the fenestrated/branched component over the study period, both of which occurred in the standard bifurcate components. CONCLUSION: The use of investigational inverted iliac limb bifurcate components is a safe option with favorable mid-term outcomes in patients who are not anatomic candidates for standard bifurcate components. Patients undergoing investigational inverted iliac limb bifurcate component implantation had decreased freedom from reinterventions which likely corresponds to the complexity of repair associated with them.

Practice patterns of antiplatelet and anticoagulant therapy after fenestrated/branched endovascular aortic repair.

OBJECTIVE: Antiplatelet and/or anticoagulant therapy are commonly prescribed after fenestrated/branched endovascular aortic repair (F/BEVAR). However, the optimal regimen remains unknown. We sought to characterize practice patterns and outcomes of antiplatelet and anticoagulant use in patients who underwent F/BEVAR. METHODS: Consecutive patients enrolled (2012-2023) as part of the United States Aortic Research Consortium (US-ARC) from 10 independent physician-sponsored investigational device exemption studies were evaluated. The cohort was characterized by medication regimen on discharge from index F/BEVAR: (1) Aspirin alone OR P2Y12 alone (single-antiplatelet therapy [SAPT]); (2) Anticoagulant alone; (3) Aspirin + P2Y12 (dual-antiplatelet therapy [DAPT]); (4) Aspirin + anticoagulant OR P2Y12 + anticoagulant (SAPT + anticoagulant); (5) Aspirin + P2Y12 + anticoagulant (triple therapy [TT]); and (6) No therapy. Kaplan-Meier analysis and Cox proportional hazards modeling were used to compare 1-year outcomes including survival, target artery patency, freedom from bleeding complication, freedom from all reinterventions, and freedom from stent-specific reintervention. RESULTS: Of the 1525 patients with complete exposure and outcome data, 49.6% were discharged on DAPT, 28.8% on SAPT, 13.6% on SAPT + anticoagulant, 3.2% on TT, 2.6% on anticoagulant alone, and 2.2% on no therapy. Discharge medication regimen was not associated with differences in 1-year survival, bleeding complications, composite reintervention rate, or stent-specific reintervention rate. However, there was a significant difference in 1-year target artery patency. On multivariable analysis comparing with SAPT, DAPT conferred a lower hazard of loss of target artery patency (hazard ratio [HR], 0.48; 95% confidence interval [CI], 0.27-0.84; P = .01). On sub-analyses of renal stents alone or visceral stents alone, DAPT no longer had a significantly lower hazard of loss of target artery patency (renal: HR, 0.66; 95% CI, 0.35-1.27; P = .22; visceral: HR, 0.31; 95% CI, 0.05-1.9; P = .21). Lastly, duration of DAPT therapy (1 month, 6 months, or 1 year) did not significantly affect target artery patency. CONCLUSIONS: Practice patterns for antiplatelet and anticoagulant regimens after F/BEVAR vary widely across the US-ARC. There were no differences in bleeding complications, survival or reintervention rates among different regimens, but higher branch vessel patency was noted in the DAPT cohort. These data suggest there is a benefit in DAPT therapy. However, the generalizability of this finding is limited by the retrospective nature of this data, and the clinical significance of this finding is unclear, as there is no difference in survival, bleeding, or reintervention rates amongst the different regimens. Hence, an "optimal" regimen, including the duration of such regimen, could not be clearly discerned. This suggests equipoise for a randomized trial, nested within this cohort, to identify the most effective antiplatelet/anticoagulant regimen for the growing number of patients being treated globally with F/BEVAR.

Postdissection aortic aneurysm sac enlargement after fenestrated and branched endovascular aortic aneurysm repair.

