Guidelines for the treatment of abdominal aortic aneurysms. Report of a subcommittee of the Joint Council of the American Association for Vascular Surgery and Society for Vascular Surgery

The removal of all proximal aneurysmal aortic tissue does not affect anastomotic degeneration after open juxtarenal aortic aneurysm repair

OBJECTIVE

For the open treatment of juxtarenal aortic aneurysms (JRAAs), some argue for the removal of all proximal aneurysmal aortic tissue to prevent future degeneration, whereas others deem it unnecessary. This study sought to compare perioperative and long-term outcomes of two different approaches to treatment of JRAAs.

METHODS

Patients who underwent open JRAA repair from 2007 to 2015 at our institution were reviewed and stratified by operative technique: plication of the aneurysm cuff with graft sewn up to the renal arteries (PLI) vs a beveled anastomosis with left renal artery bypass (LRB). Patients who underwent additional mesenteric bypasses were excluded. Primary outcomes included death, anastomotic degeneration, and decline in renal function. Univariate and Kaplan-Meier analyses were performed.

RESULTS

There were 199 patients identified, 56% PLI (n = 112) and 44% LRB (n = 87). The majority were male (68%), white (89%), and smokers (58%). Mean age was 71.5 ± 8.5 years. LRB patients were more likely to have chronic kidney disease (29% vs 13%; P = .01) and larger juxtarenal diameters (median, 25 mm vs 28 mm; P = .001). LRB patients had longer postoperative length of stay (median, 8 days vs 7 days; P = .003) and longer operative times (median, 4.7 hours vs 3.7 hours; P < .001). Overall 30-day mortality was 2% (n = 4), with no difference between cohorts. There were no differences in perioperative complications except for the development of acute kidney injury, which was more common in LRB patients (47% vs 23%; P < .001). During 3-year follow-up, there was no difference in anastomotic aneurysmal degeneration or sac growth. In the long term, LRB patients were more likely to develop an occluded left renal artery (20% vs 0%; P = .004) and right renal artery stenosis (29% vs 3%; P = .002). However, neither group was more likely to have a decline in renal function (PLI, 23%; LRB, 25%; P = .84). There was no difference in 5-year mortality (P = .72).

CONCLUSIONS

The more complex technique involving LRB was not protective against long-term anastomotic degeneration, decline in renal function, or mortality. In addition, LRB led to longer length of stay and operative times, with increased risk of perioperative acute kidney injury. In an era when fewer open aortic repairs are being performed, it is reasonable to consider the PLI technique in the treatment of JRAAs, particularly in patients with baseline chronic kidney disease.

Deep vein thrombosis secondary to abdominal aortic aneurysm: A case report

RATIONALE

Abdominal aortic aneurysm is an extremely rare cause of deep vein thrombosis. Here we report an elderly gentleman who presented with deep vein thrombosis and was found to have concomitant abdominal aortic aneurysm upon ultrasonographic screening. It illustrates the possibility of such an aetiology, and the importance of screening for such aneurysms in a select patient population before heparinization.

PATIENT CONCERNS

A 73-year-old Asian gentleman with underlying hypertension, hyperlipidaemia, chronic renal failure, and history of chronic smoking presented to the emergency department with acute left lower limb swelling of 1 day. On examination, the patient was tachycardic (110 beats/minute) and hypertensive (168/84 millimeters mercury (mmHg)). The entire left lower limb was swollen with notable pitting oedema, tenderness, and warmth; left calf swelling was measured to be 4 centimeters (cm).

DIAGNOSES

The patient's Wells score of 4 placed him in the high-risk group for deep vein thrombosis. Serum D-dimer was subsequently found to be elevated at 926 nanograms/milliliter (ng/ml). Compression ultrasonography revealed a thrombus in the left deep femoral vein, confirming the diagnosis of deep vein thrombosis. The ultrasonographic evaluation was extended to the abdominal aorta due to the patient's high risk of abdominal aortic aneurysm, and a 7-cm aneurysm was indeed found. Further computed tomography and magnetic resonance imaging localized it to the infrarenal region, with left common iliac vein compression resulting in stagnant venous return.

INTERVENTIONS

Emergency endovascular repair was performed with insertion of an inferior vena cava filter.

OUTCOMES

The patient was subsequently monitored in the intensive care unit and uneventfully discharged after 2 weeks.

LESSONS

Such clinical presentations of deep vein thrombosis are rare, but physicians are reminded to consider screening for abdominal aneurysms and other anatomical causes before heparinization in patients who seemingly do not have thromboembolic risk factors. This is especially so for the high risk group of male deep vein thrombosis patients aged 65-75 years with a history of smoking who have yet to be screened for abdominal aortic aneurysms, in line with United States Preventive Services Task Force recommendations.

Imatinib prevents elastase-induced abdominal aortic aneurysm progression by regulating macrophage-derived MMP9

Abdominal aortic aneurysm (AAA) is characterized with progressive weakening and considerable dilation of the aortic wall. Despite the high risk of mortality in the elderly population, there are still no clinical pharmacological therapies to alleviate AAA progression. Macrophage-derived MMP9 acts as a key factor in extracellular matrix degradation and is crucial for aortic aneurysm development and aortic rupture. Here, we demonstrated that the transcription level of MMP9 was suppressed with a concentration-dependent manner in macrophages after Imatinib treatment, which was accompanied by the down-regulation of MMP9 protein expression and reduced MMP9 secretion in vitro. Imatinib administration (50 mg/kg/d, i.g.) was carried out one week after the establishment of elastase-induced AAA in rats, stabilizing aneurysm progression and improving survival rate via decreasing the aortic diameter and preventing elastin degradation. Expression and activity of MMP9 in the artery tissues were significantly suppressed after Imatinib treatment via in situ assessment like immunohistochemistry and zymography, although macrophage infiltration was not affected. Furthermore, we found that Imatinib inhibited MMP9 transcription through reduction of STAT3 phosphorylation and translocation from nucleus to cytoplasm. These observations indicated that Imatinib prevents aneurysm progression by inhibiting STAT3-mediated MMP9 expression and activation, suggesting a new application of Imatinib on AAA clinical therapy.

Results from a prospective multicenter feasibility study of Zenith p-Branch stent graft

OBJECTIVE

To evaluate the Cook Zenith p-Branch stent graft (William A. Cook Australia, Brisbane, Queensland, Australia) for the treatment of patients with asymptomatic juxtarenal or pararenal abdominal aortic aneurysms in a prospective, nonrandomized, multicenter, feasibility study conducted in the United States.

METHODS

The off-the-shelf p-Branch endograft incorporates a celiac scallop, superior mesenteric artery (SMA) fenestration, and two conical-shaped pivot renal fenestrations. Patients were eligible if the aneurysm did not extend above the distal margin of the SMA and the anatomy of renal and visceral arteries were compatible with one of the two p-Branch configurations (configuration A, renal fenestrations at the same longitudinal position; configuration B, offset renal fenestration).

