Paediatric dilated cardiomyopathy: clinical profile and outcome. The experience of a tertiary centre for paediatric cardiology

Burden of Renal Dysfunction and Neurologic Complications in Hospitalized Pediatric Heart Failure Unrelated to Congenital Heart Disease: A Multicenter Study

Objectives: Limited data are available on renal dysfunction and neurologic complications in heart failure in children, when the heart failure is not related to congenital heart disease (CHD) or cardiac surgery. This study used a multi-center database to describe pediatric heart failure (pHF)-related renal dysfunction, neurological complications, and outcomes in non-CHD patients. Methods: The Pediatric Health Information System (PHIS) database between 2004 and 2020 was used to analyze the prevalence of renal dysfunction and neurologic complications associated with pHF hospitalizations and their impact on outcomes. Results: Of the 5515 hospitalizations included in the study, renal dysfunction was identified in 1239 (22.5%), and neurologic dysfunction was diagnosed in 539 (9.8%). The diagnosis of renal or neurologic complications was associated with significantly higher use of ICU therapies, including mechanical ventilation, parenteral nutrition, and mechanical circulatory support. Patients with significant renal dysfunction were likely to receive kidney transplants in 3.1% of the cases. Neurologic complications were higher in patients with pHF who underwent heart transplantation (21.3% vs. 7.8%, p < 0.001). Patients with renal dysfunction and neurologic complications had significantly higher mortality rates than those without renal dysfunction (11.7% vs. 4.3%, p < 0.001) and neurologic complications (18.4% vs. 4.6%, p < 0.001). Conclusions: Renal dysfunction and neurologic complications are common, resulting in significantly higher utilization of ICU therapies and mortality rates during non-CHD-related pHF hospitalization. Neurologic complications associated with hospitalization for pHF are associated with a significantly higher mortality, which has been underemphasized in the literature. This study assesses the burden of these morbidities and highlights the importance of monitoring and managing renal and neurologic complications in pHF to improve outcomes.

Parameters affecting outcome of paediatric cardiomyopathies in the intensive care unit: experience of an Egyptian tertiary centre over 7 years

Introduction: Paediatric cardiomyopathies are rare but serious and often life-threatening conditions. In the absence of cardiac transplant and ventricular assist device as treatment options in our region, it is very important to identify patients at higher risk. The aim of this study was to determine the outcome of patients diagnosed with cardiomyopathies and their prognostic indicators. Patients and methods: This study included 92 cases representing all patients diagnosed with cardiomyopathy who were admitted into the pediatric cardiac intensive care unit during the period from January 2012 to September 2018. The patients were classified into two groups according to the outcome: the first group comprised 69 patients who survived, and the second group comprised 23 patients who died. All medical records were reviewed, and data were recorded and analysed. Results: Patients with cardiomyopathies represented 8.6% (92/1071) of all patients with cardiac diseases who were admitted in the study period and in the target age group (0.5-12 years). Dilated cardiomyopathy (DCM) was the most frequent type of cardiomyopathy among the admitted patients (80 patients), while 6 patients were diagnosed with hypertrophic cardiomyopathy (HCM), 4 were diagnosed with restrictive cardiomyopathy (RCM), and only 2 were diagnosed with mixed DCM-RCM. Seventy patients required inotropic support (76.1%). Assisted mechanical ventilation was used on 15 patients (16.3%). Twenty-three patients (25.0%) died during the 7-year study period. Conclusions Conclusions The occurrence of hypotension, abnormally high liver enzymes, the need for mechanical ventilation and the need for multiple inotropic drugs were found to be statistically significant predictors of mortality, while age, sex, fractional shortening, ejection fraction, presence of mitral regurgitation, mural thrombus, electrolyte disturbance and arrhythmias did not predict or affect patients' outcomes.

Clinical and biochemical footprints of inherited metabolic diseases. IV. Metabolic cardiovascular disease

Inherited metabolic diseases account for 15-20% of all cases of pediatric cardiomyopathy, with a high mortality of 15-47%. Metabolic diseases can also commonly be associated with other types of cardiovascular involvement such as arrhythmias, valvulopathy or vasculopathy. We reviewed and updated the list of known metabolic etiologies associated with cardiovascular involvement, and found 246 relevant inborn errors of metabolism. This represents the fourth of a series of articles attempting to create and maintain a comprehensive list of clinical and metabolic differential diagnoses according to system involvement.

