Nicolaas H. van Doesburg

Predictive factors for spontaneous closure of atrial septal defects diagnosed in the first 3 months of life

OBJECTIVES To establish the rate of spontaneous closure of atrial septal defects diagnosed before age 3 months, 101 infants (mean age 26 days) with an interatrial shunt confirmed by Doppler echocardiography were followed up for an average of 265 +/- 190 days. BACKGROUND Even if interatrial shunts in the newborn are frequently encountered, little is known about their natural history. METHODS Defect diameter on two-dimensional echocardiography and width of color flow jet were measured in the subcostal view. Right and left ventricular diameters and atrial septal curvature were also studied. Kaplan-Meier curves were obtained to predict age of spontaneous closure in relation to initial defect diameter. RESULTS There was no significant correlation between the diameter of the atrial septal defect and right ventricular/left ventricular ratio or type of septal curvature (vertical or concave toward the left atrium). The classic predominance of girls over boys was observed only for defects > 5 mm. An overall rate of spontaneous closure of 87% was observed. Frequency and timing of closure were inversely correlated to atrial septal defect diameter: closure occurred in 100% (32 of 32) of defects in group 1 (diameter < 3 mm), 87% of defects (39 of 45) in group 2 (diameter 3 to 5 mm), 80% of defects (16 of 20) in group 3 (diameter 5 to 8 mm). Spontaneous closure did not occur in four patients of group 4 (defect > or = 8 mm) during an average follow-up interval of 417 days (range 294 to 597 days). CONCLUSIONS These results suggest that infants with an atrial septal defect < 3 mm need not be followed up as 100% of these defects will be closed by age 18 months; those with a defect 3 to 5 or 5 to 8 mm should be evaluated by the end of the 12th and the 15th month, respectively, when > 80% of these defects will be closed. An atrial septal defect with a diameter > or = 8 mm may have little chance of closing spontaneously and the possibility of surgical correction should be considered. Defects < 3 mm probably do not constitute a cardiac malformation in light of their natural evolution and gender distribution.

Factors affecting the prognosis of Ebstein's anomaly during fetal life

BACKGROUND The echocardiographic criteria that have been used to evaluate severity of Ebsteins anomaly in utero are the same as those applied after birth. OBJECTIVE The objective of this study was to establish prognostic criteria that take into account the peculiarities of the fetal hemodynamics. METHOD The video recordings of eight fetuses with Ebsteins anomaly were retrospectively reviewed. RESULTS The following indexes had no prognostic significance either on fetal or neonatal outcome: the ratio of functional tricuspid opening over the diameter of the annulus, the degree of displacement of the tricuspid valve opening, and the degree of tricuspid regurgitation. The index of severity (based on the surfaces of right atrium + atrialized right ventricle) and the cardiothoracic ratio had a significant impact only on neonatal survival. The smallest fossa ovalis were found in two fetuses who had hydrops. Fetuses who reached term without problems had higher left ventricular outputs. A positive linear correlation was found between the z score of the left ventricular output and the size of the fossa ovalis (r = 0.81, p < 0.05). CONCLUSION The prognosis of Ebsteins anomaly during fetal life is not influenced by criteria described for postnatal life and may be related to factors that control the volume load of the left ventricle.

Outcome of children with atrial septal defect considered too small for surgical closure

There are few studies providing information on the natural course of hemodynamically insignificant atrial septal defect (ASD). To review the outcome of patients with secundum ASD, we retrospectively reviewed the charts of patients who had initially not been considered for surgical closure after age 1 year, and who had either a follow-up of at least 10 years or documented closure. Thirty patients, 22 females and 8 males, fulfilled our inclusion criteria. Mean age at diagnosis was 1.3 year and mean follow-up duration was 11.5 years. Seventeen patients had spontaneous closure of the ASD at a mean age of 8.4 years. There were 7 asymptomatic patients whose ASD was still patent at the last visit (mean age 14.1 years, mean follow-up 13.2), with defect dimensions on echocardiography ranging from 1 to 6 mm. The remaining 6 patients were considered to require surgical closure on the basis of an apparent increase in size of the ASD and secondary clinical and hemodynamic manifestations. These results (1) confirm that not all secundum ASDs need to be treated surgically because they can still spontaneously close past the age of 5, and (2) suggest that in a minority of cases the size of the defect could increase.

