How multidisciplinary clinics may mitigate socioeconomic barriers to care for chronic limb-threatening ischemia.

OBJECTIVE: Although multidisciplinary clinics improve outcomes in chronic limb-threatening ischemia (CLTI), their role in addressing socioeconomic disparities is unknown. Our institution treats patients with CLTI at both traditional general vascular clinics and a multidisciplinary Limb Preservation Program (LPP). The LPP is in a minority community, providing expedited care at a single facility by a consistent team. We compared outcomes within the LPP with our institution's traditional clinics and explored patients' perspectives on barriers to care to evaluate if the LPP might address them. METHODS: All patients undergoing index revascularization for CLTI from 2014 to 2023 at our institution were stratified by clinic type (LPP or traditional). We collected clinical and socioeconomic variables, including Area Deprivation Index (ADI). Patient characteristics were compared using χ2, Student t, or Mood median tests. Outcomes were compared using log-rank and multivariable Cox analysis. We also conducted semi-structured interviews to understand patient-perceived barriers. RESULTS: From 2014 to 2023, 983 limbs from 871 patients were revascularized; 19.5% of limbs were treated within the LPP. Compared with traditional clinic patients, more LPP patients were non-White (43.75% vs 27.43%; P < .0001), diabetic (82.29% vs 61.19%; P < .0001), dialysis-dependent (29.17% vs 13.40%; P < .0001), had ADI in the most deprived decile (29.38% vs 19.54%; P = .0061), resided closer to clinic (median 6.73 vs 28.84 miles; P = .0120), and had worse Wound, Ischemia, and foot Infection (WIfI) stage (P < .001). There were no differences in freedom from death, major adverse limb event (MALE), or patency loss. Within the most deprived subgroup (ADI >90), traditional clinic patients had earlier patency loss (P = .0108) compared with LPP patients. Multivariable analysis of the entire cohort demonstrated that increasing age, heart failure, dialysis, chronic obstructive pulmonary disease, and increasing WIfI stage were independently associated with earlier death, and male sex was associated with earlier MALE. Ten traditional clinic patients were interviewed via convenience sampling. Emerging themes included difficulty understanding their disease, high visit frequency, transportation barriers, distrust of the health care system, and patient-physician racial discordance. CONCLUSIONS: LPP patients had worse comorbidities and socioeconomic deprivation yet had similar outcomes to healthier, less deprived non-LPP patients. The multidisciplinary clinic's structure addresses several patient-perceived barriers. Its proximity to disadvantaged patients and ability to conduct multiple appointments at a single visit may address transportation and visit frequency barriers, and the consistent team may facilitate patient education and improve trust. Including these elements in a multidisciplinary clinic and locating it in an area of need may mitigate some negative impacts of socioeconomic deprivation on CLTI outcomes.

Revascularization Outcomes Stratified by Glycemic Control in Patients with Diabetes Mellitus and Chronic Limb-Threatening Ischemia.

BACKGROUND: The prevalence of chronic limb-threatening ischemia (CLTI) has increased alongside rising rates of diabetes mellitus (DM). While diabetic patients with CLTI have worse outcomes compared to patients without diabetes, conflicting data exist on the relationship between the severity of DM and CLTI outcomes. Close inspection of the relationship between DM severity and outcomes in CLTI may benefit surgical decision-making and patient education. METHODS: We retrospectively reviewed patients who received endovascular intervention or surgical bypass for CLTI at our multidisciplinary Limb Preservation Program from 2013 to 2019 to collect patient characteristics using Society for Vascular Surgery (SVS) reporting standards, arterial lesion characteristics from recorded angiograms, and outcomes, including survival, amputation, wound healing, and revascularization patency. Controlled DM was defined as SVS Grade 1 (controlled, not requiring insulin) and Grade 2 (controlled, requiring insulin), while uncontrolled DM was defined as SVS Grade 3 (uncontrolled), and DM severity was assessed using preoperative hemoglobin A1c (HgbA1c) values. Product-limit Kaplan-Meier was used to estimate survival functions. Univariable Cox proportional hazards analyses guided variable selection for multivariable analyses. RESULTS: Our Limb Preservation Program treated 177 limbs from 141 patients with DM. Patients with uncontrolled DM were younger (60.44 ± 10.67 vs. 65.93 ± 10.89 years old, P = 0.0009) and had higher HgbA1c values (8.97 ± 1.85% vs. 6.79 ± 1.10%, P < 0.0001). Fewer patients with uncontrolled DM were on dialysis compared to patients with controlled DM (15.6% vs. 30.9%, P = 0.0278). By Kaplan-Meier analysis, DM control did not affect time to mortality, limb salvage, wound healing, or loss of patency. However, multivariable proportional hazards analysis demonstrated increased risk of limb loss in patients with increasing HgbA1C (hazard ratio (HR) = 1.96 [1.42-2.80], P < 0.0001) or dialysis dependence (HR = 15.37 [3.44-68.73], P = 0.0003), increased risk of death in patients with worsening pulmonary status (HR = 1.70 [1.20-2.39], P = 0.0026), and increased risk of delayed wound healing in patients who are male (HR = 0.48 [0.29-0.79], P = 0.0495). No independent association existed between loss of patency with any of the variables we collected. CONCLUSIONS: Patients with uncontrolled DM, as defined by SVS reporting standards, do not have worse outcomes following revascularization for CLTI compared to patients with controlled DM. However, increasing HgbA1c is associated with a greater risk for early amputation. Before revascularization, specific attention to the level of glycemic control in patients with DM is important, even if DM is "controlled." In addition to aggressive attempts at improved glycemic control, those with elevated HgbA1c should receive careful education regarding their increased risk of amputation despite revascularization. Future work is necessary to incorporate the severity of DM into risk models of revascularization for the CLTI population.

