Faculty Bibliography

OBJECTIVE:In 2014, in addition to male smokers aged 65-75 years, the U.S. Preventive Services Task Force (USPSTF) recommended abdominal aortic aneurysm (AAA) screening for male never-smokers aged 65-75 years with cardiovascular risk factors (Grade C). The USPSTF evolved from a negative to neutral position on screening for female smokers aged 65-75 years (Grade I). We sought to determine whether 2014 guidelines resulted in more AAA repairs in these populations. METHODS:We queried the Vascular Quality Initiative national database (2013-2018) for elective endovascular aortic repairs and open aortic repairs. We implemented difference-in-differences (DID) analysis, a causal inference technique that adjusts for secular time trends, to isolate changes in repair numbers due to the 2014 USPSTF guidelines. Our DID models compared changes in repair numbers in patient groups targeted by the USPSTF updates (intervention group) to those in unaffected, older patient groups (control), before and after 2014. The first model compared changes in repair numbers between male never-smokers aged 65-75 years (intervention group) and 76-85 years (control). The second model compared repair numbers between female smokers aged 65-75 years (intervention group) and 76-85 years (control). RESULTS:There was no significant change in male never-smokers (n = 1,295) aged 65-75 (42%) vs. 76-85 (58%) undergoing AAA repairs after guideline updates, averaged over 4.5 years (+2.4 percentage points; 95% Confidence Interval [CI] -.56-5.26). However, when their primary insurer was Medicare, male never-smokers aged 65-75 years compared with 76-85 years underwent significantly more repairs over 4.5 years (+3.69 percentage points; 95% CI.16-7.22; representing a 10.4% relative increase from baseline in the proportion of male never-smokers on Medicare undergoing AAA repair). Comparing female smokers (n = 2,312) aged 65-75 (54%) vs. 76-85 (46%), there was no significant change in repairs over 4.5 years (-.66 percentage points; 95% CI -4.57-3.26). CONCLUSIONS:The USPSTF 2014 AAA guidelines were associated with modestly increased repairs in male never-smokers aged 65-75 years only on Medicare. There was no impact among female smokers. Higher-grade recommendations and improved guideline adherence may be requisites for change.

OBJECTIVE:Restenosis after carotid endarterectomy (CEA) poses unique therapeutic challenges, with no specific guidelines available on the operative approach. Traditionally, transfemoral carotid artery stenting (TfCAS) has been regarded as the preferred approach to treating restenosis after CEA. Recently, transcarotid artery revascularization with a flow-reversal neuroprotection system (TCAR) has gained popularity as an effective alternative treatment modality for de novo carotid artery stenosis. The aim of the present study was to compare the contemporary perioperative outcomes of TfCAS and TCAR in patients with prior ipsilateral CEA. METHODS:The Vascular Quality Initiative database was reviewed for patients who had undergone TfCAS and TCAR for restenosis after prior ipsilateral CEA between January 2016 and August 2020. The primary outcome was the 30-day composite outcome of stroke and death. The secondary outcomes included 30-day stroke, transient ischemic attack (TIA), myocardial infarction (MI), death, and composite 30-day outcomes of stroke, death, and TIA, stroke and TIA, and stroke, death, and MI. Multivariable logistic regression models were used to evaluate the outcomes of interest after adjustment for potential confounders and baseline differences between cohorts. RESULTS:Of 3508 patients, 1834 and 1674 had undergone TfCAS and TCAR, respectively. The TCAR cohort was older (mean age, 71.6 years vs 70.2 years; P < .001) and less likely to be symptomatic (27% vs 46%; P < .001), with a greater proportion taking aspirin (92% vs 88%; P = .001), a P2Y12 inhibitor (89% vs 80%; P < .001), and a statin (91% vs 87%; P = .002) compared with the TfCAS cohort. Perioperatively, the TCAR cohort had had lower 30-day composite outcomes of stroke/death (1.6% vs 2.7%; P = .025), stroke/death/TIA (1.8% vs 3.3%; P = .004), and stroke/death/MI (2.1% vs 3.2%; P = .048), primarily driven by lower rates of stroke (1.3% vs 2.3%; P = .031) and TIA (0.2% vs 0.7%; P = .031). Among asymptomatic patients, the incidence of stroke (0.6% vs 1.4%; P = .042) and the composite of stroke/TIA (0.8% vs 1.8%; P = .036) was significantly lower after TCAR than TfCAS, and TCAR was associated with a lower incidence of TIA (0% vs 1%; P = .038) among symptomatic patients. On adjusted analysis, the TCAR cohort had lower odds of TIA (adjusted odds ratio, 0.17; 95% confidence interval, 0.04-0.74; P = .019). CONCLUSIONS:Among patients undergoing carotid revascularization for restenosis after prior ipsilateral CEA, TCAR was associated with decreased odds of 30-day TIA compared with TfCAS. However, the two treatment approaches were similarly safe in terms of the remaining perioperative outcomes, including stroke and death and stroke, death, and MI. Our results support the safety and efficacy of TCAR in this subset of patients deemed at high risk of reintervention.

