Outcome after preterm delivery of infants antenatally diagnosed with congenital heart disease.

OBJECTIVE: To determine outcome of delivery before 36 weeks gestation in babies diagnosed antenatally with serious congenital heart disease (CHD). STUDY DESIGN: A retrospective database review at 2 tertiary care fetal cardiology centers. Details of neonatal course and outcome were obtained for those antenatally diagnosed with serious CHD who were live born before 36 weeks gestation. RESULTS: Between January 1998 and December 2002, 9918 women were referred for fetal echocardiography. Serious CHD was diagnosed in 1191 fetuses (12%), of which 46 (4%) delivered prematurely. Median gestation was 33 (range 24-35) weeks, and median birth weight 1.56 (0.50-3.59) kg. Extracardiac/karyotypic anomalies occurred in 23 (50%). Twenty-six babies (57%) underwent neonatal surgery: 16 a cardiac procedure, 5 a general surgical procedure, and 5 both. Eight died during or after operation (31%). Two babies underwent interventional heart catheterization; both died. The overall mortality rate was 72%. Extracardiac/karyotypic anomalies increased the relative risk of death by a factor of 1.36. Mean hospital stay for those surviving to initial discharge was 46 (2-137) days. CONCLUSIONS: There is a very high morbidity and mortality rate in this group, particularly for those with extracardiac/karyotypic anomalies. This should be reflected in decisions over elective preterm delivery and when counseling parents.

Echocardiographic assessment of conjoined twins.

OBJECTIVE: To determine the accuracy of prenatal and postnatal echocardiography in delineating the degree of cardiac fusion, intracardiac anatomy (ICA), and ventricular function of 23 sets of conjoined twins with thoracic level fusion presenting to a single centre over a 20 year period. METHODS: 13 thoracopagus, 5 thoraco-omphalopagus, and 5 parapagus pairs presenting to the authors' institution between 1985 and 2004 inclusive were assessed. Echocardiographic data were analysed together with operative intervention and outcome. Twins were classified according to the degree of cardiac fusion: separate hearts and pericardium (group A, n = 5), separate hearts and common pericardium (group B, n = 7), fused atria and separate ventricles (group C, n = 2), and fused atria and ventricles (group D, n = 9). RESULTS: The degree of cardiac fusion was correctly diagnosed in all but one set. ICA was correctly diagnosed in all cases, although the antenatal diagnosis was revised postnatally in three cases. Abnormal ICA was found in one twin only in two group A pairs, one group B pair, and both group C pairs. All group D twins had abnormal anatomy. Ventricular function was good in all twins scanned prenatally, and postnatally function correlated well with clinical condition. Thirteen sets of twins in groups A-C were surgically separated; 16 of 26 survived. None from groups C or D survived. CONCLUSIONS: Prenatal and postnatal echocardiography accurately delineates cardiac fusion, ICA, and ventricular function in the majority of twins with thoracic level fusion. It is integral in assessing feasibility of separation. The outcome in twins with fused hearts remains dismal.

Dynamic three-dimensional color Doppler ultrasound of human fetal intracardiac flow.

OBJECTIVES: To develop dynamic three-dimensional ultrasound techniques for prenatal imaging of the intracardiovascular flow as well as the cardiovascular structure to address difficulties in assessing the spatially complex hemodynamics and morphology of the fetal heart. METHODS: Gray-scale and color (velocity) Doppler echocardiography were performed on 12 fetuses to provide serial anatomical and rheological tomograms which were spatially registered in three dimensions. Using a second ultrasound machine simultaneously, spectral Doppler ultrasound was performed to record umbilical arterial waveforms, thus providing the temporal (fourth) dimension in terms of the cardiac cycle and facilitating removal of motion artifacts. RESULTS: Acquisitions were successful in eight of 15 attempts. Imaging of the flow of blood in four dimensions was achieved in six of the eight datasets. In one case with complex cardiac malformations, three-dimensional reconstructions at systole and diastole offered dynamic diagnostic views not appreciated on the cross-sectional images. CONCLUSIONS: Our novel technique has made possible the prenatal visualization of the spatial distribution and true direction of intracardiac flow of blood in four dimensions in the absence of motion artifacts. The technique suggests that diagnosis of cardiac malformations can be made on the basis of morphological and hemodynamic changes throughout the entire cardiac cycle, offering unique and significant information complementary to conventional techniques. Further work to integrate the several non-purpose-built machines into a single system will improve the rate of acquisition of data, and may provide a new means of imaging and modeling structure and hemodynamics, not only for the fetal heart but for many other moving body parts.

