Faculty Bibliography

OBJECTIVE:Contemporary commercially available endovascular devices for the treatment of abdominal aortic aneurysm (AAA) include standard endovascular aortic repair (sEVAR) or fenestrated EVAR (fEVAR) endografts. However, aortic neck dilatation (AND) can occur in nearly 25% of patients following EVAR, resulting in loss of proximal seal with risk of aortic rupture. AND has not been well characterized in fEVAR, and direct comparisons studying AND between fEVAR and sEVAR have not been performed. This study aims to analyze AND in the infrarenal and suprarenal aortic segments, including seal zone, and quantify sac regression following fEVAR implantation compared to sEVAR. METHOD/METHODS:A retrospective review of prospectively collected data on 20 consecutive fEVAR patients (Cook Zenith® Fenestrated) and 20 sEVAR (Cook Zenith®) patients was performed. Demographic data, anatomic characteristics, procedural details, and clinical outcome were analyzed. Pre-operative, post-operative (1 month), and longest follow-up CT scan at an average of 29.3 months for fEVAR and 29.8 months for sEVAR were analyzed using a dedicated 3D workstation (iNtuition, TeraRecon Inc, Foster City, California). Abdominal aortic aneurysm neck diameter was measured in 5 mm increments, ranging from 20 mm above to 20 mm below the lowest renal artery. Sub-analysis comparing the fEVAR to the sEVAR group at 12 months and at greater than 30 months was performed. Standard statistical analysis was done. RESULTS:Demographic characteristics did not differ significantly between the two cohorts. The fEVAR group had a larger mean aortic diameter at the lowest renal artery, shorter infrarenal aortic neck length, increased prevalence of nonparallel neck shape, and longer AAA length. On follow-up imaging, the suprarenal aortic segment dilated significantly more at all locations in the fEVAR cohort, whereas the infrarenal aortic neck segment dilated significantly less compared to the sEVAR group. Compared to the sEVAR cohort, the fEVAR patients demonstrated significantly greater positive sac remodeling as evident by more sac diameter regression, and elongation of distance measured from the celiac axis to the most cephalad margin of the sac. Device migration, endoleak occurrence, re-intervention rate, and mortalities were similar in both groups. CONCLUSION/CONCLUSIONS:Compared to sEVAR, 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 post-operative period as compared to sEVAR. Moreover, the fEVAR cohort had significantly greater sac shrinkage and improved aortic remodeling. The suprarenal seal zone in fEVAR may result in a previously undescribed increased level of protection against infrarenal neck dilatation. We hypothesize that the resultant decreased endotension conferred by better seal zone may be responsible for a more dramatic sac shrinkage in fEVAR.

BACKGROUND:The purpose of this study was to examine the incidence of acute kidney injury and chronic renal impairment following branched endovascular aneurysm repair (BEVAR) of complex thoracoabdominal aortic aneurysms (TAAA) using the Medtronic Valiant Thoracoabdominal Aortic Aneurysm stent graft system (MVM), the physician-modified Visceral Manifold, and Unitary Manifold stent graft systems. The objective was to report the acute and chronic renal function changes in patients following complex TAAA aneurysm repair. METHODS:This is an analysis of 139 patients undergoing branched endovascular repair for complex TAAAs between 2012 and 2020. Patient renal function was evaluated using serum creatinine and estimated glomerular filtration rate at baseline, 48 hr, discharge, 1 month, 6 months, and annually to 2 years. Patients on dialysis prior to the procedure were excluded from data analysis. RESULTS:A total of 139 patients (mean age 71.13; 64.7% male) treated for TAAA with BEVAR met inclusion criteria and were evaluated. A total of 530 visceral vessels were stented. A majority of patients (n = 131, 94.2%) underwent a single procedure while 8 required staged procedures. Thirty-day, 1-year and 2-year all-cause mortality rates were 5.8%, 25.2%, and 32.4%, respectively. Primary and secondary patency rates at a median follow-up of 26.9 months (95% CI; 21.1 - 32.7) were 96.2% and 97.5% for all vessels and 95.4% and 96.9% for renal arteries, respectively. Postoperative acute kidney injury (AKI) was identified in 22 (15.8%) patients. At discharge, 16 patients (11.6%) had an increase in CKD stage with 3 requiring permanent dialysis. Five additional patients required permanent dialysis over the 2-year follow-up period for a total of 8 (5.8%). Increasing age (HR = 1.0327, P= 0.0477), hemoglobin < 7 prior to procedure (HR = 2.4812, P= 0.0093), increasing maximum aortic diameter (HR = 1.0189, P= 0.0084), presence of AKI (HR = 2.0757, P= 0.0182), and increase in CKD stage (HR = 1.3520, P= 0.002) at discharge were significantly associated with decreased patient survival. CONCLUSIONS:Postoperative AKI and a chronic decline in renal function continue to be problematic in endovascular repair of complex aortic aneurysms. This study found that BEVAR using the manifold configuration resulted in immediate and mid-term renal function that is comparable to similar analyses of branched and/or fenestrated grafts.

