Training to Perform Ankle-Brachial Index: Systematic Review and Perspectives to Improve Teaching and Learning.

OBJECTIVE: To conduct a systematic review focusing on the impact of training programs on ankle-brachial index (ABI) performance by medical students, doctors and primary care providers. Lower extremity peripheral artery disease (PAD) is a highly prevalent disease affecting ∼202 million people worldwide. ABI is an essential component of medical education because of its ability to diagnose PAD, and as it is a powerful prognostic marker for overall and cardiovascular related mortality. METHODS: A systematic search was conducted (up to May 2015) using Medline, Embase, and Web of Science databases. RESULTS: Five studies have addressed the impact of a training program on ABI performance by either medical students, doctors or primary care providers. All were assigned a low GRADE system quality. The components of the training vary greatly either in substance (what was taught) or in form (duration of the training, and type of support which was used). No consistency was found in the outcome measures. CONCLUSION: According to this systematic review, only few studies, with a low quality rating, have addressed which training program should be performed to provide the best way of teaching how to perform ABI. Future high quality researches are required to define objectively the best training program to facilitate ABI teaching and learning.

Francisella tularensis aortitis.

Francisella tularensis, the agent of tularemia, is a Gram-negative coccobacillus primarily pathogen for animals and occasionally for humans. The clinical manifestations of tularemia include pneumonia, ulceroglandular, oropharyngeal, or typhoidal disease. Rare manifestations are also described, but to our knowledge, we describe here the first case of F. tularensis aortitis in a human. Diagnosis was confirmed by the presence of F. tularensis in blood culture, by the presence of F. tularensis DNA in the aortic biopsy and by specific IgG and IgM responses against the bacteria. The outcome was favorable after surgery and specific antimicrobial therapy.

Treatment of TASC C and D Femoropoliteal Lesions with Paclitaxel eluting Stents: 12 month Results of the STELLA-PTX Registry.

OBJECTIVE: The aim was to evaluate the safety and the efficacy of primary stenting with paclitaxel eluting stents for TASC C and D femoropopliteal lesions. METHODS: Patients with TASC C/D de novo femoropopliteal lesions were treated by implanting paclitaxel eluting stents. Patients were included in a single center registry and prospectively followed by clinical and ultrasound evaluation. X-ray of the stented zone was systematically performed 12 months after implantation. The primary endpoint was primary sustained clinical improvement after 12 months. RESULTS: A total of 45 patients (48 limbs) suffering from claudication (25 limbs) or CLI (23 limbs) were enrolled. Lesions were either TASC C (28 limbs) or TASC D (20 limbs). The mean length of the treated segment was 252 ± 90 mm. The mean number of stents was 2.9 ± 1 (2-5). Mean follow up was 12.7 months. No patient was lost to follow up. At 1 year post procedure, primary and secondary sustained clinical improvements were 56.3 ± 7.4% and 80.1 ± 5.9% respectively. Freedom from target lesion and target extremity revascularization were 63.6% and 90.1%, respectively. Primary and secondary patency rates were 52.5% and 79.6%. One year primary sustained clinical improvement rates for TASC C/D were 63.3 ± 9.2% and 45.6 ± 11.7%, respectively (p = .34). One year primary sustained clinical improvement rates for claudication/CLI patients were 68 ± 9.3% and 41.6 ± 11.1%, respectively (p = .13). The incidence of in stent re-stenosis and in stent thrombosis were 25% and 14%, respectively. The incidence of stent fracture was 12.5% on a limb basis and 9% on a per stent basis. CONCLUSIONS: The paclitaxel eluting stent did not achieve its goal in terms of prevention of in stent re-stenosis for TASC C/D femoropopliteal lesions. It requires frequent re-interventions during the first year to maintain satisfactory clinical results.

Safety and accuracy of endovascular aneurysm repair without pre-operative and intra-operative contrast agent.

BACKGROUND: Severe chronic kidney disease is a major limitation for endovascular aortic aneurysm repair (EVAR). The aim of this study is to assess the safety and accuracy of fusion imaging, when performing EVAR in the absence of pre- and intra-operative contrast agents. METHODS: From October 2013 to February 2014, every patient requiring EVAR and presenting with severe chronic renal impairment underwent a specific pre-operative imaging assessment, based on a non-enhanced CT scan. Centrelines were manually extracted and key points were placed at the landing zones. In house software makes it possible to artificially enhance the contrast between vascular structures and the surrounding tissue, by increasing the values attributed to the vascular structure voxels (500 Hounsfield units). EVAR was performed in a hybrid room (Zeego, Siemens), and the artificially enhanced CT scan was used for the construction of fusion imaging. The 3D vascular volume, together with the centrelines and key points, was overlaid onto the 2D live fluoroscopic image. RESULTS: Six patients (mean age 77.1 years) were treated by EVAR (5 abdominal aneurysms and 1 thoracic aneurysm), using fusion imaging without a contrast agent. The median pre-operative estimated glomerular filtration rate (eGFR) was 17.5 mL/min/1.73 m2. No contrast was used during the procedure. No intra-operative endoleak was observed on the duplex scan. No deterioration was observed in the eGFR at 1 week (eGFR = 21.7, p = .49), nor at 1 month follow up (eGFR = 21, p = .28). The stent graft positioning error was assessed in terms of the difference between the effective and planned landing zones, measured on pre- and post-operative CT scans. The mean error was 1.3 mm at the proximal landing zone, and 6.5 mm at the distal landing zone. CONCLUSION: EVAR without the use of pre-operative and intra-operative contrast agents appears to be safe and accurate for patients with severe chronic kidney disease.