Paediatric cardiomyopathies: echocardiographic diagnosis, clinical profile, and demographic characteristics: the experience of a tertiary referral centre for Latin American paediatric cardiology

BACKGROUND

Although multiple studies have been conducted in the adult population, there is a vast knowledge gap regarding the epidemiologic characteristics of cardiomyopathies in the paediatric population. This issue is even more crucial when the precarious situation of medical research in Latin America is considered. Given the potential impact that these disorders could have on Latin American health systems, a comprehensive epidemiologic study regarding the clinical profile and sociodemographic characteristics of these patients will influence the way we approach paediatric cardiomyopathies.

METHODS

An observational retrospective study was conducted at a tertiary referral centre for Colombian and Latin American paediatric cardiology. We analysed all cases of primary cardiomyopathies in children younger than 18 years of age who presented at our institution between 2010 and 2016. Cases of cardiomyopathies were classified according to World Health Organization guidelines.

RESULTS

From a total of 29,533 children who attended our institution during the study period, 89 new cases of primary cardiomyopathies were identified. The median age at diagnosis was 11 years (interquartile range 4-9). Dilated cardiomyopathy accounted for 57.3% (n = 51) of cases; hypertrophic cardiomyopathy, 12.3% (n = 11); restrictive cardiomyopathy, 8.9% (n = 8); non-compacted cardiomyopathy, 7.8% (n = 7); arrhythmogenic ventricular cardiomyopathy, 6.7% (n = 6); and unspecified cardiomyopathy, 6.7% (n = 6). Heart failure was observed in 53.93% of the patients. The overall mortality was 12.36% (n = 11), which included two of eight patients who underwent cardiac transplantation.

Systematic Review of PCR Proof of Parvovirus B19 Genomes in Endomyocardial Biopsies of Patients Presenting with Myocarditis or Dilated Cardiomyopathy

Background: Diverse viral infections have been associated with myocarditis (MC) and dilated cardiomyopathy (DCM). In this meta-analysis, we summarize the published results on the association of parvovirus B19 (B19V) genomes with human MC/DCM versus controls. Methods: n = 197 publications referring to B19V and MC or DCM were retrieved using multiple PubMed search modes. Out of these, n = 29 publications met the inclusion criteria with data from prospective analyses on >10 unselected patients presenting with MC or DCM (dataset: MA01). Data retrieved simultaneously from both controls and MC/DCM patients were available from n = 8 from these publications (dataset: MA02). Results: In the dataset MA01 B19V genomes were detected in 42.6% of the endomyocardial biopsies (EMB) in this cohort by PCR. In the dataset MA02 comprising n = 638 subjects, there was no statistically significant different rate of B19V positivity in myocardial tissues comparing controls (mean: 38.8 + 24.1%) versus the MC/DCM-patients (45.5 + 24.3%; p = 0.58). There was also no statistical difference between the positivity rate of B19V genomes in myocardial tissues of MA01 (46.0 + 19.5%) and the two patient groups of MA02 (p > 0.05). Conclusions: This systematic review reveals that the mean rate of PCR detected B19V genomes in patients presenting with MC/DCM does not differ significantly from the findings in control myocardial tissues. These data imply pathogenetically insignificant latency of B19V genomes in a proportion of myocardial tissues, both in MC-/DCM-patients and in controls. More information (i.e., replicative status, viral protein expression) is pertinent to achieve a comprehensive workup of myocardial B19V infection.

Cardiac Arrest in the Pediatric Cardiac ICU: Is Medical Congenital Heart Disease a Predictor of Survival?

OBJECTIVES

Children with medical cardiac disease experience poorer survival to hospital discharge after cardiopulmonary arrest compared with children with surgical cardiac disease. Limited literature exists describing epidemiology and factors associated with mortality in this heterogeneous population. We aim to evaluate the clinical characteristics and outcomes after cardiopulmonary arrest in medical cardiac patients.