The natural history of chronic limb-threatening ischemia after technical failure of endovascular intervention.

OBJECTIVES: The treatment for chronic limb-threatening ischemia (CLTI) has changed dramatically in the last few decades with a shift toward an endovascular-first approach and aggressive revascularization to achieve limb salvage. As the size of the CLTI population and intervention rates increase, patients will continue to experience technical failure (TF). Here, we describe the natural history of patients after TF of endovascular intervention for CLTI. METHODS: We conducted a retrospective cohort study of patients with CLTI who attempted endovascular intervention or bypass at our multidisciplinary limb salvage center from 2013 to 2019. Patient characteristics were collected according to the Society for Vascular Surgery's reporting standards. Primary outcomes included survival, limb salvage, wound healing, and revascularization patency. Product-limit Kaplan-Meier estimated survival functions for these outcomes, and between-group comparisons were made using Mantel-Cox log-rank nonparametric tests. RESULTS: We identified 242 limbs from 220 unique patients who underwent primary bypass (n = 30) or attempted endovascular intervention (n = 212) at our limb salvage center. Endovascular intervention was a TF in 31 (14.6%) limbs. After TF, 13 limbs underwent secondary bypass and 18 limbs were managed medically. Patients who experienced TF tended to be older (P < .001), male (P = .003), current tobacco users (P = .014), have longer lesions (P = .001), and have chronic total occlusions of target arteries (P < .001) as compared with those who experienced technical success. Furthermore, the TF group had worse limb salvage (P = .047) and slower wound healing (P = .028), but their survival was not different. Survival, limb salvage, and wound healing were not different in patients who received secondary bypass or medical management after TF. The secondary bypass group was older (P = .012) and had a lower prevalence of tibial disease (P = .049) than the primary bypass group and trended toward decreased survival, limb salvage, and wound healing (P = .059, P = .083, and P = .051, respectively). CONCLUSIONS: Increased age, male sex, current tobacco use, longer arterial lesions, and occluded target arteries are associated with TF of endovascular intervention. Limb salvage and wound healing are relatively poor after TF of endovascular intervention, but survival appears comparable with patients who experience technical success. Secondary bypass may not always rescue patients after TF, though our sample size limits statistical power. Interestingly, patients who received a secondary bypass after TF trended toward decreased survival, limb salvage, and wound healing compared with primary bypass.

Impact of an Ultrasound Demonstration on Vascular Surgery Interest in Preclinical Medical Students.

