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.

Background: Severe presentations of chronic venous insufficiency may result from reflux or obstruction at the deep venous, perforator or superficial venous levels. Iliofemoral venous stenting may be used to address central venous obstruction, but its effect on deep venous reflux remains unclear. The purpose of this study was to evaluate the effect of iliac vein stenting on femoropopliteal deep vein reflux with the hypothesis that sonographic evidence of deep vein reflux would remain absent or improve following iliac vein stenting.
Method(s): This study was a retrospective review of patients undergoing iliofemoral venous stenting from 2013-2020. Patients were divided into two cohorts based on the preprocedural presence (Group A) or absence (Group B) of femoropopliteal reflux. Baseline patient variables were collected including age, gender, CEAP, presence of concomitant superficial or perforator reflux, DVT history, and additional venous intervention(s). The primary outcome evaluated was the persistent absence or the resolution of deep vein reflux on the latest venous duplex ultrasound follow-up. Other outcomes included follow-up CEAP classification as well as need for secondary deep venous interventions.
Result(s): There were 275 consecutive patients who underwent iliofemoral venous stenting. Of those, 58 presented with deep vein reflux (Group A), and the remaining did not (Group B). When comparing Group A and Group B, patients in Group A had a higher likelihood of prior DVT (P =.0001) as well as higher frequency of venous ablation (Table). The remaining demographics did not differ significantly between the two groups. In Group A, deep vein reflux resolved in follow-up in 17/51 patients (P =.0001). In Group B, deep vein reflux developed on follow-up in 6/217 patients. CEAP appeared to improve from preintervention (C0, 1.1%; C1, 0.4%; C2, 1.8%; C3, 41.4%; C4, 24.9%; C5, 5.9%; and C6, 24.5%) to latest follow-up (C0, 4.9%; C1, 1.9%; C2, 5.7%; C3, 34.2%; C4, 22.8%; C5, 17.1%; and C6, 13.3%).
Conclusion(s): For patients who undergo iliofemoral vein stenting, deep vein reflux may improve if present initially, and is unlikely to develop if not present prior to intervention. A cohort of patients maintained persistent deep vein reflux, and these warrant further evaluation. Prospective studies are required to corroborate the safety, efficacy and durability of iliofemoral venous stenting in patients with deep vein reflux. [Formula presented]
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Thrombosis is a major concern in respiratory infections. Our aim was to investigate the magnitude and duration of risk for arterial and venous thrombosis following discharge after respiratory infection. Patients with respiratory infections were identified using the United States Nationwide Readmission Database from 2012 to 2014. Patients admitted with asthma or cellulitis served as comparators. Readmissions for acute myocardial infarction (MI) and venous thromboembolism (VTE) were evaluated at 30 to 180 days. The likelihood of a first thrombotic event after discharge was compared with a 30-day period prior to hospitalization. Among 5,271,068 patients discharged after a respiratory infection, 0.56% and 0.78% were readmitted within 30-days with MI and VTE, respectively. Relative to asthma and cellulitis, respiratory infection was associated with a greater age and sex-adjusted hazard of 30-day readmission for MI (adjusted HR [aHR] 1.48 [95% CI 1.42-1.54] vs. asthma; aHR 1.36 [95% CI 1.31-1.41] vs. cellulitis) and VTE (aHR 1.28 [95% CI 1.24-1.33] vs. asthma; aHR 1.26, [95% CI 1.22-1.30] vs. cellulitis). Risks of MI and VTE attenuated over time. In a crossover-cohort analysis, the odds of MI (OR 1.68 [95% CI 1.62-1.73]) and VTE (OR 3.30 [95% 3.19-3.41]) were higher in the 30 days following discharge after respiratory infection than during the 30-day baseline period. Hospitalization for respiratory infection was associated with increased risks of thrombosis that were highest in the first 30-days after discharge and declined over time.

