COVID-19 Vaccines in the Pediatric Population: A Focus on Cardiac Patients.

Due to the deleterious global impact of the COVID-19 pandemic, tremendous effort has been invested in the development of vaccines against the virus. Vaccine candidates are first tested in adult populations, a number of which have been approved for EUL by the WHO, and are in use across the USA and MENA region. The question remains whether these (or other) vaccines should be recommended to a neonatal, pediatric, and/or adolescent cohort. Incidence and severity of COVID-19 infection are low in pediatric, neonatal, and adolescent patients. Since both overall incidence and severity are lower in children than in adults, safety is an important consideration in vaccine approval for these age groups, in addition to efficacy and a decreased risk of transmission. The following review discusses vaccine immunology in children aged 0-18 years, with emphasis on the negative impact of the COVID-19 pandemic on the lives of children, considerations for pediatric vaccine approval, and available vaccines for pediatric cohorts along with a breakdown of the efficacy, advantages, and disadvantages for each. This review also contains current and future perspectives, as well as a section on the cardiovascular implications and related dynamics of pediatric COVID-19 vaccination.

Pulmonary artery banding: a 20-year experience at a tertiary care center in a developing country.

Aim: Pulmonary artery banding serves as an important palliative procedure used for the management of several congenital heart lesions. This study aims to describe a 20-year experience of pulmonary artery banding at a tertiary care center in a developing country. Methods: This is a retrospective chart review of patients who underwent pulmonary artery banding over a 20-year period between January 2000 and July 2020 in a tertiary care center in a developing country. Data regarding demographics, indications, diagnosis, echocardiographic findings, postoperative complications, hospital stay, and outcomes were recorded. Results: A total of 143 patients underwent pulmonary artery banding between 2000 and 2020, with a decrease from approximately 15 surgeries per year in 2012 to 1-2 surgeries a year in 2020. At the time of banding, the median age of patients was approximately 90 days [interquartile range, IQR, 30-150 days]. Four patients (2.8%) died during the band placement. No significant association was observed between baseline characteristics or type of heart defect at presentation and postoperative morbidity and mortality. Conclusion: Pulmonary artery banding remains useful in a subset of congenital heart lesions and as a surgical palliation, with relatively low mortality, allowing postponement of total correction to a higher weight. This technique continues to be valuable in developing countries or for heart surgical programs with limited resources.

Hybrid stage 1 palliation for HLHS: the experience of a tertiary center in a developing country.

Background: Hypoplastic left heart syndrome (HLHS) accounts for 2.6% of congenital heart disease and is an invariably fatal cardiac anomaly if left untreated. Approximately 33,750 babies are born annually with HLHS in developing countries. Unfortunately, the majority will not survive due to the scarcity of resources and the limited availability of surgical management. Aim: To describe and analyze our experience with the hybrid approach in the management of HLHS in a developing country. Methods: We performed a retrospective single-center study involving all neonates born with HLHS over five years at the Children's Heart Center at the American University of Beirut. The medical records of patients who underwent the hybrid stage 1 palliation were reviewed, and data related to baseline characteristics, procedure details and outcomes were collected to describe the experience at a tertiary care center in a developing country. Results: A total of 18 patients were diagnosed with HLHS over a five-year period at our institution, with male to female ratio of 1:1. Of those, eight patients underwent the hybrid stage I procedure. The mean weight at the time of the procedure was 3.3 ± 0.3 kg with an average age of 6.4 ± 4 days. The mean hospital length of stay was 27.25 days, with an interquartile range of 33 days. The cohort's follow-up duration averaged 5.9 ± 3.5 years. The surgical mortality was zero. Only one mortality was recorded during the interstage period between stage I and II and was attributed to sepsis. Notably, all surviving patients maintained preserved and satisfactory cardiac function with good clinical status. Conclusion: Our limited experience underscores the potential of developing countries with proper foundations to adopt the hybrid procedure for HLHS, yielding outcomes on par with those observed in developed countries. This demonstrates the viability of establishing a more balanced global landscape for children with congenital heart disease.

NT-proBNP cardiac value in COVID-19: a focus on the paediatric population.

