Clinical Presentation, Classification, and Outcomes of Cardiogenic Shock in Children.

BACKGROUND: Despite growing cardiogenic shock (CS) research in adults, the epidemiology, clinical features, and outcomes of children with CS are lacking. OBJECTIVES: This study sought to describe the epidemiology, clinical presentation, hospital course, risk factors, and outcomes of CS among children hospitalized for acute decompensated heart failure (ADHF). METHODS: We examined consecutive ADHF hospitalizations (<21 years of age) from a large single-center retrospective cohort. Patients with CS at presentation were analyzed and risk factors for CS and for the primary outcome of in-hospital mortality were identified. A modified Society for Cardiovascular Angiography and Interventions shock classification was created and patients were staged accordingly. RESULTS: A total of 803 hospitalizations for ADHF were identified in 591 unique patients (median age 7.6 years). CS occurred in 207 (26%) hospitalizations. ADHF hospitalizations with CS were characterized by worse systolic function (P = 0.040), higher B-type natriuretic peptide concentration (P = 0.032), and more frequent early severe renal (P = 0.023) and liver (P < 0.001) injury than those without CS. Children presenting in CS received mechanical ventilation (87% vs 26%) and mechanical circulatory support (45% vs 16%) more frequently (both P < 0.001). Analyzing only the most recent ADHF hospitalization, children with CS were at increased risk of in-hospital mortality compared with children without CS (28% vs 11%; OR: 1.91; 95% CI: 1.05-3.45; P = 0.033). Each higher CS stage was associated with greater inpatient mortality (OR: 2.40-8.90; all P < 0.001). CONCLUSIONS: CS occurs in 26% of pediatric hospitalizations for ADHF and is independently associated with hospital mortality. A modified Society for Cardiovascular Angiography and Interventions classification for CS severity showed robust association with increasing mortality.

Atypical infiltrates on endomyocardial biopsy are associated with adverse outcomes in pediatric heart transplantation.

BACKGROUND: The significance of atypical infiltrates (eosinophils or plasma cells) on endomyocardial biopsy (EMB) after pediatric heart transplant (HTx) is not known. We hypothesized that atypical infiltrates are associated with worse post-HTx outcomes. METHODS: We performed a retrospective cohort study of consecutive patients <21 years old who underwent primary HTx between 2013 and 2017. Multiorgan transplants were excluded. The presence of atypical infiltrates and burden of atypical infiltrates (rare vs predominant) on EMB were recorded. Primary outcome was a composite of cardiac allograft vasculopathy, graft failure (relisting or retransplant), or death. Presence of atypical infiltrates was evaluated: (1) overall using Cox regression with time-dependent covariates and (2) if present by 1 year post-HTx using Kaplan-Meier analysis. RESULTS: Atypical infiltrates were present in 24 out of 95 patients (25%) and were associated with a higher likelihood of reaching the composite outcome (hazard ratio (HR) 6.22, 95% confidence interval (CI) 2.60-14.89, p < 0.0001). This persisted when controlling for rejection in multivariable analysis. There was also a greater risk of the composite outcome if ≥2 nonconsecutive EMBs had atypical infiltrates (HR 11.80, 95%CI 3.17-43.84, p = 0.0002) or if atypical infiltrates were the predominant feature on EMB (HR 30.58, 95%CI 9.34-100.06, p < 0.0001). Patients with atypical infiltrates by 1-year post-HTx had a 5-year freedom from the composite outcome of 48%, compared to 90% if no atypical infiltrates had been present by this timepoint (log rank p = 0.002). CONCLUSIONS: The presence of atypical infiltrates on EMB is associated with significantly worse outcomes in children following HTx. These patients require closer follow-up to assess for developing graft dysfunction.

External assessment and refinement of a population pharmacokinetic model to guide tacrolimus dosing in pediatric heart transplant.

STUDY OBJECTIVE: The immunosuppressant tacrolimus is a first-line agent to prevent graft rejection following pediatric heart transplant; however, it suffers from extensive inter-patient variability and a narrow therapeutic window. Personalized tacrolimus dosing may improve transplant outcomes by more efficiently achieving and maintaining therapeutic tacrolimus concentrations. We sought to externally validate a previously published population pharmacokinetic (PK) model that was constructed with data from a single site. DATA SOURCE: Data were collected from Seattle, Texas, and Boston Children's Hospitals, and assessed using standard population PK modeling techniques in NONMEMv7.2. MAIN RESULTS: While the model was not successfully validated for use with external data, further covariate searching identified weight (p < 0.0001 on both volume and elimination rate) as a model-significant covariate. This refined model acceptably predicted future tacrolimus concentrations when guided by as few as three concentrations (median prediction error = 7%; median absolute prediction error = 27%). CONCLUSION: These findings support the potential clinical utility of a population PK model to provide personalized tacrolimus dosing guidance.

