The clinical course of primary myocardial disease in infants and children

Diagnosis and Management of Myocarditis: An Evidence-Based Review for the Emergency Medicine Clinician

BACKGROUND

Myocarditis is a potentially fatal condition that can be misdiagnosed in the emergency department (ED) setting.

OBJECTIVE

The purpose of this narrative review article is to provide a summary of the background, pathophysiology, diagnosis, and management of myocarditis, with a focus on emergency clinicians.

DISCUSSION

Myocarditis occurs when inflammation of the heart musculature causes cardiac dysfunction. Symptoms may range from mild to severe and are often preceded by a viral prodrome. Laboratory assessment and an electrocardiogram can be helpful for the diagnosis, but echocardiography is the ideal test in the ED setting. Some patients may also require advanced imaging, though this will often occur during hospitalization or follow-up. Treatment is primarily focused on respiratory and hemodynamic support. Initial hemodynamic management includes vasopressors and inotropes, whereas more severe cases may require an intra-aortic balloon pump, extracorporeal membrane oxygenation, or a ventricular assist device. Nonsteroidal anti-inflammatory drugs should be avoided while intravenous immunoglobulin is controversial.

CONCLUSION

Myocarditis is a serious condition with the potential for significant morbidity and mortality. It is important for clinicians to be aware of the current evidence regarding the diagnosis, management, and disposition of these patients.

Lyme Myocarditis Presenting as Chest Pain in an Adolescent Girl

A previously healthy adolescent girl presented to the emergency department with new onset chest and right upper quadrant abdominal pain. Laboratory studies and imaging were consistent with myocarditis. She developed heart block after admission and required stabilization in the cardiac intensive care unit. Lyme serology returned positive, and her condition was diagnosed as Lyme disease-associated myocarditis.

Pediatric Cardiac Intensive Care Society 2014 Consensus Statement: Pharmacotherapies in Cardiac Critical Care Immune Therapy

OBJECTIVE

In this Consensus Statement, we review the etiology and pathophysiology of inflammatory processes seen in critically ill children with cardiac disease. Immunomodulatory therapies aimed at improving outcomes in patients with myocarditis, heart failure, and transplantation are extensively reviewed.

DATA SOURCES

The author team experience and along with an extensive review of the medical literature were used as data sources.

DATA SYNTHESIS

The authors synthesized the data in the literature to present current immumodulatory therapies. For each drug, the physiologic rationale, mechanism of action, and pharmacokinetics are synthesized, and the evidence in the literature to support the therapy is discussed.

CONCLUSIONS

Immunomodulation has a crucial role in the treatment of certain pediatric cardiac diseases. Immunomodulatory treatments that have been used to treat myocarditis include corticosteroids, IV immunoglobulin, cyclosporine, and azathioprine. Contemporary outcomes of pediatric transplant recipients have improved over the past few decades, partly related to improvements in immunomodulatory therapy to prevent rejection of the donor heart. Immunosuppression therapy is commonly divided into induction, maintenance, and acute rejection therapy. Common induction medications include antithymocyte globulin, muromonab-CD3, and basiliximab. Maintenance therapy includes chronic medications that are used daily to prevent rejection episodes. Examples of maintenance medications are corticosteroids, cyclosporine, tacrolimus, sirolimus, everolimus, azathioprine, and mycophenolate mofetil. Rejection of the donor heart is diagnosed either by clinically or by biopsy and is treated with intensification of immunosuppression.

Comparison of Immune Profiles in Fetal Hearts with Idiopathic Dilated Cardiomyopathy, Maternal Autoimmune-Associated Dilated Cardiomyopathy and the Normal Fetus

