PubMed Health⌕ Search

Biomedical subjects

E Mousseaux

Publications and source records attributed to E Mousseaux.

At least 19 recordsLinked to original sources

[The potential of magnetic resonance imaging for the surveillance of septal alcohol ablation in hypertrophic obstructive cardiomyopathy. A case report].

We describe here the MRI surveillance of septal alcohol ablation in a case of symptomatic obstructive cardiomyopathy. MRI examinations were performed before, 15 days and 2 months after alcohol ablation using an identical protocol to study the function, regional perfusion and the equilibrium perfusion in order to directly visualize the infarction. MRI seems to be an excellent investigation in the surveillance of such patients, allowing precise quantification of the infarcted zone. The various stages of cellular necrosis in the induced infarct were demonstrated, and the role of remodelling in increasing the functional area of the systolic ejection pathway.

Angioplasty, Balloon, Coronary↗

[Diagnostic value of a two-dimensional echocardiographic score for left ventricular hypertrophy validated by the Imatron CT scan in familial hypertrophic cardiomyopathy].

The aim of this study was to validate a two-dimensional echocardiographic score for left ventricular hypertrophy in familial hypertrophic cardiomyopathy (HCM) by fast CT scan and to study the diagnostic value by an indexed threshold value in affected and genotyped families in comparison with the classical diagnostic method of maximal wall thickness (E max). The study was performed successively in two patient groups with HCM. The echo/CT scan population comprised 26 patients. They underwent echocardiography and Imatron CT scanning. The E max and 2D echo score (sum of the thickness of 4 segments) were measured by echocardiography and compared to the left ventricular mass obtained by the CT method. The 2D echo score was closely correlated to the CT left ventricular mass (r = 0.85) with a higher correlation coefficient than the E max (r = 0.78). The echo/generic population comprised 109 genotyped adults with an identified mutation. The E max and 2D echo score were measured. The genotype was the reference for diagnosis. A theoretical value of the 2D echo score was determined in healthy individuals by a multiple linear regression model of ages, sex and body surface area. A threshold value for abnormality was established after analysis of the ROC. The sensitivity and specificity were 63% and 100% respectively for E max and 73% and 96% respectively for the indexed 2D echo score. The improvement in sensitivity was marked in young adults (< 50 years) with 69% for the indexed 2D echo score versus 54% for E max, p < 0.04. The authors conclude that the indexed 2D score has been validated as an index of hypertrophy by the Imatron CT and has a better diagnostic value than E max, especially in young adults. This echocardiographic criterion could be proposed as an alternative diagnostic sign for screening families.

Adult↗

[Does hypertension need treatment following correction of coarctation in childhood?].

Does hypertension need treatment following correction of coarctation in childhood? The results of the surgical repair of aortic coarctation (CoA) are excellent. Prenatal diagnosis of this defect is made in 40% of the cases and this allowed a reduction of preoperative mortality. Beside these successes, patients who underwent a CoA repair in infancy remain at high risk for resting hypertension (HT) later in life. Indeed, half of the adolescents are hypertensive and 2/3 of the patients around 30 years. This HT is responsible for an increased mortality mostly related to cardiovascular events. Screening for HT and its risk factors is the main objective of the follow-up. Some residual anomalies such as recoarctation or hypoplasia of the horizontal aorta may be treated either by surgery or by interventional catheterisation. Recently, new contributors to hypertension have been identified such as abnormal geometry of the aortic arch or alteration of the mechanical properties of the arterial wall. In a given patient, the co-existence of vascular dysfunction and abnormal geometry of the aortic arch confers a high risk for HT. The indications to treat exercise HT or the type of antihypertensive drug to be given remain unsolved questions. Prevention may rely on substantial modifications of the surgical techniques to optimise the aortic arch geometry. The indications to correct abnormal geometries at high risk without recoarctation are not yet defined. The long-term benefit of either preventive or curative strategies might be difficult to evidence and will probably need the analysis of intermediate markers such as vascular function and left ventricular hypertrophy.

Aortic Coarctation↗

[Cardiac tumors].