Influence of the introduction of Amplatzer device on the interventional closure of defects within the oval fossa in children.

Since June 1998, we have used an Amplatzer device whenever considered appropriate in patients with isolated defects within the oval fossa. The aim of this study was to define the total cohort of patients with isolated defects in the oval fossa seen at this hospital, so as to assess the impact of this policy on contemporary management. In the two-year period commencing 1st June 1998, 116 patients older than 6 months were seen with an isolated septal defect within the oval fossa. Mean age at closure or last review was 5.8 years, with a range from 0.5 to 20 years. In total, 42 (36%) patients were assigned to surgical closure, 25 (22%) to closure using an Amplatzer device, and 49 (42%) remained under clinical follow up. Direct referral for surgical closure occurred in 24 (21%) patients, in whom transcatheter closure was considered not appropriate after transthoracic echocardiography. Transoesophageal echocardiography was performed in 45 (39%) patients to assess suitability for closure using the Amplatzer device. Of these, 20 (44% of the group undergoing transoesophageal echocardiography) were considered unsuitable for closure in this fashion. Of these, 18 were referred for surgery and 2 with small defects were considered not to require closure. Patients undergoing closure with the device were older than the group referred for surgical closure, having a median age of 7.8 versus 3.6 years, and stayed for a shorter period in hospital. Those closed using the device stayed for 2 days, as opposed to a median of 5 days, with a range from 4 to 10 days for those undergoing surgical closure. Closure was complete as assessed by echocardiography after follow up of 1-3 months in both groups. There were no recognised complications related to insertion of the device, whereas transient postoperative morbidity occurred in 38% of those closed surgically. Insertion of an Amplatzer device was considered to be appropriate in 37% of patients older than 6 months requiring closure of an atrial septal defect in the oval fossa.

Urgent homograft aortic root replacement for aortic root abscess in infants and children.

OBJECTIVE: To assess the results of early homograft aortic root replacement in infants and children with an aortic root abscess. DESIGN: Descriptive study of all patients with an aortic root abscess during 1987-97, identified by retrospective review of the echocardiographic and surgical registries. SETTING: A tertiary referral centre. PATIENTS: Five patients (age 0.6 to 13 years; two female) were identified with an aortic root abscess. Four had no known pre-existing congenital heart abnormality. Three had a misleading presentation and were referred to our hospital with non-cardiac diagnoses (fulminant hepatic failure; adult respiratory distress syndrome; cerebrovascular accident). The other two presented with septicaemia and a murmur, respectively. Blood cultures identified Staphylococcus aureus (n = 3) and Streptococcus pneumoniae (n = 2). Aortic root abscess was diagnosed by transthoracic echocardiography. INTERVENTIONS: Homograft aortic root replacement with coronary reimplantation was performed urgently (median one day after diagnosis). RESULTS: Four patients survived. The youngest died following multiorgan failure, multiple aortic fistulae, three valve involvement, and extensive tissue destruction preventing mitral valve replacement (S pneumoniae). Two of the four survivors have required further surgery: mitral valve replacement (0.3 years later), and pulmonary autograft replacement of the homograft (8.3 years later). All survivors remain in sinus rhythm and New York Heart Association functional class I. CONCLUSIONS: Infective endocarditis should be considered in any child with severe septicaemia or embolic phenomena. Echocardiographic diagnosis of an aortic root abscess indicates uncontrolled infection and impending haemodynamic collapse. Homograft aortic root replacement can be performed successfully in critically ill children with active infection.