OBJECTIVES: Aneurysm sac changes after fenestrated-branched endovascular aneurysm repair (FBEVAR) for postdissection thoracoabdominal aortic aneurysms (PD-TAAs) are poorly understood. Partial thrombosis of the false lumen and endoleaks may impair sac regression. To characterize sac changes after FBEVAR for PD-TAAs, this study examined midterm results and predictors for sac enlargement. METHODS: FBEVARs performed for PD-TAAs in 10 physician-sponsored investigational device exemption studies from 2008 to 2023 were analyzed. The maximum aortic aneurysm diameter was compared between the 30-day computed tomography angiogram and follow-up imaging studies. Aneurysm sac enlargement was defined as an increase in diameter of ≥5 mm. Kaplan-Meier curves and Cox regression were used to evaluate sac enlargement and midterm FBEVAR outcomes. RESULTS: Among 3296 FBEVARs, 290 patients (72.4% male; median age, 68.4 years) were treated for PD-TAAs. Most aneurysms treated were extent II (72%) and III (12%). Mean aneurysm diameter was 66.5 ± 11.2 mm. Mortality at 30 days was 1.4%. At a mean follow-up of 2.9 ± 1.9 years, at least one follow-up imaging study revealed sac enlargement in 43 patients (15%), sac regression in 115 patients (40%), and neither enlargement nor regression in 137 (47%); 5 (2%) demonstrated both expansion and regression during follow-up. Freedom from aneurysm sac enlargement was 93%, 82%, and 80% at 1, 3, and 5 years, respectively. Overall, endoleaks were detected in 27 patients (63%) with sac enlargement and 143 patients (58%) without enlargement (P = .54). Sac enlargement was significantly more frequent among older patients (mean age at the index procedure, 70.2 ± 8.9 years vs 66.5 ± 11 years; P = .04) and those with type II endoleaks at 1 year (74% vs 52%; P = .031). Cox regression revealed age >70 years at baseline (hazard ratio [HR], 2.146; 95% confidence interval [CI], 1.167-3.944; P = .010) and presence of type II endoleak at 1 year (HR, 2.25; 95% CI, 1.07-4.79; P = .032) were independent predictors of sac enlargement. Patient survival was 92%, 81%, and 68% at 1, 3, and 5 years, respectively. Cumulative target vessel instability was 7%, and aneurysm-related mortality was 2% at 5 years. At least 42% of patients required secondary interventions. Sac enlargement did not affect patient survival. CONCLUSIONS: Aneurysm sac enlargement occurs in 15% of patients after FBEVAR for PD-TAAs. Elderly patients (>70 years at baseline) and those with type II endoleaks at 1 year may need closer monitoring and secondary interventions to prevent sac enlargement. Despite sac enlargement in some patients, aneurysm-related mortality at 5 years remains low and overall survival was not associated with sac enlargement.

Complications of Carotid Interventions for Symptomatic Lesions after Systemic Thrombolysis.

BACKGROUND: Series detailing complications after carotid endarterectomy (CEA) and transfemoral carotid stenting (tfCAS) for patients presenting with neurologic symptoms that are treated with systemic thrombolysis (ST) are sparse. We sought to determine if treatment with ST was associated with a higher rate of post-carotid intervention complications. METHODS: A multispecialty, institutional, prospectively maintained database was queried for symptomatic patients treated with CEA or tfCAS from 2007 to 2019. The primary outcomes of interest were bleeding complications (access/wound complications, hematuria, intracranial hemorrhage) or need for reintervention, stroke, and death. We compared rates of these outcomes between patients who were and were not treated with ST. To adjust for preoperative patient factors and confounding variables, propensity scores for assignment to ST and non-ST were calculated. RESULTS: There were 1,139 patients included (949 [82%] CEA and 190 [17%] tfCAS. All treated lesions were symptomatic (550 [48%] stroke, 603 [52%] transient ischemic attack). Fifty-six patients (5%) were treated with ST. Fifteen of 56 patients also underwent catheter-based intervention for stroke. ST was administered 0 to 1 day preoperatively in 21 (38%) patients, 2 to 6 days preoperatively in 27 (48%) patients, and greater than 6 days preoperatively in 8 (14%) patients. ST patients were more likely to present with stroke (93% vs. 45%; P < 0.001) and have higher preoperative Rankin scores. Unadjusted rate of bleeding/return to operating room was 3% for ST group and 3% for non-ST group (P = 0.60). Unadjusted rate of stroke was 4% for ST group and 3% for the non-ST group (P = 0.91), while perioperative mortality was 5% for ST group and 1% for non-ST group (P = 0.009). After adjusting for patient factors, preoperative antiplatelet/anticoagulation, and operative factors, ST was not associated with an increased odds of perioperative bleeding/return to the operating room (odds ratio 0.37; 95% confidence interval: 0.02-1.63; P = 0.309) or stroke (odds ratio 0.62; 95% confidence interval: 0.16-2.40; P = 0.493). CONCLUSIONS: ST does not convey a higher risk of complications after CEA or tfCAS. After controlling for other factors, patients that received ST had similar rates of local complications and stroke when compared to non-ST patients. Early carotid intervention is safe in patients that have received ST, and delays should be avoided in symptomatic patients given the high risk of recurrent stroke.

