Volumetric Analysis of Acute Uncomplicated Type B Aortic Dissection Using an Automated Deep Learning Aortic Zone Segmentation Model.

INTRODUCTION: Machine learning techniques have shown excellent performance in 3D medical image analysis, but have not been applied to acute uncomplicated type B aortic dissection (auTBAD) utilizing SVS/STS-defined aortic zones. The purpose of this study was to establish a trained, automatic machine learning aortic zone segmentation model to facilitate performance of an aortic zone volumetric comparison between auTBAD patients based on rate of aortic growth. METHODS: Patients with auTBAD and serial imaging were identified. For each patient, imaging characteristics from two CT scans were analyzed: (1) the baseline CTA at index admission, and (2) either the most recent surveillance CTA, or the most recent CTA prior to an aortic intervention. Patients were stratified into two comparative groups based on aortic growth: rapid growth (diameter increase ≥5mm/year) and no/slow growth (diameter increase <5mm/year). Deidentified images were imported into an open-source software package for medical image analysis and images were annotated based on SVS/STS criteria for aortic zones. Our model was trained using 4-fold cross-validation. The segmentation output was used to calculate aortic zone volumes from each imaging study. RESULTS: Of 59 patients identified for inclusion, rapid growth was observed in 33 (56%) patients and no/slow growth was observed in 26 (44%) patients. There were no differences in baseline demographics, comorbidities, admission mean arterial pressure, number of discharge antihypertensives, or high-risk imaging characteristics between groups (p>0.05 for all). Median duration between baseline and interval CT was 1.07 years (IQR 0.38-2.57). Post-discharge aortic intervention was performed in 13 (22%) of patients at a mean of 1.5±1.2 years, with no difference between groups (p>0.05). Among all patients, the largest relative percent increases in zone volumes over time were found in zone 4 (13.9% IQR -6.82-35.1) and zone 5 (13.4% IQR -7.78-37.9). There were no differences in baseline zone volumes between groups (p>0.05 for all). Average Dice coefficient, a performance measure of the model output, was 0.73. Performance was best in zone 5 (0.84) and zone 9 (0.91). CONCLUSIONS: We describe an automatic deep learning segmentation model incorporating SVS-defined aortic zones. The open-source, trained model demonstrates concordance to the manually segmented aortas with the strongest performance in zones 5 and 9, providing a framework for further clinical applications. In our limited sample, there were no differences in baseline aortic zone volumes between rapid growth and no/slow growth patients.

Perioperative Cerebrospinal Fluid Drain Placement Does Not Increase Venous Thromboembolism Risk After Thoracic and Fenestrated Endovascular Aortic Repair.

BACKGROUND: Venous thromboembolism (VTE) incidence after thoracic and fenestrated endovascular aortic repair (TEVAR/FEVAR) is high (up to 6-7%) relative to other vascular procedures; however, the etiology for this discrepancy remains unknown. Notably, patients undergoing TEVAR/FEVAR commonly receive cerebrospinal fluid drains (CSFDs) for neuroprotection, requiring interruption of perioperative anticoagulation and prolonged immobility. We hypothesized that CSFDs are a risk factor for VTE after TEVAR/FEVAR. METHODS: Consecutive TEVAR/FEVAR patients at a single center were reviewed (2011-2020). Cerebrospinal fluid drains (CSFDs) were placed based on surgeon preference preoperatively or for spinal cord ischemia (SCI) rescue therapy postoperatively. The primary end-point was VTE occurrence, defined as any new deep venous thrombosis (DVT) or pulmonary embolism (PE) confirmed on imaging within 30 days postoperatively. Routine postoperative VTE screening was not performed. Patients with and without VTE, and subjects with and without CSFDs were compared. Logistic regression was used to explore associations between VTE incidence and CSFD exposure. RESULTS: Eight hundred ninety-seven patients underwent TEVAR/FEVAR and 43% (n = 387) received a CSFD at some point during their care (preoperative: 94% [n = 365/387]; postoperative SCI rescue therapy: 6% [n = 22/387]). CSFD patients were more likely to have previous aortic surgery (44% vs. 37%; P = 0.028) and received more postoperative blood products (780 vs. 405 mL; P = 0.005). The overall VTE incidence was 2.2% (n = 20). 70% (14) patients with VTE had DVT, 50% (10) had PE, and 20% (4) had DVT and PE. Among TEVAR/FEVAR patients with VTE, 65% (n = 13) were symptomatic. Most VTEs (90%, n = 18) were identified inhospital and the median time to diagnosis was 12.5 (interquartile range 7.5-18) days postoperatively. Patients with VTE were more likely to have nonelective surgery (95% vs. 41%; P < 0.001), had higher American Society of Anesthesiologists classification (4.1 vs. 3.7; P < 0.001), required longer intensive care unit admission (24 vs. 12 days; P < 0.001), and received more blood products (1,386 vs. 559 mL; P < 0.001). Venous thromboembolism (VTE) incidence was 1.8% in CSFD patients compared to 3.5% in non-CSFD patients (odds ratio 0.70 [95% confidence interval 0.28-1.78, P = 0.300). However, patients receiving CSFDs postoperatively for SCI rescue therapy had significantly greater VTE incidence (9.1% vs. 1.1%; P = 0.044). CONCLUSIONS: CSFD placement was not associated with an increased risk of VTE in patients undergoing TEVAR/FEVAR. Venous thromboembolism (VTE) risk was greater in patients undergoing nonelective surgery and those with complicated perioperative courses. Venous thromboembolism (VTE) risk was greater in patients receiving therapeutic CSFDs compared to prophylactic CSFDs, highlighting the importance of careful patient selection for prophylactic CSFD placement.

The measurable impact of a diversity, equity, and inclusion editor on diversifying content, authorship, and peer review participation in the Journal of Vascular Surgery.