Upper gastrointestinal tract bleeding acquired in a pediatric intensive care unit: Prophylaxis trial with cimetidine

Essai controle en double-insu des effets de la cimetidine (n=19) contre placebo (n=21), chez des enfants de 10 jours a 14 ans. La cimetidine accroit le pH du suc gastrique dans les 3 heures apres la 1ere injection intraveineuse mais ne previent pas les saignements macroscopiques gastro-intertinaux (SMGI) chez les sujets a risque. Le type de prophylaxie est conteste et les transfusions sanguines demeurent indiquees chez les sujets a risque

Echocardiographic and angiographic findings in superior-inferior cardiac ventricles.

The anatomy of superior-inferior ventricles was studied in 17 patients, aged 1 day to 22 years, using echocardiography and angiography. In all patients, the right ventricle was located superiorly and the left ventricle inferiorly. The right ventricular sinus was underdeveloped in 14 of the 17 patients. Conversely, the right ventricular outflow tract was normally developed in all 17 patients. The visceroatrial situs was solitus in all patients, and it was associated with a concordant D-loop in 9 patients and with a discordant L-loop in 8. There was a high incidence of associated transposition of the great arteries (9 patients) or double-outlet right ventricle (5). Segmental combination was unpredictable, D-loop being associated with L-position of the great arteries in 4 of 8 patients and L-loop being associated with D-position of the great arteries in 4 of 9. There were only 3 concordant ventriculoarterial connections. Frequently associated anomalies included ventricular septal defect (17 patients), atrioventricular valve malformations (17) subaortic conus (14) and pulmonary outflow tract stenosis or atresia (11). Criss-cross hearts were present in only 7 patients.

Closure of the ductus arteriosus: determinant factor in the appearance of transient peripheral pulmonary stenosis of the neonate.

We speculated that a relationship may exist between transient peripheral pulmonary stenosis and the closure of the ductus arteriosus. Fifty preterm infants had pulmonary artery and ductal color Doppler flow velocity assessments performed before and after closure of the ductus arteriosus. No flow turbulence or increase in velocity was observed immediately after birth, although a significant discrepancy in size was observed between the main pulmonary artery and its two branches. After closure of the ductus, 15 infants had signs of transient peripheral pulmonary stenosis of the left pulmonary artery in association with a significant decrease of diameter at the origin of the same artery. In all 50 infants, no significant gradient was observed in the right pulmonary artery. We conclude that, at least in the preterm infant, transient peripheral pulmonary stenosis is not present at birth but is an acquired phenomenon closely related to closure of the ductus arteriosus.

Segmental myocardial contractility versus perfusion in Kawasaki disease with coronary arterial aneurysm

The impact of Kawasaki-related coronary injury on the myocardium was evaluated in 13 patients with persistent coronary aneurysm after a follow-up period of 7.92+/-3.97 years (range 1.8 to 14.3). Myocardial segmental perfusion and contractility integrity were assessed by resting and exercise echocardiography and technetium-99 (Tc-99m) sestamibi scan. Eight patients (61.5%) had giant aneurysms (> or = 8 mm) and 9 had multivessel involvement; the mean diameter of the largest aneurysm was 8.6+/-2.5 mm (range 5 to 14). During the acute phase, myocardial infarction occurred in 1 patient and coronary thrombosis in another. At the latest echocardiographic evaluation, the mean aneurysm diameter was 6.8+/-2.4 mm (range 4.5 to 12), there was persistent giant aneurysms in 5 of 8 patients, and 3 of 9 patients had multivessel involvement. Coronary angiography demonstrated stenosis in 7 of 10 patients, with multiple levels in 2. At sestamibi scan, all 13 patients had perfusion anomalies at rest, whereas only 7 had detectable hypokinesia on echocardiography. With exercise, perfusion returned to near normal in 3 patients, improved in 3, remained unchanged in 4, and worsened in 3 patients. Segmental contractility similarly deteriorated in the latter 3 patients but also in 2 patients whose perfusion scan had improved with exercise. Three patients, normal at rest, developed segmental hypokinesia during exercise. When present, the location of observed changes in contractility on stress echocardiography corresponded to that of perfusion defect. In conclusion, abnormal myocardial perfusion is present long term after complicated Kawasaki disease, the worst anomalies accompanying persistent giant aneurysms. Unfavorable perfusion response was coupled with abnormal contractility; however, enhanced perfusion with exercise correlated poorly with segmental contractility response.

