Infantile dilated cardiomyopathy. Relation of outcome to left ventricular mechanics, hemodynamics, and histology at the time of presentation

Paediatric dilated cardiomyopathy with and without endocardial fibroelastosis - a pathological analysis of 89 explants

Heart failure due to dilated cardiomyopathy is a major indication for paediatric cardiac transplantation. Endocardial fibroelastosis is a recognised pathological finding of unknown prognostic significance in paediatric dilated cardiomyopathy. To evaluate the nature of the association between left ventricular endocardial fibroelastosis and paediatric dilated cardiomyopathy, we reviewed surgical pathology reports of dilated cardiomyopathy explants (1986-2016) in order to characterise the pathological findings and to compare and contrast their frequency among four age groups: less than 1 year; 1-5 years; 6-10 years; and greater than 11 years. The 89 explants (47 males and 42 females) were all characterised by increased weight and left ventricular chamber dilatation without increased wall thickness. Ninety-five per cent of the specimens in the two youngest subsets had left ventricular endocardial fibroelastosis. Compared to the oldest age group, recipients aged 1-5 years had a 6-fold increase and those younger than 1 year a 19-fold increase in the odds of observing left ventricular endocardial fibroelastosis. Explants with and without endocardial fibroelastosis were otherwise phenotypically similar. In paediatric dilated cardiomyopathy endocardial fibroelastosis is a very common pathological finding, especially in infants and young children. We propose that the descriptive, clinico-pathological designation "Dilated Cardiomyopathy with Endocardial Fibroelastosis" should be adopted to facilitate future investigation into the potential prognostic/therapeutic significance of left ventricular endocardial fibroelastosis.

Clinical Profile and Risk Factors for Cardiac Death in Pediatric Patients With Primary Dilated Cardiomyopathy at a Tertiary Medical Center in China

AIM

We sought to identify the clinical characteristics and risk factors for cardiac mortality in pediatric patients with primary dilated cardiomyopathy (DCM) in China.

METHODS

A total of 138 pediatric patients who were consecutively diagnosed with primary DCM from January 2011 to December 2020 were included. We assessed patients' clinical symptoms and performed laboratory examinations, electrocardiography, and echocardiography.

RESULTS

Of these patients, 79 (57%) had severe systolic dysfunction (left ventricular ejection fraction of < 30%), 79 (57.2%) developed DCM before 12 months of age, 62 (45%) were male, 121 (87.7%) presented with advanced heart failure (cardiac functional class III/IV), and 54 (39.1%) presented with arrhythmia. At a median follow-up of 12 months, the overall cardiac mortality rate was 33%, and 40 of 46 deaths occurred within 6 months following DCM diagnosis. A multivariate Cox regression analysis identified several independent cardiac death predictors, including an age of 12 months to 5 years [hazard ratio (HR) 2.799; 95% confidence interval (CI) 1.160-6.758; P = 0.022] or 10-15 years (HR 3.617; 95% CI 1.336-9.788; P = 0.011) at diagnosis, an elevated serum alanine aminotransferase (ALT) concentration (≥ 51.5 U/L) (HR 2.219; 95% CI 1.06-4.574; P = 0.031), and use of mechanical ventilation (HR 4.223; 95% CI 1.763-10.114; P = 0.001).

CONCLUSION

The mortality rate of primary DCM without transplantation is high. Age, an elevated serum ALT concentration, and the need for mechanical ventilation predict mortality in patients with primary DCM, providing new insights into DCM risk stratification.

An Overview of Neonatal Lupus with Anti-Ro Characteristics

Neonatal lupus erythematosus (NLE) is a syndrome of clinical symptoms observed in neonates born to mothers with antibodies to soluble antigens of the cell nucleus. The main factors contributing to the pathogenesis of this disease are anti-Sjögren Syndrome A (anti-SS-A) antibodies, known as anti-Ro, and anti-Sjögren Syndrome B (anti-SS-B) antibodies, known as anti-La. Recent publications have also shown the significant role of anti-ribonucleoprotein antibodies (anti-RNP). Seropositive mothers may have a diagnosed rheumatic disease or they can be asymptomatic without diagnosis at the time of childbirth. These antibodies, after crossing the placenta, may trigger a cascade of inflammatory reactions. The symptoms of NLE can be divided into reversible symptoms, which concern skin, hematological, and hepatological changes, but 2% of children develop irreversible symptoms, which include disturbances of the cardiac stimulatory and conduction system. Preconceptive care and pharmacological prophylaxis of NLE in the case of mothers from the risk group are important, as well as the monitoring of the clinical condition of the mother and fetus throughout pregnancy and the neonatal period. The aim of this manuscript is to summarize the previous literature and current state of knowledge about neonatal lupus and to discuss the role of anti-Ro in the inflammatory process.

Development of Cardiac Events and Functional Recovery Prediction Models for Pediatric Dilated Cardiomyopathy

Background: Since both the risk of death and the probability of spontaneous functional recovery (FR) coexist in association with pediatric dilated cardiomyopathy (DCMP), management should be based on individualized outcome predictions. Methods: A single-center retrospective review of 105 pediatric patients (age at presentation ≤ 18 years) with DCMP, managed between 1994 and 2017, was performed. Logistic regression was conducted to identify variables associated with FR and cardiac events (CEs), i.e., death or heart transplantation (HTPL), within 2 years after initial presentation. Two outcome prediction models were formulated using these variables. Results: Twenty-six (24.8%) and 51 patients (48.6%) experienced FR and CE, respectively, within 2 years after initial presentation. Predictors of mortality without HTPL were earlier era at presentation (HR: 4.13; 95% CI: 1.88-9.06; p < 0.001) and significant TR (≥moderate; HR: 4.31; 95% CI: 1.26-14.77; p = 0.020) in multivariable Cox regression model. Predictors of FR were recent era (HR: 4.49; 95% CI: 1.40-14.44; p = 0.0012), younger age at initial presentation (HR: 0.98 per 1 month increase; 95% CI: 0.97-0.99, p < 0.001), post-myocarditis DCMP (HR: 4.29; 95% CI: 1.32-13.93; p = 0.015), and arrhythmia-mediated DCMP (HR: 26.88; 95% CI: 2.61-276.70; p = 0.006). Risk factors for CEs was idiopathic DCMP (HR: 2.95; 95% CI: 1.32-6.56, p = 0.008). The low-risk group who had higher probability of FR than CE in prediction model had a slightly higher overall survival rate (71.4 vs. 52.2% at 10 years after presentation; log-rank p = 0.09) and a significantly higher HTPL-free survival rate (67.5 vs. 24.9% at 10 years after presentation; log-rank p < 0.001) than the high-risk group. Conclusions: Prognostication and management strategies for pediatric DCMP may be enhanced by risk stratification using outcome prediction modeling.

