Diagnosis of pentalogy of cantrell in the fetus using magnetic resonance imaging and ultrasound.

We report two cases of pentalogy of Cantrell diagnosed in utero using a combination of fetal echocardiography and magnetic resonance imaging. The cardiac component consisted of tetralogy of Fallot in the first fetus and ventricular septal defect in the second fetus. Whereas fetal echocardiography allowed accurate delineation of the cardiac anatomy, prenatal magnetic resonance imaging allowed clearer delineation of the extent of the thoracic and abdominal wall defects. Fetal magnetic resonance imaging in conjunction with prenatal echocardiography allows optimal assessment of the fetus with ectopia cordis, which has significant implications from the standpoint of preoperative planning and providing prognostic information. This report represents the first description of applying magnetic resonance imaging in combination with echocardiography toward a better understanding of this clinical entity in the fetus.

Safety and efficacy of intravenous contrast imaging in pediatric echocardiography.

This study was performed to determine the safety and efficacy of intravenous contrast echocardiography in children attending a tertiary cardiac center. This was a prospective study to evaluate the use of Optison contrast agent in children with severely limited transthoracic echocardiographic windows. Twenty children (median age, 15 years; range, 9-18) underwent fundamental imaging (FI), harmonic imaging (HI), and HI with intravenous contrast (Optison FS-069). Endocardial border delineation was determined based on a visual qualitative scoring system (0, none: 4, excellent). Endocardial border definition was significantly improved in all patients using contrast echocardiography (FI vs Optison, p < 0.001 for each). Improved border definition was most dramatic in the apical and left ventricular (LV) free wall regions. Left ventricular ejection fraction (LVEF) was measurable in 20 patients (100%) using contrast compared to 11 (55%) with FI or HI (p < 0.05). The echocardiographic diagnosis was correctly delineated in 1 patient with a severely dyskinetic LV segment only with use of intravenous contrast and HI. No patients suffered adverse hemodynamic effects, changes in taste, or flushing episodes. Three patients experienced transient headaches. Intravenous contrast echocardiography offers an additional tool in evaluating children with very poor transthoracic echocardiographic windows. Such a strategy increases diagnostic accuracy and allows accurate LVEF determination. Adverse hemodynamic effects related to intravenous contrast are exceedingly rare.

Echocardiographic predictors of adverse clinical events in children with dilated cardiomyopathy: a prospective clinical study.

OBJECTIVES: To compare tissue Doppler (TD) velocities between patients with dilated cardiomyopathy (DCM) and normal controls and to determine whether TD velocities, Tei index, right ventricular fractional area change, and left ventricular ejection fraction (LVEF) predict adverse clinical outcomes in children with DCM. METHODS: Prospective evaluation of children with DCM. RESULTS: 54 children with DCM and 54 age and sex matched control group participants were studied. Mitral inflow velocities were similar for both groups except for decreased mitral deceleration time in patients with DCM. Systolic and diastolic TD velocities at the mitral annulus (septal and lateral sides) and tricuspid annulus were significantly reduced in children with DCM compared with controls (p < 0.001 for each). By multivariate analysis, after adjustment for Tei index and right ventricular fractional area change, decreased LVEF and tricuspid velocity during early diastole (Ea) were predictors of the primary end point (PEP), a composite end point consisting of need for hospitalisation or the outcome transplantation or death. Tricuspid Ea velocity < 8.5 cm/s had 87% specificity and 60% sensitivity for reaching the PEP. LVEF < 30% had 68% specificity and 74% sensitivity for the PEP. Combined LVEF < 30% and tricuspid Ea < 11.5 cm/s had 100% specificity and 44% sensitivity for the PEP. CONCLUSIONS: Children with DCM have significantly lower TD velocities than normal controls. In such cases, lower LVEF (< 30%) is more sensitive but less specific than lower tricuspid Ea velocities (< 8.5 cm/s) in predicting which patients are at risk of hospitalisation, transplantation, or death.

Outcome of 121 patients with congenitally corrected transposition of the great arteries.