Effect of intermittent positive pressure ventilation on diastolic ventricular filling patterns in premature infants

Eleven preterm newborn infants had a Doppler echocardiographic examination of their ventricular filling patterns during intermittent positive pressure ventilation. Peak velocity during early ventricular filling (VE) and during atrial systole (VA) and diastolic velocity-time integral of early (IE) and late (IA) ventricular filling caused by atrial contraction were measured. The ratios of VE/VA and IE/IA were also calculated. Diastolic peak velocities, as well as the diastolic velocity-time integral of early and late ventricular filling measured through the mitral valve were significantly higher during inspiration. The peak of the wave representing the velocity during atrial systole (A) was always higher than the peak of the wave representing the velocity of early ventricular filling (E). As a result, the ratio of these two variables (E/A) was always less than 1, showing no significant variation from inspiration to expiration. The flow patterns into the right ventricle were the opposite of those observed through the mitral valve. During inspiration, a significant decrease (p less than 0.001) in peak and time integral velocities of both the early ventricular filling and atrial systole waves was observed. Heart rate did not vary with respiration. It is concluded that during positive pressure ventilation, inspiration decreases right ventricular filling and enhances left ventricular filling. Opposite changes are recorded during expiration. Early and late phases of diastolic filling are equally affected. These changes are different from those observed during spontaneous breathing and should be taken into account in the assessment of diastolic ventricular function in preterm infants requiring assisted ventilation.

Implanting telehealth network for paediatric cardiology: learning from the Quebec experience

The implementation committee of the Quebec Child Telehealth Network was formed in 1997, with a mandate to build a network dedicated to the diagnosis of congenital cardiac disease via telemedicine. We devised criterions for selection to determine which peripheral centres would be linked by telemedicine to the university-based services for paediatric cardiology provided in the Canadian Province of Quebec. The criterions included: distance from a university centre, number of births per year, and presence of an already-established outreach clinic for paediatric cardiology. The Quebec Network became operational in 2000, and was composed of 32 peripheral centres and 4 university centres. A total of 363 transmissions of echocardiograms occurred over a 3-year period from January 2000 to December 2002. Peripheral centres located at a distance greater than 100 kilometres from a university centre were 8.5 times more likely to use the network. Criterions other than distance did not influence whether or not a peripheral centre used the network. Cardiac abnormalities were identified in almost two-thirds of the transmissions. The use of the Quebec Network resulted in the avoidance of transfers or clinic visits to university hospitals in seven-tenths of cases. We conclude that distance greater than 100 kilometres from a centre offering subspecialty services in paediatric cardiology is the most important criterion for choosing the peripheral centres that are most likely to use a telehealth network. In its first three years of operation, the telehealth network had a major impact on the delivery of paediatric cardiac care, improving access to subspecialty services across the province.

Inferior Vena Cava Stenosis in Scimitar Syndrome: A Case Report

The scimitar syndrome, first described by Chassinat in 1836, consists aessentially of an anomalous pulmonary vein draining whole or part of the right lung into the inferior vena cava. Associated anomalies are frequent, such as hypoplasia of the right lung, dextrocardia, malformations of the right pulmonary artery and bronchial tree, and abnormal arterial supply of the right lung (the so-called sequestration). This article describes a scimitar syndrome associated with stenosis of the inferior vena cava, whose initial diagnosis was made by two-dimensional echocardiographic Doppler color flow mapping. To our knowledge this is the first description of such an unusual association.