Adaptations of paediatric cardiology practice during the COVID-19 pandemic.

During the initial surge of the COVID-19 pandemic in the spring and summer of 2020, paediatric heart centres were forced to rapidly alter the way patient care was provided to minimise interruption to patient care as well as exposure to the virus. In this survey-based descriptive study, we characterise changes that occurred within paediatric cardiology practices across the United States and described provider experience and attitudes towards these changes during the pandemic. Common changes that were implemented included decreased numbers of procedures, limiting visitors and shifting towards telemedicine encounters. The information obtained from this survey may be useful in guiding and standardising responses to future public health crises.

Redefining the Relationship: Palliative Care in Critical Perinatal and Neonatal Cardiac Patients.

Patients with perinatal and neonatal congenital heart disease (CHD) represent a unique population with higher morbidity and mortality compared to other neonatal patient groups. Despite an overall improvement in long-term survival, they often require chronic care of complex medical illnesses after hospital discharge, placing a high burden of responsibility on their families. Emerging literature reflects high levels of depression and anxiety which plague parents, starting as early as the time of prenatal diagnosis. In the current era of the global COVID-19 pandemic, the additive nature of significant stressors for both medical providers and families can have catastrophic consequences on communication and coping. Due to the high prognostic uncertainty of CHD, data suggests that early pediatric palliative care (PC) consultation may improve shared decision-making, communication, and coping, while minimizing unnecessary medical interventions. However, barriers to pediatric PC persist largely due to the perception that PC consultation is indicative of "giving up." This review serves to highlight the evolving landscape of perinatal and neonatal CHD and the need for earlier and longitudinal integration of pediatric PC in order to provide high-quality, interdisciplinary care to patients and families.

Pediatric Palliative Care in the Heart Failure, Ventricular Assist Device and Transplant Populations: Supporting Patients, Families and Their Clinical Teams.

Heart failure is a life-changing diagnosis for a child and their family. Pediatric patients with heart failure experience significant morbidity and frequent hospitalizations, and many require advanced therapies such as mechanical circulatory support and/or heart transplantation. Pediatric palliative care is an integral resource for the care of patients with heart failure along its continuum. This includes support during the grief of a new diagnosis in a child critically ill with decompensated heart failure, discussion of goals of care and the complexities of mechanical circulatory support, the pensive wait for heart transplantation, and symptom management and psychosocial support throughout the journey. In this article, we discuss the scope of pediatric palliative care in the realm of pediatric heart failure, ventricular assist device (VAD) support, and heart transplantation. We review the limited, albeit growing, literature in this field, with an added focus on difficult conversation and decision support surrounding re-transplantation, HF in young adults with congenital heart disease, the possibility of destination therapy VAD, and the grimmest decision of VAD de-activation.

Pediatric heart-liver transplant outcomes in the United States: A 25-year National Cohort Study.

BACKGROUND: Pediatric HLT remains uncommon in the United States and criteria for HLT are unclear. The objectives of this study were to review the indications, and outcomes of pediatric HLT. METHODS: Data from the Scientific Registry of Transplant Recipients heart and liver databases were used to identify 9245 pediatric isolated heart transplants (PHT), 14 134 pediatric isolated liver transplant (PLT), and 20 pediatric HLT (16 patients underwent sHLT [same organ donor] and four patients with a history of PHT followed by PLT [different organ donors]; age ≤21 years) between 1992 and 2017. Outcomes included patient survival, and 1-year rates of acute heart and liver rejection. RESULTS: The median age for pediatric HLT was 15.6 (IQR: 10.5, 17.9) years, and included 12 males (12/20 = 60%). In the HLT group, the most common indication for HT was CHD (12/20 = 60%), and the most common indication for liver transplant was cirrhosis (9/20 = 45%). The 1, 3, and 5 year actuarial survival rates in pediatric simultaneous HLT recipients (n = 16) were 93%, 93%, and 93%, respectively, and was similar to isolated PHT alone (88%, 81%, and 75.5%, respectively and isolated PLT alone (84%, 82%, and 80%), respectively. There was no heart or liver rejection reported in the HLT group versus 9.9% in heart and 10.6% in liver transplant-only groups, respectively. CONCLUSION: Pediatric HLT is an uncommon but acceptable option for recipients with combined end-organ failure, with intermediate survival outcomes comparable to those of single-organ recipients.

