Fetal Diagnosis of Dextroposition, Left Pulmonary Artery Sling, Partial Anomalous Left Pulmonary Artery, and Aortic Coarctation

•LPA sling is a rare anomaly definable by fetal echocardiography. •LPA sling is frequently associated with significant respiratory morbidity and mortality. •Fetal diagnosis should prompt planning for postnatal management at a pediatric center. •We present a fetal case of dextroposition, partial LPA sling, and aortic coarctation. •Progressive dextroposition was an indicator for the presence of an LPA sling.

Effects of Transplacental Dexamethasone Therapy on Fetal Immune-Mediated Complete Heart Block

INTRODUCTION

Antibody-mediated complete atrioventricular block (CAVB) is considered irreversible. We sought to examine the effects of transplacental steroids on fetal AV conduction.

METHODS

Fifty-nine fetuses diagnosed with CAVB at our center from 1996 to 2018 were reviewed. Routine dexamethasone administration to birth was used to limit cardiac inflammatory damage. Restoration of fetal AV conduction was classified as "unexpected" treatment response.

RESULTS

CAVB resolved in 5/29 (17%) fetuses first treated ≤24-week gestation with 8 mg/day of dexamethasone, when compared with 0/30 (0%) when treatment was initiated later and/or at a starting dose of 4 mg/day (odds ratio 13.69; 95% confidence interval 0.72-260.13; p = 0.024). Treatment response was also associated with a faster ventricular rate at diagnosis (median [range]: 80 [60-97] beats per minute [bpm] vs. 58 [38-92] bpm; p = 0.0036). CAVB reappeared in all 5 responders either prenatally (n = 1) or postnatally before (n = 3) or after (n = 1) the first year of life. When compared with infants with treatment-resistant CAVB (median follow-up 10.3 years), responders (median follow-up 12.3 years) required postnatal pacing less frequent (2/5 [40%] vs. 45/49 [92%]; p = 0.013).

CONCLUSIONS

In a subgroup of CAVB fetuses, dexamethasone transiently restored AV conduction. This was associated with a lower rate of postnatal pacing when compared with nonresponders.

Systematic Approach to Malalignment Type Ventricular Septal Defects

Various congenital heart diseases are associated with malalignment of a part of the ventricular septum. Most commonly, the outlet septum is malaligned toward the right or left ventricle. Less commonly, the whole or a major part of the ventricular septum is malaligned in relation to the atrial septal plane. Although the pathological conditions associated with ventricular septal malalignment have been well recognized, the descriptions are often confusing and sometimes incorrect. In this pictorial essay, we introduce our systematic approach to the assessment of malalignment type ventricular septal defects with typical case examples. The systematic approach comprises description of the essential features of malalignment, including the following: (1) the malaligned part of the ventricular septum, (2) the reference structure, (3) the mechanism of malalignment, (4) the direction of malalignment, and (5) the severity of malalignment.

Treatment of fetal circular shunt with non-steroidal anti-inflammatory drugs

A circular shunt (CS) is a life-threatening condition involving massive shunting of systemic arterial blood via the ductus arteriosus to the left ventricle without traversing the lungs. In the prenatal setting, it occurs mainly in fetuses with severe forms of Ebstein's anomaly (EA) owing to unrestricted ductal flow and significant pulmonary and tricuspid regurgitation. We aimed to improve the fetal hemodynamics and chances of survival of affected fetuses by inducing ductal constriction using transplacental non-steroidal anti-inflammatory drugs (NSAIDs). Following initiation of treatment between 26 and 34 weeks' gestation, three (75%) of four fetuses with EA/CS responded with sustained ductal constriction and improved hemodynamic function, which allowed continuation of pregnancy for 3-7 weeks and elective delivery. All successfully treated cases underwent neonatal surgery immediately after birth to eliminate the CS and survived. This included two neonates that underwent single-ventricle palliation surgery that required postoperative extracorporeal membrane oxygenation and hemofiltration for transient respiratory and renal failure. The one case that did not respond to treatment with NSAIDs was delivered prematurely for progressive fetal compromise and died shortly after birth. Transplacental treatment with NSAIDs represents a novel approach to controlling fetal CS, avoiding in-utero death and prolonging the pregnancy to a more advanced gestational age, thereby potentially increasing the chances of neonatal survival. This treatment should be considered and initiated at an early stage of systemic steal to prevent brain injury due to hypoperfusion. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Improving Prenatal Diagnosis of Coarctation of the Aorta

BACKGROUND

The purpose of the study was to evaluate the association between fetal echocardiographic measurements and the need for intervention (primary coarctation repair, staged coarctation repair, or catheter intervention) in prenatally diagnosed coarctation of the aorta.

