Outcomes of Visceral Arterial Interposition Graft Reconstruction for Locally Advanced Pancreatic Cancer.

OBJECTIVE: The aim of this study is to determine perioperative outcomes and the patency of interposition conduits for visceral arterial reconstruction in this setting. SUMMARY BACKGROUND DATA: Visceral arterial encasement in locally advanced pancreatic cancer was historically a contraindication for surgery. With modern effective neoadjuvant strategies, our recent experience has made advanced vascular resection and reconstruction feasible in selected patients. METHODS: A retrospective review was performed of patients undergoing pancreatic tumor resection with en bloc arterial resection and interposition revascularization between 6/2002-10/2022. Endpoints included graft patency, vascular-related complications, reinterventions, morbidity, and mortality. RESULTS: Visceral arterial reconstruction with interposition grafting was performed in 111 patients undergoing en bloc arterial resections for pancreatic cancer. Graft types included autologous arterial conduits (n=66, 58 superficial femoral artery (SFA) and 8 splenic artery), cryopreserved arterial allografts (n=24), autologous saphenous veins (n=12), synthetic conduits (n=8), and composite autologous artery and synthetic (n=1). Perioperative 90-day mortality decreased significantly over time to 5% in the last six years. Vascular complications related to arterial reconstruction occurred in 11% (n=12) and included pseudoaneurysm (n=6), graft thrombus (n=2), stenosis requiring reintervention (n=2), hepatic failure (n=1), and hepatic and intestinal ischemia (n=1). Nine (8%) patients underwent vascular-related reinterventions. After median follow-up of 17-months, primary patency was 81% for the entire cohort and was highest in the SFA group (95%). The donor limb/harvest site complication rate was 8% with 100% primary patency. CONCLUSION: Visceral arterial resection with interposition reconstruction for locally advanced pancreatic cancer can be performed with acceptable vascular morbidity and durable patency. Autologous SFA was the most suitable conduit for reconstructions in our experience, with highest primary patency.

Cryopreserved arterial allografts vs autologous vein for arterial reconstruction in infected fields.

OBJECTIVE: Peripheral arterial infections are rare and difficult to treat when an in situ reconstruction is required. Autologous vein (AV) is the conduit of choice in many scenarios. However, cryopreserved arterial allografts (CAAs) are an alternative. We aimed to assess our experience with CAAs and AVs for reconstruction in primary and secondary peripheral arterial infections. METHODS: Data from patients with peripheral arterial infections undergoing reconstruction with CAA or AV from January 2002 through August 2022 were retrospectively analyzed. Patients with aortic- or iliac-based infections were excluded. RESULTS: A total of 42 patients (28 CAA, 14 AV) with a mean age of 65 and 69 years, respectively, were identified. Infections were secondary in 31 patients (74%) and primary in 11 (26%). Secondary infections included 10 femoral-femoral grafts, 10 femoropopliteal or femoral-distal grafts, five femoral patches, four carotid-subclavian grafts, one carotid-carotid graft, and one infected carotid patch. Primary infection locations included six femoral, three popliteal, and two subclavian arteries. In patients with lower extremity infections, associated groin infections were present in 19 (56%). Preoperative blood cultures were positive in 17 patients (41%). AVs included saphenous vein in eight and femoral vein in six. Intraoperative cultures were negative in nine patients (23%), polymicrobial in eight (21%), and monomicrobial in 22 (56%). Thirty-day mortality occurred in four patients (10%), two due to multisystem organ failure, one due to graft rupture causing acute blood loss and myocardial infarction, and one due to an unknown cause post-discharge. Median follow-up was 20 months and 46 months in the CAA and AV group, respectively. Graft-related reintervention was performed in six patients in the CAA group (21%) and one patient in the AV group (7%). Freedom from graft-related reintervention rates at 3 years were 82% and 92% in the CAA and AV group, respectively (P = .12). Survival rates at 1 and 3 years were 85% and 65% in the CAA group and 92% and 84% in the AV group (P = .13). Freedom from loss of primary patency was similar with 3-year rates of 77% and 83% in the CAA and AV group, respectively (P = .25). No patients in either group were diagnosed with reinfection. CONCLUSIONS: CAAs are an alternative conduit for peripheral arterial reconstructions when AV is not available. Although there was a trend towards higher graft-related reintervention rates in the CAA group, patency is similar and reinfection is rare.

Outcomes of lower extremity arterial bypass using the Human Acellular Vessel in patients with chronic limb-threatening ischemia.

OBJECTIVE: Patients with chronic limb-threatening ischemia (CLTI) and no great saphenous vein to use as a conduit for arterial bypass have a high risk for amputation despite advances in medical and endovascular therapies. This report presents findings from a U.S. Food and Drug Administration (FDA) supported study of the Human Acellular Vessel (HAV) (Humacyte Inc.) used as a conduit for arterial bypass in patients with CLTI and inadequate or absent autologous conduit. METHODS: The HAV is a 6-mm, 40-cm vessel created from human vascular smooth muscle cells seeded onto a polyglycolic acid scaffold pulsed in a bioreactor for 8 weeks as cells proliferate and the scaffold dissolves. The resultant vessel is decellularized, creating a nonimmunogenic conduit composed of collagen, elastin, and extracellular matrix. The FDA issued an Investigational New Drug for an intermediate-sized, single-center study of the HAV under the agency's Expanded Access Program in patients with advanced CLTI and inadequate or absent autologous conduit. Technical results and clinical outcomes were analyzed and reported. RESULTS: Between March 2021 and July 2023, 29 patients (20 males; mean age, 71 ± 11 years) underwent limb salvage operation using the HAV as a bypass conduit. Most patients had advanced CLTI (Rutherford class 5/6 in 72%; wound, ischemia, and foot infection stage 3/4 in 83%), and 97% had previously failed revascularization(s) of the extremity. Two HAVs were sewn together to attain the needed bypass length in 24 patients (83%). Bypasses were to tibial arteries in 23 patients (79%) and to the popliteal artery in 6 (21%). Technical success was 100%, and the 30-day mortality rate was 7% (2 patients). With 100% follow-up (median, 9.3 months), the limb salvage rate was 86% (25/29 patients). There were 16 reinterventions to restore secondary patency, of which 15 (94%) were successful. Primary and secondary patency of the HAV at 9 months were 59% and 71%, respectively. CONCLUSIONS: The HAV has demonstrated short- to intermediate-term safety and efficacy as an arterial bypass conduit in a complex cohort of patients with limb-threatening ischemia and no autologous options. This experience using the FDA's Expanded Access Program provides real-world data to inform regulatory deliberations and future trials of the HAV, including the study of the vessel as a first-line bypass conduit in less severe cases of chronic limb ischemia.

