Impact of COVID-19 on patients undergoing scheduled procedures for chronic venous disease.

OBJECTIVE: The COVID-19 pandemic has drastically altered the medical landscape. Various strategies have been employed to preserve hospital beds, personal protective equipment, and other resources to accommodate the surges of COVID-19 positive patients, hospital overcapacities, and staffing shortages. This has had a dramatic effect on vascular surgical practice. The objective of this study is to analyze the impact of the COVID-19 pandemic on surgical delays and adverse outcomes for patients with chronic venous disease scheduled to undergo elective operations. METHODS: The Vascular Surgery COVID-19 Collaborative (VASCC) was founded in March 2020 to evaluate the outcomes of patients with vascular disease whose operations were delayed. Modules were developed by vascular surgeon working groups and tested before implementation. A data analysis of outcomes of patients with chronic venous disease whose surgeries were postponed during the COVID-19 pandemic from March 2020 through February 2021 was performed for this study. RESULTS: A total of 150 patients from 12 institutions in the United States were included in the study. Indications for venous intervention were: 85.3% varicose veins, 10.7% varicose veins with venous ulceration, and 4.0% lipodermatosclerosis. One hundred two surgeries had successfully been completed at the time of data entry. The average length of the delay was 91 days, with a median of 78 days. Delays for venous ulceration procedures ranged from 38 to 208 days. No patients required an emergent intervention due to their venous disease, and no patients experienced major adverse events following their delayed surgeries. CONCLUSIONS: Interventions may be safely delayed for patients with venous disease requiring elective surgical intervention during the COVID-19 pandemic. This finding supports the American College of Surgeons' recommendations for the management of elective vascular surgical procedures. Office-based labs may be safe locations for continued treatment when resources are limited. Although the interventions can be safely postponed, the negative impact on quality of life warrants further investigation.

Carotid Artery Operation Delay During the Covid-19 Pandemic: Results of a Multicenter International Study.

BACKGROUND: To measure the impact of the COVID-19 pandemic on the management of patients with carotid artery stenosis. METHODS: We prospectively collected data from 25 centers (19 centers in the United States and 6 centers internationally) on postponed carotid artery operations between March 2020 and January 2022. We describe the characteristics of these patients and their planned operations, along with outcomes including mortality and neurological deterioration during the period of operative delay due to the COVID-19 pandemic. RESULTS: A total of 1,220 vascular operations were postponed during the pandemic, of them 96 patients presented with significant carotid stenosis (median stenosis of 71%; interquartile range; 70-80) and 80% of them were planned for carotid endarterectomy. Most patients were asymptomatic (69%), and 31% of patients were symptomatic (16% of patients had a stroke, 15% of patients had a transient ischemic attack, and 1% of patients experienced amaurosis fugax). The median length of surgical delay was 71 days (interquartile range: 45.5, 115.5). At the data entry time, 62% of patients had their carotid operations postponed and successfully completed. Most postponements (72%) were due to institutional policies aimed at resource conservation. During the delay, no patient decompensated or required an urgent operation. A total of 5 patients (5%) with carotid stenosis died while awaiting operations due to COVID-19. CONCLUSIONS: Our study of a cohort of patients with carotid artery stenosis who underwent a median delay of 71 days during the COVID-19 pandemic showed a disparate operation delay between US regions and internationally, most postponements were due to hospital policy, and none of the patients deteriorated or required an emergency surgery during the delay.

The impact of the COVID-19 pandemic on vascular surgery practice in the United States.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has led to widespread postponement and cancelation of elective surgeries in the United States. We designed and administered a global survey to examine the impact of COVID-19 on vascular surgeons. We describe the impact of the pandemic on the practices of vascular surgeons in the United States. METHODS: The Pandemic Practice, Anxiety, Coping, and Support Survey for Vascular Surgeons is an anonymous cross-sectional survey sponsored by the Society for Vascular Surgery Wellness Task Force disseminated April 14 to 24, 2020. This analysis focuses on pattern changes in vascular surgery practices in the United States including the inpatient setting, ambulatory, and vascular laboratory setting. Specific questions regarding occupational exposure to COVID-19, adequacy of personal protective equipment, elective surgical practice, changes in call schedule, and redeployment to nonvascular surgery duties were also included in the survey. Regional variation was assessed. The survey data were collected using REDCap and analyzed using descriptive statistics. RESULTS: A total of 535 vascular surgeons responded to the survey from 45 states. Most of the respondents were male (73.1%), white (70.7%), practiced in urban settings (81.7%), and in teaching hospitals (66.8%). Almost one-half were in hospitals with more than 400 beds (46.4%). There was no regional variation in the presence of preoperative COVID-19 testing, COVID-19 OR protocols, adherence to national surgical standards, or the availability of personal protective equipment. The overwhelming majority of respondents (91.7%) noted elective surgery cancellation, with the Northeast and Southeast regions having the most case cancellations 94.2% and 95.8%, respectively. The Northeast region reported the highest percentage of operations or procedures on patients with COVID-19, which was either identified at the time of the surgery or later in the hospital course (82.7%). Ambulatory visits were performed via telehealth (81.3%), with 71.1% having restricted hours. More than one-half of office-based laboratories (OBLs) were closed, although there was regional variation with more than 80% in the Midwest being closed. Cases performed in OBLs focused on critical limb ischemia (42.9%) and dialysis access maintenance (39.9%). Call schedules modifications were common, although the number of call days remained the same (45.8%). CONCLUSIONS: Vascular surgeons in the United States report substantial impact on their practices during the COVID-19 pandemic, and regional variations are demonstrated, particularly in OBL use, intensive care bed availability, and COVID-19 exposure at work.

