Faculty Bibliography

BACKGROUND:While anemia in patients undergoing endovascular aortic repair (EVAR) has been associated with negative outcomes, the impact of transfusion remains unclear and controversial. This study evaluates the impact of postoperative anemia and red blood cell transfusion in patients undergoing complex EVAR (CEVAR) including fenestrated-branched and chimney EVAR. METHODS:The Society for Vascular Surgery Vascular Quality Initiative was queried for patients undergoing CEVAR with incorporation of 1 or more viscerorenal vessels from 2014 to 2020. Patients were grouped by postoperative nadir hemoglobin (Hgb) level (<7, 7-8, 8-9, 9-10, >10 g/dL), then stratified by transfusion status. The primary endpoint was major adverse cardiac events (MACE), including myocardial infarction, heart failure, dysrhythmia, and stroke. Secondary endpoints included in-hospital mortality and 1-year survival. RESULTS:In total, 4,966 patients met criteria for analysis including 9% with Hgb <7, 14% with Hgb 7-8, 16% with Hgb 8-9, 17% with Hgb 9-10, and 43% with Hgb >10. The rate of transfusion correlated inversely by lowest Hgb level: 89%, 74%, 40%, 21%, 6%, respectively. MACE, in-hospital mortality and 1-year survival correlated with Hgb level, with the worst outcomes in the lowest level. MACE was significantly higher for patients that received transfusion across all Hgb groups: 33.42% vs. 15.63%, P = 0.048; 23.38% vs. 14.04%, P = 0.008; 18.69% vs. 5.97%, P < 0.0001; 14.44% vs. 6.55%, P = 0.0006, and 13.08% vs. 3.43%, P < 0.0001, respectively. In-hospital mortality was significantly higher for patients that received transfusion in all groups except Hgb <7. On multivariable analysis transfusion remained an independent predictor for MACE and in-hospital mortality. CONCLUSION/CONCLUSIONS:Postoperative anemia in patients undergoing CEVAR is associated with worse outcomes. However, rather than attenuating the negative impact of anemia, transfusion is independently associated with increased MACE and in-hospital mortality. These findings suggest potential harm of liberal transfusion and support the practice of using a hemoglobin level of 7 g/dL as the threshold for transfusion in stable patients that are not actively bleeding. Further study is necessary to determine the optimal transfusion threshold for patients undergoing CEVAR.

OBJECTIVE:Spinal cord ischemia (SCI) remains one of the most devastating complications in both open and endovascular stent graft repair of thoracoabdominal aortic aneurysms. The endovascular aortic aneurysm repair (EVAR) can be either thoracic (TEVAR) when it targets the thoracic aortic aneurysm or fenestrated branched when repair involves the visceral and/or renal arteries. Even though EVAR interventions are less invasive than open repair, they are still associated with a significant risk of SCI. The current primary strategy to prevent SCI after TEVAR is to increase and/or maintain spinal cord perfusion pressure (blood flow) by increasing the mean arterial pressure while simultaneously draining CSF. Although the benefit of CSF drainage in EVAR procedures remains uncertain, it provides an opportunity to study the changes in cytokine and oxidative stress markers that may signal the pathophysiology of SCI following EVAR. The aim of this study was to evaluate the temporal relationship between stent deployment and CSF cytokine and oxidative stress marker levels as predictors of delayed SCI in patients undergoing an EVAR procedure. METHODS:There were 16 EVAR cases across 15 patients enrolled in this study, with 1 patient undergoing the procedure twice 1 year apart. The levels of oxidative stress (8-hydroxy-2'-deoxyguanosine [8-OHdG], glial fibrillary acidic [GFAP], and lactic acid) and proinflammatory (tumor necrosis factor-alpha [TNF-α], interleukin (IL)-6, and IL-1β) and antiinflammatory (IL-4) markers were quantified at different time points between 0 and 48 hours after EVAR by enzyme-linked immunosorbent assay. The changes in protein levels of both oxidative stress and inflammatory markers were expressed as fold change from the time of the lumbar drain insertion prior to surgery. RESULTS:Following the EVAR procedure, 8-OHdG resulted in the highest upregulation at later time points postoperatively (48 hours) and this increase was positively correlated with TNF-α level. The data also revealed that IL-6 peaked during the stent deployment intervention and this pattern of expression was positively correlated with the expression of lactic acid. No significant changes were noted in the expression levels of GFAP, lactic acid, and IL-1β. CONCLUSIONS:There appears to be a temporal relationship between lumbar CSF drainage and CSF cytokines and oxidative stress markers that may help 1) identify patients at risk for developing delayed SCI and 2) modify patient management to prevent the damage from delayed SCI.