Left Atrial Strain to Identify Diastolic Dysfunction in Children with Cardiomyopathies

Background: Left ventricular (LV) diastolic dysfunction (DD) carries worse prognosis in childhood. 2-dimensional (2-D) left atrial (LA) strain accurately categorizes DD in adults but its role in children is unknown. Thus, the aim of this study is to investigate whether LA strain and strain rate could diagnose and classify DD in children with dilated (CMD), hypertrophic (HCM) and restrictive (RCM) cardiomyopathies (CM). Methods and Results: The study includes 136 children (aged 8.8 ± 6 years): 44 with DCM, 40 with HCM, 7 with RCM and 45 healthy controls (CTRL). They underwent standard echocardiographic examination and 2-D speckle-tracking analyses (LV longitudinal peak systolic strain (LS), LA peak systolic strain and strain rate). No significant differences in mitral E/A and pulmonary S/D ratios were observed among the four groups. Although E/E’ and indexed left atrial volumes were found to be significantly higher in HCM, DCM and RCM compared to CTRL (p < 0.001), they showed no significant difference among the three CM groups. LV LS values were significantly reduced in CM vs CTRL (p < 0.001) and in DCM vs HCM (p < 0.01), with no other differences between the remaining groups. LA peak systolic strain and strain rate values showed a steady and significant decrease with worsening of DD. Receiver Operating Characteristics (ROC) curves showed area under the curve of 0.976 (p < 0.001) for LA strain and 0.946 (p < 0.001) for LA strain rate, to distinguish CTRL from CMs. Conclusions: LA strain and strain rate could be a promising tool to better understand and classify DD in children with cardiomyopathies, opening the way to its clinical use.

Analysis of clinical parameters and echocardiography as predictors of fatal pediatric myocarditis

Pediatric myocarditis symptoms can be mild or as extreme as sudden cardiac arrest. Early identification of the severity of illness and timely provision of critical care is helpful; however, the risk factors associated with mortality remain unclear and controversial. We undertook a retrospective review of the medical records of pediatric patients with myocarditis in a tertiary care referral hospital for over 12 years to identify the predictive factors of mortality. Demographics, presentation, laboratory test results, echocardiography findings, and treatment outcomes were obtained. Regression analyses revealed the clinical parameters for predicting mortality. During the 12-year period, 94 patients with myocarditis were included. Of these, 16 (17%) patients died, with 12 succumbing in the first 72 hours after admission. Fatal cases more commonly presented with arrhythmia, hypotension, acidosis, gastrointestinal symptoms, decreased left ventricular ejection fraction, and elevated isoenzyme of creatine kinase and troponin I levels than nonfatal cases. In multivariate analysis, troponin I > 45 ng/mL and left ventricular ejection fraction < 42% were significantly associated with mortality. Pediatric myocarditis had a high mortality rate, much of which was concentrated in the first 72 hours after hospitalization. Children with very high troponin levels or reduced ejection fraction in the first 24 hours were at higher risk of mortality, and targeting these individuals for more intensive therapies may be warranted.

Neutrophil-to-lymphocyte ratio used as prognostic factor marker for dilated cardiomyopathy in childhood and adolescence

Objective

The objective of this study is to evaluate the neutrophil-to-lymphocyte ratio (NLR) and platelet-lymphocyte ratio, from the hemograms obtained from children and adolescents with dilated cardiomyopathy (DCM), and to correlate them with the levels of B-type natriuretic peptide (BNP) and with the clinical evolution of these patients in the long term.

Materials and Methods

Follow-up of 57 patients with DCM was made retrospectively, with hemogram and BNP level determination being performed after optimized therapy for heart failure. We compared the findings of the patients' examinations that progressed with stability in relation to the occurrence of transplant listing, cardiac transplantation, or evolution to death.

Results

The average age was 48 months, and the follow-up was 64 months. The average of the levels of neutrophils was greater in poor evolution group (7026 vs. 3903; P = 0.011) as well as the average of NLR (5.5 vs. 1.9; P = 0.034). The averages of hemoglobin, total leukocytes, lymphocytes, and platelets were similar in the groups. The area under the receiver operating characteristic curve for NLR in relation to the poor evolution was of 72.9%, being the best cutoff point of NLR ≥5.2 (sensitivity: 93.8% and specificity: 87.8%). Kaplan-Meier curves demonstrate that patients with NLR ≤5.2 (P = 0.001) and BNP <1000 pg/dl (P < 0.0001) presented greater survival.

Conclusions

NLR (≥5.2) and lymphopenia (≤1000 lymphocyte/μL) were associated with a poor prognosis and a higher chance of evolution to death or cardiac transplant, similar to the findings for BNP.

Norwood Stage 1 With Surgical Ventricular Reconstruction and Mitral Valve Repair for Neonatal Idiopathic Left Ventricular Dilated Cardiomyopathy

A newborn girl presented with a prenatal diagnosis of dilated left ventricular cardiomyopathy, mitral valve regurgitation, and ductal-dependent circulation. The left ventricle was severely dilated and hypokinetic. The patient underwent Norwood stage 1 single ventricle palliation with a Damus-Kaye-Stansel anastomosis, atrioseptectomy, and a modified Blalock-Taussig shunt. The left ventricle was managed with Batista surgical ventricular reconstruction, with resection of the dilated and thinned ventricular myocardium, along with periventricular Alfieri repair of the mitral valve. The patient had an uneventful postoperative recovery, followed by stage 2 bidirectional Glenn and tricuspid valvuloplasty at 2.75 months of age.

Immunosuppressive therapy in myocarditis

Although there is general agreement on the favorable effect of immunosuppression in eosinophilic, granulomatous, giant-cell myocarditis and in lymphocytic myocarditis associated with connective tissue disorders and with rejection of a transplanted heart, its therapeutic role in lymphocytic inflammatory cardiomyopathy (ICM) is still debated. Previous retrospective studies reported a relevant clinical benefit in 90% of patients with virus-negative ICM and no response or cardiac impairment in 85% of those with virus-positive ICM following immunosuppression. Other studies identified cardiomyocyte HLA upregulation as an additional indicator of ICM susceptibility to immunosuppressive therapy. Recently in a single-center randomized prospective double-blind trial using a combination of prednisone and azathioprine in addition to supportive treatment in 85 virus-negative ICM patients, a significant improvement in left ventricular (LV) ejection fraction and a significant reduction in LV dimensions in 88% of 43 treated patients compared with 42 patients receiving placebo who showed a cardiac impairment in 83% of cases (TIMIC study) was reported. These data confirm the efficacy of immunosuppression in virus-negative ICM. Lack of response in 12% of cases suggests the presence of unscreened viruses or mechanisms of damage and inflammation not susceptible to immunosuppression. Recovery of cardiac function in responders to immunosuppression was associated with inhibition of cardiomyocyte death, increased cell proliferation and with newly synthesized contractile material.

Genetics of inherited cardiomyopathies

Cardiomyopathies are the most common disorders resulting in heart failure, with dilated cardiomyopathy being responsible for the majority of cases. Other forms of cardiomyopathy, especially hypertrophic forms, are also important causes of heart failure. The mortality rate due to cardiomyopathy in the USA is over 10,000 deaths per year, and the costs associated with heart failure are approximately 200 million US dollars per year in the USA alone. Over the past few years, breakthroughs have occurred in understanding the basic mechanisms of these disorders, potentially enabling clinicians to devise improved diagnostic strategies and therapies. As at least 30 to 40% of cases are inherited, it is now imperative that the genetic basis for these disorders is clearly recognized by caregivers and scientists. However, it has also become clear that these diseases are genetically highly heterogeneous, with multiple genes identified for each of the major forms of cardiomyopathy, and most patients having private mutations. These data suggest that the genetic diagnosis of most patients with cardiomyopathy will be impractical with current technologies. However, there are a few exceptions, such as patients with X-linked cardiomyopathies, with or without the concomitant abnormalities of cyclic neutropenia and 3-methylglutaconic aciduria, or patients with cardiomyopathy associated with conduction disease: these appear to be associated with mutations in a small subset of genes, and can be investigated by certified diagnostic laboratories. This review will summarize current knowledge of the genetics of inherited cardiomyopathies and how findings from research laboratories may be translated into the diagnostic laboratory.