BACKGROUND: One strategy to address the impending shortage of vascular surgeons is to augment interest in the trainee pipeline. Endovascular procedures are unique to vascular surgery (VS) and endovascular simulations have proven effective at generating VS interest in the past. Like endovascular techniques, the use of ultrasound (US) testing in VS is unique among medical specialties. We hypothesized that an interactive US demonstration would increase VS interest in preclinical medical students. METHODS: We created a 5-point Likert scale survey assessing interest in VS, understanding of VS, likelihood to further investigate VS, choosing VS as a rotational elective, and pursuing VS shadowing and research opportunities. This survey was administered 1 day before and 1 day after the demonstration. Results were compared via paired t-test. A VS attending assisted by a senior registered vascular technologist covered physics, B-mode, continuous, pulsed wave, and color Doppler in an interactive, hands-on experience. Our dedicated US simulation laboratory enabled simultaneous interactive virtual broadcast and in-person learning. All first-year and second-year students at our medical school were invited via e-mail. RESULTS: Five hundred twelve students were invited, 39 attended, and 19 students who completed surveys were included. Sixty eight percent were female. Attendance at the US demonstration resulted in a significant increase in students' interest in vascular surgery (P = 0.012), understanding of vascular surgery (P < 0.001), likelihood to further investigate vascular surgery (P < 0.001), likelihood to choose a vascular surgery rotation (P < 0.001), and likelihood to pursue vascular surgery shadowing and research opportunities (P < 0.001). Although only 2 of 6 in-person attendees returned surveys, their increase in average response to all questions was higher than virtual attendees (+1.80 vs. +0.91, P = 0.043). CONCLUSIONS: Attending an interactive US demonstration significantly increased preclinical medical students' interest in understanding of VS. In-person and virtual attendance both had a positive impact. Such a demonstration may be an effective tool to recruit students. It is imperative that we continue innovating to address the future shortage of vascular surgeons.

Extra-Anatomic Bypass and Excision is Superior to Graft Salvage Attempts with Antibiotic Beads to Treat Vascular Graft Infections in the Groin.

BACKGROUND: This study aimed to determine if conventional extra-anatomic bypass and graft removal versus aggressive attempts at graft preservation have better survival and limb salvage in patients with localized groin wound infections of vascular grafts. METHODS: We conducted a retrospective review of 53 consecutive patients with vascular graft infections presenting in the groin. Treatment groups consisted of group 1 (extra-anatomic bypass and graft excision, n = 22) and group 2 (initial graft preservation attempts with utilization of antibiotic beads, n = 31). In group 2, patients underwent serial debridement and placement of antibiotic beads until culture-negative wounds were achieved. Significantly more patients underwent muscle flap coverage in group 2 (27/31) compared with group 1 (7/22; P < 0.001). Data collected included demographics, comorbidities, intraoperative details, and outcomes, including patency, limb salvage, mortality, and number of procedures. Continuous variables were examined with Student's t-test, and dichotomous variables were examined with chi-squared test. Linear and logistic regressions were used to analyze factors associated with outcomes, in addition to Kaplan-Meier analysis with log rank for actuarial analysis. RESULTS: Both groups were similar with respect to demographics. The overall Kaplan-Meier 1- and 3-year survival rates were 66.2% and 34.1%, with no statistically significant difference between groups. The Kaplan-Meier 1- and 3-year limb salvage rates were 68.8% and 36.6% for group 1 vs. 58.5% and 38.7% for group 2 (P = not significant [NS]). The 1- and 3-year primary patency rates were 71% and 71% in traditional group 1 vs. 72% and 56% in group 2 (P = NS). One-year and 3-year secondary patency rates in traditional group 1 were 83% and 71% vs. 85% and 61% in group 2 (P = NS). Patients in group 1 underwent fewer total procedures when compared with group 2 (2.3 ± 0.2 vs. 5.1 ± 0.7, P = 0.03). The late reinfection rate was significantly less in group 1 (4.5%) compared with group 2 (26%; P = 0.04). Freedom from reinfection at 1 and 3 years were 94% and 94% in traditional group 1 vs. 74% and 62% in group 2 (P = 0.03). Multivariable analysis showed a higher incidence of amputation in patients who suffered reinfection (n = 13, P = 0.049). There was a higher mortality in patients with septic shock (n = 10, P = 0.007) and reinfection (n = 13, P = 0.036). Reinfection was associated with the highest mortality (P = 0.03). CONCLUSIONS: Conventional graft excision with extra-anatomic bypass resulted in similar mortality when compared with aggressive attempts at graft preservation and trended toward improved limb salvage and patency. However, attempts at graft preservation with antibiotic beads resulted in a significantly higher reinfection rate and greater number of procedures, and therefore, this approach should be used very selectively.

In-situ bypass is associated with superior infection-free survival compared with extra-anatomic bypass for the management of secondary aortic graft infections without enteric involvement.