BACKGROUND:Cerebral hyperperfusion syndrome (CHS) is a rare but serious complication following carotid artery revascularization. Considering the varying rates observed among carotid endarterectomy (CEA), Transfemoral Carotid Artery Stenting (TFCAS), and Transcarotid Artery Revascularization (TCAR), identifying the predictors and complications of CHS is essential for improving patient outcomes. This study utilizes a national database to investigate the predictors and complications of CHS following carotid revascularizations. METHODS:We conducted a retrospective analysis of all patients undergoing CEA, TFCAS, and TCAR for carotid artery stenosis in the Vascular Quality Initiative database from 2020 to 2023. Multivariate logistic regression was applied to identify CHS predictors, which were used to develop a risk score calculator. Moreover, we compared the stroke and mortality rates following CHS among the 3 revascularization techniques. RESULTS:The final cohort in our study included 59,130 (53%) CEAs, 14,064 (13%) TFCAS's, and 37,565 (34%) TCARs. There were 281 cases of CHS (0.25%), and TFCAS was associated with the highest rate of CHS (0.78% vs. 0.22% vs. 0.15%; P < 0.001). After adjusting for potential confounders, TFCAS was associated with almost 3-fold higher risk compared to CEA (adjusted odds ratio (aOR) = 2.87 [95% confidence interval (CI): 1.65-4.9] P < 0.001). On the other hand, TCAR was comparable to CEA. Other predictors of CHS included uncontrolled hypertension, insulin-dependent diabetes, symptomatic status, prior carotid procedure, urgent intervention, and postoperative blood pressure medication. These predictors were used to develop an interactive CHS risk calculator (C-statistic = 0.8). Among patients who developed CHS, TFCAS was associated with a 70% higher risk of inhospital stroke (aOR = 1.7 [95% CI: 1.4-2] P < 0.001) and almost triple the risk of inhospital death (aOR = 2.9 [95% CI: 2.3-3.8] P < 0.001). TCAR and CEA were comparable except for a slight risk of inhospital stroke after TCAR (aOR = 1.2 [95% CI: 1-1.3] P = 0.03). CONCLUSION/CONCLUSIONS:In this multi-institutional national study, we have demonstrated that the type of carotid revascularization significantly influences the risk of CHS and subsequent stroke and mortality, with TFCAS associated with the highest risk. Uncontrolled hypertension was associated with a 2-fold increased risk of CHS, underscoring the importance of tight blood pressure control. We were able to provide a prediction model for CHS based on preoperative factors. Prospective use of this risk calculator might benefit in postoperative monitoring.

BACKGROUND:Treatment of iliac artery aneurysms (IAAs) with the iliac branch endoprosthesis (IBE) during endovascular repair of infrarenal abdominal aortic aneurysm (endovascular aortic repair (EVAR)) has been well-documented as effective. However, limited data exist evaluating the safety and efficacy of treating complex abdominal (cAAAs) and thoracoabdominal aortic aneurysms (TAAAs) with associated IAA with combined physician-modified fenestrated-branched EVAR (PM-FBEVAR) and IBE. Moreover, limited studies exist assessing the impact of adding IBE on the outcomes following PM-FBEVAR. Therefore, we compared the clinical outcomes of patients who underwent PM-FBEVAR with and without IBE for the treatment of cAAA and TAAA. METHODS:A single-institution retrospective review of consecutive patients who underwent PM-FBEVAR between September 2015 and February 2021 was conducted. Patients with both unilateral and bilateral IBE implantation were included. Infected aneurysms and pseudoaneurysms were excluded. Demographics, technical success, and operative factors were analyzed. Primary outcomes were incidence of pelvic ischemia including buttock and thigh claudication, bowel and spinal cord ischemia, patency of internal and external limbs of IBE, and target vessel instability. Secondary outcomes included technical success, 30-day major adverse events, 30-day and all-cause mortality, and endoleaks. RESULTS:Among 183 patients identified who underwent PM-FBEVAR, 22 patients underwent PM-FBEVAR and IBE with 3 patients treated with bilateral IBEs. There was no pelvic ischemia in the PM-FBEVAR and IBE group. Technical success, fluoroscopy time, and procedure time were comparable between the 2 groups. Contrast usage was higher in the PM-FBEVAR and IBE group (P = 0.01). Thirty-day major adverse event and mortality were not statistically different between the 2 groups. At a mean follow-up of 23 months, all-cause mortality was similar for both groups (21% vs. 27%; P = 0.47). Patency of internal iliac artery limb and external iliac artery limb of the IBE were 96% (24 of 25) and 100%, respectively, during mean follow-up of 23 months. The patient with occlusion of internal iliac limb was asymptomatic and received no reintervention. CONCLUSIONS:Treatment of cAAA and TAAA associated with IAA using combined PM-FBEVAR and IBE is feasible with high efficacy and safety, and without adverse effect on outcomes. Long-term follow-up is planned to assess durability of repair with PM-FBEVAR and IBE.

