Male kidney-specific BMAL1 knockout mice are protected from K+-deficient, high-salt diet-induced blood pressure increases.

The circadian clock protein basic helix-loop-helix aryl hydrocarbon receptor nuclear translocator-like protein 1 (BMAL1) is a transcription factor that impacts kidney function, including blood pressure (BP) control. Previously, we have shown that male, but not female, kidney-specific cadherin Cre-positive BMAL1 knockout (KS-BMAL1 KO) mice exhibit lower BP compared with littermate controls. The goal of this study was to determine the BP phenotype and immune response in male KS-BMAL1 KO mice in response to a low-K+ high-salt (LKHS) diet. BP, renal inflammatory markers, and immune cells were measured in male mice following an LKHS diet. Male KS-BMAL1 KO mice had lower BP following the LKHS diet compared with control mice, yet their circadian rhythm in pressure remained unchanged. Additionally, KS-BMAL1 KO mice exhibited lower levels of renal proinflammatory cytokines and immune cells following the LKHS diet compared with control mice. KS-BMAL1 KO mice were protected from the salt-sensitive hypertension observed in control mice and displayed an attenuated immune response following the LKHS diet. These data suggest that BMAL1 plays a role in driving the BP increase and proinflammatory environment that occurs in response to an LKHS diet.NEW & NOTEWORTHY We show here, for the first time, that kidney-specific BMAL1 knockout mice are protected from blood pressure (BP) increases and immune responses to a salt-sensitive diet. Other kidney-specific BMAL1 knockout models exhibit lower BP phenotypes under basal conditions. A salt-sensitive diet exacerbates this genotype-specific BP response, leading to fewer proinflammatory cytokines and immune cells in knockout mice. These data demonstrate the importance of distal segment BMAL1 in BP and immune responses to a salt-sensitive environment.

A Tiered Mentorship Program to Integrate Medical Students Into Clinical Research Projects.

OBJECTIVE: Herein we describe the development, implementation, and growth of our Vascular Research Training Program (VRTP), emphasizing the intentional involvement of medical students in clinical research. METHODS: We developed a VRTP focusing on medical student engagement to encompass 4 pillars: ownership, mentorship, experience, and independence within the research process. The program is organized by clinical projects with an attending surgeon, surgical trainee (fellow or resident), and medical student comprising each research project team. The VRTP program sought to facilitate a culture of learning, accountability, and mentorship to engage and encourage medical student involvement in clinical research. RESULTS: We reviewed the productivity of our current vascular surgery faculty by reviewing divisional records of faculty publications and conducting a literature search for the period of 2012 to 2019. The pre-VRTP model produced 13 included manuscripts in 2012-2015 (3.25 per year), while the implemented VRTP model yielded 43 articles (10.75 per year) from 2016-2019. There was no significant change in the impact factor (pre-VRTP mean ± SD was 1.8 ± 1.0 vs 2.2 ± 1.1, P = .17). Medical student productivity rose from 1.3 to 2.7 publications, with a similar rise in the number of students participating in more than one manuscript from 2 to 14. CONCLUSIONS: Deliberate involvement of medical trainees as a member of the clinical research team has the potential to generate subsequent increases in research productivity and effective mentorships. Academic surgical divisions should consider organized and intentional involvement of medical students as an essential component of clinical research.

Spontaneous Thrombosis of an Isolated Internal Iliac Artery Aneurysm.

BACKGROUND: Isolated internal iliac artery aneurysms (IIAAs) are uncommon but potentially morbid lesions that are a challenge to monitor and treat. However, given the small numbers of reported cases and high rates of incidentally discovered lesions, the natural history of isolated IIAAs is not well characterized. This case describes an atypical and previously unreported spontaneous thrombosis of an isolated IIAA, a lesion typically thought to progressively enlarge and rupture. METHODS: Medical records and imaging studies were retrospectively reviewed with the approval of our Institutional Review Board. A single patient underwent fluoroscopic angiography followed by computed tomography (CT) angiography, with no subsequent operative intervention. RESULTS: An isolated 5.5 cm left IIAA was discovered incidentally on CT scan and subsequently seen with fluoroscopic pelvic angiography. Three weeks following initial angiography, repeat pelvic angiography and CT scan demonstrated spontaneous thrombosis of the aneurysm. CONCLUSIONS: Isolated IIAAs are conditions for which the natural history remains uncertain despite their potential risk for rupture and mortality. Spontaneous thrombosis of these lesions is possible, suggesting that the natural history as previously described warrants further consideration.

