Role of right ventricular endomyocardial biopsy in infants and children with suspected or possible myocarditis

Findings and Outcome of Transcatheter Right Ventricular Endomyocardial Biopsy and Hemodynamic Assessment in Children with Suspected Myocarditis or Cardiomyopathy

OBJECTIVE

The study objective is assessing findings and outcome in children with suspected cardiomyopathy (CMP) or myocarditis undergoing cardiac catheterization with transcatheter right ventricular endomyocardial biopsy (RV-EMB).

METHODS

All consecutive children undergoing cardiac catheterization with RV-EMB for suspected CMP/myocarditis between 2002-2021 were analysed regarding clinical presentation, cardiac biomarkers, periprocedural management, hemodynamic, histological/immunohistological findings, and outcome.

RESULTS

Eighty-five RV-EMBs were performed in 81 patients at a median age of 6.8 (IQR 9.9) years and a bodyweight of 20 (32.2) kg. Histological/immunohistological findings of RV-EMB revealed dilated CMP in 10 (12%), chronic myocarditis in 28 (33%), healing myocarditis in 5 (6%), acute myocarditis in 9 (11%), other heart muscle diseases in 23 (27%) (7 restrictive CMP, 5 hypertrophic CMP, 4 toxic/anthracycline-induced CMP, 4 endocardfibroelastosis, 1 arrhythmogenic right ventricular CMP, 1 laminin CMP, 1 haemangioma), no conclusive histology in 7 (8%), and normal histology in 3 (4%) patients. Median LVEDP was 17 mmHg (IQR 9), LAP 15 mmHg (10), and PVR 1.83 (1.87) Wood Units/m². There were 3 major complications (3%), all patients recovered without any sequelae. At follow-up (median 1153, IQR 1799 days) 47 (59%) patients were alive, 11 (13%) dead, 15 (18%) underwent cardiac transplantation, and 8 (9%) were lost to follow-up. Death/cardiac transplantation occurred within 3 years from RV-EMB. All patients with an acute myocarditis survived. NT-pro-BNP, echo parameters, and invasive hemodynamics correlate independently with death/cardiac transplant.

CONCLUSION

Hemodynamic invasive data and morphological findings in RV-EMB complete clinical diagnosis in children with suspected CMP/myocarditis and provide important information for further clinical management.

Advanced Heart Failure in Special Population-Pediatric Age

Heart failure (HF) is an important health care issue in children because of its considerable morbidity and mortality. Advanced HF encompasses patients who remained symptomatic despite optimal medical treatment and includes patients who require special management, such as continuous inotropic therapy, mechanical circulatory support, or heart transplantation (HT). HT is the gold standard for children with advanced HF; nonetheless, the number of suitable donors has not increased for decades, leading to prolonged waitlist times and increased mortality rates. Therefore, the role of pediatric mechanic circulatory support has been assessed as an alternative treatment in patients in whom heart transplant could not be performed. The authors discuss the epidemiology, causes, pathophysiology, clinical manifestation, medical treatment, device therapy, and HT in pediatric HF, and a particular emphasis was posed on patients with advanced HF.

Sudden cardiac death caused by myocarditis in persons aged 1-49 years: a nationwide study of 14 294 deaths in Denmark

