Faculty Bibliography

OBJECTIVES/OBJECTIVE:Patients with prior infrarenal aortic intervention represent an increasing demographic of patients undergoing thoracic endovascular aortic repair (TEVAR) and/or complex EVAR. Studies have suggested that prior abdominal aortic surgery is a risk factor for spinal cord ischemia (SCI). However, these results are largely based on single-center experiences with limited multi-institutional and national data assessing clinical outcomes in these patients. The objective of this study was to evaluate the effect of prior infrarenal aortic surgery on SCI. METHODS:The Society for Vascular Surgery Vascular Quality Initiative database was retrospectively reviewed to identify all patients ≥18 years old undergoing TEVAR/complex EVAR from January 2012 to June 2020. Patients with previous thoracic or suprarenal aortic repairs were excluded. Baseline and procedural characteristics and postoperative outcomes were compared by group: TEVAR/complex EVAR with or without previous infrarenal aortic repair. The primary outcome was postoperative SCI. Secondary outcomes included postoperative hospital length of stay (LOS), bowel ischemia, renal ischemia, and 30-day mortality. Multivariate regression was used to determine independent predictors of postoperative SCI. Additional analysis was performed for patients undergoing isolated TEVAR. RESULTS:A total of 9506 patients met the inclusion criteria: 8691 (91.4%) had no history of infrarenal aortic repair and 815 (8.6%) had previous infrarenal aortic repair. Patients with previous infrarenal repair were older with an increased prevalence of chronic kidney disease (p=0.001) and cardiovascular risk factors including hypertension, chronic obstructive pulmonary disease, and smoking history (p<0.001). These patients presented with larger maximal aortic diameters (6.06±1.47 cm versus 5.15±1.76 cm; p<0.001) and required more stent grafts (p<0.001) with increased intraoperative blood transfusion requirements (p<0.001), and longer procedure times (p<0.001). Univariate analysis demonstrated no difference in postoperative SCI, postoperative hospital LOS, bowel ischemia, or renal ischemia between the two groups. Thirty-day mortality was significantly higher in patients with prior infrarenal repair (p=0.001). On multivariate regression, prior infrarenal aortic repair was not a predictor of postoperative SCI, while aortic dissection (odds ratio [OR] 1.65; 95% confidence interval [CI] 1.26-2.16, p<0.001), number of stent grafts deployed (OR 1.45; 95% CI 1.30-1.62, p<0.001), and units of packed red blood cells transfused intraoperatively (OR 1.33; 95% CI 1.03-1.73, p=0.032) were independent predictors of SCI. CONCLUSIONS:Although TEVAR/complex EVAR patients with prior infrarenal aortic repair constituted a sicker cohort with higher 30-day mortality, the rate of SCI was comparable to patients without prior repair. Previous infrarenal repair was not associated with risk of SCI.

BACKGROUND:For women with left common iliac vein compression (ie, May-Thurner syndrome) who undergo venous stenting and subsequently become pregnant, concerns have been raised regarding a possible compromise of stent patency due to compression from the gravid uterus and the hypercoagulability induced by pregnancy. Only a small body of literature exists on this subject, and limited management guidelines are available. The present study was designed to evaluate the safety of iliac vein stenting for May-Thurner syndrome (MTS) with subsequent pregnancy. METHODS:Female patients who had undergone common iliac vein stenting at our center who were aged 18 to 45 years and had subsequently become pregnant were identified. A retrospective medical record review of eight eligible patients was conducted, recording the demographics, procedural characteristics, and anticoagulation strategies. The primary outcome evaluated was stent patency. RESULTS:All eight patients had undergone left common iliac vein stenting for MTS. A total of eight stents were placed, and all demonstrated duplex ultrasound patency throughout pregnancy and postpartum. Seven patients delivered healthy pregnancies, and one experienced a stillbirth. The clinical CEAP (clinical, etiologic, anatomic, pathophysiologic) class remained unchanged or improved from pregnancy to postpartum for all patients. The average age at stent placement was 31 ± 5 years, and the average interval from stent placement to pregnancy was 28 ± 19 months. One patient developed nonobstructive deep vein thrombosis (DVT) of the left femoral vein during pregnancy and was treated with therapeutic enoxaparin. The nonobstructive DVT did not compromise the iliac vein stent. Two patients received low-dose aspirin and prophylactic doses of enoxaparin, one for a history of DVT and factor V Leiden and one for a recent history of fertility treatment. The five remaining patients received no anticoagulation, three received low-dose aspirin, and two received no antiplatelet therapy. CONCLUSIONS:Common iliac vein stent patency was not compromised by subsequent pregnancy in our eight patients with MTS. Furthermore, the stents remained patent throughout pregnancy in patients receiving a wide range of anticoagulation and antiplatelet treatments, suggesting that no uniform therapeutic threshold exists and treatment should be individualized. For most patients, low-dose aspirin alone or no treatment was adequate. This could have implications for counseling women who require intervention for MTS and are of child-bearing age.

