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In man, the Y chromosome spans approximately 58 million base pairs and represents just 1% of the total DNA in a male cell.1 Sex is determined in the SRY locus on the Y chromosome. During the formation of gametes, chromosomal crossover between homologous chromosomes during the meiotic division results in genetic diversity. Genetic recombination can also repair damaged genes. Recombinations between the two X chromosomes for self-repair is possible in females but is not possible for the Y chromosome since this chromosome is present in isolation in the male. This has led to the hypothesis that the Y chromosome may one day become extinct due to cumulative and unrepaired damage.2 This has occurred, for example, in the Transcaucasian mole vole which does not have an SRY gene or Y chromosome, with both sexes possessing a XO sex chromosome only. Indeed, in this species, sex determining genes are found on a different chromosome. In Turner syndrome, the affected individual has one X chromosome, with an absent sex chromosome. It had been assumed that the missing chromosome is an X chromosome, but this may not be the case. It is now proposed that this condition may be caused by a paternal unstable isodicentric Y during the formation of germ cells, such that the Y chromosome is the missing chromosome.5,6 Evidence for this includes the absence of an increased incidence of Turner’s syndrome with increasing maternal age, along with the fact that the X chromosomes present in Turner syndrome are 74% maternally derived. Here the authors present a case of mosaic Turner’s syndrome, i.e. a patient with two cell lines, 45X and the other with 46 chromosomes, one of which was an isodicentric Y chromosome. Fluorescence in situ hybridization (FISH) showed that the SRY locus is present on the Y chromosome in this phenotypical female patient., peer-reviewed

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-reviewed

This article includes a case report of women with coarctation of the aorta which was treated with stent implantation., peer-reviewed

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-reviewed

Arterial cannulation is a common procedure for diagnostic as well as interventional catheterisation. The incidence of arterial damage varies from around 1% to 45 % depending on the size of the patient, size of catheters used, repeat procedures, preexisting vascular disease and whether the procedure was interventional as opposed to diagnostic (twelve times higher risk with intervention). The absence of a pulse following catheterisation can result from spasm, local thrombus formation, formation of a flap of endothelium, dissection or avulsion of the artery. In order to minimize the risks of arterial damage the following factors may help: a clean puncture, small French catheters, tapered well-fitting introducer sheaths, a short procedure time and administration of heparin (50 to 100 units/kg with further dose/s if the procedure lasts more than 75 minutes)., peer-reviewed

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-reviewed

Significant atrial septal defects (ASD) are closed, surgically or through a transcatheter device, in order to avoid pulmonary hypertension in late life. A patent foramen ovale (PFO) may need to be closed because of transient shunt reversal resulting in transient ischaemic events or stroke. We report the Maltese experience to date in transcatheter closure of these defects. A total of 46 ASDs and 51 PFOs have been successfully closed at our unit (total 97), with very low complication rates, rates that compare very favourably with results from larger international centres., peer-reviewed

Transcatheter closure of patent ductus arteriosus is now a well established therapeutic option. In this paper, we illustrate step by step the technique of Flipper coil closure of small (, peer-reviewed

Ventricular septal defects (VSD) consist of deficiencies of the wall separating the two ventricles. VSDs are the commonest congenital cardiac defects. Small VSDs rarely require intervention, however, larger defects cause ventricular volume overload with or without heart failure or pulmonary hypertension and may, therefore, require closure. Traditionally, closure has been an open heart surgical procedure. In recent years, various devices have been developed to close a wide variety of cardiac defects including atrial septal defects and patent arterial ducts through transcatheter interventional techniques. Recently, AGA Medical Corporation have introduced a range of Amplatzer VSD occluders which include specific devices for perimembranous (PM), muscular and post myocardial infarction (MI) VSDs. Atrial septal defect and patent foramen ovale closure has been carried out at St. Luke's Hospital in Malta for the past three years. This year, for the first time, we have closed three VSDs in three individuals; two children with large perimembranous defects and an elderly gentleman with a large post-MI VSD. This paper will discuss this technique and initial results., peer-reviewed

This paper summarises the rationale behind cardiac catheter assessment prior to surgical completion of the Fontan circulation in hearts with univentricular pathology., peer-reviewed

This article presents a patient who had transcatheter closure of a low atrial septal defect which was overlooked during surgical closure of a secundum atrial septal defect. The residual defect was detected during ablation for atrial flutter, and was closed successfully during the same procedure with an Amplatzer atrial septal occluder (ASO) device., peer-reviewed

This article presents two patients who had delayed transcatheter closure of secundum atrial septal defects for persistent cyanosis after surgical repair of severe pulmonary stenosis. The defects (two in one patient) were closed uneventfully and successfully with Amplatzer ASO devices, with significant improvement in oxygen saturation. The staged approach and the complementary role of surgery and intervention are discussed., peer-reviewed

Balloon aortic valvuloplasty is now the treatment of choice for congenital aortic stenosis. Balloon stability may be difficult to achieve and this may result in a suboptimal result or even valve damage. We describe the technique of rapid ventricular pacing as a safe and effective option for achieving balloon stability during aortic valvuloplasty., peer-reviewed

Scimitar syndrome is a form of partial anomalous pulmonary venous drainage that is dramatically visible on plain chest radiography (CXR). In these individuals the entire venous drainage from the right lung enters a single anomalous large vein that descends to the inferior vena cava. This descending vein is visible on CXR as a curvilinear density along the right heart border and resembles the curved Turkish sword that gives the condition its name. Scimitar syndrome forms part of the large spectrum of associated conditions known as venolobar syndrome. These include right lung hypoplasia or sequestered segments of right lung, congenital heart disease and various others. We report the case of a young woman who presented incidentally, with a murmur, at 16 years of age. Full investigation including angiography showed a large atrial septal defect with right heart dilation and scimitar syndrome. She underwent surgical correction with uneventful and complete correction by baffling of the scimitar vein from its entry into the inferior vena to the left atrium through the enlarged atrial septal defect., peer-reviewed

Transcatheter closure of atrial septal defects and patent foramen ovale is now a well established therapeutic option. In this paper, we illustrate, step by step, the technique of Amplatzer ASO closure of these defects., peer-reviewed