0000000000597600
AUTHOR
Olivier Bouchot
Cancer et environnement : expertise collective
Les cancers représentent en France la première cause de mortalité chez les hommes et la deuxième cause chez les femmes et figurent parmi les pathologies pouvant être liées à l’environnement. À la demande de l’Afsset, l’Inserm a réuni un groupe d’experts afin d’établir un bilan des connaissances sur les liens entre l’exposition à des facteurs physiques, chimiques ou biologiques présents dans l’atmosphère, l’eau, les sols ou l’alimentation et neuf types de cancers en augmentation au cours des vingt-cinq dernières années : les cancers du poumon, les mésothéliomes, les hémopathies malignes, les tumeurs cérébrales, les cancers du sein, de l’ovaire, du testicule, de la prostate etde la thyroïde. …
3D segmentation of abdominal aorta from CT-scan and MR images
International audience; We designed a generic method for segmenting the aneurismal sac of an abdominal aortic aneurysm (AAA) both from multi-slice MR and CT-scan examinations. It is a semi-automatic method requiring little human intervention and based on graph cut theory to segment the lumen interface and the aortic wall of AAAs. Our segmentation method works independently on MRI and CT-scan volumes and has been tested on a 44 patient dataset and 10 synthetic images. Segmentation and maximum diameter estimation were compared to manual tracing from 4 experts. An inter-observer study was performed in order to measure the variability range of a human observer. Based on three metrics (the maxim…
Evaluation of the Oxiris Membrane in Cardiogenic Shock Requiring Extracorporeal Membrane Oxygenation Support: Study Protocol for a Single Center, Single-Blind, Randomized Controlled Trial
Background: Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is the rescue treatment proposed to patients with refractory cardiogenic shock. The VA-ECMO implantation promotes inflammation and ischemia-reperfusion injuries through the VA-ECMO flow, causing digestive mucosa barrier disrupture and inducing translocation of bacterial wall components—Lipopolysaccharides (LPS) with further inflammation and circulatory impairment. LPS is a well-studied surrogate indicator of bacterial translocation. Oxiris membrane is a promising and well-tolerated device that can specifically remove LPS. The main study aim is to compare the LPS elimination capacity of Oxiris membrane vs. a non-absorban…
0058 : Low circulating levels of Growth Differentiation Factor 15 (GDF-15) before coronary artery bypass surgery may predict post-operative atrial fibrillation
BackgroundPost-operative atrial fibrillation (POAF) following cardiac surgery has a high prevalence and is associated with considerable morbidity.AimsTo assess the role of GDF-15, a member of the TGFβsuperfamily, as a potential new predictor of POAF after off-pump (OFP) and on-pump (ONP) coronary artery bypass graft (CABG) surgery.MethodsThis observational study recruited the first 50 patients planned for OFP surgery and the first 50 patients planned for ONP surgery. Patients referred for CABG with the following exclusion criteria: age 80 years, previous atrial fibrillation/flutter, previous treatment with Amiodarone, previous cardiac surgery, emergency surgery. Included patients were equip…
A constitutive BCL2 down-regulation aggravates the phenotype of PKD1-mutant-induced polycystic kidney disease
IF 5.340; International audience; The main identified function of BCL2 protein is to prevent cell death by apoptosis. Mice knock-out for Bcl2 demonstrate growth retardation, severe polycystic kidney disease (PKD), gray hair and lymphopenia, and die prematurely after birth. Here, we report a 40-year-old male referred to for abdominal and thoracic aortic dissection with associated aortic root aneurysm, PKD, lymphocytopenia with a history of T cell lymphoblastic lymphoma, white hair since the age of 20, and learning difficulties. PKD, which was also detected in the father and sister, was related to an inherited PKD1 mutation. The combination of PKD with gray hair and lymphocytopenia was also r…
Usefulness and limitations of contractile reserve evaluation in patients with low-flow, low-gradient aortic stenosis eligible for cardiac resynchronization therapy
Aims In low-flow, low-gradient aortic stenosis (LF/LG AS), the assessment of contractile reserve (CR) by dobutamine stress echocardiography (DSE) is recommended for risk stratification and treatment strategy. However, DSE may show limitations in cases of left ventricular dyssynchrony (LVD). The impact of LVD in LF/LG AS, and the feasibility of CRT in this setting have never been evaluated. We aimed to assess: (i) the proportion of LF/LG AS patients with LVD; (ii) the influence of LVD on CR at DSE; and (iii) the effects of CRT in these patients. Methods and results Thirty consecutive patients with LF/LG AS underwent DSE with study of CR. The operative risk for aortic valve replacement (AVR) …
Tracking of blood vessels motion from 4D-flow MRI data
This paper presents a novel approach to track objects from 4D Flow MRI data. A salient feature of the proposed method is that it fully exploits the geometrical and dynamical nature of the information provided by this imaging modality. The underlying idea consists in formulating the tracking problem as a data assimilation problem, in which both position and velocity observations are extracted from the 4D Flow MRI data series. Optimal estate estimation is then performed in a sequential fashion via Kalman filtering. The capabilities of the method are extensively assessed in a numerical study involving synthetic and clinical data.