Echocardiographic methods, quality review, and measurement accuracy in a randomized multicenter clinical trial of Marfan syndrome

BACKGROUND

The Pediatric Heart Network is conducting a large international randomized trial to compare aortic root growth and other cardiovascular outcomes in 608 subjects with Marfan syndrome randomized to receive atenolol or losartan for 3 years. The authors report here the echocardiographic methods and baseline echocardiographic characteristics of the randomized subjects, describe the interobserver agreement of aortic measurements, and identify factors influencing agreement.

METHODS

Individuals aged 6 months to 25 years who met the original Ghent criteria and had body surface area-adjusted maximum aortic root diameter (ROOTmax) Z scores > 3 were eligible for inclusion. The primary outcome measure for the trial is the change over time in ROOTmaxZ score. A detailed echocardiographic protocol was established and implemented across 22 centers, with an extensive training and quality review process.

RESULTS

Interobserver agreement for the aortic measurements was excellent, with intraclass correlation coefficients ranging from 0.921 to 0.989. Lower interobserver percentage error in ROOTmax measurements was independently associated (model R(2) = 0.15) with better image quality (P = .002) and later study reading date (P < .001). Echocardiographic characteristics of the randomized subjects did not differ by treatment arm. Subjects with ROOTmaxZ scores ≥ 4.5 (36%) were more likely to have mitral valve prolapse and dilation of the main pulmonary artery and left ventricle, but there were no differences in aortic regurgitation, aortic stiffness indices, mitral regurgitation, or left ventricular function compared with subjects with ROOTmaxZ scores < 4.5.

CONCLUSIONS

The echocardiographic methodology, training, and quality review process resulted in a robust evaluation of aortic root dimensions, with excellent reproducibility.

The effect of carvedilol treatment on chronic heart failure in pediatric patients with dilated cardiomyopathy: a prospective, randomized-controlled study

This study aimed to evaluate the clinical efficacy and safety of carvedilol for pediatric patients with chronic heart failure caused by dilated cardiomyopathy. Seven pediatric medical centers participated in this prospective study. Pediatric patients (n = 89) were randomly divided into an experimental group (carvedilol treatment) and a control group (conventional treatment). The analysis excluded 12 patients lost during the follow-up period. Carvedilol was added to the therapy of the experimental group after at least 1 month of basic treatment with digoxin, an angiotensin-converting-enzyme inhibitor, and diuretics. The control patients received the same basic treatment but did not receive carvedilol. The initial dose of carvedilol was 0.1 (mg/kg day), and the dose was doubled every 2 weeks until the maximum tolerated dose or 0.8 (mg/kg day) was achieved. The tolerated dose was maintained for 6 months. The Ross scales and echocardiographic parameters including left ventricular diastolic diameter, left ventricular systolic diameter, left ventricular ejection fraction, left ventricular fractional shortening, and serous brain natriuretic peptide (BNP) concentration, as well as clinical progress were compared between the two groups. The Ross scales decreased by 11.94% in the experimental group, which was more than in the control group (2.81%). In addition, changes to other echocardiographic parameters in the experimental group also were superior to those in the control group. The serous BNP concentration in the experimental group decreased by 30.1%, which also was more than the decrease (22.2%) observed in the control group. Clinical improvement was demonstrated by 40%, no change by 35%, and clinical deterioration by 25% of the patients in the experimental group, and by respectively 37.8, 27, and 35.2% of the patients in the control group. These differences were not statistically significant. Only one patient demonstrated a severe adverse event, severe pulmonary infection, and complete atrioventricular block. None of the other carvedilol-treated patients experienced drug-related side effects. Carvedilol can be safely used for treatment of chronic heart dysfunction in pediatric patients with dilated cardiomyopathy. The results in this study showed an apparent improvement in the cardiac function of these patients. Additional clinical studies are required to determine the most favorable dosing levels and regimens of carvedilol before its safety and efficacy for the pediatric population can be determined conclusively.

The ventricular volume variability study of the Pediatric Heart Network: study design and impact of beat averaging and variable type on the reproducibility of echocardiographic measurements in children with chronic dilated cardiomyopathy

BACKGROUND

Clinical trials often rely on echocardiographic measures of left ventricular size and function as surrogate end points. However, the quantitative impact of factors that affect the reproducibility of these measures is unknown. To address this issue, the National Heart, Lung, and Blood Institute-funded Pediatric Heart Network designed a longitudinal observational study of children with known or suspected dilated cardiomyopathy aged 0 to 22 years from eight pediatric clinical centers.

METHODS

Clinical data were collected together with 150 echocardiographic indices of left ventricular size and function. Separate observers performed duplicate echocardiographic imaging. Multiple observers performed measurements from three cardiac cycles to enable assessment of intraobserver and interobserver variability. The impacts of beat averaging (BA), observer type (local vs core), and variable type (areas, calculations, dimensions, slopes, time intervals, and velocities) on measurement reproducibility were studied. The outcome measure was percentage error (100 × difference/mean).

RESULTS

Of 173 enrolled subjects, 131 met criteria for dilated cardiomyopathy. BA, variable type and observer type all influenced percentage error (P < .0001). Core interobserver percentage error (medians, 11.4%, 10.2%, and 9.3% for BA using one, two, and three beats, respectively) was approximately twice the intraobserver percentage error (medians, 6.3%, 4.9%, and 4.2% for BA using one, two, and three beats, respectively). Slopes and calculated variables exhibited high percentage error despite BA. Chamber dimensions, areas, velocities, and time intervals exhibited low percentage error.

CONCLUSIONS

This comprehensive evaluation of quantitative echocardiographic methods will provide a valuable resource for the design of future pediatric studies. BA and a single core lab observer improve the reproducibility of echocardiographic measurements in children with dilated cardiomyopathy. Certain measurements are highly reproducible, while others, despite BA, are poorly reproducible.

Anaemia is a predictor of early death or cardiac transplantation in children with idiopathic dilated cardiomyopathy

INTRODUCTION

The aim of our study was to establish the prevalence and the prognostic value of haematological abnormalities in children with cardiac failure.

PATIENTS AND METHODS

A series of 218 consecutive children with a first diagnosis of idiopathic dilated cardiomyopathy were retrospectively examined. Haematological evaluation was performed at first diagnosis. Death or cardiac transplantation was the main outcome measure.