NT-proBNP is a peptide related to brain natriuretic peptide, a cardiac biomarker and a member of the natriuretic family of peptides. NT-proBNP has demonstrated its clinical utility in the assessment of a wide spectrum of cardiac manifestations. It is also considered a more precise diagnostic and prognostic cardiac biomarker than brain natriuretic peptide. With the appearance of the Severe Acute Respiratory Syndrome Coronavirus 2 virus and the subsequent COVID-19 pandemic, diagnosis of heart implications began to pose an increasing struggle for the physician. Echocardiography is considered a central means of evaluating cardiac disorders like heart failure, and it is considered a reliable method. However, other diagnostic methods are currently being explored, one of which involves the assessment of NT-proBNP levels. In the literature that involves the adult population, significant positive correlations were drawn between the levels of NT-proBNP and COVID-19 outcomes such as high severity and fatality. In the paediatric population, however, the literature is scarce, and most of the investigations assess NT-proBNP in the context of Multiple Inflammatory Syndrome in Children, where studies have shown that cohorts with this syndrome had elevated levels of NT-proBNP when compared to non-syndromic cohorts. Thus, more large-scale studies on existing COVID-19 data should be carried out in the paediatric population to further understand the prognostic and diagnostic roles of NT-proBNP.

Newborn Pulse Oximetry Screening for Detecting Congenital Heart Disease: Experience at a Tertiary Care Center.

Background: Congenital heart disease (CHD) remains the number one birth defect worldwide. Pulse oximetry screening (POS) is a widely used CHD screening modality effective in detecting critical lesions. This study is aimed at assessing the accuracy and cost-effectiveness of POS in a cohort of term well-babies admitted to a regular nursery in a tertiary care center. Methods: We reviewed the charts of term babies admitted to our regular nursery over a period of one year. The results of POS and the findings of echocardiography were collected. Similarly, we explored the records of our fetal echocardiography program to identify the fetuses screened for CHD during the same period. Results: 900 term babies were born and admitted to newborn nursery at our center, and 69 fetuses were evaluated by our fetal cardiology team during the study period. None of our term babies had a positive POS at birth or 24 hours of age. However, 56 babies had a cardiac echo before hospital discharge due to suspicious findings on physical examination or a family history of CHD. A simple noncritical CHD was noted in 10 of them. Additionally, 53 babies underwent echocardiography within the first five years of life; a simple CHD was noted in 6 of them. In parallel, 21 of our fetuses were found to have CHD: 16 simple CHD and 5 critical CHD (CCHD). Conclusion: Despite its cost-effectiveness and efficacy in screening for CCHD, POS is suboptimal for detecting simple CHD. In the absence of a proper prenatal screening and fetal echocardiography program, POS remains a cost-effective modality for detecting CCHD.

COVID-19 in congenital heart disease patients: what did we learn?!

Aim: COVID-19 pandemic has spread widely at unpreceded pace. Cardiovascular comorbidities are significantly correlated with severe and critical illness. Nevertheless, studies examining the impact of congenital heart disease on COVID-19 severity are scarce and restricted to hospitalized patients. This study aims to explore the course of COVID-19 illness, severity and complications in patients with concomitant congenital heart disease. Methodology: This study is a cross sectional survey that includes patients with congenital heart disease who are registered at the Children Heart Center at the American University of Beirut Medical Center. The survey was conducted in the pediatric cardiology outpatient clinics or remotely via phone calls. Results: A total of 238 patients participated in the study, of which 47.9% had suspected or confirmed diagnosis of SARS-CoV-2 infection. The majority of patients had mild illness. The symptoms ranged between rhinorrhea (15.6%), cough (15.6%), low-grade fever (11.2%), anosmia (2.7%), ageusia (2.5%), headache (9.8%), high-grade fever (8.5%), gastrointestinal symptoms (7.6%), lethargy (6.3%), muscle aches (5.6%), difficulty breathing (5.4%), joint pain (4.7%), and chills (4.7%). 20% of the surveyed patients required treatment at home. Hospitalization and oxygen therapy was required in 3.5% of cases, while only 1.5% demanded intensive care admission. Only one fatality was encountered. Conclusion: COVID-19 infection in pateints with congenital heart disease exhibits a mild to moderate course, and doesn't necessarily increase risk of complicated disease. No correlation could be found between specific congenital heart lesion and disease severity.

Pathogenesis and distribution of infective endocarditis in the pediatric population: a 20-year experience in a tertiary care center in a developing country.

