MR Elastography of Abdominal Aortic Aneurysms: Relationship to Aneurysm Events.

Background Abdominal aortic aneurysm (AAA) diameter remains the standard clinical parameter to predict growth and rupture. Studies suggest that using solely AAA diameter for risk stratification is insufficient. Purpose To evaluate the use of aortic MR elastography (MRE)-derived AAA stiffness and stiffness ratio at baseline to identify the potential for future aneurysm rupture or need for surgical repair. Materials and Methods Between August 2013 and March 2019, 72 participants with AAA and 56 healthy participants were enrolled in this prospective study. MRE examinations were performed to estimate AAA stiffness and the stiffness ratio between AAA and its adjacent remote normal aorta. Two Cox proportional hazards models were used to assess AAA stiffness and stiffness ratio for predicting aneurysmal events (subsequent repair, rupture, or diameter >5.0 cm). Log-rank tests were performed to determine a critical stiffness ratio suggesting high-risk AAAs. Baseline AAA stiffness and stiffness ratio were studied using Wilcoxon rank-sum tests between participants with and without aneurysmal events. Spearman correlation was used to investigate the relationship between stiffness and other potential imaging markers. Results Seventy-two participants with AAA (mean age, 71 years ± 9 [SD]; 56 men and 16 women) and 56 healthy participants (mean age, 42 years ± 16; 27 men and 29 women) were evaluated. In healthy participants, aortic stiffness positively correlated with age (ρ = 0.44; P < .001). AAA stiffness (event group [n = 21], 50.3 kPa ± 26.5 [SD]; no-event group [n = 21], 86.9 kPa ± 52.6; P = .01) and the stiffness ratio (event group, 0.7 ± 0.4; no-event group, 2.0 ± 1.4; P < .001) were lower in the event group than the no-event group at a mean follow-up of 449 days. AAA stiffness did not correlate with diameter in the event group (ρ = -0.06; P = .68) or the no-event group (ρ = -0.13; P = .32). AAA stiffness was inversely correlated with intraluminal thrombus area (ρ = -0.50; P = .01). Conclusion Lower abdominal aortic aneurysm stiffness and stiffness ratio measured with use of MR elastography was associated with aneurysmal events at a 15-month follow-up. © RSNA, 2022 See also the editorial by Sakuma in this issue.

Acute Aortocaval Fistula Secondary to Chronic Type 1 B Abdominal Aortic Aneurysm Endoleak.

Aortocaval fistula (ACF) is a rare complication of abdominal aortic aneurysms (AAA), involving less than 1% of all AAA and is associated with high morbidity and mortality; it is even more uncommon, following endovascular aneurysm repair. The clinical presentation can be variable and making the diagnosis can be difficult. It can present with symptoms and signs of an abdominal emergency or systemic hypoperfusion. The traditional method of repair has been open surgery, which is associated with a high mortality rate. Endovascular repair has become more common, but results are difficult to interpret due to the low incidence of ACF. A high index of suspicion is imperative to avoid delay in diagnosis and care.

Variability in Noninvasive Vascular Laboratory Experience of Vascular Surgery Training Programs Based on Survey of Trainees Suggests the Need for a Standardized Curriculum.

BACKGROUND: Although a Registered Physician in Vascular Interpretation certification is required for vascular surgery board certification, no standardized noninvasive vascular laboratory (NIVL) curriculum for vascular surgery trainees exists. The purpose of this study is to investigate the NIVL experience of trainees and understand what helps them feel well prepared. METHODS: Current trainees in all 0 + 5 and 5 + 2 vascular surgery training programs (114) were surveyed. The most complete survey from each program was included in the analysis. Programs were divided into those in which trainees felt well prepared (WP) and those in which trainees felt unprepared (UP) for the Physician Vascular Interpretation (PVI) examination. Responses for the 2 groups were compared. RESULTS: Responses from 61 of the 114 programs (53.5%) were analyzed. Most programs devote <0.5 days per week to the NIVL (52.5%), assign lectures and textbook reading (55.7% and 47.5%), and provide hands-on experience with vascular technologists (60.7%) and attending surgeons (52.5%). Respondents from 15 programs (24.6%) took a PVI examination review course. The first-time PVI examination pass rate was 92.9% (13 of 14 trainees). The WP group reported higher rates of a structured curriculum for the NIVL (100% vs. 33.3%, P = 0.0001), one-on-one time with vascular technologists (78.6% vs. 44.4%, P = 0.05), mandatory lectures (78.6% vs. 33.3%, P = 0.004), and assigned articles (64.3% vs. 11.1%, P = 0.002). CONCLUSIONS: There is wide variation in NIVL experience among vascular surgery training programs. Many trainees feel unprepared for the PVI examination, especially those without a structured curriculum. These results suggest that a structured NIVL curriculum that includes dedicated time with vascular technologists, lectures, and articles should be established.

