Since February 1990, we have attempted nonsurgical occlusion of persistent patency of the arterial duct using the Rashkind double-disk occluding device, of either 12 or 17 mm diameter. Results are presented from 31 patients (23 female and eight male, ages 15 months to 16 years). M-Mode, cross-sectional, Doppler and color Doppler echocardiographic studies were made prior to closure, in the following 24 hours, and six months later. Left ventricular diastolic dimension and shortening fraction, systolic intervals, and left atrium/aortic ratio were evaluated by M-Mode echo. We examined carefully the location of the device relative to the left pulmonary artery and descending aorta, also checking for disturbed flows and residual shunts. These studies showed a clear tendency for the left ventricular diameter to decrease, and revealed a significant normalization of the left atrium/aortic ratio. Successful closure of the duct was achieved in 27 cases. Follow-up studies six months later showed residual shunting in four cases. In one patient, a second device was implanted with an excellent result. At the immediate follow-up, turbulences were noted in the area of the device (nine cases) and in the left pulmonary artery (seven cases). Distortion of the anatomic orientation of the left pulmonary artery was observed in three cases in which we discovered 20 mm Hg systolic gradients. In our opinion, echocardiography is the best technique with which to follow-up these patients. The high sensitivity of color Doppler echocardiography revealed minimal distortion of the left pulmonary artery, probably generated by regional anatomic adjustment to the insertion of the device.

M-mode, cross-sectional and color flow Doppler echocardiography were performed in 28 patients with acute rheumatic fever. The patients were grouped according to the presence or absence of carditis and congestive heart failure. Abnormal echocardiographic findings were found in 25 patients (89%), including five with no carditis. M mode echocardiography showed significant cardiac enlargement in all patients with carditis, and in two patients with no carditis. The myocardial contractility, as based on ejection fraction and fractional shortening, was normal in all patients except one. Prolapse of the leaflets of the mitral valve (57%) and increased echogenicity of the leaflets of the mitral valve (36%) were the most common findings seen on cross-sectional echocardiography. Pericardial effusion was seen in six patients (21%), all with heart failure. Color flow and Doppler echocardiography showed that mitral regurgitation, which was seen in 24 patients (86%), was the most common finding. Aortic regurgitation was found in 17 patients (60%). The presence of congestive heart failure in patients with carditis was related to the severity of the valvar regurgitation and the number of valves involved. Echocardiographic evidence of rheumatic involvement of the heart may be observed even in the absence of clinical signs of carditis.

Two infants, aged eight days and four months, with tetralogy of Fallot and absence of the leaflets of the pulmonary valve, presented with acute respiratory distress and congestive heart failure. Primary repair was performed using a cryopreserved pulmonary arterial homograft. Both infants survived and are doing well three and two years later. A review of the surgical procedures attempted in this symptomatic group of patients is presented together with a discussion of the pathophysiology of this defect.

To study the effect of maturational geometric changes on flow characteristics in the pulmonary artery trunk, anatomically accurate, acrylic flow-through models were constructed from four flexible silicone rubber casts obtained in situ in lambs weighing 2.4, 7.8, 9.5, and 11.5 kg. A silicone rubber cast of the right heart was fabricated by injecting the superior caval vein in situ with liquid silicone rubber (Dow Corning's HS-II RTV, Midland, MI). Each cast was used as a template for a transparent acrylic mold of the pulmonary artery trunk and primary generation branches. The acrylic block was then fitted with a curved rigid Plexiglass inflow tube (to simulate the curvature of the right ventricle) just proximal to the pulmonary valve sinuses and mounted in a closed loop system driven by a variable speed pulsatile pump (to simulate physiological flow rates between 0.5 and 4.0 lmin−1) A blood analog solution of polystyrene beads (Rohm & Haas Amberlite, Philadelphia, PA) suspended in a 45% by weight glycerine solution was illuminated by a laser source (15 mwatts, Siemens, Germany) to trace the flow patterns. Two flow field planes of the main pulmonary artery trunk—one parallel, and one perpendicular, to the origins of the right and left arterial branches—were visualized and video recorded (Canon H660 8mm, Japan) for subsequent analysis. A prominent vortex, originating in the center of the main pulmonary artery and directed inferiorly toward the inner wall, was noted in the flow field plane perpendicular to the bifurcation in the 9.5 and 11.5 models. These characteristics were less developed in the 7.8 kg model and not present in the 2.4 kg model, possibly because the angle of curvature was less acute than in the larger models. In the flow field plane parallel to the bifurcation, the patterns were more complex, principally influenced by turbulence in the main pulmonary artery (which increased at higher flow rates) and the geometric changes in the branch pulmonary arteries.

