One-year volume growth of abdominal aortic aneurysms measured by extended field-of-view ultrasound.

BACKGROUND: Measurement of volume has the potential to detect subtle growth not recognized in the current surveillance paradigm of abdominal aortic aneurysms (AAAs). Currently available three-dimensional ultrasound allows for estimation of AAA volume, but for most patients, the AAA extends beyond the ultrasound field-of-view and only allows visualization of a partial AAA volume. A new extended field-of-view three-dimensional ultrasound protocol (XFoV US) has been found to improve the proportion of patients with visualization of the full AAA volume. METHODS: To investigate the applicability of the XFoV US protocol in estimating AAA volume growth in follow-up, 86 patients with AAAs were recruited from the surveillance program at a university hospital. All were imaged by XFoV US at baseline and at one-year follow-up. RESULTS: Assessment of full volume, based on visualization of the AAA neck and bifurcation at both baseline and one-year follow-up, was achieved in 67/86 (78%) of patients. One-year mean growth in maximum diameter was 2.8 mm (6%/year), in centerline length 2.9 mm (4%/year), and in volume 15.9 mL (19%/year). In 17/67 (25%) of patients, volume growth was detected in diameter-stable AAAs. Baseline XFoV US volume was associated with one-year AAA volume growth, while, conversely, maximum baseline diameter was not associated with one-year AAA diameter growth. CONCLUSIONS: This study concludes that the XFoV US protocol provides a safe and repeatable modality for assessing AAA volume growth, and that AAA volume is a promising predictive measure of AAA growth.

The Short-term Predictive Value of Vessel Wall Stiffness on Abdominal Aortic Aneurysm Growth.

BACKGROUND: Abdominal aortic aneurysm (AAA) surveillance programs are currently based solely on AAA diameter. The diameter criterion alone, however, seems inadequate as small AAAs comprise 5-10 % of ruptured AAAs as well as some large AAAs never rupture. Aneurysm wall stiffness has been suggested to predict rupture and growth; this study aimed to investigate the prognostic value of AAA vessel wall stiffness for growth on prospectively collected data. METHODS: Analysis was based on data from a randomised, placebo-controlled, multicentre trial investigating mast-cell-inhibitors to halt aneurysm growth (the AORTA trial). Systolic and diastolic AAA diameter was determined in 326 patients using electrocardiogram-gated ultrasound (US). Stiffness was calculated at baseline and after 1 year. RESULTS: Maximum AAA diameter increased from 44.1 mm to 46.5 mm during the study period. Aneurysm growth after 1 year was not predicted by baseline stiffness (-0.003 mm/U; 95 % CI: -0.007 to 0.001 mm/U; P = 0.15). Throughout the study period, stiffness remained unchanged (8.3 U; 95 % CI: -2.5 to 19.1 U; P = 0.13) and without significant correlation to aneurysm growth (R: 0.053; P = 0.38). CONCLUSIONS: Following a rigorous US protocol, this study could not confirm AAA vessel wall stiffness as a predictor of aneurysm growth in a 1-year follow-up design. The need for new and subtle methods to complement diameter for improved AAA risk assessment is warranted.

Three- and Two-Dimensional Ultrasound is as Accurate as Computed Tomography in Aortic Sac Assessment after Endovascular Aortic Repair.

BACKGROUND: To compare aortic sac changes after endovascular aneurysm repair (EVAR) assessed by three-dimensional ultrasound (3D-US), two-dimensional ultrasound (2D-US), and traditional computed tomographic angiography (CTA). METHODS: Using volume assessment with three-dimensional CTA (3D-CTA-volume) as the gold standard, this study investigated aortic sac changes at three and 12 months after EVAR with three different ultrasound methods (2D-US anterior-posterior (AP) diameter, 3D-US AP centerline diameter, and 3D-US partial volume), and traditional CT multiplanar outer-to-outer diameter (CT-MPR OTO diameter). From august 1st, 2011 to January 2014, consecutive EVAR patients (n = 113) were available for analysis in two time intervals; 1) between preoperative and three-month follow-up and 2) between three and 12 month follow-up. RESULTS: The risk of missing true aortic sac growth (false negative finding) at three-month postoperative visit using 3D-US partial volume, 3D-US AP centerline diameter, 2D-US AP diameter, and CT-MPR OTO diameter was 19%, 21%, 22%, and 18%, respectively. Corresponding low sensitivities (0% to 21%) and kappa-values (<0.50) in detecting aortic sac changes were found. The risk of missing true growth between three and 12 months were lower (6%, 5%, 6%, and 6%, respectively), and matching sensitivities 33%, 33%, 17%, and 17%, respectively. CONCLUSIONS: All tested methods for aortic sac changes were as good as traditional CT-MPR OTO diameter and corresponded poorly with 3D-CTA-volume at three months postoperative visit but substantially better after 12 months where the residual sac change was more profound.

European Society for Vascular Surgery (ESVS) Certification of Theoretical and Practical Competences in Basic Vascular Ultrasound: Validity Investigation of the Assessment Tools.