Coronavirus disease 2019 (COVID-19) is associated with increased rates of deep vein thrombosis (DVT) and pulmonary embolism (PE). Pulmonary Embolism Response Teams (PERT) have previously been associated with improved outcomes. We aimed to investigate whether PERT utilization, recommendations, and outcomes for patients diagnosed with acute PE changed during the COVID-19 pandemic. This is a retrospective cohort study of all adult patients with acute PE who received care at an academic hospital system in New York City between March 1st and April 30th, 2020. These patients were compared against historic controls between March 1st and April 30th, 2019. PE severity, PERT utilization, initial management, PERT recommendations, and outcomes were compared. There were more cases of PE during the pandemic (82 vs. 59), but less PERT activations (26.8% vs. 64.4%, p < 0.001) despite similar markers of PE severity. PERT recommendations were similar before and during the pandemic; anticoagulation was most recommended (89.5% vs. 86.4%, p = 0.70). During the pandemic, those with PERT activations were more likely to be female (63.6% vs. 31.7%, p = 0.01), have a history of DVT/PE (22.7% vs. 1.7%, p = 0.01), and to be SARS-CoV-2 PCR negative (68.2% vs. 38.3% p = 0.02). PERT activation during the pandemic is associated with decreased length of stay (7.7 ± 7.7 vs. 13.2 ± 12.7 days, p = 0.02). PERT utilization decreased during the COVID-19 pandemic and its activation was associated with different biases. PERT recommendations and outcomes were similar before and during the pandemic, and led to decreased length of stay during the pandemic.

Introduction and Objectives: Adjunctive false lumen embolization (FLE) with thoracic endovascular aortic repair (TEVAR) in patients with chronic aortic dissection is thought to induce FL thrombosis and favorable aortic remodeling. However, evidence is limited and the potential benefit of FLE remains unproven.
Method(s): Patients 18+ who underwent TEVAR for chronic aortic dissection with known FLE status in the SVS VQI database 1/2010-2/2020 were included. Ruptured patients and emergent procedures were excluded. Primary outcomes were in-hospital post-operative complications and all-cause mortality. Secondary outcomes included follow-up maximum aortic diameter change, re-intervention rates, and mortality.
Result(s): 884 patients were included: 46 had TEVAR/FLE and 838 had TEVAR alone. There was no significant difference between groups in terms of age, gender, comorbidities, maximum pre-operative aortic diameter, presentation symptomatology, or intervention indication. FLE was associated with significantly longer procedural times (178min vs. 146min, p=0.0002), increased contrast use (134mL vs. 113mL, p=0.02), and prolonged fluoroscopy time (34min vs. 21min, p<0.0001), but not associated with a significant difference in post-operative complications (17.4% vs. 13.8%, p=0.51), length of stay (6.5 vs. 5.7 days, p=0.18), or in-hospital all-cause mortality (0% vs. 1.3%, p=1). In mid-term follow-up (median 15.5months), all-cause mortality trended lower, but was not significant (2.2% vs. 7.8%); Kaplan-Meier analysis demonstrated no difference in overall survival between groups (p=0.23). Post-operative complications had the strongest independent association with all-cause mortality (HR 2.65, 95% CI 1.56-4.5, p<0.001). In patients with available follow-up imaging and re-intervention status, mean aortic diameter change (n=337, -0.71cm vs. -0.69cm, p=0.64) and re-intervention rates (n=487, 10% vs. 11.4%, p=1) were similar.
Conclusion(s): Adjunctive FLE can be performed safely in chronic thoracic aortic dissections without significantly higher perioperative morbidity or mortality. However, given lack of reduction in re-intervention rates, induction of significant favorable aortic remodeling, or definitive survival benefit compared to TEVAR alone, FLE utility remains unclear.
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Objective: Venous thromboembolism (VTE), including deep venous thrombosis (DVT) and pulmonary embolism (PE), affects approximately 5% of the population, and approximately 30% of affected individuals will die within 30 days of diagnosis. Given the prevalence of VTE and its associated mortality, our study evaluated the success of longitudinal treatment in patients diagnosed with VTE with particular attention to those lost to appropriate follow-up.