INTRODUCTION/BACKGROUND:The treatment of a refluxing perforator is indicated in the setting of severe chronic venous insufficiency, but there are limited data on the presence of multilevel disease in these patients. This study sought to evaluate whether the presence of a pathologic perforator is predictive of the presence of central venous pathology. METHODS:This study was a retrospective review of the institutional vascular quality initiative (VQI) database. Consecutive patient-limbs were identified who underwent intervention of refluxing perforators. The patients who underwent imaging, including MRI or CT (Group A) were compared to those who did not undergo imaging (Group B). The treated limbs in Group A were also compared to the contralateral limbs as an internal control. Anatomical findings on imaging were analyzed by two independent investigators. The primary outcome was the presence and degree of central venous stenosis as measured by an orthogonal diameter reduction of > 50% by axial imaging. Secondary outcomes included demographic and clinical differences between the two groups, frequency of central venous intervention, and duration of ulcer healing. Standard statistical analysis was performed. RESULTS:Ninety-three patient-limbs underwent treatment of a pathologic perforator, with 30 in Group A and 63 in Group B. The following demographic and clinical variables were higher in Group A compared to Group B: Male gender, BMI, deep venous thrombosis history, recent or active anticoagulation use, perforator diameter, Clinical Etiology Anatomy Pathophysiology class 4, 5 or 6, and Venous Clinical Severity Score. Radiographic analysis of Group A revealed concordance of a treated pathological perforator with an ipsilateral central venous stenosis in 53.3% of patients, and a higher frequency of common iliac vein stenosis (50% vs 21.4%, P = 0.024) and external iliac vein stenosis (20% vs 0%, P = 0.012) compared to the contralateral limbs. When separated by left or right limb, the left limbs exhibited a greater degree of common iliac vein stenosis as compared to the contralateral limbs (50.7±20.9% vs 16.3±16.5%, P < 0.001) as well as a greater frequency of >50% common iliac vein stenosis (46.7% vs 13.3%, P = 0.046). The right limbs exhibited a greater frequency of > 50% external iliac vein stenosis as compared to contralateral limbs (33.3% vs 0%, P = 0.022). CONCLUSIONS:This study suggests that patients with severe chronic venous insufficiency who undergo treatment for a pathologic perforator may have additional ipsilateral central venous pathology, supporting the presence of multilevel disease. Additional axial imaging might unmask central venous pathology and provide another option for treatment.

BACKGROUND:Histological analyses of deep vein thrombi (DVT) are based on autopsy samples and animal models. No prior study has reported on thrombus composition following percutaneous mechanical extraction. As elements of chronicity and organization render thrombus resistant to anticoagulation and thrombolysis, a better understanding of clot evolution may inform therapies. METHODS:We performed histologic evaluation of DVTs from consecutive patients undergoing mechanical thrombectomy for extensive iliofemoral DVTs using the Clottriever/ Flowtriever device (Inari Medical, Irvine, CA). Thrombi were scored in a semi-quantitative manner based on the degree of fibrosis (collagen deposition on trichrome stain), and organization (endothelial growth with capillaries and fibroblastic penetration). RESULTS:Twenty-three specimens were available for analysis with 20 presenting with acute DVT (≤14 days from symptom onset). Eleven of 23 patients (48%) had >5% fibrosis (collagen deposition) and 14/23 patients (61%) had >5% organization (endothelial growth, capillaries, fibroblasts). Four patients with acute DVT had ≥25% organized thrombus and 2 had ≥ 25% collagen deposition. Among the 20 patients with acute DVT, 40% had >5% fibrosis and 55% had > 5% organization. Acuity of DVT did not correlate with the fibrosis or organizing scores. CONCLUSIONS:A large proportion of patients with acute DVT have histologic elements of chronicity and fibrosis. A better understanding of the relationship between such elements and response to anticoagulants and fibrinolytics may inform our approach to therapeutics.