Comparative outcomes of arterial bypass using the human acellular vessel and great saphenous vein in patients with chronic limb ischemia.

OBJECTIVE: The Human Acellular Vessel (HAV) is a novel, off-the-shelf biologic conduit being evaluated for arterial reconstructions. Regulatory studies in peripheral arterial disease (PAD) to date have consisted of single-arm cohorts with no comparator groups to contrast performance against established standards. This study aimed to compare outcomes of the HAV with autologous great saphenous vein (GSV) in patients with advanced PAD undergoing infrageniculate bypass. METHODS: Patients with advanced PAD and no autologous conduit who underwent bypass with the 6-mm diameter HAV (Group 1; n = 34) (March 2021-February 2024) were compared with a multicenter historical cohort who had bypass with single-segment GSV (group 2; n = 88) (January 2017-December 2022). The HAV was used under an Investigational New Drug protocol issued by the Food and Drug Administration (FDA) under the agency's Expanded Access Program. RESULTS: Demographics were comparable between groups (mean age 69 ± 10 years; 71% male). Group 1 had higher rates of tobacco use (37 pack-years vs 28 pack-years; P = .059), coronary artery disease (71% vs 43%; P = .007), and prior coronary artery bypass grafting (38% vs 14%; P = .003). Group 1 had more patients classified as wound, ischemia, and foot infection clinical stage 4 (56% vs 33%; P = .018) and with previous index leg revascularizations (97% vs 53%; P < .001). Both groups had a similar number of patients with chronic limb-threatening ischemia (Rutherford class 4-6) (88% vs 86%; P = .693) and Global Anatomic Staging System stage III (91% vs 96%; P = .346). Group 1 required a composite conduit (two HAV sewn together) in 85% of bypasses. The tibial vessels were the target in 79% of group 1 and 100% of group 2 (P < .001). Group 1 had a lower mean operative time (364 minutes vs 464 minutes; P < .001). At a median of 12 months, major amputation-free survival (73% vs 81%; P = .55) and overall survival (84% vs 88%; P = .20) were comparable. Group 1 had lower rates of primary patency (36% vs 50%; P = .044), primary-assisted patency (45% vs 72%; P = .002), and secondary patency (64% vs 72%; P = .003) compared with group 2. CONCLUSIONS: Implanted under Food and Drug Administration Expanded Access provisions, the HAV was more likely to be used in redo operations and cases with more advanced limb ischemia than GSV. Despite modest primary patency, the HAV demonstrated resilience in a complex cohort with no autologous conduit options, achieving good secondary patency and providing major amputation-free survival comparable with GSV at 12 months.

Natural history and long-term outcomes of medically managed Type B intramural hematoma.

OBJECTIVE: Type B intramural hematoma (IMH) is often managed medically, yet may progress to dissection, aneurysmal dilation, or rupture. The aim of this study was to report the natural history of medically managed Type B IMH, and factors associated with progression. METHODS: We reviewed patients with medically managed Type B IMH between January 1995 to December 2022 at a single center. Any patients with immediate surgical or endovascular intervention were excluded. Demographic profiles, comorbidities, imaging, and follow-up details were reviewed. Patients were divided into two groups: Group 1 had isolated IMH, and Group 2 had IMH along with aneurysm or dissection at the time of presentation. On follow-up, progression was defined as degeneration to aneurysm/dissection or increase in the thickness of IMH in Group 1. In Group 2, progression was an increase in the size of aneurysm or development of new dissection. RESULTS: Of 104 patients with Type B IMH during the study period, 92 were medically managed. The median age was 77 years, and 45 (48.9%) were females. Comorbidities included hypertension (83.7%), hypercholesterolemia (44.6%), and active smoking (47.8%). Mean Society for Vascular Surger comorbidity score was 6.3. Mean IMH thickness and aortic diameter at presentation were 8.9 mm and 38.3 mm, respectively. Median follow-up was 55 months. Overall survival at 1 year and 5 years was 85.8% and 61.9%, respectively. During follow-up, 19 patients (20.7%) required intervention, more common in Group 2 (Group 1, 8/66; 12.3% vs Group 2, 11/26; 42.3%; P = .001). This resulted in higher freedom from intervention in Group 1 at 1 year (93.5% vs 62.7%) and 5 years (87.5% vs 51.1%; P < .001). Indication for intervention was dissection (n = 4), aneurysm (n = 12), and progression of IMH (n = 3). In Group 1, progression was seen in 25 (37.9%), three (4.5%) remained stable, 29 (43.9%) had complete resolution of IMH, and nine patients were lost to follow-up. In Group 2, 11 patients (42.3%) had progression, seven (26.9%) remained stable, and eight were lost to follow-up. IMH thickness at presentation >7.2 mm is associated with both increased odds of progression (odds ratio, 3.3; 95% confidence interval, 1.2-11.1; P = .03) and intervention (odds ratio, 5.5; 95% confidence interval, 1.3-36.9; P = .03) during the follow-up. CONCLUSIONS: Although many patients with Type B IMH managed medically stabilize or regress, progression or need for intervention can occur in up to 40% of cases. This is associated with the presence of aneurysm, dissection, and IMH thickness. Long-term follow-up is mandatory as late interventions occur, particularly for higher risk patients.

Implications and late outcomes of type II endoleaks after endovascular aneurysm repair.