Global vascular surgeons' experience, stressors, and coping during the coronavirus disease 2019 pandemic.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has led to unprecedented challenges for health care systems globally. We designed and administered a global survey to examine the effects of COVID-19 on vascular surgeons and explore the COVID-19-related stressors faced, coping strategies used, and support structures available. METHODS: The Pandemic Practice, Anxiety, Coping, and Support Survey for Vascular Surgeons was an anonymous cross-sectional survey sponsored by the Society for Vascular Surgery Wellness Task Force. The survey analysis evaluated the effects of COVID-19-related stressors on vascular surgeons measured using the Generalized Anxiety Disorder 7-item scale. The 28-item Brief Coping Orientation to Problems Experienced inventory was used to assess the active and avoidant coping strategies. Survey data were collected using REDCap (Research Electronic Data Capture) from April 14, 2020 to April 24, 2020 inclusive. Additional qualitative data were collected using open-ended questions. Univariable and multivariable analyses of the factors associated with the anxiety levels and qualitative analysis were performed. RESULTS: A total of 1609 survey responses (70.5% male; 82.5% vascular surgeons in practice) from 58 countries (43.4% from United States; 43.4% from Brazil) were eligible for analysis. Some degree of anxiety was reported by 54.5% of the respondents, and 23.3% reported moderate or severe anxiety. Most respondents (∼60%) reported using active coping strategies and the avoidant coping strategy of "self-distraction," and 20% used other avoidant coping strategies. Multivariable analysis identified the following factors as significantly associated with increased self-reported anxiety levels: staying in a separate room at home or staying at the hospital or a hotel after work (odds ratio [OR], 1.39; 95% confidence interval [CI], 1.08-1.79), donning and doffing personal protective equipment (OR, 1.81; 95% CI, 1.41-2.33), worry about potential adverse patient outcomes due to care delay (OR, 1.47; 95% CI, 1.16-1.87), and financial concerns (OR, 1.90; 95% CI, 1.49-2.42). The factors significantly associated with decreased self-reported anxiety levels were hospital support (OR, 0.83; 95% CI, 0.76-0.91) and the use of positive reframing as an active coping strategy (OR, 0.88; 95% CI, 0.81-0.95). CONCLUSIONS: Vascular surgeons globally have been experiencing multiple COVID-19-related stressors during this devastating crisis. These findings have highlighted the continued need for hospital systems to support their vascular surgeons and the importance of national societies to continue to invest in peer-support programs as paramount to promoting the well-being of vascular surgeons during and after the COVID-19 pandemic.

Open Endoaneurysmorrhaphy of 9-cm Ruptured Popliteal Aneurysm 7 Years after Initial Repair.