DESIGN

We performed a retrospective review of pediatric cardiac patients who underwent cardiopulmonary resuscitation in a tertiary care cardiac ICU. Surgical cardiac patients underwent cardiac surgery immediately prior to ICU admission. Nonsurgical cardiac patients were divided into two groups based on the presence of congenital heart disease: congenital heart disease medical or noncongenital heart disease medical. Clinical and outcome variables were collected. Primary outcome was survival to hospital discharge.

SETTINGS

Texas Children's Hospital cardiac ICU.

PATIENTS

Patients admitted to Texas Children's Hospital cardiac ICU between January 2011 and December 2016.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of 150 cardiopulmonary arrest events reviewed, 90 index events were included (46 surgical, 26 congenital heart disease medical, and 18 noncongenital heart disease medical). There was no difference in primary outcome among the three groups. The absence of an epinephrine infusion precardiopulmonary arrest was associated with increased odds of survival in the congenital heart disease medical group (p = 0.03). Noncongenital heart disease medical patients experienced pulseless ventricular tachycardia/ventricular fibrillation more frequently than congenital heart disease medical patients (p = 0.02). Congenital heart disease medical patients had trends toward longer cardiac arrest durations, higher prevalence of neurologic sequelae postcardiopulmonary arrest, and higher mortality when extracorporeal support at cardiopulmonary resuscitation was employed.

CONCLUSIONS

Although trends in first documented rhythm, neurologic sequelae, and inotropic support prior to cardiopulmonary arrest were noted between groups, no significant differences in survival after cardiac arrest were seen. Larger scale studies are needed to better describe factors associated with cardiopulmonary arrest as well as survival in heterogeneous medical cardiac populations.

Cardiac manifestations of inherited metabolic disease in children

Inborn errors of metabolism (IEM) are responsible for around 5% of all cases of cardiomyopathy (CM) and for 15% of non-idiopathic cases. Storage disorders such as Pompe disease (glycogen storage disease type II) typically cause hypertrophic CM, whereas the accumulation of toxic metabolites, as seen in the organic acidurias, is associated with dilated cardiomyopathy (DCM). Mixed pathology is also possible, particularly in late presentations. IEM such as Barth syndrome, a disorder of cardiolipin stability usually associated with DCM, have been associated with rarer types of CM such as endocardial fibroelastosis and left ventricular non-compaction. Conduction disturbances can also occur, particularly in disorders of glycogen metabolism associated with PRKAG2 mutations. Cardiac screening of patients with metabolic diseases is important to guide treatment and stratify risk. Supportive cardiac treatment may be required, and although associated myocardial disease may improve or even resolve with correction of the underlying metabolic disturbance, progression to cardiac transplantation has been described. In this article we document all IEM known to be associated with cardiac disease in children, focusing on common and clinically important diagnoses. We also discuss the pathophysiology of the various types of CM, and present a recommended approach to screening in the pediatric population.

MicroRNA-98 plays a critical role in experimental myocarditis

BACKGROUND AND AIMS

Myocarditis is inflammation in the heart; its pathogenesis is to be further investigated. Activities of micro RNAs (miR) are associated with immune inflammation. This study tests a hypothesis that miR-98 is involved in the development of myocarditis.

METHODS

BALB/c mice were immunized with cardiac α-myosin heavy chain peptides (MyHC-α) to induce myocarditis. The effects of miR-98 on regulation of interleukin (IL)-10 were assessed by real time RT-PCR.

RESULTS

Mice immunized with MyHC-α showed myocarditis and lower frequency of IL-10⁺ B cells (B10 cell) in the hearts. Expression of miR-98 was higher, IL-10 was lower, in B cells isolated from the mouse hearts with myocarditis, which was negatively correlated with each other. Exposure to tumor necrosis factor-α up regulated miR-98 expression in B cells. Over-expression of miR-98 suppressed IL-10 expression in B cells. Blocking miR-98 or adoptively transplanting B10 cells attenuated experimental myocarditis.

CONCLUSIONS

miR-98 suppresses IL-10 expression in B cells in the heart, which plays an important role in myocarditis. MiR-98 may be a therapeutic target in the treatment of myocarditis.

