Experimental multiparametric magnetic resonance imaging characterization of iliocaval venous thrombosis pathological changes.

Objective: Iliocaval thrombotic obstruction is a challenging condition, especially because thrombus age and corresponding pathological remodeling at presentation are unknown, which directly impacts management. Our aim was to assess the ability of magnetic resonance imaging (MRI) in determining age thresholds of experimentally created inferior vena cava (IVC) thrombosis in pigs.

Methods: We used a previously described swine model of IVC thrombosis.

Management of the False Lumen in Post Type A Aortic Dissection Arch Aneurysms Treated With Branched Endografts.

Introduction: The treatment of chronic postdissection aneurysms of the aortic arch is a challenge. This study aims to describe false lumen management after aortic arch endovascular repair of post-type A dissection aneurysms treated with a branched endograft.

Methods: In this single-center retrospective observational study, all consecutive patients undergoing endovascular treatment of aneurysmal degeneration of chronic type A aortic dissections following open repair were enrolled.

Endovascular Porcine Model of Iliocaval Venous Thrombosis.

Objective: To develop a large animal model of iliocaval deep venous thrombosis (DVT), which enables development and evaluation of interventional management and existing imaging modalities.

Methods: The experimental protocol consisted of a total endovascular approach. Pigs were percutaneously accessed through the right internal jugular and bilateral femoral veins.

Radiation-induced lower-limb arteriopathy: report of 4 cases and systematic literature review.

Introduction: Radiation-induced arteriopathy (RIA) is a rare complication but may become more common due to the increased use of radiotherapy and the prolonged survival of patients. There is still a lack of evidence concerning treatment options. The aim of this study is to review reported cases of lower-limb RIA in order to provide guidelines for management.

Co-Registration of Peripheral Atherosclerotic Plaques Assessed by Conventional CT Angiography, MicroCT and Histology in Patients with Chronic Limb Threatening Ischaemia.

Objective: To co-register conventional computed tomography angiography (CTA), with ex vivo micro-computed tomography (microCT) and histology of popliteal atherosclerotic plaques. Improving the non-invasive imaging capabilities may be valuable to advance patient care with peripheral arterial obstructive disease towards lesion and individual based treatment.

Methods: In this prospective observational study, 12 popliteal arteries from 11 symptomatic patients who had undergone transfemoral amputations for chronic limb threatening ischaemia and who had pre-operative CTA, were analysed ex vivo by microCT and histology.

Evaluating a Novel Telescoping Catheter Set for Treatment of Central Venous Occlusions.

Background: Central venous occlusive disease (CVOD) is a prevalent problem in patients with end-stage renal disease (ESRD) and can lead to access malfunction or ligation for symptomatic relief. The purpose of this study is to evaluate the efficacy of the TriForce® Peripheral Crossing Set (Cook Medical), a novel reinforced telescoping catheter set designed to provide additional support for crossing difficult central venous occlusions.

Methods: This is a single-center retrospective study from a quaternary referral center.

Critical Review of Large Animal Models for Central Deep Venous Thrombosis.

Objective: To review the existing literature on large animal models of central venous thrombosis (CVT) and to evaluate its relevance in regard to the development and testing of dedicated therapeutics applicable to humans.

Methods: A systematic literature search was conducted in PubMed and Embase. Articles describing an in vivo experimental protocol of CVT in large animals, involving the iliac vein and/or the vena cava and/or the brachiocephalic vein, were included.

Endovascular management of chronic post-dissection aneurysms of the aortic arch.

This article reviews endovascular management of chronic post-dissection aneurysms of the aortic arch. Therapeutic strategies intended for this complex aortic condition are evolving rapidly to allow the treatment of various hostile aortic anatomy and frail patients. Principles, technical considerations, devices and outcomes of each technique are reviewed and summarized.

Pathology and Multimodality Imaging of Acute and Chronic Femoral Stenting in Humans.

Objectives: The objective of this study was to comprehensively evaluate the pathology of acute and chronic femoral stenting in symptomatic atherosclerotic patients and to understand the causes of stent failure (SF) using multimodality imaging including micro-computed tomography.

Background: Although the pathology of coronary stenting has been well studied, the pathology of lower extremity femoral stenting remains poorly understood.

Methods: Twelve stented femoral lesions removed at surgery (n = 10) and at autopsy (n = 2) were obtained from 10 patients (median age 74 years; interquartile range [IQR]: 66 to 82 years) with histories of peripheral artery disease (critical limb ischemia in 7) (7 men and 3 women).

Impact of Cardiac Cycle on Thoracic Aortic Geometry-Morphometric Analysis of Ecg Gated Computed Tomography.

Background: Understanding morphological changes of ascending aorta, aortic arch and descending aorta with cardiac and respiratory motion is critical for planning of endovascular repair of thoracic aorta. The aim of this study was to determine the impact of the cardiac cycle on thoracic aortic geometry.

Methods: In this retrospective study, electrocardiogram-gated cardiac computed tomography from 116 patients who were evaluated for transcatheter aortic valve replacement were reviewed.

Endovascular Treatment for Venous Diseases: Where are the Venous Stents?

There is a growing need for dedicated endovascular devices to treat pathologies affecting the venous system. However, because of a lack of research into venous diseases and treatments, the optimal design, material, and mechanical properties of venous stents remain unknown. Development of the ideal venous stent should be based on a thorough understanding of the underlying venous pathology.