BACKGROUND: A previously repaired right popliteal artery aneurysm via a medial approach with proximal and distal ligation and interval bypass re-presented 7 years after the initial repair with a ruptured 9 × 25.5 cm right popliteal aneurysm. METHODS: Surgical repair was complex due to the large size of the aneurysm. Technique and management of popliteal aneurysm repair are discussed, along with a review of the current literature. RESULTS: A 58-year-old male with a 3.5 cm popliteal artery aneurysm was initially treated with end-to-end prosthetic bypass and proximal/distal aneurysm ligation from a medial-approach without complication. Seven years later, he presented with a 9-cm popliteal aneurysm rupture. Posterior approach endoaneurysmorrhaphy repair was far more complicated than expected with massive blood loss. Despite this, he was discharged without complication POD #5, but on POD #19 presented with cellulitis and underwent incision and drainage of retained hematoma with cultures positive for Strep dysgalactiae. With appropriate treatment, he was healed in 3 months. CONCLUSIONS: Surgical repair of large popliteal aneurysms can be challenging, but continued aneurysmal degeneration is a potential consequence if the sac continues to be pressurized from patent geniculate arteries. Surgical repair of large popliteal artery aneurysms is complex and requires adjunctive techniques to maximize success. A posterior approach is described and the literature reviewed to support recommendations for primary popliteal artery aneurysm repair and repair of large degenerated popliteal artery aneurysms. We recommend primary popliteal artery aneurysm repair from a posterior approach with endoaneurysmorrhaphy and an interposition bypass. For ruptured large popliteal artery aneurysms, there is a high risk of hemorrhage and wound complications. Therefore, we recommend the use of a tourniquet, surgical drain and to consider the collection of intraoperative cultures to guide potential antibiotic management.

The Impact of the COVID-19 Pandemic on Vascular Surgery Trainees in the United States.

BACKGROUND: The impact of the coronavirus disease 19 (COVID-19) pandemic on health care workers has been substantial. However, the impact on vascular surgery (VS) trainees has not yet been determined. The goals of our study were to gauge the impact of COVID-19 on VS trainees' personal and professional life and to assess stressors, coping, and support structures involved in these trainees' response to the COVID-19 pandemic. METHODS: This was an anonymous online survey administered in April 12-24, 2020 during the surge phase of the global COVID-19 pandemic. It is a subset analysis of the cross-sectional Society for Vascular Surgery Wellness Committee Pandemic Practice, Anxiety, Coping, and Support Survey. The cohort surveyed was VS trainees, integrated residents and fellows, in the United States of America. Assessment of the personal impact of the pandemic on VS trainees and the coping strategies used by them was based on the validated Generalized Anxiety Disorder 7-item (GAD-7) scale and the validated 28-time Brief Coping Orientation to Problems Experienced inventory. RESULTS: A total of 145 VS trainees responded to the survey, with a 23% response rate (145/638). Significant changes were made to the clinical responsibilities of VS trainees, with 111 (91%) reporting cancellation of elective procedures, 101 (82%) with call schedule changes, 34 (24%) with duties other than related to VS, and 29 (24%) participation in outpatient care delivery. Over one-third (52/144) reported they had performed a procedure on a patient with confirmed COVID-19; 37 (25.7%) reported they were unaware of the COVID-19 status at the time. The majority continued to work after exposure (29/34, 78%). Major stressors included concerns about professional development, infection risk to family/friends, and impact of care delay on patients. The median score for GAD-7 was 4 (interquartile range 1-8), which corresponds to no or low self-reported anxiety levels. VS trainees employed mostly active coping and rarely avoidant coping mechanisms, and the majority were aware and used social media and online support systems. No significant difference was observed between integrated residents and fellows, or by gender. CONCLUSIONS: The pandemic has had significant impact on VS trainees. Trainees reported significant changes to clinical responsibilities, exposure to COVID-19, and pandemic-related stressors but demonstrated healthy coping mechanisms with low self-reported anxiety levels. The VS community should maintain awareness of the impact of the pandemic on the professional and personal development of surgeons in training. We recommend adaptive evolution in training to accommodate the changing learning environment for trainees.

The initial experience and response of vascular surgeons in Michigan during the COVID-19 pandemic.

BACKGROUND/OBJECTIVE: The unprecedented pandemic spread of the novel coronavirus has severely impacted the delivery of healthcare services in the United States and around the world, and has exposed a variety of inefficiencies in healthcare infrastructure. Some states have been disproportionately affected such as New York and Michigan. In fact, Detroit and its surrounding areas have been named as the initial Midwest epicenter where over 106,000 cases have been confirmed in April 2020. METHOD, RESULTS AND CONCLUSIONS: Facilities in Southeast Michigan have served as the frontline of the pandemic in the Midwest and in order to cope with the surge, rapid, and in some cases, complete restructuring of care was mandatory to effect change and attempt to deal with the emerging crisis. We describe the initial experience and response of 4 large vascular surgery health systems in Michigan to COVID-19.

Brazilian vascular surgeons experience during the coronavirus (COVID-19) pandemic.