RESULTS

A total of 30 patients (93% men; mean age, 73 years; mean aneurysm diameter, 64.7 ± 11.4 mm) were enrolled from January 2013 to June 2015. The mean follow-up period was 28.7 ± 12.5 months (as of October 2017). The technical success rate was 93% (28/30), with technical failure occurring in the first two study cases (device deliberately repositioned below the renal arteries because of difficulty in cannulating the renal arteries in one and an inability to place a renal stent in the other; both patients survived the procedure and withdrew from the study before the 12-month follow-up visit). No additional technical failures occurred after these first two cases, when an updated physician training and proctoring program was implemented. No 30-day mortality occurred. Of the remaining 28 patients, three died during the follow-up period; none within 30 days and none related to the device or procedure as determined by Clinical Events Committee adjudication. No treated aneurysm ruptures, conversion, or core laboratory-reported migration, or stent fracture were reported. The primary renal artery patency (interval to occlusion or reintervention for stenosis) rate was 88.6% ± 4.4% at 1 and 2 years. Two patients (7%) developed renal insufficiency secondary to a right renal artery stenosis in one patient and progression of chronic renal insufficiency in one patient. No patient required dialysis or developed mesenteric ischemia. Of the 28 patients, nine (32%) had undergone 13 secondary interventions for renal artery occlusion (n = 2), SMA occlusion (n = 1), renal or SMA stenosis (5 interventions in 4 patients), renal stent kinking (n = 1), lower extremity claudication (n = 2 in the same patient), type III endoleak between the p-Branch and renal stent (n = 1), and type II endoleak (n = 1).

CONCLUSIONS

These early and intermediate results, which incorporated physician learning curves, support the safety and feasibility of the off-the-shelf Zenith p-Branch device. Follow-up examinations through 5 years will continue to assess the long-term results.

Development and growth trends in angiotensin II-induced murine dissecting abdominal aortic aneurysms

Abdominal aortic aneurysms are pathological dilations that can suddenly rupture, causing more than 15,000 deaths in the U.S. annually. Current treatment focuses on observation until an aneurysm's size warrants surgical intervention. Thus, there is a need for therapeutic intervention to inhibit growth of smaller aneurysms. An experimental aneurysm model that infuses angiotensin II into apolipoprotein E‐deficient mice is widely used to investigate underlying pathological mechanisms and potential therapeutics, but this model has two caveats: (1) aneurysms do not always form, and (2) aneurysm severity and growth is inconsistent among animals. Here we use high‐frequency ultrasound to collect data from angiotensin II‐induced aneurysms to develop prediction models of both aneurysm formation and growth. Baseline measurements of aortic diameter, volume/length, and strain were used with animal mass and age in a quadratic discriminant analysis and logistic regression to build two statistical models to predict disease status. Longitudinal ultrasound data were also acquired from mice with aneurysms to quantify aneurysm diameter, circumferential strain, blood flow velocity, aneurysm volume/length, and thrombus and open‐false lumen volumes over 28 days. Measurements taken at aneurysm diagnosis were used with branching artery information to produce a multiple linear regression model to predict final aneurysm volume/length. All three statistical models could be useful in future aneurysm therapeutic studies to better delineate the effects of preventative and suppressive treatments from normal variations in the angiotensin II aneurysm model.

The role of tissue remodeling in mechanics and pathogenesis of abdominal aortic aneurysms

Arterial walls can be regarded as composite materials consisting of collagen fibers embedded in an elastic matrix and smooth muscle cells. Remodeling of the structural proteins has been shown to play a significant role in the mechanical behavior of walls during pathogenesis of abdominal aortic aneurysms (AAA). In this study, we systematically studied the change in the microstructure, histology and mechanics to link them to AAA disease progression. We performed biaxial extension tests, second-harmonic generation imaging and histology on 15 samples from the anterior part of AAA walls harvested during open aneurysm surgery. Structural data were gained by fitting to a bivariate von Mises distribution and yielded the mean fiber direction and in- and out-of-plane fiber dispersions of collagen. Mechanical and structural data were fitted to a recently proposed material model. Additionally, the mechanical data were used to derive collagen recruitment points in the obtained stress-stretch curves. We derived 14 parameters from histology such as smooth muscle cell-, elastin-, and abluminal adipocyte content. In total, 22 parameters were obtained and statistically evaluated. Based on the collagen recruitment points we were able to define three different stages of disease progression. Significant differences in elastin content, collagen orientation and adipocyte contents were discovered. Nerves entrapped inside AAA walls pointed towards a significant deposition of newly formed collagen abluminally, which we propose as neo-adventitia formation. We were able to discriminate two types of remodeled walls with a high collagen content - potentially safe and possibly vulnerable walls with a high adipocyte content inside the wall and significant amounts of inflammation. The study yielded a hypothesis for disease progression, derived from the systematic comparison of mechanical, microstructural and histological changes in AAAs. STATEMENT OF SIGNIFICANCE: Remodeling of the structural proteins plays an important role in the mechanical behavior of walls during pathogenesis of abdominal aortic aneurysms (AAA). We analyzed changes in the microstructure, histology and biomechanics of 15 samples from the anterior part of AAA walls and, for the first time, linked the results to three different stages of disease progression. We identified significant differences in elastin content, collagen orientation, adipocyte contents, and also a deposition of newly formed collagen forming a neoadventitia. We could discriminate two types of remodeled walls: (i) potentially safe and (ii) possibly vulnerable associated with inflammation and a high amount of adipocytes.

Clinical Validation of a Semi-Automated Software for Maximal Diameter Measurements for Endovascular Repair Follow-up

PURPOSE

To compare automated measurements of maximal diameter (D_max) of abdominal aortic aneurysm (AAA) orthogonal to luminal or outer wall envelope centerline for endovascular repair (EVAR) follow-up.

MATERIAL AND METHODS

Eighty-three consecutive patients with AAA treated by EVAR who had at least 1 computed tomography (CT) scan before and 2 CT scans after EVAR with at least 5 months' interval were included. Three-dimensional reconstruction of the AAA was achieved with dedicated segmentation software. Performances of automated calculation algorithms of D_max perpendicular to lumen or outer wall envelope centerlines were then compared to manual measurement of D_max on double-oblique multiplanar reconstruction (gold standard). Accuracy of automated D_max measurements at baseline, follow-up, and progression over time was evaluated by calculation of mean error, Bland-Altman plot, and regression models.

RESULTS

Disagreement in D_max measurements between outer wall envelope algorithm and manual method was insignificant (mean error: baseline, -0.07 ± 1.66 mm, P = .7; first follow-up, 0.24 ± 1.69 mm, P = .2; last follow-up, -0.41 ± 2.74 mm, P = .17); whereas significant discrepancies were found between the luminal algorithm and the manual method (mean error: baseline, -1.24 ± 2.01 mm, P < .01; first follow-up, -1.49 ± 3.30 mm, P < .01; last follow-up, -1.78 ± 3.60 mm, P < .01). D_max progression results were more accurate with AAA outer wall envelope algorithm compared to luminal method (P = .2).

CONCLUSIONS

AAA outer wall envelope segmentation is recommended to enable automated calculation of D_max perpendicular to its centerline during EVAR follow-up.