Procollagen C-Proteinase Enhancer 1 (PCPE-1) is a marker of myocardial fibrosis and impaired cardiac function in a murine model of pressure overload
Abstract(1)AimsProcollagen C-proteinase enhancer 1 (PCPE-1) is an extracellular matrix protein and a major regulator of fibrillar collagen biosynthesis. Previous work has shown that its abundance is often increased in the context of tissue repair and fibrosis. The present study was designed to evaluate its potential as a biomarker of myocardial interstitial fibrosis (MIF), a well-established pathogenic pathway leading to heart failure.(2)Methods and ResultsCardiac fibrosis was induced in rats using an optimized model of chronic pressure overload triggered by angiotensin II and Nω-nitro-L-arginine methyl ester (L-NAME). All treated animals suffered from heart hypertrophy and the increase in …
Acute and delayed toxicity of gemcitabine administered during isolated lung perfusion: a preclinical dose-escalation study in pigs.
BACKGROUND: Colorectal cancer is the third most commonly diagnosed cancer worldwide, with up to 25% of patients presenting with metastases at the time of diagnosis. Despite pulmonary metastasectomy many patients go on to develop pulmonary recurrence, which might be linked to the presence of lung micrometastases. In this setting, the adjuvant administration of high-dose chemotherapy by isolated lung perfusion (ILP) has shown encouraging results. However, the tolerance to and efficacy of modern gemcitabine (GEM)-based chemotherapy regimens during adjuvant ILP remain unknown. We conducted a dose-escalating preclinical study to evaluate the immediate and delayed toxicity of GEM in a pig model t…
Dynamic 4D Blood Flow Representation in the Aorta and Analysis from Cine-MRI in Patients
International audience; Abstract: Natural evolution of aortic disease is characterized by a diameter increase that can result in aortic dissection or rupture. Currently the evaluation of risk of rupture or dissection is based on the size of the aorta. However, this parameter is not always relevant and it appears necessary to define new parameters. In this perspective, 3D velocity imaging acquired with ECG gated velocity-encoded cine-MRI allows the aortic blood flow study. As the acquired images are not directly usable, the present study proposes a 4D-representation Of aortic blood flow in order to optimize the visualization of the particularities of non-laminar flow within the aorta. Image …
Influence of age and sex on aortic distensibility assessed by MRI in healthy subjects
International audience; Abstract: Magnetic resonance imaging (MRI) is particularly well adapted to the evaluation of aortic distensibility. The calculation of this parameter, based on the change in vessel cross-sectional area per unit change in blood pressure, requires precise delineation of the aortic wall on a series of cine-MR images. Firstly, the study consisted in validating a new automatic method to assess aortic elasticity. Secondly, aortic distensibility was studied for the ascending and descending thoracic aortas in 26 healthy subjects. Two homogeneous groups were available to evaluate the influence of sex and age (with an age limit value of 35 years). The automatic postprocessing …
Should aortic stiffness be evaluated in thoracic aortic aneurysm/dissection relatives to prevent risks?
International audience
Segmentation et métrologie des sinus de Valsalva à partir de ciné-IRM
Automatic segmentation of Valsalva sinuses from cine-MRI
Extraction et analyse automatiques des sinus de Valsalva à partir de séquences IRM
MRI appears to be particularly attractive for the study of the Sinuses of Valsalva (SV), however there is no global consensus on their suitable measurements. In this paper, we propose a new method to automatically evaluate the SV from cine-MRI in a cross-sectional orientation. It consists in the extraction of the shape, the detection of relevant points (commissures, cusps and the centre of the SV), the measure of associated distances and in a classification of the SV as bicuspid or tricuspid. Our method was tested on 23 patient examinations and radii calculations were compared with manual processing. The classification of the valve as tricuspid or bicuspid was correct for all the cases. Mor…
Endovascular treatment as first choice in chronic intestinal ischemia.
