Patent arterial duct occlusion with two amplatzer duct occluder devices

It is accepted practice to close large patent arterial ducts (PDA) with Amplatzer duct occluder devices, with extremely low rates of residual PDA. This article reports a child who required device closure of PDA with two Amplatzer PDA devices on two separate occasions, despite the first device deployment being a standard placement of an appropriately sized Amplatzer device in the usual position.peer-reviewe

Letter to the Editor: The effect of warfare on the secular trends in sex ratios at birth in Israel, Egypt, and Kuwait over the past 60 years

No Abstract

“Bendy” stents help negotiate hairpin intracardiac curves

Simple transposition of the great arteries (TGA) occurs in 0.2 per 1000 live births. The condition is surgically repaired in the neonatal period by the arterial switch procedure (ASO) sometimes preceded by an atrial septostomy. The ASO involves transecting the great arteries and relocating them to the appropriate ventriculo-arterial (VA) connection with attachment of the disconnected coronary arteries to the aorta. In the process, the attachment of the pulmonary artery to the right ventricle involves the Le Compte manoeuvre and to achieve this the pulmonary arteries must be fully mobilised and sometimes the main pulmonary artery may require patch augmentation as well. Nevertheless, pulmonary artery stenosis (PAS) is one of the potential problems with the ASO. However, with improved surgical techniques, this has dropped from around 15% in the 1980s to less than 3%. Apart from surgical revision when PAS occurs, there are interventional options which include angioplasty and/or stent insertion. The latter is preferred in small children and works well in around 60% but may require repeat procedures. In older patients or when angioplasty fails, stent insertion can be considered. These procedures may involve negotiating tight bends in order to reach the site of stenosis. The passage of non-premounted stents may be problematic in such situations, especially with longer stents and tighter bends as they tend to slip off balloon. We describe several techniques that may facilitate such interventions, and these were utilised in an adolescent patient who had had ASO for TGA in the neonatal period. These included manually giving the mounted stent a slight bend in order to help the balloon-stent assembly negotiate hairpin bends.peer-reviewe

Paediatric wheezy admissions at and around school holiday periods

Objective: To study the influence of school holidays on paediatric admissions with wheezing. Design, setting and patients: Retrospective analysis of all admissions due to wheeze in the paediatric age group. Regional hospital catering for all such admissions, subdivided by age group. Outcome measures: Comparison of hospitalisations due to wheezing before, during and after school holiday periods. Results: Summated admissions showed an increase in admissions over the Christmas period for preschool children, and a decrease for school age children. In Easter and at the start of the summer holidays, admissions decreased in all age groups, except for the late school age group which showed increased admissions in April-May. After the summer holidays, a rise in admissions was noted for all ages. Conclusions: Our findings support the multiphenotypic theory for the precipitation of wheezy attacks, with a changeover from a predominantly viral respiratory trigger to a more atopic form of the disease at around 10 years of age. Prophylaxis during school periods is especially important, and advice leading to prophylaxis dose reduction in the benign summer months should be accompanied by advice to restart adequate prophylaxis medication prior to restarting school.peer-reviewe

Right ventricular outflow tract stenting : effective palliation for Fallot’s tetralogy

Traditionally, the management of infants with Fallot’s tetralogy (TOF) with excessively reduced pulmonary flow and cyanosis has been palliation until or unless complete repair is feasible. Palliation involves a procedure that augments pulmonary flow. Most series recognise two subgroups of patients at high risk even in the current era: the cyanotic neonate/infant with small pulmonary arteries and those with complex anatomical variants of tetralogy and/or significant comorbidities such as additional congenital heart lesions (e.g associated Atrio Ventricular Septal Defect) or other congenital anomalies. There is an argument for palliation of these high-risk groups to allow for future potentially more effective elective repairpeer-reviewe

3 year old with chronic wet cough : Intralobar Bronchopulmonary sequestration

Bronchopulmonary sequestration (BPS) is a rare congenital foregut anomaly of the lung, consisting of nonfunctioning primitive tissue that does not communicate with the healthy tracheobronchial tree. The abnormal segment has its own anomalous systemic blood supply, and typically drains into the pulmonary venous system. It is frequently asymptomatic and may be discovered incidentally. Symptoms may vary, with patients presenting with vague symptoms related to chronic respiratory infection. Early diagnosis and intervention decreases morbidity and mortality. We present a case of intralobar pulmonary sequestration involving the right lower lobe in a male child.peer-reviewe

Coherent forward stimulated Brillouin scattering of a spatially incoherent laser beam in a plasma and its effect on beam spray

A statistical model for forward stimulated Brillouin scattering (FSBS) is developed for a spatially incoherent, monochromatic, laser beam propagating in a plasma. A threshold for the average power in a speckle is found, well below the self-focusing one, above which the laser beam spatial incoherence can not prevent the coherent growth of FSBS. Three-dimensional simulations confirm its existence and reveal the onset of beam spray above it. From these results, we propose a new figure of merit for the control of the propagation through a plasma of a spatially incoherent laser beam.Comment: submitted to PR

Effect of electron heating on self-induced transparency in relativistic intensity laser-plasma interaction

The effective increase of the critical density associated with the interaction of relativistically intense laser pulses with overcritical plasmas, known as self-induced transparency, is revisited for the case of circular polarization. A comparison of particle-in-cell simulations to the predictions of a relativistic cold-fluid model for the transparency threshold demonstrates that kinetic effects, such as electron heating, can lead to a substantial increase of the effective critical density compared to cold-fluid theory. These results are interpreted by a study of separatrices in the single-electron phase space corresponding to dynamics in the stationary fields predicted by the cold-fluid model. It is shown that perturbations due to electron heating exceeding a certain finite threshold can force electrons to escape into the vacuum, leading to laser pulse propagation. The modification of the transparency threshold is linked to the temporal pulse profile, through its effect on electron heating.Comment: 13 pages, 12 figures; fixed some typos and improved discussion of review materia

Mitral valve infective endocarditis following device occlusion of a coronary artery fistula

A three year old girl, with a right coronary artery fistula and signs of a hyperdynamic circulation, underwent uncomplicated closure of the fistula using an occluding device introduced via the femoral arterial route and covered with appropriate antibiotics. Two months later she presented with a persistent fever, signs of infective endocarditis (IE) and embolic phenomena in the left lower limb. Mitral valve endocarditis was confirmed immediately and treated effectively. However, initial ultrasound and doppler did not show the femoral artery thrombo-occlusion that was only confirmed on magnetic resonance angiography (MRA) one month later. This case highlights the usefulness of MRA in diagnosing suspected vessel occlusion in young children, and is in keeping with the latest NICE guidelines that suggest that prophylactic antibiotics do not always prevent IE. Parent and patient education on ‘what to look out for’, combined with careful clinical vigilance is paramount in the early detection of IE with a consequent reduction in morbidity and mortality.peer-reviewe

Random matrix approach in search for weak signals immersed in background noise

We present new, original and alternative method for searching signals coded in noisy data. The method is based on the properties of random matrix eigenvalue spectra. First, we describe general ideas and support them with results of numerical simulations for basic periodic signals immersed in artificial stochastic noise. Then, the main effort is put to examine the strength of a new method in investigation of data content taken from the real astrophysical NAUTILUS detector, searching for the presence of gravitational waves. Our method discovers some previously unknown problems with data aggregation in this experiment. We provide also the results of new method applied to the entire respond signal from ground based detectors in future experimental activities with reduced background noise level. We indicate good performance of our method what makes it a positive predictor for further applications in many areas.Comment: 15 pages, 16 figure