OBJECTIVES/OBJECTIVE:Presence of an endoleak can compromise aneurysm exclusion after endovascular abdominal aortic aneurysm repair(EVAR). Type II endoleaks(T2Es) are most common and may cause sac expansion. We report outcomes of translumbar embolization(TLE) of T2Es following EVAR. METHODS:We conducted a retrospective chart review of patients with T2E after EVAR treated with TLE from 2011-2018 at a single academic institution. Treatment indications were the presence of persistent T2E and aneurysm growth ≥5mm. Sac stabilization was defined as growth ≤5mm throughout the follow-up period. RESULTS:Thirty consecutive patients were identified. The majority were men (n=24) with a mean age of 74.3 years (70.9-77.6, 95% CI). The most common comorbidities were hypertension (83.3%) and coronary artery disease (54.0%). The mean maximal sac diameter at T2E discovery was 5.8 cm (5.4-6.2, 95% CI). The mean time to intervention from endoleak discovery was 33.7±28 months with a mean growth of 0.84 cm (0.48-1.2, 95% CI) during that time period. The mean follow-up time after TLE was 19.1 months (11.1-27.2, 95% CI). Twenty-eight patients were treated with cyanoacrylate glue(CyG) alone, and 2 were treated with CyG plus coil embolization(CE). There was immediate complete endoleak resolution as assessed intraoperatively, and sac stabilization in 15 cases (50.0%). Eleven (36.7%) patients had evidence of persistent T2E on initial imaging after the embolization procedure; additional follow-up revealed eventual sac stabilization at a mean of 21.3±7.2 months and therefore these patients did not require further intervention. In the remaining four cases (13.3%) there was persistent T2E after the initial TLE requiring a second intervention. Repeat TLE stabilized growth in three of these four patients after a mean of 17.6±12.9 months. One patient required open sacotomy and ligation of lumbar vessels due to continued persistence of the T2E and continued aneurysm growth. There were no ischemic complications related to the embolization procedures. Factors associated with persistent endoleak after initial embolization were: larger aneurysm diameter at the time of initial endoleak identification (p<0.001), and the use of antiplatelet agents (p<0.02). The use of anticoagulation was not a significant risk factor for endoleak recurrence or aneurysm growth after TLE. CONCLUSIONS:TLE of T2E is a safe and effective treatment option for T2E with aneurysm growth following EVAR. Patients taking antiplatelet medication and those with larger aneurysms at the time of endoleak identification appear to be at increased risk for persistent endoleak and need for subsequent procedures following initial TLE. These patients may require more intensive monitoring and follow-up.

OBJECTIVES/OBJECTIVE:Venous thromboembolism, including deep venous thrombosis and pulmonary embolism, is a major source of morbidity, mortality, and healthcare utilization. Given the prevalence of venous thromboembolism and its associated mortality, our study sought to identify factors associated with loss to follow-up in venous thromboembolism patients. METHODS:-value of <0.05 set for significance. RESULTS: = 0.03) as opposed to home. CONCLUSIONS:Our study demonstrates that over one-third of patients diagnosed with venous thromboembolism at our institution are lost to venous thromboembolism-specific follow-up, particularly those discharged to a facility. Our work suggests that significant improvement could be achieved by establishing a pathway for the targeted transition of care to a venous thromboembolism-specific follow-up clinic.

OBJECTIVE: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, these data are derived from small single-institution experiences and the potential benefit of FLE remains unproven. In this study, we examined perioperative and midterm outcomes of patients with aortic dissection undergoing concomitant TEVAR and FLE.* METHODS: Patients 18 or older who underwent TEVAR for chronic aortic dissection with known FLE status in the Society for Vascular Surgery Vascular Quality Initiative database between January 2010 and February 2020 were included. Ruptured patients and emergent procedures were excluded. Patient characteristics, operative details and outcomes were analyzed by group: TEVAR with or without FLE. Primary outcomes were in-hospital post-operative complications and all-cause mortality. Secondary outcomes included follow-up mean maximum aortic diameter change, rates of false lumen thrombosis, re-intervention rates, and mortality. RESULTS: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, prior aortic interventions, mean maximum pre-operative aortic diameter (5.1cm vs. 5.0cm, P=0.43), 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). However, FLE was 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, IQR 2.2-36.2 months), all-cause mortality trended lower, but was not significant (2.2% vs. 7.8%); and Kaplan-Meier analysis demonstrated no difference in overall survival between groups (P=0.23). By Cox regression analysis, 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. CONCLUSIONS:Adjunctive FLE, despite increased procedural times, can be performed safely for patients with chronic dissection without significantly higher overall perioperative morbidity or mortality. TEVAR/FLE demonstrates trends for improved survival and increased rates of FL thrombosis in the treated thoracic segment; however, given the lack of evidence to suggest a significant reduction in re-intervention rates or induction of more favorable aortic remodeling compared to TEVAR alone, the overall utility of this technique in practice remains unclear. Further investigation is needed to determine the most appropriate role for FLE in managing chronic aortic dissections.