Local Anesthesia for Endovascular Repair of Abdominal Aortic Aneurysm Allows for Accurate Graft Deployment with Durable Results.

BACKGROUND: Local anesthesia (LA) is sparsely used in endovascular aneurysm repair (EVAR) despite short-term benefit, likely secondary to concerns over patient movement preventing accurate endograft deployment. The objective of this study is to examine the association between anesthesia type and endoleak, sac regression, reintervention, and mortality. METHODS: The Vascular Quality Initiative database was queried for all EVAR cases from 2014 to 2022. Patients were included if they underwent percutaneous elective EVAR with anatomical criteria within instructions for use of commercially approved endografts. Multivariable logistic regression with propensity score weighting was used to determine the association between anesthesia type on the risk of any endoleak noted by intraoperative completion angiogram and sac regression. Multivariable survival analysis with propensity score weighting was used to determine the association between anesthesia type and endoleak at 1 year, long-term reintervention, and mortality. RESULTS: Thirteen thousand nine hundred thirty two EVARs met inclusion criteria: 1,075 (8%) LA and 12,857 (92%) general anesthesia (GA). On completion angiogram, LA was associated with fewer rates of any endoleaks overall (16% vs. 24%, P < 0.001). On multivariable analysis with propensity score weighting, LA was associated with similar adjusted odds of any endoleak on intraoperative completion angiogram (odds ratio [OR] 0.56, 95% confidence interval [CI] 0.47-0.68) as well as combined type 1a and type 1b endoleaks (OR 0.72, 95% CI 0.47-1.09). Follow-up computed tomography imaging at 1 year was available for 4,892 patients, 377 (8%) LA and 4,515 (92%) GA. At 1 year, LA was associated with similar rate of freedom from any endoleaks compared to GA (0.66 [95% CI 0.63-0.69] vs. 0.71 [95% CI 0.70-0.72], P = 0.663) and increased rates of sac regression (50% vs. 45%, P = 0.040). On multivariable analysis with propensity score weighting, LA and GA were associated with similar adjusted odds of sac regression (OR 1.22, 95% CI 0.97-1.55). LA and GA had similar rates of endoleak at 1 year (hazard ratio [HR] 0.14, 95% CI 0.63-1.07); however, LA was associated with decreased hazards of combined type 1a and 1b endoleaks at 1 year (HR 0.87, 95% CI 0.80-0.96). LA and GA had similar adjusted long-term reintervention rate (HR 0.77, 95% CI 0.44-1.38) and long-term mortality (HR 1.100, 95% CI 079-1.25). CONCLUSIONS: LA is not associated with increased adjusted rates of any endoleak on completion angiogram or at 1-year follow-up compared to GA. LA is associated with decreased adjusted rates of type 1a and type 1b endoleak at 1 year, but similar rates of sac regression, long-term reintervention, and mortality. Concerns for accurate graft deployment should not preclude use of LA and LA should be increasingly considered when deciding on anesthetic type for standard elective EVAR.

