Florida is the fourth largest state in the United States of America. “Heart Week in Florida” is a joint collaborative project sponsored by The Children's Hospital of Philadelphia and The Congenital Heart Institute of Florida. The cardiac programme of Children's Hospital of Philadelphia is one of the largest and most prestigious comprehensive cardiac programmes in the world. The Congenital Heart Institute of Florida is the largest programme providing services for patients with congenital cardiac disease in Florida. Both institutions are very grateful to Bob Anderson, and the team at Cardiology in the Young, for their support of “Heart Week in Florida”, and for the opportunity to publish this Supplement. Bob Anderson was a valued faculty member, and tremendous supporter, of both the fourth annual International Symposium on Congenital Heart Disease held at All Children's Hospital and University of South Florida, and the seventh annual Update on Pediatric Cardiovascular Disease organized by Children's Hospital of Philadelphia.

Whatever the specific anatomy, the Fontan circulation, be it created directly or subsequent to a bi-directional cavopulmonary anastomosis, transforms completely the pattern of circulation of the blood. In essence, it converts a network of circulations in parallel into one in series. The haemodynamic consequences are numerous. The most important and direct among them is, perhaps, the increase in afterload, as well as the reduction in preload, for the systemic ventricle. From the clinical point of view, the most immediate and relevant implication is the amelioration of cyanosis, this being the consequence of removing the common mixing of systemic and pulmonary venous blood within the heart.

The normal heart possesses two ventriculo-arterial junctions – one for the aortic valve, and the other for the pulmonary valve. In the normal heart, these pulmonary and aortic roots are discrete and separate structures, the subpulmonary infundibulum being a free-standing muscular sleeve, separated by extracardiac space from the outflow tract of the left ventricle. When considering the congenital malformations that can distort these outflow tracts, it is conventional to categorise them as existing at subvalvar, valvar, and supravalvar levels. Such an approach, however, ignores the fact the valvar leaflets themselves extend through a significant length of the outflow tracts, with so-called supravalvar stenosis almost always involving the sinutubular junction, this being an integral part of the mechanism that normally ensures competent valvar closure. When considering the lesions that involve abnormally structured outflow tracts, these are best analysed by recognising the different features of the ventriculo-arterial junctions, namely the way the arterial trunks are joined to their underlying ventricles, the interrelationships of the trunks one to the other, and the arrangement of the supporting ventricular structures. In this review, we will show how knowledge of the arrangement of the normal junctions provides the necessary scaffold for logical analysis of all the lesions that can afflict the outflow tracts, be they otherwise normally or abnormally structured.

At first sight, the venous and arterial poles of the heart seem to belong to a single structure. This feature is demonstrated by the continuity seen in the fibrous skeleton between the leaflets of the aortic valve with those of both the mitral and tricuspid valves. Moreover, the orifice of the aortic valve is deeply wedged in between the fibrous annuluses supporting the two atrioventricular valves.

Background: Modified ultrafiltration has been shown to reverse haemodilution and improve ventricular function following cardiopulmonary bypass. There has been concern, however, about the safety and efficacy of modified ultrafiltration after the first stage of Norwood reconstruction for palliation of neonates with hypoplasia of the left heart and its variants. Methods: We reviewed the intraoperative course of all patients undergoing the first stage of Norwood reconstruction between September 1, 2000, and August 31, 2002. Results: The first stage of reconstruction was performed in 99 neonates, 78 with classical hypoplasia of the left heart, and 21 with variants. Mean weight at surgery was 3.1 plus or minus 0.7 kilograms. Genetic syndromes, weight less than or equal to 2.5 kilograms, and/or major additional cardiac or non-cardiac anomalies, were present in 44 patients. We deemed these patients to constitute the group at high risk. A modified Blalock–Taussig shunt was utilized in 95 patients, and a conduit from the right ventricle to the pulmonary arteries in 4. Deep hypothermic circulatory arrest was used in all patients for a mean period of 45 minutes, plus or minus 15 minutes. Total support time on cardiopulmonary bypass plus deep hypothermic circulatory arrest was 100 minutes plus or minus 26 minutes. Modified ultrafiltration was performed in all patients. The mean duration of modified ultrafiltration was 10 plus or minus 2 minutes, and the total volume of filtrate removed was 104 plus or minus 29 millilitres per kilogram. There were no complications from modified ultrafiltration, and no patient required discontinuation of modified ultrafiltration for haemodynamic instability. During modified ultrafiltration, the haematocrit increased from 31 percent plus or minus 4 to 46 percent plus or minus 6. Heart rate decreased from 170 plus or minus 17 beats per minute to 158 plus or minus 16 beats per minute. Systolic blood pressure increased from 57 plus or minus 12 to 63 plus or minus 13 millimetres of mercury, and diastolic blood pressure from 30 plus or minus 8 to 35 plus or minus 7 millimetres of mercury. All these values are significant at a p value of less than 0.0001. Hospital morality in the patients at low risk was 3 of 55 (5.5 percent), but was 12 of 44 (27.3 percent) in the patients deemed to be at high-risk. Conclusions: Modified ultrafiltration is safe procedure following the first stage of Norwood reconstruction, with improvement in all haemodynamic parameters measured. Modified ultrafiltration is an additional incremental strategy, which may contribute to the overall improvement in outcome following surgical palliation of patients with hypoplasia of the left heart or its variants.