Centerline is not as accurate as outer curvature length to estimate thoracic endograft length.

BACKGROUND: To assess the accuracy of the aortic outer curvature length for thoracic endograft planning. METHODS: Seventy-four patients (58 men, 66.4 ± 14 years) who underwent thoracic endovascular aortic repair between 2009 and 2011 treated with a Cook Medical endograft were enrolled in this retrospective study. Immediate postoperative CT scans were analysed using EndoSize software. Three vessel lengths were computed between two fixed landmarks placed at each end of the endograft: the straightline (axial) length, the centerline length and the outer curvature length. A tortuosity index was defined as the ratio of the centerline length/straightline length. A Student t test and a Pearson correlation coefficient were used to examine the results. RESULTS: We found a significant difference between the centerline length (135.4 ± 24 mm) and that of the endograft (160 ± 29 mm) (p < .0001). This difference correlates with the tortuosity index (r = .818, p < .0001), the endograft length (r = .587, p < .0001), and the diameter of the endograft (r = .53, p < .0001). However, the outer curvature length (161.3 ± 29 mm) and the endograft length (160 ± 29 mm) were similar (p = .792). CONCLUSION: The outer curvature length more accurately reflects that of the deployed endograft and may prove more accurate than centerlines in planning thoracic endografts.

A parametric study assessing Implicit Solver limits for a generic FEM Simulation of PTA without stent deployment.

This study focuses on the robustness of a generic Finite Element Model (FEM) of Percutaneous Transluminal Angioplasty (PTA) procedure with permanent set. The influence of three different parameters on simulation robustness were investigated: the stenosis percent, the stenosis offset and the arterial caliber. Five arterial calibers are modeled by adapting the ratio between the inner diameter and the wall thickness. Overall, forty configurations were tested with the same simulation settings and boundary conditions. Results shows convergence issues caused by excessive deformations of elements for stenosis above 65% blockage. Moreover, an increasing stenosis offset tends to decrease convergence. Simulation of PTA on small calibers and large calibers are less robust than intermediate e.g., iliac calibers.Clinical Relevance- PTA can benefit from numerical tools to improve the procedure outcomes. A FEM simulation of PTA without stent deployment can predict the permanent strain induced by this surgery for various configurations. However, robustness of the simulation is required to consider its transfer to clinics. This work aims to determine the robustness boundaries of an implicit solver for PTA simulation. It shows that an implicit solver is robust for all artery calibers with a stenosis below 50% blockage. Moreover medium-caliber arteries exhibit better robustness with converging solutions for stenosis reaching 60% blockage.

The influence of angioplasty balloon sizing on acute post-procedural outcomes: a Finite Element Analysis.

Atherosclerosis is one of the most common vascular pathologies in the world. Among the most commonly performed endovascular treatments, percutaneous transluminal angioplasty (PTA) has been showing significantly positive clinical outcomes. Due to the complex geometries, material properties and interactions that characterize PTA procedures, finite element analyses of acute angioplasty balloon deployment are limited. In this work, finite element method (FEM) was used to simulate the inflation and deflation of a semi-compliant balloon within the 3D model of a stenosed artery with two different plaque types (lipid and calcified). Self-defined constitutive models for the balloon and the plaque were developed based on experimental and literature data respectively. Balloon deployment was simulated at three different inflation pressures (10, 12 and 14 atm) within the two plaque types. Balloon sizing influence on the arterial elastic recoil obtained immediately after PTA was then investigated. The simulated results show that calcified plaques may lead to higher elastic recoil ratios compared to lipid stenosis, when the same balloon inflation pressures are applied. Also, elastic recoil increases for higher balloon inflation pressure independent of the plaque type. These findings open the way for a data-driven assessment of angioplasty balloon sizing selection and clinical procedures optimization.Clinical Relevance- The FE model developed in this work aims at providing quantitative evaluation of recoil after balloon angioplasty. It may be useful for both manufacturers and clinicians to improve efficiency of angioplasty balloon device design and sizing selection with respect to plaque geometry and constitution, consequently enhancing clinical outcomes.

[Paradoxical embolism and ischemia of the digestive tract]. / Embolie paradoxale et ischémie digestive.