RESULTS

The median age was 0.6 years, ranging from 1 day to 15.8 years and median follow-up was 2.65 years, ranging from 0 to 17.2 years. After a median interval of 0.2 years, ranging from 0 to 8.7 years, 56 patients died and 25 were transplanted. Event-free survival at 1 and 5 years was 68% (95% confidence interval, 63-75%) and 62% (95% confidence interval, 56-69%). Blood levels of haemoglobin less than 10 grams per decilitre, urea over 8 millimoles per litre, and C-reactive protein over 10 milligrams per litre were found in 24%, 20%, and 24% of patients, respectively. The log-rank test showed that haemoglobin (p = 0.000) and C-reactive protein (p = 0.021) were predictors of death or transplantation. In the multivariate Cox model, haemoglobin (hazard ratio = 0.735; confidence interval = 0.636-0.849; p = 0.000) and urea (hazard ratio = 1.083; confidence interval = 1:002-1:171; p = 0.045) were predictive of poor outcome. Cubic spline functions showed that the positive role of haemoglobin on survival was linear for values less than 12 grams per decilitre and null for values more than 12 grams per decilitre. Adaptive index models for risk stratification and Classification and Regression Tree analysis allowed to identify the cut-off values for haemoglobin (less than 10.2 grams per decilitre) and urea (more than 8.8 millimoles per litre), as well as to derive a predictor model.

CONCLUSIONS

In children with idiopathic dilated cardiomyopathy, anaemia is the strongest independent prognostic factor of early death or transplantation.

Intramyocardial administration of autologous bone marrow mononuclear cells in a critically ill child with dilated cardiomyopathy

Almost half of the children with symptomatic dilated cardiomyopathy receive a transplant or die within 2 years; however, cardiac stem cell transplantation has become a promising therapeutic option. The present case demonstrates for the first time, to our knowledge, the intramyocardial administration of autologous bone marrow mononuclear cells in a critically ill 4-month-old child with severe dilated cardiomyopathy. Left ventricular ejection fraction increased from 20% before stem cell transplantation to 41% at 4 months of follow-up.

Special report: Nursing diagnoses and interventions for a child with dilated cardiomyopathy requiring intra-aortic balloon pump support--case report

OBJECTIVE

The study aims to identify the nursing diagnoses and interventions for a child requiring intra-aortic balloon pump support.

METHODS

This was a case study of a 7-year-old child. The nursing diagnoses and interventions were obtained by three cardiology and pediatric specialist nurses, familiar with NANDA-International and Nursing Intervention Classification taxonomies.

RESULTS

Many nursing diagnoses and interventions were identified, but the main diagnosis for this patient was decreased cardiac output.

CONCLUSIONS

The nursing care for a child with an intra-aortic balloon requires well-qualified professionals, prepared to handle the diagnoses and interventions identified in this study.

PRACTICAL IMPLICATIONS

The use of a standard language system is essential to guide professionals in the caring process, providing essential elements to optimize interpretations.

A new presentation of neonatal lupus: 5 cases of isolated mild endocardial fibroelastosis associated with maternal Anti-SSA/Ro and Anti-SSB/La antibodies

OBJECTIVE

Maternal anti-SSA/Ro or anti-SSB/La antibodies are associated with neonatal lupus erythematosus syndrome (NLES), especially congenital heart block (CHB), which may be associated with severe endocardial fibroelastosis (EFE) and dilated cardiomyopathy (DCM). A few reports have described severe EFE without CHB associated with anti-SSA/Ro antibodies, with a poor prognosis. EFE has also been observed in biopsies of DCM that had been considered idiopathic. These points, considered in association with 5 unusual cases of mild EFE, led us to consider the relationship between underrecognized cases of isolated autoantibody-associated EFE and DCM that had been considered idiopathic.

METHODS

We analyzed 5 cases of EFE diagnosed in utero (n = 4) or after birth (n = 1). In 3 cases, maternal antibody status was discovered because of the EFE diagnosis.

RESULTS

Endomyocardial hyperechogenicity predominated in the left atrium (n = 3) and mitral annulus (n = 3). No left-heart dysfunction was observed. Two mothers were treated with betamethasone. One mother chose to have a therapeutic abortion, and EFE was confirmed at autopsy. Electrocardiograms at birth (n = 4) did not show CHB. Other manifestations of NLES were present in all cases. One child had right ventricular hypoplasia and underwent a partial cavopulmonary anastomosis. At last followup (4-7 yrs), the other 3 children had normal heart function, and echocardiography showed a normal heart (n = 2) or mild persistent EFE (n = 1).

CONCLUSION

Middle-term prognosis of isolated autoantibody-associated EFE may be better than previously reported, although the longterm prognosis remains unknown. We hypothesize that a fetal insult can lead to DCM.

Dilated cardiomyopathy in epidermolysis bullosa

Dilated cardiomyopathy (DC) is a rare but potentially fatal complication of epidermolysis bullosa. No clear cause for it has been identified, but iron overload, low carnitine, low selenium, concomitant viral illness, chronic anemia, and medications have been proposed as possible contributors to the development of DC in reported cases. Early detection allows for medical treatment that delays clinical progression and prolongs survival.

Dilated cardiomyopathy in epidermolysis bullosa: a retrospective, multicenter study

Dilated cardiomyopathy (DC) has been reported in severe epidermolysis bullosa (EB) subtypes. Poor nutritional status, low carnitine levels, selenium deficiency, chronic iron overload, drugs and viral etiology have been proposed as potential contributors. This was a retrospective, descriptive, multicenter study describing EB patients that developed DC, and determining potential pre-disposing risk factors. Fifteen patients were enrolled in the study; 11 of them were male subjects (73%). Eighty-seven per cent of the participants had dystrophic EB and 13% had junctional EB. Mean age at diagnosis of DC was 12.18 +/- 4.99 years. Chronic anemia was diagnosed in 13 of 15 patients (86.7%). Sixty per cent of patients had prior red blood cell transfusions. At diagnosis, selenium levels were low in 55% of the patients (n = 11) and total carnitine levels were low in 45% of the patients (n = 11). Systolic function was moderately impaired, with a mean shortening fraction of 19.38% (SD = 5.04, n = 8). After a mean follow-up period of 6.3 +/- 4.8 years, six patients were alive without being on any medications (40.0%), two were alive on medications (13.3%) and seven had died (46.7%). Limitations of the study was that it was a retrospective chart review with relatively small sample size. Retrospective chart review, relatively small sample size. This study substantiates the association between DC and EB. Currently, there is no single risk factor identified in EB patients that leads to DC. Further prospective studies are needed.

The impact of changing medical therapy on transplantation-free survival in pediatric dilated cardiomyopathy

OBJECTIVES

We sought to determine whether the introduction of these agents had altered the outcome of dilated cardiomyopathy (DC) in childhood.

BACKGROUND

Pediatric DC has a poor prognosis. Angiotensin-converting enzyme inhibitors (ACEIs) and beta-adrenergic receptor blockers (BBs) improve survival in adults with DC, but their effectiveness in children has not been confirmed.

METHODS

We performed a single-institution retrospective review of all diagnosed cases of DC and related phenotypic variants between 1976 and 2005, with multivariate analysis of risk factors for the end point of death or cardiac transplantation.

RESULTS

A total of 189 patients presented between January 1, 1976, and March 31, 2005. Forty-four patients died, 34 underwent cardiac transplantation, and 10 were lost to follow-up during this period. The 2- and 5-year transplantation-free survival rates for all patients were 63.6% (95% confidence interval [CI]: 56.4% to 70.8%) and 56.3% (95% CI: 48.5% to 64.1%), respectively. For patients treated with digoxin but neither an ACEI nor a BB (n = 51), the 5-year transplantation free survival rate was 67.5% (95% CI: 53.5% to 82.0%) and for those treated with the addition of an ACEI but no BB (n = 65), the rate was 57.2% (95% CI: 43.6% to 69.4%) (p = NS). Combination therapy with an ACEI and a BB (n = 57) was not associated with an improvement in 5-year transplantation-free survival (58.5%; 95% CI: 42.5% to 72.0%, p = NS). In multivariable analysis, presentation with a low left ventricular ejection fraction increased the risk of death or transplantation, but the end point was not influenced by time era or treatment strategy.