Primary arterial switch operation for transposition of the great arteries with intact ventricular septum in infants older than 21 days.

OBJECTIVES: The aim of this study was to assess the surgical outcome of the primary arterial switch operation (ASO) in infants 3 weeks to 2 months old. BACKGROUND: The surgical management of transposition of the great arteries and intact ventricular septum (TGA/IVS) beyond 2 to 3 weeks of age is controversial. Concern that regression of the left ventricular (LV) myocardial mass will render the left ventricle incapable of coping with the acutely increased work of systemic perfusion has been considered a contraindication to a primary ASO. METHODS: We used retrospective analysis of 37 patients 3 weeks to 2 months old and 156 patients <3 weeks old who underwent primary ASO with TGA/IVS to determine the surgical outcomes. RESULTS: Between January 1990 and December 1996, primary ASO was performed in 37 patients 21 to 61 days old (late ASO group) and 156 patients <21 days old (early ASO group) with TGA/IVS. One (2.7%, 95% confidence interval [CI] 0.07% to 14.2%) of 37 patients and 13 (8.3%, 95% CI 4.5% to 13.8%) of 156 patients died. One late death occurred in each group. Mechanical LV support was required in 1 (2.7%, 95% CI 0.07% to 14.2%) of 37 late ASO and 6 (3.8%, 95% CI 1.4% to 8.2%) of 156 early ASO group patients postoperatively. Neither death nor the need for mechanical LV support in the late ASO group patients could be attributed to LV failure. In the late ASO group, age, LV geometry, LV mass index, LV posterior wall thickness index, LV volume index, LV mass/volume ratio, patent arterial duct or pattern of coronary anatomy did not predict death, duration of postoperative ventilation or inotropic support or time in intensive care. Moreover, there was no difference in duration of ventilation, duration of inotropic support or the time spent in intensive care in comparison to a random sample of 37 neonates from the early ASO group. CONCLUSIONS: Primary ASO may be appropriate treatment for infants with TGA/IVS < or = 2 months old, regardless of preoperative echocardiographic variables. The upper age limit for which primary ASO is indicated in TGA/IVS is not yet defined.

Familial neonatal atrial tachycardia.

A father and his two sons each presented with atrial tachycardia in the newborn period. The father went on to develop dilated cardiomyopathy. The first son (who also had transposition of the great arteries) died from the arrhythmia after surgery. The second son is currently successfully managed pharmacologically.

Hypoplastic left heart syndrome in the second trimester.

Hypoplastic left heart syndrome is a relatively common congenital anomaly with a high mortality even after palliative postnatal surgery. The case presented had a normal cardiac cavity and great artery dimensions at 19 weeks of gestation but bright left ventricular myocardial echoes, impaired left ventricular shortening, and no detectable forward flow in the left ventricular outflow tract. Autopsy showed left ventricular subendocardial calcification. This demonstrates a likely early stage in the evolution of hypoplastic left heart syndrome, which has a variable time course. The abnormal left ventricular myocardial performance associated with low left ventricular output results in a failure of growth of the left heart rather than there being a primary failure of embryogenesis.

Late outcome of survivors of intervention for neonatal aortic valve stenosis.

