Sustained radiation reduction following initial quality improvement intervention in a paediatric cardiac catheterisation laboratory.

BACKGROUND: As part of a quality improvement project beginning in October 2011, our centre introduced changes to reduce radiation exposure during paediatric cardiac catheterisations. This led to significant initial decreases in radiation to patients. Starting in April 2016, we sought to determine whether these initial reductions were sustained. METHODS: After a 30-day trial period, we implemented (1) weight-based reductions in preset frame rates for fluoroscopy and angiography, (2) increased use of collimators and safety shields, (3) utilisation of stored fluoroscopy and virtual magnification, and (4) hiring of a devoted radiation technician. We collected patient weight (kg), total fluoroscopy time (min), and procedure radiation dosage (cGy-cm2) for cardiac catheterisations between October, 2011 and September, 2019. RESULTS: A total of 1889 procedures were evaluated (196 pre-intervention, 303 in the post-intervention time period, and 1400 in the long-term group). Fluoroscopy times (18.3 ± 13.6 pre; 19.8 ± 14.1 post; 17.11 ± 15.06 long-term, p = 0.782) were not significantly different between the three groups. Patient mean radiation dose per kilogram decreased significantly after the initial quality improvement intervention (39.7% reduction, p = 0.039) and was sustained over the long term (p = 0.043). Provider radiation exposure was also significantly decreased from the onset of this project through the long-term period (overall decrease of 73%, p < 0.01) despite several changes in the interventional cardiologists who made up the team over this time period. CONCLUSION: Introduction of technical and clinical practice changes can result in a significant reduction in radiation exposure for patients and providers in a paediatric cardiac catheterisation laboratory. These reductions can be maintained over the long term.

scaRNA1 Levels Alter Pseudouridylation in Spliceosomal RNA U2 Affecting Alternative mRNA Splicing and Embryonic Development.

The heart is the first major organ to develop during embryogenesis and must receive proper spatiotemporal signaling for proper development. Failure of proper signaling between the first and second heart fields at twenty days gestation contributes to the generation of a congenital heart defect. The most common cyanotic congenital heart defect is tetralogy of Fallot (TOF) which requires surgical intervention in the first year of life. In right ventricular tissue of infants born with TOF, the levels of scaRNA1 are reduced and mRNA splicing is dysregulated. In this study, we investigate a method of quantifying pseudouridylation levels in relation to scaRNA1 levels in spliceosomal RNA U2 in three different groups of samples: right ventricular (RV) tissue of infants born with TOF versus RV tissue from normally developing infants, scaRNA1 knockdown in primary normal cardiomyocytes derived from normally developing infants, and scaRNA1 overexpression in primary cells derived from RV tissue from infants born with TOF. We hypothesize that the amount of pseudouridylation is dependent on scaRNA1 level, compromising spliceosomal function and therefore, contributing to the generation of a congenital heart defect. Our results revealed a statistically significant decrease of pseudouridylation levels in the right ventricular tissue of infants born with TOF compared to the controls. Knocking down the scaRNA1 levels in normal primary cardiomyocytes resulted in a statistically significant decrease of pseudouridylation. Finally, an overexpression of scaRNA1 in TOF primary cells resulted in an increase in pseudouridylation levels, but it did not achieve statistical significance. Our previous research provided an association between scaRNA levels, alternative splicing, and development. Here, we demonstrate that pseudouridylation levels in spliceosomal RNA U2 is dependent on the expression level of scaRNA1. Although further investigation is needed, we believe that scaRNA expression regulates biochemical modifications to spliceosomal RNAs, adjusting the fidelity of the spliceosome, allowing for controlled alternative splicing of mRNA that is important in embryonic development. If validated, this is an underappreciated mechanism that is critical for regulating proper embryonic development.

Exercise restriction is not associated with increasing body mass index over time in patients with anomalous aortic origin of the coronary arteries.