CONCLUSIONS

DC in childhood has a high risk of death or the need for transplantation. Medical treatment has shifted toward combination ACEI and BB therapy in the current era. Our retrospective data, however, suggest only a transient survival advantage associated with the combined use of ACEI and BB over ACEI alone and no obvious or sustained improvement in transplantation-free survival accompanying the change from digoxin-based medical therapy.

Implication of QRS prolongation and its relation to mechanical dyssynchrony in idiopathic dilated cardiomyopathy in childhood

We explored the role of QRS prolongation (>or=120 ms) and its relation to mechanical dyssynchrony and outcomes in childhood idiopathic dilated cardiomyopathy (IDC). A total of 89 patients <or=18 years old diagnosed as having IDC (21 days to 26 years of follow-up) were investigated. In 20 survivors with residual left ventricular (LV) dysfunction, mechanical (interventricular and intra-LV) dyssynchrony was assessed. The SD of time from the beginning of QRS prolongation to peak systolic contraction was measured in 12 LV segments by tissue Doppler imaging. A cut-off value >32.6 ms was used to define intra-LV dyssynchrony. The 1- and 5-year survivals were 70% and 53%, respectively. Requirement of intravenous inotropes at follow-up (hazard ratio 3.10) and initial LV ejection fraction (hazard ratio 0.95) were major prognostic factors. QRS prolongation, primarily left bundle branch block, was identified in 16 patients (18%) and tended to increase the risk of requiring inotropes. Moreover, none of those with QRS prolongation regained normal cardiac function at follow-up. Two patients with QRS prolongation showed marked improvement in cardiac function after cardiac resynchronization therapy. Mechanical dyssynchrony was noted in all patients with QRS prolongation and in 8% (interventricular) or 38% (intra-LV) of those without. In conclusion, QRS prolongation was common in childhood IDC and was possibly associated with persistent LV dysfunction and worse cardiac outcome. Mechanical (inter- and intraventricular) dyssynchrony was highly prevalent in those with QRS prolongation and was still often observed in those without.

Is myocardial performance index an independent echocardiographic marker of death in children with idiopathic dilated cardiomyopathy?

BACKGROUND

Myocardial performance index (MPI) was reported as a parameter of ventricular systolic and diastolic function, as well as a useful tool to predict the outcome in patients with ventricular dysfunction.

HYPOTHESIS

To compare MPI with classical echocardiographic parameters as an independent marker of death in children with idiopathic dilated cardiomyopathy (IDCM).

METHODS

Fifty-five children (13 deaths) underwent 104 echocardiograms from January 1996 to May 2005. Right ventricle (RV) MPI and left ventricle (LV) MPI, and 9 classical echocardiographic parameters (left atrium [LA]/body surface area [BSA], distance between mitral E point and ventricular septum, LV mass/body surface area, RV shortening fraction, LV end-systolic and end-diastolic dimensions/body surface area, LV ejection fraction, fiber circumferential shortening velocity, and mitral deceleration time) were compared. Statistical analysis was performed by chi-square, Pearson's correlation and Student t-test, Kaplan-Meier method, Cox's method, and receiver operating curve (ROC). Statistical significance was considered with alpha<0.05 and p=0.80].

RESULTS

Univariate analysis showed that all studied parameters were markers of death. There was a high correlation between RVMPI and LVMPI (r=0.847]-p=0.0001]); therefore, to avoid bias, RVMPI was discharged from multivariate analysis. In the deceased group, moderate/severe mitral regurgitation was frequent (76.9%; confidence interval [CI[ 95%=46.2%- 94.9%) and it was considered in multivariate analysis. In Cox's multivariate analysis, LVMPI was the only independent marker of death (p=0.0213]). The ideal cut-off was 0.63 with 92.3% sensitivity, 66.7% specificity, and fitted ROC area=0.918].

CONCLUSIONS

In children with IDCM, LVMPI is an independent marker of death.

Histology of the explanted hearts of children transplanted for dilated cardiomyopathy

There is little information as to the histology of the explanted hearts of children transplanted for presumed dilated cardiomyopathy. We therefore aimed to describe the histology of these explants. Thirty-six children [mean age 7.4 years (range 0.1-17)] transplanted for dilated cardiomyopathy were identified. Based on histological examination of the explanted hearts patients were classified into three groups: severe inflammation, mild to moderate inflammation, and minimal or no inflammation. Cell death/damage and fibrosis were also scored. Duration of symptoms and degree of support at transplant were ascertained from the case notes. Two patients had severe confluent inflammation, nine mild or moderate focal inflammation, and 25 minimal or no inflammation. The degree of inflammation and fibrosis did not correlate with the interval between presentation and transplant (p = 0.37 and p = 0.78). Patients requiring inotropes or ventricular assist had a shorter time interval between presentation and transplant (p = 0.017) although these levels of support were not associated with the degree of inflammation or fibrosis (p = 0.90 and 0.5). We conclude that the explanted hearts of one-third of children transplanted for presumed cardiomyopathy have some degree of inflammation. Histological findings are not associated with symptom duration or support required.

Outcome Predictors for Pediatric Dilated Cardiomyopathy: A Systematic Review

Dilated cardiomyopathy comprises the largest group of pediatric cardiomyopathy functional types and is the most common indication for heart transplant in children over 5 years old. Prognostic factors for this condition have long been sought by many researchers. In a systematic review of these factors, we found 32 relevant articles published since 1976. Four studies report finding no predictive factors. In the remaining 28 studies, several factors indicating better prognosis stand out across multiple articles: younger age at diagnosis, higher left-ventricular fractional shortening and ejection fraction, and the presence of myocarditis. Results for other factors conflict across studies: severe mitral regurgitation, arrhythmias, and a family history of cardiomyopathy. Elevated left-ventricular end diastolic pressure was statistically significant in two studies, but it may be of limited utility as a result of its invasiveness. Although most children have congestive heart failure at presentation, only two studies found it to be a significant predictor of mortality. The largest study of this factor qualified the increased risk to 1 year after presentation. Other significant predictors that have not been analyzed or reported by more than one study group, are right ventricular failure and impaired cardiac adrenergic innervation, as detected by radiolabeled meta-iodobenzylguanidine imaging. Although 1- and 5-year survival rates have steadily improved, as more children with DCM receive cardiac transplants, event-free survival rates (the absence of "heart death" resulting in death or transplant) are similar to those from decades ago. A unified risk algorithm may assist in clinical decision-making but requires more studies. Other studies are needed to assess the post-transplant survival experience.

Outcome factors of idiopathic dilated cardiomyopathy in children - a long-term follow-up review

BACKGROUND

Idiopathic dilated cardiomyopathy in children has a high rate of mortality. Cardiac transplantation is the treatment of choice in those who fail to respond to therapeutics. Several studies have been carried out to determine unfavourable prognoses, and to provide an early indication for cardiac transplantation. Nevertheless, no consensus has been reached on the matter.

OBJECTIVE

To propose predictors of death in children with idiopathic dilated cardiomyopathy.

