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.

Pilot study to improve resident experience on vascular surgery by standardizing dissemination of operative steps.

OBJECTIVE: Many surgical residencies have passed along attendings preferences and procedural knowledge as a highly utilized but informal resource. The objective was to assess the effect of providing operative steps and attending preferences on surgical resident performance. DESIGN: This was a prospective observational study with a survey-based design. SETTING: We created and shared vascular surgery operative steps including institutional and attending preferences with junior residents at the Massachusetts General Hospital. PARTICIPANTS: There were a total of 31 residents who completed a survey to assess self-perception of performance in operative knowledge and Accreditation Council for Graduate Medical Education (ACGME) Milestone criteria. RESULTS: Advice from colleagues was the most utilized resource, followed by web-based materials. Of the web-based materials, almost all residents utilized Google searches over other web-based resources designed to specifically help surgical trainees. The vascular surgery resource was used by 90% of residents more than 3 times per week to prepare for operative cases. There was significant improvement in patient positioning, instrument selection, operative field exposure, anatomy, sequence of procedure, procedure choices, and peri-operative care knowledge. CONCLUSIONS: Development of institutional resources that specifically capture attending surgeon procedural variations can improve resident performance, encourage resident autonomy, and provide a catalog of approaches to challenging operative situations.

An International, Expert-based, Delphi Consensus Document on Controversial Issues in the Management of Abdominal Aortic Aneurysms.

OBJECTIVE: As a result of conflicting, inadequate or controversial data in the literature, several issues concerning the management of patients with abdominal aortic aneurysms (AAAs) remain unanswered. The aim of this international, expert-based Delphi Consensus document was to provide some guidance for clinicians on these controversial topics. METHODS: A 3-Round Delphi Consensus document was produced with 44 experts on 6 pre-specified topics regarding the management of AAAs. All answers were provided anonymously. The response rate for each round was 100%. RESULTS: Most participants (42 of 44; 95.4%) agreed that a minimum case volume/year is essential (or probably essential) for a center to offer open/endovascular AAA repair (EVAR). Furthermore, 33 of 44 (75.0%) believed that AAA screening programs are (probably) still clinically effective and cost-effective. Additionally, most panelists (36 of 44; 81.9%) voted that surveillance after EVAR should be (or should probably be) lifelong. Finally, 35 of 44 (79.7%) participants thought that women smokers should (or should probably/possibly) be considered for screening at 65 years of age similar to men. No consensus was achieved regarding lowering the threshold for AAA repair and the need for deep venous thrombosis prophylaxis in patients undergoing EVAR. CONCLUSIONS: This expert-based Delphi Consensus document provides guidance for clinicians regarding specific unresolved issues. Consensus could not be achieved in some topics, highlighting the need for further research in those areas.

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.

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.

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.

Effect of EVAR on International Ruptured AAA Mortality-Sex and Geographic Disparities.

Background: We sought to investigate the differential impact of EVAR (endovascular aneurysm repair) vis-à-vis OSR (open surgical repair) on ruptured AAA (abdominal aortic aneurysm) mortality by sex and geographically. Methods: We performed a retrospective study of administrative data on EVAR from state statistical agencies, vascular registries, and academic publications, as well as ruptured AAA mortality rates from the World Health Organization for 14 14 states across Australasia, East Asia, Europe, and North America. Results: Between 2011-2016, the proportion of treatment of ruptured AAAs by EVAR increased from 26.1 to 43.8 percent among females, and from 25.7 to 41.2 percent among males, and age-adjusted ruptured AAA mortality rates fell from 12.62 to 9.50 per million among females, and from 34.14 to 26.54 per million among males. The association of EVAR with reduced mortality was more than three times larger (2.2 vis-à-vis 0.6 percent of prevalence per 10 percentage point increase in EVAR) among females than males. The association of EVAR with reduced mortality was substantially larger (1.7 vis-à-vis 1.1 percent of prevalence per 10 percentage point increase in EVAR) among East Asian states than European+ states. Conclusions: The increasing adoption of EVAR coincided with a decrease in ruptured AAA mortality. The relationship between EVAR and mortality was more pronounced among females than males, and in East Asian than European+ states. Sex and ethnic heterogeneity should be further investigated.

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.

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.

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.

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.

Room for improvement in patient compliance during peripheral vascular interventions.