OBJECTIVE: Type II endoleaks (T2ELs) are the most common cause of reintervention after endovascular aneurysm repair (EVAR). Although most resolve spontaneously, the long-term implications of T2ELs remain elusive. We aim to evaluate the impact of persistent and late T2ELs on clinical outcomes after EVAR. METHODS: This was a single-institution retrospective review of patients who underwent EVAR for degenerative infrarenal abdominal aortic aneurysm between January 2010 and June 2022 with no type I (T1EL) or III (T3EL) endoleak seen at EVAR completion. Patients were categorized based on T2EL status. Group 1 included patients with never detected or transient T2ELs (detected at EVAR completion but not after). Group 2 encompassed persistent T2ELs (seen at EVAR completion and again during follow-up) and late T2ELs (detected for the first time at any point during follow-up). Time-to-event analysis was conducted using a time-dependent approach to T2EL status. Primary outcomes included freedom from sac enlargement (SE), aneurysm-related reinterventions, and overall survival. RESULTS: A total of 803 patients met inclusion criteria. Group 1 included 418 patients (52%), of which 85% had no T2ELs and 15% had transient T2ELs. Group 2 had 385 patients; 23% had persistent T2ELs, and 77% developed a new T2EL. Patients in group 1 had a higher prevalence of smoking (88% vs 83%; P < .001), chronic obstructive pulmonary disease (33% vs 25%; P = .008), chronic kidney disease (13% vs 8%; P = .021), and a higher mean Society for Vascular Surgery score (7 vs 6 points; P = .049). No differences were found in aneurysm diameter or morphology. Mean follow-up was 5 years for the entire cohort. In Group 2, 58 patients (15%) underwent T2EL treatment, most commonly transarterial embolization. At 10 years after EVAR, Group 2 was associated with lower freedom from SE (P < .001) and abdominal aortic aneurysm-related reinterventions (P < .001) and comparable overall survival (P = .42). More T1ELs were detected during follow-up in Group 2 (6 [1%] vs 20 [5%]; P = .004), with 15 (75%) of these detected at a median of 3 years after the T2EL. No difference between groups was observed in explant (0.7% vs 2.1%; P = .130) or aneurysm rupture (0.5% vs 1.3%; P = .269) rates. CONCLUSIONS: One-half of patients treated with infrarenal EVAR developed persistent/late T2ELs, which are associated with a higher risk of SE and reinterventions. No difference in overall survival or aneurysm rupture risk was seen at 10 years, based on T2EL status or T2EL intervention. A conservative approach to T2ELs may be appropriate for most patients with absent T1ELs or T3ELs.

Characterization and surgical management of aberrant subclavian arteries.

OBJECTIVE: Aberrant subclavian arteries (aSCAs), with or without aortic pathology, are uncommon. The purpose of the present study was to review our experience with the surgical management of aSCA. METHODS: We performed a retrospective review of patients who had undergone surgery for an aSCA between 1996 and 2020. Symptomatic and asymptomatic patients were included. The primary end points were ≤30-day and late mortality. The secondary end points were ≤30-day complications, graft patency, and reinterventions. RESULTS: A total of 46 symptomatic and 3 asymptomatic patients with aSCA had undergone surgery (31 females [62%]; median age, 45 years). An aberrant right subclavian artery was present in 38 (78%) and an aberrant left subclavian artery in 11 patients (22%). Of the 49 patients, 41 (84%) had had a Kommerell diverticulum (KD) and 11 (22%) had had a concomitant distal arch or proximal descending thoracic aortic aneurysm. Symptoms included dysphagia (56%), dyspnea (27%), odynophagia (20%), and upper extremity exertional fatigue (16%). Five patients (10%) had required emergency surgery. The aSCA had been treated by transposition in 32, a carotid to subclavian bypass in 11, and an ascending aorta to subclavian bypass in 6. The KD was treated by resection and oversewing in 19 patients (39%). Fifteen patients (31%) had required distal arch or proximal descending thoracic aortic replacement for concomitant aortic disease and/or KD treatment. Thoracic endovascular aortic repair was used to exclude the KD in six patients (12%). Seven patients (14%) had undergone only bypass or transposition. The 30-day complications included one death from pulseless electrical activity arrest secondary to massive pulmonary embolism. The 30-day major complications (14%) included acute respiratory failure in three, early mortality in one, stroke in one, non-ST-elevation myocardial infarction in one, and temporary dialysis in one patient. The other complications included chylothorax/lymphocele (n = 5; 10%), acute kidney injury (n = 2; 4%), pneumonia (n = 2; 4%), wound infection (n = 2; 4%), atrial fibrillation (n = 2; 4%), Horner syndrome (n = 2; 4%), lower extremity acute limb ischemia (n = 1; 2%), and left recurrent laryngeal nerve injury (n = 1; 2%). At a median follow-up of 53 months (range, 1-230 months), 40 patients (82%) had had complete symptom relief and 9 (18%) had experienced improvement. Six patients had died at a median of 157 months; the deaths were not procedure or aortic related. The primary patency was 98%. Reintervention at ≤30 days had been required for two patients (4%) for ligation of lymphatic vessels and bilateral lower extremity fasciotomy after proximal descending thoracic aorta replacement. One patient had required late explantation of an infected and occluded carotid to subclavian bypass graft, which was treated by cryopreserved allograft replacement. CONCLUSIONS: Surgical treatment of the aSCA can be accomplished with low major morbidity and mortality with excellent primary patency and symptom relief.

Cryopreserved arterial allografts vs rifampin-soaked Dacron for the treatment of infected aortic and iliac grafts.