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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Objective: Autogenous great saphenous vein (GSV) is considered the conduit of choice for lower extremity bypass (LEB). However, the optimal configuration has remained a source of debate. We compared the outcomes of patients who had undergone LEB using in situ and reversed configuration.
Method(s): The Vascular Quality Initiative database (January 2003 to February 2021) was queried for patients undergoing LEB with in situ and reversed GSV. Patient demographics, procedural detail, and in-hospital and follow-up outcomes were collected. The primary endpoint was primary patency. The second endpoints included freedom from major adverse limb events (MALE; defined as major lower extremity amputation and reintervention), limb salvage, and freedom from reintervention at 1 year. Multivariable models were created to determine the association between bypass configuration and outcomes of interest.
Result(s): Of the 8234 patients who had undergone LEB, in situ and reversed GSV was used in 3546 and 4688 patients, respectively. Patients with in situ bypass were older with higher rates of cardiopulmonary and renal comorbidities. The patients who had undergone reversed bypass were more likely to have undergone previous LEBs and endovascular interventions. The indication for LEB was similar between the in situ and reversed bypass cohorts. In situ bypass had been performed more frequently from the common femoral artery and to more distal targets (tibial or peroneal). Reversed bypass was associated with higher intraoperative blood loss and a longer operative time. Perioperatively, in situ bypass had resulted in greater rates of reintervention (13.2% vs 11.1%; P =.004) and surgical site infection (4.2% vs 3%; P =.003) and lower primary patency (93.5% vs 95%; P =.004). At 1 year, in situ bypass had a lower rate of MALE (22.6% vs 25.6), mainly driven by a lower rate of reintervention (19.4% vs 21.6%). The primary patency and limb salvage rates were not different. On multivariable analysis, in situ bypass was associated with lower primary patency loss (hazard ratio [HR], 0.9; 95% confidence interval [CI], 0.82-0.98), reintervention (HR, 0.88; 95% CI, 0.8-0.97), and MALE (HR, 0.89; 95% CI, 0.81-0.97) but did not affect the rate of limb salvage compared with reversed bypass.
Conclusion(s): Compared with those with reversed GSV, LEBs with in situ GSV confer improved primary patency and MALE at midterm. Our results have demonstrated that an in situ configuration might be a favorable option for appropriately selected patients with suitable anatomy.
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Objective: Type II endoleaks (T2E), commonly identified after EVAR, are associated with late endograft failure and secondary rupture. Quantity and size of aortic aneurysm sac outflow vessels (AASOV), namely the inferior mesenteric, lumbar, and accessory renal arteries, have been implicated as known risk factors for persistent T2E. Given technical difficulties associated with post-EVAR embolization, prophylactic coil embolization of AASOV-related T2E has been advocated to prevent retrograde T2E; however, current evidence is limited. We sought to examine the effect of concomitant prophylactic AASOV coil embolization in patients undergoing EVAR.
Method(s): Patients 18 and older in the Society for Vascular Surgery Vascular Quality Initiative database who underwent elective EVAR for intact aneurysms between January 2009 and November 2020 were included. Patients with a history of prior aortic repair and those without available follow-up data were excluded. Patient demographics, operative characteristics, and outcomes were analyzed by group: EVAR with or without prophylactic AASOV embolization (emboEVAR). Primary outcomes of interest were rates of in-hospital postoperative complications, incidence of aneurysmal sac regression (>=5 mm), and rates of reintervention in follow-up.