Anomalous aortic origin of the coronary arteries is associated with exercise-induced ischaemia, leading some physicians to restrict exercise in patients with this condition. We sought to determine whether exercise restriction was associated with increasing body mass index over time. From 1998 to 2015, 440 patients ⩽30 years old were enrolled into an inception cohort. Exercise-restriction status was documented in 143 patients. Using linear mixed model repeated-measures regression, factors associated with increasing body mass index z-score over time, including exercise restriction and surgical intervention as time-varying covariates, were investigated. The 143 patients attended 558 clinic visits for which exercise-restriction status was recorded. The mean number of clinic visits per patient was 4, and the median duration of follow-up was 1.7 years (interquartile range (IQR) 0.5-4.4). The median age at first clinic visit was 10.3 years (IQR 7.1-13.9), and 71% (101/143) were males. All patients were alive at their most recent follow-up. At the first clinic visit, 54% (78/143) were exercise restricted, and restriction status changed in 34% (48/143) during follow-up. The median baseline body mass index z-score was 0.2 (IQR 0.3-0.9). In repeated-measures analysis, neither time-related exercise restriction nor its interaction with time was associated with increasing body mass index z-score. Surgical intervention and its interaction with time were associated with decreasing body mass index z-score. Although exercise restriction was not associated with increasing body mass index over time, surgical intervention was associated with decreasing body mass index z-score over time in patients with anomalous aortic origin of the coronary arteries.

scaRNAs regulate splicing and vertebrate heart development.

Alternative splicing (AS) plays an important role in regulating mammalian heart development, but a link between misregulated splicing and congenital heart defects (CHDs) has not been shown. We reported that more than 50% of genes associated with heart development were alternatively spliced in the right ventricle (RV) of infants with tetralogy of Fallot (TOF). Moreover, there was a significant decrease in the level of 12 small cajal body-specific RNAs (scaRNAs) that direct the biochemical modification of specific nucleotides in spliceosomal RNAs. We sought to determine if scaRNA levels influence patterns of AS and heart development. We used primary cells derived from the RV of infants with TOF to show a direct link between scaRNA levels and splice isoforms of several genes that regulate heart development (e.g., GATA4, NOTCH2, DAAM1, DICER1, MBNL1 and MBNL2). In addition, we used antisense morpholinos to knock down the expression of two scaRNAs (scarna1 and snord94) in zebrafish and saw a corresponding disruption of heart development with an accompanying alteration in splice isoforms of cardiac regulatory genes. Based on these combined results, we hypothesize that scaRNA modification of spliceosomal RNAs assists in fine tuning the spliceosome for dynamic selection of mRNA splice isoforms. Our results are consistent with disruption of splicing patterns during early embryonic development leading to insufficient communication between the first and second heart fields, resulting in conotruncal misalignment and TOF. Our findings represent a new paradigm for determining the mechanisms underlying congenital cardiac malformations.

del Nido versus St. Thomas Cardioplegia Solutions: A Single-Center Retrospective Analysis of Post Cross-Clamp Defibrillation Rates.

There are many cardioplegia solutions currently in use for pediatric cardiopulmonary bypass (CPB). The most common being del Nido solution. Another common cardioplegia solution used for pediatric CPB is St. Thomas. In October 2014, Children's Mercy Kansas City changed from the use of modified St. Thomas to del Nido. This study compared rates of post cross-clamp fibrillation requiring defibrillation between del Nido solution and modified St. Thomas solution stratified by weight at Children's Mercy Kansas City. This retrospective study consisted of 394 patients who underwent cardiac surgery requiring cardioplegia between January 1, 2014 and July 31, 2015. The outcome measured was defibrillation upon cross-clamp removal. Statistical significance was determined using Fishers exact test with a two-sided significance level of .05. Incidence of defibrillation post cross-clamp removal was 4.4% in the del Nido group and 26.8% in the St. Thomas group (p < .0001). Analysis by weight stratifications displays a reduction in post cross-clamp defibrillation rates in groups using the del Nido solution. The 0- to 6-kg category had an incidence of fibrillation of 1.23% in the del Nido group and 17.5% in the St. Thomas group (p < .0003). The 6- to 15-kg category had an incidence of defibrillation of 1.82% in the del Nido group and 14% in the St. Thomas group (p < .0198). The 15- to 60-kg category had an incidence of defibrillation of 8.9% in the del Nido group and 61% in the St. Thomas group (p < .0001). The >60-kg category had an incidence of defibrillation of 16.7% in the del Nido group and 63% in the St. Thomas group (p < .0623). This study demonstrates a 6-fold decrease in the overall rate of defibrillation post cross-clamp removal between St. Thomas and del Nido cardioplegia solutions. Analyses of weight stratifications demonstrate a decrease in the rate of defibrillation post cross-clamp removal in all categories within the del Nido group.