Introduction: Infective endocarditis is an infection of the endothelial surfaces of the heart. It is more prevalent in adults but its incidence in the pediatric population has been on the rise. The most important factor remains congenital heart disease and the most isolated pathogen is viridans group streptococcus. Methods: In this manuscript, we present a 20-year experience of a major referral tertiary care center in diagnosing and treating pediatric patients with endocarditis. A retrospective analysis of records of patients who were diagnosed with infective endocarditis under the age of 18 years is presented in this study. Variables relating to the demographic, imaging, microbiologic and pathologic data are described. Outcomes relating to complications and need for surgical repair are also portrayed. Results: A total of 70 pediatric patients were diagnosed with endocarditis in this time interval. The medical records of 65 patients were comprehensively reviewed, however the remaining 5 patients had severely missing data. Of the 65 patients, 55.4% were males, and the mean age at diagnosis was 7.12 years. More than half of the population (58.5%) had vegetation evident on echocardiography. The pulmonary valve was the most commonly affected (50%), followed by the mitral valve and tricuspid valves (15.6%). Most patients received empiric treatment with vancomycin and gentamicin. Viridans group streptococcus was the most frequently isolated organism (23.4%). Conclusion: Among pediatric patients diagnosed with endocarditis in this study, data pertaining to valve involvement and microbiologic information was consistent with the published literature. The incidence of complications and the need for surgical repair are not significantly correlated with demographic and clinical variables.

Combined tricuspid atresia- AV septal defect-a rare congenital cardiac abnormality.

INTRODUCTION: Congenital heart diseases (CHDs) are one of the most common birth defects worldwide with a prevalence of 1%. CHDs can be classified into cyanotic and acyanotic diseases based on the presence or absence of the characteristic bluish discoloration of skin and mucus membranes. A subset of cyanotic diseases is single ventricle malformations. This group of disorders comprises 1% of all CHDs. A remarkable yet rare and underreported entity of single ventricle malformations is combined tricuspid atresia (TA) and atrioventricular (AV) septal defect which is characterized by the anatomical features of both entities. Combined TA-AV septal malformation was first anatomically described in 1953 and further explored through echocardiography and cardiac catheterization in 1987 and then 1991. Since then, no studies have been documented in the literature prompting us to share our findings. METHODS: Herein we are describing a rare and underreported cardiac lesion based of a retrospective revision of medical charts at the American University of Beirut Medical Center (AUBMC) Children's Heart Center, a tertiary medical center in the Middle East RESULTS: Out of 200 cases with confirmed single ventricle physiology, we identified a few patients with characteristics of combined TA-AV septal defect. Our patients exhibited characteristic echocardiographic findings of primum ASD, VSD, atretic RAVV, and clefted LAVV. CONCLUSION: In short, TA-AV septal defect is a rare, underreported congenital malformation. Tracking our patients' clinical profiles will help improve our understanding of the prognosis of this entity. Our findings may also improve treatment modalities since replacing the left-sided valve is often overlooked if the defect is inaccurately diagnosed. In addition, such findings can help shed light on the embryological development of the rarely encountered variation of AV septal malformation.

Corticosteroids in COVID-19: pros and cons.

The wide and rapid spread of the COVID-19 pandemic has placed an unanticipated burden on the global healthcare sector. This necessitated a swift response from the international community to reach a solution. Efforts were made in parallel to develop preventative and therapeutic modalities. Since then, drug repurposing has blossomed as a potentially rapid resolution and has included various agents with anti-viral and anti-inflammatory properties. Corticosteroids, being potent anti-inflammatory agents, have been placed under extensive investigation. Various trials have recorded the beneficial outcome of corticosteroids in decreasing the mortality and morbidity of COVID-19. With the high pace of escalating events, the quality and study design of clinical trials are varied. Therefore, this study aims to explore the role of corticosteroids in COVID-19 disease. It inspects the molecular, pharmacologic, and clinical proof behind this theory.

Myocarditis in COVID-19: a focus on the pediatric population.

The emergence of the novel SARS-CoV-2 virus in late 2019 introduced new, unpreceded global challenges. Complications arising from COVID-19 widely range from mild to severe and, in some cases, lead to death. The myocardium has proven to be a potential target site for this virus, and has been affected at various levels, resulting in numerous complications, including myocarditis. This article represents a thorough and updated literature review on the clinical manifestations of COVID-19 that pertain to myocarditis, its molecular basis, diagnostic modalities, and treatment approaches, with a special focus on the pediatric population. There definitely is a link between COVID-19 and myocarditis, but the manifestations of this relationship vary from one case to another. At the molecular level, various viral and immunologic factors contribute to the development of myocarditis. Diagnosis, treatment, and outcomes vary as well, but some common trends can be noted. Proper and prompt diagnosis and treatment of SARS-CoV-2-induced myocarditis are crucial. Unfortunately, data in the literature suffers from conspicuous scarcity, especially for the pediatric population; thus, further large-scale clinical studies are required to attain clear and effective guidelines.