Myocarditis is associated with an increased risk of sudden cardiac death (SCD) in the young. However, information on nationwide burden of SCD caused by myocarditis (SCD-myocarditis) is sparse. For this study all deaths among persons in Denmark aged 1–35 years in 2000–2009 and 36–49 years in 2007–2009 (27.1 million person-years) were included. Autopsy reports, death certificates, discharge summaries, and nationwide registries were used to identify all cases of SCD-myocarditis. In the 10-year study period, there were 14 294 deaths, of which we identified 1 363 (10%) SCD. Among autopsied SCD (n = 753, 55%), cause of death was myocarditis in 42 (6%) cases corresponding to an SCD-myocarditis incidence of 0.16 (95%CI: 0.11–0.21) per 100 000 person-years. Males had significantly higher incidence rates of SCD-myocarditis compared to females with an incidence rate ratio of 2.2 (95%CI: 1.1–4.1). Myocarditis was not registered as cause of death in any of the non-autopsied SCD (n = 610, 45%). In conclusion, after nationwide unselected inclusion of 14 294 deaths, we found that 6% of all autopsied SCD was caused by myocarditis. No cases of SCD-myocarditis were reported in the non-autopsied SCD, which could reflect underdiagnosing of myocarditis in non-autopsied SCD. Furthermore, our data suggest a female protection towards SCD-myocarditis.

In-hospital and post-discharge outcomes of pediatric acute myocarditis underwent after high-dose steroid or intravenous immunoglobulin therapy

Background

High-dose steroids and intravenous immunoglobulin (IVIG) are controversial treatments for pediatric patients with acute myocarditis. This study aimed to investigate their efficacies in the Taiwanese pediatric population.

Methods

This study evaluated 5563 acute myocarditis patients from the Taiwan’s National Health Insurance Research Database and identified 1542 pediatric patients hospitalized for acute myocarditis between January 1, 2001 and December 31, 2011. The exclusion criteria were age of > 11 years, associated cardiovascular comorbidities, autoimmune disease, malignancy before the index hospitalization, extracorporeal membrane oxygenation, intra-aortic balloon pumping, and dual therapy using IVIG and high-dose steroids.

Results

After 2:1 propensity score matching, we identified 208 subjects without steroid therapy and 104 subjects who received high-dose steroids. The mean age in that cohort was 2.6 ± 2.9 years, and high-dose steroid therapy had no significant effects on major in-hospital complications and post-discharge outcomes. After 2:1 propensity score matching, we identified 178 subjects without IVIG therapy and 89 subjects who received IVIG. The mean age in that cohort was 2.0 ± 2.1 years, and IVIG had no significant effects on the major outcomes.

Conclusions

The present study revealed that high-dose steroid or IVIG therapy had no significant effects on major in-hospital complications, late heart failure hospitalization, and long-term mortality.

Pediatric Heart Failure: A Practical Guide to Diagnosis and Management

Pediatric heart failure represents an important cause of morbidity and mortality in childhood. Currently, there are well-established guidelines for the management of heart failure in the adult population, but an equivalent consensus in children is lacking. In the clinical setting, ensuring an accurate diagnosis and defining etiology is essential to optimal treatment. Diuretics and angiotensin-converting enzyme inhibition are the first-line therapies, whereas beta-blockers and devices for electric therapy are less used in children than in adults. In the end-stage disease, heart transplantation is the best choice of treatment, while a left ventricular assist device can be used as a bridge to transplantation (due to the difficulties in finding organ donors), recovery (in the case of myocarditis), or destination therapy (for patients with systemic disease).

Right ventricular endomyocardial biopsy in children and adolescents with drug-refractory arrhythmia

Purpose This study aimed to assess the results of endomyocardial biopsy from the right ventricle to establish the possible cause for drug-refractory arrhythmias in children. Materials and methods We enrolled 19 consecutive young patients with drug-refractory arrhythmia, from 2010 to 2013, who underwent endomyocardial biopsy. Inclusion criteria were as follows: age <18 years with a structurally normal heart or mild changes in a structure of the heart initially diagnosed as arrhythmia-induced cardiomyopathy. Overall, 86 biopsies were performed in 19 patients. Histopathological analysis, immunohistochemistry, and polymerase chain reaction were used for the interpretation of the endomyocardial biopsy.