Successful Treatment of Acute Limb Ischemia Secondary to Iatrogenic Distal Embolization Using Catheter Directed Aspiration Thrombectomy.

Objective: Acute limb ischemia (ALI) due to thromboembolism is a limb- and life-threatening condition regularly encountered by vascular surgeons. Iatrogenic distal embolization is occasionally seen as a complication of various endovascular procedures. We present a series of four patients who developed ALI due to arterial embolization during cardiovascular procedures that were successfully treated via catheter directed aspiration embolectomy. Methods: Retrospective review of demographics, risk factors, and procedural outcomes was completed for 4 patients who presented with ALI due to distal embolization following cardiovascular procedures. All patients were successfully treated with catheter directed aspiration embolectomy using the Penumbra Indigo System (Penumbra Inc., Alameda, California). All patients had high-quality angiography demonstrating successful embolectomy and end-procedure patency. Results: Three patients presented with Rutherford 2A and one with Rutherford 2B ALI secondary to intraoperative distal embolization. Three patients presented with ALI secondary to distal embolization during peripheral vascular interventions, and one following emergent intra-aortic balloon pump (IABP) placement for myocardial infarction. All emboli were located in the infra-inguinal vasculature. Median post-operative ABIs were 0.94 (n = 4). Median length of stay was 2 days. There were no mortalities and no need for adjunctive fasciotomy, amputation, or bypass for limb salvage. All patients improved clinically after intervention, and returned to their reported pre-hospitalization functional status. Conclusion: All procedures achieved technical success with catheter-directed aspiration thrombectomy with or without adjunctive lysis. Catheter-directed aspiration embolectomy with the Penumbra Indigo System for ALI following an iatrogenic embolic event is a safe, less-invasive treatment option. The use of this technology may reduce the need for traditional open thrombectomy or thrombolytic therapy to address ALI.

Modeling variability in the inferior vena cava into fenestrated endografts for retrohepatic caval injuries.

OBJECTIVE: Injury of the retrohepatic inferior vena cava (IVC) is rare, but extremely fatal. Open repair of these injuries is challenging. Various maneuvers, including atriocaval shunting and total vascular isolation, have been described, but are poorly tolerated in the severely injured patient. Endovascular repair is an attractive alternative strategy, but effective hemostasis of complex injuries requires an endograft that excludes the injury while permitting flow from the hepatic veins. Unfortunately, IVC and hepatic vein anatomy is highly variable and has not been clearly described in injured patients. Our purpose was to characterize critical human IVC morphology in trauma patients, and develop the design parameters of an off-the-shelf fenestrated endograft intended for caval deployment. METHODS: One hundred consecutive adult trauma patients with an admission computed tomography scan including a portal venous phase of the abdomen were reviewed. Specific anatomic measurements including segmental IVC lengths and diameters were obtained. Multiple theoretical endografts were modeled to optimize caval coverage in the retrohepatic segment, assuming 10% to 40% oversizing for seal. RESULTS: This sample population had a mean age of 50 years, height of 173 cm, and weight 84 kg. Seventy-one percent were male and 89% had a blunt mechanism of injury. The median caval length from the renal veins to right atrium was 111 mm (interquartile range [IQR], 102-120 mm), diameter was 22 mm (IQR, 19-26 mm), and hepatic venous orifice area was 336 mm2 (IQR, 267-432 mm2). All patients had a landing zone of at least 12 mm in the suprahepatic and 10 mm in the suprarenal segments. Three models of graft length were developed to accommodate patients with segmental and overall dimensions in the smallest half, third quartile, and fourth quartile. These could provide 95% of patients with coverage of the retrohepatic segment without risk of hepatic or renal vein occlusion. Four graft diameters were developed for cross-sectional fit. Graft diameters of 20, 24, 30, and 38 mm could provide adequate coverage in, respectively, 11%, 35%, 49%, and 16% of patients. These combinations of graft length and diameter would accommodate 93% of patients. CONCLUSIONS: We defined human IVC morphology essential for endovascular therapy and developed parameters for fenestrated IVC endografts to address retrohepatic caval injuries in trauma patients. Although additional study and testing are required, this proof-of-concept study supports the hypothesis that exclusion of the most devastating retrohepatic IVC injuries can be achieved with a reasonable number of off-the-shelf fenestrated endografts. These findings form the basis for additional research toward the development of novel devices for endovascular therapy of these often lethal injuries.