Surgical Outcome of Abdominal Aortic Aneurysm Replacement in Patients with Connective Tissue Disorders under 30 Years of Age

Objectives: Abdominal aortic aneurysm (AAA) in patients <30 years old is relatively rare. We retrospectively analyzed patients <30 years who received an AAA replacement.

Materials: Among 3,003 patients who received an AAA replacement during the last 40 years, 10 patients <30 years old were retrospectively reviewed. All patients suffered from a connective tissue disease: eight from Marfan syndrome and two from Loeys–Dietz syndrome. Five patients had a history of cardiovascular surgery. Aortic pathologies were a dissection type in eight patients and a non-dissection type in two. All patients received a graft replacement of infrarenal AAA, with a bifurcated graft in six patients and a straight graft in four.

Results: Except for cases that were urgent and emergent, rapid aneurysm expansion was noted in all cases. Mean AAA diameter at surgery was 46.7±9.2 mm. No hospital mortality was recorded. Eight patients required 10 additional cardiovascular surgeries: two root replacements, two total arch replacements, two descending aortic replacements, and four thoracoabdominal replacements.

Conclusion: AAA replacement in patients <30 years is safe. In younger patients with a connective tissue disease, AAA should be included in the routine medical check-up, and earlier surgical indication should be considered for its rapid expansion.

Sarcopenia predicts mortality and adverse outcomes after endovascular aneurysm repair and can be used to risk stratify patients

BACKGROUND

Endovascular aneurysm repair (EVAR) is currently the most common treatment of abdominal aortic aneurysms. Potential predictors of long-term survival after EVAR include physiologic, functional, and cognitive status, but assessments of these conditions have been difficult to standardize. Objective radiographic findings, such as skeletal muscle atrophy, or sarcopenia, may provide an additional means for selection of patients. This study investigates sarcopenia as a method to predict 1-year survival in patients undergoing EVAR.

METHODS

A single-institution retrospective review was conducted of all patients who underwent elective EVAR from September 2002 to June 2014. Patients with an available periprocedural computed tomography (CT) scan and clinical data were included in the analysis. Normalized total psoas cross-sectional area (nTPA) was measured on axial CT images using the area of the bilateral psoas muscle at the third lumbar vertebral level normalized to the square of patient height. A threshold for optimal estimate of sarcopenia based on nTPA was determined using a receiver operating characteristic curve. Sarcopenia was evaluated as an independent risk predictor using univariate, multivariate, and survival analysis.

RESULTS

A total of 272 EVAR-treated patients were evaluated, including 237 men and 35 women with a median age of 72 years and mean body mass index of 28.6 kg/m². There was a significant increase in overall mortality in patients in the lowest quartile of nTPA (Q1, 23.53%; Q2, 13.24%; Q3, 7.35%; Q4, 5.88%; P = .01). The estimated nTPA threshold for increased mortality after EVAR was 500 mm²/m². Using this threshold, sarcopenia accounted for 57% of the risk effect in our 1-year survival model.

CONCLUSIONS

Sarcopenia can assist in identifying EVAR candidates who are less likely to benefit from surgery. It can be readily evaluated from preoperative CT scans and may be a useful tool in evaluation of abdominal aortic aneurysm patients with applications in risk evaluation and telemedicine.

Normal values of aortic dimensions assessed by multidetector computed tomography in the Copenhagen General Population Study

Aims

Accurate assessment of aortic dimensions can be achieved using contrast-enhanced computed tomography. The aim of this study was to define normal values and determinants of aortic dimensions throughout multiple key anatomical landmarks of the aorta in healthy individuals from the Copenhagen General Population Study.

Methods and results

The study group consisted of 902 healthy subjects selected from 3000 adults undergoing cardiovascular thoracic and abdominal computed tomography-angiography (CTA), where systematic measurements of aortic dimensions were performed retrospectively. Individuals included were without any of the following predefined cardiovascular risk factors: (i) self-reported angina pectoris; (ii) hypertension; (iii) hypercholesterolaemia; (iv) taking cardiovascular prescribed medication including diuretics, statins, or aspirin; (v) overweight (defined as body mass index ≥30 kg/m2); (vi) diabetes mellitus (self-reported or blood glucose >8 mmol/L); and (vii) chronic obstructive pulmonary disease. Maximal aortic diameters were measured at seven aortic regions: sinuses of Valsalva, sinotubular junction, ascending aorta, mid-descending aorta, abdominal aorta at the diaphragm, abdominal aorta at the coeliac trunk, and infrarenal abdominal aorta. Median age was 52 years, and 396 (40%) were men. Men had significantly larger aortic diameters at all levels compared with women (P < 0.001). Multivariable analysis revealed that sex, age, and body surface area were associated with increasing aortic dimensions.

Conclusion

Normal values of maximal aortic dimensions at key aortic anatomical locations by contrast-enhanced CTA have been defined. Age, sex, and body surface area were significantly associated with these measures at all levels of aorta. Aortic dimensions follow an almost identical pattern throughout the vessel regardless of sex.

Contemporary imaging methods for the follow-up after endovascular abdominal aneurysm repair: a review

Abdominal aortic aneurysm (AAA) is defined as a localized enlargement of the aortic cross-section where the diameter is greater than 3 cm or more than 50% larger than the diameter in a normal segment. The most important complication of AAA is rupture, which, if untreated, results in mortality rates of up to 90%. Conventional open surgical repair is associated with significant 30-day mortality. Endovascular aneurysm repair (EVAR) is a significantly less invasive procedure; it is related to a lower early mortality rate and a lower number of perioperative complications. Although EVAR is a minimally invasive technique, lifelong follow-up imaging is necessary due to possible late complications including endoleak, recurrent aneurysm formation, graft infection, migration, kinking and thrombosis. The total rate of complications after EVAR is estimated at approximately 30%, and the rate of complications that require intervention is 2–3%. Early detection and progression analysis of such situations is crucial for proper intervention.

Pharmacologic Management of Aneurysms

Current management of aortic aneurysms relies exclusively on prophylactic operative repair of larger aneurysms. Great potential exists for successful medical therapy that halts or reduces aneurysm progression and hence alleviates or postpones the need for surgical repair. Preclinical studies in the context of abdominal aortic aneurysm identified hundreds of candidate strategies for stabilization, and data from preoperative clinical intervention studies show that interventions in the pathways of the activated inflammatory and proteolytic cascades in enlarging abdominal aortic aneurysm are feasible. Similarly, the concept of pharmaceutical aorta stabilization in Marfan syndrome is supported by a wealth of promising studies in the murine models of Marfan syndrome-related aortapathy. Although some clinical studies report successful medical stabilization of growing aortic aneurysms and aortic root stabilization in Marfan syndrome, these claims are not consistently confirmed in larger and controlled studies. Consequently, no medical therapy can be recommended for the stabilization of aortic aneurysms. The discrepancy between preclinical successes and clinical trial failures implies shortcomings in the available models of aneurysm disease and perhaps incomplete understanding of the pathological processes involved in later stages of aortic aneurysm progression. Preclinical models more reflective of human pathophysiology, identification of biomarkers to predict severity of disease progression, and improved design of clinical trials may more rapidly advance the opportunities in this important field.

