Atresia of the aortic valve is usually associated with hypoplasia of the mitral valve and the left ventricle. In very rare cases, a ventricular septal defect may be associated with aortic atresia, when left ventricle and mitral valve are normal-sized, due to the presence of an outflow for the left ventricle through the ventricular septal defect. We present the multi-modality imaging findings of an adolescent girl who presented with breathlessness and was later found to have aortic valvar atresia with a normal-sized left ventricle.

Gemella is a genus of Gram-positive bacteria found in the digestive tract of humans. They rarely cause systemic illness but have been recently implicated in several serious infections. We report infective endocarditis caused by Gemella bergeri in a 23-year-old with a bicuspid aortic valve status post-intervention in infancy.

This December Issue of Cardiology in the Young represents the 12th annual publication generated from the two meetings that compose “HeartWeek in Florida”. “HeartWeek in Florida”, the joint collaborative project sponsored by the Cardiac Center at the Children’s Hospital of Philadelphia, Pennsylvania, together with Johns Hopkins All Children’s Heart Institute of Saint Petersburg, Florida, averages over 1000 attendees every year and is now recognised as one of the major planks of continuing medical and nursing education for those working in the fields of diagnosis and treatment of cardiac disease in the foetus, neonate, infant, child, and adult. “HeartWeek in Florida” combines the International Symposium on Congenital Heart Disease, organised by All Children’s Hospital and Johns Hopkins Medicine and entering its 15th year, with the Annual Postgraduate Course in Pediatric Cardiovascular Disease, organised by The Children’s Hospital of Philadelphia and entering its 18th year. This December, 2014 Issue of Cardiology in the Young features highlights of Johns Hopkins All Children’s Heart Institute’s 14th Annual International Symposium on Congenital Heart Disease, which was held at the Renaissance Vinoy Resort & Golf Club, Saint Petersburg, Florida, from 15–18 February, 2014. This Symposium was co-sponsored by The American Association for Thoracic Surgery (AATS) and had as its special focus “Diseases of the Cardiac Valves from the Fetus to the Adult”. We acknowledge the tremendous contributions made to paediatric and congenital cardiac care by Duke Cameron and Joel Brenner, and therefore we dedicate this December, 2014 HeartWeek Issue of Cardiology in the Young to them. Duke Cameron is Professor of Surgery at Johns Hopkins University and Cardiac Surgeon-in-Charge at The Johns Hopkins Hospital. Joel Brenner is Professor of Pediatrics at Johns Hopkins University and Director of the Taussig Heart Center at Bloomberg Children’s Center, The Johns Hopkins Hospital. Together, Joel and Duke lead the proud paediatric and congenital cardiac programme at The Johns Hopkins Hospital.

Advances made in the understanding of the molecular biology of the cardiac valves have been truly spectacular. Not all of those investigating these aspects, however, have an appropriate understanding of the underlying anatomy. Partly, this reflects problems in describing the components of the various valves, a difficulty also emphasised by surgeons who repair or replace the valves. In this review, we describe briefly the overall anatomy of the cardiac valves, pointing to their similarities and differences. We then suggest that uniform terms can be developed to account for the components of the valves, treating them as complexes that guard the atrioventricular and ventriculo-arterial junctions. The atrioventricular valvar complex is made up of an annulus, leaflets, tendinous cords, and papillary muscles. The tension apparatus is required to hold the leaflets together against the force of ventricular systole. The ventriculo-arterial complex is also based on the leaflets, but supported within the valvar sinuses, and limited distally by the sinutubular junction. It is the semilunar nature of the leaflets that underscores their snug closure during ventricular diastole. The complexes thus defined can be separated to produce paired valves in the normal arrangement, or to produce common valves in the congenitally malformed hearts. Knowledge of development now permits accurate inferences to be made regarding the origin of the various components, and their relevance to valvar disease. The valvar leaflets are developed from the endocardial cushions formed in the atrioventricular canal and the outflow tract by a process of endothelial-to-mesenchymal transformation. The papillary muscles of the atrioventricular valves are then derived from the trabecular layer of the developing ventricular walls, whereas the sinuses of the ventriculo-arterial valves are formed by additional growth of the non-myocardial tissues, concomitant with excavation of the outflow cushions to form the leaflets.