OBJECTIVE: Aortic and iliac graft infections remain complex clinical problems with high mortality and morbidity. Cryopreserved arterial allografts (CAAs) and rifampin-soaked Dacron (RSD) are options for in situ reconstruction. This study aimed to compare the safety and effectiveness of CAA vs RSD in this setting. METHODS: Data from patients with aortic and iliac graft infections undergoing in situ reconstruction with either CAA or RSD from January 2002 through August 2022 were retrospectively analyzed. Our primary outcomes were freedom from graft-related reintervention and freedom from reinfection. Secondary outcomes included comparing trends in the use of CAA and RSD at our institution, overall survival, perioperative mortality, and major morbidity. RESULTS: A total of 149 patients (80 RSD, 69 CAA) with a mean age of 68.9 and 69.1 years, respectively, were included. Endovascular stent grafts were infected in 60 patients (41 CAA group and 19 RSD group; P ≤ .01). Graft-enteric fistulas were more common in the RSD group (48.8% RSD vs 29.0% CAA; P ≤ .01). Management included complete resection of the infected graft (85.5% CAA vs 57.5% RSD; P ≤ .01) and aortic reconstructions were covered in omentum in 57 (87.7%) and 63 (84.0%) patients in the CAA and RSD group, respectively (P = .55). Thirty-day/in-hospital mortality was similar between the groups (7.5% RSD vs 7.2% CAA; P = 1.00). One early graft-related death occurred on postoperative day 4 due to CAA rupture and hemorrhagic shock. Median follow-up was 20.5 and 21.5 months in the CAA and RSD groups, respectively. Overall post-discharge survival at 5 years was similar, at 59.2% in the RSD group and 59.0% in the CAA group (P = .80). Freedom from graft-related reintervention at 1 and 5 years was 81.3% and 66.2% (CAA) vs 95.6% and 92.5% (RSD; P = .02). Indications for reintervention in the CAA group included stenosis (n = 5), pseudoaneurysm (n = 2), reinfection (n = 2), occlusion (n = 2), rupture (n = 1), and graft-limb kinking (n = 1). In the RSD group, indications included reinfection (n = 3), occlusion (n = 1), endoleak (n = 1), omental coverage (n = 1), and rupture (n = 1). Freedom from reinfection at 1 and 5 years was 98.3% and 94.9% (CAA) vs 92.5% and 87.2% (RSD; P = .11). Two (2.9%) and three patients (3.8%) in the CAA and RSD group, respectively, required graft explantation due to reinfection. CONCLUSIONS: Aorto-iliac graft infections can be managed safely with either CAA or RSD in selected patients for in situ reconstruction. However, reintervention was more common with CAA use. Freedom from reinfection rates in the RSD group was lower, but this was not statistically significant. Conduit choice is associated with long-term surveillance needs and reinterventions.

Incidence, reintervention, and survival associated with type II endoleak at hospital discharge after elective endovascular aneurysm repair in the Vascular Quality Initiative.

BACKGROUND: The longitudinal clinical significance of type II endoleaks (T2ELs) remains controversial. Specifically, the real-world incidence, need for reintervention, and associated mortality referable to T2ELs remain unknown. Moreover, current professional society clinical practice guidelines recommend differing aneurysm sac growth thresholds to prompt intervention. Therefore, the purpose of this analysis was to better quantify the prevalence of early T2ELs after infrarenal endovascular aortic aneurysm repair (EVAR) and determine its association with reintervention and survival. METHODS: All elective EVARs from the Vascular Quality Initiative (2010-2020) were examined to identify patients with isolated T2ELs vs no endoleak (NONE) at discharge. Procedures with a type I or III endoleak were excluded. A subgroup analysis was performed on patients surviving beyond the first postoperative year with follow-up data available on endoleaks. The primary outcome was overall survival. Secondary outcomes included perioperative mortality and reinterventions. Outcomes were assessed by multivariable logistic and Cox proportional hazards regression to adjust for covariates. RESULTS: We identified 53,697 patients who underwent EVAR. The overall incidence of isolated T2ELs at discharge was 16%. In-hospital mortality was lower for those with isolated T2ELs vs NONE (0.8% vs 1.9%, odds ratio: 0.6, 95% confidence interval: 0.5-0.8, P < .0001). Unadjusted overall survival was marginally higher at 5 years for patients with T2ELs vs NONE (84% vs 82%); however, after risk adjustment, survival was similar (hazard ratio: 0.95, 95% confidence interval: 0.9-1.0). Among 44,345 patients with 1-year follow-up, 66% had data on endoleak status for assessment. Survival was similar regardless of endoleak status (NONE, at discharge only, at follow-up only, or at both time points). Among patients with documented T2ELs during follow-up, 6.1% and 2.5% had abdominal aortic aneurysm sac diameter growth ≥5 mm and ≥10 mm, respectively. Reinterventions occurred in 12%. Rupture (1%) and any open reintervention (4%) were rare among patients with 1-year follow-up. For patients with T2ELs, 5-year survival was similar between those with and without reintervention by 1 year (89% vs 91%, log-rank P = .06). CONCLUSIONS: T2ELs remain common after EVAR within the Vascular Quality Initiative and are not associated with long-term mortality. Reinterventions for T2ELs were not associated with improved overall survival among patients with T2ELs. Although additional data surrounding the appropriate role of reintervention for T2ELs remain necessary, it appears that the natural history of T2ELs is benign.

Clinical presentation, operative management, and long-term outcomes of rupture after previous abdominal aortic aneurysm repair.

OBJECTIVE: The aim of the present study was to evaluate the presentation trends, intervention, and survival of patients who had been treated for late abdominal aortic aneurysm rupture (LAR) after open repair (OR) or endovascular aortic aneurysm repair (EVAR). METHODS: We reviewed the clinical data from a single-center, retrospective database for patients treated for LAR from 2000 to 2020. The end points were the 30-day mortality, major postoperative complication, and survival. The outcomes between LAR managed with EVAR (group I) vs OR were compared (group II). RESULTS: Of 390 patients with infrarenal aortic rupture, 40 (10%) had experienced aortic rupture after prior aortic repair and comprised the LAR cohort (34 men; age 78 ± 8 years). LAR had occurred before EVAR in 30 and before OR in 10 patients. LAR was more common in the second half of the study with 32 patients after 2010. LAR after prior OR was secondary to ruptured para-anastomotic pseudoaneurysms. After initial EVAR, LAR had occurred despite reintervention in 17 patients (42%). The time to LAR was shorter after prior EVAR than after OR (6 ± 4 vs 12 ± 4 years, respectively; P = .003). Treatment for LAR was EVAR for 25 patients (63%; group I) and OR for 15 (37%, group II). LAR after initial OR was managed with endovascular salvage for 8 of 10 patients. Endovascular management was more frequent in the latter half of the study period. In group I, fenestrated repair had been used for seven patients (28%). Salvage for the remaining cases was feasible with EVAR, aortic cuffs, or limb extensions. The incidence of free rupture, time to treatment, 30-day mortality (8% vs 13%; P = .3), complications (32% vs 60%; P = .1), and disposition were similar between the two groups. Those in group I had had less blood loss (660 vs 3000 mL; P < .001) and less need for dialysis (0% vs 33%; P < .001) than those in group II. The median follow-up was 21 months (interquartile range, 6-45 months). The overall 1-, 3-, and 5-year survival was 76%, 52%, and 41%, respectively, and was similar between groups (28 vs 22 months; P = .48). Late mortality was not related to the aorta. CONCLUSIONS: LAR after abdominal aortic aneurysm repair has been encountered more frequently in clinical practice, likely driven by the frequency of EVAR. However, most LARs, including those after previous OR, can now be salvaged with endovascular techniques with lower morbidity and mortality.

