Faculty Bibliography

OBJECTIVE:Wound complications after major lower extremity amputations are a cause of significant morbidity in vascular surgery patients. Recent publications have demonstrated the efficacy of the closed incision negative pressure dressing at preventing surgical site infections (SSIs); however, there are limited data on its use in major lower extremity amputations. This study sought to assess if closed incision negative pressure wound therapy (NPWT) would reduce the risk of complications as compared to a standard dressing in patients with peripheral vascular disease undergoing major lower extremity amputation. METHODS:system (Acelity L.P. Inc., San Antonio, TX, USA) was applied intraoperatively at the discretion of the operating surgeon and removed 5 to 7 days postoperatively. The standard group received a non-adherent dressing with an overlying compression dressing. Amputation incisions were assessed and wound complications were recorded. Student's t-test and two-sample proportion z-test were used for statistical analysis. A P value < .05 was considered statistically significant. RESULTS:For comorbidities, there was a higher incidence of tobacco use in the NPWT as compared to the standard group (44% vs. 13%; P = .011), as well as trends towards increased prior amputations, anemia, hyperlipidemia, and chronic obstructive pulmonary disorder in the NPWT group. For risk factors, there were more dirty wounds in the NPWT as compared to the standard group (52% vs. 26%; P = .046). For outcomes, there were fewer wound complications in the NPWT as compared to the standard group (13% vs. 39%; P = .037). The types of wound-related complications in the NPWT group included one wound dehiscence with a deep SSI, one superficial SSI and one incision line necrosis. In the standard group, there were 4 wound dehiscences with deep SSI, 3 superficial SSIs, 4 incision line necroses and 1 stump hematoma. The rates of perioperative mortality and amputation revision did not differ significantly between the NPWT and the standard group (3% vs. 4% and 4.3% vs. 10%, respectively). CONCLUSIONS:Closed incision negative pressure wound therapy may decrease the incidence of wound complications in vascular patients undergoing major lower extremity amputation. This held true even amongst a population that was potentially at higher risk. This therapy may be considered for use in lower extremity major amputations.

Objective: Whereas clopidogrel is effective at decreasing cardiovascular events in patients with peripheral artery disease, a substantial number of events continue to occur. This study investigated the variability in response to clopidogrel and its relationship with clinical outcomes.
Method(s): There were 300 patients enrolled in the Platelet Activity in Vascular Surgery and Cardiovascular Events (PACE) study before lower extremity revascularization, of whom 119 were receiving clopidogrel. Platelet aggregation was measured in response to adenosine diphosphate (ADP) 2M immediately before revascularization. Patients were observed longitudinally for a median follow-up of 18 months. The primary end point was major adverse limb events (MALEs), defined by major amputation or reoperation of the affected limb. Patients were stratified into groups according to the percentage ADP-induced aggregation at 300 seconds (<50% aggregation, normal responder; >=50% aggregation, poor responder).
Result(s): Overall, the median age was 70 years (62-76 years), and 39.5% were female. Thirty-six (30.3%) patients had a MALE event (15 major amputation and 25 major reoperation); 60 patients underwent open or hybrid operations, and 50 patients underwent endovascular procedures. The remaining nine patients had no interventions. Of the group of 119 patients, 97 patients were taking aspirin. Overall, median aggregation to ADP 2M was 22.5% (Q1-Q3, 10%-50%), and 27 patients (26%) were clopidogrel nonresponders. Baseline aggregation was higher in patients who went on to develop a MALE than in those without a MALE (43% vs 20%; P =.018). Patients with aggregation > median (22.5%) were more likely to experience a MALE than were patients with aggregation < median (69% vs 31%; hazard ratio [HR], 2.71; 95% confidence interval [CI], 1.23-5.98; P =.013). After multivariable adjustment for age, sex, race/ethnicity, body mass index, diabetes, coronary artery disease, and aspirin, aggregation > median was associated with MALEs (adjusted HR, 2.67; 95% CI, 1.18-6.01; P =.018). When stratified by established cutoffs for responsiveness to clopidogrel (50% aggregation), 27 (26%) patients were poor responders. Poor responders were more likely to experience MALEs than normal responders (59% vs 41%; HR, 2.33; 95% CI, 1.11-4.89; P =.026). After multivariable adjustment, poor responder status trended toward an increased risk of MALE compared with a normal responder (adjusted HR, 2.18; 95% CI, 1.00-4.78; P =.051).
Conclusion(s): Among patients undergoing lower extremity revascularization, poor response to clopidogrel is associated with increased risk for major adverse limb events. Preoperative screening to ensure therapeutic clopidogrel response should be considered in these patients.
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The novel coronavirus 2019 (SARS-CoV-2) was first identified in January 2020 and has since evolved into a pandemic affecting >200 countries. The severity of presentation is variable and carries a mortality between 1% and 3%. We continue to learn about the virus and the resulting acute respiratory illness and hypercoagulability; however, much remains unknown. In our early experience in a high-volume center, we report a series of four cases of acute peripheral artery ischemia in patients with COVID-19 in the setting of elevated D-dimer levels.