METHODS

A single-centre retrospective cohort study (2005-2015) of 107 fetuses diagnosed with suspected coarctation of the aorta in the setting of an apex-forming left ventricle and antegrade flow across the mitral and aortic valves.

RESULTS

Median gestational age at diagnosis was 32 weeks (interquartile range, 23-35 weeks). Fifty-six (52%) did not require any neonatal intervention, 51 patients (48%) underwent a biventricular repair. In univariable analysis, an increase in ascending aorta (AAo) peak Doppler flow velocity (odds ratio [OR], 1.40 [95% confidence interval [CI], 1.05-1.91] per 20 cm/s; P = 0.03) was associated with intervention. No intervention was associated with larger isthmus size (OR, 0.23; P < 0.001), transverse arch diameter (OR, 0.23; P < 0.001), and aortic (OR, 0.72; P = 0.02), mitral (OR, 0.58; P = 0.001), and AAo (OR, 0.53; P < 0.001) z-scores. In multivariable analysis, higher peak AAo Doppler (OR, 2.51 [95% CI, 1.54-4.58] per 20 cm/s; P = 0.001) and younger gestational age at diagnosis (OR, 0.81 [95% CI, 0.70-0.93] per week; P = 0.005) were associated with intervention, whereas a higher AAo z-score (OR, 0.65 [95% CI, 0.43-0.94] per z; P = 0.029) and transverse arch dimension (OR, 0.44 [95% CI, 0.18-0.97]; P = 0.05) decreased the risk of intervention.

CONCLUSIONS

In prenatally suspected coarctation, the variables associated with intervention comprised smaller AAo and transverse arch size, earlier gestational age at diagnosis, and the additional finding of a higher peak AAo Doppler.

Contemporary Outcomes and Factors Associated With Mortality After a Fetal or Postnatal Diagnosis of Common Arterial Trunk

BACKGROUND

Common arterial trunk (CAT) is a rare anomaly with a spectrum of pathology. We sought to identify current trends and factors associated with postnatal outcomes.

METHODS

This was a single-centre review including 153 live births with planned surgery. Patients were analyzed as 2 cohorts based on era of CAT diagnosis (1990 to 1999 vs 2000 to 2014) and complexity of disease (simple vs complex). "Complex" required the association with significant aortic arch obstruction, truncal valve (TV) stenosis/regurgitation, and/or branch pulmonary artery (PA) hypoplasia, respectively.

RESULTS

Sixteen (10%) died preoperatively, and this outcome was associated with significant TV stenosis (odds ratio [OR] 4.55; P = 0.01) and regurgitation (OR 3.17; P = 0.04); 130 (95%) of 137 operated infants underwent primary complete repair. Their survival rates to 1 year improved from 54% to 85% after 2000, although this outcome remained substantially lower for cases with a complex vs simple CAT repair (76% vs 95%; OR 6.46; P = 0.006). Other risk factors associated with decreased 1-year survival included diagnosis before 2000 (OR 4.48; P = 0.038) and a lower birth weight (OR 8.0 per kg weight; P = 0.001). Finally, of 93 survivors beyond year 1 of life, 76 (82%) had undergone a total of 224 reinterventions. Only 15 (16%) were alive without any surgical or catheter-based reintervention at study end.

CONCLUSIONS

Despite recent surgical improvements, postnatal mortality continues to be substantial if CAT is complicated by significant pathology of the TV, aortic arch, or branch PAs. Reoperations and catheter interventions are eventualities for most patients during childhood.

Reproducibility of Left Ventricular Dimension Versus Area Versus Volume Measurements in Pediatric Patients With Dilated Cardiomyopathy

BACKGROUND

Multiple echocardiographic methods are used to measure left ventricular size and function. Clinical management is based on individual evaluations and longitudinal trends. The Pediatric Heart Network VVV study (Ventricular Volume Variability) in pediatric patients with dilated cardiomyopathy has reported reproducibility of several of these measures, and how disease state and number of beats impact their reproducibility. In this study, we investigated the impact of observer and sonographer variation on reproducibility of dimension, area, and volume methods to determine the best method for both individual and sequential evaluations.

METHODS AND RESULTS

In 8 centers, echocardiograms were obtained on 169 patients prospectively. During the same visit, 2 different sonographers acquired the same imaging protocol on each patient. Each acquisition was analyzed by 2 different observers; first observer analyzed the first acquisition twice. Intraobserver, interobserver, interacquisition, and interobserver-acquisition (different observers and different acquisition) reproducibility were assessed on measurements of left ventricular end-diastolic dimension, area, and volume. Left ventricular shortening fraction, ejection fraction, mass, and fractional area change were calculated. Percent difference was calculated as (interobservation difference/mean)×100. Interobserver reproducibility for both acquisitions was better for both volume and dimension measurements (P≤0.002) compared with area measurements, whereas intraobserver, interacquisition (for both observers), and interobserver-acquisition reproducibilities (for both observer-acquisition sets) were best for volume measurements (P≤0.01). Overall, interobserver-acquisition percent differences were significantly higher than interobserver and interacquisition percent differences (P<0.001).