Vascular surgery integrated resident selection criteria in the pass or fail era.

OBJECTIVES: Vascular surgery integrated residency (VSIR) programs are highly competitive; however, criteria for resident selection remain opaque and non-standardized. The already unclear selection criteria will be further impacted by the impending transition of the United States Medical Licensing Examination (USMLE) Step 1 from numeric scores to a binary pass/fail outcome. The purpose of this study was to investigate the historical and anticipated selection criteria of VSIR applicants. METHODS: This was a cross-sectional, nationwide, 59-item survey that was sent to all VSIR program directors (PDs). Data was analyzed using the Fisher exact test if categorical and the Mann-Whitney U test and the Kruskal-Wallis test if ordinal. RESULTS: Forty of 69 PDs (58%) responded to the survey. University-based programs constituted 85% of responders. Most VSIR PDs (65%) reported reviewing between 101 to 150 applications for 1 to 2 positions annually. Forty-two percent of the responding PDs reported sole responsibility for inviting applicants to interview, whereas 50% had a team of faculty responsible for reviewing applications. On a five-point Likert scale, letters of recommendation (LOR) from vascular surgeons or colleagues (a person the PD knows) were the most important objective criteria. Work within a team structure was rated highest among subjective criteria. The majority of respondents (72%) currently use the Step 1 score as a primary method to screen applicants. Regional differences in use of Step 1 score as a primary screening method were: Midwest (100%), Northeast (76%), South (43%), and West (40%) (P = .01). PDs responded that that they will use USMLE Step 2 score (42%) and LOR (10%) to replace USMLE Step 1 score. The current top ranked selection criteria are letters from a vascular surgeon, USMLE Step 1 score and overall LOR. The proposed top ranked selection criteria after transition of USMLE Step 1 to pass/fail include LOR overall followed by Step 2 score. CONCLUSIONS: This is the first study to evaluate the selection criteria used by PDs for VSIR. The landscape of VSIR selection criteria is shifting and increasing transparency is essential to applicants' understanding of the selection process. The transition of USMLE Step 1 to a pass/fail report will shift the attention to Step 2 scores and elevate the importance of other relatively more subjective criteria. Defining VSIR program selection criteria is an important first step toward establishing holistic review processes that are transparent and equitable.

Contemporary outcomes after treatment of aberrant subclavian artery and Kommerell's diverticulum.

OBJECTIVE: Aberrant subclavian artery (ASA) and Kommerell's diverticulum (KD) are rare vascular anomalies that may be associated with lifestyle-limiting and life-threatening complications. The aim of this study is to report contemporary outcomes after invasive treatment of ASA/KD using a large international dataset. METHODS: Patients who underwent treatment for ASA/KD (2000-2020) were identified through the Vascular Low Frequency Disease Consortium, a multi-institutional collaboration to investigate uncommon vascular disorders. We report the early and mid-term clinical outcomes including stroke and mortality, technical success, and other operative outcomes including reintervention rates, patency, and endoleak. RESULTS: Overall, 285 patients were identified during the study period. The mean patient age was 57 years; 47% were female and 68% presented with symptoms. A right-sided arch was present in 23%. The mean KD diameter was 47.4 mm (range, 13.0-108.0 mm). The most common indication for treatment was symptoms (59%), followed by aneurysm size (38%). The most common symptom reported was dysphagia (44%). A ruptured KD was treated in 4.2% of cases, with a mean diameter of 43.9 mm (range, 18.0-100.0 mm). An open procedure was performed in 101 cases (36%); the most common approach was ASA ligation with subclavian transposition. An endovascular or hybrid approach was performed in 184 patients (64%); the most common approach was thoracic endograft and carotid-subclavian bypass. A staged operative strategy was employed more often than single setting repair (55% vs 45%). Compared with endovascular or hybrid approach, those in the open procedure group were more likely to be younger (49 years vs 61 years; P < .0001), female (64% vs 36%; P < .0001), and symptomatic (85% vs 59%; P < .0001). Complete or partial symptomatic relief at 1 year after intervention was 82.6%. There was no association between modality of treatment and symptom relief (open 87.2% vs endovascular or hybrid approach 78.9%; P = .13). After the intervention, 11 subclavian occlusions (4.5%) occurred; 3 were successfully thrombectomized resulting in a primary and secondary patency of 95% and 96%, respectively, at a median follow-up of 39 months. Among the 33 reinterventions (12%), the majority were performed for endoleak (36%), and more reinterventions occurred in the endovascular or hybrid approach than open procedure group (15% vs 6%; P = .02). The overall survival rate was 87.3% at a median follow-up of 41 months. The 30-day stroke and death rates were 4.2% and 4.9%, respectively. Urgent or emergent presentation was independently associated with increased risk of 30-day mortality (odds ratio [OR], 19.8; 95% confidence interval [CI], 3.3-116.6), overall mortality (OR, 3.6; 95% CI, 1.2-11.2) and intraoperative complications (OR, 8.3; 95% CI, 2.8-25.1). Females had a higher risk of reintervention (OR, 2.6; 95% CI, 1.0-6.5). At an aneurysm size of 44.4 mm, receiver operator characteristic curve analysis suggested that 60% of patients would have symptoms. CONCLUSIONS: Treatment of ASA/KD can be performed safely with low rates of mortality, stroke and reintervention and high rates of symptomatic relief, regardless of the repair strategy. Symptomatic and urgent operations were associated with worse outcomes in general, and female gender was associated with a higher likelihood of reintervention. Given the worse overall outcomes when symptomatic and the inherent risk of rupture, consideration of repair at 40 mm is reasonable in most patients. ASA/KD can be repaired in asymptomatic patients with excellent outcomes and young healthy patients may be considered better candidates for open approaches versus endovascular or hybrid modalities, given the lower likelihood of reintervention and lower early mortality rate.

Midterm Clinical Outcomes of Retrograde Open Mesenteric Stenting for Mesenteric Ischemia.