Venous duct stenting in a 940-gram infant with infradiaphragmatic total anomalous pulmonary venous return.

An extremely low birthweight infant (940 grams) with a rare variant of obstructed infracardiac total anomalous pulmonary venous return underwent stenting of the venous duct as bridge to later surgical intervention. While technically challenging, this procedure represents a bridge to surgery for infants who might otherwise not be surgical candidates.

Telehealth for Pediatric Cardiology Practitioners in the Time of COVID-19.

Due to the COVID-19 pandemic, there has been an increased interest in telehealth as a means of providing care for children by a pediatric cardiologist. In this article, we provide an overview of telehealth utilization as an extension of current pediatric cardiology practices and provide some insight into the rapid shift made to quickly implement these telehealth services into our everyday practices due to COVID-19 personal distancing requirements. Our panel will review helpful tips into the selection of appropriate patient populations and specific cardiac diagnoses for telehealth that put patient and family safety concerns first. Numerous practical considerations in conducting a telehealth visit must be taken into account to ensure optimal use of this technology. The use of adapted staffing and billing models and expanded means of remote monitoring will aid in the incorporation of telehealth into more widespread pediatric cardiology practice. Future directions to sustain this platform include the refinement of telehealth care strategies, defining best practices, including telehealth in the fellowship curriculum and continuing advocacy for technology.

Association of Wolff-Parkinson-White With Left Ventricular Noncompaction Cardiomyopathy in Children.

BACKGROUND: Wolff-Parkinson-White (WPW) has been associated with left ventricular noncompaction (LVNC) in children. Little is known about the prevalence of this association, clinical outcomes, and treatment options. METHODS: Retrospective review of subjects with LVNC. LVNC was defined by established criteria; those with congenital heart disease were excluded. Electrocardiograms (ECGs) were reviewed for presence of pre-excitation. Outcomes were compared between those with isolated LVNC and those with WPW and LVNC. RESULTS: A total of 348 patients with LVNC were identified. Thirty-eight (11%) were found to have WPW pattern on ECG, and 84% of those with WPW and LVNC had cardiac dysfunction. In Kaplan-Meier analysis, there was significantly lower freedom from significant dysfunction (ejection fraction ≤ 40%) among those with WPW and LVNC (P < .001). Further analysis showed a higher risk of developing significant dysfunction in patients with WPW and LVNC versus LVNC alone (hazard ratio 4.64 [2.79, 9.90]). Twelve patients underwent an ablation procedure with an acute success rate of 83%. Four patients with cardiac dysfunction were successfully ablated, 3 having improvement in function. CONCLUSION: WPW is common among children with LVNC and is associated with cardiac dysfunction. Ablation therapy can be safely and effectively performed and may result in improvement in function.

Predictors and Consequences of Pediatric Hypertension: Have Advanced Echocardiography and Vascular Testing Arrived?

PURPOSE OF REVIEW: Pediatric hypertension is relatively common and associated with future adult hypertension. Elevated blood pressure in youth predicts future adult cardiovascular disease and blood pressure control can prevent progression of pediatric kidney disease. However, pediatric blood pressure is highly variable within a given child and among children in a population. RECENT FINDINGS: Therefore, modalities to index aggregate and cumulative blood pressure status are of potential benefit in identifying youth in danger of progression from a risk factor of subclinical phenotypic alteration to clinically apparent event. In this review, we advocate for the health risk stratification roles of echocardiographically assessed cardiac remodeling, arterial stiffness assessment, and assessment by ultrasound of arterial thickening in children and adolescents with hypertension.

Left atrial mechanics in children: insights from new applications of strain imaging.

Our principal aim was to describe functional changes in dilated left atrium (LA) of children by using new applications of LA strain. We studied 66 patients (age range 0.2-22 years) consisting of 33 with LA enlargement. We utilized speckle-tracking imaging for assessment LA longitudinal strain (S) and longitudinal displacement (D). S-D loops were generated by plotting S and D data along Y and X axes, respectively. We also measured noninvasive LA stiffness index, [Formula: see text] (%-1). Peak S in controls was 51.16 ± 19.45% versus 23.16 ± 13.66% in dilated LA (p < 0.0001). S-D loops in dilated LA group were significantly smaller compared to controls (2.62 ± 2.88 units vs. 5.24 ± 4.00 units, p < 0.01). Noninvasive LA stiffness index was higher in dilated LA group (0.77 ± 0.63%-1 vs. 0.17 ± 0.07%-1, p < 0.0001). A cut-off LA stiffness value of 0.25%-1 was found to maximize sensitivity and specificity (84.0% and 84.85%, respectively). Children with enlarged LA demonstrate decreased peak S, abnormal S-D loops and increased LA stiffness, providing a newer insight into LA function. Evaluation of LA mechanics may be applied in future as a surrogate for left ventricular filling parameters.