Metastases are the most frequent tumors of the heart even though they seldom are recognized. Most primary cardiac tumors are benign. The main role of imaging is to differentiate a cardiac tumor from thrombus and rare pseudotumors: tuberculoma, hydatid cyst. Echocardiography is the fist line imaging technique to detect cardiac tumors, but CT and MRI are useful for further characterization and differential diagnosis. Myxoma of the left atrium is the most frequent benign cardiac tumor. It usually is pedunculated and sometimes calcified. Sarcoma is the most frequent primary malignant tumor and usually presents as a sessile infiltrative tumor. Lymphoma and metastases are usually recognized by the presence of known tumor elsewhere of by characteristic direct contiguous involvement. Diagnosing primary and secondary pericardial tumors often is difficult. Imaging is valuable for diagnosis, characterization, presurgical evaluation and follow-up.

Adult↗

[Noninvasive coronary artery imaging: CT and MR].

The advent of helical multidetector CT has significantly modified several traditional clinical approaches to cardiovascular diagnosis. The current availability of rapid image acquisition has provided the basis for investigating direct imaging in real time of cardiac structures using CT. Application of thin-section submillimetric image acquisitions to three-dimensional (3D) reconstruction algorithms produces 3D data sets from which images of the coronary arteries may be obtained in any anatomic plane. The advantage of the submillimetric isotropic spatial resolution is partly offset by reduced temporal resolution as well as reduced contrast resolution compared to MRI. This lack in contrast sensitivity prevents accurate perfusion imaging and restricts the clinical use to coronary artery imaging. Moreover, the large amount of iodinated contrast medium injected has potential nephrotoxic effects, which can be deleterious if coronary artery angiography must to be performed. On the other hand, MRI has less spatial resolution, and acquisitions must be performed in the plane of each coronary artery because of reduced volume coverage. Both techniques play a role in the non-invasive assessment of coronary artery disease, by providing complementary information already useful in a growing number of clinical situations.

Coronary Angiography↗

Local reconstruction of stenosed sections of artery using multiple MRA acquisitions.

A method for reconstructing magnetic resonance angiography (MRA) volumes from successive acquisitions is described. The method is based on double oblique acquisitions of highly anisotropic MRA volumes, each of which corresponds to reduced k-space filling. These partial k-spaces are then combined to obtain a 3D k-space adapted to the frequency spread of the angiographic image of the stenosis. The SNR-resolution compromise of MRA is thus improved by focusing the acquisition on the most relevant k-space regions. The reconstruction is performed directly in k-space by averaging the partial k-spaces. The feasibility of the method was demonstrated in studies on a Lucite stenosis phantom, on MRAs of carotid arteries using three bolus injections, and on MRAs of renal arteries using a single contrast injection.

Carotid Arteries↗

Ebstein's anomaly: repair based on functional analysis.

OBJECTIVE: 'Classical' repair of Ebstein's anomaly is usually performed with transverse plication of the atrialized chamber. However, the anterior leaflet has restricted motion which is an important factor of the tricuspid valve insufficiency. We studied the long term results of mobilization of the anterior leaflet associated with longitudinal plication of the right ventricule. METHODS: From 1980 to July 2002, 191 patients (mean age 24.4+/-15 years (1-65)) were operated on. Anterior leaflet function was assessed on pre-op echocardiography and on surgical examination. Conservative surgery was possible in 187 patients (98%) and included mobilization of the anterior leaflet, longitudinal plication of the right ventricle and prosthetic annuloplasty in adults. Bidirectional cavo-pulmonary shunt was associated in 60 patients. Four patients had valve replacement. RESULTS: Hospital mortality occurred in 18 patients: 9% (95%CL: 6-15%) due to right ventricle (RV) failure in nine patients. Mean follow-up was 6.4 years (0.07-22). Actuarial survival was 82% at 20 years. Tricuspid valve insufficiency was 1 or 2+ in 80% of the cases. Reoperation occurred in 8% (16 patients). A successful second repair was obtained in ten patients. Electron beam computerized tomography (20 patients) demonstrated improved left ventricle ejection fraction 56-66% (P<0.05). Supraventricular tachycardia and pre-excitation syndromes were reduced from 23 to 5%. CONCLUSION: Conservative surgery is indicated for all symptomatic patients. The incidence of valve repair is high when leaflet mobilization is performed. Valve replacement can be avoided in most cases. Functional and hemodynamic results are excellent.

Adolescent↗

Unilateral renal artery stenosis: perfusion patterns with electron-beam dynamic CT--preliminary experience.