OBJECTIVE: The optimal revascularization modality following complete resection of aortic graft infection (AGI) without enteric involvement remains unclear. The purpose of this investigation is to determine the revascularization approach associated with the lowest morbidity and mortality using real-world data in patients undergoing complete excision of AGI. METHODS: A retrospective, multi-institutional study of AGI from 2002 to 2014 was performed using a standardized database. Baseline demographics, comorbidities, and perioperative variables were recorded. The primary outcome was infection-free survival. Descriptive statistics, Kaplan-Meier survival analysis, and univariate and multivariable analyses were performed. RESULTS: A total of 241 patients at 34 institutions from seven countries presented with AGI during the study period (median age, 68 years; 75% male). The initial aortic procedures that resulted in AGI were 172 surgical grafts (71%), 66 endografts (27%), and three unknown (2%). Of the patients, 172 (71%) underwent complete excision of infected aortic graft material followed by in situ (in-line) bypass (ISB), including antibiotic-treated prosthetic graft (35%), autogenous femoral vein (neo-aortoiliac surgery) (24%), and cryopreserved allograft (41%). Sixty-nine patients (29%) underwent extra-anatomic bypass (EAB). Overall median Kaplan-Meier estimated survival was 5.8 years. Perioperative mortality was 16%. When stratified by ISB vs EAB, there was a significant difference in Kaplan-Meier estimated infection-free survival (2910 days; interquartile range, 391-3771 days vs 180 days; interquartile range, 27-3750 days; P < .001). There were otherwise no significant differences in presentation, comorbidities, or perioperative variables. Multivariable Cox regression showed lower infection-free survival among patients with EAB (hazard ratio [HR], 2.4; 95% confidence interval [CI], 1.6-3.6; P < .001), polymicrobial infection (HR, 2.2; 95% CI, 1.4-3.5; P = .001), methicillin-resistant Staphylococcus aureus infection (HR, 1.7; 95% CI, 1.1-2.7; P = .02), as well as the protective effect of omental/muscle flap coverage (HR, 0.59; 95% CI, 0.37-0.92; P = .02). CONCLUSIONS: After complete resection of AGI, perioperative mortality is 16% and median overall survival is 5.8 years. EAB is associated with nearly a two and one-half-fold higher reinfection/mortality compared with ISB. Omental and/or muscle flap coverage of the repair appear protective.

Approaches to the Salvage of Axillary Bilateral Femoral Bypass in Patients with Claudication due to Demand Ischemia.

The axillary bilateral femoral bypass is often utilized as an alternative to in-line aortic reconstruction in patients with multiple medical comorbidities, who would be unable to tolerate open abdominal surgery with an aortic clamp, or patients with mycotic aneurysms, or infected grafts. Idealized fluid mechanics suggest that there would be equal flow in an axillary bilateral femoral bypass when compared to in-line reconstruction. However, in a non-idealized state, friction results in kinetic energy loss and decreased volume flow to the lower extremities in the longer, smaller diameter graft. Although older or less active people may tolerate the lower volume flow of a long segment extra-anatomic bypass, there is growing evidence that a subset of patients will be symptomatic from reduced flow volumes. Here we present 3 patients in whom symptomatic relief was achieved with the addition of a contralateral axillary femoral bypass and ligation of the previous femorofemoral component.

An Updated Physician Workforce Model Predicts a Shortage of Vascular Surgeons for the Next 20 Years.

BACKGROUND: Concern regarding the adequacy of the vascular surgery workforce persists. We aimed to predict future vascular surgery workforce size and capacity using contemporary data on the US population and number, productivity, and practice patterns of vascular surgeons. METHODS: The workforce size needed to maintain current levels of access was estimated to be 1.4 vascular surgeons/100,000 population. Updated population estimates were obtained from the US Census Bureau. We calculated future vascular surgery workforce needs based on the estimated population for every 10 years from 2020 to 2050. American Medical Association Physician Masterfile data from 1997 to 2017 were used to establish the existing vascular surgery workforce size and predict future workforce size, accounting for annual rates of new certificates (increased to an average of 133/year since 2013), retirement (17%/year), and the effects of burnout, reduced work hours, transitions to nonclinical jobs, or early retirement. Based on Medical Group Management Association data that estimate median vascular surgeon productivity to be 8,481 work relative value units (wRVUs)/year, excess/deficits in wRVU capacity were calculated based on the number of anticipated practicing vascular surgeons. RESULTS: Our model predicts declining shortages of vascular surgeons through 2040, with workforce size meeting demand by 2050. In 2030, each surgeon would need to increase yearly wRVU production by 22%, and in 2040 by 8%, to accommodate the workload volume. CONCLUSIONS: Our model predicts a shortage of vascular surgeons in the coming decades, with workforce size meeting demand by 2050. Congruence between workforce and demand for services in 2050 may be related to increases in the number of trainees from integrated residencies combined with decreases in population estimates. Until then, vascular surgeons will be required to work harder to accommodate the workload. Burnout, changing practice patterns, geographic maldistribution, and expansion of health care coverage and utilization may adversely affect the ability of the future workforce to accommodate population needs.