Multisystem inflammatory syndrome in children: another COVID-19 sequel.

With the rapid expansion of the COVID-19 pandemic, the disease burden and its consequences on the paediatric population has been progressively recognised. Although COVID-19 infection in children presents as asymptomatic to mild illness, instances of hyperinflammation and multi-organ involvement following the viral infection have been described. This condition, known as the multisystem inflammatory syndrome in children (MIS-C), has gained a wide global attention. Despite the global efforts to uncover the disease characteristics and management, a clear pathogenesis and a unified treatment regimen have not been reached yet. This paper tackles the epidemiology of the MIS-C, discusses its suggested pathogenesis, drives through its varying clinical presentations, and evaluates the different treatment regimens employed in managing MIS-C.

Low molecular weight heparin in COVID-19: benefits and concerns.

Since its emergence, the COVID-19 pandemic had a dramatic impact on the public health worldwide and it scarred the medical, economical, and social determinants of health. Even after the significant vaccination advances, the disease of SARS-CoV-2 can manifest in severe presentations with life-threatening thromboembolic and multi-organ complications leading to notable morbidity and mortality. Clinicians and researchers are on continuous pursuit of investigating different approaches in the attempt to prevent the infection and minimize its severity. Although the COVID-19's pathophysiology remains relatively unclear, it is well established now that coagulopathy, systemic thrombotic propensity, and a robust immunoinflammatory response are some of the most important determinants of its morbidity and mortality. Accordingly, research efforts have focused on addressing the inflammatory and hematological cascades using available agents to avoid thromboembolic events. Several studies and investigators have emphasized the importance of Low molecular weight heparin (LMWH), namely, Lovenox, in addressing these sequelae of the COVID-19 disease, either prophylactically or therapeutically. This review explores the benefits and concerns of employing LMWH, a widely used anticoagulant, in COVID-19 disease. It delves into Enoxaparin as a molecule, along with its pharmacology, mechanism of action, and clinical uses. It also reviews the current high-quality clinical evidence that highlight the role of enoxaparin in SARS-CoV-2 infection.

COVID-19 in Cyanotic Congenital Heart Disease.

Congenital heart disease (CHD) is the most prevalent congenital defect in newborn infants. Due to the various types of heart abnormalities, CHD can have a wide range of symptoms. Cardiac lesions comprise a range of different types and accordingly varying severities. It is highly helpful to classify CHD into cyanotic and acyanotic heart diseases. In this review, we are investigating the course of Coronavirus disease 2019 (COVID-19) in cyanotic CHD patients. The infection may directly or indirectly affect the heart by affecting the respiratory system and other organs. The effect on the heart that is pressure- or volume-overloaded in the context of CHD is theoretically more severe. Patients with CHD are at a higher risk of mortality from COVID-19 infection or suffering worse complications. While the anatomic complexity of CHD does not seem to predict the severity of infection, patients with worse physiological stages are more susceptible such as cyanosis and pulmonary hypertension. Patients with CHD exhibit continuous hypoxemia and have lower oxygen saturations because of a right-to-left shunt. Such individuals run the danger of rapidly deteriorating in the event of respiratory tract infections with inadequate oxygenation. Additionally, these patients have a higher risk of paradoxical embolism. Hence, critical care should be given to cyanotic heart disease patients with COVID-19 in comparison to acyanotic patients and this is through proper management, close observation, and adequate medical therapy.

Tamponade and massive pleural effusions secondary to peripherally inserted central catheter in neonates-A complication to be aware of.

Background: Peripherally inserted central catheters (PICC) are frequently used in neonatal intensive care units (NICU) to assist premature and critically ill neonates. Massive pleural effusions, pericardial effusions, and cardiac tamponade secondary to PICC are extremely uncommon but have potentially fatal consequences. Objective: This study investigates the incidence of tamponade, large pleural, and pericardial effusions secondary to peripherally inserted central catheters in a neonatal intensive care unit at a tertiary care center over a 10-year period. It explores possible etiologies behind such complications and suggests preventative measures. Study design: Retrospective analysis of neonates who were admitted to the NICU at the AUBMC between January 2010 and January 2020, and who required insertion of PICC. Neonates who developed tamponade, large pleural, or pericardial effusions secondary to PICC insertion were investigated. Results: Four neonates developed significant life-threatening effusions. Urgent pericardiocentesis and chest tube placement were required in two and one patients, respectively. No fatalities were encountered. Conclusion: The abrupt onset of hemodynamic instability without an obvious cause in any neonate with PICC in situ should raise suspicion of pleural or pericardial effusions. Timely diagnosis through bedside ultrasound, and prompt aggressive intervention are critical.