OBJECTIVE: Women and minorities remain under-represented in academic vascular surgery. This under-representation persists in the editorial peer review process which may contribute to publication bias. In 2020, the Journal of Vascular Surgery (JVS) addressed this by diversifying the editorial board and creating a new Editor of Diversity, Equity, and Inclusion (DEI). The impact of a DEI editor on modifying the output of JVS has not yet been examined. We sought to determine the measurable impact of a DEI editor on diversifying perspectives represented in the journal, and on contributing to changes in the presence of DEI subject matter across published journal content. METHODS: The authorship and content of published primary research articles, editorials, and special articles in JVS were examined from November 2019 through July 2022. Publications were examined for the year prior to initiation of the DEI Editor (pre), the year following (post), and from September 2021 to July 2022, accounting for the average 47-week time period from submission to publication in JVS (lag). Presence of DEI topics and women authorship were compared using χ2 tests. RESULTS: During the period examined, the number of editorials, guidelines, and other special articles dedicated to DEI topics in the vascular surgery workforce or patient population increased from 0 in the year prior to 4 (16.7%) in the 11-month lag period. The number of editorials, guidelines, and other special articles with women as first or senior authors nearly doubled (24% pre, 44.4% lag; P = .31). Invited commentaries and discussions were increasingly written by women as the study period progressed (18.7% pre, 25.9% post, 42.6% lag; P = .007). The number of primary research articles dedicated to DEI topics increased (5.6% pre, 3.3% post, 8.1% lag; P = .007). Primary research articles written on DEI topics were more likely to have women first or senior authors than non-DEI specific primary research articles (68.0% of all DEI vs 37.5% of a random sampling of non-DEI primary research articles; P < .001). The proportion of distinguished peer reviewers increased (from 2.8% in 2020 to 21.9% in 2021; P < .001). CONCLUSIONS: The addition of a DEI editor to JVS significantly impacted the diversification of topics, authorship of editorials, special articles, and invited commentaries, as well as peer review participation. Ongoing efforts are needed to diversify subject matter and perspective in the vascular surgery literature and decrease publication bias.

National Institutes of Health funding among vascular surgeons is rare.

BACKGROUND: The National Institutes of Health (NIH) is an essential source of funding for vascular surgeons conducting research. NIH funding is frequently used to benchmark institutional and individual research productivity, help determine eligibility for academic promotion, and as a measure of scientific quality. We sought to appraise the current scope of NIH funding to vascular surgeons by appraising the characteristics of NIH-funded investigators and projects. In addition, we also sought to determine whether funded grants addressed recent Society for Vascular Surgery (SVS) research priorities. METHODS: In April 2022, we queried the NIH Research Portfolio Online Reporting Tools Expenditures and Results (RePORTER) database for active projects. We only included projects that had a vascular surgeon as a principal investigator. Grant characteristics were extracted from the NIH Research Portfolio Online Reporting Tools Expenditures and Results database. Principal investigator demographics and academic background information were identified by searching institution profiles. RESULTS: There were 55 active NIH awards given to 41 vascular surgeons. Only 1% (41/4037) of all vascular surgeons in the United States receive NIH funding. Funded vascular surgeons are an average of 16.3 years out of training; 37% (n = 15) are women. The majority of awards (58%; n = 32) were R01 grants. Among the active NIH-funded projects, 75% (n = 41) are basic or translational research projects, and 25% (n = 14) are clinical or health services research projects. Abdominal aortic aneurysm and peripheral arterial disease are the most commonly funded disease areas and together accounted for 54% (n = 30) of projects. Three SVS research priorities are not addressed by any of the current NIH-funded projects. CONCLUSIONS: NIH funding of vascular surgeons is rare and predominantly consists of basic or translational science projects focused on abdominal aortic aneurysm and peripheral arterial disease research. Women are well-represented among funded vascular surgeons. Although the majority of SVS research priorities receive NIH funding, three SVS research priorities are yet to be addressed by NIH-funded projects. Future efforts should focus on increasing the number of vascular surgeons receiving NIH grants and ensuring all SVS research priorities receive NIH funding.

Presentation and Outcomes of Elective and Nonelective Complex Endovascular Repair for Thoracoabdominal and Juxtarenal Aortic Aneurysms.

BACKGROUND: Endovascular repair of thoracoabdominal aortic aneurysms (TAAA) and juxtarenal aortic aneurysms (JAA) with fenestrated and/or branched endografts (B/FEVAR) has become common. Physician modified endografts for patients presenting with symptomatic or contained ruptures has made B/FEVAR a feasible option in nonelective settings. The purpose of this study was to describe our 10-year institutional experience with endovascular interventions for TAAA in elective and nonelective cases to evaluate differences in outcomes and the clinical risk factors associated with nonelective presentation. METHODS: A prospectively maintained database was retrospectively queried for patients undergoing B/FEVAR for TAAA and JAA at a single tertiary care academic institution between 1/2011 and 12/2020. Data collected included demographics, comorbidities, presenting symptoms, aneurysm characteristics, and clinical outcomes. Nonelective repair was defined as any patient that presented through the Emergency Department, as a hospital transfer, or as a direct admission from clinic and had aortic repair performed during the same admission. Univariate analyses were used to compare patients. The primary outcomes were 30-day and 1-year mortality. Secondary outcomes included perioperative complications and nonhome discharge. RESULTS: Between 1/201 and 12/2020, a total of 208 patients underwent B/FEVAR for TAAA (173) and JAA (35). Nonelective repair was performed in 44 (21%) patients with 39 for TAAA (23%) and 5 for JAA (14%). Nonelective patients were younger (71 ± 11 vs. 74 ± 7 years, P = 0.03), more likely to be self-pay or have Medicaid (11% vs. 2%, P = 0.02) and had a different race distribution compared to the elective cohort (P < 0.01). Thirty-day mortality was 4% (n = 6) in elective repairs and 7% (n = 3) in nonelective repairs. One-year mortality was 13% (n = 22) in elective repairs and 18% (n = 8) in nonelective repairs. There were no differences between patients receiving elective versus nonelective repair in 30-day (P = 0.40) or 1-year mortality (P = 0.47). Nonelective patients had longer median duration of stay (11 interquartile range (IQR) 6-15 vs. 5 IQR 4-8, P < 0.01), postoperative length of stay (7 IQR 5-12 vs. 4 IQR 3-7, P < 0.01), and more intensive care unit days (6 IQR 3-8 vs. 3 IQR 2-5, P < 0.01). There were no differences in other secondary outcomes between elective and nonelective patients including inpatient and access-related complications, re-interventions, and nonhome discharge (P > 0.05 for all comparisons). A composite "any complication" occurred more frequently in patients with nonelective repair (50% vs. 35%, P = 0.03). CONCLUSIONS: Endovascular repair for TAAA or JAA is a good option in patients undergoing nonelective surgical intervention, with comparable 30-day mortality, 1-year mortality, and perioperative morbidity to that of patients undergoing elective B/FEVAR.