An Abdominal Aortic Aneurysm, Intramural Thrombus and Moderate Leak in an Asian Man Presenting with Acute Gastroenteritis

Introduction

Missing a leaking abdominal aortic aneurysm (AAA) is common in medical practice because few at-risk patients have a history of AAA and many have an unusual presentation.

Background

AAA is less common among Asians than white Caucasians of the same age. Our patient had no significant risk factors apart from age and sex and had an unusual presentation.

Patient and Methods

A 67-year-old Asian man presented to the emergency room (ER) with a 1-day history of nausea, vomiting, diarrhoea, fever and abdominal pain. He was febrile, dehydrated. and had marked tenderness at the right iliac fossa. Laboratory findings suggested bacterial gastroenteritis but this did not explain the localized tenderness at the right iliac fossa.

Result and Discussion

A CT scan of the abdomen revealed an AAA arising above the origins of the renal arteries, an intramural thrombus, a retroperitoneal haematoma and a leak extending to the right iliac fossa. The patient was transferred to another hospital and underwent exploratory laparotomy, surgical repair of the aneurysm, and aortobi-iliac grafting with removal of the thrombus. The patient was discharged in good shape 3 weeks after surgery. Without the CT scan of the abdomen, the AAA could have been missed and the patient treated for severe gastroenteritis.

LEARNING POINTS

Giant, 20 cm Diameter, Ruptured Abdominal Aortic Aneurysm: A Case Report

Introduction

The rupture risk of abdominal aortic aneurysms (AAAs) depends primarily on their diameter and increases exponentially with aneurysm growth. Therefore, giant AAAs, defined as > 13.0 cm in diameter, are rare clinical entities.

Report

A giant ruptured AAA that measured >20 cm in diameter was successfully treated by open repair.

Conclusion

It remains unclear why giant AAAs continue to grow to extreme size without rupturing. Open repair seems to be the treatment of choice for most giant aneurysms, both ruptured and unruptured.

Is the impact of conventional risk factors the same in men and women? Plea for a more gender-specific approach

Cardiovascular disease (CVD) is the leading cause of death in women in developed countries. The traditional modifiable risk factors are able to explain the majority of CVD mortality. The aim of this review is to analyze gender-specific aspects of major conventional cardiovascular risk factors and to assess whether they have the same impact on CVD in women. Cigarette smoking remains the single largest preventable cause of cardiovascular morbidity and premature death worldwide. Women smoke less than men; however, smoking seems to be more harmful in women, particularly in oral contraceptive users. Obesity in the general population is more prevalent in women. Visceral adiposity is associated with insulin resistance and a higher risk of developing cardiovascular disease. Life expectancy in female diabetic patients is shorter than in men with diabetes; women with diabetes are also at higher risk of developing cardiovascular events. Changes of main lipid parameters in women are frequently associated with their hormonal status and/or hormonal treatment. Hypertension is highly prevalent in post-menopausal women and carries a higher risk of developing left ventricular hypertrophy, which, together with a greater increase in vascular and myocardial stiffness, results in a higher incidence of heart failure with preserved ejection fraction and a higher risk of developing stroke. The risk of abdominal aortic rupture is substantially higher in women. In conclusion, smoking, diabetes and hypertension seem to be more harmful in women. Therefore, the question is whether there should not be lower thresholds for initiating drug treatment in women with diabetes and hypertension.

Antithrombotic therapy in abdominal aortic aneurysm: beneficial or detrimental?

Abdominal aortic aneurysm (AAA) is a degenerative vascular pathology resulting in significant morbidity and mortality in older adults due to rupture and sudden death. Despite 150 000 new cases and nearly 15 000 deaths annually, the only approved treatment of AAA is surgical or endovascular intervention when the risk for aortic rupture is increased. The goal of the scientific community is to develop novel pharmaceutical treatment strategies to reduce the need for surgical intervention. Because most clinically relevant AAAs contain a complex structure of fibrin, inflammatory cells, platelets, and red blood cells in the aneurysmal sac known as an intraluminal thrombus (ILT), antithrombotic therapies have emerged as potential pharmaceutical agents for the treatment of AAA progression. However, the efficacy of these treatments has not been shown, and the effects of shrinking the ILT may be as detrimental as they are beneficial. This review discusses the prospect of anticoagulant and antiplatelet (termed collectively as antithrombotic) therapies in AAA. Herein, we discuss the role of the coagulation cascade and platelet activation in human and animal models of AAA, the composition of ILT in AAA, a possible role of the ILT in aneurysm stabilization, and the implications of antithrombotic drugs in AAA treatment.

Larger Sizes Matter More! Applying the Matteo Mathematics Method for Endovascular Aortic Bifurcation Reconstruction to Large Venous Vascular Repair

Endovascular aortobifemoral bypass repair with aortic bifurcation reconstruction is a well-established option with mortality benefits compared to conventional surgical management. The same theory, formulas, and techniques can be applied to the central venous system as long as there are commercially available devices. Using mathematically derived criteria for optimal stent size selection, endovascular aortic bifurcation reconstruction with kissing stents was extrapolated to the inferior vena cava (IVC). This report describes a traumatic case of IVC injury that was successfully repaired using the standard aortic grafts while adhering to the guidelines for proper stent size selection.

A study of outcomes in conservatively managed patients with large abdominal aortic aneurysms deemed unfit for surgical repair

BACKGROUND

The current advancement and increasing use of diagnostic imaging has led to increased detection of abdominal aortic aneurysms (AAA). Many of these patients are unfit for elective AAA surgery.

AIM

To investigate the outcome of conservative management of unfit patients with large AAA (>5.5 cm) who are turned down for elective surgical intervention.

PATIENTS AND METHODS

Between January 2006 and April 2017, 457 patients presented with AAA >5.5 cm. Seventy-six patients (M: F 54:22) were deemed unfit for elective repair. Mean age was 79.8 years (range 64-96). Mean AAA size was 60.22 mm (55-83).

RESULTS

Forty-nine of the 76 patients (64%) had died by April 2017. Fifteen (19.7%) patients died directly because of their aneurysm rupture. A further 34 (44.7%) patients died from non-aneurysm-related causes.

CONCLUSION

Patients with large AAA deemed unfit for elective surgery have an overall poor prognosis and die mainly from other causes than AAA. Surgical intervention when rupture occurs results in poor survival.

Traditional and ultrasound physical examinations: a hybrid approach to improve clinical care

Point-of-care ultrasonography, which is performed at the bedside by physicians who are not specialists in imaging, has become possible thanks to recent technological advances that have allowed for a device with greater portability while maintaining image quality. The increasing use of point-of-care ultrasonography in different specialties has made it possible to expand physical examinations, make timely decisions about the patients and allows the performance of safer medical procedures. In this review, three cases from our experience are presented that highlight the use of point-of-care ultrasonography by clinicians. Bedside ultrasonography is a convenient modality used in a clinical setting to aid in early diagnosis of several common conditions. It is suggested that a hybrid approach of physical examination and point-of-care ultrasonography in the everyday clinical practice is an inevitable change of paradigm that is improving quality of care in a variety of clinical settings.