RESULTS

The mean age of the patient population was 14.1±2.9 year (range from 7 to 17 years). All these patients had a history of drug-refractory arrhythmia for >5 months (mean 30 months). Patients underwent a complete history investigation, physical examination, laboratory studies, echocardiography, electrocardiography, treadmill test, and Holter monitoring before endomyocardial biopsy; two patients with arrhythmogenic right ventricular dysplasia had implantable cardioverter defibrillator implantation and further appropriate successful device shocks. Myocarditis was diagnosed based on histopathological and immunohistological analyses in nine (47.4%) patients. Polymerase chain reaction was positive for viral genome in four of them; five patients had active myocarditis. Radiofrequency ablation was performed in 17 patients; five out of six (83%) endomyocardial biopsy-proved myocarditis patients had successful radiofrequency ablation. No significant complication was reported during ablation and endomyocardial biopsy.

CONCLUSIONS

Approximately half of the children with drug-refractory arrhythmia had unsuspected myocarditis according to the results of the endomyocardial biopsy.

Pediatric myocarditis: A sentinel of non-cardiac chronic diseases?

INTRODUCTION

Although long-term outcome studies in large pediatric myocarditis/cardiomyopathy populations have been reported in literature, none of them focused on comorbidities.

METHODS

All children and adolescents (age <18 years) treated with myocarditis at the Department of Pediatrics, University of Debrecen, Hungary were followed. Patients suffering from myocarditis during the period 1996-2011 were enrolled.

RESULTS

Over the 16-year period, a diagnosis of myocarditis was established in nine children. Their median age was 1.11 (0.03-8.71) years. Three of the nine patients died. Left ventricular dilatation and ejection fraction normalized within 1-21 months in the survivors. None of the cases progressed to dilated cardiomyopathy. Regarding non-cardiac comorbidities, myocarditis or recurrent peri-myocarditis preceded the manifestation of celiac disease in two patients, while cystic fibrosis was diagnosed after the improvement of cardiac function in another, and Alström syndrome was diagnosed several years after complete recovery from myocarditis in yet another patient.

CONCLUSION

These results suggest that manifestations of other chronic pediatric diseases may be more frequent among survivors of pediatric myocarditis. Prolonged follow-up of patients who survive myocarditis is therefore recommended not only to detect possible progression to cardiomyopathy but also to identify non-cardiac comorbidities.

Presentation, diagnosis, and medical management of heart failure in children: Canadian Cardiovascular Society guidelines

Pediatric heart failure (HF) is an important cause of morbidity and mortality in childhood. This article presents guidelines for the recognition, diagnosis, and early medical management of HF in infancy, childhood, and adolescence. The guidelines are intended to assist practitioners in office-based or emergency room practice, who encounter children with undiagnosed heart disease and symptoms of possible HF, rather than those who have already received surgical palliation. The guidelines have been developed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology, and are accompanied by practical Recommendations for their application in the clinical setting, supplemented by online material. This work does not include Recommendations for advanced management involving ventricular assist devices, or other device therapies.

Cardiac troponin T as a screening test for myocarditis in children

OBJECTIVE

The objective of this study was to define the test characteristics of cardiac troponin T (cTnT) in pediatric patients who presented with suspected myocarditis.

METHODS

We performed a retrospective cohort study of all patients at a large urban children's hospital 21 years or younger who had a cTnT test sent for evaluation for myocarditis over a 13-month period. Patients were excluded if they had any history of heart disease or cardiac arrest before presentation, or the cTnT was sent for reasons other than concern for myocarditis. Positive cases of myocarditis were defined by characteristic pathology findings, magnetic resonance imaging results, or diagnosis of the attending cardiologist at time of discharge.

RESULTS

Six hundred fifty-two patients had cTnT sent during the study period. Two hundred sixty were excluded because of prior history of heart disease, and 171 had the test sent for reasons other than concern for myocarditis. Of the 221 patients included in the study, 49 had an initial positive cTnT (≥0.01 ng/mL), whereas 172 had a negative test result. Eighteen cases of myocarditis were identified. All patients with myocarditis had an elevated cTnT at presentation. Using a cutoff value of 0.01 ng/mL or greater as a positive test, cTnT had a sensitivity of 100% (95% confidence interval [CI], 78%-100%), with a negative predictive value of 100% (CI, 97%-100%), and a specificity of 85% (CI, 79%-89%), with positive predictive value of 37% (CI, 24%-52%), in the diagnosis of myocarditis.