Outcomes of endovascular abdominal aortic aneurysm repair conversion in octogenarians treated at a high-volume aorta center.

BACKGROUND: Endovascular abdominal aortic aneurysm repair (EVAR) has become the dominant treatment strategy for infrarenal abdominal aortic aneurysms but has been especially preferred for octogenarian (age ≥80 years) patients because of concerns surrounding comorbidity severity and physiologic frailty. However, EVAR failure resulting in subsequent open conversion (EVAR-c) has been increasingly reported in older patients, although a paucity of literature focusing on the outcomes in this subgroup is available. The purpose of the present analysis was to evaluate our experience with EVAR-c for octogenarians (age ≥80 years) compared with that for younger patients (age <80 years). METHODS: A retrospective review of all nonmycotic EVAR-c procedures (2002-2020) at a single high-volume academic hospital with a dedicated aorta center (available at: https://www.uf-health-aortic-disease-center) was performed. A total of 162 patients were categorized into octogenarian (age ≥80 years; n = 43) and nonoctogenarian (age <80 years; n = 119) cohorts and compared. The primary end point was 30-day mortality. The secondary end points included complications, 90-day mortality, and overall survival. Cox regression was used to determine the effects of selected covariates on mortality risk. The Kaplan-Meier method was used to estimate survival. RESULTS: No differences in the preadmission EVAR reintervention rates were present (octogenarians, 42%; nonoctogenarians, 43%; P = 1.00) although the interval to the first reintervention was longer for the octogenarians (41 months) than for the nonoctogenarians (15 months; P = .01). In addition, the time to EVAR-c was significantly longer for the octogenarian patients (61 months) than for the nonoctogenarian patients (39 months; P < .01). No difference in rupture presentation was evident (14% vs 10%; P = .6). However, elective EVAR-c occurred less frequently for octogenarians (42%) than for nonoctogenarians (59%; P = .07). The abdominal aortic aneurysm diameter was significantly larger for elective octogenarian EVAR-c (7.8 ± 1.9 cm) than for nonoctogenarian EVAR-c (7.0 ± 1.5 cm; P = .02), and the presence of a type Ia endoleak was the most common indication overall (58%; n = 91). A trend toward greater 30-day mortality was evident for octogenarian patients (16%) compared with nonoctogenarian patients (7%; P = .06). Similarly, the 90-day mortality was greater for the octogenarian patients (26%) than for the nonoctogenarian patients (10%; P = .02). However, the incidence of any complication (56% vs 49%; P = .5), readmission rate (12% vs 6%; P = .3), unplanned reoperation rate (10% vs 5%; P = .5), and length of stay (11 days vs 9 days; P = .3) were not significantly different between the two groups. Age ≥80 years was predictive of short-term mortality after nonelective but not after elective surgery. However, increasing comorbidities, nonelective admission, and renal or mesenteric revascularization showed the strongest association with mortality risk. Survival at 1 and 3 years was not different between the two groups when comparing all patients after the first 90 days postoperatively. CONCLUSIONS: Although the unadjusted perioperative mortality was greater for octogenarian patients, the risk-adjusted elective outcomes were comparable to those for younger EVAR-c patients when treated at a high-volume aortic surgery center. This finding underscores the importance of appropriate patient selection and modulation of operative complexity when feasible to achieve optimal results. Providers caring for octogenarian patients with EVAR failure should consider timely elective referral to high-volume aorta centers to reduce resource usage and the frequency of nonelective presentations.

Non-guideline-compliant endovascular abdominal aortic aneurysm repair in women is associated with increased mortality and reintervention compared with men.

OBJECTIVE: Sex-based disparities in surgical outcomes have emerged as an important focus in contemporary healthcare delivery. Likewise, the appropriate usage of endovascular abdominal aortic aneurysm repair (EVAR) in the United States remains a subject of ongoing controversy, with a significant number of U.S. EVARs failing to adhere to the Society for Vascular Surgery (SVS) clinical practice guideline (CPG) diameter thresholds. The purpose of the present study was to determine the effect of sex among patients undergoing EVAR that was not compliant with the SVS CPGs. METHODS: All elective EVAR procedures for abdominal aortic aneurysms without a concomitant iliac aneurysm (≥3.0 cm) in the SVS Vascular Quality Initiative were analyzed (2015-2019; n = 25,112). SVS CPG noncompliant repairs were defined as a size of <5.5 cm for men and <5.0 cm for women. The primary endpoint was 30-day mortality. The secondary endpoints were all-cause mortality, complications, and reintervention. Logistic regression was performed to control for surgeon- and patient-level factors. Freedom from the endpoints was determined using the Kaplan-Meier method. RESULTS: Noncompliant EVAR was performed in 9675 patients (38.5%). Although men were significantly more likely to undergo such procedures (90% vs 10%; odds ratio [OR], 3.1; 95% confidence interval [CI], 2.9-3.4; P < .0001), the 30-day mortality was greater for the women than the men (1.8% vs 0.5%; P = .0003). Women also experienced significantly higher rates of multiple complications, including postoperative myocardial infarction (1% vs 0.3%; P = .006), respiratory failure (1.4% vs 0.6%; P = .01), intestinal ischemia (0.7% vs 0.2%; P = .003), access vessel hematoma (3% vs 1.2%; P = .0006), and iliac access vessel injury (2.4% vs 0.8%; P < .0001). Additionally, women experienced increased overall 1-year reintervention rates (11.5% vs 5.8%; P < .0001). In the adjusted analysis, 30-day mortality and any in-hospital complication risk remained significantly greater for the women (30-day death: OR, 3.1; 95% CI, 1.6-5.8; P = .0005; in-hospital complication: OR, 1.9; 95% CI, 1.4-2.6; P < .0001). Women also experienced increased reintervention rates over time compared with men (OR, 1.5; 95% CI, 1.1-2.2; P = .02). CONCLUSIONS: Although men were more likely to undergo non-CPG compliant EVAR, women experienced increased short-term morbidity and 30-day mortality and higher rates of reintervention when undergoing non-CPG compliant EVAR. These unanticipated findings necessitate increased scrutiny of current U.S. sex-based EVAR practice and should caution against the use of non-CPG compliant EVAR for women.