CONCLUSIONS

In pediatric patients with dilated cardiomyopathy, compared with dimension and area methods, left ventricular measurements by volume method have the best reproducibility in settings where assessment is not performed by the same personnel.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT00123071.

Utility of feed-and-sleep cardiovascular magnetic resonance in young infants with complex cardiovascular disease

Utilization of cardiovascular magnetic resonance (CMR) is limited in young children because of the need for sedation or general anesthesia (GA). It has been previously shown that CMR can be performed without sedation or GA in young infants who are prone to fall asleep after being fed and swaddled. The purpose of this study was to prospectively prove the feasibility of the feed-and-sleep CMR technique in larger cohorts in the two institutions where the technique was initially developed. This was a prospective dual-center cohort study over a two-year period. All infants younger than 6 months old with complex congenital cardiovascular anomaly who required CMR were recruited for this study. The exclusion criteria included mechanical ventilation, oxygen dependence, feeding difficulties, and any contraindication to CMR. The feed-and-sleep study was performed by fasting the infant for a period of 4 h prior to the scan, placing the infant in a vacuum immobilizer, and feeding the infant just prior to the CMR. The CMR sequences were prioritized to target the area of most importance first. A study was considered complete and diagnostic if the clinical question was answered. A total of 60 infants (39 from center A and 21 from center B) were recruited for this study, 32 male and 28 female, ages ranging from 1 to 177 days (50 ± 54). The CMR studies were diagnostic and answered the clinical questions in all patients. All infants tolerated the procedure well, and no complications were noted in any of the patients. The CMR duration ranged between 4-132 minutes (45 ± 21). The feed-and-sleep approach in selected patients obviates the need of sedation or GA for CMR in infants younger than 6 months old. Therefore, CMR can be utilized whenever echocardiography fails to provide the complete information required for the patients' management.

The reproducibility and absolute values of echocardiographic measurements of left ventricular size and function in children are algorithm dependent

BACKGROUND

Several quantification algorithms for measuring left ventricular (LV) size and function are used in clinical and research settings. The aims of this study were to investigate the effects of measurement algorithm and beat averaging on the reproducibility of measurements of the left ventricle and to assess the magnitude of agreement among the algorithms in children with dilated cardiomyopathy.

METHODS

Echocardiograms were obtained in 169 children from eight clinical centers. Inter- and intrareader reproducibility was assessed on measurements of LV volumes using the biplane Simpson, modified Simpson, and 5/6 × area × length (5/6AL) algorithms. Percentage error was calculated as inter- or intrareader difference/mean × 100. Single-beat measurements and the three-beat average (3BA) were compared. Intraclass correlation coefficients were calculated to assess agreement.

RESULTS

Single-beat interreader reproducibility was lowest (percentage error was highest) using biplane Simpson; 5/6AL and modified Simpson were similar but significantly better than biplane Simpson (P < .05). Single-beat intrareader reproducibility was highest using 5/6AL (P < .05). The 3BA improved reproducibility for almost all measures (P < .05). Reproducibility in both single-beat and 3BA values fell with greater LV dilation and systolic dysfunction (P < .05). Intraclass correlation coefficients were >0.95 across measures, although absolute volume and mass values were systematically lower for biplane Simpson compared with modified Simpson and 5/6AL.

CONCLUSIONS

The reproducibility of LV size and functional measurements in children with dilated cardiomyopathy is highest using the 5/6AL algorithm and can be further improved by using the 3BA. However, values derived from different algorithms are not interchangeable.

Spectrum and outcome of primary cardiomyopathies diagnosed during fetal life

OBJECTIVES

The purpose of this study was to determine the phenotypic presentation, causes, and outcome of fetal cardiomyopathy (CM) and to identify early predictors of outcome.

BACKGROUND

Although prenatal diagnosis is possible, there is a paucity of information about fetal CM.

METHODS

This was a retrospective review of 61 consecutive fetal cases with a diagnosis of CM at a single center between 2000 and 2012.