Intraoperative Fragmentation and Retention of Endovascular Devices: Clinical Consequences and Preventative Strategies.

BACKGROUND: Expanded applications and increasing volumes of complex endovascular procedures have increased the risk of unintended intraoperative fragmentation and retention of catheters and sheaths. We describe a series of retained or fragmented endovascular devices, a quality improvement program to address this unmet need for improved detection of catheter fragmentation, and the results of this program. METHODS: Cases utilizing endovascular devices that resulted in a retained catheter fragment were identified and analyzed during divisional quality improvement review. One consistent area of concern was operating room (OR) staff unfamiliarity with verifying the integrity of an endovascular device. In response, a slide-based training protocol of focused, endovascular nursing education was implemented. Following perceived lack of improvement after this approach, we developed a handheld visual reference display of the tips of common catheters and sheaths. Staff was surveyed before and after intervention to assess the educational value of the display and the impact on staff device familiarity. RESULTS: All 4 described cases resulted in an unplanned return to the OR for retrieval of the fragmented catheter or sheath. No thromboembolic complications were observed, although associated intra-arterial thrombus was noted in 2 cases. Thirty-four OR nurses were polled to trial the visual reference display initiative, with 70% of those reporting primary surgical assignments outside of cardiovascular ORs. Introduction of the new visual reference display improved staff confidence in their ability to identify a broken device (2.4-3.7, P < .001). This improvement was most significant in OR staff with primary assignments in noncardiovascular services. CONCLUSION: Current OR standard operating procedures fail to address the potential for unintentionally retained catheters and wires during endovascular procedures. Our novel visual reference display of common endovascular items rather than conventional in-service training improved the ability of staff to identify device fragmentation at the time of the index procedure.

Considerations beyond Stenosis for Carotid Endarterectomy in Treating Free-Floating Thrombus of the Carotid Artery.

BACKGROUND: Free-floating thrombus (FFT) of the carotid artery is an uncommon condition that can present with neurologic symptoms, often in the setting of ischemic stroke. The literature pertaining to the incidence and optimal treatment of this condition is limited. Herein, we report our contemporary experience with FFT across a range of degrees of carotid stenosis. METHODS: Medical records and imaging studies from a single academic medical center from January 2016 to July 2018 were retrospectively reviewed. Patient demographics, presentation, treatment, and follow-up were abstracted. RESULTS: Six cases of FFT of the carotid artery with and without hemodynamically significant atherosclerotic disease were identified. All cases presented with ischemic stroke; one case had a hemorrhagic conversion. In each case, the FFT was visualized by at least one imaging modality including computed tomography angiography, magnetic resonance angiography, and duplex ultrasound. Three patients had >50% carotid stenosis and three had <50%. All cases were treated with endarterectomy. Four of the six patients received preoperative anticoagulation. There were no postoperative complications. Median follow-up was 252 days, with one case lost to follow-up. Four of the six patients have been without restenosis, recurrence of the thrombus, nor worsening or recurrent stroke on follow-up. The fifth patient developed restenosis but remained clinically stable. CONCLUSIONS: Although current society guidelines do not recommend carotid endarterectomy as first-line treatment for symptomatic patients with <50% stenosis, it may be indicated in the context of FFT.