Treatment-Related Outcomes in Paget-Schroetter Syndrome-A Cross-Sectional Investigation.

OBJECTIVE: To investigate treatment-related outcomes, namely radiological clot resolution, post-thrombotic syndrome (PTS), and health related quality-of-life (HRQoL) scores, in children with Paget-Schroetter syndrome (PSS) undergoing multidisciplinary management, including anticoagulation and decompressive rib-resection surgery, with or without thrombolytic therapy. STUDY DESIGN: We identified all patients treated for PSS at our institution between the years 2010 and 2017. Baseline clinical and radiologic data were abstracted from medical records. Two validated survey instruments to quantify PTS and HRQoL were mailed to eligible patients. Standard statistical methods were used to summarize these measures. RESULTS: In total, 22 eligible patients were identified; 10 were treated with thrombolysis followed by anticoagulation and rib resection, and 12 were treated with anticoagulation and rib resection alone. Nineteen patients responded to the survey instruments. Median age at deep vein thrombosis diagnosis and survey completion were 16.3 and 20.4 years, respectively. Nineteen of 22 patients had thrombus resolution on radiologic follow-up. Fourteen of 19 survey respondents reported signs/symptoms of PTS of which the majority (12/14) reported mild PTS. Aggregate total, physical, and psychosocial HRQoL scores reported were 90.6, 96.7, and 93.3, respectively. Thrombolytic therapy was not associated with a significant improvement in radiologic, clinical or HRQoL outcomes. CONCLUSIONS: Most patients with PSS had complete thrombus resolution on imaging. Only 11% of survey respondents reported moderate PTS. The entire cohort reported excellent HRQoL scores. The role for thrombolytic therapy in the management of childhood PSS remains incompletely elucidated.

Variability in Noninvasive Vascular Laboratory Experience of Vascular Surgery Training Programs Based on Survey of Trainees Suggests the Need for a Standardized Curriculum.

BACKGROUND: Although a Registered Physician in Vascular Interpretation certification is required for vascular surgery board certification, no standardized noninvasive vascular laboratory (NIVL) curriculum for vascular surgery trainees exists. The purpose of this study is to investigate the NIVL experience of trainees and understand what helps them feel well prepared. METHODS: Current trainees in all 0 + 5 and 5 + 2 vascular surgery training programs (114) were surveyed. The most complete survey from each program was included in the analysis. Programs were divided into those in which trainees felt well prepared (WP) and those in which trainees felt unprepared (UP) for the Physician Vascular Interpretation (PVI) examination. Responses for the 2 groups were compared. RESULTS: Responses from 61 of the 114 programs (53.5%) were analyzed. Most programs devote <0.5 days per week to the NIVL (52.5%), assign lectures and textbook reading (55.7% and 47.5%), and provide hands-on experience with vascular technologists (60.7%) and attending surgeons (52.5%). Respondents from 15 programs (24.6%) took a PVI examination review course. The first-time PVI examination pass rate was 92.9% (13 of 14 trainees). The WP group reported higher rates of a structured curriculum for the NIVL (100% vs. 33.3%, P = 0.0001), one-on-one time with vascular technologists (78.6% vs. 44.4%, P = 0.05), mandatory lectures (78.6% vs. 33.3%, P = 0.004), and assigned articles (64.3% vs. 11.1%, P = 0.002). CONCLUSIONS: There is wide variation in NIVL experience among vascular surgery training programs. Many trainees feel unprepared for the PVI examination, especially those without a structured curriculum. These results suggest that a structured NIVL curriculum that includes dedicated time with vascular technologists, lectures, and articles should be established.

Common carotid artery end-diastolic velocity and acceleration time can predict degree of internal carotid artery stenosis.