RESULTS

Nonhypertrophic CM (NHCM) was diagnosed in 40 and hypertrophic CM (HCM) in 21 fetuses at 24.7 ± 5.7 gestational weeks. Etiologies included familial (13%), inflammatory (15%), and genetic-metabolic (28%) disorders, whereas 44% were idiopathic. The pregnancy was terminated in 13 of 61 cases (21%). Transplantation-free survival from diagnosis to 1 month and 1 year of life for actively managed patients was better in those with NHCM (n = 31; 58% and 58%, respectively) compared with those with HCM (n = 17; 35% and 18%, respectively; hazard ratio [HR]: 0.44; 95% confidence interval [CI]: 0.12 to 0.72; p = 0.007). Baseline echocardiographic variables associated with mortality in actively managed patients included ventricular septal thickness (HR: 1.21 per z-score increment; 95% CI: 1.07 to 1.36; p = 0.002), cardiothoracic area ratio (HR: 1.06 per percent increment; 95% CI: 1.02 to 1.10; p = 0.006), ≥3 abnormal diastolic Doppler flow indexes (HR: 1.44; 95% CI: 1.07 to 1.95; p = 0.02), gestational age at CM diagnosis (HR: 0.91 per week increment; 95% CI: 0.83 to 0.99; p = 0.03), and, for fetuses in sinus rhythm, a lower cardiovascular profile score (HR: 1.45 per point decrease; 95% CI: 1.16 to 1.79; p = 0.001).

CONCLUSIONS

Fetal CM originates from a broad spectrum of etiologies and is associated with substantial mortality. Early echocardiographic findings appear useful in predicting adverse perinatal outcomes.

Variability of M-mode versus two-dimensional echocardiography measurements in children with dilated cardiomyopathy

M-mode and 2-dimensional (2D) echocardiographic imaging are routinely used to quantify left-ventricular (LV) size and function in pediatric patients with dilated cardiomyopathy (DCM). The reproducibility of and correlation between these techniques are unknown. This analysis sought to compare interreader, intrareader, and interacquisition reproducibility of M-mode versus 2D measurements in pediatric DCM patients. The Ventricular Volume Variability study of the Pediatric Heart Network is a multicenter, prospective, observational study assessing the course of chronic DCM in children. Two sonographers performed baseline image acquisitions locally, and two readers performed measurements at the echocardiographic core laboratory. One reader repeated measurements 1 month later. These data were used to assess reproducibility and agreement between M-mode and 2D measurements. One hundred sixty-nine subjects were enrolled. M-mode had similar or greater reproducibility in both intrareader and interreader settings for LV dimensions, shortening fraction (SF), and most wall thicknesses. In contrast, 2D reproducibility was similar or better for nearly all variables in the interacquisition setting but not for SF. Interacquisition variability was approximately twice the intrareader variability. LV dimensions by either modality consistently had high reproducibility and had the highest agreement between modalities. In pediatric DCM patients, variability of linear echocardiographic assessment could be minimized by relying on a single reader and using a consistent method (M-mode or 2D) for serial measurements, preferably M-mode when SF is the primary variable of interest. Except for LV dimensions, M-mode and 2D values should not be used interchangeably due to poor agreement.

The ventricular volume variability study of the Pediatric Heart Network: study design and impact of beat averaging and variable type on the reproducibility of echocardiographic measurements in children with chronic dilated cardiomyopathy

BACKGROUND

Clinical trials often rely on echocardiographic measures of left ventricular size and function as surrogate end points. However, the quantitative impact of factors that affect the reproducibility of these measures is unknown. To address this issue, the National Heart, Lung, and Blood Institute-funded Pediatric Heart Network designed a longitudinal observational study of children with known or suspected dilated cardiomyopathy aged 0 to 22 years from eight pediatric clinical centers.

METHODS

Clinical data were collected together with 150 echocardiographic indices of left ventricular size and function. Separate observers performed duplicate echocardiographic imaging. Multiple observers performed measurements from three cardiac cycles to enable assessment of intraobserver and interobserver variability. The impacts of beat averaging (BA), observer type (local vs core), and variable type (areas, calculations, dimensions, slopes, time intervals, and velocities) on measurement reproducibility were studied. The outcome measure was percentage error (100 × difference/mean).

RESULTS

Of 173 enrolled subjects, 131 met criteria for dilated cardiomyopathy. BA, variable type and observer type all influenced percentage error (P < .0001). Core interobserver percentage error (medians, 11.4%, 10.2%, and 9.3% for BA using one, two, and three beats, respectively) was approximately twice the intraobserver percentage error (medians, 6.3%, 4.9%, and 4.2% for BA using one, two, and three beats, respectively). Slopes and calculated variables exhibited high percentage error despite BA. Chamber dimensions, areas, velocities, and time intervals exhibited low percentage error.

CONCLUSIONS

This comprehensive evaluation of quantitative echocardiographic methods will provide a valuable resource for the design of future pediatric studies. BA and a single core lab observer improve the reproducibility of echocardiographic measurements in children with dilated cardiomyopathy. Certain measurements are highly reproducible, while others, despite BA, are poorly reproducible.