A Novel Risk Score Predicts Operative Mortality After Acute Type A Aortic Dissection Repair.

BACKGROUND: Current stratification systems for patients presenting with acute type A aortic dissection rely on signs of malperfusion to predict mortality. The authors sought to develop an algorithm to readily risk stratify these patients using admission characteristics. METHODS: Two hundred sixty-nine consecutive patients who underwent type A repair between 2002 and 2015 were reviewed for easily obtainable preoperative demographics and laboratory values deemed a priori as potential predictors of operative mortality. Multiple logistic regression analysis was performed to determine independent significance, and linear regression was performed to generate the concomitant regression expression of the variables significant on bivariate analysis. RESULTS: Operative mortality was 16% (43/269) and was 29% (34/119) among patients who presented with malperfusion. Upon multivariate analysis, creatinine (p = 0.008), liver malperfusion (p = 0.006), and lactic acid level (p = 0.0007) remained independent significant predictors. Regression coefficients allowed the generation of a risk score as 5.5 × (lactic acid [mmol/L]) + 8 × (creatinine [mg/dL]) ± 8 (+ if liver malperfusion presents, - if no liver malperfusion). Upon receiver-operating characteristic curve analysis this model generated a c-statistic of 0.75. Operative mortality among patients within the lowest tertile (risk score < 7) was 4%, whereas patients in the middle (7 to 20) and highest (≥20) tertiles had mortality rates of 14% 37%, respectively. CONCLUSIONS: Although still requiring external validation, the innovative risk score presented necessitates knowledge of lactic acid, serum creatinine, and liver function tests. The algorithm predicts operative mortality with high accuracy and offers clinicians a novel tool to improve preoperative guidance and prognosis.

Blunt multifocal aortic injury with abdominal aortic intimointimal intussusception.

Blunt abdominal aortic injury is an infrequent occurrence after blunt trauma. The majority of these injuries result from deceleration forces sustained in motor vehicle collisions. Effects of these forces on the thoracic aorta are well described, but associated spinal compression or distraction can also lead to injury of the affixed abdominal aorta. We present a case of multifocal blunt thoracic and abdominal aortic injury with circumferential abdominal aortic dissection, resulting in aortoaortic intussusception associated with a thoracolumbar spinal injury. The unique diagnostic challenge and subsequent successful endovascular management of a rare nonocclusive abdominal aortic intussusception are herein discussed.

Contemporary Single-Center Experience With Prophylactic Cerebrospinal Fluid Drainage for Thoracic Endovascular Aortic Repair in Patients at High Risk for Ischemic Spinal Cord Injury.

OBJECTIVE: To review rates of permanent paraplegia and lumbar drain-related complications in patients undergoing thoracic endovascular aortic repair (TEVAR) surgery with prophylactic cerebrospinal fluid (CSF) drainage at the authors' institution. DESIGN: Retrospective cohort study. SETTING: Tertiary care, academic medical center. PARTICIPANTS: Patients who underwent TEVAR with a high risk for ischemic spinal cord injury and prophylactic lumbar CSF drainage over a 5-year period. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: One hundred and two patients underwent TEVAR with lumbar CSF drainage. Thirty-day mortality was 5.9%, and the rate of permanent paraplegia was 2%. Drain complications occurred in 4 (3.9%) patients, but no patient experienced permanent injury related to CSF drainage. Two patients in the cohort had complete resolution of paraplegia with increased CSF drainage and mean arterial blood pressure increases aimed to increase spinal cord perfusion pressure by 25%. A third patient experienced improvement in lower extremity strength but remained paraplegic, and a fourth patient demonstrated no improvement in symptoms. The 6 patients taking clopidogrel experienced no bleeding complications, and there were no apparent risk factors for bleeding in the 5 patients who had bloody drain output or in 1 patient who developed an epidural hematoma. CONCLUSION: Prophylactic CSF drainage was associated with low paraplegia and drain-related complication rates. These data further support the safety of prophylactic CSF drainage in patients undergoing TEVAR with a high risk for ischemic spinal cord injury.

