Secondary Fill Minimizes Gutter Size in Chimney EVAS Configurations In Vitro.

PURPOSE: To investigate in an in vitro model if secondary endobag filling can reduce gutter size during chimney endovascular aneurysm sealing (chEVAS). MATERIALS AND METHODS: Nellix EVAS systems were deployed in 2 silicone juxtarenal aneurysm models with suprarenal aortic diameters of 19 and 24 mm. Four configurations were tested: EVAS with 6-mm balloon-expandable (BE) or self-expanding (SE) chimney grafts (CGs) in the renal branches of both models. Balloons were inflated simultaneously in the CGs and main endografts during primary and secondary endobag filling and polymer curing. Computed tomography (CT) was performed immediately after the primary and secondary fills. Cross-sectional lumen areas were measured on the CT images to calculate gutter volumes and percent change. CG compression was calculated as the reduction in lumen surface area measured perpendicular to the central lumen line. The largest gutter volume and highest compression were presented per CG configuration per model. RESULTS: Secondary endobag filling reduced the largest gutter volumes from 99.4 to 73.1 mm3 (13.2% change) and 84.2 to 72.0 mm3 (27.6% change) in the BECG configurations and from 67.2 to 44.0 mm3 (34.5% change) and 92.7 to 82.3 mm3 (11.2% change) in the SECG configurations in the 19- and 24-mm models, respectively. Secondary endobag filling increased CG compression in 6 of 8 configurations. BECG compression changed by -0.2% and 5.4% and by -1.0% and 0.4% in the 19- and 24-mm models, respectively. SECG compression changed by 10.2% and 16.0% and by 7.2% and 7.3% in the 19- and 24-mm models, respectively. CONCLUSION: Secondary endobag filling reduced paragraft gutters; however, this technique did not obliterate them. Increased CG compression and prolonged renal ischemia time should be considered if secondary endobag filling is used.

Endovascular repair of a ruptured pararenal aortic aneurysm using the Nellix endovascular aneurysm sealing system and chimney grafts.

PURPOSE: To demonstrate the feasibility of emergent endovascular repair of a ruptured pararenal aneurysm using chimney grafts and the Nellix endovascular aneurysm sealing (EVAS) system to reduce the potential for endoleak from the gutters around the chimney grafts. CASE REPORT: A 74-year-old patient presented with a ruptured pararenal aneurysm. Because of anatomical considerations after previous aortic surgery, conventional endovascular aneurysm repair was deemed impossible. It was decided to exclude the aneurysm with a Nellix EVAS system in conjunction with two chimneys to the renal arteries, even though this was outside the instructions for use of the device. Active bleeding was stopped directly after positioning the chimneys and filling the endobags with polymer. Completion angiography showed aneurysm exclusion and patent renal arteries. Renal function remained stable, and the patient was discharged at the third postoperative day. At 6 months, duplex ultrasound and computed tomography showed patent stents and chimneys and no evidence of endoleak. CONCLUSION: Using chimney grafts in combination with the Nellix endoprosthesis in a ruptured pararenal aneurysm is feasible. However, more robust data on both chimney-EVAS and EVAS in ruptured cases are required.

Thoracic Endovascular Aneurysm Repair and Tracheal Stenting for Respiratory Failure due to a Thoracic Aortic Aneurysm: A Case Report.

An 82-year-old male was referred to the emergency department for severe respiratory distress. Computed tomography angiography showed tracheal compression due to a large ruptured saccular aneurysm of the descending thoracic aorta. Emergency Thoracic Endovascular Aneurysm Repair (TEVAR) was performed. To reduce tracheal compression, an endotracheal stent was placed (silicone Dumon©). Following surgery, respiratory function improved. Two days after the surgery, the patient refused further invasive treatment, including mechanical mucus aspiration from the endotracheal stent, and palliative sedation was initiated. Conventional treatment to reduce tracheal compression by a saccular aortic aneurysm is open surgical aneurysm repair. If open repair is contraindicated because of patient age, comorbidity, or in case of severe hemodynamic instability following aneurysm rupture, TEVAR with endotracheal stent placement may serve as a bridge to definite surgery to reduce tracheal compression.

Life-Threatening Non-Allergic Drug Hypersensitivity Reaction as a Very Rare Side Effect of Rivaroxaban Administration in the Netherlands.