Utility of contrast echocardiography for pulmonary arteriovenous malformation screening in pediatric hereditary hemorrhagic telangiectasia

OBJECTIVE

To evaluate the utility of transthoracic contrast echocardiography (TTCE) as a screening tool for pulmonary arteriovenous malformations (PAVMs) in children with hereditary hemorrhagic telangiectasia (HHT).

STUDY DESIGN

This was a single-center study of children who underwent baseline screening for PAVMs using both TTCE and chest computed tomography (CT) for evaluation of HHT. The CT and TTCE results were prospectively reviewed independently by 2 radiologists and 2 cardiologists blinded to the study results.

RESULTS

Both intraobserver and interobserver agreement for interpreting TTCE results were excellent (κ = 0.97 and 0.92, respectively) and higher than the interobserver agreement for CT interpretation (κ = 0.75). The sensitivity and specificity of TTCE to predict PAVMs were 1 and 0.82, respectively, and the positive predictive and negative predictive values were 0.39 and 1, respectively.

CONCLUSION

TTCE is a sensitive test for PAVMs in children with suspected HHT and can be a useful initial screening tool in pediatric HHT.

Challenges in echocardiographic assessment of mitral regurgitation in children after repair of atrioventricular septal defect

The validity and reproducibility of echocardiographic methods used to quantify mitral regurgitation (MR) in children with congenital heart disease are unknown. We evaluated the usefulness of methods used to quantify MR in children enrolled in a multicenter trial of enalapril 6 months after surgical repair of an atrioventricular septal defect (AVSD). MR severity in this trial was assessed using body surface area (BSA)-adjusted vena contracta lateral (i-VCW(lat)) and anterior-posterior (i-VCW(ap)) dimensions and cross-sectional area (i-VCA), regurgitant volume/BSA, regurgitant fraction, and qualitative MR grade. For each method, association with left ventricular end-diastolic volume (LVEDVz) and end-diastolic dimension (LVEDDz) z-scores and interobserver agreement were assessed. In 149 children (median age 1 year), i-VCW(lat), i-VCW(ap), and i-VCA were best associated with LVEDVz (r (2) = 0.54, r (2) = 0.24, and r (2) = 0.46, respectively; p < 0.001 for all) and showed the highest interobserver agreement (intraclass correlation coefficient = 0.62, 0.73, and 0.68, respectively). Qualitative MR grade was also associated with LVEDVz (r (2) = 0.31, p < 0.001) and showed modest interobserver agreement (kappa 0.56). Regurgitant volume/BSA and regurgitant fraction were associated with LVEDVz (r (2) = 0.45 and r (2) = 0.45, p < 0.001 for both) but showed poor interobserver agreement [ICC = 0.28 (n = 91) and ICC = 0.17 (n = 76), respectively], and their values were negative in 75% of subjects. In conclusion, echocardiographic assessment of MR severity after AVSD remains challenging. Among the quantitative methods used in this trial, i-VCW and i-VCA performed the best but offered little advantage compared with qualitative MR grade. The utility of regurgitant volume and fraction was severely limited by poor interobserver agreement and frequently negative values.

Characteristics and outcomes of double outlet left ventricle

BACKGROUND

Double outlet left ventricle (DOLV) is a rare cardiac malformation in which both great arteries originate from the morphological left ventricle. There are limited data regarding the anatomical spectrum, characteristics and outcomes of DOLV.

METHODS

All patients with DOLV between 1960 and 2008 were identified. Patients' presentation, anatomy, surgical history, and outcomes were recorded. Kaplan-Meier estimates were used to describe time-related survival and freedom from surgical intervention.

RESULTS

There were 19 patients with DOLV during the study period, 14 of whom were male (74%). Median age at presentation was 2 days (birth--5.5 years). The most prominent associated cardiac morphologies (in addition to DOLV) were atrial septal defects (14, 74%), ventricular septal defects (13, 68%), right ventricular hypoplasia (12, 63%), and patent ductus arteriosus (15, 80%). At presentation, nine patients (47%) were cyanosed, nine (42%) had cardiomegaly, and all had some degree of right ventricular dysfunction. Of the 19 patients, seven underwent biventricular repairs, nine underwent univentricular palliations, one had only palliative care, and two were seen for consultation only. There were six deaths in this series, five were cardiac in nature (one due to genetic syndrome). Five-year survival after presentation for both biventricular and univentricular repairs was 70-75% (P= 0.80). Most surviving patients had residual cardiac abnormalities at last follow-up despite surgical repair.

DISCUSSION

DOLV is a rare cardiac malformation associated with high mortality and guarded outcomes from residual lesions.

