Faculty Bibliography

BACKGROUND:Mannitol is often administered during open juxtarenal or suprarenal aortic surgery to prevent ischemic injury to the kidneys. Prior evidence evaluating the benefits of intraoperative mannitol in reducing ischemia/reperfusion injury is conflicting and largely based on small, retrospective series. The aim of this study was to evaluate the effect of mannitol in preventing postoperative hemodialysis in patients undergoing open abdominal aortic aneurysm (AAA) repair where proximal control involved temporary renal ischemia. METHODS:The Society for Vascular Surgery Quality Initiative database was queried for all patients undergoing elective open AAA repair between 2003 and 2020. Patients were included in the current analysis if the proximal aortic clamp was placed above at least one renal artery. Chronic kidney disease (CKD) was defined as Cr > 1.8 mg/dL. Primary end points were 30-day major morbidity (myocardial infarction, respiratory complications, lower extremity or intestinal ischemia, and the need for temporary or permanent hemodialysis) and mortality. Comparisons were made between the mannitol and nonmannitol cohorts and stratified by the presence of preexisting CKD. RESULTS:During the study period, 4,156 patients underwent elective open AAA repair requiring clamp placement more than one (32.7%) or both (67.3%) renal arteries; 182 patients (4.4%) had preexisting CKD. Overall, 69.8% of patients received mannitol during their surgery. Mannitol was more frequently used in cases involving clamp placement above both renal arteries (70.3%) than one renal artery (61.5%). While prolonged ischemia time (more than 40 min) was associated with a higher risk of postoperative dialysis in patients without CKD, it was not significant in patients with baseline CKD. On a univariate analysis, mannitol use in patients with CKD was associated with a lower risk of postoperative dialysis (P = 0.005). This remained significant on a multivariate analysis (P = 0.008). Mannitol use did not appear to confer renal protective effects in patients without baseline CKD. CONCLUSIONS:Mannitol use was associated with a decreased risk of need for postoperative hemodialysis in patients with CKD undergoing suprarenal aortic clamping for open aneurysm repair. In appropriately selected patients, particularly those with underlying renal insufficiency, mannitol may confer a renal protective effect in open repair of pararenal AAA requiring suprarenal clamping.

Background: Interventions for carotid occlusions are infrequently undertaken and the outcomes are poorly defined. We sought to study patients undergoing urgent carotid revascularization for symptomatic occlusions.
Method(s): The Society for Vascular Surgery Vascular Quality Initiative was queried from 2003 to 2020 to identify patients with carotid occlusions undergoing carotid endarterectomy. Only symptomatic patients undergoing urgent interventions, defined within 24 hours of presentation, were included in this analysis. This cohort was compared to patients undergoing urgent intervention for severe stenosis (>=80%). Patients were identified based on computed tomography and magnetic resonance imaging, only. The primary end points were perioperative stroke, death, myocardial infarction (MI), and composite outcomes.
Result(s): A total of 390 patients were identified who underwent urgent carotid endarterectomy for symptomatic occlusions. The mean age was 67.4 +/- 10.2 years with a range from 39 to 90 years. The cohort was predominantly male (60%), and had significant risk factors for cerebrovascular disease, including hypertension (87.4%), diabetes (34.4%), coronary artery disease (21.6%), current smoking (38.7%), chronic obstructive pulmonary disease (21.6%), and congestive heart failure (10.3%). Medications included statin therapy (78.6%), P2Y12 inhibitors (32.0%), aspirin (77.9%) and renin-angiotensin inhibitor use (43.7%). The perioperative rate of neurologic events was 4.9%%, associated mortality was 2.8% and rate of MI was 1.0%. The composite end point of stroke/death/MI was 7.7%. When compared to patients undergoing urgent endarterectomy for severe stenosis (>=80%), the two cohorts were well matched with regards to risk factors, but the severe stenosis cohort appeared to be better medically managed based on reported medications. In the severe stenosis group, the perioperative rate of neurologic events was 3.3%, associated mortality was 0.9% and rate of MI was 1.2%. The perioperative outcomes were significantly worse for the carotid occlusion cohort, primarily driven by the perioperative mortality, which was nearly threefold, 2.8% versus 0.9% (P <.001). The composite end point of stroke/death/MI was also significantly worse in the occlusion cohort (7.7% vs 4.9%; P =.014).