A tissue-specific gene expression template portrays heart development and pathology.

Congenital heart defects (CHD) are the most common cause of death in children under the age of 1. Tetralogy of Fallot (TOF) is a severe CHD that results from developmental defects in the conotruncal outflow tract. Recently, a tissue-specific gene expression template (GET) was derived from microarray data that accurately characterized multiple normal human tissues. We used the GET to examine spatial, temporal, and a pathological condition (TOF) within a single organ, the heart. The GET, as previously defined, generally identified temporal and spatial differences in the cardiac tissue. Differences in the stoichiometry of the GET reflected the severe developmental disturbance associated with TOF. Our analysis suggests that the homoeostatic equilibrium assessed by the GET at the inter-organ level is generally maintained at the intra-organ level as well.

The Society of Thoracic Surgeons Congenital Heart Surgery Database: 2023 Update on Outcomes and Research.

The Society of Thoracic Surgeons (STS) Congenital Heart Surgery Database (CHSD) continues to be the most comprehensive database of congenital and pediatric cardiothoracic surgical procedures in the world and contains information on 664,210 operations as of June 30, 2023. The 35th harvest of the STS CHSD data was undertaken in Spring 2023, spanning the 4-year period January 1, 2019, through December 31, 2022, and included 144,919 operations performed at 114 participating sites in North America. The harvest analysis was successfully executed by the STS Research and Analytic Center. The overall unadjusted mortality rate was 2.68% and has remained stable over the 4 years included in the current harvest window. Mortality is highest in neonates (7.4%) and lowest in children (1.1%). As in prior analyses, observed mortality and postoperative length of stay in the database increase with an increase in STS-European Association for Cardio-Thoracic Surgery (STAT) Congenital Heart Surgery Mortality Categories. This quality report summarizes contemporary outcomes, provides the odds ratios for the CHSD risk model variables based on this analysis, and describes on-going efforts to improve data collection and augment analytical approaches. Lastly, 5 research publications completed in the last year using data from the CHSD are also summarized.

Transesophageal Echocardiography in Healthy Young Adult Male Baboons (Papio hamadryas anubis): Normal Cardiac Anatomy and Function in Subhuman Primates Compared to Humans.

Implantable, viable tissue engineered cardiovascular constructs are rapidly approaching clinical translation. Species typically utilized as preclinical large animal models are food stock ungulates for which cross species biological and genomic differences with humans are great. Multiple authorities have recommended developing subhuman primate models for testing regenerative surgical strategies to mitigate xenotransplant inflammation. However, there is a lack of specific quantitative cardiac imaging comparisons between humans and the genomically similar baboons (Papio hamadryas anubis). This study was undertaken to translate to baboons transesophageal echocardiographic functional and dimensional criteria defined as necessary for defining cardiac anatomy and function in the perioperative setting. Seventeen young, healthy baboons (approximately 30 kg, similar to 5 year old children) were studied to determine whether the requisite 11 views and 52 measurement parameters could be reliably acquired by transesophageal echocardiography (TEE). The obtained measurements were compared to human adult normative literature values and to a large relational database of pediatric "normal heart" echo measurements. Comparisons to humans, when normalized to BSA, revealed a trend in baboons toward larger mitral and aortic valve effective orifice areas and much larger left ventricular muscle mass and wall thickness, but similar pulmonary and tricuspid valves. By modifying probe positioning relative to human techniques, all recommended TEE views except transgastric could be replicated. To supplement, two transthoracic apical views were discovered that in baboons could reliably replace the transgastric TEE view. Thus, all requisite echo views could be obtained for a complete cardiac evaluation in Papio hamadryas anubis to noninvasively quantify cardiac structural anatomy, physiology, and dimensions. Despite similarities between the species, there are subtle and important physiologic and anatomic differences when compared to human.

The Society of Thoracic Surgeons Congenital Heart Surgery Database: 2022 Update on Outcomes and Research.

The Society of Thoracic Surgeons (STS) Congenital Heart Surgery Database continues to be one of the most comprehensive clinical outcomes registries capturing almost all pediatric cardiothoracic surgical operations undertaken in the United States. The latest analysis of aggregate outcomes was performed after the 33rd data harvest and included congenital and pediatric cardiac operations performed between July 1, 2017 and June 30, 2021. This article summarizes these contemporary outcomes and provides a context for the interpretation of these outcomes. In addition this article describes ongoing efforts to improve data collection and augment analytical approaches. Finally, research activities undertaken in the last year using data from the database are also summarized.