OBJECTIVE: Whereas duplex ultrasound parameters for predicting internal carotid artery (ICA) stenosis are well defined, the use of common carotid artery (CCA) Doppler characteristics to predict ICA stenosis when the ICA cannot be insonated directly or accurately because of anatomy, calcification, or tortuosity has not been studied. The objective of this study was to identify CCA Doppler parameters that may predict ICA stenosis. METHODS: We reviewed all patients at our institution who underwent carotid duplex ultrasound (CDU) from 2008 to 2015 and also had a comparison computed tomography, magnetic resonance, or catheter angiogram. We excluded patients whose CDU examination did not correlate with the comparison study, those whose arteries were not visualized on the comparison study, and those with complete occlusion of the CCA. We collected CCA peak systolic velocity (PSV), end-diastolic velocity (EDV), and acceleration time (AT) in addition to CDU and comparison imaging interpretation of degree of stenosis. A multivariate model was used to identify predictors of ICA stenosis. RESULTS: There were 99 CDU examinations with corresponding comparison imaging included. For every increase of 10 cm/s in EDV in the CCA, the odds of a >50% ICA stenosis being present vs a ≤50% ICA stenosis decreased by 37% (odds ratio [OR], 0.63; 95% confidence interval [CI], 0.41-0.97; P = .03). For every increase of 10 cm/s in EDV in the CCA, the odds of a 70% to 99% ICA stenosis being present vs a ≤50% ICA stenosis decreased by 48% (OR, 0.52; 95% CI, 0.28-0.94; P = .03). A CCA EDV of 19 cm/s or below was associated with a 64% probability of a 70% to 99% ICA stenosis. For every 50-millisecond increase in AT in the CCA, the odds of a >50% stenosis being present vs a ≤50% ICA stenosis increased by 56% (OR, 1.56; 95% CI, 1.03-2.35; P = .04). A CCA AT of 80 milliseconds or above was associated with a 69% probability of a >50% ICA stenosis. There was no correlation between CCA PSV and ICA stenosis. CONCLUSIONS: CCA EDV and AT are independent predictors of ICA stenosis and may be used in the setting of patients whose ICA cannot be directly insonated or when standard duplex ultrasound parameters of ICA PSV, EDV, or ICA/CCA ratio conflict.

Isolated Great Saphenous Vein Thrombus Is Associated with High Rates of Complications regardless of Management.

BACKGROUND: Isolated great saphenous vein thrombus (GSVT) is generally regarded as benign, and treatment is heterogeneous. Complications include thrombus propagation, new saphenous vein thrombosis, deep vein thrombosis (DVT), pulmonary embolism (PE), and symptom persistence. Our objective was to review our institution's experience with isolated GSVT to understand its natural history, the frequency of complications, real-world treatment, and the impact of proximity to the saphenofemoral junction (SFJ), on the rate of complications. METHODS: Records of patients who had lower extremity venous duplex (LEVD) demonstrating GSVT without concomitant DVT between July 2008 and June 2014 were reviewed. Demographic, medical, management, outcomes, and follow-up LEVD data were collected. RESULTS: Of 605 patients with acute GSVT, 67 limbs in 61 patients with isolated GSVT were the study group; 14.8% of patients had a hypercoagulable state, 31.1% had prior GSVT or DVT, and 23.0% of patients had malignancy; 28.4% of GSVT were observed, 13.4% were treated with aspirin/NSAIDs, and 58.2% were anticoagulated; 38.8% of limbs remained symptomatic following treatment at a mean follow-up period of 761 days; 37 limbs had GSVT <5 cm of the SFJ (group 1), and 30 had GSVT >5 cm from the SFJ (group 2). Seven patients developed PE, all in group 1 (P = 0.02). Twenty-nine limbs (43.3%) had follow-up LEVD at a mean of 23 days. In this subset, 13 patients at the initial scan (44.8%) had thrombus <5 cm of the SFJ (group 1) and 16 (55.2%) had thrombus >5 cm from the SFJ (group 2). Five limbs (17.2%) had GSVT propagation/new superficial vein thrombosis (SVT), and 6 (20.7%) developed new DVT. There was no GSVT propagation/new SVT in group 1, whereas 5 limbs (31.2%) had GSVT propagation/new SVT in group 2 (P = 0.048). DVT occurred in 2 limbs (15.3%) in group 1 and 4 limbs (25%) in group 2. CONCLUSIONS: Isolated GSVT tends to affect patients with hypercoagulable states, prior venous thromboembolism, malignancy, or recent surgery. Management is heterogeneous, and type of treatment does not seem to affect outcomes. Patients with GSVT have significant risk of persistent symptoms, recurrence, DVT, and PE. GSVT within 5 cm of the SFJ seemed to be associated with an increased rate of PE. GSVT more than 5 cm from the SFJ seemed to be associated with propagation/new SVT. Proximity to the SFJ did not impact occurrence of DVT.

Popliteal Artery Cystic Adventitial Disease: Early Lessons in Treatment.