Multicenter CT Image-Based Anatomic Assessment of Patients with Aortoiliac Aneurysm Undergoing Endovascular Repair with Iliac Branch Devices.

BACKGROUND: The Global Iliac Branch Study (NCT05607277) is an international, multicenter, retrospective cohort study of anatomic predictors of adverse iliac events (AIEs) in aortoiliac aneurysms treated with iliac branch devices (IBDs). METHODS: Patients with pre-IBD and post-IBD computed tomography imaging were included. We measured arterial diameters, stenosis, calcification, bifurcation angles, and tortuosity indices using a standardized, validated protocol. A composite of ipsilateral AIE was defined, a priori, as occlusion, type I or III endoleak, device constriction, or clinical event requiring reintervention. Paired t-test compared tortuosity indices and splay angles pretreatment and post-treatment for all IBDs and by device material (stainless steel and nitinol). Two-sample t-test compared anatomical changes from pretreatment to post-treatment by device material. Logistic regression assessed associations between AIE and anatomic measurements. Analysis was performed by IBD. RESULTS: We analyzed 297 patients (286 males, 11 females) with 331 IBDs (227 stainless steel, 104 nitinol). Median clinical follow-up was 3.8 years. Iliac anatomy was significantly straightened with all IBD treatment, though stainless steel IBDs had a greater reduction in total iliac artery tortuosity index and aortic splay angle compared to nitinol IBDs (absolute reduction -0.20 [-0.22 to -0.18] vs. -0.09 [-0.12 to -0.06], P < 0.0001 and -19.6° [-22.4° to -16.9°] vs. -11.2° [-15.3° to -7.0°], P = 0.001, respectively). There were 54 AIEs in 44 IBDs in 42 patients (AIE in 13.3% of IBD systems), requiring 35 reinterventions (median time to event 41 days; median time to reintervention 153 days). There were 18 endoleaks, 29 occlusions, and 5 device constrictions. There were no strong associations between anatomic measurements and AIE overall, though internal iliac diameter was inversely associated with AIE in nitinol devices (nAIE, nitinol = 8). CONCLUSIONS: Purpose-built IBDs effectively treat aortoiliac disease, including that with tortuous anatomy, with a high patency rate (91.5%) and low reintervention rate (9.1%) at 4 years. Anatomic predictors of AIE are limited.

Image-based assessment of aortoiliac aneurysm anatomical characteristics in patients from the global iliac branch study.

OBJECTIVE: Endovascular repair is the preferred treatment for aortoiliac aneurysm, with preservation of at least one internal iliac artery recommended. This study aimed to assess pre-endovascular repair anatomical characteristics of aortoiliac aneurysm in patients from the Global Iliac Branch Study (GIBS, NCT05607277) to enhance selection criteria for iliac branch devices (IBD) and improve long-term outcomes. METHODS: Pre-treatment CT scans of 297 GIBS patients undergoing endovascular aneurysm repair were analyzed. Measurements included total iliac artery length, common iliac artery length, tortuosity index, common iliac artery splay angle, internal iliac artery stenosis, calcification score, and diameters in the device's landing zone. Statistical tests assessed differences in anatomical measurements and IBD-mediated internal iliac artery preservation. RESULTS: Left total iliac artery length was shorter than right (6.7 mm, P = .0019); right common iliac artery less tortuous (P = .0145). Males exhibited greater tortuosity in the left total iliac artery (P = .0475) and larger diameter in left internal iliac artery's landing zone (P = .0453). Preservation was more common on right (158 unilateral, 34 bilateral) than left (105 unilateral, 34 bilateral). There were 192 right-sided and 139 left-sided IBDs, with 318 IBDs in males and 13 in females. CONCLUSION: This study provides comprehensive pre-treatment iliac anatomy analysis in patients undergoing endovascular repair with IBDs, highlighting differences between sides and sexes. These findings could refine patient selection for IBD placement, potentially enhancing outcomes in aortoiliac aneurysm treatment. However, the limited number of females in the study underscores the need for further research to generalize findings across genders.