BACKGROUND:The effect of anticoagulation therapy (AC) on hemodialysis access patency and related complications is not well defined. Patients on long-term or chronic AC due to their underlying comorbid conditions may be particularly susceptible to access-related bleeding and complications from repetitive cannulation. Our goal is to assess the effect of anticoagulation therapy on outcomes after access creation. METHODS:The Vascular Quality Initiative (VQI) database was queried for patients undergoing arteriovenous fistula (AVF) or graft (AVG) placement, from 2011 to 2019. Only patients with data on post-procedural AC status were included. Anticoagulation use was defined as patients on warfarin, dabigatran, or rivaroxaban after access creation at postoperative follow up. Demographic and procedural details were analyzed. Wound infection and patency rates at six months were assessed. Binomial logistic regression analysis was performed to assess the association of anticoagulation use with these outcomes. RESULTS:A total of 27,757 patients underwent access creation, with the majority undergoing AVF creation (78.8%). The average age was 61.4 years and 55.3% were male. 12.9% of patients were on postoperative AC. The wound infection rate was 2.3- 3.8% in the no AC and AC cohorts, respectively (P < 0.001). At six months follow-up, patency was 85.7- 84.3% in the no AC and AC cohorts, respectively (P = 0.044). Expectedly, grafts had lower patency rates compared to AVF; those within the no AC cohort had a patency of 83.0% compared to 81.2 % in those on AC (P = 0.106). On multivariable analysis, anticoagulation use was associated with a higher risk of wound infections (odds ratio [OR] 1.513, 95% confidence interval [CI] 1.160-1.973, P = 0.002). AC use did not significantly affect access patency. CONCLUSION/CONCLUSIONS:Anticoagulation therapy was associated with a higher rate of wound infections but did not affect short-term access patency within six-months. These patients warrant close surveillance of their access for signs of infection. Furthermore, long-term implications of anticoagulation needs further evaluation.

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.

OBJECTIVES/OBJECTIVE:In patients deemed high risk for carotid endarterectomy (CEA) who are indicated for treatment of carotid artery stenosis (CAS), transcarotid artery revascularization (TCAR) has been demonstrated as a safe and effective alternative to trans-femoral carotid artery stenting (TF-CAS). Compared to CEA, where approx. 12% of patients undergoing awake intervention do not tolerate internal carotid artery (ICA) clamping, only 1-2% of patients were observed to have intolerance to flow reversal during TCAR based on data from the ROADSTER1/2 trials. This study reviewed awake interventions from those trials to assess factors associated with intolerance to flow reversal and review how those cases were managed. METHODS:This is a retrospective review of prospectively collected data from Reverse Flow Used During Carotid Artery Stenting Procedure (ROADSTER) multicenter trial along with the subsequent post-approval (ROADSTER-2) trial. The subset of patients from both trials undergoing awake TCAR was analyzed to compare demographics, procedural details, and anatomic factors between patients who did and did not experience intolerance to reversal of flow to assess for predisposing factors. Patients were deemed intolerant to flow reversal at the discretion of the operator, often related to changes in completion of neurologic tasks, hemodynamic stability, or patient reported symptoms. RESULTS:103 patients from ROADSTER and 194 patients from ROADSTER-2 underwent TCAR under local/regional anesthesia. Of these, 8 patients had intolerance to flow reversal, though all cases were successfully completed. While intra-operative hemodynamic data was only available for 5 of the 8 intolerant patients, none experienced hypotension. 4 cases were completed under low flow reversal, 3 cases were successfully weaned from low to high flow over several minutes, and 1 case required general anesthesia. No significant association was found between intolerance to flow reversal and comorbidities including diabetes mellitus (DM), hypertension (HTN), hyperlipidemia (HLD), congestive heart failure (CHF), prior MI or angina, pre-op CAS-related symptoms, prior stroke, prior CAS or CEA, prior neck radiation, tandem stenosis, high cervical stenosis, or hostile neck (tables 1, 2). A trend towards significance was seen with chronic obstructive pulmonary disease (COPD) and contralateral carotid artery occlusion (p= 0.086 and 0.139, respectively). CONCLUSIONS:Despite intolerance to flow reversal, TCAR cases were successfully completed by adjusting reversal-of-flow rate and do not typically require conversion to GETA. While factors contributing to intolerance of flow reversal during TCAR remain poorly understood, this study identified a trend towards significance with an association of pre-existing COPD and contralateral carotid artery occlusion. Given the low number of patients who experienced this issue, a larger sample size is required to better elucidate these trends.

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.