METHODS

We reviewed data extending over 22 years from 142 consecutive children with idiopathic dilated cardiomyopathy, of whom 36 died. The criteria for inclusion were the presence of congestive heart failure or cardiomegaly in a routine chest X-ray, confirmed by enlargement and hypo kinesis of the left ventricle in the echocardiogram. We included asymptomatic children in functional class I. Based on Cox's analysis of clinical and laboratory data, we sought any predictors of death.

RESULTS

In univariate analysis, the predictors were functional class IV at presentation (p equal to 0.0001), dyspnoea (p equal to 0.0096), and reduced pedal pulses (p equal to 0.0413). In chest X-ray, they were maximal cardiothoracic ratio (p equal to 0.0001) and pulmonary congestion (p equal to 0.0072). In the electrocardiogram, right atrium overload (p equal to 0.0118), ventricular arrhythmias (p equal to 0.0148) and heart rate (p equal to 0.027). In the echocardiogram, mitral regurgitation of grade 3 to 4 (p equal to 0.002), the left atrial to aortic ratio (p equal to 0.0001), and left ventricle ejection fraction (p equal to 0.0266). In multivariate analysis, the independent predictors were maximum cardiothoracic ratio (p equal to 0.0001), left ventricle ejection fraction (p equal to 0.0013), mitral regurgitation of grade 3 or 4 (p equal to 0.0017), functional class IV at presentation (p equal to 0.0028), and ventricular arrhythmias (p equal to 0.0253).

CONCLUSION

Children, who have these predictors of death should be considered for early heart transplantation when no improvement is observed in clinical treatment.

Presentation, management and outcomes of thrombosis for children with cardiomyopathy

BACKGROUND

Thrombosis in children with dilated and inflammatory cardiomyopathy is an unpredictable complication with potentially important morbidity.

OBJECTIVE

To determine the prevalence, associated factors, management and outcomes of thrombosis in this setting.

METHODS

Data were obtained from review of medical records. Factors associated with thrombosis and the impact on outcome were sought.

RESULTS

From 1990 to 1998, 66 patients that presented with dilated cardiomyopathy were followed for a median interval of 1.4 years (range 0 to 9.79 years) from first presentation. Thrombosis was diagnosed in four patients at presentation and in four patients during follow-up. Thrombosis was noted in one additional patient at examination after death. The overall nine-year period prevalence of thrombosis was 14%. Anticoagulation was started at presentation in 31% of patients. The mean left ventricular ejection fraction at presentation was significantly lower in those given anticoagulation (19+/-8%) versus those who were not (32+/-15%; P < 0.001). The mean ejection fraction at presentation was similar in those patients with (25+/-10%) versus those without thrombosis (28+/-15%; P = 0.44). During follow-up, 11 patients died and seven underwent cardiac transplantation. Kaplan-Meier estimates of freedom from death or transplantation were 88% at three months, 81% at one year and 70% at five years. Survival free of transplantation was not affected by thrombosis.

CONCLUSIONS

Thrombosis is common in children with cardiomyopathy, can occur at any time in the patients' clinical course and is not related to clinical features or survival free of transplantation. The relevance and prevention of thrombosis in this setting remains unclear.

Prospective single-arm protocol of carvedilol in children with ventricular dysfunction

The objective of this study was to evaluate the safety and efficacy of carvedilol in pediatric patients with stable moderate heart failure. We performed a single-arm prospective drug trial at three academic medical centers and the results were compared to historical controls. Patients were 3 months to 17 years old with an ejection fraction <40% in the systemic ventricle for at least 3 months on maximal medical therapy including ACE inhibitors. Treated patients were started on 0.1 mg/kg/day and uptitrated to 0.8 mg/kg/day or the maximal tolerated dose. Echocardiographic parameters of function were prospectively measured at entry and at 6 months. Two composite endpoints were recorded: severe decline in status and significant clinical change. Adverse events were reviewed by a safety committee. Data were also collected from untreated controls with dilated cardiomyopathy meeting entry criteria, assessed over a similar time frame. Twenty patients [12 dilated cardiomyopathy (DCM) and 8 congenital] with a median age of 8.4 years (range, 8 months to 17.8 years) were treated with carvedilol. Three patients discontinued the drug during the study. At entry, there was no statistical difference in age, weight, or ejection fraction between the treated group and controls. The ejection fraction of the treated DCM group improved significantly from entry to 6 months (median, 31 to 40%, p = 0.04), with no significant change in ejection fraction in the control group [median, 29 to 27%, p = not significant (NS)]. The median increase in ejection fraction was larger for the treated DCM group than for the untreated DCM controls (7 vs 0%, p = 0.05). By Kaplan-Meier analysis, time to death or transplant tended to be longer in treated patients (p = 0.07). The difference in the proportion of patients with severe decline in status or significant clinical change in the treated group was not significant compared to the controls (5 vs 12%, p = NS). We conclude that in this prospective protocol of pediatric patients, the use of adjunct carvedilol in the DCM group improved ejection fraction compared to untreated controls and trended toward delaying time to transplant or death.

Outcome of acute fulminant myocarditis in children

OBJECTIVES

To highlight clinical features and outcome of acute fulminant myocarditis (AFM) in children.

METHODS

Diagnostic criteria were (1) the presence of severe and acute heart failure; (2) left ventricular dysfunction on echocardiography; (3) recent history of viral illness; and (4) no history of cardiomyopathy.

RESULTS

Eleven children were included between 1998 and 2003, at a median age of 1 (0 to 9) year. Their mean left ventricular ejection fraction (LVEF) was 22 (SD 9)% at presentation. A virus was identified in five patients: human parvovirus B19 (n = 2), Epstein-Barr (n = 1), varicella zoster (n = 1), and coxsackie (n = 1). The median intensive care unit course was 13 (2-34) days. Intravenous inotropic support was required by nine patients and eight were mechanically ventilated. All patients received corticosteroid, associated with intravenous immunoglobulin in seven. Five patients experienced cardiocirculatory arrest that was successfully resuscitated in four. At a median follow up of 58.7 (33.8-83.1) months, the 10 survivors are asymptomatic with normalised LVEF.

CONCLUSION

Despite a severe presentation, the outcome of AFM is favourable. Aggressive symptomatic management is warranted and heart transplantation should be considered only when maximal supportive therapy does not lead to improvement.

Immunosuppressive treatment of chronic non-viral myocarditis

Inflammatory cardiomyopathy defined as myocarditis associated with cardiac dysfunction, represents a main cause of heart failure. Despite the improvement of diagnostic techniques, a specific standardized treatment of myocarditis is not yet available. The immunohistochemical detection of myocardial HLA up-regulation has been demonstrated useful in the identification of a sub-group of autoimmune inflammatory dilated cardiomyopathy (DCM) in part susceptible to immunosuppression. Recently, in a retrospective study, we defined the virologic and immunologic profile of responders and non-responders to immunosuppressive therapy of active lymphocytic myocarditis and chronic heart failure in patients who had failed to benefit from conventional supportive treatment. Non-responders were characterized by high prevalence (85%) of viral genomes in the myocardium and no detectable cardiac autoantibodies in the serum. Conversely, 90% of responders were positive for autoantibodies, while only 3 (15%) of them presented viral particles at PCR analysis on frozen endomyocardial tissue. With regard to the type of virus involved in non-responders, enterovirus, adenovirus, or their combination was associated with the worst clinical outcome. Hepatitis C virus (HCV) was the only viral agent of our series associated with detectable cardiac autoantibodies, suggesting a relevant immunomediated mechanism of damage by HCV and explaining the relief of myocardial inflammation after immunosuppressive treatment. The assessment of virologic and immunologic features of patients with biopsy-proven inflammatory cardiomyopathy may allow us to identify a specific treatment leading to recovery of cardiac function.