Conclusion(s): Revascularization for symptomatic carotid occlusion constitutes approximately 2% of carotid interventions captured in the Vascular Quality Initiative, affirming the rarity of this undertaking. These patients have acceptable rates of perioperative neurologic events but are at an elevated risk of overall perioperative adverse events, primarily driven by a significantly higher mortality. While intervention for a symptomatic carotid occlusion may be performed with acceptable rate of perioperative complications, judicious patient selection is warranted in this high-risk cohort.
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Background: There is a paucity of data regarding outcomes of patients with premature cerebrovascular disease (<=55 years) who undergo carotid endarterectomy (CEA). The objective of this study was to analyze demographics, presentation, perioperative, and later outcomes of younger patients undergoing CEA.
Method(s): The Society for Vascular Surgery Vascular Quality Initiative was queried for CEA cases (2003-2020). Patients were stratified based on age 55 years or less or greater than 55 years. Primary end points were periprocedural stroke, death, myocardial infarction, and composite outcomes. Secondary end points analyzed included ipsilateral restenosis (>=80%) or occlusion, late ipsilateral neurologic events, and reintervention.
Result(s): Of 144,416 patients undergoing CEA, 8264 (5.7%) were aged 55 years or younger. The mean age was 51.3 years (range, 36 to 55 years). Younger patients were more likely to be female (44.5% vs 39.1%) and to be current smokers (58.8% vs 24.4%) (P <.001). They were less likely than older patients to have hypertension (82.2% vs 89.7%), coronary artery disease (25.6% vs 27.9%), and congestive heart failure (7.6% vs 11.2%; P <.001). Younger patients were less likely than older patients to be on aspirin, statins, or beta-blockers, but were more likely to be on P2Y12 inhibitors (P <.001). Younger patients were more likely to present with symptomatic disease (59% vs 47.2%) and were more likely to undergo nonelective CEA (19.3% vs 12.7%; P <.001). Younger patients had similar rates of perioperative stroke/death (1.8% vs 1.9%) and postoperative neurological events (1.7% vs 1.7%), but had lower rates of overall postoperative complications (3.8% vs 4.8%; P <.001). Sixty percent of patients had recorded follow-up (mean, 13 months). During follow-up, younger patients were significantly more likely than older patients to experience complete occlusion or significant (>=80%) restenosis of the operated artery (2.3% vs 1.6%), and were more likely to experience an ipsilateral neurological event (1.4% vs 0.9%) or any neurological event (3.2% vs 2.2%; P <.001).
Conclusion(s): Young patients undergoing CEA are more likely to be female, active smokers, and symptomatic. Although perioperative outcomes are similar, younger patients are more likely to experience carotid occlusion or restenosis as well as subsequent neurological events, during relatively short follow-up. These data suggest that younger CEA patients require more diligent follow-up, and a continued aggressive approach to medical management of atherosclerosis to prevent future events related to the operated artery.