BACKGROUND: Retrograde open mesenteric stenting (ROMS) has become a mainstay in treatment of mesenteric ischemia; however, follow-up in contemporary studies is limited. METHODS: A single-center retrospective review of patients undergoing ROMS from 2007 to 2020 was conducted. Demographics, presentation, and procedural details were reviewed. End points were morbidity and mortality, technical success, primary patency, reinterventions, and freedom from clinical recurrence. RESULTS: ROMS was performed in 34 patients, 19 female (56%). Mean age was 71 ± 10 years. Eighteen patients (53%) presented with acute mesenteric ischemia (AMI), 11 (32%) with acute-on-chronic, and 5 (15%) with chronic mesenteric ischemia. Etiology was chronic atherosclerosis with/without in-situ thrombosis in 28 patients (82%), superior mesenteric artery dissection in 3, and 1 each with embolic, vasculitic, and nonocclusive ischemia. Four patients (12%) had prior mesenteric procedures (3 Celiac/1 superior mesenteric artery stent) and 1 had unsuccessful transbrachial stenting attempt. Technical success, defined as successful stenting through a retrograde approach was attained in 31 patients (91%), with the 3 remaining patients treated with transbrachial stenting in 2 and iliomesenteric bypass in 1. Covered stents were used in 21 patients (64%) with or without stent extension with bare-metal stents. Eight patients (23%) required thromboembolectomy and 9 (26%) underwent patch angioplasty. Thirty-day mortality rate was 35%, all in patients with AMI (10) or acute-on-chronic (2). Eighteen patients (53%) underwent bowel resection, all presenting acutely. Early reinterventions within the first 30 days were required in 5 patients (15%), including 2 redo ROMS with thrombectomy and endarterectomy, 2 percutaneous stent extensions, and 1 aortic septum fenestration with coiling of a jejunal branch pseudoaneurysm. With a median follow-up of 3.7 (interquartile range: 0.8-5.0) years, in patients surviving discharge, 5 required reintervention yielding freedom from reintervention rates of 87% at 1 year and 71% at 3 years. All postdischarge reinterventions were endovascular with no conversion to bypass. The overall 1-year and 3-year primary patency rates were 70% and 61% (primary-assisted patency at 1 and 3 years was 87% and secondary patency at 1 and 3 years was 97%). The freedom from symptom recurrence was 95% at 1 and 3 years. CONCLUSIONS: ROMS carries high rates of technical success in patients with mesenteric ischemia, despite a high chronic atherosclerotic burden. Although mid-term patency rates are acceptable, AMI is still associated with high early morbidity and mortality, with high rates of associated bowel resection. ROMS is a valuable tool in the armamentarium of vascular surgeons.

Cryopreserved Arterial Allografts Versus Rifampin-Soaked Dacron for the Treatment of Infected Aortic and Iliac Aneurysms.

BACKGROUND: Infected aortic and iliac artery aneurysms are challenging to treat. Cryopreserved arterial allografts (CAAs) or rifampin-soaked Dacron (RSD) are standard options for in situ reconstruction. Our aim was to compare the safety and effectiveness of CAA versus RSD for these complex pathologies. METHODS: This is a retrospective review of infected iliac, abdominal, and thoracoabdominal aortic aneurysms treated with either CAAs or RSD between 2002 and 2022 at our institution. The diagnosis was confirmed by intraoperative, radiologic, or microbiological evidence of aortic infection. Perioperative events, 30-day and long-term mortality, reinfection, and reintervention were analyzed. RESULTS: Thirty patients (17 CAA, 13 RSD) with a mean age of 61 and 68 years, respectively, were identified. The infected aneurysm was most commonly suprarenal or infrarenal. Culture-negative infections were present in 47% of the CAA group and 54% in the RSD group. Early major morbidity was 57% and 54% for the CAA and RSD, respectively. Thirty-day mortality was similar between groups (18% vs. 23% CAA vs. RSD, P ≥ 0.99). Median follow-up was longer in the RSD group (14.5 months vs. 13 months). Overall survival at 1 and 5 years was 80.8% and 64.8% in the CAA group and 69.2% and 57.7% in the RSD group. Reinterventions only occurred with CAA repairs and indications included graft occlusion (2), multiple pseudoaneurysms and reinfection (1), and hemorrhagic shock caused by graft rupture (1). Freedom from reintervention at 1 and 3 years was 87.5% and 79.5% (CAA group) versus 100% and 100% (RSD, P = 0.06). Freedom from reinfection at 1 year was 100% in both groups, while at 3 years it was 90.9% for the CAA group and 100% for the RSD group (P = 0.39). CONCLUSIONS: Infected aortic and iliac aneurysms have high early morbidity and mortality. CAA and RSD had similar outcomes in our series; CAA trended toward higher reintervention rates. Both remain viable options for complex scenarios but require close surveillance.

The USMLE® STEP 1 Pass or Fail Era of the Vascular Surgery Residency Application Process: Implications for Structural Bias and Recommendations.

United States Medical Licensing Examination® (USMLE®) STEP 1 score reporting has been changed to a binary pass/fail format since January 26, 2022. The motives behind this change were (1) the questionable validity of using USMLE STEP 1 as a screening tool during the candidate selection process and (2) the negative impact of using standardized examination scores as an initial gatekeeping threshold for the underrepresented in medicine (URiM) candidates applying to graduate medical education programs, given their generally lower mean standardized exams scores compared to non-URiM students. The USMLE administrators justified this change as a tactic to enhance the overall educational experience for all students and to increase the representation of URiM groups. Moreover, they advised the program directors (PDs) to give more attention to other important qualities and components such as the applicant's personality traits, leadership roles and other extracurricular accomplishments, as part of a holistic evaluation strategy. At this early stage, it is unclear how this change will impact Vascular Surgery Integrated residency (VSIR) programs. Several questions are outstanding, most importantly, how VSIR PDs will evaluate applicants absent the variable which heretofore was the primary screening tool. Our previously published survey showed that VSIR PDs will move their attention to other measures such as USMLE STEP 2 Clinical Knowledge (CK) and letters of recommendation during the VSIR selection process. Furthermore, more emphasis on subjective measures such as the applicant's medical school rank and extracurricular student activities is expected. Given the expected higher weight of USMLE STEP 2CK in the selection process than ever, many anticipate that medical students will dedicate more of their limited time to its preparation at the expense of both clinical and nonclinical activities. Potentially leaving less time to explore specialty pathways and to determine whether Vascular Surgeons  is the appropriate career for them. The critical juncture in the VSIR candidate evaluation paradigm presents an opportunity to thoughtfully transform the process via current (Standardized Letter of Recommendation, USMLE STEP 2CK, and clinical research) and future (Emotional Intelligence, Structure Interview and Personality Assessment) measures which constitute a framework to follow in the USMLE STEP 1 pass/fail era.