Advances and Future Direction of Magnetic Resonance Elastography

The mechanical properties of soft tissues are closely associated with a variety of diseases. This motivates the development of elastography techniques in which tissue mechanical properties are quantitatively estimated through imaging. Magnetic resonance elastography (MRE) is a noninvasive phase-contrast MR technique wherein shear modulus of soft tissue can be spatially and temporally estimated. MRE has recently received significant attention due to its capability in noninvasively estimating tissue mechanical properties, which can offer considerable diagnostic potential. In this work, recent technology advances of MRE, its future clinical applications, and the related limitations will be discussed.

Impact of aortic aneurysms in trans-catheter aortic valve replacement: A single center experience

Background

Patients who undergo trans-catheter aortic valve replacement (TAVR) may have concomitant aortic aneurysms. We sought to clarify the incidence of aortic aneurysms and its impact on clinical outcomes among patients undergoing TAVR.

Methods

We performed a retrospective analysis of patients with severe symptomatic aortic stenosis who underwent TAVR from January 2012 to June 2016. Multi-detector computer tomography (MDCT) was performed on all patients and images were reviewed to identify thoracic and abdominal aortic aneurysms (TAA and AAA). The incidence of vascular complications (VARC-2 definition), and in-hospital and 6-month major adverse cardiac events (MACE) defined as a composite of all-cause mortality, cardiac arrest, myocardial infarction, and stroke were recorded.

Results

Among 232 patients included in the analysis, 22 patients (9.5%) had aortic aneurysms (11 had AAA, 8 had TAA, and 3 had both). Patients with aortic aneurysms had a higher, albeit statistically insignificant, rate of smoking history (63.6% vs. 42.9%, p = 0.062). Both groups of patient predominantly underwent TAVR via trans-femoral access (72.7% vs. 71.4%, p = 0.90). The incidence of vascular complications was similar between the two groups (9.1% vs. 10.5%, p = 1.0). Patients with aortic aneurysms had a similar in-hospital MACE (4.5% vs. 6.2%, p = 1.0) and 6-month MACE (9.1% vs. 9.0%, p = 1.0) compared to those without aneurysms.

Conclusions

In our patient cohort, 9.5% of patients who underwent TAVR had concomitant aortic aneurysms. Patients with aortic aneurysms had similar incidence of vascular complications as well as in-hospital and 6-month MACE compared to those without.

Patients with end-stage renal disease have poor outcomes after endovascular abdominal aortic aneurysm repair

OBJECTIVE

Although endovascular repair of abdominal aortic aneurysms (AAAs) has been demonstrated to have favorable outcomes, not all cohorts of patients with AAA fare equally well. Our goal was to investigate perioperative and 1-year outcomes in patients with end-stage renal disease (ESRD) on dialysis, who have traditionally fared worse after vascular interventions, to assess how ESRD affects outcomes in a large modern cohort of endovascular aneurysm repair (EVAR) patients.

METHODS

The Vascular Quality Initiative database was queried for all patients undergoing EVAR from 2010 to 2017. ESRD patients were compared with patients not on dialysis. Propensity-matched scoring and multivariable analysis were used to isolate the effects of ESRD.

RESULTS

Of 28,683 EVARs identified, there were 321 (1.12%) patients with ESRD on dialysis. Patients with ESRD had no difference in presenting AAA size (57.5 ± 12.7 mm vs 56.7 ± 17.2 mm; P = .44); however, they had more urgent/emergent repairs (20.6% vs 13.6%; P = .002) than those without ESRD. ESRD patients were more often younger, nonwhite, and nonobese and less likely to have commercial insurance (P < .05). ESRD patients more often had hypertension, coronary artery disease, congestive heart failure, previous lower extremity bypass, aneurysm repair, and carotid interventions (P < .05). There was no difference in the rate of concomitant procedures. Matching based on demographics, comorbidities, and operative details showed that ESRD patients had longer hospital length of stay (4.8 ± 9.4 days vs 4.1 ± 12.6 days; P = .026) and higher 30-day mortality (7% vs 2.4%; P < .001). There was no difference in cardiac, pulmonary, lower extremity, bowel, and stroke complications or return to the operating room. On multivariable analysis, ESRD was associated with 30-day mortality (odds ratio, 4.1; 95% confidence interval, 2.6-6.7; P < .001). Of the 24,750 elective EVARs, 1.04% had ESRD on dialysis. Matched data for elective EVAR show increased postoperative length of stay, hospital mortality, and 30-day mortality for ESRD patients on dialysis compared with those who are not. There was no association with postoperative myocardial infarction or pulmonary complications. At 1 year, patients with ESRD on dialysis had worse survival (78% vs 94%; P < .001), and ESRD was associated with higher mortality (hazard ratio, 3.3; 95% confidence interval, 2.5-4.2; P < .001).

CONCLUSIONS

Among patients undergoing EVAR, ESRD is independently associated with higher perioperative and 1-year mortality despite not being associated with higher postoperative complications. This should be taken into account during informed consent for EVAR and risk-benefit considerations in this high-risk population, particularly for elective repair.

Direct health costs and clinical outcomes of open surgery in patients with abdominal aortic aneurysm in Spain. The RECAPTA study

OBJECTIVE

Abdominal aortic aneurysm (AAA) is a chronic, progressive disease that often requires surgical repair. This study aimed to assess the healthcare costs and clinical outcomes of open AAA repair in Spain.

METHOD

Observational, retrospective, multicenter study with a one-year follow-up. Healthcare resource use and costs related to the surgical procedure, hospital stay, and follow-up period were assessed.

RESULTS

Ninety patients with asymptomatic AAA who underwent open repair were recruited between 2003 and 2009 at three Spanish hospitals. Four patients (4.44%) died in the first 30 postoperative days. Mean [standard deviation] procedure time was 292.83 [72.10] minutes and mean hospital length of stay was 11.44 days [5.42]. Thirty two patients (35.56%) presented in-hospital complications and three patients (3.45%) underwent re-intervention during follow-up. The mean overall cost per patient during the study period was €21,622.59, of which 42.40% (€9,168.19), 52.08% (€11,261.74), and 5.52% (€1,192.66) corresponded to the surgical procedure, the inpatient stay, and the study follow-up period, respectively.

CONCLUSIONS

Given the economic burden imposed by the treatment of patients admitted with AAA on the Spanish health system, additional efforts comparing the cost of open repair with endovascular treatments are needed to ensure greater efficiency.

Combined Aorto-Iliac and Anterior Lumbar Spine Reconstruction: A Case Series

BACKGROUND

Treatment options for aortic-iliac pathology may include endovascular repair and open surgical repair. Treatment options for degenerative disc disease (DDD) are varied but commonly include anterior reconstruction. When both the aortic-iliac and spinal pathologies are significant and surgical intervention is indicated for each pathology, the opportunity exists for concurrent treatment of both the aortic-iliac pathology and DDD in the same operation. The purpose of this case series was to document the safety and feasibility of a surgical strategy whereby a combined elective reconstructive procedure was performed for aortic and anterior lumbar spinal pathologies.