BACKGROUND:Several recent small trials have suggested that there is a potential benefit of early thoracic endovascular aortic repair (TEVAR) for acute type B aortic dissection (TBAD), even for uncomplicated patients. We studied patients enrolled in the Gore Global Registry for Endovascular Aortic Treatment (GREAT) to compare outcomes of TEVAR in the early-acute phase with and without complicated presentation. METHODS:The GREAT registry was queried for patients treated with TEVAR for TBAD. Acute phase of TBAD was defined as hospitalization within 14 days of symptom onset. Time to treatment was computed as time from first symptoms to time of TEVAR implantation regardless of the preoperative duration of hospitalization. Complicated presentation of acute TBAD was designated by the treating clinical sites, and treatment strategy was determined at the physician's discretion, as was common practice at the time of registry conception in 2010; therefore, the designation of "complicated" presentation in this study differs from the most recent Society for Vascular Surgery/Society of Thoracic Surgeons reporting standards, which refers exclusively to malperfusion and rupture. All patients received TEVAR with Gore TAG or CTAG devices (W.L. Gore & Associates, Flagstaff, Arizona). The primary exposure variable was time from symptom onset to TEVAR, stratified by complicated versus uncomplicated presentation. The primary outcome was postoperative aortic complications, defined as endoleak, extended or new dissection (including retrograde type A dissection), rupture, enlargement or aneurysmal degeneration, requirement for reinterventions, conversion to open repair, and graft infection. Univariate data were analyzed by contingency table and unpaired t-test or Wilcoxon rank sum, and adjusted analyses were conducted using stratified and multiple logistic and Cox regression techniques. Data were analyzed by an independent academic research team. RESULTS:Of the 5,014 patients enrolled in the GREAT registry between 2011 and 2016, there were 172 patients who received TEVAR for TBAD; 40 of 172 (23%) were female and the mean age was 61 ± 12 years. There were 102 (59%) with complicated presentations. After adjustment for complicated presentation, TEVAR performed within 3 days of symptom onset was independently associated with increased rate of short-term (odds ratio, 2.4, P < 0.039), and intermediate-term (hazard ratio 2.31, P < 0.024) aortic complications. TEVAR performed within 3 days was also associated with increased rates of aortic reinterventions, branch vessel complications, renal complications, and aortic complication/death at 6 months when compared with delayed repair. CONCLUSION/CONCLUSIONS:These data suggest that TEVAR performed at least 3 days after acute TBAD is associated with less morbidity and mortality. When possible, TEVAR should be delayed by at least 3 days for patients with uncomplicated acute TBAD to offer maximum risk reduction.

OBJECTIVE:Open thoracoabdominal aortic aneurysm (TAAA) repair has been associated with high morbidity and mortality before the endovascular era, when repair options were limited. Our institution developed a multidisciplinary protocol to standardize patient selection, operative technique, and postoperative care to improve outcomes for open repairs. This study aimed to evaluate the protocol's preliminary benefits by comparing the outcomes of open TAAA repair on the protocol vs off the protocol. METHODS:A retrospective review of consecutive patients who underwent TAAA repair at a single institution from 2013 to 2023 was completed. Patients who underwent open repair were included and stratified by use of the protocol. The primary outcome was a composite of TAAA life-altering events, including in-hospital mortality, spinal cord ischemia with paraplegia, new onset of dialysis, or stroke. Secondary outcomes included each individual component, length of stay, and nonhome discharge. RESULTS:During the study period, 220 patients underwent TAAA repair at our institution, 190 endovascular and 30 open. There were 14 in the protocol group and 16 in the nonprotocol group. Patient demographics were similar between groups with an overall mean age of 46 years. A connective tissue disorder was present in 64% and 50% (P = .431) of protocol and nonprotocol patients, respectively. The majority of the patients in both groups presented with extent II TAAA (64% vs 75%). The composite end point occurred in 0% of the protocol group vs 38% of the nonprotocol group (P = .010). Secondary outcomes were dialysis (0% vs 19%; P = .23), paraplegia (0% vs 19%; P = .232), stroke (0% vs 0%), in-hospital mortality (0% vs 13%; P = .171), and nonhome discharge (7% vs 50%; P = .012). The median postoperative length of stay was 8 days vs 15 days (P = .038). CONCLUSIONS:In the endovascular era, open TAAA repair can be performed with encouraging outcomes when particular attention is given to patient selection, surgical technique, and postoperative care, with rates of mortality, paraplegia, renal failure, and length of stay that rival endovascular repair.