Introduction: For patients receiving Procedural Sedation and Analgesia (PSA), patient cooperation is crucial as patients remain continuously aware of operating room activity and can be asked to perform tasks such as prolonged breath-holds. This survey aimed to collect information on patient compliance with on-table instructions and its relation to periprocedural outcomes from surgeons nationwide performing peripheral vascular interventions (PVI) under PSA. Methods: A 9-question online survey was sent to 383 vascular surgeons (including both vascular surgery attendings and trainees) across the United States through REDCap from August 30 to September 21, 2021, with responses closed on October 30, 2021. The survey response was analyzed with descriptive statistics. Results: 83 (21.6%) vascular surgeons responded to the survey, of which 67 (80.7%) were attending vascular surgeons and 16 (19.3%) were vascular surgery trainees. 41 (49.4%) respondents performed 11-20 PVI cases under PSA every month, while 31 (41.0%) respondents performed 1-10 PVI cases under PSA every month. 41 (49.4%) respondents reported that in 1-10% of their cases, additional contrast and/or radiation was administered because patient moved on the table or did not cooperate with breath holds; 25 (30.1%) reported that this occurred in 11-20% of their cases, 12 (14.5%) reported that this occurred in 21-50% of their cases and 4 (4.8%) reported that this occurred in over 50% of their cases. In such cases, the majority of respondents reported a 1-10% increase in contrast volume (59.0%), radiation dosage (62.7%), sedative/analgesia administration (46.3%) and procedural time (54.9%). Of cases being converted to general anesthesia due to inadequate patient cooperation, 35 (42.2%) respondents reported between 1-5 per month, and 3 (3.6%) respondents reported between 6-10 per month. Of cases being aborted due to inadequate patient cooperation, 25 (30.1%) respondents reported between 1-5 per month, and 1 (1.2%) respondents reported between 6-10 per month. Conclusion: A significant fraction of PVI cases performed under PSA result in increased radiation and contrast exposure, sedative administration and procedural time due to inadequate patient cooperation. In certain cases, conversion to general anesthesia or case abortion is required. Further research should be performed to investigate strategies to minimize such adverse patient safety events.

Iliac artery aneurysm endoleak management in a patient with vascular Ehlers-Danlos syndrome.

Endovascular repair has traditionally been avoided in patients with connective tissue disorders. We describe successful treatment of multiple endoleaks of an expanding common iliac artery aneurysm previously treated with an endograft in a patient with vascular Ehlers-Danlos syndrome. The modalities used to treat the endoleaks were transgluteal embolization of the internal iliac artery and proximal and distal extension of the prior endograft. This case demonstrates endovascular management of endoleaks in patients with vascular Ehlers-Danlos syndrome can be safe and feasible.

Implementation of a Consensus-Driven Quality Improvement Protocol to Decrease Length of Stay after Elective Carotid Endarterectomy.

BACKGROUND: National guidelines stipulate that postoperative length-of-stay (LOS) after elective carotid endarterectomy (CEA) should not exceed 1 day on average, yet perioperative care coordination gaps may limit the ability for institutions to achieve this goal. Internal review determined that increased LOS after CEA at our institution was frequently attributable to urinary retention or postoperative hypertension. We designed and implemented a quality improvement (QI) protocol aiming to better our institutional performance in postoperative LOS after CEA, consisting of 2 Plan-Do-Study-Act (PDSA) cycles. METHODS: In the first PDSA cycle, a division-wide standardized protocol was developed by which antihypertensive medications were managed preoperatively and through postoperative day (POD) 1. This protocol included dedicated patient outreach with instructions for at-home antihypertensive management through the morning of POD 0. Second, alpha-1-blockade was administered to all male patients preoperatively. All patients receiving an elective CEA performed at our institution by vascular surgeons were included in the protocol. The primary outcome measure was defined percent failure of the LOS >1 day metric, with raw LOS as a secondary outcome measure. Process measures included adherence to the antihypertensive medication protocol and adherence to preoperative alpha-1 blockade. Balance measures included documented intraoperative hypotension and 30-day readmission. Fisher's exact test was used to evaluate relationships between preintervention and postintervention cohorts and the outcome measure. Wilcoxon rank-sum tests were used to evaluate relationships between cohorts and total LOS. RESULTS: Baseline performance on the LOS >1 day metric after elective CEA was 58.3% in the 8 months prior to intervention, across 48 patients. Both PDSA interventions were implemented simultaneously. In the 12 months after intervention, 64 patients met protocol inclusion criteria, including 19 symptomatic patients (29.7%). Process measure success for preoperative antihypertensive regimen adherence was 89.8%. For males not chronically prescribed alpha-1 blockade preoperatively, process measure success for adherence to preoperative alpha-1 blockade was 78.8%. The intraoperative hypotension balance measure occurred in 1 patient (1.6%). Performance on the LOS >1 day outcome measure was improved to 32.8% (P = 0.01). Performance on the raw LOS outcome measure was similar between the preintervention cohort (median 2 days, interquartile range [IQR] 1-2) and postintervention cohort (median 1 day, IQR 1-2, P = 0.07). Performance on the 30-day readmission balance measure was similar between preintervention (6.3%) and postintervention cohorts (9.4%, P = 0.73). CONCLUSIONS: The consensus-driven development and implementation of a QI protocol to reduce postoperative LOS after CEA showed promising results in our institution, with approximately 40% improvement in the primary outcome measure. Wider efforts to improve LOS after CEA should include a focus on minimization of postoperative hypertension and urinary retention.

