Intraobserver and interobserver variability of 64-row computed tomography abdominal aortic aneurysm neck measurements

BACKGROUND: Integrity of the abdominal aortic aneurysm (AAA) neck is crucial for the long-term success of endovascular AAA repair (EVAR). However, suitable tools for reliable assessment of changes in small aortic volumes are lacking. The purpose of this study was to assess the intraobserver and interobserver variability of software-enhanced 64-row computed tomographic angiography (CTA) AAA neck volume measurements in patients after EVAR. METHODS: A total of 25 consecutive patients successfully treated by EVAR underwent 64-row follow-up CTA in 1.5-mm collimation. Manual CTA measurements were performed twice by three blinded and independent readers in random order with at least a 4-week interval between readings. Maximum and minimum transverse aortic neck diameters were measured twice on two different levels within the proximal neck. Volumetry of the proximal aortic neck was performed by using dedicated software. Variability was calculated as 1.96 SD of the mean arithmetic difference according to Bland and Altman. Two-sided and paired t tests were used to compare measurements. P values <.05 were considered to indicate statistical significance. RESULTS: Intraobserver agreement was excellent for dedicated aneurysmal neck volumetry, with mean differences of less than 1 mL (P > .05), whereas it was poor for transverse aortic neck diameter measurements (P < .05). However, interobserver variability was statistically significant for both neck volumetry (P < .005) and neck diameter measurements (P < .015). CONCLUSIONS: The reliability of dedicated AAA neck volumetry by using 64-row CTA is excellent for serial measurements by individual readers, but not between different readers. Therefore, studies should be performed with aortic neck volumetry by a single experienced reader.

Internal iliac artery embolization before endovascular repair of aortoiliac aneurysms with a nitinol vascular occlusion plug

PURPOSE: To evaluate the acute and midterm effectiveness of a novel vascular occlusion device for embolization of the internal iliac artery (IIA) before endovascular repair of aortoiliac aneurysms. MATERIALS AND METHODS: Between March 2005 and April 2006, nine men (mean age, 75 years +/- 5; range, 66-83 y) with aortoiliac aneurysms underwent bifurcated endovascular stent-graft procedures. All these patients were referred specifically for embolization. Pre- and perioperatively, eight patients underwent unilateral embolization and one underwent bilateral embolization of the IIA to prevent type II endoleak. Via a contralateral femoral approach with a 6-F or 8-F sheath, the embolization procedure was performed with an Amplatzer Vascular Plug, a self-expandable cylindrical device consisting of a nitinol-based wire mesh. Technical success, clinical outcome, and complications were evaluated. Follow-up at 3, 6, and 12 months was performed with clinical and radiologic examinations. RESULTS: IIA embolization was technically successful in all cases and no procedure-related complications occurred. Imaging at discharge and at 3-, 6-, or 12-month follow-up was accomplished in all nine patients. Control computed tomography and magnetic resonance angiography did not reveal retrograde perfusion of the aneurysmal sac, ie, type II endoleak. Three of nine patients (33.3%) reported symptoms of buttock claudication that did not resolve completely. Clinical symptoms such as bowel ischemia or sexual dysfunction were not observed. CONCLUSIONS: The midterm results of this study suggest that preoperative IIA embolization with a nitinol vascular occlusion plug during endovascular treatment of aortoiliac aneurysms is safe and effective.

Anemia is associated with abdominal aortic aneurysm (AAA) size and decreased long-term survival after endovascular AAA repair

OBJECTIVE: Anemia is a common comorbid condition in various inflammatory states and an established predictor of mortality in patients with chronic heart failure, ischemic heart disease, and end-stage renal disease. The present study of patients with abdominal aortic aneurysm (AAA) undergoing endovascular repair (EVAR) assessed the relationships between baseline hemoglobin concentration and AAA size, as well as anemia and long-term survival. METHODS: Between March 1994 and November 2006, 711 patients (65 women, mean age 75.8 +/- 7.8 years) underwent elective EVAR. Anemia was defined as a hemoglobin level <13 g/dL in men and <12 g/dL in women. Post-EVAR mean follow-up was 48.3 +/- 32.0 months. Association of hemoglobin level with AAA size was assessed with multiple linear regression. Mortality was determined with use of the internet-based Social Security Death Index and the electronic hospital record. Kaplan-Meier survival curves of anemic and nonanemic patient groups were compared by the log-rank method. Multivariable logistic regression models were used to determine the influence of anemia on vital status after EVAR. RESULTS: A total of 218/711 (30.7%) of AAA patients undergoing EVAR had anemia at baseline. After adjustment for various risk factors, hemoglobin level was inversely related to maximum AAA diameter (beta: - .144, 95%-CI: -1.482 - .322, P = .002). Post-EVAR survival was 65.5% at 5 years and 44.4% at 10 years. In long-term follow-up, survival was significantly lower in patients with anemia as compared to patients without anemia (P < .0001 by log-rank). Baseline hemoglobin levels were independently related to long-term mortality in multivariable Cox regression analysis adjusted for various risk factors (adjusted HR: 0.866, 95% CI: .783 to .958, P = .005). Within this model, statin use (adjusted HR: .517, 95% CI: .308 to .868, P = .013) was independently related to long-term survival, whereas baseline AAA diameter (adjusted HR: 1.022, 95% CI: 1.009 to 1.036, P = .001) was an independently associated with increased mortality. CONCLUSIONS: Baseline hemoglobin concentration is independently associated with AAA size and reduced long-term survival following EVAR. Thus, the presence or absence of anemia offers a potential refinement of existing risk stratification instruments.