BACKGROUND: The COVID-19 pandemic has made a significant impact on all spheres of society. The objective of this study was to examine the impact of COVID-19 on the practices, finances, and social aspects of Brazilian vascular surgeons' lives. METHODS: This is a descriptive analysis of the responses from Brazilian vascular surgeons to the cross-sectional anonymous Society for Vascular Surgery Wellness Task Force Pandemic Practice, Anxiety, Coping, and Support Survey for Vascular Surgeons disseminated 14-24 April 2020. Survey dissemination in Brazil occurred mainly via the Brazilian Society of Angiology and Vascular Surgery (SBACV) and social media. The survey evaluated the impact of the COVID-19 pandemic on vascular surgeons' lives by assessing COVID-19-related stressors, anxiety using theGeneral Anxiety Disorder (GAD)-7 scale, and coping strategies using the Brief Coping Orientation to Problems Experienced (Brief-COPE) inventory. RESULTS: A total of 452 responses were recorded from Brazil, with 335 (74%) respondents completing the entire survey. The majority of respondents were males (N = 301, 67%) and practiced in an urban hospitals. The majority of respondents considered themselves at high risk to be infected with COVID-19 (N = 251, 55.8%), and just over half the respondents noted that they had adequate PPE at their primary hospital (N = 171, 54%). One hundred and nine (35%) surgeons confirmed that their hospitals followed professional surgical society guidelines for prioritizing surgeries during the pandemic. At the time of the survey, only 33 (10%) surgeons stated they have pre-operative testing of patients for COVID-19 available at their hospital. Academic vascular surgeons reported being redeployed more often to help with other non-vascular duties compared to community-based or solo practitioners (43% vs. 30% vs. 21% respectively, P = .01). Severe anxiety due to pandemic-related financial concerns was similar in those surgeons practicing solo compared to those in community- or academic-based/group practice (46% vs. 38% vs. 22%; P = .54). The respondents reported their anxiety levels as mild based on the stressors investigated instead of moderate-severe (54% vs. 46%; P = .04). Social media was utilized heavily during the pandemic, with video gatherings being the most commonly used tool (76%). Self-distraction (60%) and situational acceptance (81%) were the most frequently reported coping mechanisms used among Brazilian vascular surgeons. CONCLUSION: The COVID pandemic has greatly affected healthcare providers around the world. At the time of this survey, Brazilian vascular surgeons are reporting low anxiety levels during this time and are using mostly active coping mechanisms.

Proper technical procedures improved outcomes in a retrospective analysis of EVAS FORWARD IDE trial 3-year results.

OBJECTIVE: Adverse outcomes observed late in the Nellix EndoVascular Aneurysm Sealing (EVAS) System (Endologix, Inc, Irvine, Calif) investigational device exemption trial prompted refinement of the anatomic instructions for use (IFU). This study aimed to investigate the association of procedural factors during Nellix endograft deployment and patient outcomes. METHODS: We retrospectively reviewed 1-month imaging of 333 patients enrolled in the prospective, multicenter EVAS investigational device exemption trial between January 2014 and September 2016. Initial observations of those patients who met revised anatomic IFU yet still experienced late adverse events suggested that inadequate seal and low graft placement were common among these patients. Key procedural variables identified from a univariate analysis were applied to construct four cohorts stratified by procedural technical performance (technically adequate [P+] or technically inadequate [P-]) and the revised anatomic indications for use (anatomically within IFU [A+] or anatomically outside of IFU [A-]) and to compare them for aneurysm-related outcomes. A logistic regression analysis was performed to identify significant predictors of sac expansion or migration. RESULTS: Proximal and distal seal zones and low graft placement were identified by logistic regression analysis as significant predictors of sac expansion or migration. Accordingly, acquisition of ≥10-mm proximal and distal seal zones and the position of the lowest stent within 10 mm of the lowest renal artery were clinically justified as thresholds for a technically adequate procedure. Patients who did not achieve these parameters were deemed to have a technically inadequate procedure. By use of the proposed procedural adequacy criteria and established anatomic criteria, patients were stratified into four cohorts: A+/P+ (n = 77), A+/P- (n = 54), A-/P+ (n = 71), and A-/P- (n = 131). Three-year estimates of freedom from migration of 10 mm were 98.6% in A+/P+, 95.9% in A+/P-, 85.8% in A-/P+, and 80.1% in A-/P-; freedom from type IA endoleak estimates were 98.6% in A+/P+, 100% in A+/P-, 96.4% in A-/ P+, and 90.3% in A-/P- cohorts. Freedom from sac expansion and secondary intervention were 96.9% and 90.6% in A+/P+, 86.0% and 93.6% in A+/P-, 87.1% and 83.1% in A-/P+, and 80.5% and 79.8% in A-/P- groups, respectively. Two early deaths (aneurysm-related mortality) on days 4 and 12 postoperatively were reported within the A+/P- group. Kaplan-Meier estimates of freedom from all-cause mortality and aneurysm-related mortality at 3 years were similar between cohorts. CONCLUSIONS: This post hoc analysis suggests that achieving a 10-mm proximal and distal seal with adequate positioning of the endograft with respect to the renal arteries is associated with improved patient outcomes.

