Atresia of the outflow tract of the right ventricle in the presence of an intact ventricular septum poses major problems for surgical management. In the light of known problems, 43 autopsied hearts with this congenital abnormality were evaluated to note the arrangement of the myocardium and the cavity of the right ventricle, the state of the tricuspid valve, the precise substrate for pulmonary atresia, and the presence offistulous communications between the ventricular cavity and the coronary arteries. The specimens could be divided into two groups. The first group (38 hearts) had hypoplasia of the cavity of the right ventricle with mural hypertrophy while the second group (5 hearts) had a dilated right ventricular cavity with thinning of the wall. The larger group could be divided into two subgroups on the basis of the substrate for pulmonary atresia. Twenty hearts had muscular atresia of the right ventricular outflow tract and 18 had a potentially patent outflow tract blocked by an imperforate pulmonary valve. A comparison of these two subgroups revealed that mural hypertrophy and cavitary hypoplasia were more severe in hearts with muscular atresia. The tricuspid valve was hypoplastic and its leaflets were not dysplastic in this group but the leaflets were dysplastic in hearts with valvar pulmonary atresia. Fistulous communications between the ventricular cavity and the coronary arteries were only seen in the cases with muscular atresia. In this series, recognition of muscular pulmonary atresia would have identified those patients with the worst surgical prognosis.

We used pulsed Doppler echocardiography to study the right ventricular diastolic function of29 normal babies and 12 neonates with pulmonary atresia and intact ventricular septum. Eleven patients underwent staged operations of closed pulmonaryvalvotomy followed by either rightventricular outflow reconstruction (n=5) or balloon angioplasty of the pulmonary valve (n=3). In normal babies, the Doppler wave form showed dominant early (E) and separate late active (A) waves of activity, when the heart rate was slow (<100/min). The two waves gradually merged with increasing heart rate, to form a monophasic active wave. Prior to any intervention, all except one of our patients had only a monophasic active right ventricular filling wave over the entire range of heart rates recorded. To quantitate these differences in ventricular filling, we derived 4 diastolic indices from the ratio of: the peak velocity of the early versus the late active wave (EIA); the integral with time of these waves (E/Aarea); the time of diastolic filling relative to the cardiac cycle (TIRR); and the peak diastolic filling velocity relative to the mean filling velocity over the cardiac cycle (Velocity Index). Profiles of the indices against heart rate for both normal controls and patients indicated that only the index of the time of diastolic filling (T/RR) and the Velocity Index were appropriate for our serial comparisons. Thus, for neonates with pulmonary atresia, the index of the time (TIRR) was significantly lower (0.29±0.03 vs 0.43±0.04, p<0.01) and the Velocity Index higher (5.98±0.79 vs 3.98 ±0.31, p<0.001) than those of normal. After valvotomy, but with a poor surgical result, babies continued to have a predominantly monophasic right ventricular filling pattern without significant improvement (p>0.05) of the index of time (T/RR=0.29±0.05) or velocity (5.88±1.17). Babies who underwent a second stage procedure and achieved a final good result had predominantly biphasic right ventricular diastolic filling waves with significant progression (p<0.001) in the index of time (T/RR=0.42±0.03) and velocity (4.09±0.49).

Our experiments using in vivo labeling techniques in the chick embryo heart have demonstrated that the straight tube heart is constituted exclusively by the primordium of the trabeculated portion of the right and left ventricles. There are, therefore, no primitive cardiac cavities. Furthermore, in the stage of looping, two new ventricular components appear, namely, the inlet and the outlet. This new information on the normal development of the heart is important in order to understand both the anatomy of the normal heart and the development of congenital malformations. Due to the fact that the straight tube heart is constituted exclusively by the primordiums of the ventricular trabeculated portions the anatomic identification of the ventricles should be made on the basis of their apical trabeculated regions. The appearance of the components of the inlet and the outlet during the process of looping is the reason for the similarity in the congenital pathology of both regions, namely, a common arterial trunk and atrioventricular septal defect with common orifice. Because the trabeculated portions of the ventricles are the oldest developmental components, they form the basis on which malformations of the inlet or the outlet, or both, are superimposed.

Exercise is of both physical and psychological benefit in children with congenital heart disease, leading to improved cardiovascular fitness and better quality of life. In such children, however, capacity for exercise is often impaired, and there is a risk of exercise-induced mortality or morbidity. We have reviewed the abnormal cardiovascular response to exercise in children with congenital heart defects and postoperative residua, and the role of exercise testing and training in their diagnosis and treatment. Some patients should be excluded absolutely from all but mild regular exercise because of known high risk; for example, those with severe aortic or subaortic stenosis. Other patients should be encouraged to participate in sports without any limitation; for example, those with small left-to-right shunts or mild valvar regurgitation. In many patients strict recommendations cannot be made, and one must consider the individual, the lesion and its hemodynamic implications, and the type and level of exercise contemplated. Children with congenital heart disease should be encouraged to participate in exercise and recreational sport within the limits provided by their cardiovascular defect. Understanding the pathophysiology of these defects, and knowledge of the risk of exercise in certain conditions, will allow the physician to make sensible recommendations for participation in exercise by individual patients.