International Multi-Institutional Experience with Presentation and Management of Aortic Arch Laterality in Aberrant Subclavian Artery and Kommerell's Diverticulum.

BACKGROUND: Aberrant subclavian artery (ASA) with or without Kommerell's diverticulum (KD) is a rare anatomic aortic arch anomaly that can cause dysphagia and/or life-threatening rupture. The objective of this study is to compare outcomes of ASA/KD repair in patients with a left versus right aortic arch. METHODS: Using the Vascular Low Frequency Disease Consortium methodology, a retrospective review was performed of patients ≥18 years old with surgical treatment of ASA/KD from 2000 to 2020 at 20 institutions. RESULTS: 288 patients with ASA with or without KD were identified; 222 left-sided aortic arch (LAA), and 66 right-sided aortic arch (RAA). Mean age at repair was younger in LAA 54 vs. 58 years (P = 0.06). Patients in RAA were more likely to undergo repair due to symptoms (72.7% vs. 55.9%, P = 0.01), and more likely to present with dysphagia (57.6% vs. 39.1%, P < 0.01). The hybrid open/endovascular approach was the most common repair type in both groups. Rates of intraoperative complications, death within 30 days, return to the operating room, symptom relief and endoleaks were not significantly different. For patients with symptom status follow-up data, in LAA, 61.7% had complete relief, 34.0% had partial relief and 4.3% had no change. In RAA, 60.7% had complete relief, 34.4% had partial relief and 4.9% had no change. CONCLUSIONS: In patients with ASA/KD, RAA patients were less common than LAA, presented more frequently with dysphagia, had symptoms as an indication for intervention, and underwent treatment at a younger age. Open, endovascular and hybrid repair approaches appear equally effective, regardless of arch laterality.

Thirty-year single-center experience with arterial thoracic outlet syndrome.

OBJECTIVE: Arterial thoracic outlet syndrome (ATOS) is rare. We present our 30-year experience with the management of ATOS at a high-volume referral center. METHODS: A retrospective review of all patients who had undergone primary operative treatment for ATOS from 1988 to 2018 was performed. ATOS was defined as subclavian artery pathology caused by extrinsic compression from a bony abnormality within the thoracic outlet. RESULTS: A total of 41 patients (45 limbs) underwent surgery for ATOS at a median age of 46 years (interquartile range [IQR], 34-58 years). Chronic symptoms (>6 weeks) were present in 31 limbs (69%). Of the 45 limbs, 13 (29%) presented with acute limb ischemia (ALI), requiring urgent brachial artery thromboembolectomy (BAT) in 9 and catheter-directed thrombolysis and thrombectomy (CDT) in 4. All patients underwent thoracic outlet decompression. 31 limbs (69%) required subclavian artery reconstruction. No perioperative deaths and only one major adverse limb event occurred. Patients with ALI underwent staged thoracic outlet decompression after initial BAT or CDT at a median of 23 days (IQR, 11-140 days). Of the 13 limbs with an initial presentation of ALI, 8 (62%) had recurrent thromboembolic events before thoracic outlet decompression subsequently requiring 10 additional BATs and 1 CDT. The cumulative probability of recurrent embolization at 14, 30, and 90 days was 8.33% (95% confidence interval [CI], 1.28%-54.42%), 16.67% (95% CI, 4.70%-59.06%), and 33.33% (95% CI, 14.98-74.20%), respectively. The median follow-up for 32 patients (35 limbs) was 13 months (IQR, 5-36 months). Subclavian artery/graft primary and secondary patency was 87% and 90%, respectively, at 5 years by Kaplan-Meier analysis. Of the 35 limbs, 5 (14%) had chronic upper extremity pain and 5 (14%) had persistent weakness. Preoperative forearm or hand pain and brachial artery occlusion were associated with chronic pain (P = .04 and P = .03) and weakness (P = .03 and P = .02). Of the 13 limbs that presented with ALI, 11 had a median follow-up after thoracic outlet decompression of 6 months (IQR, 5-14 months), including 9 (82%) with oral anticoagulation therapy. Anticoagulation therapy had no effect on subclavian artery patency (P = 1.0) or the presence of chronic symptoms (P = .93). CONCLUSIONS: The presentation of ATOS is diverse, and the diagnosis can be delayed. Preoperative upper extremity pain and brachial artery occlusion in the setting of ALI were associated with chronic pain and weakness after thoracic outlet decompression. Delayed thoracic outlet decompression was associated with an increased risk of recurrent thromboembolic events for patients who presented with ALI. An early and accurate diagnosis of ATOS is necessary to reduce morbidity and optimize outcomes.

Outcomes of balloon-expandable versus self-expandable stent graft for endovascular repair of iliac aneurysms using iliac branch endoprosthesis.