Improved perioperative mortality after secondary aortoenteric fistula repair and lessons learned from a 20-year experience.

BACKGROUND: Secondary aortoenteric fistulas (SAEFs) are rare but represent one of the most challenging and devastating problems for vascular surgeons. Several issues surrounding SAEF treatment remain unresolved, including optimal surgical reconstruction and conduit choice. We performed an audit of our experience with SAEFs and highlight aspects of care that have affected outcomes over time with the intent to identify factors associated with best outcomes. METHODS: We performed a single center, retrospective review of all consecutive SAEF repairs (1999-2019), defined as presence of a false communication between an enteric structure and pre-existing aortic graft. The primary endpoint was 30-day mortality. Secondary endpoints included incidence of complications and overall survival. Time-dependent outcome comparison was performed. Cox proportional hazards modeling and life-table analysis estimated risk and freedom from endpoints. RESULTS: A total of 57 patients (63% male; n = 36) presented with SAEF (median age, 69 years; interquartile range [IQR], 61-74 years). Median follow-up time was 10 months (interquartile range, 3-21 months. The most common presenting symptoms were gastrointestinal bleeding (60%; n = 34) and abdominal pain (56%; n= 3 2). For the overall cohort, 30% (n = 17) underwent extra-anatomic bypass with aortic ligation, 30% (n = 17) rifampin-soaked Dacron graft, 26% (n = 15) femoral vein (eg, neoaortoiliac system), and 14% (n = 8) cryopreserved aortic allograft. The enteric communication involved the duodenum in 85% (n = 48), and a double-layer hand-sewn primary repair was most commonly employed (61%; n = 35). Thirty-day mortality was 35% (n = 20) with no significant difference between 90 days (39%; n = 22) and 180 days (42%; n = 24). Morbidity was 70% (n = 40), with gastrointestinal (30%; n = 17; leak [9%]), pulmonary (25%; n = 14), and renal (21%) complications being most common. Incidence of reoperation for any vascular and/or gastrointestinal-related complication was 56% (n = 32). One-year and 3-year survival was 54% ± 6% and 48% ± 8%, respectively. Over time, 30- and 90-day mortality improved (odds ratio, 0.1; 95% confidence interval, 0.4-0.5; P = .002) despite no change in patient factors, operative strategy, conduit choice, or morbidity rate. Prehospital history of gastrointestinal bleeding was associated with worse survival (hazard ratio, 2.0; 95% confidence interval, 1.0-3.9; P = .06); however, reconstruction strategy (in-situ vs extra-anatomic bypass), postoperative gastrointestinal and/or vascular complication, omental flap use, and preoperative endovascular aneurysm repair history were not associated with outcome. CONCLUSIONS: In conclusion, we observed improved short-term mortality despite no significant change in patient presentation or postoperative complications. This highlights increasing institutional experience in selecting the optimal surgical strategy and improved ability to rescue patients experiencing adverse postoperative events. An individualized approach to reconstruction and conduit choice can lead to best outcomes after SAEF management when patients are treated at a high-volume aortic surgery center.

Center volume is associated with diminished failure to rescue and improved outcomes following elective open abdominal aortic aneurysm repair.

OBJECTIVE: Conflicting annual procedure volumes have been endorsed among different watchdog groups and professional societies, obscuring credentialing paradigms. There has been ample focus on surgeon volume to date but less attention on the effect of center volume. Specifically, whether center volume might be a better proxy for high-quality care. In the present study, we aimed to measure the association of center volume on open abdominal aortic aneurysm (AAA) repair (OAR) outcomes and failure to rescue (FTR). METHODS: All elective OARs (2003-2020) in the Society for Vascular Surgery Vascular Quality Initiative were reviewed (n = 9791). FTR was defined as in-hospital death after the occurrence of a complication (ie, cardiac, stroke, pulmonary, renal, colonic ischemia, return to the operating room for bleeding). The annual center volume for 218 hospitals was calculated, and the volume quartiles (quartile 1 [Q1], ≤3 procedures/y; quartile 2 [Q2], 4-6 procedures/y; quartile 3 [Q3], 7-10 procedures/y; quartile 4 [Q4], >10 procedures/y) were derived for comparison. Logistic regression was used to estimate the effect of center volume and determine the predictors of FTR. RESULTS: The center volume quartiles and incidence of FTR varied significantly (Q4, 2.5% vs Q1 and Q2, 4.9%; P < .0001; overall FTR, 3.1% [n = 302]). The patients were demographically similar among the quartiles. High-volume centers had used epidural anesthesia more often (Q4, 53%; vs Q1, 31%; P < .0001) but were less likely to use thrombectomy (Q4, 5%; vs Q1, 10%; P < .0001) or any concomitant procedure (Q4, 19%; vs Q1, 22%; P = .05). High-volume centers had had lower rates of pulmonary, renal, and overall complications (pulmonary: Q4, 7%; vs Q1-Q2, 8%-11%; renal: Q4, 16%; vs Q1-2, 19%-21%; P < .0001; overall mean number of complications: Q4, 0.46; vs Q1, 0.52; P = .0008). The crude 30-day and 1-year mortality rates were reduced at the higher volume centers (30 days: Q4, 3%; vs Q1-Q2, 6%; P < .0001; 1 year: Q4, 7%; vs Q1-Q2, 10%-11%; P < .0001). A strong inverse relationship between center volume and FTR was identified (P < .0001). In the adjusted analysis, OARs performed in high-volume centers (Q4 vs Q1) had a 50% risk reduction in FTR (odds ratio [OR], 0.48; 95% confidence interval [CI], 0.3-0.8; P = .004). Among the complications, a return to the operating room for bleeding was most likely to result in FTR (OR, 11.8; 95% CI, 4.3-33; P < .0001). A 24-fold increased risk of FTR was found for patients experiencing three or more complications vs one complication (OR, 24; 95% CI, 17-35; P < .0001). CONCLUSIONS: A greater center volume was strongly associated with significantly diminished FTR, reduced complications, and need for surgical adjuncts during OAR. These findings highlight the utility of center volume as an effective proxy to ensure high-quality aneurysm care.