Hybrid palliation versus nonhybrid management for a multi-institutional cohort of infants with critical left heart obstruction.

OBJECTIVE: To compare patient characteristics and overall survival for infants with critical left heart obstruction after hybrid palliation (bilateral pulmonary artery banding with or without ductal stenting) versus nonhybrid management (eg, Norwood, primary transplantation, biventricular repair, or transcatheter/surgical aortic valvotomy). METHODS: From 2005 to 2019, 1045 infants in the Congenital Heart Surgeons' Society critical left heart obstruction cohort underwent interventions across 28 institutions. Using a balancing score propensity analysis, 214 infants who underwent hybrid palliation and 831 infants who underwent nonhybrid management were proportionately matched regarding variables significantly associated with mortality and variables noted to significantly differ between groups. Overall survival between the 2 groups was adjusted by applying balancing scores to nonparametric estimates. RESULTS: Compared with the nonhybrid management group, infants who underwent hybrid palliation had lower birth weight, smaller gestational age, and higher prevalence of in-utero interventions, noncardiac comorbidities, preoperative mechanical ventilation, absent interatrial communication, and moderate or severe mitral valve stenosis (all P values < .03). Unadjusted 12-year survival after hybrid palliation and nonhybrid management, was 55% versus 69%, respectively. After matching, 12-year survival after hybrid palliation versus nonhybrid management was 58% versus 63%, respectively (P = .37). Among matched infants born weighing <2.5 kg, 2-year survival after hybrid palliation versus nonhybrid management was 37% versus 51%, respectively (P = .22). CONCLUSIONS: Infants born with critical left heart obstruction who undergo hybrid palliation have more high-risk characteristics and anatomy versus infants who undergo nonhybrid management. Nonetheless, after adjustment, there was no significant difference in 12-year survival after hybrid palliation versus nonhybrid management. Mortality remains high, and hybrid palliation confers no survival advantage, even for lower-birth-weight infants.

The World Society for Pediatric and Congenital Heart Surgery: 2021 Update of the World Database for Pediatric and Congenital Heart Surgery.

BACKGROUND: The World Database for Pediatric and Congenital Heart Surgery (WDPCHS), sponsored by the World Society for Pediatric and Congenital Heart Surgery (WSPCHS), provides complex programmatic outcomes analyses for all members of the WSPCHS. METHODS: The Data center, currently at Kirklin Institute for Research in Surgical Outcomes (KIRSO), University of Alabama, Birmingham (USA), provides biannual reports to all active members of the database. This report presents a descriptive analysis of these procedures submitted from January 1, 2017 to December 31, 2020. RESULTS: A total of 37,386 procedures were submitted with an overall mortality of 4.3%. The majority of submissions were from Asian countries. The majority of cases submitted from these countries were of Society of Thoracic Surgeons (STS)-European Association for Cardio-Thoracic Surgery (STAT) Mortality Categories I and II. CONCLUSIONS: The WSPCHS accomplished one of its missions in 2017 when the WDPCHS began accepting data from pediatric and congenital heart surgery programs across the globe. In doing so, it became one of the first organizations to create a platform for the exchange of knowledge and experience, regardless of the socioeconomic status of the particular program or country.

Identifying genetic factors that contribute to the increased risk of congenital heart defects in infants with Down syndrome.

Atrioventricular septal defects (AVSD) are a severe congenital heart defect present in individuals with Down syndrome (DS) at a > 2000-fold increased prevalence compared to the general population. This study aimed to identify risk-associated genes and pathways and to examine a potential polygenic contribution to AVSD in DS. We analyzed a total cohort of 702 individuals with DS with or without AVSD, with genomic data from whole exome sequencing, whole genome sequencing, and/or array-based imputation. We utilized sequence kernel association testing and polygenic risk score (PRS) methods to examine rare and common variants. Our findings suggest that the Notch pathway, particularly NOTCH4, as well as genes involved in the ciliome including CEP290 may play a role in AVSD in DS. These pathways have also been implicated in DS-associated AVSD in prior studies. A polygenic component for AVSD in DS has not been examined previously. Using weights based on the largest genome-wide association study of congenital heart defects available (2594 cases and 5159 controls; all general population samples), we found PRS to be associated with AVSD with odds ratios ranging from 1.2 to 1.3 per standard deviation increase in PRS and corresponding liability r2 values of approximately 1%, suggesting at least a small polygenic contribution to DS-associated AVSD. Future studies with larger sample sizes will improve identification and quantification of genetic contributions to AVSD in DS.