BACKGROUND: Anticoagulant therapy is indicated for the prevention and treatment of thromboembolic disease. Direct oral anticoagulants (DOACs) are frequently prescribed and Rivaroxaban is the most frequently administered DOAC in the Netherlands. Most side effects relate to hemorrhagic complications, however, also non-hemorrhagic side effect may be potentially life threatening. CASE PRESENTATION: A 74-year-old man presented at the emergency department with a ruptured infrarenal abdominal aortic aneurysm for which open aneurysm repair was performed. Postoperatively, the patient developed neurological deficit, respiratory and circulatory failure following rivaroxaban administration, initiated for atrial fibrillation. Even though, the clinical signs resembled an anaphylactic reaction, the skin-prick test was negative and complications most likely resulted from a non-allergic drug hypersensitivity reaction. CONCLUSION: This case report shows that non-allergic drug hypersensitivity reactions may mimic an anaphylactic reaction and can be potentially life threatening. In addition, severe non-hemorrhagic complications after rivaroxaban administration do occur and should be considered in case of acute clinical deterioration.

[Fever and persisting calf abscess ten years after aorta-bifemoral bypass]. / Koorts en een kuitabces door geïnfecteerde aortaprothese.

A 52-year-old woman presented with fever and a persisting calf abscess ten years after she had received an aorta-bifemoral bypass. Her infection parameters were increased and she had anaemia. CT of the abdomen revealed air surrounding the proximal anastomosis of the bypass suggesting bypass graft infection. The diagnosis of an aorta-duodenal fistula was confirmed by gastroduodenoscopy showing migration of the bypass through the wall of the duodenum into the intestinal lumen. The bypass was resected and reconstructed using the superficial femoral vein. The patient recovered uneventful.

Anatomic Suitability for Branched Thoracic Endovascular Repair in Patients with Aortic Arch Pathological Features.

Background Endovascular repair has become a viable alternative for aortic pathological features, including those located within the aortic arch. We investigated the anatomic suitability for branched thoracic endovascular repair in patients previously treated with conventional open surgery for aortic arch pathological features. Methods and Results Patients who underwent open surgery for aortic arch pathological features at our institution between 2000 and 2018 were included. Anatomic suitability was determined by strict compliance with the anatomic criteria within manufacturers' instructions for use for each of the following branched thoracic stent grafts: Relay Plus Double-Branched (Terumo-Aortic), TAG Thoracic Branch Endoprosthesis (W.L. Gore & Associates), Zenith Arch Branched Device (Cook-Medical), and Nexus Stent Graft System (Endospan Ltd/Jotec GmbH). Computed tomography angiography images were analyzed with outer luminal line measurements. A total of 377 patients (mean age, 64±14 years; 64% men) were identified, 153 of whom had suitable computed tomography angiography images for measurements. In total, 59 patients (15.6% of the total cohort and 38.6% of the measured cohort) were eligible for endovascular repair using at least one of the devices. Device suitability was 30.9% for thoracic aneurysms, 4.6% for type A dissections, 62.5% for type B dissections, and 28.6% for other pathological features. Conclusions The anatomic suitability for endovascular repair of all aortic arch pathological features was modest. The highest suitability rates were observed for thoracic aneurysms and for type B dissections, of which repair included part of the aortic arch. We suggest endovascular repair of arch pathological features should be reserved for high-volume centers with experience in endovascular arch repair.

Incidental finding of malignancy in patients preoperatively evaluated for aneurysm wall pathology using PET/CT.

Preoperative positron emission tomography/computed tomography (PET/CT) was performed in 26 consecutive patients considered fit for aneurysm repair. Besides information on aneurysm wall pathology, PET/CT identified 6 patients with concomitant malignancy. As a result of this coincidental finding, the operation was postponed in 2 patients and cancelled in 1. Although previous studies have shown that PET/CT might affect patient selection based on aneurysm wall inflammation, our preliminary results show a big impact on patient management as a result of the sensitivity of PET/CT for detecting malignancy. Future larger studies are warranted to investigate the effect and cost effectiveness of routine PET/CT in abdominal aortic aneurysm (AAA) patients.

In-vivo imaging of changes in abdominal aortic aneurysm thrombus volume during the cardiac cycle.