OBJECTIVE: The aim of this study was to gather validity evidence for the Assessment of basic Vascular Ultrasound Expertise (AVAUSE) tool, and to establish a pass/fail score for each component, to support decisions for certification. METHODS: A cross sectional validation study performed during the European Society for Vascular Surgery's annual meeting. Validity evidence was sought for the theoretical test and two practical tests based on Messick's framework. The participants were vascular surgeons, vascular surgical trainees, sonographers, and nurses with varying experience levels. Five vascular ultrasound experts developed the theoretical and two practical test components of the AVAUSE tool for each test component. Two stations were set up for carotid examinations and two for superficial venous incompetence (SVI) examinations. Eight raters were assigned in pairs to each station. Three methods were used to set pass/fail scores: contrasting groups' method; rater consensus; and extended Angoff. RESULTS: Nineteen participants were enrolled. Acceptable internal consistency reliability (Cronbach's alpha) for the AVAUSE theoretical (0.93), carotid (0.84), and SVI (0.65) practical test were shown. In the carotid examination, inter-rater reliability (IRR) for the two rater pairs was good: 0.68 and 0.78, respectively. The carotid scores correlated significantly with years of experience (Pearson's r = 0.56, p = .013) but not with number of examinations in the last five years. For SVI, IRR was excellent at 0.81 and 0.87. SVI performance scores did not correlate with years of experience and number of examinations. The pass/fail score set by the contrasting groups' method was 29 points out of 50. The rater set pass/fail scores were 3.0 points for both carotid and SVI examinations and were used to determine successful participants. Ten of 19 participants passed the tests and were certified. CONCLUSION: Validity evidence was sought and established for the AVAUSE comprehensive tool, including pass/fail standards. AVAUSE can be used to assess competences in basic vascular ultrasound, allowing operators to progress towards independent practice.

Cutdown Technique is Superior to Fascial Closure for Femoral Artery Access after Elective Endovascular Aortic Repair.

OBJECTIVES: Arterial access closure after endovascular aneurysm repair (EVAR) can be achieved using three different approaches: percutaneous closure devices, surgical exposure and direct suture ("cutdown"), and the less invasive fascial closure technique. The aim of this study was to report on the intra-operative, in hospital, and three month outcome of fascial closure and cutdown, and to determine risk factors for failure. METHODS: The primary outcome was assessed in 439 groins in 225 elective EVAR patients recruited consecutively and prospectively from February 1, 2011 to August 31, 2014. During the study period, fascial closure and cutdown were first and second line closing techniques. Compared with fascial closure, procedures completed with cutdown had lower BMI, thinner subcutaneous tissue of the groin and more complex femoral anatomy. Computed tomographic angiography (CTA) and duplex ultrasound (DUS) of the groin were performed pre-operatively and three months after EVAR. Retrospective review of medical records and CTA were used to determine intra-operative and in hospital outcome, and risk factors for failure. RESULTS: In total, 64%, 33%, and 3% were completed with fascial closure, cutdown, and closure device, respectively. Intra-operative, in hospital, and three month technical success rates of fascial closure vs. cutdown were 91% (283/310 groins) vs. 99% (114/115 groins), 89% (277/310 groins) vs. 99% (114/115 groins), and 89% (275/310 groins) vs. 99% (114/115 groins) (p < .001). Wound complications within three months were infrequent for both methods. No risk factor was significantly associated with failure after fascial closure. CONCLUSION: This study shows that cutdown is superior to fascial closure for femoral artery access after elective EVAR. In acute EVAR, however, fascial closure is still considered to be a good and fast method, and it has been kept in the present authors' armamentarium for this indication.

von Willebrand Factor and Prekallikrein in Plasma Are Associated With Thrombus Volume in Abdominal Aortic Aneurysms.

OBJECTIVES: Disruption of the endothelial lining may be one of the events linking intraluminal thrombus and abdominal aortic aneurysm growth. In the present study, we examined whether von Willebrand factor activity in plasma, contact proteins of blood coagulation, and inflammatory biomarkers may be associated with intraluminal thrombus volume in search of a biochemical marker of endothelial damage and thrombus size. DESIGN: Prospective study, correlating potential endothelial biomarkers and intraluminal thrombus volume acquired by computed tomography angiography. MATERIALS AND METHODS: Plasma was consecutively obtained from 38 patients with asymptomatic infrarenal abdominal aortic aneurysm. von Willebrand factor activity, thrombin generation time, factor XII, and prekallikrein concentration were measured in plasma on automated and in-house platforms. In total, 8 patients were excluded due to ongoing anticoagulant therapy, renal impairment, or nonappearance, thus leaving 30 patients for further analysis. All patients had computed tomography angiography, and intraluminal volume was quantified off-line by OsiriX 6.5. RESULTS: Median intraluminal thrombus volume was 42.7 mL. Spearman correlation analysis revealed a positive correlation between thrombus volume, von Willebrand factor activity (ρ = 0.56, P = .0013), and prekallikrein concentration in plasma (ρ = 0.54, P = .002). CONCLUSION: von Willebrand factor activity and concentration of prekallikrein may both be of importance regarding the evolution of thrombus in abdominal aortic aneurysm and possible biomarkers for aneurysm growth.

[Median arcuate ligament syndrome]. / Truncus coeliacus-kompressionssyndrom.

The median arcuate ligament syndrome is a rare entity and poorly described in Danish literature. The syndrome is a diagnosis of exclusion and is characterized by chronic abdominal pain, postprandial pain and weight loss. It is believed that the median arcuate ligament, being a fibrous structure of diaphragm, compresses the coeliac trunk thus causing stenosis and malperfusion of the gastrointestinal organs. Until recently, there has been some reluctance to consider intervention with revascularization or ligament release. Within the latest decade minimally invasive techniques, including laparoscopic release of the median arcuate ligament, have shown promising results.