Result(s): A total of 15,060 patients were included: 272 had emboEVAR and 14,788 had EVAR alone. There was no significant difference between groups in terms of age, comorbidities, or anatomic characteristics including mean maximum preoperative aortic diameter (5.5 vs 5.6 cm, P =.48) (Table I). emboEVAR was associated with significantly longer procedural times (148 vs 124 minutes, P <.0001), prolonged fluoroscopy (32 vs 23 minutes, P <.0001), increased contrast use (105 vs 91 mL, P <.0001), without significant reduction in T2E at completion (17.7% vs 16.3%, P =.54). Incidences of postoperative complications (3.7% vs 4.6%, P =.56), index hospitalization reintervention rates (0.7% vs 1.3%, P =.59), length of stay (1.8 vs 2 days, P =.75), and 30-day mortality (0% vs 0%, P = 1) were similar between groups. In mid-term follow-up (14.6 +/- 6.2 months), the emboEVAR group had a significant mean reduction in maximum aortic diameter (0.69 vs 0.54 cm, P =.006) with a higher proportion experiencing sac regression >=5 mm (53.5% vs 48.7%) and reintervention rates were similar between groups. On multivariate analysis, prophylactic AASOV (odds ratio: 1.34, confidence interval: 1.04-1.74, P =.024) was a significant independent predictor of sac regression (Table II).
Conclusion(s): Prophylactic AASOV embolization can be performed safely for patients with intact aortic aneurysms undergoing elective EVAR without significant associated perioperative morbidity or mortality. emboEVAR is associated with significant sac regression compared with EVAR alone in mid-term follow-up. This technique shows promise and future efforts should focus on elucidating the role of concomitant selective vs complete prophylactic AASOV embolization in patients undergoing EVAR. [Formula presented] [Formula presented]
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Objectives: In patients with carotid stenosis, both the severity of the stenosis as well as the plaque morphology influence the likelihood of future transient ischemic attack or stroke. In general, severely stenotic lesions are presumed to have a higher embolic potential than moderately stenotic lesions. Carotid intervention is indicated in patients with both moderate and severe stenosis with related cerebrovascular symptoms. However, the effect of the degree of carotid stenosis in symptomatic patients upon the outcome of carotid intervention has not been extensively studied.
Method(s): The Society for Vascular Surgery Quality Initiative database was queried for all patients undergoing transfemoral carotid stenting (CAS), carotid endarterectomy (CEA), and transcervical carotid stenting (TCAR) between 2003 and 2020. Patients undergoing interventions for symptomatic disease were included in the analysis. Patients were stratified into two cohorts based on the severity of stenosis-moderate (0%-69%) and severe (greater than or equal to 70%). Primary endpoints were perioperative neurologic events (strokes and transient ischemic attacks [TIAs]). Secondary endpoints were perioperative mortality and postoperative complications.
Result(s): Over 50,000 patients were included in the analysis: 5296 patients (8.9%) underwent TCAR, 7844 (13.3%) underwent CAS, and 45,853 (77.8%) underwent CEA for symptomatic carotid artery disease. In the TCAR and CEA cohorts, patients with moderate stenosis had a significantly higher rate of perioperative neurologic events than patients with severe stenosis (TCAR 4.3% vs 3.0%; P =.033; CEA 3.0% vs 2.3%; P <.001). In contrast, in patients undergoing CAS, there was no significant difference noted in the perioperative neurologic event rate (3.5% in moderate stenosis group vs 3.8% in severe stenosis group; P =.518). There were no differences in perioperative myocardial infarction or mortality (Table). On multivariable analysis, moderate stenosis was significantly and independently associated with an increased rate of neurologic events in the TCAR (odds ratio [OR], 0.833; 95% confidence interval, 0.693-1.000; P =.05), and CEA (odds ratio, 0.901; 95% confidence interval, 0.861-0.944; P <.001) cohorts.
Conclusion(s): Moderate carotid stenosis was associated with increased perioperative neurologic events in patients undergoing TCAR and CEA, but not CAS. Therefore, this effect was noted only in the cohorts that require direct open surgical manipulation of the cervical carotid artery (TCAR and CEA). Moderately stenotic lesions that become symptomatic likely have worse intrinsic plaque morphology than severely stenotic lesions, producing cerebrovascular symptoms at a lower degree of stenosis. The mechanism of such events warrants further evaluation with a particular focus on plaque morphology and brain physiology. [Formula presented]
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Objective: Statins are often used for primary and secondary prevention of cardiovascular events. Multiple studies have demonstrated a significant reduction in perioperative complications after carotid endarterectomy for patients taking statins. However, data for statin use for patients undergoing transcarotid artery revascularization (TCAR) are limited. We evaluated the effects of statin use on the postoperative outcomes after TCAR.