The etiology of idiopathic dilated cardiomyopathy (iDCM) remains unknown. Immune therapies have improved outcome in fetuses with DCM born to mothers with autoimmune disease (aDCM). The purpose of this retrospective study was to compare the myocardial B and T cell profiles in fetuses and neonates with idiopathic DCM (iDCM) versus autoimmune-mediated DCM (aDCM) and to describe the normal cell maturation within the human fetal myocardium. Of 60 fetal autopsy cases identified from institutional databases, 10 had aDCM (18-38 weeks), 12 iDCM (19-37 weeks) and 38 had normal hearts (11-40 weeks). Paraffin-embedded myocardium sections were stained for all lymphocyte (CD45), B cells (CD20, CD79a), T cells (CD3, CD4, CD7, CD8) and monocyte (CD68) surface markers. Two independent, blinded cell counts were performed. Normal hearts expressed all B and T cell markers in a bimodal fashion, with peaks at 22 and 37 weeks of gestation. The aDCM cohort was most distinct from normal hearts, with less overall T cell markers [EST -9.1 (2.6) cells/mm(2), p = 0.001], CD4 [EST -2.0 (0.6), p = 0.001], CD3 [EST -3.9 (1.0), p < 0.001], CD7 [EST -3.0 (1.1), p = 0.01] overall B cell markers [EST -4.9 (1.8), p = 0.01] and CD79a counts [EST -2.3 (0.9), p = 0.01]. The iDCM group had less overall B cell markers [EST -4.0 (1.8), p = 0.03] and CD79a [EST -1.7 (0.9), p = 0.05], but no difference in T cell markers. Autoimmune-mediated DCM fetuses have less B and T cell markers, whereas iDCM fetuses have less B cell markers compared with normal fetal hearts. The fetal immune system may play a role in the normal development of the heart and evolution of dilated cardiomyopathy.

Heart failure from heart muscle disease in childhood: a 5-10 year follow-up study in the UK and Ireland

Aims

Our original study, the first national prospective study of new‐onset heart failure from heart muscle disease in children, showed overall 1‐year survival of 82%, and event (death or transplantation)‐free survival of 66%. This study aimed to evaluate 5 + year outcomes of this important cohort.

Methods and results

All centres in the UK and Ireland with 1‐year event‐free survivors participated (n = 14). Anonymised data based on last hospital attendance and echocardiograms were reviewed. The investigator was blinded to outcome at the time of echo review. Of sixty‐nine 1‐year event‐free survivors, data were obtained on 64, with three lost to follow‐up and two moved abroad. There were three deaths at 2.2, 3.3 and 9.0 years after presentation and one transplant, at 5.2 years. Overall/event‐free survival was 77%/62% at 5 years and 73%/59% at 10 years, respectively. Overall and event‐free survival conditional on 1‐year survival was 94% at 5 years, and 89% at 10 years. For the 60 event‐free survivors, median (range) follow‐up duration was 9.04 (5.0–10.33) years for those still under review (n = 45), or time to discharge 5.25 (0.67–10.0) years (n = 15). Fifty‐eight were in New York Heart Association (NYHA) Class 1, and two in Class 2. Forty‐one out of sixty had normal echocardiograms at last follow‐up. Predictors of better longer‐term outcome were the same as for the original 1‐year follow‐up study, namely, younger age and higher fractional shortening measurement at presentation.

Conclusions

Children who survive the first year following their first presentation with significant heart failure from heart muscle disease have a good longer‐term outcome although there remains a small attrition rate.

The myocardium of fetuses with endocardial fibroelastosis contains fewer B and T lymphocytes than normal control myocardium

The observation that endocardial fibroelastosis (EFE) can result from an immune response to maternal autoantibody deposition in the fetal myocardium raises the possibility that the fetal immune system may contribute to the pathogenesis of idiopathic EFE and dilated cardiomyopathy (DCM). This study sought to characterize myocardial immune cell presence in fetuses and neonates with idiopathic EFE + DCM, in those with EFE + structural heart disease, and in normal control subjects. Paraffin tissue sections from fetuses identified from the pathology database were stained for B cell, T cell, macrophage, and general hematopoietic cell surface markers. Of the 14 fetuses included in the study, 5 had EFE + DCM, 4 had EFE + structural heart disease, and 5 were normal control fetuses. The EFE + DCM group had fewer B cells than the control group (0.15 vs. 0.44 cells/mm(2); p = 0.005). The EFE + heart disease group had both fewer B cells (0.18 vs. 0.44 cells/mm(2); p = 0.08) and T cells (0.29 vs. 0.80 cells/mm(2); p = 0.04) than the control group. The CD4/CD8 ratio was similar in the EFE + DCM and EFE + heart disease groups (1.0 vs. 0.9; p = 0.17) but higher in the EFE + DCM group than in the control group (0.9 vs. 0.3; p = 0.03). The myocardium of fetuses with EFE contains fewer B and T lymphocytes than normal control fetuses.