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OBJECTIVE:Carotid artery plaque burden, indirectly measured by the degree of stenosis, quantifies future embolic risk. In natural history studies, patients with moderate degrees of stenosis have a lower stroke risk than those with severe stenosis. However, patients with symptomatic carotid stenosis who have experienced TIA or stroke are found to have both moderate and severe degrees of stenosis. We sought to examine the association carotid artery stenosis severity with outcomes in symptomatic patients undergoing carotid interventions including carotid endarterectomy (CEA), transfemoral carotid artery stenting (CAS) and transcervical carotid artery revascularization (TCAR). METHODS:The Society for Vascular Surgery Quality Initiative database was queried for all patients undergoing CAS, CEA and TCAR between 2003 and 2020. Patients were stratified into two groups based on the severity of stenosis - non-severe (0 - 69%) and severe (≥ 70%). Primary endpoints were periprocedural neurologic events (strokes and transient ischemic attacks (TIAs)). Secondary endpoints were periprocedural death, myocardial infarction (MI) and composite outcomes of stroke/death and stroke/death/MI per reporting standards for carotid interventions. RESULTS:Of 29,614 symptomatic patients included in the analysis, 5,296 (17.9%) patients underwent TCAR, 7,844 (26.5%) underwent CAS, and 16,474 (55.6%) underwent CEA for symptomatic carotid artery stenosis. In the CEA cohort, the neurologic event rate was similarly significantly lower in patients with severe stenosis when compared to those with non-severe stenosis (2.6% vs. 3.2%, P=.024). In the TCAR cohort, the periprocedural neurologic even rate was lower in patients with severe stenosis when compared to those with non-severe stenosis (3% vs. 4.3%, P=.033). There was no similar difference noted in the CAS cohort, with periprocedural neurologic event rates of 3.8% in the severe group versus 3.5% in the non-severe group (P=.518). On multivariable analysis, severe stenosis was associated with significantly decreased odds of post procedural neurologic events in patients undergoing CEA (odds ratio [OR] 0.75, 95% confidence interval [CI], 0.6 - 0.92; P=.007) and TCAR (OR .83; CI, .69 - 0.99; P=.039), but not CAS. CONCLUSION/CONCLUSIONS:Severe carotid stenosis as opposed to more moderate degrees of stenosis was associated with decreased rates of periprocedural stroke and TIAs in symptomatic patients undergoing TCAR and CEA, but not CAS. The finding of increased rates of periprocedural neurologic events in symptomatic patients with lesser degrees of stenosis undergoing TCAR and CEA warrants further evaluation with a particular focus on plaque morphology and brain physiology, and their inherent risks with carotid revascularization procedures.

Background: Prior studies have demonstrated that aneurysm sac expansion and failure of sac regression after endovascular aortic repair is associated with higher rates of late mortality and reinterventions. However, the effect of aneurysm sac remodeling on late outcomes after thoracic endovascular aortic repair (TEVAR) is not well-understood.
Method(s): We identified all patients who underwent TEVAR for degenerative aortic aneurysm in the VQI from 2011 to 2018 with 1-year follow-up imaging (+/-6 months) and linkage to Medicare claims data. Sac remodeling was defined as sac expansion (>=5 mm increase), sac stable (<5 mm change), or sac regression (>=5 mm decrease). Mid-term survival, rupture, and reintervention rates were also assessed using Kaplan-Meier estimates. Cox regression was used to assess the impact of sac behavior on midterm outcomes.
Result(s): Among 574 patients, 19% demonstrated sac expansion. Aortic diameter was smallest in patients with sac expansion (expansion 51 mm vs stable/regression 57 mm; P <.001). Sac expansion had the highest rate of any completion endoleak (13% vs 5%; P =.004) and type II completion endoleak (7.8% vs 2.2%; P =.006). An aortic diameter of 65 mm or greater was associated with higher odds of sac regression or stable sac (odds ratio [OR], 2.8; 95% confidence interval [CI], 1.2-6.7; P =.020), while any completion endoleak was associated with higher odds of sac expansion (OR, 3.4; 95% CI, 1.3-8.9; P =.010). Sac expansion trended toward a higher risk of 5-year mortality (21% vs 13%; adjusted hazard ratio, 1.8; 95% CI, 0.9-3.4; P =.079) (Figure) and late rupture (12% vs 4.6%; HR, 3.5; 95% CI, 0.9-13; P =.063). Additionally, sac expansion was associated with higher risk of late reintervention (78% vs 36%; adjusted hazard ratio, 3.0; 95% CI, 18-5.1; P <.001).