METHODS

The case histories of 5 patients who were treated for both spinal and vascular pathology are presented. Surgical outcome measures included operative time, blood loss, length of stay, and complications. Spine-specific outcome measures included Oswestry Disability Index, Roland Morris Disability Questionnaire, and visual analogue scores (back and leg).

RESULTS

The spinal reconstructions performed included 1 L4-5 total disc replacement (TDR), 1 L4-5, L5-S1 anterior lumbar interbody fusion (ALIF), 1 L5-S1 ALIF, and 2 hybrid procedures (L4-5 TDR with L5-S1 ALIF). Vascular reconstructions included 4 aorto-bi-iliac bypass grafts and 1 aortic tube graft. The average operative time was 365 minutes (ranging between 330 and 510 minutes), the average blood loss was 1699 mL (range between 1160 and 2960 mL), and the average length of hospital stay was 14 days (range from 8 to 22 days). There were no in-hospital complications, and all patients experienced significant improvement in both back and leg pain. One patient developed kinking of the iliac limbs of the vascular graft 1 year postoperatively, which was managed with endovascular stenting of the graft.

CONCLUSIONS

Aortic-iliac pathology and DDD are significant pathologies often treated in isolation. This study illustrates that, despite its complexity, highly trained individuals in a specialized setting can perform combined surgery to achieve a satisfactory outcome for the patient.

LEVEL OF EVIDENCE

Level IV evidence.

Abdominal Aortic Aneurysm: Evolving Controversies and Uncertainties

Abdominal aortic aneurysm (AAA) is defined as a permanent dilatation of the abdominal aorta that exceeds 3 cm. Most AAAs arise in the portion of abdominal aorta distal to the renal arteries and are defined as infrarenal. Most AAAs are totally asymptomatic until catastrophic rupture. The strongest predictor of AAA rupture is the diameter. Surgery is indicated to prevent rupture when the risk of rupture exceeds the risk of surgery. In this review, we aim to analyze this disease comprehensively, starting from an epidemiological perspective, exploring etiology and pathophysiology, and concluding with surgical controversies. We will pursue these goals by addressing eight specific questions regarding AAA: (1) Is the incidence of AAA increasing? (2) Are ultrasound screening programs for AAA effective? (3) What causes AAA: Genes versus environment? (4) Animal models: Are they really relevant? (5) What pathophysiology leads to AAA? (6) Indications for AAA surgery: Are surgeons over-eager to operate? (7) Elective AAA repair: Open or endovascular? (8) Emergency AAA repair: Open or endovascular?

Current status of the treatment of infrarenal abdominal aortic aneurysms

Aortic aneurysms are the 13^th leading cause of death in the United States. While aneurysms can occur along the entire length of the aorta, the infrarenal location is the most common. Targeted ultrasound screening has been found to be an effective and economical means of preventing aortic aneurysm rupture. The indication for repair includes either symptomatic aneurysms or aneurysms with a diameter greater than 5.4 cm. Treatment options for the repair of infrarenal aortic aneurysms are open surgical repair (OSR) and endovascular aneurysm repair (EVAR). Currently, EVAR is the primary treatment method for the repair of infrarenal aortic aneurysms due to improved short-term morbidity and mortality outcomes. This article is intended to review the current status of the management of infrarenal abdominal aortic aneurysms (AAA).

Astragaloside IV Attenuated 3,4-Benzopyrene-Induced Abdominal Aortic Aneurysm by Ameliorating Macrophage-Mediated Inflammation

Abdominal aortic aneurysm (AAA), characterized by macrophage infiltration-mediated inflammation and oxidative stress, is a potentially fatal disease. Astragaloside IV (AS-IV) has been acknowledged to exhibit antioxidant and anti-inflammatory properties. This study was designed to investigate the protective effect of AS-IV against AAA formation induced by 3,4-benzopyrene (Bap) and angiotensin II (Ang II), and to explore probable mechanisms. Results showed that AS-IV decreased AAA formation, and reduced macrophage infiltration and expression of matrix metalloproteinase. Furthermore, AS-IV abrogated Bap-/Ang II-induced NF-κB activation and oxidative stress. In vitro, AS-IV inhibition of macrophage activation and NF-κB was correlated with increased phosphorylation of phosphatidylinositol 3-kinase (PI3-K)/AKT. Together, our findings suggest that AS-IV has potential as an intervention in the formation of AAA.

Patient satisfaction with the consent discussion is not improved by showing patients their computed tomography or angiography images before they undergo vascular surgery

OBJECTIVE

Patient-based decision aids and other multimedia tools have been developed to help enrich the preoperative discussion between surgeon and patient. Use of these tools, however, can be time-consuming and logistically challenging. We investigated whether simply showing patients their images from preoperative computed tomography (CT) or angiography would improve patients' satisfaction with the preoperative discussion. We also examined whether this improved the patient's understanding and trust and whether it contributed to increased preoperative anxiety.

METHODS

Patients undergoing either elective abdominal aortic aneurysm repair or lower limb revascularization were randomly assigned to either standard perioperative discussion or perioperative discussion and review of images (CT image or angiogram). Randomization was concealed and stratified by surgeon. Primary outcome was patient satisfaction with the preoperative discussion as measured by a validated 7-item scale (score, 0-28), with higher scores indicating improved satisfaction. Secondary outcomes included patient understanding, patient anxiety, patient trust, and length of preoperative discussion. Scores were compared using t-test.

RESULTS

Overall, 51 patients were randomized, 25 to the intervention arm (discussion and imaging) and 26 to the control arm. Most patients were male (69%), and the average age was 70 years. Forty percent of patients underwent abdominal aortic aneurysm repair, whereas 60% underwent lower limb revascularization. Patient satisfaction with the discussion was generally high, with no added improvement when preoperative images were reviewed (mean score, 24.9 ± 3.02 vs 24.8 ± 2.93; P = .88). Similarly, there was no difference in the patient's anxiety, level of trust, or understanding when the imaging review was compared with standard discussion. There was a trend toward longer preoperative discussions in the group that underwent imaging review (8.18 vs 6.35 minutes; P = .07).

CONCLUSIONS

Showing patients their CT or angiography images during the preoperative discussion does not improve the patient's satisfaction with the consent discussion. Similarly, there was no effect on the patient's trust, understanding, or anxiety level. Our conclusions are limited by the lack of a standardized measure of patient understanding and not measuring outcomes postoperatively, both of which should be considered in future studies.

[Identifying barriers to screening for abdominal aortic aneurysm in general practice: Qualitative study of 14 general practitioners in Paris]

INTRODUCTION

Abdominal aortic aneurysm (AAA) is a silent pathology with often fatal consequences in case of rupture. AAA screening, recommended in France and many other countries, has shown its effectiveness in reducing specific mortality. However, AAA screening rate remains insufficient.

OBJECTIVE

To identify barriers to AAA screening in general practice.

MATERIAL AND METHOD

Qualitative study carried out during 2016 among general practitioners based in Paris.