NT-proBNP as a marker for persistent cardiac disease in children with history of dilated cardiomyopathy and myocarditis

Children with myocarditis and dilated cardiomyopathy may recover clinically and echocardiographically. Plasma levels of the N-terminal segment of B-type natriuretic peptide prohormone (NT-proBNP), a sensitive marker for cardiac dysfunction, may reflect residual cardiac damage in these patients. The purpose of this study was to evaluate NT-proBNP status in pediatric patients with a history of myocarditis and dilated cardiomyopathy. Cardiac evaluation was performed and the levels of NT-proBNP were measured in 23 children who had a history of myocarditis or dilated cardiomyopathy. NT-proBNP levels were also measured in 56 age-matched control children. Nine of the 23 patients had evidence of left ventricular dysfunction (DCM group), whereas 14 had none (recovery). NT-proBNP levels were higher in the DCM group (3154 +/- 2858 pg/ml) than in the recovery group (122 +/- 75 pg/ml, p < 0.001) and the control group (113 +/- 96 pg/ml, p < 0.001). There was no difference between the recovery and the control groups (p = 0.45), and none of the recovered patients had a NT-proBNP level higher than the upper limit of normal. The area under the receiver operating characteristics curve for the diagnosis of persistent left ventricular dysfunction was 0.984. NT-proBNP levels correlated with echocardiographically derived shortening fraction and with clinical score. NT-proBNP is a good marker for persistent left ventricular dysfunction in children who have had myocarditis or cardiomyopathy. In this group of patients, NT-proBNP levels are normal in children who recover echocardiographically, suggesting no residual hemodynamic abnormalities.

Ventricular remodeling in children with left ventricular dysfunction secondary to various cardiomyopathies

The ventricular remodeling that occurs in adults with left ventricular (LV) dysfunction is characterized by a change in LV shape from an ellipse to more of a sphere and is associated with increased functional mitral regurgitation (MR), decreased exercise tolerance, and poor outcome. There are limited data on the occurrence and importance of LV remodeling in children with LV dysfunction. The purposes of this study were to evaluate in children with LV dysfunction (1) LV shape, (2) changes in LV shape as LV function improves, and (3) the relation between LV shape and functional MR. Children with LV dysfunction were identified and compared with controls. Patient demographics, treatment, and outcomes were noted. Echocardiograms were reviewed for LV function and shape (sphericity index). The echos of a subset of children whose LV ejection fractions (LVEFs) increased by >10% over a follow-up of >6 months were analyzed for changes in sphericity, mitral annulus size, and the degree of MR. Twenty-five children with LV dysfunction were compared with 37 age-matched controls. LV remodeling to a more spherical shape was inversely related to LVEF but was not associated with clinical outcome. In a subset of patients (n = 17) whose LVEFs improved, the reversal of remodeling (decrease in sphericity index) was associated with a decrease in MR and mitral annulus size. In conclusion, LV remodeling occurs in children with LV dysfunction. The reversal of this remodeling with a decrease in the degree of MR and the size of the mitral annulus occurs as systolic function improves.

Cardiac function assessment in patients with family history of nonhypertrophic cardiomyopathy: a prenatal and postnatal study

Nonobstructive cardiomyopathies (CMs) may be familial in 20â<euro>"55% of cases. Little is known about the role of fetal echocardiography in such cases. We evaluated the cardiac function serially pre- and postnatally in cases with a family history of nonobstructive CM. The fetal and postnatal studies were performed in the echocardiogarphy laboratory at a tertiary institution. Twenty-six cases from 16 families with a family history of CM were studied. Three fetal echocardiograms were performed at or near 18, 25, and 32 weeks of gestation for complete cardiac functional assessment. Postnatally clinical evaluation, electrocardiogram, and an echocardiogram were performed within the first 3 months, with serial reevaluation for those identified with CM. The mean follow-up was 46 +/- 9 months. Abnormal cardiac function was observed in 8 cases (30%). Six had a previously affected sibling, 1 had other family members affected, and 1 had both antecedents. Four had dilated CM diagnosed prenatally of which 1 recovered, 2 died in utero, and 1 died soon after birth. The remaining 4 had normal fetal echoes and were diagnosed with CM in the first 3 months of life. Three had dilated CM with recovery, and 1 had restrictive CM requiring cardiac transplantation. This study demonstrates a high familial recurrence rate of CM. Fetal echo is useful for early diagnosis, although a normal study does not preclude ventricular dysfunction at a later stage, justifying serial prenatal and postnatal evaluation. Early identification may expedite listing for transplantation.

Recombinant human growth hormone treatment for dilated cardiomyopathy in children

OBJECTIVE

Dilated cardiomyopathy (DCM) is one of the most common causes of heart failure among children and is often progressive despite maximal medical therapy. Heart failure is characterized by a number of neurohormonal abnormalities, including derangements in the growth hormone (GH)/insulin-like growth factor-1 (IGF-1) signaling axis. Decreased serum levels of GH, which acts on cardiac myocytes primarily through IGF-1, are associated with impaired myocardial growth and function, which can be improved with restoration of GH/IGF-1 homeostasis. In animal models and among human adults with heart failure attributable to DCM, treatment with GH results in acquisition of left ventricular (LV) mass and improved LV function, through a combination of mechanisms. We undertook this study to determine the effects of recombinant human GH on LV function and mass among children with stable LV dysfunction attributable to DCM.

METHODS

We performed a prospective, single-center, randomized, partially blinded, crossover trial among children 1 to 19 years of age with DCM and cardiac dysfunction of > or =6-month duration. After enrollment, patients were randomly assigned to receive treatment for 6 months with either conventional therapy (determined by the patient's primary cardiologist) plus recombinant human GH (0.025-0.04 mg/kg per day), administered as daily subcutaneous injections, or conventional therapy alone. Patients were then crossed over to the other treatment strategy for 6 months. The primary outcome measure was change in LV shortening fraction (SF). Other echocardiographic indices of LV function, somatic growth, and somatotropic/thyroid hormone levels were also monitored.

RESULTS

Only 8 of an intended 15 patients were enrolled, because of a combination of factors. Two patients withdrew during the study as a result of declining LV function requiring transplantation. LV SF did not change significantly during GH treatment, although both LV SF and LV SF z score were higher 6 months after cessation of GH treatment than at baseline. LV ejection fraction increased during GH therapy to a degree that approached significance. Height and weight percentiles for age increased significantly during GH therapy and remained higher 6 months after treatment. Annualized height velocity during GH treatment (13.7 +/- 3.3 cm/year, >97th percentile for all patients) was significantly higher than that after GH discontinuation (3.2 +/- 3.5 cm/year). Serum levels of IGF-1 and IGF-binding protein-3 were significantly higher after 6 months of GH treatment and 6 months after discontinuation of GH treatment than at baseline. There were no adverse events related to GH treatment.