Conclusion(s): Sac expansion after TEVAR is associated with increased risk of mid-term rupture and reintervention. Furthermore, completion endoleak is associated with higher odds of sac expansion during follow-up. Further study is warranted to determine if shorter interval follow-up in patients at risk for sac expansion can improve late rupture rates in these patients. [Formula presented]
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OBJECTIVE:Vascular closure devices (VCDs) and manual compression (MC) are used to achieve hemostasis after peripheral vascular interventions (PVIs). We sought to compare perioperative outcomes between MC and four VCDs after PVI in a multicenter setting. METHODS:The Vascular Quality Initiative was queried for all lower extremity PVIs with common femoral artery access performed from 2010 to 2020. The VCDs included were MynxGrip (Cordis, Santa Clara, CA), StarClose SE (Abbott Vascular, Redwood City, CA), Angio-Seal (Terumo, Somerset, NJ), and Perclose ProGlide (Abbott Vascular). In a blinded fashion, these four VCDs (labeled A, B, C, and D) were compared to MC for baseline characteristics, procedural details, and outcomes (access site hematoma and stenosis/occlusion). Those with a sheath size >8F were excluded. Propensity score matching (1:1) was performed. Univariable and multivariable analyses were completed for unmatched and matched data. RESULTS:A total of 84,172 lower extremity PVIs were identified. Of these, 32,013 (38%) had used MC and 52,159 (62%) had used VCDs (A, 12,675; B, 6224; C, 19,872; D, 13,388). The average age was 68.7 years, and 60.4% of the patients were men. The most common indications for intervention were claudication (43.8%) and tissue loss (40.1%). Compared with MC, VCDs were used more often for patients with obesity, diabetes, and end-stage renal disease (P < .001 for all). VCDs were used less often for patients with hypertension, chronic obstructive pulmonary disease, coronary artery disease, prior percutaneous coronary and extremity interventions, and major amputation (P < .001 for all). VCD use was more common than MC during femoropopliteal (73% vs 63.8%) and tibial (33.8% vs 22.3%) interventions but less common with iliac interventions (20.6% vs 34.7%; P < .001 for all). Protamine was used less often with VCDs (19.1% vs 25.6%; P < .001). Overall, 2003 hematomas had developed (2.4%), of which 278 (13.9%) had required thrombin or surgical intervention. Compared with MC, the use of any VCD had resulted in fewer hematomas (1.7% vs 3.6%; P < .001) and fewer hematomas requiring intervention (0.2% vs 0.5%; P < .001). When divided by hemostatic technique, the rate of the development of any hematoma was as follows: MC, 3.6%; VCD A, 1.4%; VCD B, 1.2%; VCD C, 2.3%; and VCD D, 1.1% (P < .001). The rate of hematomas requiring intervention was as follows: MC, 0.5%; VCD A, 0.2%; VCD B, 0.2%; VCD C, 0.3%; and VCD D, 0.1% (P < .001). Access site stenosis/occlusion was similar between the MC and any VCD groups (0.2% vs 0.2%; P = .12). Multivariable analysis demonstrated that any VCD use and the use of the individual VCDs compared with MC were independently associated with the development of fewer hematomas. The incidence of access site stenosis/occlusion was similar between the use of any VCD and MC. The matched analysis revealed similar findings. CONCLUSIONS:Although the overall rates of hematomas requiring intervention were low regardless of hemostatic technique, VCD use, irrespective of type, compared favorably with MC, with significantly fewer access site complications after PVI.

Background: Preoperative renal function is a predictor of morbidity and mortality after endovascular repair of juxtarenal aortic aneurysms. However, the impact of postoperative renal complication on outcomes after repair are poorly understood. Therefore, our objective was to assess the impact of postoperative renal dysfunction on midterm outcomes following endovascular repair of juxtarenal aortic aneurysms.
Method(s): We identified all endovascular repairs of juxtarenal aortic aneurysms in the Vascular Quality Initiative from 2011 to 2018 with linkage to Medicare claims data. Juxtarenal aortic aneurysm repair was defined as repair with at least one scallop, fenestration, branch, or parallel grafting into a renal vessel. Postoperative renal complication was defined as acute kidney injury (AKI; >=0.5 mg/dL serum creatinine increase) or new renal replacement therapy (RRT). We excluded any patients on preoperative hemodialysis. Kaplan-Meier estimates and Cox regression were used to determine the effect of AKI/RRT on midterm mortality, rupture, and reintervention.