The digestive tract is an uncommon location of acute ischemia, especially when caused paradoxical embolism. We report the case of a 69-year-old patient initially hospitalized for a acute ischemia of the upper limb. Physical examination and complementary tests enabled the diagnosis of paradoxical embolism with bilateral pulmonary embolism leading to elevated pressure in the pulmonary arteries, which opened the oval foramen. The patient also presented ischemia involving the digestive trunks, the upper limb and the kidneys. Rapid diagnosis is a major challenge in this condition controlling the prognosis of this uncommon disease.

Patient-Specific Finite-Element Simulation of the Insertion of Guidewire During an EVAR Procedure: Guidewire Position Prediction Validation on 28 Cases.

OBJECTIVE: Validation of a numerical method to compute arterial deformations under the insertion of an "extra-siff" guidewire during Endovascular Repair of Abdominal Aortic Aneurysm. METHODS: We propose the validation of a previously developed simulation method. The model is calibrated using anatomical hypothesis and intraoperative observations. Simulation results are blindly evaluated against 3-D imaging data acquired during the surgical procedure on 28 patients, based on the predicted position of the intraoperative guidewire. RESULTS: Simulation was successfully conducted on the 28 patients. The mean position error given by the Modified Hausdorff Distance for the 28 cases was 3.8 ± 1.9 mm, which demonstrates very good results for most of the cases. CONCLUSION: The work reported here shows that numerical simulation can predict some rather large variations in the vascular geometry due to tools insertion, for a wide variety of aorto-iliac morphologies. This is a new step toward clinically applicable mechanical simulation. SIGNIFICANCE: Validation on 3-D intraoperative data on a large number of cases-robustness on adverse anatomies.

A versatile intensity-based 3D/2D rigid registration compatible with mobile C-arm for endovascular treatment of abdominal aortic aneurysm.

PURPOSE: Augmented reality-assisted surgery requires prior registration between preoperative and intraoperative data. In the context of the endovascular aneurysm repair (EVAR) of abdominal aortic aneurysm, no satisfactory solution exists at present for clinical use, in particular in the case of use with a mobile C-arm. The difficulties stem in particular from the diversity of intraoperative images, table movements and changes of C-arm pose. METHODS: We propose a fast and versatile 3D/2D registration method compatible with mobile C-arm that can be easily repeated during an EVAR procedure. Applicable to both vascular and bone structures, our approach is based on an optimization by reduced exhaustive search involving a multi-resolution scheme and a decomposition of the transformation to reduce calculation time. RESULTS: Registration was performed between the preoperative CT-scan and fluoroscopic images for a group of 26 patients in order to confront our method in real conditions of use. The evaluation was completed by also performing registration between an intraoperative CBCT volume and fluoroscopic images for a group of 6 patients to compare registration results with reference transformations. The experimental results show that our approach allows obtaining accuracy of the order of 0.5 mm, a computation time of [Formula: see text] and a higher rate of success in comparison with a classical optimization method. When integrated in an augmented reality navigation system, our approach shows that it is compatible with clinical workflow. CONCLUSION: We presented a versatile 3D/2D rigid registration applicable to all intraoperative scenes and usable to guide an EVAR procedure by augmented reality.

[Peripheral artery disease in patients younger than 50 years old: Which etiology?]. / Artériopathies périphériques juvéniles.

Peripheral arterial disease (PAD) encompasses disease of all arteries of the body except the coronary arteries. The main etiology whatever the patient's age is atherosclerosis. Different etiologies can induce PAD especially when patients are younger than 50 years old and have no cardiovascular risk factors (smoking, hypertension, diabetes…). PAD that appears before 50 years old can be named juvenile PAD (JPAD) although there is no consensus about the definition. The aim of this work is to present the different etiologies of JPAD according to their hereditary, acquired or mixed origins. The following hereditary causes are addressed: Marfan syndrome, Ehlers-Danlos syndrome, homocystinuria, pseudoxanthoma elasticum, osteogenesis imperfecta "mid-aortic" syndrome. Among the acquired etiologies, inflammatory JPADs without extravascular signs such as atherosclerosis and Buerger's disease, inflammatory JPADs with extravascular signs as Takayasu's disease, Behçet's disease and Cogan's syndrome, JPADs like aortitis, embolic JPADs, iatrogenic JPADs, and mechanical or traumatic JPADs are described. Finally, mixed origins as thrombotic disease and fibromuscular dysplasia are presented. This work will assist clinicians in the diagnosis of JPAD.

State-of-the-art treatment of common femoral artery disease.

Atherosclerotic common femoral artery (CFA) disease is a well-known and frequent cause of symptomatic peripheral artery disease (PAD). Not so long ago, surgical treatment was considered the gold standard and the main treatment option. Therapeutic advances have, however, provided a wide and suitable armamentarium. These advances concern medical treatment and the direct treatment of lesions by open surgery or endovascular treatment. The aim of this manuscript was to summarize therapeutic updates and to describe the current endovascular and open surgical procedures used to treat common femoral artery disease.