Congenital heart disease research landscape in the Arab world: a 25-year bibliometric review.

Background: While research on congenital heart disease has been extensively conducted worldwide, comprehensive studies from developing countries and the Arab world remain scarce. Aim: This study aims to perform a bibliometric review of research on congenital heart disease in the Arab world from 1997 to 2022. Methods: We analyzed data from the Web of Science, encompassing various aspects such as topics, countries, research output, citations, authors, collaborations, and affiliations. This comprehensive science mapping analysis was done using the R statistical software's Bibliometrix Package. Results: The research output from Arab countries over the 25 years showed an average annual growth rate of 11.5%. However, Arab countries exhibited lower research productivity than the United States and Europe, with a 24-fold difference. There was substantial variation in research output among 22 Arab countries, with five countries contributing to 78% of the total publications. Most of the published research was clinical, with limited innovative contributions and a preference for regional journals. High-income Arab countries displayed higher research productivity and citation rates than their low-income developing counterparts. Despite being categorized as upper-middle-income, post-conflict countries exhibited low research productivity. About one-quarter of the published articles (26%) resulted from collaborative efforts among multiple countries, with the United States being the most frequent collaborator. Enhanced research productivity and impact output were strongly associated with increased international cooperation. Conclusion: Research productivity in the Arab region closely correlates with a country's GDP. Success hinges on governmental support, funding, international collaboration, and a clear research vision. These findings offer valuable insights for policymakers, educational institutions, and governments to strengthen research programs and nurture a research culture.

The use of steroids in treating chylothorax following cardiac surgery in children: a unique perspective.

BACKGROUND: Chylothorax is the accumulation of chyle fluid in the pleural space. The incidence of chylothorax is quite common post-cardiac surgeries in pediatrics especially in Fontan procedures. Although several treatment lines are known for the management of chylothorax, steroids were scarcely reported as a treatment option. We present a unique case of a 4-year-old child who underwent Fontan procedure and suffered a long-term consequence of chylothorax. The chylothorax only fully resolved after introducing corticosteroids as part of her management. METHODS: A literature review about management of chylothorax post-cardiac surgery in children using Ovid Medline (19462021), PubMed, and google scholar was performed. CONCLUSION: Conservative management without additional surgical intervention is adequate in most patients. Additionally, somatostatin can be used with variable success rate. However, a few cases mentioned using steroids in such cases. More research and reporting on the use of steroids in the treatment of chylothorax post-cardiac surgeries in children is needed to prove its effectivity. In this article, we describe a case of chylothorax post-Fontan procedure that supports the use of steroids.

Aspirin in COVID-19: Pros and Cons.

Since its emergence, the COVID-19 pandemic has been ravaging the medical and economic sectors even with the significant vaccination advances. In severe presentations, the disease of SARS-CoV-2 can manifest with life-threatening thromboembolic and multi-organ repercussions provoking notable morbidity and mortality. The pathogenesis of such burdensome forms has been under extensive investigation and is attributed to a state of immune dysfunction and hyperinflammation. In light of these extraordinary circumstances, research efforts have focused on investigating and repurposing previously available agents that target the inflammatory and hematological cascades. Aspirin, due to its well-known properties and multiple molecular targets, and ought to its extensive clinical use, has been perceived as a potential therapeutic agent for COVID-19. Aspirin acts at multiple cellular targets to achieve its anti-inflammatory and anti-platelet effects. Although initial promising clinical data describing aspirin role in COVID-19 has appeared, evidence supporting its use remains fragile and premature. This review explores the notion of repurposing aspirin in COVID-19 infection. It delves into aspirin as a molecule, along with its pharmacology and clinical applications. It also reviews the current high-quality clinical evidence highlighting the role of aspirin in SARS-CoV-2 infection.

Endovascular Stent Repair of Aortic Coarctation in a Developing Country: A Single-Center Experience.