BACKGROUND: This study examined the late outcome after intervention for neonatal aortic valve stenosis. METHODS: Seventy-three neonates (59 boys and 14 girls) underwent intervention for critical aortic valve stenosis during the first 30 days of life at two institutions, The Hospital for Sick Children, London, and Duke University Medical Center, Durham, North Carolina. Procedures performed include closed valvotomy (n = 12), open valvotomy with inflow occlusion (n = 14), open valvotomy with cardiopulmonary bypass (n = 33), balloon valvotomy (n = 12), and other procedures (n = 2). The mean age at the first intervention was 8 +/- 1 days. RESULTS: The hospital mortality was 52.1%. The mean duration of follow-up for the hospital survivors (n = 35) was 8.3 +/- 1.1 years. The actuarial survival for the hospital survivors was 93.3% +/- 4.7% at 10 years and 83.9% +/- 9.8% at 15 years, whereas event-free survival (reintervention, endocarditis, or early death) was 61.8% +/- 9.3% at 5 years, 34.2% +/- 10.8% at 10 years, and 27.4% +/- 10.6% at 15 years. Three patients have died and 11 patients have required aortic valve replacement during the follow-up period. The age at the initial intervention, the type of initial intervention, and the year of initial intervention were not predictive of early death or need for reintervention. At last follow-up, 26 of the long-term survivors (n = 32) were in functional class I and 6 were in functional class II. CONCLUSIONS: Aortic stenosis in the neonatal period is a difficult problem with a high initial mortality. Late survival and functional class are excellent for patients surviving the initial hospitalization, but most require further intervention within 10 years.

Heart transplantation in an infant with rhabdomyoma.

Rhabdomyoma is the most common primary cardiac tumor in infants and children and is often associated with tuberous sclerosis. Surgical resection may be indicated and, if so, is usually curative. We describe a rhabdomyoma in an infant who presented with severe myocardial ischemia necessitating orthotopic heart transplantation.

Repair of anomalous pulmonary venous connection to the superior vena cava.

Complex forms of anomalous pulmonary venous connection to the superior vena cava (SVC) can be difficult to correct surgically. Since 1987, 11 patients have undergone repair of anomalous pulmonary venous connection to the SVC by diversion of the pulmonary venous drainage to the left atrium using a baffle with division of the SVC and reimplantation on the right atrial appendage to restore normal systemic venous drainage. Total anomalous pulmonary venous connection was present in 3 patients and partial anomalous pulmonary venous connection, in 8. All patients are alive and asymptomatic at a mean follow-up of 2.3 +/- 1.4 years. Postoperative echo-cardiograms (8 patients) revealed pulmonary venous obstruction requiring reoperation in 1 patient. No patient has clinical evidence of SVC obstruction, and all are in sinus rhythm. This is a safe and effective technique for repair of complex forms of anomalous pulmonary venous connection to the SVC, and the incidence of postoperative venous obstruction and rhythm disturbances is low.

Supravalvar mitral stenosis: risk factors for recurrence or death after resection.

OBJECTIVE: To assess the medium term outcome in infants and children after surgical resection of supravalvar mitral stenosis with special reference to risk factors for mortality or recurrence of supravalvar mitral stenosis. No detailed follow up has been previously reported in this uncommon condition. DESIGN: Prospective cross sectional clinical and echocardiographic follow up. SETTING: Paediatric cardiothoracic unit. PATIENTS AND METHODS: 23 consecutive children (14 male, nine female, mean age 3 years 2 months at surgery) who underwent resection of supravalvar mitral stenosis between 1978 and 1993. RESULTS: Follow up was for a mean of 58 months (range 0.5-167) after resection of supravalvar mitral stenosis. Four patients developed recurrent supravalvar mitral stenosis: this has not been reported previously. This was recognised 14-108 months after resection and confirmed at repeat operation. Three of these patients had successful reoperations but one died. Five other patients died. On multivariate analysis the only variable associated with survival free of recurrent supravalvar mitral stenosis was older age (18 months or more) at time of surgery (hazard ratio 0.17, 95% confidence interval (CI) 0.03 to 0.95, P < 0.05). Five year actuarial survival free of recurrent obstruction when supravalvar mitral stenosis was resected at age less than 18 months was only 39% (95% CI 9 to 69%) compared with 73% (95% CI 24 to 93%) in older patients. CONCLUSION: Supravalvar mitral stenosis is part of a spectrum of obstructive lesions affecting the left heart. Recurrent supravalvar mitral stenosis can develop after surgical resection. The prognosis in those who require resection within the first 18 months of life is poor: mortality is high, as is the risk of recurrent supravalvar mitral stenosis in survivors, probably because of continuing turbulent flow across a small left ventricular inflow tract.