Right atrial mechanics provide useful insight in pediatric pulmonary hypertension.

Right atrial (RA) mechanics have been studied infrequently in children in the past due to technical constraints. With the advent of strain imaging, RA physiology can now be studied in greater detail. The principal aim of this study was to describe functional changes in right heart mechanics of children with idiopathic pulmonary arterial hypertension (PAH), by using new applications of RA strain. In this retrospective study, we evaluated RA mechanics of 20 patients (age range = 3-23 years) with PAH and 18 control patients. RA longitudinal strain (RALS) and longitudinal displacement (LD) were calculated by speckle-tracking echocardiography. RALS was plotted against LD, producing a characteristic strain-displacement (S-D) loop. Standard indices of right heart function and right heart catheterization data were obtained. Patients were clinically subdivided into "compensated" and "decompensated" PAH. A chart review was performed to identify patients who subsequently developed adverse outcomes, including death, awaiting or received lung and/or heart transplantation. RALS was significantly lower in decompensated PAH compared with both controls and compensated PAH. Area enclosed by S-D loops differed significantly between the compensated and decompensated PAH subgroups (5.33 [3.90-9.44] versus 1.83 [1.17-2.36], P < 0.05). S-D loop area and RALS possessed high sensitivity and specificity compared to other parameters for identifying children with PAH who subsequently developed adverse outcomes. In particular, their sensitivities and specificities were greatly superior compared to those of tricuspid annular plane systolic excursion (TAPSE). RALS may represent a useful metric for assessing right ventricular (RV) dysfunction. S-D loops, composed over an entire cardiac cycle, may present useful, composite information regarding both systolic and diastolic right heart function. RA mechanics may serve as useful tools for identifying patients with more severe PAH, who are at risk for future adverse outcomes associated with RV failure.

Fgf signaling governs cell fate in the zebrafish pineal complex.

Left-right (L-R) asymmetries in neuroanatomy exist throughout the animal kingdom, with implications for function and behavior. The molecular mechanisms that control formation of such asymmetries are beginning to be understood. Significant progress has been made by studying the zebrafish parapineal organ, a group of neurons on the left side of the epithalamus. Parapineal cells arise from the medially located pineal complex anlage and migrate to the left side of the brain. We have found that Fgf8a regulates a fate decision among anterior pineal complex progenitors that occurs just prior to the initiation of leftward migration. Cell fate analysis shows that in the absence of Fgf8a a subset of cells in the anterior pineal complex anlage differentiate as cone photoreceptors rather than parapineal neurons. Fgf8a acts permissively to promote parapineal fate in conjunction with the transcription factor Tbx2b, but might also block cone photoreceptor fate. We conclude that this subset of anterior pineal complex precursors, which normally become parapineal cells, are bipotential and require Fgf8a to maintain parapineal identity and/or prevent cone identity.

Subnuclear development of the zebrafish habenular nuclei requires ER translocon function.

The dorsal habenular nuclei (Dh) of the zebrafish are characterized by significant left-right differences in gene expression, anatomy, and connectivity. Notably, the lateral subnucleus of the Dh (LsDh) is larger on the left side of the brain than on the right, while the medial subnucleus (MsDh) is larger on the right compared to the left. A screen for mutations that affect habenular laterality led to the identification of the sec61a-like 1(sec61al1) gene. In sec61al1(c163) mutants, more neurons in the LsDh and fewer in the MsDh develop on both sides of the brain. Generation of neurons in the LsDh occurs more rapidly and continues for a longer time period in mutants than in WT. Expression of Nodal pathway genes on the left side of the embryos is unaffected in mutants, as is the left sided placement of the parapineal organ, which promotes neurogenesis in the LsDh of WT embryos. Ultrastructural analysis of the epithalamus indicates that ventricular precursor cells, which form an epithelium in WT embryos, lose apical-basal polarity in sec61al1(c163) mutants. Our results show that in the absence of sec61al1, an excess of precursor cells for the LsDh exit the ventricular region and differentiate, resulting in formation of bilaterally symmetric habenular nuclei.