Consensus-Based Development of a Pediatric Echocardiography Complexity Score: Design, Rationale, and Results of a Quality Improvement Collaborative.

BACKGROUND: The complexity of congenital heart disease has been primarily stratified on the basis of surgical technical difficulty, specific diagnoses, and associated outcomes. We report on the refinement and validation of a pediatric echocardiography complexity (PEC) score. METHODS AND RESULTS: The American College of Cardiology Quality Network assembled a panel from 12 centers to refine a previously published PEC score developed in a single institution. The panel refined complexity categories and included study modifiers to account for complexity related to performance of the echocardiogram. Each center submitted data using the PEC scoring tool on 15 consecutive inpatient and outpatient echocardiograms. Univariate and multivariate analyses were performed to assess for independent predictors of longer study duration. Among the 174 echocardiograms analyzed, 68.9% had underlying congenital heart disease; 44.8% were outpatient; 34.5% were performed in an intensive care setting; 61.5% were follow-up; 46.6% were initial or preoperative; and 9.8% were sedated. All studies had an assigned PEC score. In univariate analysis, longer study duration was associated with several patient and study variables (age <2 years, PEC 4 or 5, initial study, preoperative study, junior or trainee scanner, and need for additional imaging). In multivariable analysis, a higher PEC score of 4 or 5 was independently associated with longer study duration after controlling for study variables and center variation. CONCLUSIONS: The PEC scoring tool is feasible and applicable in a variety of clinical settings and can be used for correlation with diagnostic errors, allocation of resources, and assessment of physician and sonographer effort in performing, interpreting, and training in pediatric echocardiography.

Tricuspid Atresia with Absent Pulmonary Valve with Nearly Discontinuous Branch Pulmonary Arteries.

Absent pulmonary valve with tricuspid atresia or tricuspid stenosis (APV-TA/TS) is an extremely rare congenital heart defect associated with significant morbidity and mortality. Compared to Tetralogy of Fallot with Absent Pulmonary Valve Syndrome, branch pulmonary arteries are not typically significantly dilated. We present the case of a newborn male prenatally diagnosed APV-TA with intact ventricular septum (IVS) and nearly discontinuous branch pulmonary arteries, the surgical strategy employed, and the salient hemodynamic factors considered in the medical decision-making.

A Pilot Study Characterizing Flow Patterns in the Thoracic Aorta of Patients With Connective Tissue Disease: Comparison to Age- and Gender-Matched Controls via Fluid Structure Interaction.

Prior computational and imaging studies described changes in flow patterns for patients with Marfan syndrome, but studies are lacking for related populations. This pilot study addresses this void by characterizing wall shear stress (WSS) indices for patients with Loeys-Dietz and undifferentiated connective tissue diseases. Using aortic valve-based velocity profiles from magnetic resonance imaging as input to patient-specific fluid structure interaction (FSI) models, we determined local flow patterns throughout the aorta for four patients with various connective tissue diseases (Loeys-Dietz with the native aorta, connective tissue disease of unclear etiology with native aorta in female and male patients, and an untreated patient with Marfan syndrome, as well as twin patients with Marfan syndrome who underwent valve-sparing root replacement). FSI simulations used physiological boundary conditions and material properties to replicate available measurements. Time-averaged WSS (TAWSS) and oscillatory shear index (OSI) results are presented with localized comparison to age- and gender-matched control participants. Ascending aortic dimensions were greater in almost all patients with connective tissue diseases relative to their respective control. Differences in TAWSS and OSI were driven by local morphological differences and cardiac output. For example, the model for one twin had a more pronounced proximal descending aorta in the vicinity of the ductus ligamentum that impacted WSS indices relative to the other. We are optimistic that the results of this study can serve as a foundation for larger future studies on the connective tissue disorders presented in this article.

Applicability and Durability of Valve-Sparing Tetralogy of Fallot Repair.