Renal dynamic computed tomographic (CT) data for 16 patients with unilateral renal artery stenosis were compared with those for 12 control subjects. Three patterns of perfusion were distinguished in stenotic kidneys: pattern A, symmetric time-attenuation curves; pattern B, asymmetric time-attenuation curve with similar perfusion; and pattern C, asymmetric time-attenuation curve with impaired perfusion. Additional functional data can be obtained from the initial timing scan in a CT study of unilateral renal artery stenosis.

Adult↗

[Baloon angioplasty with stent implantation in recoarctation of the aorta: an attractive alternative].

The results of transcatheter balloon angioplasty in teenagers and adults with aortic recoarctation are uncertain. Therefore, there is a current trend to prefer a more complex procedure including the implantation of a stent. This study deals with 8 patients aged 7 to 25.3 years (median: 15 years), weighing 20 to 68 kg. (median: 57) and having undergone resection of an aortic coarctation during infancy (24 days to 4 years). All had their lower limb pulses diminished or abolished, elevated blood pressure at rest (and at exercise in the 5 tested patients), and left ventricular hypertrophy. MRI documented the lesion and helped to select seven patients whose stenosis was short and remote enough from the origin of the main aortic collateral. In one case, the decision to stent was taken as an emergent measure to treat an aortic dissection which appeared shortly after balloon dilatation. The effectiveness of the procedure was immediate in all patients with a 50% increase in diameter of the dilated area, total relief of the gradient, drop to normal values of the blood pressure. These good results persisted at follow-up (3-24 months) in 6 patients, with moderate hypertensive rebounds in the last 2. There were 2 technical problems (premature burst of the balloon, asymmetrical inflation of the stent like an "Eiffel Tower") that could finally be overcome and should no longer occur with the new specially designed so-called "BIB" balloons. Would long term follow-up confirm these early results, one should conclude that this method offers an attractive, safe and effective option to surgery for adolescents and adults with late recoarctation of the aorta.

Adolescent↗

[Value of helical CT in Takayasu arteritis].

In the past, the diagnosis and course of Takayasu arteritis were monitored by following angiographic findings, in addition to clinical symptoms and biological tests. More recently, cross-sectional imaging techniques especially Computed Tomography (CT) depicted mural changes in aorta and main vessels in this disease. Within the same acquisition, spiral mode also allows to show luminal changes, similarly to conventional angiography. In addition to its diagnostic value especially in the early phase of the disease, CT seems accurate in the follow-up of treated patients and may be proposed as a therapeutic guide. CT features are presented, according to the stage of the disease and the vessels involved.

Diagnosis, Differential↗

Improved estimation of velocity and flow rate using regularized three-point phase-contrast velocimetry.

We improved the three-point phase-contrast method by regularization of MR velocity data after acquisition of a low velocity-to-noise ratio (VNR) velocity image and a high VNR aliased velocity image. The phase unwrapping algorithm is based on the assumed correlation of the velocity of adjacent flow voxels on the low VNR and the unaliased high VNR images. We used Fourier encoding with eight velocity-encoding gradient steps to obtain reference velocity images of the aorta from five subjects (274 images) and compared them with the phase-contrast and three-point phase-contrast images with and without regularization. The VNR of the regularized velocity image was improved by 9.1 dB and the VNR of the three-point phase-contrast velocity image was improved by 0.7 dB with respect to the low first moment velocity image. Corresponding improvements of 9 dB and 3.7 dB were obtained for the estimations of instantaneous flow rate. Magn Reson Med 44:122-128, 2000.

Adult↗

Estimation of pressure gradients in pulsatile flow from magnetic resonance acceleration measurements.

A method for estimating pressure gradients from MR images is demonstrated. Making the usual assumption that the flowing medium is a Newtonian fluid, and with appropriate boundary conditions, the inertial forces (or acceleration components of the flow) are proportional to the pressure gradients. The technique shown here is based on an evaluation of the inertial forces from Fourier acceleration encoding. This method provides a direct measurement of the total acceleration defined as the sum of the velocity derivative vs. time and the convective acceleration. The technique was experimentally validated by comparing MR and manometer pressure gradient measurements obtained in a pulsatile flow phantom. The results indicate that the MR determination of pressure gradients from an acceleration measurement is feasible with a good correlation with the true measurements (r = 0.97). The feasibility of the method is demonstrated in the aorta of a normal volunteer. Magn Reson Med 44:66-72, 2000.

Adult↗