Mid-term Renal and Mesenteric Artery Outcomes During Fenestrated and Branched Endovascular Aortic Repair for Complex Abdominal and Thoracoabdominal Aortic Aneurysms in the United States Aortic Research Consortium.

OBJECTIVE: To report mid-term outcomes of renal-mesenteric target arteries (TAs) after fenestrated-branched endovascular aortic repair (FB-EVAR) of complex abdominal and thoracoabdominal aortic aneurysm. BACKGROUND: TA instability (TAI) is the most frequent indication for reintervention after FB-EVAR. METHODS: Data from consecutive patients enrolled in 9 prospective nonrandomized physician-sponsored investigational device exemption studies between 2005 and 2020 were reviewed. TA outcomes through 5 years of follow-up were analyzed for vessels incorporated by fenestrations or directional branches (DBs), including TA patency, endoleak, integrity failure, reintervention, and instability. RESULTS: A total of 1681 patients had 6349 renal-mesenteric arteries were targeted using 3720 fenestrations (59%), 2435 DBs (38%), and 194 scallops (3%). Mean follow was 23 ± 21 months. At 5 years, TAs incorporated by fenestrations had higher primary (95 ± 1% vs 91 ± 1%, P < 0.001) and secondary patency (98 ± 1% vs 94 ± 1%, P < 0.001), and higher freedom from TAI (87 ± 2% vs 84 ± 2%, P = 0.002) compared with TAs incorporated by DBs, with no differences in other TA events. DBs targeted by balloon-expandable stent-grafts had significantly lower freedom from TAI (78 ± 4% vs 88 ± 1%, P = 0.006), TA endoleak (87 ± 3% vs 97 ± 1%, P < 0.001), and TA reintervention (83 ± 4% vs 95 ± 1%, P < 0.001) compared with those targeted by self-expandable stent-grafts. CONCLUSIONS: Incorporation of renal and mesenteric TA during FB-EVAR is safe and durable with high 5-year patency rates and low freedom from TAI. DBs have lower patency rates and lower freedom from TAI than fenestrations, with better performance for self-expandable stent grafts as compared with balloon-expandable stent grafts.

Outcomes of Elective and Non-elective Fenestrated-branched Endovascular Aortic Repair for Treatment of Thoracoabdominal Aortic Aneurysms.

OBJECTIVE: To describe outcomes after elective and non-elective fenestrated-branched endovascular aortic repair (FB-EVAR) for thoracoabdominal aortic aneurysms (TAAAs). BACKGROUND: FB-EVAR has been increasingly utilized to treat TAAAs; however, outcomes after non-elective versus elective repair are not well described. METHODS: Clinical data of consecutive patients undergoing FB-EVAR for TAAAs at 24 centers (2006-2021) were reviewed. Endpoints including early mortality and major adverse events (MAEs), all-cause mortality, and aortic-related mortality (ARM), were analyzed and compared in patients who had non-elective versus elective repair. RESULTS: A total of 2603 patients (69% males; mean age 72±10 year old) underwent FB-EVAR for TAAAs. Elective repair was performed in 2187 patients (84%) and non-elective repair in 416 patients [16%; 268 (64%) symptomatic, 148 (36%) ruptured]. Non-elective FB-EVAR was associated with higher early mortality (17% vs 5%, P <0.001) and rates of MAEs (34% vs 20%, P <0.001). Median follow-up was 15 months (interquartile range, 7-37 months). Survival and cumulative incidence of ARM at 3 years were both lower for non-elective versus elective patients (50±4% vs 70±1% and 21±3% vs 7±1%, P <0.001). On multivariable analysis, non-elective repair was associated with increased risk of all-cause mortality (hazard ratio, 1.92; 95% CI] 1.50-2.44; P <0.001) and ARM (hazard ratio, 2.43; 95% CI, 1.63-3.62; P <0.001). CONCLUSIONS: Non-elective FB-EVAR of symptomatic or ruptured TAAAs is feasible, but carries higher incidence of early MAEs and increased all-cause mortality and ARM than elective repair. Long-term follow-up is warranted to justify the treatment.