Congenitally corrected transposition of the great arteries (ccTGA) is a rare disorder with reduced survival that is influenced by the presence of associated anomalies, tricuspid regurgitation (TR), and right ventricular (RV) function. The double switch procedure has been proposed as an aggressive surgical approach in selected patients. We sought to review our experience with conventional repair to determine if a change in surgical strategy was warranted. Clinical records of 121 patients with ccTGA and two adequate-sized ventricles were retrospectively reviewed. Median length of follow-up was 9.3 years; 5-, 10-, and 20-year survival rates were 92%, 91%, and 75%, respectively. Surgery was performed in 86 patients, including conventional biventricular repair in 47 patients. Risk factors for mortality by univariate analysis included age at biventricular repair (p = 0.04), complete atrioventricular (AV) canal defect (p = 0.02), dextrocardia (p = 0.05), moderate or severe TR (p = 0.05), and poor RV function (p = 0.001). By multivariate analysis, complete AV canal defect (p = 0.006) and poor RV function (p = 0.002) remained significant as risk factors for mortality. Risk factors for the development of significant TR included conventional biventricular repair (p = 0.03) and complete AV block (p = 0.04). Risk factors for progressive RV dysfunction included conventional biventricular repair (p = 0.02), complete AV block (p = 0.001), and moderate or severe TR (p < 0.001). This is the largest nonselected cohort of patients with ccTGA followed at a single center. Our results confirm that significant TR and poor RV function are risk factors for poor outcome and provide convincing evidence that patients undergoing conventional biventricular repair are at higher risk for deterioration of tricuspid valve and right ventricular function compared to palliated or unoperated patients. We support a move toward an alternative surgical approach (double switch procedure) in carefully selected patients.

Natural history of growth of secundum atrial septal defects and implications for transcatheter closure.

OBJECTIVE: To investigate the natural history of secundum atrial septal defects (ASDs) over several years using serial echocardiographic studies. METHODS: All patients with isolated secundum ASDs who had serial transthoracic echocardiograms at Texas Children's Hospital, Houston, Texas, from January 1991 to December 1998 were identified. Patients with fenestrated or multiple ASDs, other congenital heart defects, or less than a six month interval between echocardiograms were excluded. There were 104 patients eligible for inclusion in the study. Studies were reviewed by two echocardiographers (blinded) and the maximal diameter was recorded. Defects were defined as small (> 3 mm to < 6 mm), moderate (> or = 6 mm to < 12 mm), or large (> or = 12 mm). ASDs that grew > or = 20 mm were defined as having outgrown transcatheter closure with the device available to the authors' institution. RESULTS: ASD diameter increased in 68 of 104 patients (65%), including 31 patients (30%) with a > 50% increase in diameter. Spontaneous closure occurred in four patients (4%). Thirteen defects (12%) increased to > or = 20 mm. One fifth of the patients studied had an insufficient atrial rim by transthoracic echocardiogram to hold an atrial septal occluder. The only factor associated with significant growth of ASDs was initial size of the defect. ASD growth was independent both of age at diagnosis and when indexed to body surface area. CONCLUSIONS: Two thirds of secundum ASDs may enlarge with time and there is the potential for secundum ASDs to outgrow transcatheter closure with specific devices. Further development in devices and general availability of devices capable of closing larger ASDs should circumvent this problem.

Perioperative care of the adult with congenital heart disease in a free-standing tertiary pediatric facility.

Adult patients with congenital heart disease are presenting more frequently for cardiac surgery. Frequently, pediatric congenital heart surgeons perform these procedures at pediatric hospitals. Between July 1995 and June 2000, a retrospective review of adult patients (> or = 18 years old) who had undergone cardiothoracic operations was performed. A total of 112 operations were performed and divided into two groups--81 cardiac operations in 79 patients and 31 noncardiac operations in 23 patients. One patient had a cardiac and noncardiac operation performed. The overall early operative mortality was 6% (6/101). There were 3 late deaths. New-onset cardiac arrhythmias requiring treatment were diagnosed after 5/81 (6%) cardiac operations. Six of 79 (7%) patients were diagnosed with postoperative clinical depression. An acceptable mortality can be achieved when adult patients undergo cardiothoracic operations at a pediatric facility. New-onset arrhythmias necessitating treatment are relatively common, and postoperative clinical depression should be anticipated.

Sizing of atrial septal defects to predict successful closure with transcatheter cardioSEAL device.