BACKGROUND: Although valve-sparing repair remains ideal for patients with tetralogy of Fallot, the durability of valve-sparing repair and which patients may have been better served with a transannular patch remain unclear. METHODS: Retrospective review was performed of tetralogy of Fallot operations at our institution from January 2008 to December 2018. Standard demographic data were collected, including echocardiographic parameters, operative details, and clinical outcomes. Statistical analysis was performed comparing the transannular patch and valve-sparing repair groups. RESULTS: Sixty-seven patients underwent tetralogy of Fallot repair with a median age of 4.5 (3.2-6.0) months and weight of 5.8 (5.2, 6.7) kg. Seventeen (25%) patients underwent transannular patch repair and 50 (75%) patients underwent valve-sparing repair. There was no difference in age or weight between patients who underwent a transannular patch repair and those who underwent a valve-sparing repair. At last follow-up (median 42 months), there was a trend of a higher peak pulmonary valve/right ventricular outflow tract gradient (P = .06) in the valve-sparing group, but no difference in the pulmonary valve annulus z-scores. Additionally, the pulmonary valve z-scores in the valve-sparing group decreased from -2.3 ± 1.0 on predischarge echocardiogram of to -1.2 ± 1.6 on last follow-up, with the peak gradient on predischarge 23 (0-37) mm Hg remaining stable on last follow-up at 18 (0-29) mm Hg. There was one reoperation: pulmonary valve replacement six years after a transannular patch. CONCLUSIONS: Obtaining a postrepair pulmonary valve z-score of -2 yields satisfactory, stable valve-sparing repair with pulmonary valve growth, acceptable gradients, minimal regurgitation, and high freedom from reintervention during follow-up.

Height Versus Body Surface Area to Normalize Cardiovascular Measurements in Children Using the Pediatric Heart Network Echocardiographic Z-Score Database.

Normalizing cardiovascular measurements for body size allows for comparison among children of different ages and for distinguishing pathologic changes from normal physiologic growth. Because of growing interest to use height for normalization, the aim of this study was to develop height-based normalization models and compare them to body surface area (BSA)-based normalization for aortic and left ventricular (LV) measurements. The study population consisted of healthy, non-obese children between 2 and 18 years of age enrolled in the Pediatric Heart Network Echo Z-Score Project. The echocardiographic study parameters included proximal aortic diameters at 3 locations, LV end-diastolic volume, and LV mass. Using the statistical methodology described in the original project, Z-scores based on height and BSA were determined for the study parameters and tested for any clinically significant relationships with age, sex, race, ethnicity, and body mass index (BMI). Normalization models based on height versus BSA were compared among underweight, normal weight, and overweight (but not obese) children in the study population. Z-scores based on height and BSA were calculated for the 5 study parameters and revealed no clinically significant relationships with age, sex, race, and ethnicity. Normalization based on height resulted in lower Z-scores in the underweight group compared to the overweight group, whereas normalization based on BSA resulted in higher Z-scores in the underweight group compared to the overweight group. In other words, increasing BMI had an opposite effect on height-based Z-scores compared to BSA-based Z-scores. Allometric normalization based on height and BSA for aortic and LV sizes is feasible. However, height-based normalization results in higher cardiovascular Z-scores in heavier children, and BSA-based normalization results in higher cardiovascular Z-scores in lighter children. Further studies are needed to assess the performance of these approaches in obese children with or without cardiac disease.

Practice Variations in Pediatric Echocardiography Laboratories.

Quantification guidelines for pediatric echocardiograms were published in 2010 establishing consensus regarding standard measurements. However, a standard protocol for performance and analysis of pediatric echocardiograms was not defined. This study aims to identify practice variations among pediatric laboratories. A survey was sent to 85 North American pediatric laboratory directors. The survey included 29 questions assessing: demographics, methods of image acquisition, parameters routinely evaluated and reported, and methods used to assess chamber sizes, valves, and ventricular function. There were 47/85 (55%) responses; 83% were academic centers and 77% in an urban setting. Wide variations exist in acquisition method (clips versus sweeps) and color scale settings. The most commonly used methods for left ventricular (LV) function are M-mode shortening fraction, qualitative assessment, and Doppler Tissue Imaging. The most commonly used parameter for right ventricular function is qualitative. LV mass is routinely measured by the majority of centers with variations in methods of calculation. Conversely, while a minority measure left atrial volume, there is consensus regarding the preferred method. While multiple techniques exist for assessing valves, qualitative assessment is reported to be the preferred method. Despite quantification guidelines, there is a lack of uniformity in performance and analysis of pediatric echocardiograms. Further studies are needed to determine why variations exist and whether development of consensus guidelines might improve interpretation, consistency and quality of reports, patient care, and provide a standardized system allowing for comparative research among centers.