A pilot study to evaluate a novel localized treatment to stabilize small- to medium-sized infrarenal abdominal aortic aneurysms.

OBJECTIVE: There is no proven therapy to reduce growth rates of small- to medium-sized abdominal aortic aneurysms (AAAs). Ex vivo and animal studies have demonstrated that a novel stabilizing agent, 1,2,3,4,6-pentagalloyl glucose (PGG), delivered locally to the aneurysm sac, can bind to elastin and collagen to re-establish strength and resist enzymatic degradation. We aimed to demonstrate that a one-time administration of PGG solution to the aneurysm wall is safe and potentially effective to slow the growth of small- to medium-sized AAAs. METHODS: Patients with small- to medium-sized infrarenal AAAs (maximum diameter <5.5 cm) were recruited. Via transfemoral access, a 14F or 16F dual-balloon delivery catheter was introduced into the aneurysm sac. A single, 3-minute, localized endoluminal infusion of PGG was delivered via a 'weeping' balloon to the aneurysm wall. Independent core laboratory measurements of maximum aneurysm sac diameter and sac volume measurements based on computed tomography angiography (CTA) were used for assessments at 1, 6, 12, 24, and 36 months. The primary endpoints were technical success and safety (major adverse events at 30 days). The secondary endpoint was growth stabilization, defined as freedom from aneurysm sac enlargement (diameter increase >5 mm per year or volume increase of >10% per year). RESULTS: Twenty patients (19 male) were enrolled at five centers from May 2019 to June 2022 (mean age, 67.8 years; range, 50-87 years). All procedures were technically successful. The safety profile was consistent with standard interventional procedures. Four patients demonstrated transient elevations of liver enzymes levels that returned to normal by 30 days with no clinical symptoms. Through November 2022, follow-up CTA data is available on the first 11 patients. The average changes in maximum aneurysm diameter from baseline to 6, 12, 24, and 36 months were 0.2 mm, 1.1 mm, 1.2 mm, and 0.8 mm, respectively, and the average changes in volume were 2.0%, 9.6%, 18.1%, and 11.6%, respectively. At 12 months, none of the aneurysms showed growth >5.0 mm, and three had volume growth >10%. CONCLUSIONS: The early results of this first-in-human, small cohort study demonstrated that a single, localized PGG administration to patients with small- to medium-sized infrarenal AAAs is safe. Longer term follow-up on all 20 treated patients is needed to better assess the potential impact on aneurysm growth.

Aneurysm extent-based mortality differences in complex endovascular repair of thoracoabdominal aneurysms in the Vascular Quality Initiative and the United States Aortic Research Consortium.