Between January 1985 and March 1990, 66 children with the tetralogy of Fallot underwent 85 cardiac catheterization procedures. The mean age at first procedure was 2.5 years (range 0.1–;14.4 years) and the mean weight was 10.4 kg ( range 2.4–36.0 kg). Diagnostic cardiac catheterization was performed in 60 procedures and balloon dilatation in 25. Hypercyanotic spells had occurred prior to 24 (28%) of the procedures (all the patients being on propranolol) and a systemic-to-pulmonary arterial shunt had been constructed before 28 (33%) procedures. Of the procedures, 54 (64%) were performed under local and 31(36%) under general anesthesia. The pulmonary trunk was entered antegradely in 52 procedures, retrogradely through a shunt in 6 and not entered in 27. Balloon dilatation was performed under general anesthesia on 25 occasions. No procedure was abandoned because of a cyanotic spell. Nine (11%) spells occurred during 86 procedures, one of the procedures being postponed because ofa spell occurring after premedication, the procedure and not, therefore, continuing to catheterization. Five spells occurred before the catheter was positioned in the heart, 2 spells occurred during catheterization. Of the spells, eight occurred during procedures in children who had not had previous shunts. Antegrade entry into the pulmonary trunk in the group with shunts was associated with no spells compared with 6/38 (18%) in the group not having undergone surgery (p<0.l). In the group not undergoing surgery, when the pulmonary trunk was not entered, 1 (5%) spell occurred during 19 procedures compared with 6/38 (18%) when the pulmonary trunk was entered (p<0.4). The only clinically important factor which significantly influenced the incidence of spells was the use of general anesthesia, which was associated with 6/31 (19%) spells compared with local anesthesia which was associated with 2/54 (4%) spells (p<0.026).

One of the most important contributions of echocardiography to the diagnosis of congenital cardiac malformations is represented by its use in prenatal evaluation. In the present work we discuss the analysis of echocardiographic findings in a preliminary study of the hearts of fetuses in 273 pregnant women. The cases have been divided into three groups. The first group of 169 women was made up of those without a known factor conferring high risk on the pregnancy. The second group of 18 women was comprised of those of suspicions of either arrhythmias or congenitally malformed hearts. The final group of 86 women, consisted of those having had previous children with congenital heart disease. The incidence of pathology in those without risk was 0.5%. In those referred because of suspicion of disease, the incidence was 16.6%, while in those with previous history of children with heart disease, the incidence was 5.8%. Our findings proved the utility of the echocardiogram for the diagnosis of heart malformations prior to birth and confirmed the increased incidence of malformations in fetuses in mothers who had previously produced children with congenital heart disease. The high incidence of cardiac abnormalities in the group referred on the basis of an earlier scan is due to the filter represented by routine echocardiography performed by the obstetricians.

A persistent subcardinal anastomosis was identified as a source of right-to-left shunting in a patient with excessive cyanosis following a modified Fontan procedure. Anomalies of inferior systemic venous return must be defined when a Fontan procedure is performed by direct caval venous anastomosis to the pulmonary arteries, and hepatic venous drainage is left to mix with pulmonary venous return.

Anatomic data are presented of a female abortus with the unusual combination of Ebstein's malformation and atrioventricular septal defect with right isomerism of the atrial appendages, left-hand ventricular topology and discordant ventriculoarterial connection. The common atrioventricular orifice was guarded by an effectively common valve, the right half being guarded by a well-formed three-leaflet valve, but the posterior and left lateral wall of the orifice being deficient of valvar leaflet tissue. The right ventricular inlet was a blind chamber, an imperforate dimple being seen which was surrounded by valvar remnants. The apical trabecular and outlet components of the right ventricle communicated with the left ventricle through an outlet ventricular septal defect in front of the anterosuperior leaflet of the atrioventricular valve, giving the potential clinically for the lesion to be misdiagnosed as double inlet left ventricle.

We describe an unusual heart in which double outlet from the left atrium resulted in atrioventricular connections to a dominant left ventricle and to a left-sided rudimentary right ventricle, while the right atrium also connected to the left ventricle. This produced, in effect, double inlet left ventricle in association with discordant atrioventricular connections. The diagnosis was made by echocardiography and confirmed at post mortem examination.