PURPOSE: To evaluate in-vivo thrombus compressibility in abdominal aortic aneurysms (AAAs) to hopefully shed light on the biomechanical importance of intraluminal thrombus. METHODS: Dynamic electrocardiographically-gated computed tomographic angiography was performed in 17 AAA patients (15 men; mean age 73 years, range 69-76): 11 scheduled for surgical repair and 6 under routine surveillance. The volumes of intraluminal thrombus, the lumen, and the total aneurysm were quantified for each phase of the cardiac cycle. Thrombus compressibility was defined as the percent change in thrombus volume between diastole and peak systole. Continuous data are presented as medians and interquartile ranges (IQR). RESULTS: A substantial interpatient variability was observed in thrombus compressibility, ranging from 0.4% to 43.6% (0.2 to 13.5 mL, respectively). Both thrombus and lumen volumes varied substantially during the cardiac cycle. As lumen volume increased (5.2%, IQR 2.8%-8.8%), thrombus volume decreased (3.0%, IQR 1.0%-4.6%). Total aneurysm volume remained relatively constant (1.3%, IQR 0.4-1.9%). Changes in lumen volume were inversely correlated with changes in thrombus volume (r = -0.73; p = 0.001). CONCLUSION: In-vivo thrombus compressibility varied from patient to patient, and this variation was irrespective of aneurysm size, pulse pressure, and thrombus volume. This suggests that thrombus might act as a biomechanical buffer in some, while it has virtually no effect in others. Whether differences in thrombus compressibility alter the risk of rupture will be the focus of future research.

Impact of dynamic computed tomographic angiography on endograft sizing for endovascular aneurysm repair.

PURPOSE: To quantify dynamic changes in aortoiliac dimensions using dynamic electrocardiographically (ECG)-gated computed tomographic angiography (CTA) and to investigate any potential impact on preoperative endograft sizing in relation to observer variability. METHODS: Dynamic ECG-gated CTA was performed in 18 patients with abdominal aortic aneurysms. Postprocessing resulted in 11 datasets per patient: 1 static CTA and 10 dynamic CTA series. Vessel diameter, length, and angulation were measured for all phases of the cardiac cycle. The differences between diastolic and systolic aneurysm dimensions were analyzed for significance using paired t tests. To assess intraobserver variability, 20 randomly selected datasets were analyzed twice. Intraobserver repeatability coefficients (RC) were calculated using Bland-Altman analysis. RESULTS: Mean aortic diameter at the proximal neck was 21.4+/-3.0 mm at diastole and 23.2+/-2.9 mm at systole, a mean increase of 1.8+/-0.4 mm (8.5%, p<0.01). The RC for the aortic diameter at the level of the proximal aneurysm neck was 1.9 mm (8.9%). At the distal sealing zones, the mean increase in diameter was 1.7+/-0.3 mm (14.1%, p<0.01) for the right and 1.8+/-0.5 mm (14.2%, p<0.01) for the left common iliac artery (CIA). At both distal sealing zones, the mean increase in CIA diameter exceeded the RC (10.0% for the right CIA and 12.6% for the left CIA). CONCLUSION: The observed changes in aneurysm dimension during the cardiac cycle are small and in the range of intraobserver variability, so dynamic changes in proximal aneurysm neck diameter and aneurysm length likely have little impact on preoperative endograft selection. However, changes in diameter at the distal sealing zones may be relevant to sizing, so distal oversizing of up to 20% should be considered to prevent distal type I endoleak.

In vivo imaging of the aneurysm wall with MRI and a macrophage-specific contrast agent.

OBJECTIVE: Because of their capability of secreting proteinases, macrophages play a central role in the growth and rupture of aneurysms. Noninvasive imaging of macrophages therefore may yield valuable information about the pathogenesis of aneurysm disease. We studied uptake of the macrophage-specific contrast agent ultrasmall paramagnetic iron oxide (USPIO) in the walls of aneurysms and normal-sized aortas. MATERIALS AND METHODS: Six patients with an aortic and five patients with an iliac aneurysm and 11 age-matched controls were identified in a database of 239 patients who underwent evaluations for the staging of prostate cancer. USPIO-enhanced MRI and contrast-enhanced MDCT were performed for all patients. The presence of USPIO was assessed with an iron-sensitive MRI sequence. Quantification consisted of counting the number of quadrants with USPIO-induced subendothelial signal voids. A chi-square test was used to analyze the significance of the difference between the number of USPIO-positive quadrants in the aneurysm group and that in the control group. RESULTS: The number of USPIO-positive quadrants was significantly higher in the aneurysm than in the control group: 158 quadrants (4.2%) in the aneurysm group and 13 quadrants (0.4%) in the control group (p < 0.001). Two abdominal aortic aneurysms accounted for 90% (154/171) of all USPIO-positive quadrants. CONCLUSION: USPIO uptake is limited or absent in the wall of normal-sized aortas and most aneurysms. However, individual abdominal aortic aneurysms exhibit high levels of USPIO uptake, indicative of extensive macrophage infiltration in the aneurysm wall. Future research should focus on the predictive value of USPIO uptake for growth and rupture of aneurysms.