The management of myocarditis

Despite considerable advances in our understanding of myocarditis pathogenesis, the clinical management of myocarditis has changed relatively little in the last few years. This review aims to help bridge the widening gap between recent mechanistic insights, which are largely derived from animal models, and their potential impact on disease burden. We illustrate the pathogenetic mechanisms that are prime targets for novel therapeutic interventions. Pathway and pathogen-specific molecular diagnostic tests have expanded the role for endomyocardial biopsy. State of the art cardiac magnetic resonance imaging can now provide non-invasive tissue characterization and localize inflammatory infiltrates but imaging techniques are misleading if infectious agents are involved. We emphasize the gaps in our current clinical knowledge, particularly with respect to aetiology-based therapy, and suggest opportunities for high impact, translational investigations.

Update on myocarditis in children

PURPOSE OF REVIEW

Myocarditis is an uncommon pediatric illness, and it is frequently missed by medical personnel. It often masquerades as more common pediatric illnesses such as respiratory distress or gastrointestinal disease. Given that myocarditis accounts for 12% of sudden cardiac death among adolescents and young adults, the suspicion of this illness in the differential diagnosis of children presenting with nonspecific symptomatology and disease progression can be lifesaving.

RECENT FINDINGS

Historically, the diagnosis of myocarditis required endomyocardial biopsy. More recently ancillary diagnostic modalities have been used to help make the diagnosis less invasively. The use of laboratory testing, echocardiography, and cardiac MRI can now make the diagnosis in the absence of invasive biopsy and can help improve the diagnostic yield when biopsy is performed. Additionally, with an improved understanding of the pathophysiology of this disease, research has focused on novel therapeutic interventions such as immunoglobulin therapy and immunosuppressive therapy in the care of the patient with myocarditis.

SUMMARY

Myocarditis is a challenging diagnosis to make. With advent of newer diagnostic modalities and an improved understanding of the disease and its progression, there is a genuine hope that outcomes of pediatric myocarditis will be improved. The first step, however, is for medical providers to consider this entity in the differential diagnosis of patients with concerning presentation or illness history.

Myocarditis

Myocarditis is an uncommon, potentially life-threatening disease that presents with a wide range of symptoms in children and adults. Viral infection is the most common cause of myocarditis in developed countries, but other etiologies include bacterial and protozoal infections, toxins, drug reactions, autoimmune diseases, giant cell myocarditis, and sarcoidosis. Acute injury leads to myocyte damage, which in turn activates the innate and humeral immune system, leading to severe inflammation. In most patients, the immune reaction is eventually down-regulated and the myocardium recovers. In select cases, however, persistent myocardial inflammation leads to ongoing myocyte damage and relentless symptomatic heart failure or even death. The diagnosis is usually made based on clinical presentation and noninvasive imaging findings. Most patients respond well to standard heart failure therapy, although in severe cases, mechanical circulatory support or heart transplantation is indicated. Prognosis in acute myocarditis is generally good except in patients with giant cell myocarditis. Persistent, chronic myocarditis usually has a progressive course but may respond to immunosuppression.

Pediatric myocarditis: emergency department clinical findings and diagnostic evaluation

OBJECTIVE

The goal was to determine, in children with myocarditis, the frequency of various presenting symptoms and the sensitivity of clinical and laboratory investigations routinely available in the emergency department.

METHODS

We performed a retrospective review of all patients < 18 years of age who were diagnosed as having myocarditis at our institution between May 2000 and May 2006 and who initially presented to an emergency department. Patients were categorized as having definite myocarditis (positive endomyocardial biopsy results) or probable myocarditis (diagnosis assigned by a pediatric cardiologist on the basis of history, physical examination, and investigation results in the absence of an endomyocardial biopsy or in the presence of negative biopsy results). All patients were assigned a predominant category of symptoms at presentation on the basis of criteria defined a priori.