Method(s): The records of the Vascular Quality Initiative carotid artery stenting registry (2012-2020) were reviewed for patients who had undergone TCAR. The patient demographics, perioperative characteristics, and 30-day outcomes were compared between the patients treated with and without statins (statin and no-statin group, respectively). Multivariable logistic regression models were used to estimate the effect of statins on the postoperative outcomes.
Result(s): A total of 15,797 patients had undergone TCAR, of whom, 10,116 (64%) were men. Of the 15,797 patients, 14,152 (89.6%) were taking a statin preoperatively (Table I). The statin group was more likely to have hypertension (91% vs 87%; P <.001), coronary artery disease (26% vs 23%; P =.008), and diabetes mellitus (33% vs 29%; P <.001). The incidence of both prior ipsilateral stroke (17.2% vs 13.5%; P <.001) and recent ipsilateral stroke (<=30 days; 7.1% vs 5.6%; P =.02) was higher in the statin group. No differences were found in the perioperative characteristics, including median operative time, contrast amount used, technical success, and number of stents used. Perioperative stroke and major adverse cardiac events (MACE; myocardial infarction, congestive heart failure, dysrhythmia) occurred in 1.5% and 2.4% of the statin group and 1.4% and 2.3% of the no-statin group, respectively. Controlling for covariates with the logistic regression method, statin use was associated with a 62% reduction in the odds of mortality (odds ratio, 0.38; 95% confidence interval, 0.19-0.99; P =.047; Table II) for patients who had experienced a perioperative stroke or MACE after TCAR.
Conclusion(s): Statin use was associated with a significant reduction in postoperative mortality for patients who had experienced a stroke or MACE after TCAR. Therefore, strict adherence to statin use is strongly recommended, especially for patients who could be at high risk of major postoperative complications. [Formula presented] [Formula presented]
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Objective: Data regarding the effect of bilateral internal iliac artery (IIA) occlusion during endovascular abdominal aortic aneurysm repair (EVAR) are conflicting, with reported varied risks of pelvic and gastrointestinal ischemia. The aim of our study was to report the perioperative and long-term outcomes of IIA occlusion with origin graft coverage in patients undergoing elective EVAR.
Method(s): Using the Vascular Quality Initiative database (2010-2020), we retrospectively identified patients who had undergone EVAR for infrarenal abdominal aortic aneurysms and aortoiliac aneurysms with or without IIA occlusion by graft coverage or coils. The patients were stratified into three groups according to IIA occlusion status (none, unilateral, bilateral). The baseline characteristics, procedural details, in-hospital outcomes, and overall survival at 5 years were reviewed. The primary outcomes were in-hospital mortality and complications. The secondary outcomes included 5-year mortality. Cox proportional hazards models were used to determine the predictive factors of perioperative and 2-year mortality.
Result(s): A total of 26,690 patients were identified (mean age, 73.5 years; 82% male) who had undergone elective EVAR with bifurcated endografts. Of the 26,690 patients, 2195 (8.2%) had undergone adjunctive unilateral IIA origin graft occlusion, 523 (2%) had undergone bilateral IIA origin graft occlusion, and 23,970 (89.8%) had not undergone any IIA graft occlusion. Perioperatively, no statistically significant differences were found in the incidence of death (0.4% vs 0.6% vs 0.4%; P =.2), gastrointestinal ischemia (0.1% vs 0.1% vs 0.2%; P =.888), unplanned reoperation (1.5% vs 1.8% vs 2.3%; P =.181), or cardiopulmonary complications (2.5% vs 2.8% vs 3.4%; P =.247) among those with no, unilateral, and bilateral IIA origin graft occlusion, respectively (Table). The Kaplan-Meier estimate demonstrated comparable overall survival at 5 years (none, 86.7%; unilateral, 85.2%; bilateral, 89.4%; P =.133; Fig). On multivariable analysis, the status of IIA origin graft coverage was not associated with increased perioperative mortality or complications.
Conclusion(s): EVAR with bilateral IIA interruption was associated with favorable perioperative outcomes with a low rate of major complications. At the time of EVAR, unilateral and bilateral IIA occlusion with a stent-graft did not appear to confer additional risks of perioperative complications and mortality. Our results showed the safety of bilateral IIA interruption in patients undergoing elective EVAR for abdominal aortic aneurysms and aortoiliac aneurysms. [Formula presented] [Formula presented]
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