Snord94 expression level alters methylation at C62 in snRNA U6.

Understanding the regulation of development can help elucidate the pathogenesis behind many developmental defects found in humans and other vertebrates. Evidence has shown that alternative splicing of messenger RNA (mRNA) plays a role in developmental regulation, but our knowledge of the underlying mechanisms that regulate alternative splicing are incomplete. Notably, a subset of small noncoding RNAs known as scaRNAs (small cajal body associated RNAs) contribute to spliceosome maturation and function through guiding covalent modification of spliceosomal RNAs with either methylation or pseudouridylation on specific nucleotides, but the developmental significance of these modifications is not well understood. Our focus is on one such scaRNA, known as SNORD94 or U94, that guides methylation on one specific cytosine (C62) on spliceosomal RNA U6, thus potentially altering spliceosome function during embryogenesis. We previously showed that in the myocardium of infants with heart defects, mRNA is alternatively spliced as compared to control tissues. We also demonstrated that alternatively spliced genes were concentrated in the pathways that control heart development. Furthermore, we showed that modifying expression of scaRNAs alters mRNA splicing in human cells, and zebrafish embryos. Here we present evidence that SNORD94 levels directly influence levels of methylation at its target region in U6, suggesting a potential mechanism for modifying alternative splicing of mRNA. The potential importance of scaRNAs as a developmentally important regulatory mechanism controlling alternative splicing of mRNA is unappreciated and needs more research.

Ten Years of Data Verification: The Society of Thoracic Surgeons Congenital Heart Surgery Database Audits.

BACKGROUND: The completeness and accuracy of data contained within clinical databases and registries is critical to the reliability of reports emanating from these platforms. Therefore, vigorous data verification processes are a core competency of any mature database or registry. The Society of Thoracic Surgeons Congenital Heart Surgery Database (STS CHSD) has conducted audits of participant data for just over ten years. This report documents the validity of data elements within the STS CHSD. METHODS: We review the various elements of a robust audit process, detail the STS CHSD audit methodology, and report completeness and agreement rates for all adjudicated fields in the most recently completed audit. RESULTS: The rate of completeness for general data elements was 97.6% and the rate of agreement was 97.4%. The rate of completeness for variables in the mortality review was 100% and the rate of agreement was 99.3%. CONCLUSIONS: The STS CHSD audit is a highly structured and reproducible process. The most recently completed audit documents a very high level of completeness and accuracy of data variables, particularly those most germane to outcomes measurement.

Intervention for arch obstruction after the Norwood procedure: Prevalence, associated factors, and practice variability.

OBJECTIVE: Arch obstruction after the Norwood procedure is common and contributes to mortality. We determined the prevalence, associated factors, and practice variability of arch reintervention and assessed whether arch reintervention is associated with mortality. METHODS: From 2005 to 2017, 593 neonates in the Congenital Heart Surgeons' Society Critical Left Heart Obstruction cohort underwent a Norwood procedure. Median follow-up was 3.7 years. Multivariable parametric models, including a modulated renewal analysis, were performed. RESULTS: Of the 593 neonates, 146 (25%) underwent 218 reinterventions for arch obstruction after the Norwood procedure: catheter-based (n = 168) or surgical (n = 50) at a median age of 4.3 months (quartile 1-quartile 3, 2.6-5.7). Interdigitation of the distal aortic anastomosis was protective against arch reintervention. Development of ≥ moderate tricuspid valve regurgitation and right ventricular dysfunction at any point was associated with arch reintervention. Nonsignificant variables for arch reintervention included shunt type and preoperative aortic measurements. Surgical arch reintervention was protective against arch reintervention, but transcatheter reintervention was associated with increased reintervention. Arch reintervention was not associated with increased mortality. There was wide institutional variation in incidence of arch reintervention (range, 0-40 reinterventions per 100 years patient follow-up) and in preintervention gradient (range, 0-64 mm Hg). CONCLUSIONS: Interdigitation of the distal aortic anastomosis during the Norwood procedure decreased the risk of arch reintervention. Surgical arch reintervention is more definitive than transcatheter. Arch reintervention after the Norwood procedure is not associated with increased mortality. Serial surveillance for arch obstruction, integrated with changes in right ventricular function and tricuspid valve regurgitation, is recommended after the Norwood procedure to improve outcomes.