Transcervical Carotid Artery Stenting Using a Prosthetic Arterial Conduit: Case Series of a Novel Surgical Technique.

We present a series of 4 patients with carotid restenosis following carotid endarterectomy (CEA) who underwent transcervical carotid artery stenting (CAS) using a novel prosthetic conduit technique. The patients were high risk for repeat CEA (short and obese necks) and had contraindications to transfemoral CAS (bovine arch, prior dissection). CAS was thus performed via a transcervical approach with a polytetrafluoroethylene conduit anastomosed to the proximal common carotid artery. The addition of a conduit allowed stent placement via a secure, stable platform. All patients recovered from their procedure without incident and are free from restenosis at follow-up.

Flow Reduction-Aided Thrombin Injection for Complex Femoral Pseudoaneurysms: Case Series and Review of the Literature.

BACKGROUND: Peripheral pseudoaneurysms are a known complication of vascular access procedures. Complex lesions-those with short, wide necks or other complex arrangements-would conventionally require open repair, but we believe that even these lesions could be managed with an endovascular approach. METHODS: Four patients with complex pseudoaneurysms were offered an open repair or thrombin injection with the use of flow-reducing balloons. RESULTS: In our series of 4 patients with complex pseudoaneurysms, all were safely treated with percutaneous thrombin injection in conjunction with endovascular flow reduction. All patients recovered from their procedures without incident and are free from recurrence at follow-up. CONCLUSIONS: Flow reduction-aided thrombin injection may have particular utility in complex femoral pseudoaneurysms, especially in a patient population that may not tolerate open repair. High-risk lesions may merit special consideration for this technique, and further study is warranted.

Continuous Flow Perfused Cadaver Model for Endovascular Training, Research, and Development.

BACKGROUND: Endovascular simulation employing computer, animal, and static models are common and useful adjuncts for teaching endovascular procedures and developing novel, complex endovascular techniques. Unfortunately, these models lack realistic haptic feedback and thus do not faithfully replicate many of the technical challenges associated with clinical endovascular procedures (e.g., arterial calcification, rigidity, and stenosis). We sought to develop a realistic and reproducible perfused cadaver model for endovascular training, device development, and research. METHODS: Fresh frozen, elderly (age 50-80 years) male cadavers were thawed and prepared for open dissection. The entire arterial tree (ascending aorta to femoral arteries) was dissected free and major branch vessels exposed. Sheaths were placed to allow outflow from selected vessels. A Dacron conduit was sewn to the ascending aorta to generate arterial inflow, which was provided by a centrifugal pump. Aortic aneurysms were created in the descending thoracic and abdominal aorta. Digital subtraction arteriography and various endovascular interventions were performed, including stent grafts and EndoAnchors deployment. RESULTS: Continuous antegrade flow was achieved in the thoracic, abdominal, iliac, and femoral segments. Open and percutaneous access at the femoral region was obtained with realistic back-bleeding and tactile feedback. Adequate, fluoroscopically documented flow was observed in both cannulated major and noncannulated smaller branches. We performed angiography with standard techniques via a pigtail catheter and contrast injector throughout the arterial system. Abdominal and thoracic endografts were deployed with appropriate angiographic guidance and realistic haptic feedback for both guidewire and stent grafts. Additional applications, including selective cannulation, aorto-iliac occlusive disease interventions, and anchor placement, were also successfully simulated. Finally, the model was used as a platform to test investigational devices. CONCLUSIONS: Our pressurized cadaver flow model successfully replicated multiple aspects of advanced endovascular procedures with haptic feedback. This novel human cadaver model allows for training and device development under clinically realistic conditions.

Defining the burden, scope, and future of vascular acute care surgery.