We conducted this retrospective study to compare methods for measuring atrial septal defects and to identify factors affecting echocardiographic measurement of such defects before transcatheter closure with the CardioSEAL'Septal Occluder. We reviewed the records of patients considered for device placement at our institution from January 1997 to April 1999. Atrial septal defect size was measured by transthoracic and transesophageal echocardiography; the stretched diameter was measured during catheterization by fluoroscopy and transesophageal echocardiography. The stretched-diameter fluoroscopic measurement was used for device size selection. Analysis of variance was used to calculate the effect of size, age, and size-by-age interaction. Thirty-one patients (3.3 to 72 years of age) underwent transthoracic and transesophageal echocardiography One patient was excluded from catheterization because of a 25-mm septal defect as indicated by transesophageal echocardiography (our maximum diameter, 15 mm). Thirty patients underwent transcatheter stretched-diameter sizing; 5 were excluded from device implantation because of defects >20 mm by stretched-diameter fluoroscopy (4) or septal length insufficient for device support (1). Implantation was successful in 23/25 patients; 2/23 had a residual shunt. In patients with available results (26/30), the stretched diameter was the same whether measured by stretched-diameter fluoroscopy or transesophageal echocardiography (P=0.007 R square=0.963). Compared with stretched-diameter fluoroscopy, precatheterization transthoracic and transesophageal echocardiography underestimated defect size by a mean of 22% and 13.2%, respectively. When data from those same tests were compared in defects of < or =0 mm and > 10 mm, transthoracic and transesophageal echocardiography were reliable predictors (P=0.003 and P=0.05, respectively) of stretched-diameter size in defects < or =0 mm.

Harmonic imaging in fetal echocardiography.

Noncontrast harmonic imaging (HI) has been shown to improve image quality in adults with poor acoustic windows. The utility of fetal echocardiography may be limited by suboptimal acoustic windows, and the use of HI in fetal echocardiography has not previously been defined. The purpose of this study was to compare the quality of fundamental imaging (FI) and HI in fetal echocardiography. Sixty-two fetal echocardiograms, including 44 (71%) with limited acoustic windows, were performed with the use of FI and HI. Image quality and visualization of the ventricles, valves, and the aortic and ductal arches were evaluated and compared between FI and HI. Mean HI scores were higher than mean FI scores for all the structures evaluated. Compared with FI, HI improved the image quality and visualization of cardiac structures in this group of fetuses with predominantly suboptimal acoustic windows. Harmonic imaging is a useful adjunct to FI in echocardiography, and the benefits of HI extend to cardiac imaging in the fetus.

Cardiac catheterization in diagnosis and management of congenital heart disease in thoracopagus conjoined twins.

Over the last two decades, surgical separation of thoracopagus conjoined twins has become increasingly feasible. Delineation of the degree of cardiac involvement is essential to establish the feasibility of surgical separation. We describe our experience of cardiac catheterization both in the diagnosis and management of nine sets of thoracopagus twins who presented to a single center over three decades and discuss its role in conjunction with other modern diagnostic modalities.

Double aortic arch in D-transposition of the great arteries: confirmation of dominant arch by magnetic resonance imaging.

We report the case of a female infant who had the rare combination of double aortic arch and D-transposition of the great arteries. The double aortic arch was diagnosed at the time of her arterial switch procedure. Magnetic resonance imaging identified the left arch as dominant, and the right arch was successfully ligated.

A controlled study of transesophageal echocardiography to guide central venous catheter placement in congenital heart surgery patients.

UNLABELLED: Transesophageal echocardiography (TEE) and central venous catheter (CVC) placement are often used during congenital cardiac surgery. Complications of CVC placement include cardiac perforation, inadvertent arterial placement, and erroneous hemodynamic data from unrecognized malposition. In this study, we used a prospective, randomized, controlled design to evaluate the use of TEE to guide depth of insertion and confirm superior vena cava cannulation, and to improve the percentage of correctly placed CVCs and reduce complications of CVC placement. One hundred forty-five patients were studied. Eighty patients were randomized to have subclavian vein insertion, 64 to have internal jugular insertion, and 1 to have external jugular insertion of CVC. TEE-guided CVC placement resulted in 100% correct placement when assessed by preoperative TEE, versus 86% in the control group (72 of 72 vs. 63 of 73; P = 0.01). There was no difference in correct placement between the two groups when assessed by postoperative chest radiograph (81.9% TEE versus 75.3% control; P = not significant). One significant complication, a superior vena cava perforation, occurred in the control group. Time to placement was 9.6 min in the TEE group versus 8.0 min in the control group (P = 0.015). IMPLICATIONS: Transesophageal echocardiography can be used to guide central venous catheter placement in congenital heart surgery. Central venous catheters that seem to be located high in the right atrium by chest radiograph in these patients are often actually in the superior vena cava and pose little risk of cardiac perforation.

Outcome of pregnancy following intervention for coarctation of the aorta.