OBJECTIVE/UNASSIGNED:Patients who present acutely with a femoral deep vein thrombosis (DVT) diagnosed by ultrasound are often treated with anticoagulation and instructed to follow-up electively. This study sought to assess whether obtaining axial imaging of the central venous system results in the identification of additional iliocaval pathology warranting treatment. METHODS/UNASSIGNED:This study was a retrospective review of a prospectively maintained registry from November 2014 through April 2017 with follow-up through March 2020. Consecutive patients with a diagnosis of femoral DVT diagnosed by ultrasound were evaluated; those who underwent axial imaging of the iliocaval system (Group A) were compared to those who did not undergo imaging of the central veins (Group B). The primary outcome was the performance of any percutaneous central venous intervention. Secondary outcomes included the extent of DVT identified on duplex and after axial imaging, follow-up duplex patency and persistence of severe symptoms. RESULTS/UNASSIGNED:Eighty patients presented with an ultrasound diagnosis of a femoral vein DVT. Mean follow-up was 551 ± 502 days. Group A comprised 24 patients (30%) and Group B comprised 56 patients (70%). Baseline demographics did not differ significantly between the 2 groups. After duplex imaging, Group A exhibited an increased prevalence of DVT in the common femoral vein. After central imaging, Group A exhibited an increased prevalence of DVT in the iliocaval veins. The number of patients who underwent invasive treatment differed significantly between the 2 groups, Group A 16/24 (67%) vs. Group B 9/56 (16%), P < 0.0001. The number of patients that demonstrated duplex patency and had persistent symptoms on follow-up did not differ significantly. CONCLUSIONS/UNASSIGNED:Patients with an ultrasound diagnosis of femoral DVT may have additional iliocaval pathology warranting intervention. Well-selected imaging of the central veins may reveal a more complete picture, potentially altering management.

OBJECTIVE:The objective of this study was to evaluate the efficacy, durability, and safety of radiofrequency ablation (RFA) and endovenous laser ablation (EVLA) of the great saphenous vein (GSV) and small saphenous vein (SSV) to treat symptomatic venous reflux in patients receiving therapeutic anticoagulation. METHODS:tests, Fisher exact test, Kaplan-Meier curves, and Cox proportional hazard modeling. RESULTS:There were 100 procedures performed in 65 patients receiving anticoagulation and 127 procedures in 89 control patients. Mean follow-up time was 467 days. The most common indications for anticoagulation were atrial fibrillation (52%), remote DVT (29%), and mechanical heart valves (8%). Patients receiving anticoagulation were on average older (67 years vs 52 years), were more likely to be male (51% vs 27%), and had higher rates of coronary disease (9% vs 0%) and hypertension (55% vs 20%), although they were more likely to have never smoked (86% vs 69%). There were 127 RFA procedures (56%) and 100 EVLA procedures (44%); 189 procedures treated the GSV or its tributaries (83%), and 38 treated the SSV (17%). At 1 year, the target vessel remained ablated after 96% of procedures performed with anticoagulation and in 99% of controls; at 18 months, rates were 92% vs 95% (P = .96). Rates of persistent ablation did not differ significantly by vessel treated (P = .28), EVLA vs RFA (P = .36), or use of antiplatelet therapy (P = .92). One patient had bleeding from a phlebectomy site 2 days postprocedurally when supratherapeutic on warfarin; this was controlled with pressure. DVT in the ipsilateral leg occurred within 90 days after 1 of 100 (1%) procedures in patients receiving anticoagulation and 2 of 127 (1.6%) procedures in control patients; endothermal heat-induced thrombosis rates were similarly 1 of 100 (1%) procedures in patients receiving anticoagulation and 1 of 127 (0.8%) in control patients. CONCLUSIONS:This is the largest series to date reporting >30-day follow-up for patients undergoing venous ablation procedures while receiving anticoagulation and the longest follow-up reported of any series. Durability, safety, and efficacy of vein ablation in patients receiving anticoagulation are comparable to those in control patients. Anticoagulation should not be considered a contraindication to endothermal ablation of the GSV or SSV for symptomatic venous reflux.