Systematic Review of Circulating, Biomechanical, and Genetic Markers for the Prediction of Abdominal Aortic Aneurysm Growth and Rupture.

BACKGROUND: The natural course of abdominal aortic aneurysms (AAA) is growth and rupture if left untreated. Numerous markers have been investigated; however, none are broadly acknowledged. Our aim was to identify potential prognostic markers for AAA growth and rupture. METHODS AND RESULTS: Potential circulating, biomechanical, and genetic markers were studied. A comprehensive search was conducted in PubMed, Embase, and Cochrane Library in February 2017, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Study selection, data extraction, and methodological quality assessment were conducted by 2 independent researchers. Plausibility of markers was based on the amount of publications regarding the marker (more than 3), pooled sample size (more than 100), bias risk and statistical significance of the studies. Eighty-two studies were included, which examined circulating (n=40), biomechanical (n=27), and genetic markers (n=7) and combinations of markers (n=8). Factors with an increased expansion risk included: AAA diameter (9 studies; n=1938; low bias risk), chlamydophila pneumonia (4 studies; n=311; medium bias risk), S-elastin peptides (3 studies; n=205; medium bias risk), fluorodeoxyglucose uptake (3 studies; n=104; medium bias risk), and intraluminal thrombus size (5 studies; n=758; medium bias risk). Factors with an increased rupture risk rupture included: peak wall stress (9 studies; n=579; medium bias risk) and AAA diameter (8 studies; n=354; medium bias risk). No meta-analysis was conducted because of clinical and methodological heterogeneity. CONCLUSIONS: We identified 5 potential markers with a prognostic value for AAA growth and 2 for rupture. While interpreting these data, one must realize that conclusions are based on small sample sizes and clinical and methodological heterogeneity. Prospective and methodological consonant studies are strongly urged to further study these potential markers.

Superficial temporal artery aneurysm: Diagnosis and treatment options.

BACKGROUND: Superficial temporal artery (STA) aneurysms are an uncommon entity and mostly described in case studies. The purpose of this review was to show the studied clinical presentation, diagnostic modalities, and treatment modalities of STA aneurysms. METHODS: A review was performed of reports on STA aneurysms published until December 2010, using the MEDLINE and Cochrane databases. RESULTS: One hundred sixty-six pseudoaneurysms and 20 true aneurysms were described. The majority of patients presented with a painless pulsatile mass. Historically, angiography was most often used, but ultrasound scan, CT, and MRI may be superior. Surgical resection was performed in 128 pseudoaneurysms and 20 true aneurysms with 1 recurrence and few complications. Endovascular approaches were used in 13% of pseudoaneurysms with an 80% success rate. CONCLUSION: Pseudoaneurysms are mostly the result of blunt trauma as opposed to true aneurysms which usually occur spontaneously. Surgical resection is a safe treatment modality, but endovascular treatment might be considered in a selected group of patients. © 2012 Wiley Periodicals, Inc. Head Neck, 2013.

In vivo imaging of abdominal aortic aneurysms: increased FDG uptake suggests inflammation in the aneurysm wall.

PURPOSE: To study the potential of integrated positron emission tomography and computed tomography (PET/CT) to identify aneurysm wall inflammation. METHODS: The level of F18-fluorodeoxyglucose (FDG) uptake was studied in aneurysmal and normal-sized aortas of 34 male patients [17 with abdominal aortic aneurysm (AAA) and 17 age-matched controls] identified in a database of 278 consecutive patients evaluated for staging of primary lung cancer. The maximal standardized uptake value (SUV) was calculated to quantify FDG uptake in the AAA wall. RESULTS: AAAs showed significantly higher FDG uptake than the normal-sized aorta in age-matched controls (SUV 2.52+/-0.52 versus 1.78+/-0.45, respectively; p<0.001). The level of FDG uptake did not correlate with maximal aneurysm diameter (r=0.09; 95% CI -0.42 to 0.56; p=0.7). CONCLUSION: FDG-PET/CT is a promising technique to identify inflammation of the aneurysm wall. Irrespective of aneurysm diameter, asymptomatic AAAs show more FDG uptake and more inflammatory activity in the wall than the non-dilated abdominal aorta of sex/age-matched controls. Future studies will be directed at the predictive value of increased FDG uptake for aneurysm wall strength, rupture risk, and the utility of FDG-PET/CT in assessing the effect of medical interventions.