Ultrasound-Guided Thrombin Injection Is a Safe and Effective Treatment for Femoral Artery Pseudoaneurysm in the Morbidly Obese.

INTRODUCTION: Ultrasound-guided thrombin injection (UGTI) is a well-established practice for the treatment of femoral artery pseudoaneurysm. This procedure is highly successful but dependent on appropriate pseudoaneurysm anatomy and adequate ultrasound visualization. Morbid obesity can present a significant technical challenge due to increased groin adiposity, resulting in poor visualization of critical structures needed to safely perform the procedure. We aim to evaluate the safety and efficacy of UGTI to treat femoral artery pseudoaneurysm in the morbidly obese. METHODS: This is a retrospective cohort study in which all patients who underwent UGTI at The Ohio State University Ross Heart Hospital from 2009 to 2014 were analyzed for patient characteristics and stratified by body mass index (BMI). Patients with BMI ≥ 35 were considered morbidly obese and were compared to patients with a BMI < 35. Outcome was failed treatment resulting in residual pseudoaneurysm. RESULTS: Our cohort consisted of 54 patients who underwent thrombin injection. There were 41 nonmorbidly obese and 13 morbidly obese patients. Mean age was 64.5 years. The cohort was 44.4% male. There were 6 failures, of which 1 underwent successful repeat injection and 5 underwent open surgical repair. There was no statistically significant difference in failure between nonmorbidly obese and morbidly obese patients (9.8% vs 15.4%, P = .45). There were no embolic/thrombotic complications. CONCLUSION: Ultrasound-guided thrombin injection is a safe and effective therapy in the morbidly obese for the treatment of femoral artery pseudoaneurysm. In the hands of experienced sonographers and surgeons with adequate visualization of the pseudoaneurysm sac, UGTI should remain a standard therapy in the morbidly obese.

Preoperative antiplatelet use does not increase incidence of bleeding after major operations.

BACKGROUND: This study examined the outcomes of patients holding or continuing clopidogrel during the preoperative period. METHODS: We reviewed all patients taking clopidogrel who underwent one of 72 different Current Procedural Terminology code procedures, representing major emergency and elective general thoracic and vascular operations from 2009-2012 at a single institution. Demographics, comorbidities, aspirin use, details of coronary stents, and perioperative events were collected. RESULTS: A total of 2,154 major operative procedures were performed on 1,851 patients during the study period. A total of 213 patients (11.5%) were taking clopidogrel at the time of their last office visit or hospital admission and were then instructed to hold or continue the drug prior to an operation. A total of 205 procedures in 200 patients comprised the final study population. Clopidogrel was held in 116 procedures for ≥5 days prior to operative intervention (56.6%, Group A), and clopidogrel was administered within 5 days of an operation in 89 procedures (43.4%, Group B). There were no differences between the 2 groups regarding estimated blood loss, units transfused, myocardial infarction, stroke, acute visceral or peripheral ischemia, or death within 30 days. CONCLUSION: We did not identify significantly increased adverse patient outcomes in those patients who received preoperative clopidogrel within this population. We assert that it appears to be reasonable and safe to continue antiplatelet therapy with clopidogrel in this population in elective situations and that preoperative clopidogrel use does not increase the risk of bleeding in emergency circumstances.

Quantification of abdominal aortic aneurysm stiffness using magnetic resonance elastography and its comparison to aneurysm diameter.

OBJECTIVE: Abdominal aortic aneurysm (AAA) wall stiffness has been suggested to be an important factor in the overall rupture risk assessment compared with anatomic measure. We hypothesize that AAA diameter will have no correlation to AAA wall stiffness. The aim of this study is to (1) determine magnetic resonance elastography (MRE)-derived aortic wall stiffness in AAA patients and its correlation to AAA diameter; (2) determine the correlation between AAA stiffness and amount of thrombus and calcium; and (3) compare the AAA stiffness measurements against age-matched healthy individuals. METHODS: In vivo abdominal aortic MRE was performed on 36 individuals (24 patients with AAA measuring 3-10 cm and 12 healthy volunteers), aged 36 to 78 years, after obtaining written informed consent under the approval of the Institutional Review Board. MRE images were processed to obtain spatial stiffness maps of the aorta. AAA diameter, amount of thrombus, and calcium score were reported by experienced interventional radiologists. Spearman correlation, Wilcoxon signed rank test, and Mann-Whitney test were performed to determine the correlation between AAA stiffness and diameter and to determine the significant difference in stiffness measurements between AAA patients and healthy individuals. RESULTS: No significant correlation (P > .1) was found between AAA stiffness and diameter or amount of thrombus or calcium score. AAA stiffness (mean 13.97 ± 4.2 kPa) is significantly (P ≤ .02) higher than remote normal aorta in AAA (mean 8.87 ± 2.2 kPa) patients and in normal individuals (mean 7.1 ± 1.9 kPa). CONCLUSIONS: Our results suggest that AAA wall stiffness may provide additional information independent of AAA diameter, which may contribute to our understanding of AAA pathophysiology, biomechanics, and risk for rupture.