Contemporary incidence, outcomes, and survival associated with endovascular aortic aneurysm repair conversion to open repair among Medicare beneficiaries.

OBJECTIVE: The widespread application of endovascular abdominal aortic aneurysm repair (EVAR) has ushered in an era of requisite postoperative surveillance and the potential need for reintervention. The national prevalence and results of EVAR conversion to open repair, however, remain poorly defined. The purpose of this analysis was to define the incidence of open conversion and its associated outcomes. METHODS: The SVS Vascular Quality Initiative EVAR registry linked to Medicare claims via Vascular Implants Surveillance and Interventional Outcomes Network was queried for open conversions after initial EVAR procedures from 2003 to 2016. Cumulative conversion incidence within up to 5 years after EVAR and outcomes after open intervention were determined. Multivariable logistic regressions were used to identify independent predictors of conversion and mortality. RESULTS: Among 15,937 EVAR patients, 309 (1.9%) underwent an open conversion: 43% (n = 132) early (<30 days) and 57% (n = 177) late (>30 days). The longitudinally observed rate of conversion was constant over time, as well as by geographic region. Independent predictors of conversion included female sex (hazard ratio [HR], 1.49; P < .001), aneurysm diameter or more than 6.0 cm at the time of index EVAR (HR, 1.74; P < .001), nonelective repair (compared with elective presentation: HR, 1.72; P < .001), and aortouni-iliac repairs (HR, 2.19; P < .001). In contrast, adjunctive operative procedures such as endo-anchors or cuff extensions (HR, 0.62; P = .06) were protective against long-term conversion. Both early (HR, 1.6; P < .001) and late (HR, 1.26; P = .07) open conversions were associated with significant 30-day (total cohort, 15%) and 1-year mortality (total cohort, 25%). Patients undergoing open conversion experienced high rates of 30-day readmission (42%) and cardiac (45%), renal (32%), and pulmonary (30%) complications. CONCLUSIONS: This large, registry-based analysis is among the first to document the incidence and outcomes for open conversion after EVAR in a national cohort with long-term follow-up. Importantly, women, patients with large aneurysms, and complex anatomy, as well as urgent or emergent EVARs are at an increased risk for open conversion. It seems that more conversions are performed in the early postoperative period, despite perceptions that conversion is a delayed phenomenon. In all instances, conversion is associated with significant morbidity and mortality and highlights the importance of appropriate patient selection at the time of index EVAR.

Contemporary management and outcomes of complex vascular surgical groin wound infections.

OBJECTIVE: Vascular surgical groin wound infection (VS-GWI) has multiple causes and frequently is manifested as a limb- or life-threatening problem, resulting in significant morbidity and mortality. For patients undergoing operative extirpation, in situ repair, extra-anatomic bypass, or ligation can be used; however, limited data exist describing comparative results of the different operative choices or conduit subtypes. Therefore, we sought to describe our experience with management of VS-GWI and to detail outcomes of the different strategies. METHODS: Patients (2003-2017) undergoing surgical treatment of VS-GWI (Szilagyi grade III) secondary to primary infectious arteritis or infected pseudoaneurysm after percutaneous intervention as well as previous prosthetic graft placement were reviewed. The primary end point was major adverse limb events (MALEs; major amputation, graft occlusion, or unplanned reintervention). Secondary end points included 30-day mortality, wound healing, amputation-free survival (AFS), and all-cause mortality. Cox proportional hazards modeling was used to determine relative risk of end points; Kaplan-Meier methodology was employed to estimate freedom from outcomes. RESULTS: There were 149 patients (age, 65 ± 11 years; body mass index, 27 ± 6 kg/m2; 70% male; 32% diabetes) identified, of whom 120 (81%) had unilateral and 29 (19%) had bilateral VS-GWI. Indications included infected prosthetic bypass (88% [n = 131]; infrainguinal, 107; suprainguinal, 24) and primary infectious femoral artery complications (12% [n = 18]). A majority underwent single-stage operations (87% [n = 129]). In situ reconstruction occurred in 87% (n = 129); 9% (n = 13) underwent ligation, and 6% (n = 7) received extra-anatomic revascularization. Autogenous conduit was used most commonly (68% [n = 101/149]; 88% single stage), of which 81% (n = 80) were femoral vein. The remaining patients received cadaveric (15% [n = 23]; 87% single stage) or prosthetic (8% [n=12]; 67% single stage) grafts. Adjunctive myocutaneous flap was used in 37% (n = 54). Length of stay was 19 ± 15 days and 30-day mortality was 7% (n = 10), with no difference between conduit repair types. All femoral wounds healed (mean follow-up, 17 ± 11 months); however, 33% (n = 49) underwent reoperation (unplanned graft reintervention, 33%; graft occlusion, 16%; wound débridement, 15%; major amputation, 11%). Reinfection occurred in 17% (n = 27), with no difference between groups. MALE rate was 22% (n = 33; most were arterial reinterventions, 19%), with no difference in single-stage vs multistage, in situ vs extra-anatomic, or autogenous vs nonautogenous conduit strategies Predictors of MALE included younger age (hazard ratio [HR], 1.6 per decade; 95% confidence interval [CI], 1.1-2.5; P = .02) and lower body mass index (<25 kg/m2; HR, 1.6 per BMI category; 95% CI, 1.1-2.5; P = .02). Overall, 1- and 3-year freedom from MALE, AFS, and survival were as follows: MALE, 74% ± 5% and 63% ± 6%; AFS, 68% ± 4% and 58% ± 5%; survival, 78% ± 3% and 70% ± 4%. Autogenous conduit use was associated with better survival (HR, 0.5; 95% CI, 0.3-0.8; 1-year: 83% ± 4% vs nonautogenous, 78% ± 4%; 3-year: 68% ± 8% vs 53% ± 9%; log-rank, P = .006). CONCLUSIONS: An individualized approach to operative strategy and conduit choice leads to comparable outcomes in this challenging group of patients. VS-GWI can be safely managed with in situ, autogenous reconstruction in a majority of patients with acceptable mortality, excellent wound healing rates, and improved overall survival. However, a significant proportion of patients experience reinfection and MALEs, the preponderance of which are arterial reintervention, mandating need for close follow-up and graft surveillance.