There are limited data regarding the outcome of pregnancy in women after intervention for coarctation of the aorta (CoA). The Texas Children's Hospital Cardiac Database was used to identify female patients with CoA born before 1980 who had undergone balloon angioplasty or surgery. Patients with Turner's syndrome and cyanotic congenital heart disease were excluded. A chart review and telephone interview were performed. Data collected included age at intervention, type of intervention, the need for reintervention, functional status, number of pregnancies, and pregnancy outcomes. Seventy-four patients met our criteria and we were able to contact 52. Eighteen patients (39%) were pregnant a total of 36 times. There were 3 spontaneous and 4 elective abortions. Preeclampsia complicated 4 pregnancies in 3 women (17% of primigravidas). One patient had systemic hypertension. Eleven infants were delivered by Cesarean section. There were 29 births, with an average weight of 3.0 kg. There were 5 preterm births, 4 to a teenage mother. Only 1 child (3%) had a congenital heart defect. Thus, in women with an arm-to-leg blood pressure gradient of <20 mm Hg after CoA repair, pregnancy is successful. The occurrence of congenital heart disease in the offspring was 3%. Preeclampsia was similar to that in the general population.

Development and validation of an echocardiographic model for predicting progression of discrete subaortic stenosis in children.

The clinical course of discrete subaortic stenosis (DSS) varies considerably between patients. This study was performed to identify echocardiographic characteristics of DSS that distinguish progressive from nonprogressive disease. The study included 100 patients from 2 institutions and was performed in 2 stages. In phase I, a prediction model was developed based on multivariate analysis of morphometric and Doppler variables obtained from the initial echocardiogram in 52 children with DSS from Texas Children's Hospital. In phase II, the performance characteristics of the prediction model were tested in 48 patients with DSS followed at Children's Hospital in Boston. Patients were divided into 3 outcome groups: nonprogressive, progressive, and intermediate progression. In phase I, multivariate analysis identified 3 independent predictors of progressive disease: indexed aortic valve to subaortic membrane distance, anterior mitral leaflet involvement, and initial Doppler gradient. The logistic regression equation--Probability = [1 + e-(-322+0.334X1+4.06X2-0.708X3)](-1), where X = initial gradient in mm Hg; X2 = absence (0) or presence (1) of mitral leaflet involvement; and X3 = indexed distance between aortic valve and subaortic membrane in mm/body surface area0.5 were used to predict progression. When the prediction model was applied to phase II study patients, none of the patients with nonprogressive DSS had a prediction value > 0.29 and none of the patients with progressive DSS had a prediction value < 0.58. Thus, a prediction value > 0.55 yielded a 100% sensitivity and 100% specificity for distinguishing progressive from nonprogressive DSS. Patients with intermediate progression were indistinguishable from progressive DSS but were clearly separable from nonprogressing patients. We conclude that progressive subaortic obstruction in children with DSS can be predicted from morphologic, morphometric, and Doppler echocardiographic analysis of left ventricular outflow.

Update on new technologies in pediatric echocardiography.

Advances in ultrasound technology will continue to expand the utility of echocardiography in the assessment of structural and functional cardiac disease in children. Tissue Doppler imaging and dobutamine stress echocardiography are 2 promising clinical applications that are expected to become increasingly used with time. Advances in data compression technology, including JPEG and MPEG techniques, will significantly affect digital archival and transmission of echocardiograms, which also have clinical implications, particularly in the expanding use of telemedicine. Continued research and clinical experience will further define the ultimate roles of these technologies in the future.

Advances in acquired pediatric heart disease.

Acquired heart disease in children may result in significant morbidity and mortality. Advances continue to be made in understanding Kawasaki disease, acute and chronic rheumatic heart disease, infective endocarditis, myocarditis, and dilated cardiomyopathy. The role of superantigens, particularly bacterial toxins, in the pathogenesis of Kawasaki disease continues to be defined. Intravascular ultrasound promises to improve the assessment of coronary arteries in Kawasaki disease. Current recommendations for the long-term management of Kawasaki disease are discussed. Significant changes in the epidemiology of acute rheumatic fever and endocarditis are noted. Updates on the role of echocardiography as well as current therapeutic issues in these diseases are addressed. The application of immunologic and molecular biologic techniques have implicated genetic and immune factors in the pathogenesis of myocarditis and cardiomyopathy. The relationship between viral infection and subsequent dilated cardiomyopathy, as well as the role of autoimmune mechanisms in the pathogenesis of these disorders, remains controversial.

Acquired heart disease in children.