OBJECTIVE:Prior authorization (PA) is a process used by payers for safety and cost savings purposes, but it has received criticism for being time-consuming and costly because of administrative burden. Our study evaluated efficacy of PA applied to in-office lower extremity superficial venous procedures. METHODS:All in-office lower extremity venous procedures scheduled to be performed at our institution in 2017 were included in the study. Variables of interest were type of procedure, initial PA status (approved or denied), rationale for the decision, and final status after appeal. Cost analysis was performed using Centers for Medicare and Medicaid Services allowable rates to approximate billing and reimbursement data (proprietary) as well as calculated using industry averages. RESULTS:For 2017, of 1959 procedures scheduled, 57.9% (n = 1134) required PA. Of these, only 6.1% (n = 69) received initial PA denial, and nearly 40% of the denials (n = 27) were overturned after appeal. Of the 42 denials that were upheld, 15 resulted in cancellations; the remainder were performed by patient self-pay (n = 11) or by the provider pro bono (n = 16). Overturned denials were a result of either submission of incomplete clinical data on initial PA request or insufficient documentation of clinical necessity. When Centers for Medicare and Medicaid Services allowable rates were applied for cost analysis, the denials resulted in <$60,000 payer savings. Administrative expenses totaled >$110,000 when industry standards were applied, which far exceeds any calculated payer savings using the same methods. The 15 denials resulting in procedure cancellations (1.3% of all PAs) could be considered a net savings to the health care system but only approximated a mere $30,000. CONCLUSIONS:Our study demonstrates that PA is not a cost-effective measure for utilization management of outpatient superficial venous procedures when surgeon practices are already well aligned with insurance guidelines. For these physicians and physician groups, the administrative cost associated with the PA process exceeds the savings seen by the insurance companies.

OBJECTIVE:MATERIAL AND METHODS: This is a single tertiary care center retrospective cohort study of all consecutive inpatients diagnosed with acute VTE from June 2015 to December 2015. During this period, 4495 patients underwent venous duplex examination (622 UE and 3873 LE), identifying 83 inpatient DVTs. Chronic DVT as well as those diagnosed in the outpatient population were excluded. DVTs were classified as either provoked or unprovoked. Provoked DVT were defined as the presence of any of the following factors within 30 days prior to diagnosis: major surgery, immobilization (greater than 3 days of bedrest), trauma, infection requiring antibiotics, central venous access, pregnancy, and/or hormonal medication use. Inpatient pulmonary embolisms (PE) detected on chest computed tomography (CT) were also evaluated during this time frame. Patient data were collected including age, gender, race, lifestyle factors, comorbidities, VTE risk factors, symptomatology at presentation, management including anticoagulation choice and filter placement if applicable, as well as discharge disposition. Statistical analysis was performed using GraphPad Prism 8.0 (GraphPad Software, San Diego, California, USA), and a threshold p-value of < 0.05 set for significance. RESULTS:During the study period, 83 DVTs (48 LEDVT, 35 UEDVT) and 24 PE were identified in 96 inpatients. Of these DVTs, 77.1% of these were defined as provoked. Eleven patients had simultaneous DVT and PE, and thirteen patients had PE with presumed occult pelvic or LEDVT. UEDVT patients had a higher proportion of comorbidities than LEDVT patients: coronary artery disease (25.7% vs. 13.1%, p=0.16), congestive heart failure (20% vs. 6.6%, p=0.09), as well as a trend toward higher incidence of malignancy (60% vs. 42.6%, p=0.13). Of provoked VTE, UEDVT correlated more significantly with central venous catheters (88.4% vs. 12.5%, p=<0.0001), but was less commonly associated with prolonged bed rest (19.2% vs. 39.5%, p=0.11). PE was diagnosed in 24/96 (25%) of the study population. Patients with LEDVT were found to have a significantly higher incidence of PE compared to those with UEDVT (34.4% vs. 8.6%, p=0.006). Same-admission mortality for patients with VTE was 13/96 (13.5%). Of these, patients with UEDVT had significantly higher all-cause mortality than patients with LEDVT (28.5% vs. 4.9%, p=0.004). When catheter-related UEDVT were excluded, there remained a significant difference in mortality between non-catheter related UEDVT and LEDVT (33.3% vs. 4.9% p=0.0119). CONCLUSIONS:This study demonstrates a high prevalence of UEDVT in hospitalized patients who experience VTE. Despite a lower incidence of synchronous PE, patients with UEDVT had a higher prevalence of significant medical comorbidities and higher all-cause mortality on the index hospital admission.