Lessons learned from a pediatric clinical trial: the Pediatric Heart Network angiotensin-converting enzyme inhibition in mitral regurgitation study

BACKGROUND

Mitral regurgitation is the most common indication for reoperation in children following repair of atrioventricular septal defect (AVSD). We hypothesized that angiotensin-converting enzyme inhibitor therapy would decrease the severity of mitral regurgitation and limit left ventricular volume overload in children following AVSD repair.

METHODS

The Pediatric Heart Network designed a placebo-controlled randomized trial of enalapril in this population. The primary aim was to test the effect of enalapril on the change in left ventricular end-diastolic dimension body surface area-adjusted z score. Before the launch of the trial, a feasibility study was performed to estimate the number of patients with at least moderate mitral regurgitation following AVSD repair.

TRIAL EXPERIENCE

Seventeen months after the start of the study, 349 patients were screened, 8 were trial eligible, and only 5 were enrolled. The study was subsequently terminated because of low patient accrual. Several factors led to the problems with patient accrual, including (1) the use of criteria to assess disease severity in the feasibility study that were not identical to those used in the trial, (2) failure to achieve equipoise for the study among clinicians and referring physicians, (3) reliance on methodology developed in adult populations with different disease mechanisms, and (4) absence of adequate data to define the natural history of the disease process under study. Progress in the treatment of children with cardiovascular disease will depend on the future of multicenter collaborative clinical trials. The lessons learned from this study may contribute to improvements in this research.

Improved classification of coronary artery abnormalities based only on coronary artery z-scores after Kawasaki disease

Competing definitions and classifications of coronary artery abnormalities (CAAs) after Kawasaki disease (KD) have been arbitrarily defined based on clinical experience. We sought to propose a classification system for CAAs based only on coronary artery z-scores. All echocardiograms performed between 1990 and 2007 on patients with a previous history of KD were reviewed. Coronary artery luminal dimensions were converted to body-surface-area-adjusted z-scores and compared to current classification systems. A total of 1356 patients with a previous history of KD underwent 4379 echocardiograms. There was important overlap in the distributions of coronary artery z-scores between the different CAA classes as defined by the American Heart Association (AHA). The AHA classification underestimated the severity of CAAs in 19-32% of small CAAs and 35-78% of medium CAAs. We determined the optimal definition of CAA to be small if the z-score is >or=2.5 to <5.0, large if the z-score is >or=5.0 to <10.0, and giant if the z-score is >or=10.0. This classification seems to appropriately apply to the circumflex branch despite a lack of normal values for this branch. The current AHA classification might not accurately classify CAAs in KD patients. Accurate classification is important for defining management and prognosis consistently across patient age and size.

Intraoperative coronary artery pulse Doppler patterns in patients with complete transposition of the great arteries undergoing the arterial switch operation

BACKGROUND

Arterial switch operation is standard repair for complete transposition of the great arteries (TGA). Coronary artery abnormalities are the most common cause of morbidity and mortality in the acute postoperative phase. This study was designed to determine whether coronary artery pulse Doppler flow patterns obtained by transesophageal echocardiography during the arterial switch operation are correlated with acute postoperative outcomes.

METHODS

A retrospective review of all patients with TGA undergoing the arterial switch operation between 2004 and 2006 was performed. Intraoperative coronary artery pulse Doppler flow patterns were analyzed by 2 blinded investigators. Associations of coronary artery pulse Doppler flow patterns with clinical outcomes were sought using multivariable linear and logistic regression analysis.

RESULTS

Sixty-three patients (48 male, gestational age 38 +/- 2 weeks, birth weight 3,514 +/- 613 g) were analyzed. Three patients needed mechanical support (2 died), 19 had delayed sternal closure, 17 had arrhythmias, and 9 had ST changes. The most common coronary artery pulse Doppler flow pattern consisted of a late systolic peak followed by low-velocity flow throughout diastole. A left main coronary artery (LMCA) velocity time integral >0.14 (P = .01) and an LMCA peak systolic velocity >0.6 cm/s (P = .05) were associated with need for surgical revision.

CONCLUSION

Abnormalities in LMCA flow were associated with the need for surgical revision in patients with TGA undergoing the arterial switch operation. Normal coronary artery pulse Doppler flow patterns after the arterial switch operation consisted of a late systolic peak followed by low-velocity flow throughout diastole.

Prevalence of hepatopulmonary syndrome in children

OBJECTIVE

The hepatopulmonary syndrome is defined as a triad of liver disease, hypoxemia, and intrapulmonary vascular dilation. The reported prevalence of hepatopulmonary syndrome in adults with cirrhosis ranges from 4% to 29%; however, the prevalence of hepatopulmonary syndrome and its outcome in children is unknown. The objective of this study was to describe prospectively the prevalence of intrapulmonary vascular dilation and hepatopulmonary syndrome in children with liver disease.