Novel insight into the pathobiology of abdominal aortic aneurysm and potential future treatment concepts

The patient with abdominal aortic aneurysm (AAA) commonly is a nondiabetic, white man with a history of smoking. Moreover, AAA represents a leading cause of death in elderly men in Western countries. The purpose of this manuscript is to review current evidence as to the pathobiology of AAA as well as potential future drug targets to prevent progression of AAA.

Proteomic alterations in heat shock protein 27 and identification of phosphoproteins in ascending aortic aneurysm associated with bicuspid and tricuspid aortic valve

Whether or not there are molecular differences, at the intra- and extracellular level, between aortic dilatation in patients with bicuspid (BAV) and those with a tricuspid aortic valve (TAV) has remained controversial for years. We have performed 2-dimensional gel electrophoresis and mass spectrometry coupled with dephosphorylation and phosphostaining experiments to reveal and define protein alterations and the high abundant structural phosphoproteins in BAV compared to TAV aortic aneurysm samples. 2-D gel patterns showed a high correlation in protein expression between BAV and TAV specimens (n=10). Few proteins showed significant differences, among those a phosphorylated form of heat shock protein (HSP) 27 with significantly lower expression in BAV compared to TAV aortic samples (p=0.02). The phosphoprotein tracing revealed four different phosphoproteins including Rho GDP dissociation inhibitor 1, calponin 3, myosin regulatory light chain 2 and four differentially phosphorylated forms of HSP27. Levels of total HSP27 and dually phosphorylated HSP27 (S78/S82) were investigated in an extended patient cohort (n=15) using ELISA. Total HSP27 was significantly lower in BAV compared to TAV patients (p=0.03), with no correlation in levels of phospho-HSP27 (S78/S82) (p=0.4). Western blots analysis showed a trend towards lower levels of phospho-HSP27 (S78) in BAV patients (p=0.07). Immunohistochemical analysis revealed that differences in HSP27 occur in the cytoplasma of VSMC's and not extracellularly. Alterations in HSP27 may give early evidence for intracellular differences in aortic aneurysm of patients with BAV and TAV. Whether HSP27 and the defined phosphoproteins have a specific role in BAV associated aortic dilatation remains to be elucidated.

Stenting of common iliac vein obstructions combined with regional thrombolysis and thrombectomy in acute deep vein thrombosis

OBJECTIVES: To evaluate the efficacy of stent placement after infrainguinal loco-regional thrombolysis and iliac thrombectomy (surgical TT) of acute deep vein thrombosis (DVT) in patients with May-Thurner-Syndrome. MATERIAL AND METHODS: We retrospectively analysed a group of 11 patients (9 women) (mean age 34 years, range 16-64 years) with surgical TT and additional intra-operative stenting due to compression of the common iliac vein. Patients underwent venography to demonstrate outflow patency after surgical TT, and to identify any obstruction at the level of the left-sided common iliac vein ("Beckenvenen-Sporn"). Obstruction at the level of arterial crossing was treated using Wallstents placed via an introducer sheath from the inguinal access site. Stents were fully deployed using balloons adjusted to the size of vein. Patients were treated with oral anticoagulants for 6 months, and followed using duplex ultrasonography. RESULTS: Technical success defined as complete vein patency and normal valve function was documented in all 11 patients. One patient needed early stent extension due to residual stenosis. At 6 months follow-up one patient (9%) had an asymptomatic occlusion of the stented common iliac vein. In all 11/11 (100%) patients the femoral segment was found to be patent, and in 1/11 (9%) there was mild reflux with few clinical symptoms of post-thrombotic syndrome. The calculated cumulative primary patency rate for venous iliac stents was 82%, and assisted patency rate was 91%, which remained unchanged over a mean follow-up of 22 months. CONCLUSION: Combining surgical TT and stenting of common iliac vein obstructions in DVT is safe, effective, and results in a acceptable venous patency.