Objective: The purpose of this study was to evaluate the effect of an advanced pneumatic compression device (APCD) on improving symptoms and quality of life in patients with lower extremity lymphedema.
Method(s): A total of 178 patients with lower extremity lymphedema were prospectively enrolled in this multicenter study (four Veterans Administration Hospitals) from 2016 to 2019. This study represents analysis of the first 74 patients who have completed 52 weeks of APCD treatment. Demographics and patient characteristics (limb girth, body mass index, and stage of lymphedema) were collected at baseline. Primary end points included both generic quality of life assessment (36-Item Short Form Health Survey) and a disease-specific measure (Lymphedema Quality of Life questionnaire) at 12, 24, and 52 weeks of follow-up. Secondary end points compared changes in limb circumference and skin assessment (lymphedema stage) at each follow-up interval visit. Complications including cellulitis episodes, number of clinic visits, and hospital admissions associated with cellulitis were recorded for the 52 weeks before enrollment and compared with similar events within the 52 weeks of treatment with APCD.
Result(s): Patient demographics were as follows: mean age, 67.0 +/- 11.4 years; male sex (n = 70); body mass index, 32.8 +/- 5.9 kg/m². Most patients had secondary lymphedema (n = 71 [95.9%]), of which the most common cause was chronic venous insufficiency (n = 53 [71.6%]). The majority of patients presented with stage 1 or stage 2 lymphedema (n = 70 [94.6%]); There was a significant decrease in limb girth noted at 12 weeks compared with baseline (28.1 vs 27.3 cm; P =.002), which then plateaued for the remainder of the study period. The 36-Item Short Form Health Survey showed a trend toward quality of life improvement in all areas at 52 weeks (physical component, 39.9 vs 41.7 [P =.1]; mental component, 49.3 vs 51.3 [P =.2]). Lymphedema Quality of Life questionnaire leg scores showed significant continued improvement at each time point (P <.0001). Of the 74 patients, 18 (24.3%) had a history of cellulitis in the 52 weeks before enrollment compared with 7 (9.5%) after 1 year of APCD treatment (P =.01). Among this cellulitis cohort, there was a significant decrease in number of episodes per patient (0.3 vs 0.1; P =.01), total clinic visits (19 vs 6; P =.0003), number of clinic visits per patient (2.2 vs 0.7; P =.06), and number of hospital admissions per patient (0.05 vs 0.1; P =.047).
Conclusion(s): APCD for treatment of lymphedema appears to result in a continued linear improvement in quality of life at least up to 1 year beyond the initial clinical benefit of decreased limb girth. A significant decrease in the number of episodes of cellulitis as well as fewer associated clinic and hospital visits may explain the noted improvement in quality of life for patients and can represent significant cost savings to the health care system.
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PURPOSE/OBJECTIVE:To describe our clinical experience in using a system with a 4 Fr catheter profile for endovascular creation of arteriovenous fistulae (AVF) in hemodialysis patients. METHODS:This was a multi-operator, single center, single-arm, prospective study intended to evaluate safety and efficacy of a 4 Fr endovascular AVF (endoAVF) system for the creation of vascular access in hemodialysis patients. The study was performed after institutional review board approval at Italian Hospital (Asuncion, Paraguay). Patients were followed at regular intervals through 6 months to determine procedural, maturation, and cannulation success as well as intervention rate and patency. RESULTS:From May to November 2016, 32 patients underwent the endoAVF procedure with no device-related adverse events. An endoAVF was successfully created in the proximal forearm for all 32 patients (20 between the radial artery and radial vein; 12 between the ulnar artery and ulnar vein). Wrist access was used for 72% (23/32) of the procedures for the arterial catheter and 59% (19/32) of the procedures for the venous catheter. The device successfully created an endoAVF in every patient for a technical success rate of 100% (32/32). The device- or procedure-related serious adverse event rate was 3% (1/32); one patient experienced a venous guidewire perforation successfully managed with a stent graft. Primary and cumulative patency rates through 6 months were 83% and 87%, respectively, with an intervention rate of 0.21 per patient-year. Physiological suitability, as defined by target flow rates ≥500 ml/min and cannulation vessel diameters ≥4 mm, were achieved in 91% (29/32) of patients by 90 days. Successful 2-needle cannulation was achieved in 78% (21/27) by 90 days, with mean time to cannulation of 43 ± 14 days. Functional cannulation, as defined by successful 2-needle cannulation for two-thirds of the dialysis sessions within 1 month, was achieved in 95% (20/21) of the patients that were successfully cannulated for an overall rate of 74% (20/27). All patients that achieved functional cannulation had their central venous catheters (CVCs) removed before the 90-day follow up for a CVC removal rate of 74% (20/27). CONCLUSIONS:The 4 Fr endoAVF system allowed for multiple access and fistula creation site options to tailor the procedure to individual patient anatomy. Further, the outcomes are comparable to previous generation endoAVF technology, with a potentially improved safety profile due to the use of arteries at the wrist for access.