METHODS

Pulse oximetry was undertaken in children with liver disease, and those with oxygen saturation < or = 97%, those with cirrhosis, and those with clinically severe portal hypertension from other causes underwent contrast-enhanced echocardiography for detection of intrapulmonary vascular dilations. Patients with intrapulmonary vascular dilation underwent arterial blood gas analysis and technetium-99m-labeled macroaggregated albumin scan.

RESULTS

Oxygen saturation was measured in 301 children and was < or = 97% in 8. These 8 and an additional 18 patients with cirrhosis or portal hypertension underwent contrast-enhanced echocardiography. Seven (27%) patients had intrapulmonary vascular dilation detected by contrast-enhanced echocardiography; 2 of these patients had abnormal arterial blood gas analysis and thus met diagnostic criteria for hepatopulmonary syndrome (representing 8% of patients with cirrhosis or severe portal hypertension). Both patients with hepatopulmonary syndrome had abnormal pulse oximetry. Technetium-99m-labeled macroaggregated albumin scans for 6 patients showed a median 6.5% (range: 4%-12%) tracer uptake outside the lungs.

CONCLUSIONS

Hepatopulmonary syndrome occurs in an important minority of children with cirrhosis or severe portal hypertension. Additional studies should be undertaken to determine the importance of intrapulmonary vascular dilation without hepatopulmonary syndrome and the impact of hepatopulmonary syndrome on the outcomes of affected children.

Morphological and functional evaluation of murine heterotopic cardiac grafts using ultrasound biomicroscopy

This study investigated the use of an ultrasound biomicroscope (UBM) to observe murine heterotopic cardiac transplants. By using an UBM (30 MHz), cardiac isografts in eight mice were studied on days 1, 5, 14 and 50 posttransplantation. The same method was tested in allografts in two mice on days 1, 5, 7 and 9. Two-dimensional imaging delineated the graft structures with high spatial resolution. In isografts, M-mode recording showed gradually decreased left ventricular (LV) wall thickness and chamber dimension, but increased LV fractional shortening. Doppler sampling measured blood velocities from the ascending aorta, left coronary artery (LCA), aortic and mitral orifices of grafts. In isografts, LCA forward flow caused by native circulation to perfuse the graft myocardium increased from day 1 to 5, then moderately decreased by day 14 and stabilized thereafter. In allografts, LCA forward flow sharply decreased to almost zero between day 5-9. Therefore, UBM is a reliable method for following the survival status of cardiac grafts in mice.

Outcome after prenatal diagnosis of tricuspid atresia: a multicenter experience

BACKGROUND

The outcome of prenatally diagnosed tricuspid atresia (TA) is undefined. We sought to characterize clinical and echocardiographic features of fetal TA and to determine factors associated with mortality.

METHODS AND RESULTS

All fetuses with TA (n = 88) seen at 3 tertiary care institutions from 1990 to 2005 were reviewed. There were 58 liveborn infants (median gestational age 38 weeks, range 24-40 weeks), 4 in utero demises, 25 terminations of pregnancy, and 1 mother lost to follow-up. Obstruction was present at the pulmonary valve in 27 (45%), aortic valve in 6 (10%), and aortic arch in 15 (25%). Three neonates received compassionate care, 1 died with multiple extracardiac anomalies, 2 were lost to follow-up, and 52 liveborns were actively managed with Blalock-Taussig shunt (23), Norwood palliation (14), pulmonary artery band (10), bidirectional cavopulmonary connection (3), atrial septostomy (1), and right outflow stent (1). Of those actively managed, there were 7 (14%) of 52 who died. Kaplan-Meier estimates of survival were 91% at 1 month, 87% at 6 months, and 83% at 1 year with no subsequent deaths for 13 years. By multivariate analysis, 2 independent factors were associated with an increase in time-related mortality in the actively managed group: presence of chromosomal anomaly or syndrome (P = .005) and use of extracorporeal membrane oxygenation (P = .002).

CONCLUSIONS

This is the largest study describing TA in fetus. Compared with published observations of TA diagnosed postnatally, antenatal diagnosis of TA appears to have similar short-term survival in pregnancies surviving to birth.

Etiology and outcome of prenatally detected paracardial cystic lesions: a case series and review of the literature

OBJECTIVES

Isolated paracardial cysts, defined as cystic structures adjacent to or originating from the heart, are rare and etiologically heterogeneous congenital abnormalities. The purpose of this study was to review our experience with prenatally diagnosed isolated cysts.