A 2-year-old boy developed fibromyxoid excrescence of the aortic valve 2 years after balloon dilatation for simple coarctation. Transthoracic echocardiography showed a mobile mass on the non-coronary cusp of the aortic valve. Definitive diagnosis was achieved after operative resection. This pathology was attributed to injury during catheter manipulation. Catheterised patients should be followed up carefully to avoid missing morphological changes.

Human aortic valve is made of thin collagen type tissue. The three leaflets open and close under fluid forces exerted upon them. To simulate the hemodynamic characteristics of the blood flow, ANSYS CFX10.0 software was utilized to analyze the three-dimensional Reynolds-averaged Navier-Stokes equations. With a quasi-steady analysis model, we predict values of the blood velocity and the wall shear stress both over the valve leaflets and the endothelial lining. In addition, investigation on fluid dynamic of a heart valve supposed suffering prolapsed disease has been also conducted, and compared with normal valve. Analysis results highlight that leaflet opening situation and valve geometry affect the shear stress distribution and vortex flow regime. Maximum shear stress takes place near the center of leaflet trailing edge at the very beginning of systolic phase with value of 7.093N/m2. At peak systole, the maximum wall shear stress distributes near the aortic root where jet impingement takes place. Current study also demonstrated the interactive impact between low and high wall shear stress on relation to heart valve disease.

We report replacement of the aortic valve in a patient aged 9 years with mucolipidosis III and severe aortic insufficiency. Histopathology demonstrated abnormalities of the matrix and lysosomal inclusion bodies. As life expectancy increases for patients with lysosomal storage disorders, approaches to intervention for valvar disease become increasingly important.

This paper concentrates on the wall shear stress discussion of implanting bi-leaflet aortic valve and concludes a better valve design. To simulate the haemodynamic characteristics of the blood flow, ANSYS CFX10.0 software was utilized to analyze the three-dimensional Reynolds-averaged Navier-Stokes equations. With a quasi-steady analysis model, we predict values of the blood velocity and the wall shear stress both over the valve leaflets and the endothelial lining. Analysis results highlight that leaflet opening angle and valve geometry affect the shear stress distribution and vortex flow regime. An analysis of haemodynamic study for the St. Jude valve with various openingangles is presented first and the sewing ring geometry change is then recommended. It is found that the wall shear stress decreases significantly after modifying the sewing ring geometry. Maximum shear stress reduces 18.5% compared to that of the original St. Jude model at peak systole. This would ease possible damage of endothelial lining of the aorta.

Wiskott-Aldrich syndrome is a rare X-linked disease, associated with immunodeficiency, infections, thrombocytopaenia, and eczema. Aortitis and formation of aneurysms have also been described. We describe here our experience with a 7-year-boy with this syndrome. He survived replacement of the aortic root because of an aneurysmal ascending aorta, and subsequent bone marrow transplantation.

The morphology of the aortic valve was studied in 1,022 heart specimens belonging to the collection of the Institute of Pathological Anatomy, University of Padua. Twenty specimens were found to have a unicommissural aortic valve, characterized by the presence of a single leaflet with only one functional commissure; however, the presence of two raphes enabled the recognition of a basically three-sinus arrangement. Age and gender were known in 19 cases: 14 male and five female, mean age nine days. In 19 cases, the unicommissural valve was dysplastic and resulted in a severe congenital aortic valvar stenosis. Only in two hearts was the unicommissural nature of the aortic valve an isolated finding; among the remaining 18, left ventricular fibroelastosis in 11, malformation of the mitral valve in 11, hypoplasia of the left ventricle in eight, ventricular septal defect in four, mitral atresia in three, and subaortic fibrous diaphragm in one. Furthermore, seven (35%) of these 20 unicommissural aortic valves were associated with coarctation of the aorta. Statistical analysis shows that this association is not a random event. Our findings support the hypothesis that the unicommissural aortic valve originates from the early fusion of the three mesenchymal valvar cushions or leaflet primordia. Although the present data do not exclude the possibility that reduction of the blood flow through the aorta during fetal life may play a role in the formation of the unicommissural aortic valve, they rather point in the direction that another etiologic factor, such as an anomalous migration of neural crest cells, may be responsible for the fusion of the valvar cushions.