Result(s): Of 931 endovascular repairs, 17% experienced postoperative AKI/RRT. Repairs with postoperative AKI/RRT more often had coverage/occlusion of renal vessels (AKI/RRT: 17% vs stable function: 4.5%; P <.001) or parallel grafting of renal vessels (24% vs 16%; P <.001). Furthermore, repairs with postoperative AKI/RRT had higher rates of postoperative mortality (18% vs 1.2%; P <.001). Postoperative AKI/RRT was independently associated with a higher risk of 5-year mortality (42% vs 16%; adjusted hazard ratio [aHR] 2.4; 95% confidence interval [CI], 1.5-3.8; P <.001) (Figure) and 3-year late rupture (17% vs 5.1%; adjusted hazard ratio, 4.0; 95% CI, 1.8-8.8; P =.001). Meanwhile, postoperative AKI/RRT trended toward a higher risk of 3-year reinterventions (28% vs 20%; adjusted hazard ratio, 1.5; 95% CI, 0.9-2.5; P =.105).
Conclusion(s): Postoperative renal complications adversely impacted late mortality, rupture, and reintervention. Future studies with longer follow-up may likely demonstrate even worse outcomes in this cohort. Our study calls for optimization of preoperative renal status and the use of protective adjuncts to reduce the risk of postoperative renal complications and its negative long-term sequala. [Formula presented]
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Background: Thoracic endovascular aortic repair (TEVAR) is increasingly used to treat aortic dissections and aneurysms. Access-related complications remain a common source of morbidity and mortality following TEVAR. Therefore, this study aims to determine major risk factors predicting postoperative access complications and 3-year survival in patients with access complications.
Method(s): We identified all patients undergoing TEVAR in the Vascular Quality Initiative from July 2010 to August 2021, excluding those converted to open repair. We defined access complication as postoperative occlusion, wound infection, hematoma, or unplanned conversion to open cutdown. The primary outcome was 3-year survival and the secondary outcome was postoperative mortality. Mixed effects logistic regression modelling with physician level clustering was used to identify factors associated with access complications and postoperative mortality. Kaplan-Meier estimates and Cox proportional hazards models were used for analysis of three-year survival.
Result(s): Of 18,172 patients, 1584 (8.7%) had access complications. Bilateral percutaneous access was obtained in 68% of patients, one percutaneous and one open in 14%, and bilateral open access in 13%. Patients with access complications were older (70 +/- 0.6 years vs 66 +/- 0.2 years; P <.01) and female (50% vs 34%; P <.01). Patients with access complications experienced higher postoperative mortality (12% vs 4.6%; P <.01), major adverse cardiac event (17% vs 6.6%; P <.01), reintervention (22% vs 10%; P <.01), and spinal ischemia (7.0% vs 2.1%; P <.01). After adjustment, factors associated with access complication include female sex (odds ratio [OR], 2.2; 95% confidence interval [CI], 1.9-2.6; P <.01) and obesity (OR, 1.2; 95% CI, 1.0-1.4; P =.02). Access complication was independently associated with postoperative mortality (OR, 2.5; 95% CI, 2.0-3.0; P <.01). Bilateral cutdown was associated with lower mortality in male patients (OR, 0.55; 95% CI, 0.34-0.90; P =.02), but not in female patients (OR, 2.1; 95% CI, 1.1-4.3; P =.03). Last, access complications were associated with higher 3 -year mortality (hazard ratio, 1.6; 95% CI, 1.3-1.8; P <.01).
Conclusion(s): Access complications when unexpected are associated with adverse postoperative and three-year outcomes. Female sex is associated with higher rates of access complications, suggesting the need for devices tailored to female anatomy.