RESULTS

Fourteen physicians were included. Most of the barriers were related to the physician: unawareness about AAA and screening recommendations, considering AAA as a secondary question not discussed with the patient, abdominal aorta not included in cardiovascular assessment, no search for a familial history of AAA, AAA considered a question for the specialist, lack of time, lack of training, numerous screenings to propose, oversight. Some barriers are related to the patient: unawareness of the pathology and family history of AAA, refusal, questioning the pertinence of the doctor's comments, failure to respect the care pathway. Others are related to AAA: source of anxiety, low prevalence, rarity of complications. The remaining barriers are related to screening: cost-benefit and risk-benefit ratios, sonographer unavailability, constraint for the patient, overmedicalization.

CONCLUSION

Information and training of general practitioners about AAA must be strengthened in order to optimize AAA screening and reduce specific mortality.

Epidemiology and contemporary management of abdominal aortic aneurysms

Abdominal aortic aneurysm (AAA) is most commonly defined as a maximal diameter of the abdominal aorta in excess of 3 cm in either anterior-posterior or transverse planes or, alternatively, as a focal dilation ≥ 1.5 times the diameter of the normal adjacent arterial segment. Risk factors for the development of AAA include age > 60, tobacco use, male gender, Caucasian race, and family history of AAA. Aneurysm growth and rupture risk appear to be associated with persistent tobacco use, female gender, and chronic pulmonary disease. The majority of AAAs are asymptomatic and detected incidentally on various imaging studies, including abdominal ultrasound, and computed tomographic angiography. Symptoms associated with AAA may include abdominal or back pain, thromboembolization, atheroembolization, aortic rupture, or development of an arteriovenous or aortoenteric fistula. The Screening Abdominal Aortic Aneurysms Efficiently (SAAAVE) Act provides coverage for a one-time screening abdominal ultrasound at age 65 for men who have smoked at least 100 cigarettes and women who have family history of AAA disease. Medical management is recommended for asymptomatic patients with AAAs < 5 cm in diameter and focuses on modifiable risk factors, including smoking cessation and blood pressure control. Primary indications for intervention in patients with AAA include development of symptoms, rupture, rapid aneurysm growth (> 5 mm/6 months), or presence of a fusiform aneurysm with maximum diameter of 5.5 cm or greater. Intervention for AAA includes conventional open surgical repair and endovascular aortic stent graft repair.

Endothelium as a Potential Target for Treatment of Abdominal Aortic Aneurysm

Abdominal aortic aneurysm (AAA) was previously ascribed to weaken defective medial arterial/adventitial layers, for example, smooth muscle/fibroblast cells. Therefore, besides surgical repair, medications targeting the medial layer to strengthen the aortic wall are the most feasible treatment strategy for AAA. However, so far, it is unclear whether such drugs have any beneficial effect on AAA prognosis, rate of aneurysm growth, rupture, or survival. Notably, clinical studies have shown that AAA is highly associated with endothelial dysfunction in the aged population. Additionally, animal models of endothelial dysfunction and endothelial nitric oxide synthase (eNOS) uncoupling had a very high rate of AAA formation, indicating there is crucial involvement of the endothelium and a possible pharmacological solution targeting the endothelium in AAA treatment. Endothelial cells have been found to trigger vascular wall remodeling by releasing proteases, or recruiting macrophages along with other neutrophils, into the medial layer. Moreover, inflammation and oxidative stress of the arterial wall were induced by endothelial dysfunction. Interestingly, there is a paradoxical differential correlation between diabetes and aneurysm formation in retinal capillaries and the aorta. Deciphering the significance of such a difference may explain current unsuccessful AAA medications and offer a solution to this treatment challenge. It is now believed that AAA and atherosclerosis are two separate but related diseases, based on their different clinical patterns which have further complicated the puzzle. Therefore, a thorough investigation of the interaction between endothelium and medial/adventitial layer may provide us a better understanding and new perspective on AAA formation, especially after taking into account the importance of endothelium in the development of AAA. Moreover, a novel medication strategy replacing the currently used, but suboptimal treatments for AAA, could be informed with this analysis.

Type II endoleaks: diagnosis and treatment algorithm

Elective abdominal aortic aneurysm (AAA) repair is recommended for aneurysms greater than 5.5 cm, symptomatic, or rapidly expanding more than 0.5 cm in 6 months. Seventy-five percent of AAAs today are treated with endovascular aneurysm repair (EVAR) rather than open repair. This is fostered by the lower periprocedural mortality, complications, and length of hospital stay associated with EVAR. However, some studies have demonstrated EVAR to result in higher reintervention rates than with open repair, largely due to endoleaks. Type II is the most common, making up 10-25% of all endoleaks. Type II endoleaks, can potentially enlarge and pressurize the aneurysm sac with a risk of rupture. However, many type II endoleaks spontaneously resolve or never lead to sac enlargement. Imaging surveillance and approaches to management of type II endoleaks are reviewed here.

Necroptosis in cardiovascular disease - a new therapeutic target

Contrary to the apoptosis-necrosis binary view of cell death, recent experimental evidence demonstrates that several forms of necrosis, represented by necroptosis, are regulated or programmed in nature. Multiple death stimuli known to be associated with cardiovascular disease are capable of causing either apoptosis or necroptosis. Whether a cell dies from apoptosis or necroptosis has distinct consequences on inflammation. It is known that apoptosis, a non-lytic form of death mediated by the caspase family of proteases, does not generally evoke an immune response. Necroptosis, on the other hand, is a lytic form of cell death. Due to the rapid loss of plasma membrane integrity, cells dying from necroptosis release proinflammatory intracellular contents and subsequently cause inflammation. Our review delineates various genetic and biochemical evidence that demonstrates a compelling role of necroptosis in the pathogenesis and/or progression of cardiovascular disease including myocardial infarction, atherosclerosis, and aortic aneurysm. Through recent studies of necroptosis in cardiovascular diseases, we attempt to discuss the role of necroptosis in vascular inflammation as well as the potential of necroptosis inhibitors in future clinical management of cardiovascular events. Inhibiting necroptosis in the vasculature has an overall protective role and necroptosis may represent a new therapeutic target to prevent the development and progression of cardiovascular diseases.

Single-center experience with complex abdominal aortic aneurysms treated by open or endovascular repair using fenestrated/branched endografts

OBJECTIVE

The objective of this study was to evaluate outcomes of patients with complex abdominal aortic aneurysms (cAAAs) treated with open repair (OR) or fenestrated/branched endovascular aneurysm repair (F/B-EVAR) from a single center.

METHODS

A retrospective analysis of consecutive patients with cAAAs treated electively by OR or F/B-EVAR between January 2010 and February 2017 was conducted. Demographics of the patients, cardiovascular risk factors, procedure time, number of vessels incorporated, radiation dose, estimated blood loss, intensive care unit (ICU) length of stay (LOS), and hospital LOS were recorded. End points included target vessel patency, aneurysm rupture, freedom from reintervention, and major adverse events (MAEs).