CONCLUSIONS

In children without preexisting heart disease, a cTnT level of less than 0.01 ng/mL can be used to exclude myocarditis.

Dilated cardiomyopathy presenting in childhood: aetiology, diagnostic approach, and clinical course

OBJECTIVE

To determine the outcome of dilated cardiomyopathy presenting in childhood and the features that might be useful for prognostic stratification.

METHODS

Retrospective study of 41 consecutive children affected by dilated cardiomyopathy - aged 0-14 years; median 33.4 plus or minus 49.25 - between 1993 and 2008. We reviewed the medical history to determine age at diagnosis, family history, previous viral illness, aetiology, symptoms and signs at presentation, treatment, and outcome. The diagnosis was made on the basis of cardiomegaly and evidence of poor left ventricular function by echocardiography. We also carried out a metabolic evaluation including blood lactate, pyruvate, carnitine, amino acids, urine organic acids, assessment of respiratory chain enzymes, and analysis of histopathological material. Survival curves were constructed by the Kaplan-Meier method.

RESULTS

Follow-up ranged from 10 days to 162 months - median 45.25 plus or minus 41.15 months. Freedom from death or cardiac transplantation was 68.3% at 5 years. The primary end-point of death/cardiac transplantation was associated with the need for intravenous inotropic support. A trend towards a poorer prognosis was found for age at diagnosis of more than 5 years and for a metabolic aetiology of dilated cardiomyopathy. For the children affected by cardiomyopathy as part of a multi-system involvement, mortality was 50%.

CONCLUSIONS

In children, dilated cardiomyopathy is a diverse disorder with outcomes that depend on cause, age, and cardiac failure status at presentation. Overt cardiac failure at presentation is a major prognostic factor for death or cardiac transplantation. Older age at presentation and metabolic aetiology may be associated with a poorer prognosis.

Endomyocardial biopsy--when and how?

Endomyocardial biopsy is a commonly performed useful procedure utilized for the evaluation of cardiac tissue. Biopsy may be used to monitor transplant rejection, but it has many other applications including the evaluation of myocarditis, cardiomyopathy, chest pain, arrhythmia, and secondary involvement by systemic diseases. Drug toxicity may be evaluated and neoplasms may be biopsied. Recent developments include advances in myocardial and viral molecular biology and advances in image or electrophysiology guided biopsy. The utility of endomyocardial biopsy is reviewed with consideration of these advances.

Routine performance of endomyocardial biopsy decreases the incidence of orthotopic heart transplant for myocarditis

BACKGROUND

In critically ill children presenting with dilated cardiomyopathy (DCM), the presence of myocarditis predicts an improved chance of myocardial recovery. Noninvasive differentiation of myocarditis from other causes of DCM is difficult. However, sensitivity of endomyocardial biopsy has been questioned.

METHODS

We reviewed clinical, echocardiographic, catheterization, and pathology data from all children admitted to the intensive care unit with DCM undergoing orthotopic heart transplantation since the inception of our transplant program in 1987 and all patients with definitively diagnosed myocarditis presenting since 1996.

RESULTS

Thirty-six patients with DCM underwent orthotopic heart transplantation. Cellular infiltrate was present in 3 of 36 (8.3%) explanted specimens. Pre-transplant biopsy was performed in 81%. No explanted heart demonstrated infiltrates after a negative biopsy. One biopsy was positive with negative explant histology after transplant 6 months later. No patient with biopsy-proven myocarditis died while listed for transplantation. Eleven additional patients with myocarditis did not undergo transplant. Ten have survived and experienced complete (n = 9) or near complete (n = 1) recovery of myocardial function. One patient died shortly after presentation from fulminant myocarditis. The 10 transplant-free survivors could not be easily distinguished from our transplant cohort by clinical features at presentation.