We studied the morphology of the aortic valves of 1,036 Syrian hamsters belonging to two families subjected to high endogamous pressure. Most (n=955) specimens were examined using a corrosion-cast technique. In the remaining 81 specimens, valvar morphology was assessed by means of a stereomicroscope, and in 18 of these cases a histologic study was also performed. In one of the families, a high proportion (30.5%) of hamsters had aortic valves with two leaflets, the aortic sinuses being oriented ventrodorsally. The percentage of such anomalous valves was found to be positively correlated with the inbreeding coefficient of specimens. In the other family, the occurrence of an aortic valve with two leaflets was a sporadic event. Stereoscopic and histologic observations demonstrated that, in 52 of 63 aortic valves with three leaflets, the ventral commissure between the right and left leaflets was partially fused, while in 10 other cases this commissure was completely fused. In addition, in nine of 18 aortic valves with two leaflets, there was a more or less well-developed raphe located in the ventral aortic sinus, approximately where the true ventral commissure would have been. Our observations suggest the existence of a continuous spectrum of aortic valvar morphology, ranging from a valve with three leaflets and no fusion of the ventral commissure to an aortic valve with two leaflets devoid of any raphe. This spectrum seems to be the result of the interaction of genetic and intrauterine environmental factors. Results of crosses between both related and unrelated hamsters suggest that the observed morphology in individuals is the result of quantitative inheritance.

The role of transesophageal echocardiography in the diagnosis and management of left-sided cardiac valvar disease in children and young adults was assessed in terms of whether additional information (over transthoracic echocardiography) could be obtained, and whether the added information contributed to the better management of the patients. Between January 1991 to August 1992, 27 consecutive patients were studied. Their age ranged from 2.5 to20 years (mean 12.7), with body weights ranging between 12 and 60 kg (mean 35.6). Twelve of the children suffered from atrioventricular valvar disease, 13 had predominant aortic valvar lesions and two had mixed valvar pathologies. Additional information was obtained by transesophageal over that of transthoracic echocardiography in 18 children (67%). Transesophageal echocardiography clarified the etiologies or mechanism of valvar regurgitation in eight and seven children with atrioventricular and aortic pathologies, respectively. The technique correctly diagnosed severe mitral regurgitation underestimated by conventional technique, detected a missed eccentric aortic regurgitant jet and convincingly excluded bacterial vegetations in one case each. The investigation contributed to the better management of three children (11%) by providing information that allowed the appropriate choice of therapy. Transesophageal echocardiography, therefore, is a useful technique for the diagnosis and management of valvar disease of the left heart in children and young adults.

Objective: We reviewed our experience with mechanical valves inserted between 1988 and 2002 in children aged 15 years or younger. Methods: Hospital files were extracted retrospectively. Follow-up was completed by March 2005. Results: Of 41 patients, we inserted a valve in atrioventricular position in 27 children, having a median age of 3.1 years, ranging from 0.4 to 14.5 years, and in aortic position in the remaining 14, having a median age of 13.5 years, and a range from 7.0 to 14.9 years. For the valves inserted in atrioventricular position, the underlying disease was congenital in 23, rheumatic in two, post-endocarditic in one, and Marfan's syndrome in one. Mean follow-up was 7.7 years, with standard deviation of 5.3, giving a total follow-up of 209 patient years. Mortality at 30 days was 7%, and survival was 73% at up to 16 years follow-up. Events related to anticoagulation were seen in 3 patients, corresponding to 1.4% per patient year. In 6 patients (22%), heart block ensued which required implantation of a pacemaker treatment, and 5 patients (19%) had reoperations. For the implantations in aortic position, the underlying disease was congenital in 13, stenosis in 10 and insufficiency in three, and post-endocarditis in one. Mean follow-up was 6.8 years, with standard deviation of 4.6, giving a total of 95 patient years. We lost one patient within 30 days (7.7% mortality), and survival was 77% at up to 13 years follow-up. There were no incidents of thrombosis, nor events related to anticoagulation, but one patient (7%) needed insertion of a pacemaker due to a perioperative heart block, and one (7%) required new valvar replacement. Conclusions: Although preferably avoided, mechanical valves can be implanted in children with an acceptable mortality and morbidity, and good long-term results.