OBJECTIVE: The paradigm of acute care surgery has revolutionized nonelective general surgery. Similarly, nonelective vascular surgery may benefit from specific management and resource capabilities. To establish the burden and scope of vascular acute care surgery, we analyzed the characteristics and outcomes of patients hospitalized for vascular surgical procedures in Maryland. METHODS: A retrospective analysis of a statewide inpatient database was performed to identify patients undergoing noncardiac vascular procedures in Maryland from 2009 to 2013. Patients were stratified by admission acuity as elective, urgent, or emergent, with the last two groups defined as acute. The primary outcome was inpatient mortality, and secondary outcomes were critical care and hospital resource requirements. Groups were compared by univariate analyses, with multivariable analysis of mortality based on acuity level and other potential risk factors for death. RESULTS: Of 3,157,499 adult hospital admissions, 154,004 (5%) patients underwent a vascular procedure; most were acute (54% emergent, 13% urgent), whereas 33% were elective. Acute patients had higher rates of critical care morbidity and required more hospital resource utilization. Admission for acute vascular surgery was independently associated with mortality (urgent odds ratio, 2.1; emergent odds ratio, 3.0). CONCLUSIONS: The majority of inpatient vascular care in Maryland is for acute vascular surgery, which is an independent risk factor for mortality. Acute vascular surgical care entails greater critical care and hospital resource utilization and-similar to emergency general surgery-may benefit from dedicated training and practice models.

Management and outcomes of carotid artery extension of aortic dissections.

BACKGROUND: Aortic dissection (AD) is the most common aortic catastrophe. Carotid artery dissection due to extension of AD (CAEAD) is one severe complication of this condition. Despite years of refinement in the techniques for repair of AD, the optimal management strategy for CAEAD remains yet to be described. We hypothesized that CAEAD eventually resolves on antiplatelet therapy with a low but not insignificant risk of cerebrovascular accident (CVA). METHODS: This was a single-institution retrospective review of patients admitted with nontraumatic coincident aortic and carotid dissection between 2001 and 2013. RESULTS: CAEAD was present in 38 patients (24 men [53%]). The median age was 59.5 years (range, 25-85 years). A Stanford type A AD was diagnosed in 36 patients (95%). CVA or transient ischemic attack was identified in 11 patients (29%). Eight were potentially attributable to the carotid lesion. Two of these eight strokes resulted in death. Of the 11 CVAs and transient ischemic attacks, 8 were evident at presentation, 2 were diagnosed postoperatively during hospitalization, and 1 was diagnosed during early follow-up. Only one of these three postadmission strokes was attributable to the carotid lesion. Nonoperative management of aortic and carotid dissections was pursued in 9 patients (24%), 26 (68%) underwent open repair, and 4 (11%) had endovascular management of AD (2 thoracic endovascular aortic repair, 2 endovascular fenestrations), including 1 patient with a staged hybrid procedure (frozen elephant trunk). There were eight inpatient deaths (21%) and nine deaths in the follow-up period. Of the 30 patients who survived to discharge, 24 (80%) were managed with antiplatelet therapy. At a median follow-up of 14.5 months in 22 patients with follow-up computed tomography scans available, a minority of lesions had resolved, and only one CVA was reported. CONCLUSIONS: This study found that CAEAD was associated almost exclusively with type A AD, was typically unilateral, most often on the left, and usually persisted at follow-up. Many CAEAD patients presented with CVA and experienced significant early mortality. Notably, not all CVA events were attributable to the CAEAD. CVAs were not common after admission, and there appeared to be a low risk of new or subsequent stroke during follow-up with routine antiplatelet and antihypertensive therapy.

Functional status predicts major complications and death after endovascular repair of abdominal aortic aneurysms.