BACKGROUND: We present 6 patients who had operative repair of symptomatic popliteal cystic adventitial disease (pCAD). Developmental theories for pCAD and surgical alternatives are presented. METHODS: All patients who had repair of pCAD over the past 3 years are included. RESULTS: Three patients had cyst excision alone, whereas the remaining 3 had cyst and artery excision with interposition vein grafting. Cyst recurrence occurred in 2 patients who had cyst excision alone. Four of the patients had a patent communication between the cyst and the joint capsule. CONCLUSIONS: Our small series suggests that the articular (synovial) theory of development may be the most likely and that cyst and artery excision with interposition vein grafting may be preferred over cyst excision alone.

Quantification of abdominal aortic aneurysm stiffness using magnetic resonance elastography and its comparison to aneurysm diameter.

OBJECTIVE: Abdominal aortic aneurysm (AAA) wall stiffness has been suggested to be an important factor in the overall rupture risk assessment compared with anatomic measure. We hypothesize that AAA diameter will have no correlation to AAA wall stiffness. The aim of this study is to (1) determine magnetic resonance elastography (MRE)-derived aortic wall stiffness in AAA patients and its correlation to AAA diameter; (2) determine the correlation between AAA stiffness and amount of thrombus and calcium; and (3) compare the AAA stiffness measurements against age-matched healthy individuals. METHODS: In vivo abdominal aortic MRE was performed on 36 individuals (24 patients with AAA measuring 3-10 cm and 12 healthy volunteers), aged 36 to 78 years, after obtaining written informed consent under the approval of the Institutional Review Board. MRE images were processed to obtain spatial stiffness maps of the aorta. AAA diameter, amount of thrombus, and calcium score were reported by experienced interventional radiologists. Spearman correlation, Wilcoxon signed rank test, and Mann-Whitney test were performed to determine the correlation between AAA stiffness and diameter and to determine the significant difference in stiffness measurements between AAA patients and healthy individuals. RESULTS: No significant correlation (P > .1) was found between AAA stiffness and diameter or amount of thrombus or calcium score. AAA stiffness (mean 13.97 ± 4.2 kPa) is significantly (P ≤ .02) higher than remote normal aorta in AAA (mean 8.87 ± 2.2 kPa) patients and in normal individuals (mean 7.1 ± 1.9 kPa). CONCLUSIONS: Our results suggest that AAA wall stiffness may provide additional information independent of AAA diameter, which may contribute to our understanding of AAA pathophysiology, biomechanics, and risk for rupture.

Axillary-Femoral Bypass May Provide Inadequate Distal Perfusion Compared with In-Line Large Diameter Aortic Reconstruction.

Axillary-femoral bypass is sometimes performed for complex aortoiliac occlusive disease in patients unfit for aortic surgery or in those with aortic infection. Typically, older patients with medical comorbidities that commonly accompany atherosclerotic or aneurysmal disease are involved and can tolerate the theoretic risk of limited flow volume associated with long, small diameter, axillary-femoral grafts. However, a subset of younger, healthier, more vigorous patients outside the typical atherosclerotic or aneurysmal demographic occasionally come to axillary-femoral bypass and may experience symptoms of distal hypoperfusion if flow volumes cannot meet demand. We present a series of patients with primary aortic infection treated with aortic ligation and axillary-femoral bypass, who then progressed to symptoms of visceral, spinal, or extremity ischemia from inadequate distal perfusion.

Reimbursement Policies for Carotid Duplex Ultrasound that are Based on International Classification of Diseases Codes May Discourage Testing in High-Yield Groups.