Temporary iatrogenic fetal tricuspid valve atresia in a case of twin to twin transfusion syndrome.

This report describes the sequence of events in the development and subsequent spontaneous resolution of functional tricuspid valve atresia in the donor fetus in a case of twin to twin transfusion syndrome. Fetoscopic laser coagulation of the placental anastomoses was performed at 20 weeks' gestation. Subsequently, there was evidence of increased placental vascular resistance in the donor twin and major impairment of right ventricular function with no forward flow through the tricuspid valve. During the next four weeks, however, there was spontaneous and complete recovery of ventricular function and resolution of the functional tricuspid valve atresia. These findings suggest that alterations in fetal haemodynamics may result in structural cardiac abnormality and may be the precursors of some forms of congenital heart disease.

Thrombosis and embolism in long-term central venous access for parenteral nutrition.

Although the use of silicone catheters for long-term central venous access is widespread, little is known about the incidence of pulmonary thromboembolic complications. We studied clinical events, lung perfusion scans, and echocardiographic screens in 34 children and adolescents with gut failure who had received cyclical parenteral nutrition for 2 months to 9 years. Major thrombosis and/or embolism was identified in 12 patients and 4 died as a consequence. Actuarial survival free from thrombosis was 53% at 5 years (95% Cl, 30-77%). Survival free from fatal pulmonary thromboembolic events was 74% at 5 years (48-99%). 3 patients required surgery to remove right atrial thrombus or pulmonary emboli. Major right atrial thrombosis and pulmonary embolism are common and potentially fatal complications of parenteral nutrition by long-term venous access in childhood. Anticoagulation is recommended.

Late ventricular arrhythmia is rare after early repair of tetralogy of Fallot.

OBJECTIVES: This study was conducted to describe the incidence of ventricular arrhythmia during prospective long-term follow-up in a group of patients who had repair of tetralogy of Fallot during early childhood. BACKGROUND: Ventricular arrhythmia has been a common finding in patients who have undergone repair of tetralogy of Fallot in late childhood or as adults. Whether earlier repair lowers the incidence of late ventricular arrhythmia or late sudden death is unknown. METHODS: Twenty-nine asymptomatic patients who underwent repair at age 1.2 to 7.7 years (mean [+/- SD] age 4 +/- 1.4 years) between 1979 and 1984 were studied. Twenty-one patients had simple repair (Group A), and eight had complex or multiple operations (Group B). All had ambulatory electrocardiographic monitoring preoperatively, postoperatively, at early follow-up (after 4.2 +/- 1.3 years) and again at late follow-up (after 11.8 +/- 1.3 years). At late follow-up, 28 subjects also underwent echocardiography, and 26 had an exercise test. RESULTS: No patient had significant ventricular arrhythmia (> or = modified Lown grade 2) before or immediately after repair. There was no significant increase in the incidence of arrhythmia at early and late follow-up (14% to 28%), but at each of these periods the incidence of ventricular arrhythmia was higher in Group B patients (3 [43%] of 7 vs. 1 [5%] of 22 with early repair, p = 0.03; 6 [75%] of 8 vs. 2 [10%] of 21 with late repair, p = 0.001). No patient had symptoms of arrhythmia, and there were no sudden deaths. Late ventricular arrhythmia did not correlate with estimated right ventricular systolic pressure, outflow tract gradient or degree of pulmonary incompetence or right ventricular dilation. On exercise, 5 (19%) of 26 patients had ventricular premature complexes at low levels of exercise that were suppressed at maximal exercise in all patients. CONCLUSIONS: Late ventricular arrhythmia is rare in patients with successful early correction of tetralogy of Fallot, unless complex or multiple operations are performed.