The purpose of this study was to define the place of endovascular treatment in chronic intestinal ischemia (CII). We report here a series of 19 consecutive patients treated with percutaneous angioplasty of the intestinal arteries. We excluded patients with acute ischemia, from the study. From January 1, 1989 to December 31, 2001, 19 patients with symptomatic CII were treated by endovascular techniques. This study group included 11 men and 8 women with a mean age of 59 years (range 30 to 90 years). The clinical presentation included postprandial pain in 16 patients, weight loss in 14 patients, with a mean weight loss of 7.4 kg (range 0 to 30 kg); and gastroparesis in 2 patients. Stenoses wer…
Temporal Trends in Transcatheter Aortic Valve Replacement in France
Background - Transcatheter aortic valve replacement (TAVR) is standard therapy for patients with severe aortic stenosis who are at high surgical risk. However, national data regarding procedural characteristics and clinical outcomes over time are limited. Objectives - The aim of this study was to assess nationwide performance trends and clinical outcomes of TAVR during a 6-year period. Methods - TAVRs performed in 48 centers across France between January 2013 and December 2015 were prospectively included in the FRANCE TAVI (French Transcatheter Aortic Valve Implantation) registry. Findings were further compared with those reported from the FRANCE 2 (French Aortic National CoreValve and Edwa…
0057 : Preoperative Growth Differentiation Factor 15 (GDF15) as a novel biomarker of acute kidney injury after cardiac bypass surgery
ObjectivePreviously, we demonstrated that preoperative plasma GDF15 levels significantly improved the prognostic value of the EuroSCORE for mortality after cardiac surgery. Despite the strong correlation between GDF15 and renal function, no data are available regarding the potential interest of preoperative GDF15 levels to improve the prediction of acute kidney injury (AKI) after coronary artery bypass grafting (CABG).Design134 patients operated on for CABG of whom 50 underwent offpump surgery at our university hospital were included in this prospective, observational study. Exclusion criteria were age 80 years, previous atrial fibrillation/flutter, previous severe renal failure (estimated …
Comparison of two techniques (in vivo and ex-vivo) for evaluating the elastic properties of the ascending aorta: Prospective cohort study.
Introduction Aneurysms of the ascending aorta (AA) correspond to a dilatation of the ascending aorta that progressively evolves over several years. The main complication of aneurysms of the ascending aorta is type A aortic dissection, which is associated with very high rates of morbidity and mortality. Prophylactic ascending aorta replacement guidelines are currently based on maximal AA diameter. However, this criterion is imperfect. Stretching tests on the aorta carried out ex-vivo make it possible to determine the elastic properties of healthy and aneurysmal aortic fragments (tension test, resistance before rupture). For several years now, cardiac magnetic resonance imaging (MRI) has pro…
Biomechanical study on ascending aortic aneurysms associated with quadricuspid aortic valve
The quadricuspid aortic valve (QAV) is a rare anatomical situation and the biomechanical properties are not well known when it is associated with ascending aortic aneurysms (AsAA). The objective is to find out what is the biomechanical properties in such situation and to compare it with the existing data. In a sixty-three-years-old female (BMI 26,4) with hypertension disease, QAV, AsAA of 52 mm, an aortic valve and ascending aorta replacement were performed. The aortic wall sample was collected within 30 mins after replacement, partitioned related to medial, posterior, lateral, and anterior quadrants. The sample was cut in square size (15 mm × 15 mm, n = 13) with marking the circumferential…
High incidence of venous thrombosis after surgery for abdominal aortic aneurysm
Objective The incidence of venous thromboembolism (VT) after aortic abdominal aneurysm (AAA) surgery is imprecisely reported. On one hand, thromboprophylaxis has improved, on the other hand, AAA patients have become older and/or present worse comorbidities. Herein, we prospectively analyzed the incidence of VT in a continuous series of patients operated on for AAA repair and looked for predictive factors. Materials and Methods Between January 1, 2005, and December, 31, 2006, 193 consecutive patients (177 men and 16 women), mean age 73 (range, 47-93) underwent elective AAA repair, 137 open (71%) and 56 endovascular (29%), in our institution. Thromboprophylaxis consisted of thigh-length compr…
Local ex-vivo evaluation of the biomechanical properties of the ascending aortic aneurysms
Introduction Currently, surgical recommendations for aneurysm of the ascending aorta (AsAA) are based on the maximum diameter of the ascending aorta, but this factor is not reliable. Understanding the biomechanical properties of the aorta could lead to improve the prediction of the development of an AsAA. The aim of this study is to obtain the local patient specific elastic modulus distribution of the AsAA from a biaxial tensile test. Methods Pathologic ascending aortic tissue samples (n = 10) were obtained from patients undergoing elective surgical repair of AsAA ( Table 1 ). All the aortic wall samples were partitioned related to medial, posterior, lateral, and anterior quadrants. Each As…