Risk score for nonhome discharge after lower extremity bypass.

OBJECTIVE: Patients undergoing lower extremity bypass (LEB) for peripheral artery disease require intensive health care resource utilization including rehabilitation and skilled nursing facilities. However, few studies have evaluated factors that lead to nonhome discharge (NHD) in this population of patients. This study sought to predict NHD by preoperative risk factors in patients undergoing LEB for peripheral artery disease using a novel risk score. METHODS: The Vascular Study Group of New England database was queried for elective LEB for peripheral artery disease including claudication and critical limb ischemia from 2003 to 2017. Patients were excluded if the procedure was not elective, if they were not admitted from home, if they were bedridden, or if they died during the index admission. Only preoperative factors were considered in the analysis. The primary end point was NHD including rehabilitation and skilled nursing facilities. Data were split two-thirds for model derivation and one-third for validation. In the derivation cohort, bivariate analysis assessed the association of preoperative factors with NHD. A parsimonious manual stepwise binary logistic regression for NHD aimed at maximizing the C statistic while maintaining model simplicity was performed. A risk score was developed using the ß coefficients and applied to the validation data set. The risk score performance was assessed using a C statistic and Hosmer-Lemeshow test for model fit. RESULTS: There were 10,145 cases included with an overall NHD rate of 26.4% (n = 2676). Mean age was 66 years (range, 41-90 years). NHD patients were older (72 years vs 64 years; P < .01) and more frequently male (57.2% vs 42.8%; P < .01) and nonwhite (16.1% vs 9.9%; P < .01); they more frequently had tissue loss (54.2% vs 23.0%; P < .01), anemia (16.0% vs 5.3%; P < .01), severe cardiac comorbidity (21.8% vs 10.5%; P < .01), and insulin-dependent diabetes (33.3% vs 18.2%; P < .01). On multivariable analysis, factors associated with NHD included age, sex, nonwhite race, tissue loss, cardiac comorbidity, partial ambulatory deficit, and insulin-dependent diabetes. The C statistic was 0.78 in the derivation group and 0.79 in the validation group, with Hosmer-Lemeshow P > .999. The risk score ranged from 0 to 18, with a mean score of 4 (standard deviation ±3.5). The risk score was divided into low risk (0-4 points; n = 5272 [52%]; NHD = 10.1%]), moderate risk (5-9 points; n = 3663 [36.7%]; NHD = 36.7%), and high risk (≥10 points; n = 1210 [11.9%]; NHD = 66.1%). CONCLUSIONS: This novel risk score was highly predictive for NHD after LEB for peripheral artery disease using only preoperative comorbidities. High-risk patients account for 12% of LEB but nearly a third of all patients requiring NHD. This risk score can be used preoperatively to determine high-risk patients for NHD, which may help improve preoperative counseling and hospital efficiency by allocating resources appropriately.

Vascular access for hemodialysis in the elderly.

OBJECTIVE: The objective of this study was to compare the outcomes of arteriovenous fistulas (AVFs) with arteriovenous grafts (AVGs) in a large population-based cohort of elderly patients in the United States. METHODS: A retrospective analysis was performed of all patients ≥75 years old in the prospectively maintained United States Renal Database System who had an AVF or AVG placed for hemodialysis (HD) access between January 2007 and December 2011. Outcomes were mortality, conduit patency, maturation, time to catheter-free dialysis, and infection. A χ2 test, Student t-test, Kaplan-Meier analysis, and multivariable Cox regression analysis were employed. RESULTS: Of the 124,421 patients studied, there were 19,173 (15%) AVF initiates, 4480 (4%) AVG initiates, 29,872 (24%) AVF converts, 10,712 (9%) AVG converts, and 59,824 (48%) patients who persisted on HD catheters. Compared with AVF initiates, relative mortality was significantly higher for AVG initiates (adjusted hazard ratio [aHR], 1.24; P < .001), AVF converts (aHR, 1.36; P < .001), AVG converts (aHR, 1.62; P < .001), and catheter-persistent patients (aHR, 2.23; P < .001). Primary patency (aHR, 1.21; P < .001) and primary assisted patency (aHR, 1.31; P < .001) were higher for AVF. Secondary patency was higher for AVGs within the first 4 months (aHR, 1.12; P < .001) but higher for AVFs beyond that time point (aHR, 1.25; P < .001). Maturation rate and median time to maturation were 80% vs 84% (P < .001) and 46 vs 26 days (P < .001) for AVF vs AVG. CONCLUSIONS: Pre-emptive AVF remains the best mode of HD in elderly patients who can tolerate surgery. Patients who cannot tolerate pre-emptive surgery or have to initiate HD on an urgent basis with a catheter should convert to AVF when it is feasible if life expectancy is >4 months. If life expectancy is <4 months, surgical risk and quality of life should be considered in making the decision to persistently dialyze through HD catheter or to convert to AVG.

Feasibility and Outcomes of Femoral Vein Harvest for Dialysis Access and Arterial Reconstruction.

BACKGROUND: We describe the feasibility and long-term outcomes of using femoral vein (FV) for arteriovenous fistula (AVF) and lower extremity bypass (LEB) creation. METHODS: All patients undergoing AVF or LEB using autogenous FV by a single surgeon (April 2006 to September 2013) were reviewed. Perioperative (30-d) complications and long-term outcomes are described. RESULTS: Forty-four patients underwent vascular reconstruction with FV (AVF = 27 and LEB = 17). Perioperative morbidity was 43.2%, including harvest site infection and or seroma in 15.9%. No patients suffered from compartment syndrome or venous thromboembolic event. At median follow-up of 50.0 mon, overall patency was 70.4% for AVF (primary = 37.0% and secondary = 70.3%) and 76.5% for LEB (primary = 70.6% and secondary = 76.5%). Long-term lower extremity swelling occurred in 18.2% of patients. CONCLUSIONS: Perioperative morbidity following FV harvest is high, but long-term patency rates are excellent. FV harvest is feasible and should be considered as a valid conduit in patients without useable great saphenous vein or other more commonly used sources of autogenous vein.

A Regional Experience with Carotid Endarterectomy in Patients with a History of Neck Radiation.