Myocarditis in Paediatric Patients: Unveiling the Progression to Dilated Cardiomyopathy and Heart Failure

Myocarditis is a challenging and potentially life-threatening disease associated with high morbidity in some paediatric patients, due to its ability to present as an acute and fulminant disease and to ultimately progress to dilated cardiomyopathy. It has been described as an inflammatory disease of the myocardium caused by diverse aetiologies. Viral infection is the most frequent cause of myocarditis in developed countries, but bacterial and protozoal infections or drug hypersensitivity may also be causative agents. The prompt diagnosis in paediatric patients is difficult, as the spectrum of clinical manifestation can range from no myocardial dysfunction to sudden cardiac death. Recent studies on myocarditis pathogenesis have revealed a triphasic nature of this disease, which influences the diagnostic and therapeutic strategies to adopt in each patient. Endomyocardial biopsy remains the gold standard for diagnosing myocarditis, and several non-invasive diagnostic tools can be used to support the diagnosis. Intravenous immunoglobulin has become part of routine practice in the treatment of myocarditis in paediatric patients at many centres, but its true effect on the cardiac function has been the target of many studies. The aim of this review is to approach the recently discovered facets of paediatric myocarditis regarding its progression to dilated cardiomyopathy.

Relevance of cardiac parvovirus B19 in myocarditis and dilated cardiomyopathy: review of the literature

Over the last decade, parvovirus B19 (B19V) has frequently been linked to the pathogenesis of myocarditis (MC) and its progression towards dilated cardiomyopathy (DCM). The exact role of the presence of B19V and its load remains controversial, as this virus is also found in the heart of healthy subjects. Moreover, the prognostic relevance of B19V prevalence in endomyocardial biopsies still remains unclear. As a result, it is unclear whether the presence of B19V should be treated. This review provides an overview of recent literature investigating the presence of B19V and its pathophysiological relevance in MC and DCM, as well as in normal hearts. In brief, no difference in B19V prevalence is observed between MC/DCM and healthy control hearts. Therefore, the question remains open whether and how cardiac B19V may be of pathogenetic importance. Findings suggest that B19V is aetiologically relevant either in the presence of other cardiotropic viruses, or when B19V load is high and/or actively replicating, which both may maintain myocardial (low-grade) inflammation. Therefore, future studies should focus on the prognostic relevance of the viral load, replicative status and virus co-infections. In addition, the immunogenetic background of MC/DCM patients that makes them susceptible to develop heart failure upon presence of B19V should be more thoroughly investigated.

Parvovirus B19 myocarditis in children: an observational study

BACKGROUND

The advent of PCR testing for the presence of viral genomes has led to the identification of parvovirus B19 (PVB19) as a causative agent of myocarditis.

METHODS

The clinical presentation, course and outcome of children with PVB19 myocarditis was ascertained through a retrospective review. The PVB19 viral genome was detected by PCR from whole blood or endomyocardial biopsy specimens in patients presenting with new onset heart failure.

RESULTS

Seventeen patients presented at a median age of 1.3 years (range: 0.4-15.4 years) in cardiac failure with a mean fractional shortening of 15±3%. Eleven patients required mechanical ventilation and intravenous inotropes and seven required extra-corporeal mechanical oxygenation. Four of the five deaths occurred in patients who had a short prodromal illness of less than 48 hours. All patients with ST segment elevation died (n=4). All non-fulminant cases survived. Event-free survival occurred in 11/17 (65%) patients. Five (29%) patients died and one patient underwent heart transplantation. Complete recovery of cardiac function occurred within a median of 12 months (range: 1-48) in five patients. There was incomplete recovery in five patients and one patient had persistent dilated cardiomyopathy.

CONCLUSIONS

PVB19 can cause a devastating myocarditis in children. Children with fulminant myocarditis, ST segment changes or a short prodrome have the worst outcome. Transplantation may be considered, but is rarely required in the acute period if mechanical circulatory support is utilised. If the initial presentation is survived, recovery of the myocardium can occur even in those who had fulminant myocarditis.