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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Objective: Although beta-blocker (BB) use is routine for type B aortic dissections (TBADs), its effect in patients undergoing thoracic endovascular aortic repair (TEVAR) is unclear. Furthermore, the effect of BB use on the perioperative outcomes after TEVAR has not been evaluated. We evaluated the effect of BB use on the perioperative outcomes in patients with TBAD undergoing TEVAR.
Method(s): The Society for Vascular Surgery Vascular Quality Initiative database was queried for all patients who had undergone TEVAR for TBAD between September 2012 and February 2020. BB use was defined as the use of such medications for >=30 days preoperatively. Patients were dichotomized according to preoperative BB use (no-BB and BB cohorts). The patient characteristics, procedural details, and postoperative outcomes were compared. The primary endpoints were 30-day mortality and overall postoperative complications, including myocardial infarction, new dysrhythmia, congestive heart failure, access site complications, respiratory, cerebrovascular symptoms, and arm, leg, renal, spinal cord, and gastrointestinal ischemia requiring surgical intervention.
Result(s): Of 2283 patients undergoing TEVAR for TBAD, 1130 (49%) were receiving a BB preoperatively. The BB cohort was older with greater proportions of hypertension, coronary artery disease, congestive heart failure, diabetes, chronic kidney disease, and end-stage renal disease (Table I). Additionally, the BB cohort were more likely to be taking aspirin, a P2Y12 antagonist, a statin, or an ACE inhibitor, and/or receiving anticoagulation therapy preoperatively. The non-BB cohort had more nonelective, symptomatic, and acute dissections. The procedural details, including rates of open conversion and general anesthesia, estimated blood loss, transfusion requirements, and operative times were comparable. On univariate analysis, the BB cohort had a lower risk of overall postoperative complications (22% vs 33%; P <.001) and mortality (4.7% vs 7.7%; P =.003) compared with the non-BB cohort. On multivariable analysis, BB use was associated with a 22% reduction in the odds of postoperative complications (odds ratio, 0.78; 95% confidence interval, 0.62-0.99; P =.044) but did not influence mortality (odds ratio, 1.14; 95% confidence interval, 0.73-1.71; P =.562; Table II).
Conclusion(s): BB use was associated with a significant reduction in postoperative complications for patients undergoing TEVAR for TBAD. Therefore, BB use should be strongly encouraged for appropriately selected patients undergoing TEVAR. [Formula presented] [Formula presented]
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Objective: There is a paucity of data evaluating outcomes of lower extremity bypass (LEB) using suprainguinal inflow for infrainguinal vessels. The purpose of this study is to report outcomes after LEB originating from aortoiliac arteries to infrafemoral targets.
Method(s): The Vascular Quality Initiative database (2003-2020) was queried for patients undergoing LEB originating from the aortoiliac arteries and to the popliteal and tibial arteries. Patients were stratified into three cohorts based on outflow targets (above-knee popliteal, below-knee popliteal and tibial arteries). Perioperative and 1-year outcomes including primary patency, amputation-free survival, and major adverse limb events (MALEs) were compared, and the Cox proportional hazards model was used to estimate the independent prognostic factors of outcomes.
Result(s): Of 403 LEBs, 389 (96.5%) originated from the external iliac artery, whereas the remaining from the aorta and common iliac artery. A total of 116 (28.8%), 151 (27.5%), and 136 (43.7%) were to the above-knee popliteal, below-knee popliteal, and tibial arteries, respectively (Table). In total, 194 (48%) and 186 (46%) patients had prior ipsilateral LEB and percutaneous vascular interventions, respectively. Below-knee popliteal and tibial bypasses were performed more frequently in patients with chronic limb-threatening ischemia (70% and 70% vs 48%; P <.001). Vein conduit was more often used for tibial bypass than for above- and below-knee popliteal bypasses (46% vs 22% and 17%; P <.001). In the perioperative period, below-knee popliteal and tibial bypass patients had higher reoperation rates (17% and 14% vs 5%; P =.015) and lower primary patency (91% and 90% vs 96%; P =.044) than above-knee bypass patients. Perioperative pulmonary complication and mortality rates were similar among the cohorts. At 1 year, compared with above-knee popliteal bypasses, below-knee and tibial bypasses demonstrated lower primary patency (60.9% and 62.3% vs 83.3%; P <.001; Fig) and amputation-free survival (69.1% and 66.4% vs 79.4%; P =.0223), but freedom from MALEs were similar (87.2% and 82.8% vs 90.9%; P =.0585). On multivariable analysis, compared with above-knee popliteal bypasses, tibial bypasses were independently associated with increased loss of primary patency (hazard ratio, 1.9; 95% confidence interval, 1.03-3.51; P =.039), but with similar major ipsilateral amputation/death and MALEs.
Conclusion(s): Compared with those using historic infrainguinal inflow, LEBs with suprainguinal inflow appear to have accepTable rates of 1-year patency and limb salvage in patients at high risk of bypass failure. Tibial outflow target was independently associated with worse primary patency. [Formula presented] [Formula presented]
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