OBJECTIVE: Endovascular aneurysm repair (EVAR) is considered a lower risk option for treating abdominal aortic aneurysms and is of particular utility in patients with poor functional status who may be poor candidates for open repair. However, the specific contribution of preoperative functional status to EVAR outcomes remains poorly defined. We hypothesized that impaired functional status, based simply on the ability of patients to perform activities of daily living, is associated with worse outcomes after EVAR. METHODS: Patients undergoing nonemergent EVAR for abdominal aortic aneurysm between 2010 and 2014 were identified in the National Surgical Quality Improvement Program (NSQIP) database. The primary outcomes were 30-day mortality and major operative and systemic complications. Secondary outcomes were inpatient length of stay, need for reoperation, and discharge disposition. Using the NSQIP-defined preoperative functional status, patients were stratified as independent or dependent (either partial or totally dependent) and compared by univariate and multivariable analyses. RESULTS: Of 13,432 patients undergoing EVAR between 2010 and 2014, 13,043 were independent (97%) and 389 were dependent (3%) before surgery. Dependent patients were older and more frequently minorities; had higher rates of chronic pulmonary, heart, and kidney disease; and were more likely to have an American Society of Anesthesiologists score of 4 or 5. On multivariable analysis, preoperative dependent status was an independent risk factor for operative complications (odds ratio [OR], 3.1; 95% confidence interval [CI], 2.5-3.9), systemic complications (OR, 2.8; 95% CI, 2.0-3.9), and 30-day mortality (OR, 3.4; 95% CI, 2.1-5.6). Secondary outcomes were worse among dependent patients. CONCLUSIONS: Although EVAR is a minimally invasive procedure with substantially less physiologic stress than in open aortic repair, preoperative functional status is a critical determinant of adverse outcomes after EVAR in spite of the minimally invasive nature of the procedure. Functional status, as measured by performance of activities of daily living, can be used as a valuable marker of increased perioperative risk and may identify patients who may benefit from preoperative conditioning and specialized perioperative care.

Implications of concomitant hypogastric artery embolization with endovascular repair of infrarenal abdominal aortic aneurysms.

OBJECTIVE: Hypogastric artery embolization (HAE) is associated with significant risk of ischemic complications. We assessed the impact of HAE on 30-day outcomes of endovascular aneurysm repair (EVAR) of infrarenal abdominal aortic aneurysms. METHODS: We queried the American College of Surgeons National Surgical Quality Improvement Program database from 2011 to 2014 to identify and to compare clinical features, operative details, and 30-day outcomes of EVAR with those of concomitant HAE with EVAR (HAE + EVAR). Multivariate analysis was performed to determine preoperative and intraoperative factors associated with development of significant complications observed in patients with HAE + EVAR. RESULTS: In a cohort of 5881 patients, 387 (6.6%) underwent HAE + EVAR. Compared with EVAR, a higher incidence of ischemic colitis (2.6% vs 0.9%; P = .002), renal failure requiring dialysis (2.8% vs 1%; P = .001), pneumonia (2.6% vs 1.3%; P = .039), and perioperative blood transfusion (17% vs 13%; P = .024) was noted after HAE + EVAR. Thirty-day thromboembolic events, strokes, myocardial infarction, lower extremity ischemia, reoperation, and readmission rates were not significantly different (P > .05). Mortality at 30 days in HAE + EVAR patients was 4.1% compared with 2.5% with EVAR (P = .044). HAE was independently associated with increased risk of colonic ischemia (adjusted odds ratio, 2.98; 95% confidence interval, 1.44-6.14; P = .003) and renal failure requiring dialysis (adjusted odds ratio, 2.22; 95% confidence interval, 1.09-4.53; P = .029). However, HAE was not an independent predictor of mortality. Average length of hospital stay was 4 ± 8.5 days after HAE + EVAR vs 3.3 ± 5.9 days after EVAR (P = .001). CONCLUSIONS: Concomitant HAE with EVAR is associated with longer and more complicated hospital stays. Ischemic colitis is a rare complication of EVAR. HAE increases the risk of ischemic colitis and renal failure requiring dialysis. This study highlights the importance of hypogastric artery preservation during EVAR.

Management and outcomes of blunt common and external iliac arterial injuries.