Update of T-branch use from the US Aortic Research Consortium.

Aortic endograft evolution has altered our approach to treating patients with both standard and complex aortic disease. In particular, fenestrated and branched aortic endografts have allowed for the expansion of therapy to include those patients with extensive thoracoabdominal aortic aneurysms (TAAAs). The fenestrations and branches allow for the aortic endografts to achieve a seal in the proximal and distal aspects of the aorto-iliac tree, to exclude the aneurysm, while maintaining perfusion to the renal and visceral vessels. Historically, many of the grafts used for this purpose are custom made devices designed for a specific patient based on their preoperative computed tomography imaging. One downside to this approach is the time it takes to construct these grafts. Given this, much effort has been directed towards developing "off-the-shelf" grafts which may be applicable to many patients in an immediate-need bases. The Zenith T-Branch device offers an off-the-shelf graft with four directional branches. Its utilization is not applicable to all patients, but can be applied to many patients with TAAAs. Large reported series on outcomes for these devices is limited to centers in Europe as well as within the United States Aortic Research Consortium. While early outcomes appear excellent, long-term outcomes related to aneurysm exclusion, branch patency, and freedom from reintervention are needed and will be forthcoming.

Outcomes After Endovascular Aortic Intervention in Patients With Connective Tissue Disease.

Importance: Endovascular treatment is not recommended for aortic pathologies in patients with connective tissue diseases (CTDs) other than in redo operations and as bridging procedures in emergencies. However, recent developments in endovascular technology may challenge this dogma. Objective: To assess the midterm outcomes of endovascular aortic repair in patients with CTD. Design, Setting, and Participants: For this descriptive retrospective study, data on demographics, interventions, and short-term and midterm outcomes were collected from 18 aortic centers in Europe, Asia, North America, and New Zealand. Patients with CTD who had undergone endovascular aortic repair from 2005 to 2020 were included. Data were analyzed from December 2021 to November 2022. Exposure: All principal endovascular aortic repairs, including redo surgery and complex repairs of the aortic arch and visceral aorta. Main Outcomes and Measures: Short-term and midterm survival, rates of secondary procedures, and conversion to open repair. Results: In total, 171 patients were included: 142 with Marfan syndrome, 17 with Loeys-Dietz syndrome, and 12 with vascular Ehlers-Danlos syndrome (vEDS). Median (IQR) age was 49.9 years (37.9-59.0), and 107 patients (62.6%) were male. One hundred fifty-two (88.9%) were treated for aortic dissections and 19 (11.1%) for degenerative aneurysms. One hundred thirty-six patients (79.5%) had undergone open aortic surgery before the index endovascular repair. In 74 patients (43.3%), arch and/or visceral branches were included in the repair. Primary technical success was achieved in 168 patients (98.2%), and 30-day mortality was 2.9% (5 patients). Survival at 1 and 5 years was 96.2% and 80.6% for Marfan syndrome, 93.8% and 85.2% for Loeys-Dietz syndrome, and 75.0% and 43.8% for vEDS, respectively. After a median (IQR) follow-up of 4.7 years (1.9-9.2), 91 patients (53.2%) had undergone secondary procedures, of which 14 (8.2%) were open conversions. Conclusions and Relevance: This study found that endovascular aortic interventions, including redo procedures and complex repairs of the aortic arch and visceral aorta, in patients with CTD had a high rate of early technical success, low perioperative mortality, and a midterm survival rate comparable with reports of open aortic surgery in patients with CTD. The rate of secondary procedures was high, but few patients required conversion to open repair. Improvements in devices and techniques, as well as ongoing follow-up, may result in endovascular treatment for patients with CTD being included in guideline recommendations.

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.