OBJECTIVE:Over the past two decades, the treatment of popliteal artery aneurysms (PAAs) has undergone a transformation. While open surgical repair (OR) remains the gold standard for treatment, endovascular repair (ER) has become an attractive alternative in select patient populations. The objective of this study was to compare the outcomes of open versus endovascular repair of PAAs at a single institution. METHODS:We performed a retrospective chart review of all patients between 1998 and 2017 who underwent repair for PAA. Patient baseline, anatomic, and operative characteristics as well as outcomes were compared between the open and endovascular cohorts. The intervention and treatment were at the discretion of the surgeon. RESULTS:Between 1998 and 2017, a total of 64 patients underwent repair of 73 PAAs at our tertiary care center. Twenty-nine patients with 33 PAAs underwent OR, and 35 patients with 40 PAAs underwent ER. When comparing the 2 cohorts, there were no statistically significant differences in demographic characteristics such as age, gender, or number of run-off vessels. There were significantly more patients in the ER group (21/53%) than the OR group (7/21%) with hyperlipidemia (p=.008) and a prior carotid intervention (6% vs. 0%, p=.029). Overall, the presence of symptoms was similar amongst the two groups; however, patients in the OR group had a significantly higher number of patients presenting with acute ischemia (p=.01). Length of stay (LOS) was significantly shorter in the ER cohort (mean 1.8 days [1-11]) compared to the OR group (5.4 days [2-13]) (p<.0001). There was no significant difference in primary or secondary patency rates between the two groups. In the ER group, good runoff (≥2 vessels) was a positive predictor for primary patency at 1 year (3.36 [1.0-11.25]), however, it was not in the OR group. Post-operative single and/or dual anti-platelet therapy did not affect primary patency in either cohort. CONCLUSIONS:The results of our study demonstrate that ER of PAAs is a safe and durable option with comparable patency rates to OR and a decreased LOS, with good run-off being a positive predictor for primary patency in the ER cohort.

Aortic mural thrombus in the absence of underlying aortic disease is rare and results in a risk of distant arterial embolization that can result in limb loss or other end organ damage. Current management involves open surgery, anticoagulation, and systemic thrombolysis; however, each carries inherent risks. We report the case of aortic thrombus with distal emboli in two patients, a 56-year-old man and a 68-year-old man, neither with underlying aortic pathology and both presenting with limb threatening ischemia. We performed percutaneous mechanical thrombectomy using the FlowTriever System (Inari Medical, Irvine, Calif) with successful removal of the aortic thrombus in both patients.

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:Transcarotid artery revascularization (TCAR) seems to be a safe and effective alternative to carotid endarterectomy (CEA) and transfemoral carotid artery stenting (TF-CAS). The TCAR system represents a paradigm shift in the management of carotid artery stenosis with potential for a significant decrease in periprocedural morbidity. However, as with CEA or TF-CAS, TCAR is associated with infrequent complications related to user technical error, most of which are preventable. Our goal is to describe these low-frequency events, and to provide guidelines for avoiding them. METHODS:The U.S. Food and Drug Administration (FDA) requires that all medical device manufacturers create a system for receiving, reviewing, and evaluating complaints (Code 21 of Federal Regulations 820.198). Silk Road Medical, Inc (Sunnyvale, Calif), has established a process by which all feedback, including complaints that may not meet FDA criteria, is captured and stored in a database for detailed analysis. More than 13,300 cases have been performed; submitted complaints were reviewed for incidents of serious injury and periprocedural complications, above and beyond the device-related events that must be reported to the FDA. RESULTS:A total of 13,334 patients have undergone TCAR worldwide between early 2011 and December 2019 using the SilkRoad device. Reported complications included 173 dissections (1.4% overall rate) of the common carotid artery at the access point, of which 22.5% were managed without intervention or with medical therapy alone and 24.3% were converted to CEA (considered failing safely). Errors in the location of stent deployment occurred in 16 cases (0.13%), with the most common site being the external carotid artery (75%). One wrong side carotid artery stent was placed in a patient with a high midline pattern of the bovine arch. Cranial nerve injury was reported in 11 cases (0.08%), only one of which persisted beyond 3 months. There have been three reported pneumothoraces and one reported chylothorax. Many of these errors can be recognized and prevented with careful attention to detail. CONCLUSIONS:In high-risk patients requiring treatment for carotid artery stenosis, TCAR has been proven as an alternative to TF-CAS with an excellent safety profile. As with CEA or TF-CAS, this procedure has the potential for infrequent complications, often as a result of user technical error. Although significant, these events can be avoided through a review of the collective experience to date and recognition of potential pitfalls, as we have described.