RESULTS

There were 16 cases of definite myocarditis and 15 cases of probable myocarditis. The age distribution was nonnormal, with peaks among children < or = 3 years and > or = 16 years of age. Of 14 patients who were seen by a physician before being diagnosed with myocarditis, 57% were originally diagnosed as having pneumonia or asthma. Thirty-two percent of patients presented with predominantly respiratory symptoms, 29% had cardiac symptoms, and 6% had gastrointestinal symptoms. Although evidence of cardiac dysfunction was frequently present in the form of respiratory distress, only a minority of children had evidence of hepatomegaly or abnormal cardiac examination results. The sensitivities of electrocardiograms and chest radiographs as screening tests were 93% and 55%, respectively. Among laboratory tests studied, aspartate aminotransferase measurement was the most sensitive (sensitivity: 85%).

CONCLUSIONS

Children with myocarditis present with symptoms that can be mistaken for other types of illnesses; respiratory presentations were most common. When clinical suspicion of myocarditis exists, chest radiography alone is an insufficient screening test. All children should undergo electrocardiography. Aspartate aminotransferase testing may be a useful adjunctive investigation.

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.

Experience and result of extracorporeal membrane oxygenation in treating fulminant myocarditis with shock: what mechanical support should be considered first?

BACKGROUND

Extracorporeal membrane oxygenation (ECMO), instead of ventricular assist device (VAD), could work as the first-line treatment of choice for fulminant myocarditis (FM) with profound shock if intraaortic balloon pumping was inadequate. We reviewed our experience in treating FM with ECMO and compared it with the literature that described the use of VAD.

METHODS

Fifteen consecutive patients (age 27.1 +/- 19.3 years) who had FM with profound shock were rescued with ECMO emergently. Hypotension, depressed left ventricular ejection fraction (19.1% +/- 6.1%), and oliguria occurred in all patients with high-dose catecholamine (inotropic equivalents: 69.0 +/- 37.7 microg/kg/min) and ventilator support. Before ECMO support, 6 patients received intraaortic balloon pumping support, 5 received external cardiac massage, 5 needed a temporary pacemaker, and 4 needed continuous hemofiltration. The pre-ECMO cardiac enzyme and liver enzyme levels were abnormally high.

RESULTS

Fourteen patients (93.3%) could be weaned off mechanical support. Three of 14 successfully weaned patients died later as a result of complications. Survival to discharge was 73.3%, and none of survivors needed heart transplantation. The ECMO duration was 137.7 +/- 74.5 hours. The ECMO-related neurological complication (6.7%) and the reexploration rate for hemostasis (8.9%) were lower than the myocarditis group supported by VAD from the literature review. The 11 survivors exhibited no cardiac dysfunction during the follow-up period.

CONCLUSIONS

Owning to advantages of fewer complications, easier application, and biventricular support, ECMO can be considered as the first-line treatment of mechanical support for FM with profound shock when intraaortic balloon pumping is inadequate or infeasible.

Decision making for mechanical cardiac assist in pediatric cardiac surgery

The practice of pediatric cardiac surgery has evolved to the point where the majority of patients operated on represent the most complex end of the spectrum of congenital heart disease. Given this, the potential role for mechanical cardiac assist will continue to expand. Although extracorporeal membrane oxygenation remains the mainstay of mechanical circulatory assist, the increased use of centrifugal ventricular assist devices is changing the approach to the treatment of acute cardiac failure. A range of newly developed implantable and paracorporeal devices is beginning to make its way into the clinical practice of pediatric cardiac surgery. This article addresses the different types of support available for mechanical cardiac assist and the clinical considerations in selecting the appropriate device.

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.

The effect of coenzyme Q10 on idiopathic chronic dilated cardiomyopathy in children