BACKGROUND: To curb increasing volumes of diagnostic imaging and costs, reimbursement for carotid duplex ultrasound (CDU) is dependent on "appropriate" indications as documented by International Classification of Diseases (ICD) codes entered by ordering physicians. Historically, asymptomatic indications for CDU yield lower rates of abnormal results than symptomatic indications, and consensus documents agree that most asymptomatic indications for CDU are inappropriate. In our vascular laboratory, we perceived an increased rate of incorrect or inappropriate ICD codes. We therefore sought to determine if ICD codes were useful in predicting the frequency of abnormal CDU. We hypothesized that asymptomatic or nonspecific ICD codes would yield a lower rate of abnormal CDU than symptomatic codes, validating efforts to limit reimbursement in asymptomatic, low-yield groups. MATERIAL AND METHODS: We reviewed all outpatient CDU done in 2011 at our institution. ICD codes were recorded, and each medical record was then reviewed by a vascular surgeon to determine if the assigned ICD code appropriately reflected the clinical scenario. CDU findings categorized as abnormal (>50% stenosis) or normal (<50% stenosis) were recorded. Each individual ICD code and group 1 (asymptomatic), group 2 (nonhemispheric symptoms), group 3 (hemispheric symptoms), group 4 (preoperative cardiovascular examination), and group 5 (nonspecific) ICD codes were analyzed for correlation with CDU results. RESULTS: Nine hundred ninety-four patients had 74 primary ICD codes listed as indications for CDU. Of assigned ICD codes, 17.4% were deemed inaccurate. Overall, 14.8% of CDU were abnormal. Of the 13 highest frequency ICD codes, only 433.10, an asymptomatic code, was associated with abnormal CDU. Four symptomatic codes were associated with normal CDU; none of the other high frequency codes were associated with CDU result. Patients in group 1 (asymptomatic) were significantly more likely to have an abnormal CDU compared to each of the other groups (P < 0.001, P < 0.001, P = 0.020, P = 0.002) and to all other groups combined (P < 0.001). CONCLUSIONS: Asymptomatic indications by ICD codes yielded higher rates of abnormal CDU than symptomatic indications. This finding is inconsistent with clinical experience and historical data, and we suggest that inaccurate coding may play a role. Limiting reimbursement for CDU in low-yield groups is reasonable. However, reimbursement policies based on ICD coding, for example, limiting payment for asymptomatic ICD codes, may impede use of CDU in high-yield patient groups.

Tibial osteochondroma inducing popliteal artery compression.

Compression of the neurovascular contents of the popliteal fossa is a rare condition that leads to exercise-induced pain and paresthesias in young athletes. Most frequently, it is caused by musculotendinous abnormalities resulting in popliteal entrapment syndrome. Bony abnormalities rarely are implicated but can produce symptoms that mimic popliteal entrapment syndrome. We present a patient with a tibial metaphysis osteochondroma inducing popliteal artery compression that was relieved after resection.

Cerebral oxygenation and processed EEG response to clamping and shunting during carotid endarterectomy under general anesthesia.

Clamping and shunting during carotid endarterectomy (CEA) surgery causes changes in cerebral blood flow. The purpose of this study was to assess and compare, side by side, the cerebral oxygenation (rSO2) and processed electroencephalogram (EEG) response bilaterally to carotid artery clamping and shunting in patients undergoing CEA under general anesthesia. With institutional approval and written informed consent, patients undergoing CEA under general anesthesia and routine carotid artery shunting were recorded bilaterally, simultaneously and continuously with an rSO2 and processed EEG monitor. The response of the monitors during carotid artery clamping and shunting were assessed and compared between monitors and bilaterally within each monitor. Sixty-nine patients were included in the study. At clamping the surgical-side and contralateral-side rSO2 dropped significantly below the baseline incision value (-17.6 and -9.4% respectively). After shunting, the contralateral-side rSO2 returned to baseline while the surgical-side rSO2 remained significantly below baseline (-9.0%) until the shunt was removed following surgery. At clamping the surgical-side and contralateral-side processed EEG also dropped below baseline (-19.9 and -20.6% respectively). However, following shunt activation, the processed EEG returned bilaterally to baseline. During the course of this research, we found the rSO2 monitor to be clinically more robust (4.4% failure rate) than the processed EEG monitor (20.0% failure rate). There was no correlation between the rSO2 or processed EEG changes that occurred immediately after clamping and the degree of surgical side stenosis measured pre-operatively. Both rSO2 and processed EEG respond to clamping and shunting during CEA. Cerebral oximetry discriminates between the surgical and contralateral side during surgery. The rSO2 monitor is more reliable in the real-world clinical setting. Future studies should focus on developing algorithms based on these monitors that can predict clamping-induced cerebral ischemia during CEA in order to decide whether carotid artery shunting is worth the associated risks. From the practical point of view, the rSO2 monitor may be the better monitor for this purpose.

Gluteal and thigh compartment syndrome after open abdominal aortic aneurysm repair.

Although compartment syndrome (CS) can occur in any myofascial compartment, the thigh and buttock are among the least common. CS is characterized by an increase in pressure of a myofascial compartment that results in a reduction of capillary blood flow and myonecrosis. Although >75% of cases of CS occur after long bone fractures, acute CS can also occur from nontraumatic and vascular etiologies. We report a case of gluteal and thigh CS resulting from ischemia-reperfusion injury after abdominal aortic aneurysm repair and left common iliac artery bypass.