Managing central venous access during a health care crisis.

OBJECTIVE: During the COVID-19 pandemic, central venous access line teams were implemented at many hospitals throughout the world to provide access for critically ill patients. The objective of this study was to describe the structure, practice patterns, and outcomes of these vascular access teams during the COVID-19 pandemic. METHODS: We conducted a cross-sectional, self-reported study of central venous access line teams in hospitals afflicted with the COVID-19 pandemic. To participate in the study, hospitals were required to meet one of the following criteria: development of a formal plan for a central venous access line team during the pandemic; implementation of a central venous access line team during the pandemic; placement of central venous access by a designated practice group during the pandemic as part of routine clinical practice; or management of an iatrogenic complication related to central venous access in a patient with COVID-19. RESULTS: Participants from 60 hospitals in 13 countries contributed data to the study. Central venous line teams were most commonly composed of vascular surgery and general surgery attending physicians and trainees. Twenty sites had 2657 lines placed by their central venous access line team or designated practice group. During that time, there were 11 (0.4%) iatrogenic complications associated with central venous access procedures performed by the line team or group at those 20 sites. Triple lumen catheters, Cordis (Santa Clara, Calif) catheters, and nontunneled hemodialysis catheters were the most common types of central venous lines placed by the teams. Eight (14%) sites reported experience in placing central venous lines in prone, ventilated patients with COVID-19. A dedicated line cart was used by 35 (59%) of the hospitals. Less than 50% (24 [41%]) of the participating sites reported managing thrombosed central lines in COVID-19 patients. Twenty-three of the sites managed 48 iatrogenic complications in patients with COVID-19 (including complications caused by providers outside of the line team or designated practice group). CONCLUSIONS: Implementation of a dedicated central venous access line team during a pandemic or other health care crisis is a way by which physicians trained in central venous access can contribute their expertise to a stressed health care system. A line team composed of physicians with vascular skill sets provides relief to resource-constrained intensive care unit, ward, and emergency medicine teams with a low rate of iatrogenic complications relative to historical reports. We recommend that a plan for central venous access line team implementation be in place for future health care crises.

Explanting the Nellix Endovascular Aortic Sealing Endoprosthesis for Proximal Aortic Neck Failure.

Open conversion after endovascular aortic repair has inherent challenges particular to the device being explanted. The Nellix endograft is unlike any other device as it uses polymer filling of endobags within the aorto-iliac lumen to seal the abdominal aortic aneurysm (AAA) sac, a developing concept known as endovascular aneurysm sealing. Conversion to open repair of AAA treated with the Nellix endograft has rarely been discussed. Explants that have been previously reported were for graft infection. We present 2 Nellix graft explants that were required for device migration and subsequent development of a type IA endoleak. The technique and nuances observed during open conversion of this novel endograft for proximal aortic neck failure is described in this report.

Pilot study to assess the use of a fluorescence imaging system for assessment of amputation healing.

OBJECTIVE:: The purpose of this study was to use a fluorescence imaging system (FIS) (SPYElite, NOVADAQ, US) during lower extremity amputations and develop parameters to predict amputation healing, for which there are no proven, objective tests. We hypothesised that the FIS may identify areas of poor perfusion at the time of amputation and predict potential healing complications. There are no studies involving the FIS used in this study in lower extremity amputation. METHOD:: This prospective cohort study involved patients requiring either below- or above-knee-amputation at one, mid-western medical centre. The FIS was used as per manufacturer's instructions after wound closure and before dressing. Procedure and operative management was unchanged. Through the FIS, perfusion values were plotted along the amputation site to visualise and quantify intraoperative perfusion and to compare with 30-day postoperative amputation healing. RESULTS:: Surgeons determined that all of the 18 participants had adequate perfusion at surgical wound closure. At 30 days, two subjects had wound dehiscence or infection; these correlated with low perfusion values on the FIS imaging. A further six subjects had marginal or low perfusion values, but did not develop wound failure. CONCLUSION:: It is feasible to use the FIS during amputation, however it did not perfectly predict healing course based on vascular perfusion. There were interesting patterns of poor perfusion that correlated with areas of dehiscence or infection but other patients had reduced perfusion that healed well. Due to the small sample size, no discernible perfusion value differences existed between patients who healed and patients with healing complications. A future, larger study may show that the FIS can be predictive of patient healing and aid decisions for intraoperative revision.