We studied 56 children echocardiographically, ages four to 15 years (mean nine years) with acute rheumatic fever to determine the extent of cardiac involvement. All had a clinical diagnosis of carditis. Mitral regurgitation was always present and was associated with aortic regurgitation in 53.6% and tricuspid regurgitation in 32.1%. Mitral valvar prolapse was observed in 18 patients 5(32.1%) and could not be differentiated from myxomatous prolapse in 10 (17.8%). Cordal rupture was detected in seven patients (12.5%), three of whom required surgical treatment. Other findings concerning the mitral valve were vegetations in two patients (3.6%), commissural fusion without stenosis in 36(64.3%), and mitral stenosis in four (7.1%). Heart failure was usually secondary to valvitis rather than myocarditis, and led to surgical treatment in seven patients. The myocardial function was depressed in only two patients. In both, the ejection function returned to normal after medical treatment. Echocardiography provides important information on the involvement of the heart in acute rheumatic fever, helping to determine prognosis and the results of treatment.

Although pulmonary vascular disease occurs in association with pulmonary venous obstruction, a model of pulmonary vascular lesions in this setting in small laboratory animals has yet to be described. The objective of this study was to determine if unilateral banding of pulmonary veins in the rat would produce pulmonary vascular disease that mimicked key aspects of the human disorder. Rats were anesthetized and, after mechanical ventilation and thoracotomy, one of the four pulmonary veins was banded to reduce its external diameter by approximately 65–75% to 0.8 mm. Additional animals, sham-operated controls, were treated identically except for venous banding. Mortality did not differ between groups and was less than 20%. Eight weeks after surgical preparation, moderate pulmonary hypertension was demonstrated with a mean pressure in the pulmonary artery of 24.9 mm Hg (range 19.25 – 30.0) in the banded group versus 18.7 mm Hg (range 16.6 – 19.3) for sham-operated animals. Pulmonary cineangiography in rats with banded pulmonary veins demonstrated marked pulmonary congestion and a prolonged residence time of contrast medium in the capillary circulation of the lung region subjected to banding. Angiographically, non-banded lungs were similar to shams. Histopathology of the vein-banded region revealed venous congestion, arterialization of veins, perivenular edema, and sparse to moderate inflammation. Prominent bronchial vessels, pulmonary arterial medial and occasional intimal thickening, and periarterial inflammation were also observed in banded regions. Similar inflammation around pulmonary arterial and pulmonary venous vessels was noted in contralateral lung lobes but not in sham-operated control rats. Morphometric evaluation of all muscular pulmonary arteries from 50–200μ external diameter accompanying airways to the level of terminal and respiratory bronchioles indicated that the medial area in lung regions subjected to venous banding was over three times greater than in shams. Pulmonary arteries from the contralateral, unbanded lungs of treated animals also exhibited a two-fold increase in medial area. These findings indicate that a modest degree of pulmonary venous banding in rats produces congestion and causes alterations in lung vessels which are reminiscent of those observed in humans with pulmonary venous outflow obstruction. Such a model in a cost-effective laboratory animal should be useful for delineating the specific mechanisms underlying these alterations.

Sinus venosus defects are relatively uncommon forms of interatrial communication in which one of the caval veins has a biatrial connection, and partial anomalous pulmonary venous connections are the rule. The variety related to the inferior caval vein is much the rarer of the two forms, and here the defect is posterior and inferiorly placed. To determine whether an inferior sinus venosus defect could be identified preoperatively, we reviewed retrospectively the available echocardiograms and cineangiograms of the five patients with an inferior sinus venosus defect who underwent surgical repair between January 1983 and December 1991. A cross-sectional echocardiogram had been performed preoperatively in four of these patients, but the correct diagnosis had been made in only one case. Retrospective study, however, showed that the extent of the true atrial septum and the nature of the junction of the inferior caval vein with the atriums could be evaluated from the subcostal position in three of these four patients. Each of the three had an interatrial communication located posteriorly and inferiorly adjacent to the atrial connection of the inferior caval vein, along with abnormally connected right pulmonary veins. The oval fossa was intact and the coronary sinus was normal in all. Cardiac catheterization had been performed in three of the five patients. Anomalous return of right pulmonary veins was noted in each, and the posterior and inferior location of the interatrial communication was evident in two. An interatrial communication adjacent to the atrial connection of the inferior caval vein, along with anomalous connection of the right-sided pulmonary veins, are the diagnostic features of the inferior variety of sinus venosus defects. These features can be demonstrated by cross-sectional echocardiography from the subcostal position.