Can the Anesthesiologist Use the Radial Artery for Monitoring After Transradial Artery Catheterization?

The use of transradial coronary angiography and intervention is growing because of its advantages over the femoral approach. However, the small size of the radial artery can contribute to complications. We present a case of an in situ access complication of transradial coronary artery catheterization. It is important for the anesthesiologist to know about the short-term and long-term consequences of this intervention, which could lead to narrowing of the artery even beyond the site of puncture. Understanding these changes could help anesthesiologists make better decisions about using the radial artery for monitoring after transradial coronary artery catheterization procedures.

Essentials of negotiating for employment in a changing environment.

Evolving changes in health care in the United States are causing new graduates and self-employed physicians to consider employment with large groups and health systems. Familiarity with the principles, proper conduct, and mechanics of negotiating an employment agreement will be important for vascular surgeons making such a decision. The various components of compensation packages and contract language need to be critically evaluated. To facilitate an understanding of the complexities involved in employment contracts, strategies to avoid making negotiating mistakes are discussed.

The EPIC nitinol stent system in the treatment of iliac artery lesions: one-year results from the ORION clinical trial.

PURPOSE: To report the 1-year results of a pivotal study for a new-generation nitinol stent for the treatment of iliac atherosclerotic lesions. METHODS: The ORION trial (ClinicalTrials.gov identifier NCT00896337) was a single-arm, non-randomized, prospective, multicenter clinical trial that enrolled 125 patients (81 men; mean age 61.1±9.3 years) implanted with the EPIC self-expanding nitinol stent system in 166 de novo or restenotic iliac artery lesions ≤13 cm long. The primary endpoint was the 9-month major adverse event rate [i.e., device- or procedure-related death within 30 days, myocardial infarction during the index hospitalization, target vessel revascularization (TVR), or index limb amputation]. Follow-up occurred at hospital discharge and at 1, 9, and 12 months. An independent core laboratory evaluated ultrasound results at 1, 9, and 12 months. RESULTS: The primary endpoint met the prespecified performance goal, with only 3.4% (4/117) of patients experiencing a major adverse event by 9 months (p<0.0001). By 12 months, 6 (5.4%) of 111 patients had TVR; none had an index limb amputation. The ankle-brachial index, Walking Impairment Questionnaire, and Rutherford classifications all showed sustained improvements through 12 months. Primary patency was 94.4% with comparable results for lesions classified as complex (TASC II C/D 95.5%) or non-complex (TASC II A/B 95.0%). CONCLUSION: The EPIC stent system demonstrated safety and effectiveness through 12 months, including improvements for complex lesions. The EPIC stent is a viable alternative to surgery for patients with either complex or non-complex lesions.

Endovascular abdominal aortic aneurysm repair in patients with ventricular assist devices.

Long-term mechanical circulatory support devices are currently an established therapy for the management of end-stage heart failure, and current evidence supports their superiority in comparison to maximal medical therapy in these patients. Screening for peripheral arterial disease and abdominal aortic aneurysm (AAA) before left ventricular assist device (LVAD) implantation is recommended. Although repair of AAA before or during LVAD placement has been reported, management of patients with AAA after LVAD implantation needs to be further investigated. We describe our management and operative strategies in 2 patients on destination LVAD therapy who underwent successful endovascular AAA repair.

An unusual case of familial lymphedema.

A 47-year-old man with stable stage II chronic kidney disease and episodic diarrhea presented with chronic, progressive bilateral lower extremity lymphedema. His mother and 2 brothers had similar acral swelling. Thus, a diagnosis of typical primary familial lymphedema was suspected. Approximately 1 year later, progressive azotemia and proteinuria ensued. A renal biopsy suggested Fabry disease, which was confirmed by enzymatic and genetic testing. In addition, Fabry disease was diagnosed in his mother and 2 male siblings with lower extremity lymphedema. As this case illustrates, Fabry disease is an underappreciated and often unrecognized cause of familial lymphedema.

Advanced malignant mesothelioma mimicking acute contained thoracic aortic rupture.