Refinement of anatomic indications for the Nellix System for endovascular aneurysm sealing based on 2-year outcomes from the EVAS FORWARD IDE trial.

BACKGROUND: The Nellix System (Endologix, Inc, Irvine, Calif) for endovascular aneurysm sealing (EVAS) is a novel approach to abdominal aortic aneurysm treatment and conceptually different from endovascular aneurysm repair, whereby polymer is employed to fill and actively manage the abdominal aortic aneurysm sac. One-year safety and effectiveness results of the Nellix pivotal trial demonstrated encouraging outcomes with very low morbidity and mortality and high procedural and treatment success. Two-year imaging revealed a signal of migration, leading to a field safety notification issued by the manufacturer on October 21, 2016, and a dedicated root cause analysis, resulting in refinements to the instructions for use (IFU). We report the 2-year results of the investigational device exemption pivotal trial stratified according to the new and original criteria for selection of patients. METHODS: Comprehensive engineering evaluations, statistical analyses, and clinical assessments were conducted looking at patients enrolled in the pivotal trial (N = 150), roll-in cohort (N = 29), and continued access program (N = 154). All patients in all cohorts were treated on-IFU at the time of enrollment. Logistic regression models supported the mechanism that migration with Nellix is associated with a small aortic flow lumen relative to a large aneurysm thrombus burden and large aortic neck diameters. Based on these findings, refinements to the IFU criteria were applied, excluding patients with a thrombus index (maximum aneurysm sac/maximum flow lumen diameter) >1.4, aortic neck diameter >28 mm, and aortic neck conicity (>10% diameter change along the infrarenal neck) and requiring a 10-mm distal seal zone in the iliac artery. RESULTS: Freedom from all-cause mortality at 2 years was 94%. Patient outcomes were then stratified on the refined morphologic criteria and analyzed retrospectively. Two-year freedom from composite endoleak was high among both cohorts (95% on-IFU vs 92% off-IFU). Freedom from migration was 97.7% on-IFU vs 93.2% off-IFU (P = .0125). Freedom from aneurysm enlargement was 98.1% on-IFU vs 93.5% off-IFU (P value is not available because of failure of log-rank test assumptions). Composite freedom from migration, type IA endoleak, or aneurysm expansion was 95.9% among the on-IFU cohort vs 85.1% in the off-IFU cohort (P = .0017). CONCLUSIONS: Consistent with the introduction of a novel therapy, the presentation of failure modes of EVAS over time was inevitable. Using detailed imaging as well as engineering and statistical analysis, we were able to understand risk factors for adverse events specific to EVAS and defined those patients best suited for Nellix. With this EVAS-specific approach to defining IFU, on-IFU patients were identified as those with large aneurysms with little thrombus that would be prone to type II endoleaks and sac expansion with traditional devices. When treated with Nellix, these patients were predicted to experience exceptional results, especially with regard to a low composite endoleak rate and low all-cause mortality.

One-year pivotal trial outcomes of the Nellix system for endovascular aneurysm sealing.

OBJECTIVE: The Nellix EndoVascular Aneurysm Sealing (EVAS) System (Endologix, Inc, Irvine, Calif) is a novel approach to abdominal aortic aneurysm (AAA) treatment whereby polymer is used to fill the AAA sac. We report 1-year results of the investigational device exemption pivotal trial. METHODS: Eligible patients were treated at 30 sites in the United States and Europe. Inclusion criteria required an asymptomatic infrarenal AAA, with a neck length ≥10 mm and ≤60° angle, iliac artery blood lumen diameter 9 to 35 mm, access artery diameter ≥6 mm, and serum creatinine ≤2 mg/dL. Follow-up included computed tomography angiography scans at 30 days, 6 months, and 1 year that were evaluated by a core laboratory. The primary safety end point was 30-day major adverse events (MAEs), which were compared with a performance goal of <56% (the Society for Vascular Surgery open repair control group rate). The primary effectiveness end point was treatment success at 1 year, which was compared with a performance goal of >80%. Treatment success required procedural technical success and absence of AAA rupture during follow-up, conversion to open surgical repair, endoleak (type I or III) at 1 year, migration >10 mm causing complications or requiring secondary intervention, aneurysm enlargement, or secondary procedures through 1 year for resolution of endoleak, device obstruction or occlusion, or device defect. RESULTS: Of 150 treated patients, 149 (99.3%) completed 1-year follow-up. The MAEs rate at 30 days was 2.7% (95% confidence interval, 0.7%-6.7%), satisfying the primary safety end point (<56%). The 1-year treatment success was 94% (95% confidence interval, 88.6%-97.4%), achieving the primary effectiveness end point (>80%). At 1 year, key secondary outcomes included 6.7% MAEs, 4.7% serious device-related events, 1.3% AAA-related mortality, 3.7% secondary interventions, and 0.7% surgical conversions. MAEs through 1 year included death (n = 6), stroke (n = 3), bowel ischemia (n = 2), renal failure (n = 2), respiratory failure (n = 2), and myocardial infarction (n =1). One iatrogenic AAA rupture occurred and one AAA rupture was reported during follow-up. AAA sac enlargement (>5 mm) was 1.5% at 1 year. Endoleaks were present in four patients (3.1%) at 1 year (1 type Ib and 3 type II). Migration >10 mm occurred in three patients (2.3%), but none required secondary intervention. CONCLUSIONS: Outcomes with this novel endovascular therapy for AAA, the Nellix EVAS System, are encouraging. The primary safety and effectiveness end points have been met. Low morbidity, low mortality, and high procedural and treatment success were achieved despite the inevitability of a learning curve and unique risks associated with a new device and technique. Long-term follow-up is in progress.