Aortic aneurysm sac pressure measurements after endovascular repair using an implantable remote sensor: initial experience and short-term follow-up

The purpose of this single-center study was to report our initial experience with an implantable remote pressure sensor for aneurysm sac pressure measurement in patients post-endovascular aneurysm repair (EVAR) including short-term follow-up. A pressure sensor (EndoSure, Atlanta, GA) was implanted in 12 patients treated with different commercially available aortic endografts for EVAR. Pressure was read pre- and post-EVAR in the operating room. One-month follow-up (30 days +/- 6 days) was performed including sac pressure readings and IV contrast CT scans. Variables were compared using the paired Student's t test. An intraprocedure type-I endoleak and a type-III endoleak were successfully treated resulting in decreasing sac pressures. In all patients, post-EVAR systolic sac pressure decreased by an average of 33% (P aneurysm diameter pre-EVAR was 6.3 +/- 1.6 cm and post-EVAR 6.0 +/- 1.7 cm (Paneurysm sac was larger only in one patient with a type-III endoleak. Remote sac pressure measurement may provide important information in addition to imaging and may help to reduce the number of follow-up CT scans.

Abciximab for thrombolysis during intracranial aneurysm coiling

INTRODUCTION: Thrombotic events are a common and severe complication of endovascular aneurysm treatment with significant impact on patients' outcome. This study evaluates risk factors for thrombus formation and assesses the efficacy and safety of abciximab for clot dissolution. MATERIALS AND METHODS: All patients treated with abciximab during (41 patients) or shortly after (22 patients) intracranial aneurysm coil embolisation were retrieved from the institutional database (2000 to 2007, 1,250 patients). Sixty-three patients (mean age, 55.3 years, +/-12.8) had received either intra-arterial or intravenous abciximab. Risk factors for clot formation were assessed and the angiographic and clinical outcome evaluated. RESULTS: No aneurysm rupture occurred during or after abciximab application. The intra-procedural rate of total recanalisation was 68.3%. Thromboembolic complications were frequently found in aneurysms of the Acom complex and of the basilar artery, whilst internal carotid artery aneurysms were underrepresented. Two patients died of treatment-related intracranial haemorrhages into preexisting cerebral infarcts. Two patients developed a symptomatic groin haematoma. CONCLUSIONS: Abciximab is efficacious and safe for thrombolysis during and after endovascular intracranial aneurysm treatment in the absence of preexisting ischaemic stroke.

Statins are associated with decreased mortality in abdominal, but not in thoracic aortic aneurysm patients undergoing endovascular repair: propensity score-adjusted analysis

BACKGROUND: Purpose of this study was to compare the correlation of statin use with long-term mortality in patients with abdominal (AAA) and thoracic aortic aneurysm (TAA). PATIENTS AND METHODS: We compared long-term survival of 731 AAA and 59 TAA patients undergoing elective endovascular repair (EVAR). Kaplan-Meier survival curves were compared by the log-rank method. Propensity score-adjusted multivariable logistic regression models were used to determine independent associations of statin use on vital status after EVAR. RESULTS: Statin use was associated with decreased long-term mortality in AAA patients in bivariate and multivariable regression analysis, in which the effect of propensity to receive a statin was considered (adjusted HR: .613, 95%-CI: .379- .993, p = .047) whereas mortality of TAA patients was not associated with use of statins (adjusted HR: 1.795, 95%-CI: .147 -21.942, p = .647). CONCLUSIONS: Use of statins is an independent predictor of decreased mortality after elective EVAR in AAA, but not in TAA patients. These findings indirectly support the concept of a distinct pathogenesis of AAA and TAA.

Aortic neck dilatation after endovascular abdominal aortic aneurysm repair: a word of caution

Continuing aortic neck dilatation, most probably an expression of ongoing aneurysmal wall degeneration of the infrarenal aortic segment, has been shown to seriously impair clinical results after endovascular abdominal aortic aneurysm repair. However, conflicting data on the extent and clinical relevance on this observation have recently been published. This article reviews the recent literature, summarizing our current understanding of the role of aortic neck dilatation after open surgical and endovascular abdominal aortic aneurysm repair. In addition, differences in methodology of studies on aortic neck dilatation are highlighted.