BACKGROUND/PURPOSE: CoA remains one of the most common congenital heart diseases and is associated with significant morbidity and mortality and if untreated. We aim to evaluate the safety, feasibility, and outcomes of endovascular stenting of Coarctation of the aorta (CoA) in a developing country with limited resources and compare it to available benchmarks. MATERIALS/METHODS: A retrospectively review of all patients who underwent endovascular stent repair of aortic coarctation at our tertiary center since 2009 was done. RESULTS: 18 patients were identified, sixteen had native CoA, while two had recurrent CoA. mean age at the time of procedure was 21.2 ± 9.8 years (range 10-45 years), and 12(66%) patients were males. The mean follow-up duration was 4 ± 2.8 years. Post stenting, the average ascending-to-descending aorta systolic gradient decreased by 42.9 ± 20.4 mmHg (p < 0.001). After the intervention, 13(72.2%) patients achieved normal BP while 5(27.8%) had residual hypertension. Fourteen patients received bare-metal stents, and four had covered stents. Attempted stent implantation was successful in all patients. Our procedural success rate was 94%. On follow-up, no dissections or aneurysmal changes were detected, four patients underwent re-expansion of the stent, one patient with suboptimal stenting result required surgery 6 months after stenting, and two patients had minor post-operative complications. CONCLUSIONS: Endovascular stenting for de-novo or recurrent CoA in children and adults at a tertiary center in a developing country is feasible and safe with outcomes comparable to developed countries. A multidisciplinary team approach is paramount in achieving good results and low complication rates in limited-resource settings.

Multisystem inflammatory syndrome in children (MIS-C) and "Near MIS-C": A continuum?

Introduction: Reports of multisystem inflammatory syndrome in children (MIS-C), following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, have been increasing worldwide, with an incidence varying significantly across studies based on the definition used for the diagnosis. At our tertiary medical center in Lebanon, we encountered several cases that presented a diagnostic challenge because they mimicked MIS-C but did not meet the US Centers for Disease Control and Prevention (CDC) definition. We decided to review these cases and describe their features in comparison with cases that met the CDC criteria of MIS-C and those that had an alternative diagnosis. Methods: This is a retrospective chart review of subjects aged <19 years old admitted to the American University of Beirut Medical Center (AUBMC) between March 1, 2020, and May 31, 2021, with suspected or confirmed MIS-C, following documented COVID-19 infection, with sufficient or insufficient criteria for diagnosis. Subjects were classified into 3 groups: "MIS-C", "Near MIS-C" and "Alternative Diagnosis". Results: A total number of 29 subjects were included in our cohort. Fever was present in all subjects. In the MIS-C group, evidence for cardiovascular system involvement was the most common feature followed by the mucocutaneous and gastrointestinal systems. In the "Near MIS-C" and "Alternative Diagnosis" group, gastrointestinal symptoms were the most common with only one patient with cardiac abnormalities and none with coagulopathy. Subjects with typical MIS-C presentation had higher inflammatory markers when compared to subjects in the other groups. Almost all the subjects had positive IgG for SARS-CoV-2. Of the 29 subjects, the Royal College of Paediatrics and Child Health (RCPCH) case definition would have identified all suspected cases without an alternative diagnosis as MIS-C, whereas the World Health Organization (WHO) and the CDC definitions would have excluded 6 and 10 subjects, respectively. Conclusion: MIS-C presents a diagnostic challenge due to the nonspecific symptoms, lack of pathognomonic findings, and potentially fatal complications. More research is needed to fully understand its pathogenesis, clinical presentation spectrum, and diagnostic criteria. Based on our experience, we favor the hypothesis that MIS-C has a continuum of severity that necessitates revisiting and unifying the current definitions.

Transcatheter occlusion of a hepatic vein-to-left atrium fistula: Should we close venovenous collateral vessels following Fontan operation?

Right-to-left shunt due to abnormal systemic venous drainage to the left heart is among the causes of hypoxemia following Fontan operation. There are conflicting data regarding the closure of the venovenous collaterals (VVCs) post-Fontan, showing decreased survival in older patients. In a child with visceral heterotaxy, we describe a rare fistula draining a right-sided hepatic vein into hepatic venous plexus and a right-sided pulmonary venous atrium. The patient presented with severe hypoxemia post-Fontan and underwent fistula occlusion with AMPLATZER™ Vascular Plug II, successfully improving hemodynamic status with resolution of the hypoxemia. Younger patients with cyanosis due to VVCs may benefit from percutaneous occlusion post-Fontan.