The World Database for Pediatric and Congenital Heart Surgery "A Call to Service for North American Congenital Heart Surgery Programs".

The World Society for Pediatric and Congenital Heart Surgery has endorsed the establishment of an international platform for the exchange of knowledge and experience for those that treat patients with a congenital heart defect. On January 1, 2017, the release of the World Database for Pediatric and Congenital Heart Surgery opened a new era in evaluation of treatment with congenital heart defects. The contribution of data from countries with established congenital surgical databases will greatly enhance the efforts to provide the most accurate measure of overall surgical outcomes across the globe.

The Role of scaRNAs in Adjusting Alternative mRNA Splicing in Heart Development.

Congenital heart disease (CHD) is a leading cause of death in children <1 year of age. Despite intense effort in the last 10 years, most CHDs (~70%) still have an unknown etiology. Conotruncal based defects, such as Tetralogy of Fallot (TOF), a common complex of devastating heart defects, typically requires surgical intervention in the first year of life. We reported that the noncoding transcriptome in myocardial tissue from children with TOF is characterized by significant variation in levels of expression of noncoding RNAs, and more specifically, a significant reduction in 12 small cajal body-associated RNAs (scaRNAs) in the right ventricle. scaRNAs are essential for the biochemical modification and maturation of small nuclear RNAs (spliceosomal RNAs), which in turn are critical components of the spliceosome. This is particularly important because we also documented that splicing of mRNAs that are critical for heart development was dysregulated in the heart tissue of infants with TOF. Furthermore, we went on to show, using the zebrafish model, that altering the expression of these same scaRNAs led to faulty mRNA processing and heart defects in the developing embryo. This review will examine how scaRNAs may influence spliceosome fidelity in exon retention during heart development and thus contribute to regulation of heart development.

Type IV Total Anomalous Pulmonary Venous Connection.

BACKGROUND: Mortality associated with correction of type IV total anomalous pulmonary venous connection (TAPVC) is generally reported in combination with other anatomic types. The objective of this study is to review surgical outcomes associated with the repair of type IV TAPVC by analyzing a multi-institutional cohort specific for this group. We also analyze patient-specific variables that may contribute to poor operative outcomes. METHODS: A retrospective review of the Pediatric Cardiac Care Consortium (PCCC) registry identified patients who underwent repair of type IV TAPVC between 1982 and 2007. Variables reviewed included gender, prematurity, age at repair, anatomic pattern, presence of obstruction, associated anomalies, and operative mortality. Subclassifications were defined as type IV A (2+2 pattern), type IV B (3+1 pattern), and type IV C (bizarre). RESULTS: Of the 2,248 patients with the diagnosis of TAPVC, 215 belonged to type IV. For type IV, the overall unadjusted mortality was 26%. There was no difference in mortality based on the particular anatomic drainage pattern. Twenty-eight percent had partial obstruction of the pulmonary venous return, with no patient having complete obstruction. Patients with obstruction had a significantly greater mortality than those without obstruction (39% vs 20%, P = .005). Approximately 16% of patients who present with obstruction of some pulmonary vein(s) underwent an emergency repair. CONCLUSION: Type IV TAPVC is a rare disease with a diverse anatomic presentation. Even though a small number of the patients with obstruction underwent emergent repair, mortality remained significant. This likely represents the intrinsic lung pathology that must be considered in the postoperative period.

Use of Mechanical Circulatory Support in Isolated Right Heart Failure: A Bridge to Transplantation.

Acute myocarditis may lead to left ventricular dysfunction and subsequent need for cardiac transplantation. We describe a 15-month-old child who presented with right heart failure of unclear cause. Echocardiography showed normal left ventricular function; however, right ventricular function was markedly reduced. The patient required extracorporeal membrane oxygenation followed by placement of a right-sided Berlin EXCOR ventricular assist device. There was little recovery, and the child underwent cardiac transplantation. Subsequent pathologic examination revealed lymphocytic myocarditis. We believe this is the first use of an isolated right ventricular assist device as a bridge to heart transplantation.