Proposed Magnetic Resonance Imaging Criteria to Diagnose Intramural Haematoma and to Predict Aortic Healing after Acute Type B Aortic Syndrome.

Objective: Type B acute aortic syndrome (AAS) encompasses aortic dissection (AD) and intramural haematoma (IMH), the diagnosis, evolution, and treatment of which are subject to controversies. The aim of this pilot investigation was to assess the ability of specific magnetic resonance imaging (MRI) criteria to differentiate AD from IMH and predict optimal aortic remodeling following AAS.

Methods: In this retrospective study, all patients presenting between 2008 and 2015 with type B AAS, who had diagnostic MRI following admission, were included.

Computed tomography angiography-fluoroscopy image fusion allows visceral vessel cannulation without angiography during fenestrated endovascular aneurysm repair.

Background: Fenestrated endovascular aneurysm repair (FEVAR) is an evolving technique to treat juxtarenal abdominal aortic aneurysms (AAAs). Catheterization of visceral and renal vessels after the deployment of the fenestrated main body device is often challenging, usually requiring additional fluoroscopy and multiple digital subtraction angiograms. The aim of this study was to assess the clinical utility and accuracy of a computed tomography angiography (CTA)-fluoroscopy image fusion technique in guiding visceral vessel cannulation during FEVAR.

Electromagnetic tracking of flexible robotic catheters enables "assisted navigation" and brings automation to endovascular navigation in an in vitro study.

Objective: Combining three-dimensional (3D) catheter control with electromagnetic (EM) tracking-based navigation significantly reduced fluoroscopy time and improved robotic catheter movement quality in a previous in vitro pilot study. The aim of this study was to expound on previous results and to expand the value of EM tracking with a novel feature, assistednavigation, allowing automatic catheter orientation and semiautomatic vessel cannulation.

Methods: Eighteen users navigated a robotic catheter in an aortic aneurysm phantom using an EM guidewire and a modified 9F robotic catheter with EM sensors at the tip of both leader and sheath.

A robust construction algorithm of the centerline skeleton for complex aortic vascular structure using computational fluid dynamics.

Centerlines of blood vessels are useful tools to make important anatomical measurements (length, diameter, area), which cannot be accurately obtained using 2D images. In this paper a brand new method for centerline extraction of vascular trees is presented. By using computational fluid dynamics (CFD) we are able to obtain a robust and purely functional centerline allowing us to support better measurements than classic purely geometrical-based centerlines.

Robotic-Assisted Inferior Vena Cava Filter Retrieval.

Although anticoagulation remains the mainstay of therapy for patients with venous thromboembolism, guidelines recommend the use of inferior vena cava (IVC) filters in those who fail anticoagulation or have contraindications to its use. Short-term use of filters has proven effective in reducing the rate of pulmonary embolism. However, their extended use is associated with a variety of complications such as thrombosis, filter migration, or caval perforation, thus making a case for timely filter retrieval.

Feasibility of three-dimensional magnetic resonance angiography-fluoroscopy image fusion technique in guiding complex endovascular aortic procedures in patients with renal insufficiency.

Objective: Three-dimensional image fusion of preoperative computed tomography (CT) angiography with fluoroscopy using intraoperative noncontrast cone-beam CT (CBCT) has been shown to improve endovascular procedures by reducing procedure length, radiation dose, and contrast media volume. However, patients with a contraindication to CT angiography (renal insufficiency, iodinated contrast allergy) may not benefit from this image fusion technique. The primary objective of this study was to evaluate the feasibility of magnetic resonance angiography (MRA) and fluoroscopy image fusion using noncontrast CBCT as a guidance tool during complex endovascular aortic procedures, especially in patients with renal insufficiency.

Magnetic resonance venography and three-dimensional image fusion guidance provide a novel paradigm for endovascular recanalization of chronic central venous occlusion.

Objective: Endovascular recanalization is considered first-line therapy for chronic central venous occlusion (CVO). Unlike arteries, in which landmarks such as wall calcifications provide indirect guidance for endovascular navigation, sclerotic veins without known vascular branching patterns impose significant challenges. Therefore, safe wire access through such chronic lesions mostly relies on intuition and experience.

Robotic-Assisted Coil Embolization of Ascending Aortic Pseudoaneurysm.

A 62-year-old man with coronary artery disease and ischemic cardiomyopathy after coronary artery bypass grafting and insertion of a HeartMate II (Thoratec, Pleasanton, CA) left ventricular assist device (LVAD) presented with spontaneous incisional bleeding and an ascending aortic pseudoaneurysm. Aortic angiography revealed an anomalous connection between the pseudoaneurysm and the LVAD conduit. We were able to partially embolize the tract with standard techniques, but the patient returned with repeated bleeding.

Iliac Limb Perigraft Access with Robotic Catheter Assistance for Type 2 Endoleak Embolization.

Retrograde perigraft access to the aneurysmal sac for type 2 endoleak embolization is a relevant alternative to standard transarterial and translumbar approaches. Entering the space between the graft and the iliac artery requires support and pushability, and might be challenging with standard endovascular catheters. We describe the case of a 78-year-old woman with an enlarging aneurysm due to type 2 endoleak, 3 years after EVAR.