CONCLUSION

The incidence of cellular infiltrate in explanted hearts was significantly lower than that previously reported. Potentially, our aggressive myocarditis diagnostic protocol was useful in therapeutic stratification as a cohort of myocarditis patients avoided transplant and experienced complete recovery of myocardial function despite being difficult to distinguish clinically from our DCM transplant cohort at presentation.

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.

Therapy for pediatric myocarditis

Pediatric myocarditis is most often associated with the acute or subacute onset of congestive heart failure in a previously healthy child. Myocarditis presenting with acute, severe symptomatology, termed fulminant myocarditis, has a high rate of recovery. Aggressive supportive care is indicated in fulminant myocarditis, including mechanical circulatory support. For subacute heart failure, supportive care remains the mainstay of therapy for myocarditis. A number of uncontrolled pediatric studies using both immunosuppressive therapy and/or immunomodulating therapy with intravenous gamma globulin have suggested these therapies are safe and useful in treating pediatric myocarditis. However, translating these results into recommended, routine therapy for pediatric myocarditis is complicated by the high rate of spontaneous improvement of myocarditis with supportive care, and the lack of demonstrable benefit for immunosuppressive and immunomodulating therapies in blinded, randomized, placebo-controlled trials in adult myocarditis. Heart transplantation remains the final therapeutic option for children with myocarditis and intractable severe heart failure.

Outcomes for children with acute myocarditis

The optimum treatment for myocarditis in children is unknown. We present outcomes for this disease as seen in a large series of children. Thus, we identified all children seen with myocarditis at Children's Hospital of Pittsburgh since 1985, including only those with biopsy-proven myocarditis, or cardiac dysfunction and proof of concomitant cardiotropic viral infection. Outcomes were defined as complete recovery, incomplete recovery, and death or transplantation. We identified 41 patients, 37 proven by histology, and 4 patients who were too unstable for biopsy but had proof of viral infection. Of the group, 27 (66%) made a complete recovery, 4 (10%) had incomplete recovery, and 10 (24%) either died (5) or underwent transplantation (5). The median time to death or transplantation was 8.4 months, with a range from 1 day to 49 months. Steroids had been administered to 16 patients, of whom 10 made a complete recovery, 2 an incomplete recovery, 2 died, and 2 were transplanted. Intravenous immune globulin was given in isolation to one patient, who made a complete recovery, and to 18 in combination with steroids, of whom 12 made a complete recovery, 2 an incomplete recovery, 2 died, and 2 were transplanted. The remaining 6 patients received neither steroids nor intravenous immune globulin, and of these, 4 made a complete recovery, 1 was transplanted, and 1 died. Freedom from death or transplantation was 81% at 1 year, and 74% at 5 years, with no difference between the modes of treatments. The median time to recovery of function was also comparable between the groups. Thus, in our patients, treatment with intravenous immune globulin appeared to confer no advantage to steroid therapy alone. These data emphasise the need for randomised trials to assess the efficacy of current treatments, as well as that of new therapies.

Molecular diagnosis of myocarditis and dilated cardiomyopathy in children: clinicopathologic features and prognostic implications