OBJECTIVE: Blunt iliac arterial injuries (BIAI) require complex management but are rare and poorly studied. We investigated the presentation, management, and outcomes of patients with blunt common or external iliac arterial injuries. METHODS: We identified and reviewed 112 patients with BIAI admitted between 2000 and 2011 at a Level I trauma center. Patients with common/external iliac artery injuries (CE group) were primarily analyzed, with patients with injuries of the internal iliac artery or its major branches (IB group) included for comparison of pelvic arterial trauma. RESULTS: Twenty-four patients had CE and 88 had IB injuries. Mean ages (45 ± 19 years) and gender (86% male) were similar between groups. The mean injury severity score was 40 ± 14 (CE, 36 ± 15; IB, 40 ± 14; P = .19), indicating severe trauma. Twenty (83%) of the CE patients presented with signs of leg malperfusion. Admission factors associated with CE injury were crush mechanism of injury (37% vs 17%; P = .03) and pelvic soft tissue trauma (50% vs 15%; P < .01). The CE group had higher early mortality rates, both within 3 hours of admission (50% vs 19%; P = .04) and prior to iliac intervention (42% vs 3%; P < .01). Among those surviving to management, CE patients were more likely to undergo open repair or revascularization (68% vs 3%; P < .01) and had a higher rate of leg amputation (50% vs 6%; P < .01), with 8/12 (67%) culminating in hemipelvectomy. Risk factors for amputation included leg malperfusion, high-grade pelvic fractures, pelvic soft tissue trauma, and increasing leg injury severity. Overall mortality was 40%, and was similar between the injury groups. Among CE patients, need for amputation, pelvic fractures, and wounds were associated with inpatient mortality. CONCLUSIONS: This is the largest series to date of blunt CE injuries and demonstrates distinct clinical features and outcomes for these patients. They have high risk for early death and proximal leg amputation. CE injury is specifically associated with serious open pelvic soft tissue injury, which, along with high-grade pelvic fractures, is a risk factor for amputation and death. On-demand emergent endovascular intervention may play an important role in improving management of these complex injuries.

Patterns and management of blunt abdominal aortic injury.

BACKGROUND: Blunt abdominal aortic injury (BAAI) is historically associated with significant morbidity and mortality. Our institutional experience was analyzed to define current patterns of injury and to help guide management. METHODS: Adult patients with BAAI between January 2000 and July 2011 were identified from our trauma registry. Medical, radiographic, and autopsy records were reviewed for relevant clinical data. Management and outcomes were compared between patients with minimal aortic injury limited to the intima (MAI) compared to more significant aortic injury (SAI). RESULTS: Nine patients had MAI and 8 had SAI, including 2 dissections, 2 pseudoaneurysms, 2 branch avulsions, 1 thrombosis, and 1 transection. The MAI and SAI groups had similar demographics and patterns of injury, and all patients had significant polytrauma, with a mean injury severity score of 42. More MAI than SAI patients were managed nonoperatively (100% vs. 38%; P=0.01). All observed patients underwent repeat imaging during the index admission, 85% within 72 hours, and no observed lesions led to malperfusion, death, or progression during the index admission. One MAI progressed to a pseudoaneurysm within 8 months. Five SAI patients underwent aortic-related repairs, including 2 endovascular stent grafts, 2 open primary repairs, and 1 axillobifemoral bypass. Overall, 15 (88%) patients underwent procedures for any injury-9 required laparotomy (53%) and 2 underwent thoracotomy. There were 6 (35%) deaths, 2 attributable to aortic injury-1 from hemorrhage and 1 from hyperkalemic cardiac arrest after prolonged ischemia from infrarenal aortic occlusion. Among patients who survived the initial resuscitation, SAI was associated with a significantly higher mortality rate compared to MAI (50% vs. 0%; P=0.03). CONCLUSIONS: Patients with MAI are at low risk of complications and may be considered for observation. Patients with SAI requiring intervention manifest clinically and/or radiographically at presentation. Those not associated with bleeding, malperfusion, or thromboembolism may be observed with interval imaging. For all observed patients, long-term surveillance is required to document complete resolution or stability, because even MAI can progress to a more complex lesion.