BACKGROUND: Historically, a history of neck radiation has been considered as an anatomic risk factor for poor outcomes after carotid endarterectomy (CEA). However, this is based on small and primarily single institution reports with few comparative series. This study uses a regional quality database to compare perioperative outcomes of CEA in patients with and without a history of neck radiation (RAD and NORAD, respectively). METHODS: The Vascular Study Group of New England database was queried for all CEA from 2003 to 2017. The RAD group included a history of neck radiation. Primary end points included perioperative stroke (30-day), myocardial infarction (MI) (in-hospital), death (30-day), a composite end point including major adverse events (MAEs: stroke, MI, and death), and long-term survival. RESULTS: Overall, 18,832 patients underwent CEA (18,551 NORAD, 281 RAD). Baseline demographics differed in the following: the RAD group more frequently had a history of contralateral carotid artery stenting (1.4% vs. 0.3%, P = 0.009), anatomic high risk features (12.8% vs. 1.3%, P < 0.001), and contralateral carotid occlusion (5.3% vs. 2.4%, P = 0.005). The NORAD cohort comprised mostly women (38.9% vs. 29.5%, P < 0.001), had American Society of Anesthesiologists class 4 or 5 (8.0% vs. 4.6%, P = 0.035), had higher body mass index (28.3 ± 5.6 vs. 27.1 ± 5.4, P < 0.001), on a beta blocker preoperatively (68.0% vs. 62.3%, P = 0.042), and had major cardiovascular comorbidities including coronary artery disease (29.6% vs. 22.1%, P = 0.006). There were no differences in the percent stenosis, proportion symptomatic (37.4% vs. 34.2%, P = 0.259), use of preoperative antiplatelet agents or statins. Electroencephalography monitoring was more frequently used in RAD (54.5% vs. 46.0%, P = 0.005). There was no difference in perioperative complications, including stroke (RAD 0.4% vs. NORAD 0.7%, P > 0.999), MI (0.4% vs. 0.9%, P = 0.736), death (0.7% vs. 0.6%, P = 0.683), MAE (2.1% vs. 2.2%, P > 0.999), or long-term survival (79.9% vs. 85.0%, P = 0.357). When only symptomatic or asymptomatic stenosis was considered, there remained no difference in primary end points. However, perioperative neurologic events (transient ischemic attack or stroke) was higher in symptomatic RAD versus symptomatic NORAD (6.7% vs. 2.6%, P = 0.020). CONCLUSIONS: This regional experience with CEA in RAD patients shows similar perioperative morbidity, mortality, and long-term survival when compared with CEA for standard surgical patients (NORAD). Symptomatic presentation was associated with higher perioperative neurologic events, but this was not reflected in stroke rates. RAD is not always a contraindication to CEA and select patients can expect outcomes comparable to standard surgical patients.

A novel, validated risk score to predict surgical site infection after pancreaticoduodenectomy.

BACKGROUND: Although pancreaticoduodenectomy (PD) outcomes have improved, complications including surgical site infection (SSI) remain common. We present a stratification tool to predict risk for SSI after PD. METHODS: Data was retrospectively reviewed on all patients undergoing PD at a tertiary hospital (9/2011-8/2014). Potential SSI risk factors identified by univariate analysis were incorporated into a multivariate logistic regression model. The resulting odds ratios were converted into a point system to create an SSI risk score with internal validation. RESULTS: Six hundred seventy nine patients underwent PD and were chronologically split into derivation (443 patients) and validation (236 patients) groups. There was no difference in demographics or perioperative outcomes between groups. Overall thirty-day SSI was observed in 17.2% (n = 117). Neoadjuvant chemotherapy and/or radiation, intraoperative red blood cell transfusion, operative time greater than 7 h, preoperative bile stent/drain, and vascular resection were associated with SSI in univariate analysis (all p < 0.05). On multivariate analysis, preoperative bile stent/drain and neoadjuvant chemotherapy were independent predictors of SSI, each assigned 1 point (both p < 0.001). Patients with 0, 1, and 2 points, respectively, had 0%, 32%, and 64% predicted risk of SSI (AUC = 0.73, R2 = 0.93). The model performed equivalently in the validation group (AUC = 0.77, R2 = 0.99). CONCLUSION: This novel, validated risk score accurately predicts SSI risk after pancreaticoduodenectomy. Identifying the highest risk patients can help target interventions to reduce SSI.

Performance of the Aorfix endograft in severely angulated proximal necks in the PYTHAGORAS United States clinical trial.

OBJECTIVE: This study compared the performance of the Aorfix endograft (Lombard Medical, Oxfordshire, United Kingdom) in standard (<60°), highly angled (60°-90°), and severely angled (>90°) aortic necks in the PYTHAGORAS study and evaluated changes in neck morphology over time. METHODS: PYTHAGORAS is a prospective nonrandomized clinical trial of the Aorfix endograft. We divided the endovascular aneurysm repair (EVAR) cohort into groups by standard, high, and severe neck angle. The primary control group was patients concurrently undergoing open repair. Mortality at 30 days, 1 year, and 2 years and 30-day freedom from Society for Vascular Surgery major adverse events for the EVAR groups was compared with the open control. Aneurysm sac change, type I and III endoleaks, graft migration, and the reintervention rate at 1 and 2 years was compared between the standard, highly, and severely angled populations. The relative risk of graft complications with a neck diameter increase >10% was also calculated. At predetermined anatomic points, the effect of oversizing on aortic diameter was evaluated by calculating oversize percentage ([1 - outer aortic diameter measured at a given time/stent graft diameter] × 100%) preoperatively and at 3 years. In addition, the average oversizing percentage at 30 days and annually at 1 to 5 years was compared with the preoperative oversizing percentage. Finally, complication rates with ≥30% vs <30% planned oversizing were compared. RESULTS: The adverse event rate was lower for every EVAR group than the open control. In addition, the mortality rates at 30 days, 1 year, and 2 years were similar between the standard-angle (1.5%, 3.0%, 4.5%), high-angle (0.9%, 7.3%, 13.8%), and severe-angle (4.8%, 9.5%, 14.3%) EVAR groups and the open control groups (1.3, 6.6%, 10.5%). At 1 and 2 years, there was no difference in graft complications among the EVAR groups. However, with neck dilatation of >10% at 5 mm above the proximal renal and 1 mm below the distal renal, there was an increased risk of graft migration (relative risk, 4.38 [P = .01] and 4.33 [P = .002], respectively). For all predetermined anatomic points, the oversizing percentage decreased over time. The rate of oversize percentage decrease was faster at more distal aortic locations, reaching <10% at 30 days 15 mm below the renal, at 2 years 7 mm below the renal, and at 5 years 1 mm below the renal (P < .001 for all). Half the oversize percentage achieved at the index procedure remained at 3 years (Pearson correlation coefficient = 0.5). However, there was no difference in complications between the ≥30% and <30% planned oversize groups. CONCLUSIONS: The Aorfix endograft has performed well in excluding aneurysms with standard and highly angled aortic neck anatomy.