To assess whether paradoxical (systolic anterior) motion of the interventricular septum is a true abnormality of septal contraction caused by right ventricular volume overload, we examined the regional pattern of left ventricular contraction in 20 patients with an atrial septal defect within the oval fossa using a fixed and floating reference system of analysis of wall motion. The patients, with a median age of 6.8 (3.5–13.4) years, had a Qp/Qs ratio of 3.5:1 (1.2:1–8:1). They were studied by cross-sectional echocardiography four days (3–5) before and 14.5 (3–67) days after surgical closure of the atrial septal defect. The postoperative Qp/Qs ratio was 1.1:1 (0.9:1–2:1). Regional wall motion of the left ventricle was analyzed in the parasternal short axis view at the level of the mitral valve and papillary muscles as well as in the apical four-chamber view. The endocardium was digitized manually in end-systolic and end-diastolic frames. The center of mass of this figure was calculated and connected to an outside reference point in the right ventricle. With the floating system, both centers of mass and the reference lines were superimposed, thus correcting for movement of the heart inside the thorax. With the fixed system,both end-diastolic and end-systolic frames were measured separately without correcting for movement of the heart. The left ventricle was divided in eight segments in a clockwise fashion and regional change in area was measured and compared to 40 normal age matched controls. With the floating system, left ventricular regional wall motion was normal in all patients before and after closure of the atrial septal defect and, thus, was not influenced by the change in right ventricular volume load. With the fixed system, both before and after surgical closure of the atrial septal defect, left ventricular regional wall motion was reduced in the two segments representing the basilar and middle portion of the interventricular septum. The floating system of analysis of left ventricular regional wall motion has the ability to correct for movement of the heart, which makes the supposed “abnormal” systolic anterior motion in right ventricular volume overload, a condition prevalent in patients with atrial septal defect, disappear. Thus, we conclude that the so-called paradoxical septal motion in atrial defect is an artifact. This may be caused by an increased motion of the heart but is unrelated to the volume load of the right ventricle.

To assess the prevalence and role of the arterial duct in hearts with incomplete development of the aorticopulmonary septum, 110 autopsy specimens, comprising 100 examples of common arterial trunk and 10 cases with aorticopulmonary window, were studied. In addition to intracardiac malformations, these specimens were analyzed to determine the side of the aortic arch, the presence and location of any interruption of the arch, the presence of any anomaly of origin and course of the subclavian arteries, and the status of the arterial duct. The arterial duct was present in 33 cases, absent in 63 cases and undetermined in four cases with common arterial trunk. The duct provided an essential pathway for flow in the 20 cases with interrupted aortic arch, and in two cases with interruption of the proximal portion of the left pulmonary artery. The presence of the duct in 11 cases, in functional terms, was not essential. In the 10 hearts with aorticopulmonary window, the duct was present in eight. It was an obligatory part of the circulatory pathways in three cases where the aortic arch was interrupted. The prevalence of non-obligatory ducts was 71% in hearts with aorticopulmonary window compared to 15% in hearts with common arterial trunk. The prevalence of the duct in cases with aorticopulmonary window suggests this lesion is a later developmental defect. The functional role of an arterial duct in these hearts should be properly assessed in the clinical situation.