DISCUSSION

In this prospective, single-center, randomized, partially blinded, crossover trial, recombinant human GH was administered to 8 pediatric patients with stable chronic heart failure secondary to DCM. Because of unanticipated difficulty enrolling eligible patients, the study was underpowered to detect changes in our primary outcome measure of the magnitude we projected. Nevertheless, we did observe several notable cardiovascular effects of GH treatment, including a trend toward improved LV ejection fraction during the course of GH treatment and significantly improved LV SF, SF z score, and LV end systolic stress z score 6 months after discontinuation of GH treatment (relative to baseline values). Given the fact that levels of IGF-1, the primary myocardial effector of GH signaling, remained significantly higher 6 months after GH treatment than at baseline, the improvement in LV functional indices 6 months after discontinuation of therapy may represent progression or perpetuation of a GH treatment effect. In addition to its cardiovascular effects, GH therapy was associated with significant acceleration of somatic growth. The benefits of GH were not associated with significant attributable side effects, although 2 patients developed progressive LV dysfunction during the study and underwent cardiac transplantation.

Carvedilol in children with cardiomyopathy: 3-year experience at a single institution

BACKGROUND

Carvedilol reduces mortality and hospitalization in adults with congestive heart failure. Limited information is available about its use in children.

METHODS

We reviewed the medical records of 24 children with dilated cardiomyopathy and left ventricular ejection fraction of <or=40%, who were treated with carvedilol as adjunct therapy to angiotensin-converting enzyme inhibitors, digoxin and diuretics.

RESULTS

Carvedilol was initiated 14.3 +/- 23.3 (mean +/- SD) months after the diagnosis of cardiomyopathy. Mean age at initiation of therapy was 7.2 +/- 6.4 years. The mean initial and maximum doses were 0.15 +/- 0.09 and 0.98 +/- 0.26 mg/kg/day. Adverse effects occurred in 5 patients (21%). Two patients (8%) required discontinuation of the drug within 5 weeks of the initial dose. The remaining 22 patients tolerated carvedilol for a mean follow-up period of 26.6 +/- 14.7 months. Among these 22 patients, mean left ventricular ejection fraction improved from 24.6 +/- 7.6% to 42.2 +/- 14.2% (p < 0.001), and mean sphericity index from 0.86 +/- 0.11 to 0.74 +/- 0.10 (p < 0.001). New York Heart Association functional class improved in 15 patients (68%). One patient (4%) died and 3 (14%) were transplanted.

CONCLUSIONS

Carvedilol, in addition to standard therapy for dilated cardiomyopathy in children improves cardiac function and symptoms; it is well tolerated, with minimal adverse effects, but close monitoring is necessary as it might worsen congestive heart failure and precipitate asthma. Control studies are necessary to assess the effect of carvedilol on mortality and hospitalization rates.

Evidence of adverse ventricular interdependence in patients with atrial septal defects

Right ventricular (RV) volume overload is associated with left ventricular (LV) distortion and dysfunction. The availability of transcatheter device closure of secundum atrial septal defect (ASD) provides an ideal model for investigating the immediate effects of elimination of RV volume overload and avoiding the confounding effects of surgery on LV function. Echocardiograms before and after device closure of ASD were analyzed for ejection fraction, percent changes in cross-sectional area and circumference, percent changes in free wall and septal endocardial lengths, and eccentricity. We enrolled 34 patients (median age 9 years) who underwent device closure of ASD (pulmonary to systemic shunt 1.6 +/- 0.4). Ejection fraction and LV end-diastolic volume, reflective of chamber preload, were significantly decreased in the presence of RV volume overload and normalized after defect closure with normalization of LV shape. Altered LV geometry secondary to RV volume overload was associated with regional variation in preload,such that diastolic circumference, a surrogate of myofiber preload, increased after closure of ASD secondary to a small increase in LV free wall arc length in conjunction with a much more significant increase in septal length. Thus, LV dysfunction associated with RV volume overload is secondary to altered chamber geometry and decreased myofiber preload. This physiology is immediately reversible and is independent of heart rate and afterload.

The epidemiology of childhood cardiomyopathy in Australia

BACKGROUND

The incidence and age distribution of primary cardiomyopathy in children are not well defined. We undertook a population-based, retrospective cohort study in Australia to document the epidemiology of childhood cardiomyopathy.

METHODS

We analyzed all cases of primary cardiomyopathy in children who presented between 1987 and 1996 and who were younger than 10 years of age. Children were recruited from multiple sources, and cases of cardiomyopathy were classified according to World Health Organization guidelines.

RESULTS

Over the 10-year period, 314 new cases of primary cardiomyopathy were identified, for an annual incidence of 1.24 per 100,000 children younger than 10 years of age (95 percent confidence interval, 1.11 to 1.38). Dilated cardiomyopathy made up 58.6 percent of cases, hypertrophic cardiomyopathy 25.5 percent, restrictive cardiomyopathy 2.5 percent, and left ventricular noncompaction 9.2 percent of cases. The incidence of all types of cardiomyopathy except restrictive declined rapidly after infancy. In 11 cases (3.5 percent), sudden death was the first symptom. There was a male predominance among children with hypertrophic and unclassified cardiomyopathy. Indigenous children had a higher incidence of dilated cardiomyopathy than nonindigenous children (relative risk, 2.67; 95 percent confidence interval, 1.42 to 4.63) and a higher rate of death as the presenting symptom (16.7 percent vs. 2.6 percent, P=0.02). Lymphocytic myocarditis was present in 25 of 62 children with dilated cardiomyopathy (40.3 percent) who underwent cardiac histologic examination within two months after presentation.

CONCLUSIONS

Lymphocytic myocarditis and left ventricular noncompaction are important causes of childhood cardiomyopathy in Australia. The timing and severity of presentation in children with cardiomyopathy are related to the type of cardiomyopathy, as well as to genetic and ethnic factors.

Non-transplant cardiac surgery for end-stage dilated cardiomyopathy in small children

Between October 1997 and December 2000, a total of 7 pediatric patients with end-stage dilated cardiomyopathy (DCM) were referred to our service for heart transplantation; non-transplant cardiac surgery was offered as a biologic bridge. Two patients died before surgery and the in-hospital surgical mortality rate was 50%: 75% in 4 patients who received emergency surgery and 0% in 2 patients who received urgent surgery. Non-transplant cardiac surgery improved clinical outcome and acted as a biologic bridge, instead of a mechanical bridge, to heart transplantation in small children with DCM and severe heart failure.

Diagnosis and management of pediatric myocarditis

Myocarditis is an insidious inflammatory disorder of the myocardium. As a clinical entity, it has been recognized for two centuries, but it defies traditional diagnostic tests. A greater understanding of the immune response underlying the pathobiology of the disorder can lead to a more rational therapeutic approach. The presentation, course and therapeutic options appear to be different in the pediatric compared with the adult population. An understanding of the difference between fulminant and acute progressive myocarditis has led to successful treatment strategies. A variety of new therapies are available, including antiviral agents, immunosuppression, and modulation of the biological response to inflammation. The specific question for patients with myocarditis is whether regimens designed to reduce or eliminate inflammation can provide clinical benefits compared with conventional heart failure therapy. This review highlights pathological mechanisms, modalities of diagnosis, and novel therapies which may improve outcomes.