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INTRODUCTION/BACKGROUND:The proportion of open aneurysm repairs requiring at least a suprarenal clamp has increased in the past few decades, partly due to preferred endovascular approaches for most patients with infrarenal aneurysms, suggesting that the management of aortic clamp placement has become even more relevant. This study evaluated the association between proximal clamp site and intraoperative ischemia times with postoperative renal dysfunction and mortality. METHODS:We used the Vascular Quality Initiative to identify all patients undergoing open repairs of elective or symptomatic juxtarenal AAAs from 2004-2018 and compared outcomes by clamp site: above one renal artery, above both renal arteries (supra-renal), or above the celiac trunk (supra-celiac). Outcomes evaluated included acute kidney injury (AKI), new-onset renal failure requiring renal replacement therapy (RRT), 30-day mortality, and one-year mortality. We used multilevel logistic regressions and cox-proportional hazards models, clustered at the hospital level, to adjust for confounding. RESULTS:We identified 3976 patients (median age 71 years, 70% male, 8.2% non-Caucasian), with a median aneurysm diameter of 5.9cm (IQR 5.4-6.8cm). Proximal clamp sites were: above one renal artery (31%), supra-renal (52%), and supra-celiac (17%). Rates of unadjusted outcomes were 20.5% for AKI, 4.1% for new-onset RRT, 4.9% for 30-day mortality, and 8.3% for one-year mortality. On adjusted analyses, independent of ischemia time, supra-renal clamping relative to clamping above a single renal artery had higher odds of postoperative AKI (aOR 1.50 [95%-CI 1.28-1.75]) but similar odds for new-onset RRT (aOR 1.27 [0.79-2.06]) and 30-day mortality (aOR 1.12 [0.79-1.58]) and hazards for one-year mortality (aHR 1.12 [0.86-1.45]). However, every ten minutes of prolonged intraoperative ischemia time was associated with an increase in odds or hazards ratio of postoperative AKI by +7% (IQR 3-11%), new-onset RRT by +11% (IQR 4-17%), 30-day mortality by +11% (IQR 6-17%), and one-year mortality by +7% (IQR 2-13%). Patients with greater than 40 minutes of ischemia time had notably higher rates of all four outcomes. DISCUSSION/CONCLUSIONS:Supra-renal clamping relative to clamping above a single renal artery was associated with AKI but not new-onset RRT or 30-day mortality. However, intraoperative renal ischemia time was independently associated with all four postoperative outcomes. While further studies are warranted, our findings suggest that an expeditious proximal anastomosis creation is more important than trying to maintain clamp position below one renal artery, suggesting that suprarenal clamping may be the best strategy for open AAA repair when needed to efficiently perform the proximal anastomosis.

OBJECTIVES/OBJECTIVE:Endovascular aortic aneurysm repair (EVAR) has become the standard of care treatment for abdominal aortic aneurysms (AAA) in the modern era. While numerous devices exist for standard infrarenal AAA repair, fenestrated endovascular aneurysm repair (fEVAR) offers a minimally invasive alternative to traditional open repair in patients with short infrarenal necks. Over time, aortic neck dilation can occur leading to loss of proximal seal, endoleaks, and AAA sac growth. This study analyzes aortic remodeling following EVAR versus fEVAR and further evaluates whether fEVAR confers a benefit in terms of sac shrinkage. METHODS:A retrospective review of prospectively collected data on 120 patients undergoing EVAR was performed: 30 patients were treated with fEVAR (Cook Zenith© Fenestrated) and 90 patients were treated with EVAR devices (30 with each Medtronic Endurant ©, Gore Excluder ©, and Cook Zenith ©). Demographic data were recorded, and anatomic measurements were taken for each patient pre-operatively, 30 days post-operatively, and at the longest point of follow-up using three-dimensional reconstruction software. RESULTS:There were no significant differences in demographics data between the 4 groups. fEVAR was used more often in aortas with large necks and irregular morphology (p= 0.004). At the time of longest follow up, the suprarenal aorta encompassing 5, 10, and 15mm above the lowest renal artery (ALRA) dilated the most for fEVAR versus all EVAR groups. Despite this, the infrarenal segment tended to increase by the least, or even regress, for fEVAR compared to all EVAR groups, and was associated with the overall greatest proportion of sac shrinkage for the fEVAR group compared to Medtronic, Gore, and Cook devices, respectively (-13.90% vs. -5.75% vs. -2.31% vs. -4.68%, p=0.025). CONCLUSIONS:Compared to EVAR, patients treated with fEVAR had greater suprarenal dilation over time, consistent with an overall greater burden of disease in the proximal native aorta. However, the infrarenal segment dilated significantly less over time in the fEVAR group compared to all EVAR groups, suggesting that fEVAR may stabilize the infrarenal neck, promoting positive sac remodeling, as evidenced by the greatest degree of decrease in largest AAA diameter in the fEVAR group.