BACKGROUND: Endovascular management of thoracoabdominal aneurysms (TAAA) is becoming more common. Technological advances including custom devices under the Physician-Sponsored Investigational Device Exemption (PS-IDE), physician-modified endografts (PMEG), and parallel stenting techniques have expanded the extent of disease that is amenable to endovascular treatment. Patients within the PS-IDE studies are a highly selected group of patients, whereas patients treated with PMEG as captured within the Society for Vascular Surgery Vascular Quality Initiative (SVS VQI) represent a real-world experience. Research within both the SVS VQI on PMEG and the US Aortic Research Consortium (US-ARC) has demonstrated a relationship between extent of aneurysmal disease and mortality after complex endovascular TAAA repair, but no direct comparison of these cohorts has been conducted. In this study, we sought to compare outcomes of custom PS-IDE devices with off-label uses of commercially available devices for the endovascular management of TAAAs. METHODS: A retrospective review of patients presenting for elective endovascular TAAA repair for asymptomatic disease between 2011 and 2019 was conducted within both the SVS VQI registry and the US-ARC. Patients within the SVS VQI registry were treated with either PMEG or with parallel stenting techniques. Patients within the US-ARC were treated with PS-IDE custom devices. The extent of aneurysm disease was defined by the deployment zones documented for the devices entered in the registry using Crawford extents I to V. Primary outcomes were 30-day and 1-year mortality rates. RESULTS: A total of 3212 patients were included in the study: 1571 PMEG/parallel stenting within the VQI registry and 1641 with PS-IDE within the US-ARC database. The majority of patients presented with extent IV aneurysms (n = 1827 [57%]), with extent IV aneurysms being slightly more prevalent within the US-ARC cohort. Maximal aneurysm diameter within each extent did not vary between the US-ARC and VQI cohorts. Across all patients, the 30-day mortality was 4.4% and the 1-year mortality was 12.2%. Unadjusted mortality at 30-days was 6.7% within the VQI, and 2.2% in the US-ARC (P < .001). The unadjusted 1-year mortality was 14.3% within the VQI and 10.2% within the US-ARC (P < .001). When adjusted for aneurysm extent, similar differences in 30-day and 1-year survivals were identified. CONCLUSIONS: Patients treated in PS-IDE studies had better 30-day and 1-year survival rates compared with those treated with a similar extent of disease using off-label approaches in a real-world registry. These differences are complex and likely associated with a number of factors, including arterial anatomy, patient comorbidities, device construct, and volume outcomes, as well as complex and unmeasurable surgeon- and patient-specific factors.

Partial and complete explantation of aortic endografts in the modern era.

OBJECTIVE: Despite the progressive advancement of devices for endovascular aortic repair (EVAR), endografts continue to fail, requiring explant. We present a single-institutional experience of EVAR explants, characterizing modern failure modes, presentation, and outcomes for partial and complete EVAR explantation. METHODS: A retrospective analysis was performed of all EVARs explanted at an urban quaternary center from 2001 to 2020, with one infected endograft excluded. Patient and graft characteristics, indications, and perioperative and long-term outcomes were analyzed. Partial versus complete explants were performed per surgeon discretion without a predefined protocol. This process was informed by patient risk factors; asymptomatic, symptomatic, or ruptured aneurysm presentation; and anatomical or intraoperative factors, including endoleak type. RESULTS: From 2001 to 2020, 52 explants met the inclusion and exclusion criteria. More than one-half (57.7%) were explants of EVAR devices placed at outside institutions, designated nonindex explants. Most patients were male (86.5%), the median age was 74 years (interquartile range, 70-78 years). More than one-half (61.5%) were performed in the second decade of the study period. The most commonly explanted grafts were Gore Excluder (n = 9 grafts), Cook Zenith (n = 8), Endologix AFX (n = 7), Medtronic Endurant (n = 5), and Medtronic Talent (n = 5). Most grafts (78.8%) were explanted for neck degeneration or sac expansion. Five were explanted for initial seal failure, five for symptomatic expansion, and seven for rupture. The median implant duration was 4.2 years, although ranging widely (interquartile range, 2.6-5.1 years), but similar between index and nonindex explants (4.2 years vs 4.1 years). Partial explantation was performed in 61.5%, with implant duration slightly lower, 3.2 years versus 4.4 years for complete explants. Partial explantation was more frequent in index explants (68.2% vs 56.7%). The median length of stay was 8 days. The median intensive care unit length of stay was 3 days, without significant differences in nonindex explants (4 days vs 3 days) and partial explants (4 days vs 3 days). Thirty-day mortality occurred in two nonindex explants (one partial and one complete explant). Thirty-day readmission was similar between partial and complete explants (9.7% vs 5.0%), without accounting for nonindex readmissions. Long-term survival was comparable between partial and complete explants in Cox regression (hazard ratio, 2.45; 95% confidence interval, 0.79-7.56; P = .12). CONCLUSIONS: Explants of EVAR devices have increased over time at our institution. Partial explant was performed in more than one-half of cases, per operating surgeon discretion, demonstrating higher blood loss, more frequent acute kidney injury, and longer intensive care unit stays, however with comparable short-term mortality and long-term survival.