Method(s): This is a single-center retrospective study of all consecutive admitted (inpatient [IP]) and emergency department (ED) patients diagnosed with acute VTE by venous duplex ultrasound examination or chest computed tomography from January 2018 to March 2019. Patients with chronic DVT and those diagnosed in the outpatient setting were excluded. Data collected included age, sex, clinical setting at time of diagnosis, discharge anticoagulation choice, discharge disposition, and clinical follow-up. Lost to VTE follow-up (LTFU) was defined as those patients who did not follow up with vascular, cardiovascular, hematology/oncology, pulmonology, or primary care clinic for VTE management at our institution within 3 months after discharge. Patients discharged to hospice were excluded from LTFU analysis. Statistical analysis was performed using Stata 16 software (StataCorp LLC, College Station, Tex) and a threshold P value of <.05 set for significance.
Result(s): During the study period, 291 DVTs (237 lower extremity DVTs, 58 upper extremity DVTs, 4 mixed), 25 isolated PEs, and 55 PEs with associated DVT (53 lower extremity DVTs, 2 upper extremity DVTs) were identified in 371 patients. Of these patients, 130 (35%) were diagnosed in the ED and 241 (65%) in the IP setting. At discharge, 291 (78.4%) were receiving anticoagulation, 64 (17.3%) were not, and 16 (4.3%) were deceased. Ultimately, 133 patients (35.9%) were LTFU, 85% of whom were discharged on anticoagulation. There was no statistically significant difference between those LTFU with respect to age (P =.373), sex (P =.194), diagnosis time of day (P =.272), VTE type (P =.367), or discharge unit location (IP vs ED, 33.7% vs 43.8% LTFU; P =.114); however, there was a statistically significant association between longer IP length of stay and those patients LTFU in controlling for age (11.8 days vs 16.6 days; P =.028).
Conclusion(s): This study demonstrates that more than one-third of patients diagnosed with VTE at our institution are LTFU, suggesting that significant improvement could be achieved by establishing a pathway for the targeted transition of care to a VTE-specific follow-up clinic.
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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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Objective: Aortic neck dilation (AND) can occur in nearly 25% of patients after EVAR, resulting in loss of proximal seal and aortic rupture. Fenestrated endovascular aneurysm repair (FEVAR) affords increased treatment options for patients with shorter infrarenal aortic necks; however, AND has not been well characterized in these patients. This study sought to compare AND in patients undergoing FEVAR vs standard endovascular aneurysm repair (EVAR).
Method(s): Retrospective review was conducted of prospectively collected data of 20 consecutive FEVAR patients (Cook Zenith fenestrated; Cook Medical, Bloomington, Ind) and 20 EVAR patients (Cook Zenith). Demographic and anatomic characteristics, procedural details, and clinical outcome were analyzed. Preoperative, 1-month postoperative, and longest follow-up computed tomography scans were analyzed using a dedicated three-dimensional workstation. Abdominal aortic aneurysm (AAA) neck diameter was measured in 5-mm increments from the lowest renal artery. Standard statistical analysis was performed.
Result(s): Demographic characteristics did not differ significantly between the two cohorts. The FEVAR group had larger mean aortic diameter at the lowest renal artery, shorter infrarenal aortic neck length, increased prevalence of nonparallel neck shape, and longer AAA length (Table). On follow-up imaging, the suprarenal aortic segment dilated significantly more at all suprarenal locations in the FEVAR cohort, whereas the infrarenal aortic neck segment dilated significantly less compared with the EVAR group (Table). The FEVAR group demonstrated significantly greater sac regression vs the EVAR group. Positive aortic remodeling, as evidenced by increased distance from the celiac axis to the most cephalad margin of the AAA, occurred to a more significant degree in the FEVAR cohort. Device migration, endoleak occurrence, and need for reintervention were similar in both groups.
Conclusion(s): Compared with EVAR, patients undergoing FEVAR had greater extent of suprarenal AND, consistent with a more diseased native proximal aorta. However, the infrarenal neck, which is shorter and also more diseased in FEVAR patients, appears more stable in the postoperative period compared with EVAR cases. Moreover, the FEVAR cohort had significantly greater sac shrinkage and improved aortic remodeling. The suprarenal seal zone in FEVAR may confer a previously undescribed increased level of protection against infrarenal neck dilation and lessen endotension, resulting in more rapid and dramatic sac shrinkage and contributing to a more durable aortic repair. [Formula presented]
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