The objective of this study was to assess the effect of coenzyme Q10 (CoQ10) as supplementation to conventional antifailure drugs on quality of life and cardiac function in children with chronic heart failure due to dilated cardiomyopathy (DCM). The study was an open-label prospective study performed in two of the largest pediatric centers in Thailand from August 2000 to June 2003. A total of 15 patients with idiopathic chronic DCM were included, with the median age of 4.4 years (range, 0.6-16.3). Presenting symptoms were congestive heart failure in 12 cases (80%), cardiogenic shock in 2 cases (13.3%), and cardiac arrhythmia in 1 case (6.7%). Sixty-one percent of patients were in the New York Heart Association functional class 2 (NYHA 2), 31% in NYHA 3, and 8% in NYHA 4. Cardiothoracic ratio from chest x-ray, left ventricular ejection fraction, and left ventricular end diastolic dimension in echocardiogram were 0.62 (range, 0.55-0.78), 30% (range, 20-40), and 5.2 cm (range, 3.8-6.5), respectively. CoQ10 was given at a dosage of 3.1 ? 0.6 mg/kg/day for 9 months as a supplementation to a fixed amount of conventional antifailure drugs throughout the study. At follow-up periods of 1, 3, 6, and 9 months, NYHA functional class was significantly improved, as was CT ratio and QRS duration at 3 and 9 months follow-up with CoQ10 when compared to the baseline and post-discontinuation of CoQ10 at 9 months (range, 4.8-10.8). However, when multiple comparisons were taken into consideration, there was no statistical significant improvement. In addition to the conventional antifailure drugs, CoQ10 may improve NYHA class and CT ratio and shorten ventricular depolarization in children with chronic idiopathic DCM.

Reversible cardiomyopathy caused by an uncommon form of congenital adrenal hyperplasia

A child with 11, beta-hydroxylase deficiency, an unusual variant of congenital adrenal hyperplasia, presented with dilated cardiomyopathy. Congestive heart failure and dilatation of ventricles resolved with hydrocortisone replacement therapy. This case highlights the importance of complete history and physical examination of children with dilated cardiomyopathy.

The usefulness of surface electrocardiogram as a prognostic predictor in children with idiopathic dilated cardiomyopathy

We investigated the interrelations between surface electrocardiographic changes and clinical outcomes in children with idiopathic dilated cardiomyopathy (DCMP). 33 patients (19 boys, 14 girls) were classified into two groups; group I (15) who were in poor clinical status or dead; and group II (18) who showed good clinical status. Group I had larger LV dimensions compared to group II (Gr I vs. Gr II; LVEDD, 52 +/-11 vs. 42+/-7 (mm); LVESD, 43+/-12 vs. 30+/-5 (mm); p<0.05). QRS duration was prolonged in Gr I compared to Gr II and normal (Gr I, 84+/-28; Gr II, 66+/-12; normal control, 67+/-9). The QRS duration was correlated with the dimensions of left ventricle (LV). Corrected QT and JT interval and dispersions of QT in the DCMP group showed a significant difference compared to the normal control, however there was no significant difference between Gr I and II. In conclusion, QRS duration was correlated with ventricular dimension and clinical outcome in children with idiopathic dilated cardiomyopathy. Irrespective of increased ventricular inhomogeneity, QT dispersion could not be used to predict long-term prognosis.

The incidence of pediatric cardiomyopathy in two regions of the United States

BACKGROUND

Population-based data on the incidence of pediatric cardiomyopathy are rare because of the lack of large, prospective studies.

METHODS

Since 1996 the Pediatric Cardiomyopathy Registry sponsored by the National Heart, Lung, and Blood Institute has collected data on all children with newly diagnosed cardiomyopathy in New England and the Central Southwest region (Texas, Oklahoma, and Arkansas) of the United States. We report on all children in these regions who received this diagnosis between 1996 and 1999.

RESULTS

We identified 467 cases of cardiomyopathy, for an overall annual incidence of 1.13 per 100,000 children (95 percent confidence interval, 1.03 to 1.23). The incidence was significantly higher among infants younger than 1 year old than among children and adolescents who were 1 to 18 years old (8.34 vs. 0.70 per 100,000, P<0.001). The annual incidence of cardiomyopathy was lower among white children (upper-bound estimate, 1.06 cases per 100,000) than among black children (lower-bound estimate, 1.47 per 100,000; P=0.02) and higher among boys than among girls (1.32 vs. 0.92 per 100,000, P<0.001). The incidence also varied significantly by region: 1.44 cases per 100,000 in New England and 0.98 per 100,000 in the Central Southwest region (P<0.001). When categorized according to type, dilated cardiomyopathy made up 51 percent of the cases, hypertrophic cardiomyopathy 42 percent, and restrictive or other types 3 percent; 4 percent were unspecified. There was no significant difference in the incidence rates according to the year.