Sex disparities in patients with acute aortic dissection: A scoping review.

Disparities in outcomes for patients with cardiovascular disease and those undergoing cardiac or vascular operations are well-established. These disparities often span several dimensions and persist despite advancements in medical and surgical care; sex is among the most pervasive. Specifically, females sex has been implicated as a predictor of poor outcomes in both patients with acute type A aortic dissections (ATAADs) and type B aortic dissections (TBADs). For instance, one study, using the International Registry of Acute Aortic Dissection database, found that females with acute aortic dissection-including ATAAD and TBAD that were either medically or surgically managed-had 40% higher odds of in-hospital mortality than men. Notably, both types of acute aortic dissections affect men more commonly than females and can be life-threatening without prompt, appropriate treatment. The underlying mechanisms for these disparities are unclear but are thought to be multifactorial. The association of sex with patterns of disease and outcomes in patients with ATAAD or TBAD remains unclear, with conflicting reports from different studies. Thus, we sought to review the literature regarding sex disparities in patients with ATAAD and TBAD.

National Treatment Patterns and Outcomes for Hospitalized Patients with Chronic Limb-Threatening Ischemia and End-Stage Kidney Disease.

BACKGROUND: Chronic limb-threatening ischemia (CLTI) can be associated with dismal outcomes but there are limited real-world data to further define the impact of end-stage kidney disease (ESKD) on outcomes nationally in this subset of patients. We sought to characterize national patterns of inpatient treatment of CLTI and compare outcomes in patients without ESKD. METHODS: The National Inpatient Sample was queried from 2015-2018 for all hospital admissions including treatment for CLTI. Mixed-effects linear and logistic regression models were used to estimate the effect of ESKD on outcomes and treatment choice. RESULTS: We identified 11 652 hospital admissions with CLTI alone and 2705 with CLTI + ESKD. Hospital admissions with CLTI + ESKD patients included patients who were younger (66 vs 69 years, P < .0001), less likely to be white (39% vs 63%, P < .0001), and more likely to reside in lower income large metropolitan areas. Admissions for CLTI + ESKD patients had a lower likelihood of open arterial reconstruction (OR .40, P < .0001) and a higher likelihood of endovascular revascularization or major limb amputation (OR 1.70, P < .0001). Admissions for CLTI + ESKD also had a 4.5- and 1.5-fold higher odds of in-hospital death and complications. These findings were associated with a longer LOS (P < .0001), increased probability of discharge to rehabilitation facility (50% vs 41%, P < .0001), and greater hospital charges (median, $107 K vs $85 K, P < .0001). CONCLUSIONS: Compared to hospital admissions for patients without ESKD, admissions for patients with CLTI + ESKD demonstrated distinctive demographic characteristics, a lower likelihood of open revascularization and a higher likelihood of endovascular revascularization and major limb amputation. Chronic limb-threatening ischemia + ESKD hospital admissions showed worse overall outcomes and greater resource utilization compared to CLTI admissions without ESKD.

Chronic mesenteric ischemia-induced intestinal dysbiosis resolved after revascularization.

Objective: Chronic mesenteric ischemia (CMI) is a debilitating condition arising from intestinal malperfusion from mesenteric artery stenosis or occlusion. Mesenteric revascularization has been the standard of care but can result in substantial morbidity and mortality. Most of the perioperative morbidity has been secondary to postoperative multiple organ dysfunction, potentially from ischemia-reperfusion injury. The intestinal microbiome is a dense community of microorganisms in the gastrointestinal tract that help regulate pathways ranging from nutritional metabolism to the immune response. We hypothesized that patients with CMI will have microbiome perturbations that contribute to this inflammatory response and could potentially normalize in the postoperative period. Methods: We performed a prospective study of patients with CMI who had undergone mesenteric bypass and/or stenting from 2019 to 2020. Stool samples were collected at three time points: preoperatively at the clinic, perioperatively within 14 days after surgery, and postoperatively at the clinic at >30 days after revascularization. Stool samples from healthy controls were used for comparison. The microbiome was measured using 16S rRNA sequencing on an Illumina-MiSeq sequence platform and analyzed using the QIIME2 (quantitative insights into microbial ecology 2)-DADA2 bioinformatics pipeline with the Silva database. Beta-diversity was analyzed using a principal coordinates analysis and permutational analysis of variance. Alpha-diversity (microbial richness and evenness) was compared using the nonparametric Mann-Whitney U test. Microbial taxa unique to CMI patients vs controls were identified using linear discriminatory analysis effect size analysis. P < .05 was considered statistically significant. Results: Eight patients with CMI had undergone mesenteric revascularization (25% men; average age, 71 years). Nine healthy controls were also analyzed (78% men; average age, 55 years). Bacterial alpha-diversity (number of operational taxonomic units) was dramatically reduced preoperatively compared with that of the controls (P = .03). However, revascularization partially restored the species richness and evenness in the perioperative and postoperative phases. Beta-diversity was only different between the perioperative and postoperative groups (P = .03). Further analyses revealed increased abundance of Bacteroidetes and Clostridia taxa preoperatively and perioperatively compared with the controls, which was reduced during the postoperative period. Conclusions: The results from the present study have shown that patients with CMI have intestinal dysbiosis that resolves after revascularization. The intestinal dysbiosis is characterized by the loss of alpha-diversity, which is restored perioperatively and maintained postoperatively. This microbiome restoration demonstrates the importance of intestinal perfusion to sustain gut homeostasis and suggests that microbiome modulation could be a possible intervention to ameliorate acute and subacute postoperative outcomes in these patients.