Myocarditis is the most common cause of heart failure in children. We investigated viral etiology of myocarditis/dilated cardiomyopathy (DCM) in children and correlated molecular findings with pathologic and clinical data. Polymerase chain reaction (PCR) or reverse transcription (RT)-PCR were used to analyze 59 endomyocardial biopsies from 48 consecutive young (<18 yrs) patients (pts) with clinical and histologic diagnosis of myocarditis and DCM, employing primers designed to amplify specific sequences of various DNA and RNA viruses. Nucleic acids were successfully extracted in 41 pts and viral genomes were found in 20 (49%): 12 out of 26 pts (46%) with myocarditis, 6 out of 13 (46%) pts with DCM, and both patients with endocardial fibroelastosis. Enteroviruses were more common in DCM (72%), whereas adenoviruses and enteroviruses shared the same rate (36%) in myocarditis. The mumps virus genome was detected in the two pts with endocardial fibroelastosis. More diffuse inflammatory infiltrates and myocyte damage as well as more impaired left ventricular end diastolic volume and shortening fraction were noted in viral positive cases. PCR positive pts had a worse outcome, resulting in transplantation or death. Three out of 8 pts with viral myocarditis who underwent cardiac transplantation had recurrent PCR-proven graft viral infection. Viral myocarditis/DCM appeared to be a more severe disease than nonviral forms. Enteroviruses were more common in DCM, whereas adenoviruses were as frequent as enteroviruses in myocarditis. Persistence of viral infection was associated with disease deterioration. Viral myocarditis relapsed after transplantation.

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.

A practical approach for the diagnosis and management of dilated cardiomyopathy

Dilated cardiomyopathy (DCM) refers to a group of conditions of diverse etiology in which both ventricles are enlarged with reduced contractility. Certain correctable conditions associated with ventricular dysfunction can masquerade as DCM. Most of them can be identified with relatively inexpensive and readily available tests. A typical diagnostic work-up for a child with DCM also includes a number of investigations to identify the underlying cause, some of which are expensive and sophisticated. The average center in the developing world often does not have the facilities to carry out these investigations. The results of many of these investigations typically do not translate into a specific management strategy that makes a difference to prognosis. A significant number of children with DCM will eventually develop end-stage heart failure that requires cardiac transplantation with or without bridging procedures. This is an unrealistic option for the developing world. The management strategy of childhood DCM in the developing world needs to be tailored to the resources available with in a manner such that the overall prognosis is not substantially affected.

Clinical, electrocardiographic, and histologic correlations in children with dilated cardiomyopathy

OBJECTIVE

To determine whether presenting electrocardiography is related to histologic findings and clinical outcomes in children with dilated cardiomyopathy.

BACKGROUND

Lymphocytic myocarditis is an important cause of childhood dilated cardiomyopathy, the outcome of which is unclear. The results of non-invasive investigations are often used to infer the presence or absence of lymphocytic myocarditis.

METHODS

Thirty-four children, presenting acutely with dilated cardiomyopathy, underwent both early electrocardiography and endomyocardial biopsy. The parameters examined included heart rate, PR, QRS, and corrected QT intervals, R-wave voltages in Leads V(1) and V(6), S-wave voltages in Leads V(1) and V(6), and sum of SV(1) and RV(6). We expressed measurements as Z scores, based on published normal values for age and gender.

RESULTS

A total of 15 patients had lymphocytic myocarditis on endomyocardial biopsy (Group I), and 19 had non-specific histologic findings (Group II). We did not distinguish the 2 groups by age, time to endomyocardial biopsy, or duration of follow-up. Group I patients had significantly smaller R-wave Z scores in Leads V(1) and V(6), and combined S in V(1) and R in V(6) Z scores (p < 0.02 for each). The positive and negative predictive values of an R-wave amplitude in V(6) < 5th percentile were 75% and 65%, respectively, for the diagnosis of lymphocytic myocarditis. An R-wave amplitude in V(6) > 95th percentile had a positive and negative predictive value of 80% and 63%, respectively, for the diagnosis of idiopathic dilated cardiomyopathy. Survival and freedom from late cardiac dysfunction were more common among Group I patients compared with Group II (p <or= 0.02 for both).

CONCLUSION

Myocardial histology cannot reliably be inferred from the presenting electrocardiogram. Survival and outcome for children with lymphocytic myocarditis is better than for those with non-specific histology.