METHODS

We reviewed retrospectively the medical charts and ultrasound records of all cases with an antenatal diagnosis of paracardial cyst at our institution between 2001 and 2006. Where applicable, the diagnosis was further substantiated by other imaging modalities and pathology.

RESULTS

The cysts in six fetuses were diagnosed at a median gestation of 20 (range, 19-38) weeks. Three of these fetuses presented with a fluid-filled cyst attached to or within the pericardial space (pericardial cysts), which resolved spontaneously by the time of delivery. In contrast, the cysts did not change in size or shape in the remaining three fetuses. Postnatal examination of the persistent cysts revealed three different etiologies: (1) a microcystic lymphangioma, located in the anterior mediastinum; (2) an isolated neurenteric cyst; and (3) a single bronchogenic cyst, both within the posterior mediastinum. The lymphangioma and neurenteric cyst were removed surgically after birth.

CONCLUSIONS

Fetal echocardiography enables early detection of paracardial cyst. Pericardial cysts disappeared spontaneously during the course of gestation without signs of fetal cardiac compromise, suggesting a benign prognosis. Imaging by magnetic resonance and computerized tomography were particularly useful to clarify the etiology, structure and extent of those cysts that had not resolved by the time of birth. Published by John Wiley & Sons, Ltd.

Extent of myocardial non-compaction: comparison between MRI and echocardiographic evaluation

BACKGROUND

Non-compaction of the left ventricular myocardium is an important cause of cardiomyopathy. There is no clear consensus about its diagnostic criteria or the diagnostic test of choice. MRI is increasingly used in the pediatric cardiac field because of its superior and objective image quality.

OBJECTIVE

To compare the echocardiographic and MRI findings in four patients with recently diagnosed ventricular non-compaction.

MATERIALS AND METHODS

We compared the extent of myocardial involvement shown at MRI and echocardiography in four individuals, two patients with echocardiographic diagnosis of left ventricular non-compaction, and two family members of one of the patients.

RESULTS

In all patients, MRI showed wider area of involvement than echocardiography. A definite diagnosis was entertained in only two patients by echocardiography but in all by MRI. Cine imaging was diagnostic of the disease in all patients. Black-blood pool imaging with double-inversion recovery sequence also helped to visualize the abnormal areas by showing slow flow artifacts in the four- and two-chamber images.

CONCLUSION

MRI provided better delineation of the extent of the abnormal trabeculation in patients with non-compaction of the left ventricular myocardium. It was particularly useful when the myocardial involvement was subtle, as in the asymptomatic family members.

Clinical Features, Management, and Outcome of Children With Fetal and Postnatal Diagnoses of Isomerism Syndromes

Background— Isomerism is associated with a complex spectrum of anomalies. There is paucity of data on prenatally detected cases.

Methods and Results— Between January 1990 and February 2004, 83 of 166 cases (50%) had a prenatal diagnosis of left isomerism (LAI; 52 of 97) or right isomerism (RAI; 31 of 69) at our institution. The spectrum of anomalies, management, and outcomes was compared for fetal and postnatal diagnoses of LAI and RAI. RAI more often than LAI was associated with AV septal defect (90% versus 56%; P <0.0001), pulmonary outflow obstruction (91% versus 37%; P <0.0001), total anomalous pulmonary venous drainage (73% versus 13%; P <0.0001), and abnormal VA connections (68% versus 33%; P <0.0001), whereas inferior vena cava interruption (3% versus 93%; P <0.0001), complete AV block (0% versus 13%; P =0.004), aortic obstruction (6% versus 33%; P <0.0001), and extracardiac defects (5% versus 25%; P =0.006) were less common. The spectrum of lesions was comparable for fetal and postnatal cases, except for AV block (fetal, 25%; postnatal, 0%; P =0.0002) and AV septal defect (fetal, 67%; postnatal, 42%; P =0.023) in LAI. Fetal demise was due mainly to pregnancy termination (LAI, 42%; RAI, 45%). Survival of actively managed children with LAI was significantly better than for those with RAI ( P <0.0001) but did not differ with regard to fetal versus postnatal diagnosis. Most LAI cases required no intervention or underwent successful biventricular cardiac surgery (65%), unlike RAI cases (13%; P <0.0001).

Conclusions— Prenatal diagnosis did not affect overall survival despite facilitated care. The prognosis of RAI was worse compared with LAI because of more complex associated cardiac defects and the inability to perform successful surgical procedures.

Determinants of outcome in isolated ventricular noncompaction in childhood

Isolated ventricular noncompaction is now recognized as an important cause of pediatric cardiomyopathy; however, predictors of outcome have yet to be detailed. Echocardiographic features at presentation, including increased noncompacted to compacted segment ratio and enlarged left ventricular dimension, were found to be associated with poor outcomes (heart transplantation, transplant listing, or death).