RESULTS

During this period, 153 patients (OR, 69; F/B-EVAR, 84) underwent repair of cAAA. The majority were male (OR, 55; F/B-EVAR, 64), with a mean age of 75.8 ± 7.6 years (F/B-EVAR) and 71.2 ± 7.9 years (OR). Patients in the F/B-EVAR group were more likely to be American Society of Anesthesiologists class 3 and 4 (60% vs 0%; P < .001) and had a higher median Society for Vascular Surgery/American Association for Vascular Surgery comorbidity severity score (15 vs 7; P < .001). A total of 235 vessels were targeted in the F/B-EVAR group, with a technical success of 97.6%. Thirty-one patients in the OR group required concomitant renal artery revascularization. Transfusion requirements (100% vs 1.2%), MAEs (40.6% vs 13.1%), procedure length (304 minutes vs 140 minutes), estimated blood loss (2246 mL vs 165 mL), ICU LOS (3 days vs 1 day), and hospital LOS (7 days vs 2 days) were higher (P < .001) in the OR group compared with the F/B-EVAR group. The 30-day mortality was 2.9% and 2.4% (P = .84) in the OR group and F/B-EVAR group, respectively. Supraceliac clamp site was associated with increased incidence of postoperative renal insufficiency. A decrease in procedure time, contrast volume, fluoroscopy time, and fluoroscopy dose was noted in the F/B-EVAR group with increasing experience even as case complexity increased. More patients were discharged home after F/B-EVAR (97.6% vs 59.4%; P < .001). With a mean follow-up of 31 months (F/B-EVAR, 17 months; OR, 48 months), the rate of secondary intervention was 3.7% and 5.8% (P = NS) for F/B-EVAR and OR, respectively. Freedom from branch instability and reintervention was 99% (95% confidence interval, 96.2%-99.8%) and 96% (95% confidence interval, 87.1%-98.6%), respectively.

CONCLUSIONS

Results of this "real-world" experience suggest that the use of F/B-EVAR for the treatment of cAAAs in high-risk surgical patients is safe and effective and has comparable short-term results to those of low-risk patients undergoing OR. Patients treated by F/B-EVAR had shorter ICU and hospital LOS, lower MAEs, and faster convalescence. A decrease in procedure time and radiation dose was noted as experience was gained, even as complexity increased.

Screening key genes for abdominal aortic aneurysm based on gene expression omnibus dataset

Background

Abdominal aortic aneurysm (AAA) is a common cardiovascular system disease with high mortality. The aim of this study was to identify potential genes for diagnosis and therapy in AAA.

Methods

We searched and downloaded mRNA expression data from the Gene Expression Omnibus (GEO) database to identify differentially expressed genes (DEGs) from AAA and normal individuals. Then, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis, transcriptional factors (TFs) network and protein-protein interaction (PPI) network were used to explore the function of genes. Additionally, immunohistochemical (IHC) staining was used to validate the expression of identified genes. Finally, the diagnostic value of identified genes was accessed by receiver operating characteristic (ROC) analysis in GEO database.

Results

A total of 1199 DEGs (188 up-regulated and 1011 down-regulated) were identified between AAA and normal individual. KEGG pathway analysis displayed that vascular smooth muscle contraction and pathways in cancer were significantly enriched signal pathway. The top 10 up-regulated and top 10 down-regulated DEGs were used to construct TFs and PPI networks. Some genes with high degrees such as NELL2, CCR7, MGAM, HBB, CSNK2A2, ZBTB16 and FOXO1 were identified to be related to AAA. The consequences of IHC staining showed that CCR7 and PDGFA were up-regulated in tissue samples of AAA. ROC analysis showed that NELL2, CCR7, MGAM, HBB, CSNK2A2, ZBTB16, FOXO1 and PDGFA had the potential diagnostic value for AAA.

Conclusions

The identified genes including NELL2, CCR7, MGAM, HBB, CSNK2A2, ZBTB16, FOXO1 and PDGFA might be involved in the pathology of AAA.

MicroRNAs as possible biomarkers for screening of aortic aneurysms: a systematic review and validation study

CONTEXT

There is an urgent need to identify non-invasive biomarkers for the early detection of aortic aneurysms, preceding a fatal event. The potential role for MicroRNAs (miRNAs) as diagnostic markers for aortic aneurysms was investigated through the present systematic review.

OBJECTIVE

To perform a comprehensive review on published studies examining the association of miRNAs with aortic aneurysms and further validate these results with plasma samples collected from thoracic aortic aneurysm (TAA) patients.

METHODS

The literature search was performed via numerous databases and articles were only included if they fulfilled the predefined eligibility criteria. The miRNAs reported three times or more with expression consistency were validated using plasma samples from TAA patients collected before and following surgery.

RESULTS

Twenty-four articles were selected from the literature search and 11 miRNAs were chosen for validation using our samples. The miRNAs which were further validated were found to follow the trend in the regulation pattern as with the majority of the published data. MiRNA hsa-miR-193a-5p was found to be significantly down-regulated in the plasma samples collected before the aneurysmal removal when compared with postsurgical serum samples.

CONCLUSIONS

Numerous miRNAs have been associated with aortic aneurysms, and specifically hsa-miR-193a-5p and hsa-miR-30b-5p; therefore they warrant further investigation as potential biomarkers. Registration: The protocol of the review was registered in Prospero Databases (ID: CRD42016039953).

Hostility of proximal aortic neck anatomy in relation to abdominal aortic aneurysm size and its impact on the outcome of endovascular repair with the new generation endografts

BACKGROUND

To assess the relation of abdominal aortic aneurysm (AAA) diameter with the proximal neck anatomy (PNA) hostility and to evaluate its impact on the endovascular aneurysm repair (EVAR) outcomes with the use of newer generation endografts.

METHODS

Retrospective analysis of single institution's recorded data from February 2009 to April 2016. Patients' characteristics, comorbidities, aortic morphology, perioperative characteristics and outcomes were analyzed. In relation to AAA diameter 2 groups were identified: group A (50-55 mm) and group B (>55 mm). Hostile PNA was defined based on: neck diameter >28 mm, length <15 mm, angulation >60o, and circumferential thrombus and/or calcification >50%. The aortic neck scoring system was calculated. Multiple logistic regression analysis with a forward likelihood ratio method adjusted for age and gender was undertaken.

RESULTS

Three hundred seventeen patients (96% males, mean age 72.4±9 years, 80% elective) were follow-up for a mean of 23.4 months (range, 3-86 months). No differences were observed in demographics and co-morbidities between the two groups (group A: 134, 42% vs. group B: 183, 58%). Hostile PNA was present in 147/317 (46%) patients and significantly more likely to be present in group B (P<0.001). In group B the aortic neck score was higher (P<0.001), the likelihood for having hostile PNA increased for neck diameter by 2.2-fold (OR 2.2, P=0.013, 95% CI: 1.18-4.03), length by 2.3-fold (OR 2.3, P=0.012, 95% CI: 1.20-4.51), angle by 4.8-fold (OR 4.8, P=0.002, 95% CI: 1.79-13.24) and presence of thrombus by 1.5-fold (OR 1.5, P=0.037, 95% CI: 1.45-10.34). No association existed for neck calcification (P=0.071). Technical success, adjunctive procedures, perioperative characteristics and outcomes were comparable in friendly and hostile PNAs.

CONCLUSIONS

PNA hostility is more likely in AAA with diameter >55 mm but with the use of newer generation endografts this did not influence the short- and mid-term EVAR outcomes. Longer follow-up is needed for a more definite conclusion.