Severity of acute kidney injury is associated with decreased survival after fenestrated and branched endovascular aortic aneurysm repair.

OBJECTIVE: Acute kidney injury (AKI) occurs frequently in complex aortic surgery and has been implicated in perioperative and long-term survival. This study sought to characterize the relationship between AKI severity and mortality after fenestrated and branched endovascular aortic aneurysm repair (F/B-EVAR). METHODS: Consecutive patients enrolled by the US Aortic Research Consortium in 10, prospective, nonrandomized, physician-sponsored investigational device exemption studies evaluating F/B-EVAR, between 2005 and 2023, were included in this study. Perioperative AKI during hospitalization was defined by and staged using the 2012 Kidney Disease Improving Global Outcomes criteria. Determinants of AKI were evaluated with backward stepwise mixed effects multivariable ordinal logistic regression. Survival was analyzed with conditionally adjusted survival curves and backward stepwise mixed effects Cox proportional hazards modelling. RESULTS: In the study period, 2413 patients with a median (interquartile range [IQR]) age of 74 years (IQR, 69-79 years) underwent F/B-EVAR. The median follow-up duration was 2.2 years (IQR, 0.7-3.7 years). The median baseline estimated glomerular filtration rate (eGFR) and creatinine were 68 mL/min/1.73 m2 (IQR, 53-84 mL/min/1.73 m2) and 1.1 mg/dL (IQR, 0.9-1.3 mg/dL), respectively. Stratification of AKI identified 316 patients (13%) with stage 1 injury, 42 (2%) with stage 2 injury, and 74 (3%) with stage 3 injury. Renal replacement therapy was initiated during the index hospitalization in 36 patients (1.5% of cohort, 49% of stage 3 injuries). Thirty-day major adverse events were associated with AKI severity (all P ≤ .0001). Multivariable predictors of AKI severity included baseline eGFR (proportional odds ratio, 0.9 per 10 mL/min/1.73 m2 [95% confidence interval (CI), 0.85-0.95 per 10 mL/min/1.73 m2]; P < .0001), baseline serum hematocrit (0.58 per 10% [95% CI, 0.48-0.71 per 10%]; P < .0001), renal artery technical failure during aneurysm repair (3 [95% CI,1.61-5.72]; P = .0006), and total operating time (1.05 per 10 minutes [95% CI, 1.04-1.07 per 10 minutes]; P < .0001). One-year unadjusted survivals for AKI severity strata were 91% (95% CI, 90%-92%) for no injury, 80% (95% CI, 76%-85%) for stage 1 injury, 72% (95% CI, 59-87%) for stage 2 injury, and 46% (95% CI, 35-59%) for stage 3 injury (P<.0001). Multivariable determinants of survival included AKI severity (stage 1, hazard ratio [HR], 1.6 [95% CI, 1.3-2]); stage 2, HR, 2.2 [95% CI, 1.4-3.4]); stage 3 HR, 4 [95% CI, 2.9-5.5]; P < .0001), decreased eGFR (HR, 1.1 [95% CI, 0.9-1.3]; P = .4), patient age (HR, 1.6 per 10 years [95% CI, 1.4-1.8 per 10 years]; P < .0001), baseline chronic obstructive pulmonary disease (HR, 1.5 [95% CI, 1.3-1.8]; P < .0001), baseline congestive heart failure (HR, 1.7 [95% CI, 1.6-2.1]; P < .0001), postoperative paraplegia (HR, 2.1 [95% CI, 1.1-4]; P = .02), and procedural technical success (HR, 0.6 [95% CI, 0.4-0.8]; P = .003). CONCLUSIONS: AKI, as defined by the 2012 Kidney Disease Improving Global Outcomes criteria, occurred in 18% of patients after F/B-EVAR. Greater severity of AKI after F/B-EVAR was associated with decreased postoperative survival. The predictors of AKI severity identified in these analyses suggest a role for improved preoperative risk mitigation and staging of interventions in complex aortic repair.