Outcomes for forearm and upper arm arteriovenous fistula creation with the transposition technique.

OBJECTIVE: To study the outcomes of three different types of arteriovenous fistula (AVF) transpositions (forearm cephalic vein transposition [FACVT], upper arm cephalic vein transposition [UACVT], and upper arm basilic vein transposition [UABVT]) for dialysis patients in a single center. METHODS: A 6-year retrospective review, from 2006 to 2012, was conducted at a single institution in which the surgical outcomes for three different types of AVF transposition were reviewed. Preoperative duplex vein mapping was obtained in all patients to choose the best vein for access. RESULTS: There were 165 patients identified with 77 FACVTs, 52 UACVTs, and 36 UABVTs. Primary access maturation rates for the FACVT, UACVT, and UABVT groups were 86%, 90%, and 97%, respectively (P = .19). All transposed, matured primary AVFs were used after a mean of 9.9 weeks, without additional intervention. Primary 1-year patency for the FACVT, UACVT, and UABVT groups were 63%, 61%, and 70%, respectively (P = .71). Primary assisted 1-year patency for the FACVT, UACVT, and UABVT groups were 93%, 93%, and 100%, respectively (P > .999). Mean operating room times and time to intervention were not significantly different between the groups. The postoperative hematoma rate was 2% and wound infection rate was 2%. Multivariate analysis indicated no significant predictors of time to failure (P > .05). CONCLUSIONS: With low primary failure rates, reduced need for secondary interventions before maturation, and 1-year primary assisted patency rates in excess of 93%, our study showed that the transposition technique, in our experience, is superior to previously published literature in hemodialysis access creation.

Results of the Nellix system investigational device exemption pivotal trial for endovascular aneurysm sealing.

OBJECTIVE: The Nellix EndoVascular Aneurysm Sealing system (Endologix, Inc, Irvine, Calif) is a novel approach to abdominal aortic aneurysm (AAA) endovascular repair whereby biocompatible polymer is employed to exclude and to seal the AAA sac. We report 30-day results of the U.S. pivotal trial. METHODS: Consecutive, eligible, consenting patients were enrolled at 29 sites in the United States and Europe. Inclusion criteria required an asymptomatic infrarenal AAA, with aortic neck length ≥10 mm and angle to the sac ≤60 degrees, aortic neck diameter of 18 to 32 mm, aneurysm blood lumen diameter ≤6 cm, common iliac artery lumen diameter of 9 to 35 mm, access artery diameter ≥6 mm, and serum creatinine level ≤2 mg/dL. Follow-up at 30 days included clinical assessment and computed tomography angiography evaluation of endoleaks and device integrity as assessed by a core laboratory. The primary safety end point is the incidence of independently adjudicated 30-day major adverse events (MAEs), with success defined as superiority with reference to the Society for Vascular Surgery open repair control group (56%). RESULTS: Between January and November 2014, 150 trial patients having a mean AAA diameter of 5.8 cm were enrolled and treated with the Nellix system with 100% procedural success. One early death (0.7%) occurred secondary to multisystem organ failure. All 149 surviving patients completed 30-day follow-up. There were no aneurysm ruptures, conversions, limb thromboses, stent fractures, or stent kinking. Five early MAEs occurred in four patients (2.7%) and included one death, bowel ischemia (1), renal failure (2), and respiratory failure (1). One (0.7%) secondary intervention to treat inadvertent coverage of a renal artery was performed. The core laboratory identified nine (6%) endoleaks (one type I, eight type II) on 30-day computed tomography angiography. Freedom from MAE was 97.3% (95% confidence interval, 93.3%-99.0%). CONCLUSIONS: In selected patients, perioperative outcomes with the Nellix system for endovascular aneurysm sealing are encouraging, with very low 30-day morbidity and mortality and high procedural success. The primary safety end point has been achieved. Longer term follow-up is in progress.