The Effect of Image Review before Patient Discharge on Study Completeness and Sonographer Job Satisfaction in a Pediatric Echocardiographic Laboratory.

BACKGROUND: Incomplete echocardiographic assessment accounts for approximately 10% of preventable diagnostic errors and may place children at risk for adverse outcomes or increased testing. The aim of this study was to determine if physician review of images improves study completeness. METHODS: A prospective quality improvement (QI) study initiated physician review of first-time echocardiographic studies for completeness before patient discharge. Studies were incomplete if not all anatomic structures were diagnostically demonstrated. QI examinations were compared with controls obtained before study initiation. Demographic and clinical information and duration of scan were collected during the control and QI periods. An anonymous survey was administered to the sonographers to assess perceptions of the intervention. RESULTS: There were no differences between the QI (n = 63) and control (n = 63) groups in age, height, weight, and technical barriers. After study completion, 35% of control scans versus 5% of QI scans were incomplete (P < .001). In the QI group, the sonographer, physician, or both returned to scan in 12 (19%), nine (14%), and two (3%) studies, respectively. QI studies were longer than control studies (44 vs 36 min, P = .003) before review. Physician review added a median of 6 min (range, 1-28 min). The majority of sonographers believed that immediate review improved communication, and 50% believed that it improved their job satisfaction. CONCLUSIONS: Review of initial outpatient echocardiographic examinations before patient discharge significantly improves study completeness. Review adds a nominal amount of time to total study duration, improves sonographer-physician communication, and may prevent unnecessary testing, potentially reducing the cost of care.

Abnormal mitral valve anatomy in d-transposition of the great arteries: anatomic characterization and surgical outcomes.

Mitral valve anomalies can occur with S,D,D-transposition of the great arteries (d-TGA). Their influence on surgical technique and outcome after an arterial switch operation (ASO) has not been well described. Patients with d-TGA who underwent ASO from February 1990 to January 2011 were identified. Echocardiograms, operative reports, hospital course, and latest follow-up evaluation were reviewed. A total of 218 infants underwent ASO at a median age of 15.8 days. Survival was 95 % during a mean follow-up period of 60 months. Nine patients (4 %) were found to have similar mitral valve anomalies including anterior malalignment conoventricular septal defect, anterior displacement of the mitral valve toward the left ventricular outflow tract (LVOT), malpositioning of the posteromedial papillary muscle, unusual rotation of the mitral valve leaflets orienting the commissure toward the anterior ventricular septum, and redundant mitral valve tissue extending into the LVOT. Coarctation was more frequent in this subgroup (33 vs. 10 %; p = 0.05). Preoperative echocardiography consistently indicated suspicion of a cleft mitral valve with chordal attachments to the ventricular septum causing potential LVOT obstruction. Operative inspection did not identify a cleft or anomalous attachments in any patient, and no valvuloplasty or chordal manipulation was performed. The average hospital length of stay were similar (30.7 vs. 25.3 days; p = 0.54). One patient died late due to progressive LVOT obstruction, and one required heart transplantation. No patient had significant mitral valve regurgitation. We conclude that mitral valve anomalies associated with d-TGA are rare but present with consistent anatomic features and higher risk of coarctation. Unusual mitral valve apparatus positioning and chordal redundancy can suggest the need for valvuloplasty and chordal resection preoperatively, but this is rarely needed.