Complications of endomyocardial biopsy in children

OBJECTIVES

To evaluate the incidence of, and risk factors for, complications of endomyocardial biopsy in children.

BACKGROUND

Endomyocardial biopsy (EMB) is a low risk procedure in adults, but there is a paucity of data with regard to performing this procedure in children.

METHODS

Retrospective review of the morbidity and mortality of 1,000 consecutive EMB procedures.

RESULTS

One thousand EMB procedures (right ventricle 986, left ventricle 14) were performed on 194 patients from July 1987 through March 1996. Indications for EMB included heart transplant rejection surveillance (846) and the evaluation of cardiomyopathy or arrhythmia for possible myocarditis (154). Thirty-seven (4%) procedures were performed on patients receiving intravenous inotropic support. There was one biopsy related death, secondary to cardiac perforation, in a two-week-old infant with dilated cardiomyopathy. There were nine perforations of the right ventricle, eight occurring in patients with dilated cardiomyopathy and one in a transplant recipient. The transplant patient did not require immediate intervention; two patients required pericardiocentesis alone, and six underwent pericardiocentesis and surgical intervention. All nine perforations were from the femoral venous approach (p < 0.01). Multivariate analysis demonstrated that the greatest risk of perforation occurred in children being evaluated for possible myocarditis (p = 0.01) and in those requiring inotropic support (p < 0.01). Other complications included arrhythmia (5) and single cases of coronary-cardiac fistula, flail tricuspid leaflet, pneumothorax, hemothorax, endocardial stripping and seizure.

CONCLUSIONS

Risk of endomyocardial biopsy is highest in sick children with suspected myocarditis on inotropic support. However, EMB can be performed safely with very low morbidity in pediatric heart transplant recipients.

Heart transplantation in children: indications. Report of the Ad Hoc Subcommittee of the Pediatric Committee of the American Society of Transplantation (AST)

This review details the indications for heart transplantation in children. Contraindications have evolved from absolute to relative. Controversial issues remain and this paper represents a consensus of more than a dozen centers that have programs that remain active performing pediatric heart transplants.

Idiopathic dilated cardiomyopathy in children: prognostic indicators and outcome

OBJECTIVE

To determine the outcome of Finnish children and adolescents with idiopathic dilated cardiomyopathy (IDCM) and factors that might be useful as prognostic indicators.

METHODOLOGY

The clinical profile and course of 62 Finnish children and adolescents (median age, 13 months; range, 1 day to 20 years) with IDCM in 1980 to 1991 were evaluated to detect factors that might predict outcome. Factors studied included age, gender, family history, previous viral illness, and symptoms and signs at presentation. Furthermore, data on serial electrocardiographic, echocardiographic, and chest x-ray examinations, histologic findings, and treatments were analyzed.

RESULTS

During a mean (+/-SD) follow-up of 3.9 +/- 4.5 years (range, 1 day to 25 years), 10 patients (16%) recovered, 17 (27%) had residual disease, 4 (6.4%) underwent heart transplantation, and 31 (50%) died. Infants (<1 year of age) and adolescent (>/=15 years of age) male patients with progressing symptoms of left ventricular failure after initiation of medical therapy tended to have the poorest outcome. However, in multivariate analysis, only histologic evidence of endocardial fibroelastosis, clinical signs of right ventricular failure at presentation, and the need for anticoagulative therapy during follow-up, the last an expression of a severely impaired left ventricular systolic function, appeared to be significant predictors of long-term outcome.

CONCLUSIONS

Our study confirms that the outcome of children with IDCM still remains poor. However, a group of patients, mainly infants, make a full recovery. Adolescent male patients as well as infants suffering from endocardial fibroelastosis with persisting symptoms of congestive heart failure after initiation of medical therapy tend to have the poorest outcome. These patients need a careful follow-up at short time intervals and, in the case of lacking response to medical treatment with resulting growth failure and/or poor quality of life, should be offered urgent heart transplantation.