Although noninvasive estimation of the ratio of pulmonary to systemic flow by measuring the cross-sectional areas of the pulmonary and aortic valves and the respective time integrals of the velocity of blood is widely used to determine the amount of shunting in patients with left-to-right shunts, few data exist concerning interobserver variability. We assessed such variability of shunt calculations derived from Doppler echocardiography in 10 children aged six (3.5–11) years with an isolated atrial septal defect within the oval fossa. The ratio of flows was calculated by measuring stroke volumes over the pulmonary trunk and the aorta immediately before and at an average of seven days (5–11) following surgical closure of the atrial septal defect. Two independent observers measured the cross-sectional areas of the aortic and pulmonary orifices and the velocity time integrals and calculated the size of the shunt from these data. All measurements were performed five times, and the mean of these five measurements was calculated and compared for analysis. Before surgery, observer I had measured a ratio of pulmonary to systemic flow of 3.8 (2.1–6.2) and observer II of 3.5 (1.9–5). The mean interobserver difference in terms of the size of the shunt was 1.1 (or 30%). After surgery, observer I measured a ratio of 1.3 (0.8–1.7) and observer II of 1.1 (0.7–1.6). The cross-sectional area of the pulmonary valve was measured as 3.6 (2.6–4.9) cm2 and 3.4 (2.3–5.8) cm2 respectively, with a mean interobserver difference of 0.8 cm2 or 23%. For the velocity time integrals across the pulmonary trunk, the mean interobserver difference was 13% (4–38) before and 16% (0–55) after surgery. The respective variability for the aortic velocity time integrals was 11 % (4–46) before and 9% (0.5–23) after surgery. The variability of measurements of maximal flow velocity across the pulmonary trunk was 15% (4–38) before and 18% (1–77) after surgery. The respective variability for the aortic flow velocity was 11 % (2–28) before and 9% (4–23) after surgery. A paired t-test showed no significant differences for all parameters assessed. The difficulty of reproducing measurements of the pulmonary valve is an important factor affecting interobserver variability. The magnitude of interobserver difference was significantly related to the cross-sectional area of the pulmonary trunk (r=0.84; p<0.02). The interobserver variability may be considerable, and is large enough to influence clinical decisions. Thus, we conclude that a decision regarding need for surgery cannot be based solely on calculation of the shunt derived only from Doppler measurements in patients with isolated atrial septal defects within the oval fossa.

The prognosis for the fetus or neonate with asplenia syndrome is unknown as population-based data are unavailable. Factors influencing survival in this syndrome were, therefore, assessed for the province of British Columbia by retrospective review of all cases diagnosed between 1970 and 1990. Particular attention was paid to the prognostic influence of palliative surgery, sepsis, extracardiac malformations, gastrointestinal disease, arrhythmias and sudden death. We identified 43 cases of asplenia syndrome, of which 40 were live-born (incidence 1/22,000 live‐births). Only one spontaneous death was noted during fetal life amongst approximately 5,000 fetal autopsies. Five cases had been diagnosed by fetal echocardiography, two of these pregnancies being terminated. Of the live-born infants, 28 (70%) underwent active management of their cardiac anomalies and of these, 14 are alive. Since 1980, 26 systemic-to‐pulmonary shunts have been constructed in 17 children with two operative deaths. Three children have had successful Fontan or bidirectional Glenn procedures. Systemic sepsis occurred in three children with no deaths. Three neonates underwent surgery for obstruction of the upper gastrointestinal tract without complication. Late sudden death occurred in four children with systemic-to-pulmonary shunts, none of whom had documented arrhythmias. Major extracardiac malformations were present in nine cases (21%), these contributing to death in two. Overall survival for all live-born infants is 35%. Sepsis and palliative surgery are no longer the major causes of death in asplenia syndrome, the current challenges being prevention of sudden death and the complexity of surgical repair of the cardiac malformations.

Five previously reported cases have established the combination of a small right ventricle (sometimes with Uhl's anomaly), imperforate tricuspid valve with fibrotic tensor apparatus, congenital absence of the pulmonary valve, and an intact interventricular septum with muscular subaortic stenosis as a rare variant of tricuspid atresia. In this study of three new autopsy cases, we additionally identified Ebstein's malformation of the imperforate tricuspid valve, partial Uhl's anomaly, regional dysplasia of right ventricular myocardium and thinning of the interventricular septum by intramyocardial sinusoids from the right ventricle. All three new cases had epicardial anomalies of the right coronary artery—a fistula to right ventricle, ostial stenosis and proximal arterial hypoplasia. Sinusoidal connections from the right ventricle to the right coronary artery and to the sclerotic left anterior descending artery were identified in serial sections of the right ventricle and septum. Myofiber disarray, with thick walled intramyocardial arteries and sinusoids from left ventricle, involved the bulging subaortic interventricular septum. These studies are consistent with the hypothesis that defective development of the the right ventricle, along with its blood supply and associated atrioventricular and arterial valves, may underlie this unusual form of congenital heart disease.

After an initial attempt to close arterial ducts by the transcatheter insertion of an umbrella device had left significant residual patency, further attempts at closure were made in 14 patients by the insertion of an additional umbrella device. The ages of the patients ranged from four to 11 years. Overall, 17 attempts were made to insert additional devices at intervals of between six to 26 months after the insertion of the first umbrella. Successful insertion of a device was achieved in two patients only at a third attempt. One patient required the insertion of a third umbrella to achieve complete occlusion of the patent duct. Complete closure of the residual patency was achieved in 13 of the 14 patients. The remaining patient has been scheduled for insertion of a third umbrella.