Plasma microRNA profiling of children with idiopathic dilated cardiomyopathy

CONTEXT

Dilated cardiomyopathy (DCM) is the most common cardiomyopathy in children. MicroRNAs (miRNA) are small RNAs which have regulatory functions in many biological processes.

OBJECTIVE

We aimed to determine miRNA expression levels in plasma of children with DCM.

MATERIALS AND METHODS

Plasma expression levels of 379 miRNAs were compared between 23 DCM and 26 healthy children.

RESULTS

The expression levels of miR-618, miR-875-3p, miR-205, miR-194, miR-302a, miR-147, and miR-544 were found decreased. The expression levels of miR-518f and miR-454 were found increased in DCM patients.

DISCUSSION

miRNA level differences may provide the chance of using these miRNAs as new biomarkers.

Management of children with dilated cardiomyopathy in The Netherlands: Implications of a low early transplantation rate

BACKGROUND

The policy for listing and transplant for children with dilated cardiomyopathy (DCM) in The Netherlands has been conservative because of low donor availability. The effects of this policy on outcome are reported.

METHODS

This was a multicenter, nationwide study performed in 148 children with DCM. The primary outcome was death or heart transplant.

RESULTS

Overall, 43 patients (29%) died or were transplanted. Within 1 year of diagnosis, 21 patients died, and only 4 underwent transplantation (3 on mechanical circulatory support). The 1-year survival was 85% (95% confidence interval [CI] = 79-91), and 5-year survival was 84% (95% CI = 78-90). Transplantation-free survival at 1 year was 82% (95% CI = 75-88) and at 5 years was 72% (95% CI = 64-80). Within 1 year of diagnosis, with death as the main end-point (21 of 25, 84%), intensive care unit admission (hazard ratio = 2.6, p = 0.05) and mechanical circulatory support (hazard ratio = 3.2, p = 0.03) were risk factors (multivariable Cox analysis); inotropic support was longer in patients reaching an end-point. At >1 year after diagnosis, with transplantation as the main end-point (15 of 18, 83%), age >6 years (hazard ratio = 6.1, p = 0.02) was a risk factor. There were 56 (38%) children who recovered, 50% within 1 year of diagnosis. Recovery was associated with younger age; was similar in patients with myocarditis (43%) and idiopathic disease (41%); and was similar in patients initially admitted to the intensive care unit, admitted to the ward, or treated as outpatients.

CONCLUSIONS

The transplantation rate in our cohort in the first year was low, with 1-year and 5-year survival rates similar to other cohorts. Our results suggest that a conservative approach to list children for transplantation early after presentation may be justifiable except for patients with prolonged intensive care unit or mechanical circulatory support.

Evaluation of the diagnostic work-up in children with myocarditis and idiopathic dilated cardiomyopathy

The underlying etiology of dilated cardiomyopathy (DCM) in children varies, 14-22% is secondary to myocarditis, and the majority remains idiopathic. Etiology has prognostic value; however, 'a clinical diagnosis of myocarditis' has been frequently used because the gold standard [endomyocardial biopsy (EMB)] is often not performed. Therefore, a consistent diagnostic approach and interpretation is needed. In this multicenter study, we evaluated the diagnostic approach and interpretation of the viral results in children with myocarditis and idiopathic DCM. We included 150 children with DCM, of whom 103 were assigned the diagnosis myocarditis (n = 21) or idiopathic DCM (n = 82) by the attending physician. Viral tests were performed in 97/103 patients, in only 34% (n = 35) some of the tests were positive. Of those patients, we evaluated the probability of the assigned diagnosis using the viral test results. We classified viral test results as reflecting definite or probable myocarditis in 14 children and possible or unlikely myocarditis in 21 children. Based on this classification, 23% of patients were misclassified. We found that in children with DCM, the diagnostic approach varied and the interpretation was mainly based on viral results. Since a 'clinical diagnosis of myocarditis' has been frequently used in daily practice because of the lack of EMB results, a uniform protocol is needed. We propose to use viral test results in several steps (blood PCR, serology, PCR and/or cultures of the gastro-intestinal and respiratory tract, and EMB results) to estimate the probability of myocarditis.