In the emergent setting, patients presenting with acute interscapular pain along with haemodynamic instability require immediate evaluation. We describe the case of a patient in which computed tomographic scanning demonstrated a large hyper-dense, periaortic collection on post-contrast imaging. Urgent endovascular repair was performed for descending thoracic aortic rupture. Her postoperative course, however, was atypical with a readmission 1 week after discharge with symptoms similar to her primary presentation. Alternative pathologies were then considered in a more elective setting in which the correct diagnosis of diffuse malignant mesothelioma was ultimately discovered in a patient with no previous exposure to occupational toxins. The tumour burden was advanced and the patient opted for palliative care. Herein, we suggest a consideration for oncological thoracic pathology in patients presenting with signs and symptoms mimicking acute thoracic aortic rupture or dissection, who may demonstrate atypical symptoms.

Penetration of the inferior vena cava and adjacent organs after filter placement is associated with retrievable filter type and length of time in place.

OBJECTIVE: Concern over local complications of inferior vena cava (IVC) filters exists, but little long-term data are available. Referrals for filter penetrations on computed tomography (CT) have increased with no standards for management. We reviewed postfilter CT findings in our institution. METHODS: All patients receiving IVC filters between January 1, 2006 and December 31, 2009 with a postfilter CT were reviewed. Penetration was graded with a previously published scale. Filter indication, type, and subsequent encounters for abdominal or back pain were recorded. RESULTS: A total of 591 patients had a filter during the study period. Of these, 262 had an adequate postfilter CT, comprising the study group. Indications were prophylaxis in 16.4% and venous thromboembolism in 83.6%. Of filters placed for venous thromboembolism, indications were absolute (inability/failure of anticoagulation) in 44.7% and relative in 55.3%. Retrievable filters made up 92.7% of the filters, and 7.3% were permanent type. Of the retrievable filters, 1.6% were retrieved. One hundred twenty (45.8%) filters had grade 2 or 3 penetration. Another 38.2% (100) had struts immediately adjacent to the external aspect of the IVC, which may represent tenting of the cava. Grade 2 or 3 penetration occurred in 49.0% of retrievable filters but only 5.3% of permanent filters (P = .0001). Grade 2 or 3 penetration occurred in 18.2% of filters less than 30 days old but in 57.3% of filters 30 days old or older (P < .0001). Thirty-two patients had subsequent encounters for abdominal or back pain, but none was conclusively related to penetration. CONCLUSIONS: A majority of filters were placed for prophylaxis or relative indications and were retrievable type. Retrieval rate was low. Penetration of the IVC and adjacent organs was common and associated with retrievable type and length of time in place. It is unclear if most penetrations cause problems. Monitoring of penetrations with CT may be important to understand the natural history of this condition.

Diseases of the thoracic aorta in women.

Women have now equaled or surpassed men in the number of cardiovascular deaths per year in published statistics. In 2006, according to the National Center for Health Statistics and the Center for Disease Control, cardiovascular disease was the cause of death in 428,906 women (35% of all deaths in women) and in 394,840 men (33% of all deaths in men). Of those numbers, it was estimated that 5506 women (0.4% of all deaths in women) and 7732 men (0.6%) died because of aortic aneurysm or dissection. Currently, aortic disease ranks as the 19th leading cause of death with reported increases in incidence. Historically, aortic disease is thought to affect men more frequently than women with a varying reported gender ratio. Gender bias has long been implicated as an important factor, but often overlooked, in the analysis and interpretation of cardiovascular diseases outcome, in part, because of the under-representation of women in clinical trials and studies. In this section, we provide an up-to-date review of the epidemiology and management of common diseases of the thoracic aorta, focusing on the differences and similarities in women and men.

Abdominal aortic aneurysms in women.

Abdominal aortic aneurysms have an incidence that is approximately four to six times higher in men than in women. However, the incidence in women also rises with older age, although starting later in life than in men. There are also sex differences in the risk of rupture and in outcomes after endovascular and open abdominal aortic aneurysm repair. Various explanations have been proposed. Women historically have been under-represented in clinical trials to evaluate the differences between the sexes. We present a review of current recommendations and recent literature to help identify some of these differences.

External iliac artery stenting: high incidence of concomitant revascularization procedures.

OBJECTIVES: To review immediate results, patency rates, hemodynamic success, and incidence of concomitant procedures with external iliac artery stenting (EIAS). METHODS: Demographic features, category and clinical grade, Trans-Atlantic Inter-Society Consensus II classification lesion type, pre- and postprocedure ankle-brachial indices, and primary patency were compared between group 1 (EIAS without distal revascularization) and group 2 (EIAS with concomitant distal revascularization). RESULTS: No mortality and a 100% immediate technical success rate was recorded in group 1 (n = 12) and group 2 (n = 24). Eleven patients (30.6%) also had stenting of the adjacent common iliac artery. Two thirds of group 2 patients required concomitant femoral or distal revascularization. CONCLUSIONS: No difference in stent patency rates was found between patients in group 1 versus group 2. Patients requiring EIAS tend to have more diffuse arterial disease necessitating complicated open reconstruction and/or distal revascularization, as well as more proximal iliac stenting.