The association of perioperative transfusion with 30-day morbidity and mortality in patients undergoing major vascular surgery.

OBJECTIVE: Blood transfusions are common among patients undergoing major vascular surgery. Prior studies suggest an association between blood transfusion and increased morbidity and mortality among patients undergoing cardiac surgery. The predictors of perioperative transfusion and its impact on patients undergoing vascular surgery have been poorly defined. METHODS: We examined data from a large multicenter quality improvement vascular surgical registry of all patients undergoing elective or urgent open peripheral arterial disease procedures, endovascular aneurysm repair, or open abdominal aortic aneurysm (AAA) repair between January 2012 and December 2013. Emergency cases, carotid endarterectomy, and carotid artery stenting were excluded. Univariate and multivariate logistic regression modeling was used to identify predictors of transfusion and association of transfusion with outcomes. All regression models had Hosmer-Lemeshow P > .05 and area under the receiver operating characteristic curve of >0.8, confirming excellent goodness of fit and discrimination. RESULTS: Our study population comprised 2946 patients who underwent open peripheral arterial disease procedures (n = 1744), open AAA repair (n = 175), or endovascular aneurysm repair (n = 1027) at 22 hospitals. The overall transfusion rate was 25%, at a median nadir hemoglobin level of 7.7 g/dL. Independent factors predicting transfusion included female gender (odds ratio [OR], 2.6; 95% confidence interval [CI], 2.1-3.2), nonwhite race (OR, 2.7; 95% CI, 1.4-5.2), preoperative admission status (ie, acute care hospital) (OR, 2.6; 95% CI, 1.3-5.3), preoperative anemia (OR, 4.2; 95% CI, 3.3-5.1), congestive heart failure (OR, 1.4; 95% CI, 1.1-1.9), prior myocardial infarction (OR, 1.3; 95% CI, 1.01-1.6), clopidogrel (OR, 1.4; 95% CI, 1.2-1.8), open AAA repair (OR, 25; 95% CI, 17-39), open bypass (OR, 3.5; 95% CI, 2.7-4.6), and urgent procedures (OR, 1.4; 95% CI, 1.1-1.8). With adjustment for major covariates, perioperative transfusion was independently associated with death (OR, 6.9; 95% CI, 3.2-15), myocardial infarction (OR, 8; 95% CI, 3.7-17), and pneumonia (OR, 7.4; 95% CI, 3.3-17). CONCLUSIONS: Perioperative transfusion in vascular surgical patients is independently associated with increased 30-day morbidity and mortality. Given indeterminate causation, these data suggest the need for a prospective transfusion threshold study in vascular surgical patients.

Endovascular repair of bilateral common iliac artery aneurysms following open abdominal aortic aneurysm repair with preservation of both hypogastric arteries using commercially available stent grafts.

Endovascular treatment of aneurysmal disease has become the predominant form of repair for all aneurysms. Some areas continue to pose specific challenges to stay within the general tenets of successful repair, mainly achieving adequate seal without sacrificing other arterial pathways. Following aortic aneurysm repair, the common iliac arteries can continue to have aneurysmal degeneration. We present a case of bilateral common iliac artery aneurysms that presented 9 years after open repair of an infrarenal abdominal aortic aneurysm in conjunction with an extensive aortic dissection. These were repaired using endovascular techniques with preservation of both hypogastric arteries.

A primer on cohort studies in vascular surgery research.

Vascular research questions can be answered using various study designs. Observational studies are used frequently to address a wide range of clinical questions when randomized clinical trials are not feasible or practical. One of the powerful vascular research tools is the cohort study. The cohort study is a reliable observational study design in which individuals who share a common characteristic (a cohort) are followed over time and their outcomes are assessed at various intervals. This review focuses on the essential characteristics, design, implementation, bias, validity, and clinical significance of cohort studies and provides illustrative examples. A cohort study can be either a prospective or a retrospective study, depending on whether the outcome occurred before or after the enrollment of the cohort. Each type has its advantages and disadvantages. Confounding, selection, and information biases can all occur in cohort studies. Applications of the cohort study design include studying the natural history of a disease, describing a condition's frequency, and investigating multiple outcomes simultaneously.