PURPOSE: The purpose of this study was to compare outcomes of internal iliac artery (IIA) stenting using balloon-expandable (BESG) or self-expandable stent grafts (SESG) during endovascular repair of aortoiliac aneurysms with iliac branch endoprosthesis (IBE; W. L. Gore, Flagstaff, Ariz). METHODS: We retrospectively reviewed all consecutive patients treated for aortoiliac aneurysms using IBE between 2014 and 2020. IIA stenting was performed using either the IIA side branch SESG or a Gore VBX BESG (W. L. Gore). Indications for use of BESGs were "up-and-over" IBE technique for type IB endoleak after prior endovascular aortic aneurysm repair (EVAR), short IIA length, and need for IIA extension into divisional branches (outside instructions for use). End points included technical success, freedom from buttock claudication, primary IIA patency, and freedom from IIA branch instability (eg, branch-related death or rupture, occlusion, disconnection, or reintervention for stenosis, kink, or endoleak), freedom from type IC/IIIC endoleak, and freedom from secondary interventions. RESULTS: There were 90 patients (86 males and 4 females) with a mean age of 74 ± 7 years treated by EVAR with 108 IBEs. Choice of stent was BESG in 43 and SESG in 65 targeted IIAs. BESGs were used more frequently in patients with prior EVAR (22% vs 2%; P = .003,), isolated IBEs (31% vs 2%; P < .001), and in patients with IIA aneurysms requiring stenting into divisional branches (36% vs 5%; P < .001). Technical success was similar for BESGs and SESGs (97% vs 100%; P = .40), respectively. The mean follow-up was 25 ± 16 months (range, 11-34 months). At 2 years, freedom from buttock claudication was 100% for BESG and 95 ± 3% for SESG (Log-rank 0.26), with no difference in primary patency (BESG, 100% vs SESG, 94 ± 4%; Log-rank 0.94). There were four (9%) IIA-related endoleaks in the BESG group and one (2%) in the SESG group (P = .08). Freedom from IIA branch instability was 87 ± 6% for BESG and 96 ± 3% for SESG at 2 years (Log-rank 0.043). Freedom from type IC/IIIC endoleak was 87 ± 7% for BESG and 98 ± 2% for SESG at the same interval (Log-rank 0.06). There was no difference in freedom from reinterventions for BESG and SESG (92 ± 6% vs 98 ± 2%; Log-rank 0.34), respectively. CONCLUSIONS: BESGs were used more frequently during IBE procedures indicated for failed EVAR, isolated common iliac aneurysms, and IIA aneurysms requiring extension into divisional branches. Despite these differences and BESG being used outside instructions for use, both stent types had similar primary patency, freedom from buttock claudication, and freedom from reinterventions. However, BESGs were associated with higher rates of IIA-related branch instability.

Aneurysms of the superior mesenteric artery and its branches.

OBJECTIVE: Aneurysms of the superior mesenteric artery (SMA) and its branches are rare and account for only 6% to 15% of all visceral artery aneurysms. In the present report, we have described our 30-year experience with the management of aneurysms of the SMA and its branches at a high-volume referral center. METHODS: A retrospective review of all patients with a diagnosis of an aneurysm of the SMA or one of its branches from 1988 to 2018 was performed. Pseudoaneurysms and mycotic aneurysms were excluded. The clinical presentation, etiology, aneurysm shape and size, treatment modalities, and outcomes were analyzed. The growth rate of the aneurysms was estimated using linear regression. RESULTS: A total of 131 patients with 144 aneurysms were reviewed. The patients were primarily men (64%), with a median age of 60 years. Of the 144 aneurysms, 57 were fusiform, 30 were saccular, and 57 were dissection-associated aneurysms. Of the 131 patients, 41 had had an isolated SMA branch aneurysm. Degenerative aneurysms were the most common etiology (66%). A total of 35 patients (27%) were symptomatic at presentation. Of the 144 aneurysms, 111 had multiple computed tomography angiograms available, with a median follow-up of 43.6 months (interquartile range, 10.6-87.2 months). Only 18 aneurysms (16%) had had an estimated growth rate of ≥1.0 mm/y. The initial aneurysm size was significantly associated with the growth rate for the fusiform aneurysms (odds ratio [OR], 1.13; 95% confidence interval [CI], 1.0-1.3]; P = .02) but not for the saccular (OR, 0.91; 95% CI, 0.76-1.1; P = 1.1) or dissection-associated (OR, 1.2; 95% CI, 0.91-1.5; P = .20) aneurysms. Acute abdominal pain (OR, 5.9; 95% CI, 1.6-22; P = .01) and chronic abdominal pain (OR, 3.7; 95% CI, 1.1-13; P = .04) were associated with aneurysm growth. Only two patients had a ruptured aneurysm, both of whom presented with rupture with no prior imaging studies. These two patients had a diagnosis of fibromuscular dysplasia and systemic lupus erythematosus, respectively. Of the 131 patients, 46 (34%) had undergone operative repair, including 36 open revascularizations and 8 endovascular procedures. The average aneurysm size for these 46 patients was 24.0 ± 8.6 mm. One patient died perioperatively, and nine patients experienced perioperative complications (25%). Of the 144 aneurysms, 91 were <20 mm, with an average size of 13.4 ± 3.1 mm. These 91 aneurysms had been followed up for a median of 120.8 months (interquartile range, 30.5-232.2 months), with no ruptures within this cohort during the follow-up period. CONCLUSIONS: The present study represents one of the largest series on aneurysms of the SMA and its branches. Our results showed that aneurysms of the SMA are relatively stable. Patients with symptomatic and fusiform aneurysms had a greater risk of growth. Aneurysms <20 mm with a degenerative etiology can be safely monitored without treatment.

Patency rates of hepatic arterial resection and revascularization in locally advanced pancreatic cancer.

BACKGROUND: Arterial resection (AR) for pancreatic adenocarcinoma is increasingly considered at specialized centers. We aimed to examine the incidence, risk factors, and outcomes of hepatic artery (HA) occlusion after revascularization. METHODS: We included patients undergoing HA resection with interposition graft (IG) or primary end-to-end anastomoses (EE). Complete arterial occlusion (CAO) was defined as "early" (EO) or "late" (LO) before/after 90 days respectively. Kaplan-Meier and change-point analysis for CAO was performed. RESULTS: HA resection was performed in 108 patients, IG in 61% (66/108) and EE in 39% (42/108). An equal proportion (50%) underwent HA resection alone or in combination with celiac and/or superior mesenteric artery. CAO was identified in 18% of patients (19/108) with arterial IG least likely to occlude (p=0.019). Hepatic complications occurred in 42% (45/108) and correlated with CAO, symptomatic patients, venous resection, and postoperative portal venous patency. CAO-related operative mortality was 4.6% and significantly higher in EO vs LO (p = 0.046). Median CAO occlusion was 126 days. With change-point analysis, CAO was minimal beyond postoperative day 158. CONCLUSION: CAO can occur in up to 18% of patients and the first 5-month post-operative period is critical for surveillance. LO is associated with better outcomes compared to EO unless there is inadequate portal venous inflow.