Background: Definition of normative data of the great arteries from neonatal to adult ages may aid in assessment of the growth of cardiovascular structures, thus guiding the timing and type of intervention in patients with congenital cardiac disease. Methods: We calculated the cross-sectional areas of the arterial roots at the basal attachment of the valvar leaflets, the sinuses, and standardized distal sites using cineangiograms of 59 normal children and adolescents with mean age of 5.4 plus or minus 4.7 years and a range from 0.1 to 16 years, the children having a mean weight of 21.2 plus or minus 15.7 kilograms, with a range from 2.2 to 68 kilograms, and mean height of 108 plus or minus 35 centimetres, with a range from 43 to 184 centimetres. Values at each site were calculated averaging end-diastolic and end-systolic measurements, and indexed to body surface area. Results are expressed as the mean plus or minus the standard deviation. Results: The diameter of the aortic root at the basal attachment of the leaflets was 249 plus or minus 26, the midpoint of the sinuses 379 plus or minus 59, the sinutubular junction 290 plus or minus 58, the isthmus 158 plus or minus 36, the postisthmic region 152 plus or minus 33, and the descending aorta at the level of diaphragm 130 plus or minus 18 millimetres squared per metre squared. The pulmonary root measured at the basal attachment of the leaflets was 253 plus or minus 28, the midpoint of the sinuses 352 plus or minus 58, the sinutubular junction 293 plus or minus 58, the right pulmonary artery 176 plus or minus 25, the left pulmonary artery 153 plus or minus 20, and sum of right and left pulmonary arteries 330 plus or minus 37 millimetres squared per metre squared. All indexes were consistent over a wide range for body surface areas. Conclusions: Definition of normative data of the great vessels may aid in the evaluation of congenital or acquired abnormalities, serving as guidelines for intervention during medical or surgical management and follow-up.

Treatment in heart failure could be guided by additional non-clinical measures, such as neurohumoral levels. Variability in heart rate is known to reflect neurohumoral stimulation. With this in mind, we sought to assess retrospectively the variability in heart rate to guide the treatment of infants in heart failure.

We analysed retrospectively the data from 20 infants with a significant left-to-right shunt. All were unsuitable for cardiac surgery or interventional therapy at the time the treatment had commenced. None of the infants improved while receiving diuretics, spironolactone, and digoxin alone, but improved after the addition of propanolol or metoprolol. None of the infants had problems during or after the subsequent operation. Parasympathetic activity reflected by parameters of variability in heart rate, such as the square root of adjacent RR-intervals, and the amount of adjacent RR-intervals greater than 50 milliseconds, improved in nearly all infants during beta blockade. On the other hand, parameters of variability in heart rate reflecting sympathetic activity did not change. Parasympathetic activity reflected the clinical state of nearly all the infants. These parameters, therefore, seem to be a good non-clinical parameter, showing the optimal treatment for heart failure in an ambulatory setting.

In the normal heart, the morphologically right ventricle supports the pulmonary trunk. The key to echocardiographic evaluation of the junction between these structures is to understand not only the arrangement of the pulmonary valve, but also the complete muscular infundibulum that supports the valvar leaflets, lifting the valvar complex away from the base of the ventricular mass. As explained in the previous review,1 it is the presence of this free-standing muscular infundibular sleeve that makes it possible for the surgeon to remove the pulmonary valve for use as an allograft in the Ross procedure.2 In this review, we will address the echocardiographic features of the junction, considering primarily the situation in which the morphologically right ventricle supports the pulmonary trunk, but making comparisons with the abnormal arrangements in which either the aorta, or both arterial trunks, arise from the right ventricle. As we will see, the basic arrangement of the free-standing complete muscular infundibulum, or conus, is preserved with these abnormal arrangements, but there can be variation depending on the precise arrangement of the inner heart curvature, or ventriculo-infundibular fold, and the morphology can be further changed depending on the relationship of the arterial trunks themselves. The key to analysis, therefore, and also to accurate description, is to analyse separately the way in which the arterial trunks are joined to the ventricular mass, the relationships of the trunks one to the other, and the precise structure of the supporting right ventricular outflow tract, or outflow tracts in the setting of double outlet connection. If each of these features is then described in its own right, avoiding the temptation to make inferences regarding one feature from knowledge of another, then it is possible to avoid many of the persisting controversies relating to nomenclature.

Patients with a functionally univentricular circulation represent a challenge for both surgeons and cardiologists. In this introductory paper, we aim to describe the variability in cardiac phenotype amongst these patients, and to review how function might relate to anatomy.