Eight patients, four males and four females, age five to 13 years old (average: 11 years) have undergone surgery in the acute phase of rheumaticfever. The patients presented a history of rheumatic activity characterized by the presence of migratory arthritis and carditis. All patients had severe acute mitral insufficiency, while one of them had associated aortic insufficiency. Laboratory examinations revealed the presence of an acute inflammatory condition. All patients had acute heart failure and were treated initially with high doses of diuretics, peripheral vasopressor and vasodilator amines, together with cardiotonic drugs, without improvement. Surgical treatment was indicated after a period of observation between 24 hours and five days. In five patients, the Doppler echocardiogram revealed rupture and elongation of tendinous cords. Two of them had acute dilatation of the mitral ring, and one had isolated acute dilatation of the mitral ring. Five patients underwent valvar replacement and, in three, valvar repair was carried out. Two patients, who were in cardiogenic shock at the time of their referral, died in the operating room following replacement of the mitral valve. All patients who underwent repair of the mitral valve were in good condition at the last follow-up, six to 27 months after surgery.

The incidence and spectrum of extracardiac malformations in congenital asplenia syndrome were determined by review of43 cases (40 live-births) identified in the province of British Columbia over a 21 year period. Major extracardiac anomalies (excluding those of abnormal arrangement of the organs) were identified in nine cases (21%), and minor anomalies were present in an additional twelve infants (28%). Extracardiac anomalies were associated with one spontaneous stillbirth, one termination of pregnancy, and two early neonatal deaths. In an additional four newborns, they contributed to a decision not to palliate the complex cardiac anomalies. Gastrointestinal malformations led to neonatal intestinal obstruction in four infants. Of the 14 surviving children, one is severely handicapped due to a congenital anomaly of the central nervous system. The clinical significance of extracardiac malformations and their developmental implications are discussed.

Although declining in the so-called “first world,” surgery for rheumatic valvar lesions in patients less than 16 years of age is still a challenging problem in lesser developed countries. From 1970 to 1990, we operated upon and followed-up 136 children (less than 16 years) with different valvar lesions, performing various surgical procedures. The mitral valve was most frequently affected (52.9%) followed by multiple valvar disease (39.7%) and aortic (7.3%) involvement. The operations performed were valvoplasties (67), valvar replacement (49), and combined procedures (20). Hospital mortality for the overall group was 10.2%. There were 71 reinterventions in the follow-up of 20 years. Actuarial survival was 60.3% including hospital mortality. The event-free actuarial survival showed that 91% had at least one major event which required reoperation or hospital treatment, or else invasive cardiac procedures. We conclude that rheumatic valvar disease is still a challenging problem in our country, and that the severity of the illness is directly related to the younger age patients. In spite of reasonable long-term survival, very few patients had an uneventful follow-up after surgery.

Right ventricular dominance was observed in 22 (6.6%) out of 332 patients with atrioventricular septal defects. Their mean age was 2.24 ± 2.73 months. Chromosomal anomalies were seen in only three patients (Down's syndrome in two and trisomy nine in one). Seventeen patients underwent surgical treatment. A pulmonary artery banding was performed in eight of them with one long-term survivor who underwent a successful staged orthoterminal repair. A Norwood-type of palliation was attempted in four without success. Biventricular repair was performed in four additional patients with two mid-term survivors, in one of whom the patch used for closure of the atrial septal defect was fenestrated. One patient underwent successful heart transplantation at seven months of age. Pathophysiological problems and surgical options are discussed.

A 21-day-old girl presented with congestive heart failure of acute onset and Doppler evidence of mitral regurgitation, which subsequently proved fatal. Necropsy revealed an anomalous arcade lesion of the mitral valve. The tendinous cords of the tricuspid valve were also abnormal, a finding, to the best of our knowledge, not reported before.

The incidence of spontaneous closure of uncomplicated defects of the oval fossa was determined in cohort of 498 children. Surgical repair was accomplished in 428 at a median age of 4.5 years. Of the 70 who did not undergo surgery, 20 showed spontaneous closure or a decrease in size of the defect. The defect was unchanged in the other 50. The age at diagnosis, pulmonary-to-systemic flow ratio and size of the defect were not statistically significantly different in the changed and unchanged groups, and there was no difference in prevalence of symptoms, the triad of systolic and diastolic murmurs and abnormal splitting of the second sound, or of right ventricular enlargement by echocardiography. The rate of spontaneous diminution in size or actual closure of a defect in this series was 4%, and no clinical predictor of change in the size of a defect was identified. Thus, delay in repair of a large flow atrial septal defect in the hope of spontaneous closure is not justified, whether or not symptoms are present.