Recent advances have been made in understanding Kawasaki disease, acute rheumatic fever and rheumatic heart disease, cardiomyopathy, and acquired immunodeficiency syndrome. Immune-mediated tissue injury in Kawasaki disease is likely caused by response to a superantigen. Persistent functional and anatomic coronary abnormalities may lead to silent ischemia and increase the risk of early atherosclerotic heart disease. Intravenous immunoglobulin therapy is clearly beneficial, but specific therapy awaits further definition of the etiology and pathophysiology of Kawasaki disease. Recently updated diagnostic criteria for Kawasaki disease and acute rheumatic fever are discussed. Advances in the understanding of genetically determined abnormal immune responses to streptococcal pharyngitis may help explain acute rheumatic fever manifestations. Further advances have been made in the elucidation of the pathophysiology of cardiomyopathy, particularly the role of viruses and genetic factors. Angiotensin-converting enzyme inhibitors appear to improve survival in dilated cardiomyopathy. Controversy regarding the possible myocardial depressant effect of zidovudine in human immunodeficiency virus infection is discussed.

Glycerol oxidation in discrete areas of rat brain from young, adolescent, and adult rats.

We have reported previously that the oxidation rate of [1,3-14C] glycerol to 14CO2 is lower in whole brain homogenates from neonatal rats and increases about 30% during the suckling period to adult levels. To determine whether there are developmental changes in glycerol oxidation in discrete regions of brain, we examined the oxidation of glycerol by homogenates of hypothalamus, cerebellum, brain stem, hippocampus, and cerebral cortex of young (4-6 days) and older (18-20 days) pups and adult (greater than 90 day) rats. The oxidation was measured at both low (0.2 mM) and high (2.0 mM) concentrations of glycerol, since the oxidation of glycerol by brain tissue has been shown to exhibit biphasic kinetics. At each age, and with both concentrations of glycerol, there were significant differences among the discrete brain regions. Although the rate of glycerol oxidation increased with age in most areas of brain, each brain region had a distinct developmental profile. In the hypothalamus, the oxidation of glycerol increased significantly between 4-6 days and adult levels at 18-20 days. The oxidation of glycerol was essentially the same in homogenates of cortex from young and older pups, but it was significantly increased in adults. In contrast with other brain regions, the oxidation of glycerol by brain stem was highest at 4-6 days and significantly decreased with age. The developmental profile of glycerol oxidation in hippocampus and cerebellum was particularly complex, since it increased with age at low, but not at high, concentrations of glycerol. This developmental pattern in hippocampus and cerebellum could be related to changes in the biphasic kinetics of glycerol oxidation and suggests that glycerol metabolism is different in these two areas of brain compared with other areas of brain.

Competition of glycerol with other oxidizable substrates in rat brain.

The rate of conversion of [1,3-14C]glycerol into 14CO2 was measured in the presence and absence of unlabelled alternative substrates in whole homogenates from the brains of young (4-6 and 18-20 days old) and adult rats. Unlabelled glucose decreased 14CO2 production from [1,3-14C]glycerol by about 40% at all ages studied. Unlabelled 3-hydroxybutyrate significantly decreased the 14CO2 production from both low (0.2 mM) and high (2.0 mM) concentrations of glycerol in 4-6- and 18-20-day-old rat pups. However, the addition of 3-hydroxybutyrate had no effect on the rate of 14CO2 production from 2.0 mM-glycerol in adult rats, suggesting that the interaction of 3-hydroxybutyrate with glycerol in adult rat brain is complex and may be related to the biphasic kinetics previously reported for glycerol oxidation. Unlabelled glutamine decreased the production of 14CO2 by brain homogenates from 18-20-day-old and adult rats, but not in 4-6-day-old rat pups. In the converse situation, the addition of unlabelled glycerol to whole brain homogenates had little effect on the rate of 14CO2 production from [6-14C]glucose, 3-hydroxy[3-14C]butyrate and [U-14C]glutamine, although some significant differences were noted. Collectively these results suggest that glycerol and these other substrates may be metabolized in separate subcellular compartments in brain such that the products of glucose, 3-hydroxybutyrate and glutamine metabolism can dilute the oxidation of glycerol, but the converse cannot occur. The data also demonstrate that there are complex age-related changes in the interaction of glycerol with 3-hydroxybutyrate and glutamine. The fact that glycerol oxidation was only partially suppressed by the addition of 1-5 mM-glucose, -3-hydroxybutyrate or -glutamine could also suggest that glycerol may be selectively utilized as an energy substrate in some discrete brain region.