CONCLUSIONS

The estimated incidence of pediatric cardiomyopathy in two large regions of the United States is 1.13 cases per 100,000 children. Most cases are identified at an early age, and the incidence varies according to sex, region, and racial or ethnic origin.

Endocardial fibroelastosis associated with maternal anti-Ro and anti-La antibodies in the absence of atrioventricular block

OBJECTIVES

This study was designed to document the association of endocardial fibroelastosis (EFE) and maternal autoantibodies.

BACKGROUND

Neonatal lupus erythematosus is associated with the transplacental passage of maternal anti-Ro and anti-La antibodies, leading to complete atrioventricular block (CAVB). In some cases, CAVB is associated with EFE. Isolated EFE may be independently related to maternal anti-Ro and anti-La antibodies.

METHODS

We identified three cases (one fetus and two infants, all female) of isolated EFE in infants born to autoantibody-positive mothers in the absence of CAVB. Demographics, echocardiograms, and pathology were reviewed. Immunohistochemical analyses for immunoglobulin (Ig)G, IgM, IgA, T-cell, B-cell, and terminal deoxynucleoleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) (test for cell apoptosis) staining were performed on multiple sections of the heart in each case and compared with negative controls.

RESULTS

Two cases died and one received a cardiac transplant. All three cases had histologically confirmed EFE. All cases demonstrated significant diffuse IgG infiltration. To a lesser extent, myocardial tissue was also positive for IgM, CD43, and Granzyme B. None of the specimens were TUNEL positive.

CONCLUSIONS

These are the first reported cases of isolated EFE associated with maternal anti-Ro and anti-La antibodies in the absence of CAVB. The diffuse deposition of IgG and the presence of a T-cell infiltrate throughout the myocardium suggest that the transplacental passage of maternal autoantibodies induces an immune reaction within the myocardium, leading to isolated EFE. Autoantibody-mediated EFE may be an etiologic factor in cases of fetal and neonatal "idiopathic" dilated cardiomyopathy.

Mechanical circulatory support for infants and children with cardiac disease

Mechanical circulatory support is assuming an expanding role in the practice of congenital cardiac surgery. Extracorporeal membrane oxygenation and centrifugal ventricular assist devices are still the mainstay of mechanical circulatory support for children; however, newly developed pulsatile, paracorporeal ventricular assist devices designed for pediatric applications are achieving increased utilization. In addition, several new, continuous flow devices that are under development as fully implantable systems for adults, ultimately may be useful for pediatric patients.

Maternal anti-Ro and anti-La antibody-associated endocardial fibroelastosis

BACKGROUND

Maternal anti-Ro and anti-La antibodies are associated with congenital heart block (CHB). Although endocardial fibroelastosis (EFE) has been described in isolated cases of autoantibody-mediated CHB, the natural history and pathogenesis of this disease are poorly understood.

METHODS AND RESULTS

We retrospectively reviewed the clinical history, echocardiography, and pathology of fetuses and children with EFE associated with CHB born to mothers positive for anti-Ro or anti-La antibodies at 5 centers. Thirteen patients were identified, 6 with a prenatal and 7 with a postnatal diagnosis. Six mothers were positive for anti-Ro and anti-La antibodies, and 7 were positive for anti-Ro antibodies only. Only 1 mother had autoimmune disease. Severe ventricular dysfunction was seen in all fetal and postnatal cases. Four fetal and 3 postnatal cases had EFE at initial presentation. However, 2 fetal and 4 postnatal cases developed EFE 6 to 12 weeks and 7 months to 5 years from CHB diagnosis, respectively, even despite ventricular pacing in 6 postnatal cases. Eleven (85%) either died (n=9) or underwent cardiac transplantation (n=2) secondary to the EFE. Pathologic assessment of the explanted heart, available in 10 cases, revealed moderate to severe EFE in 7 and mild EFE in 3 cases, predominantly involving the left ventricle. Immunohistochemistry in 4 cases (including 3 fetuses) demonstrated deposition of IgG in 4 and IgM in 3 and T-cell infiltrates in 3 cases, suggesting an immune response by the affected fetus or child.

CONCLUSIONS

EFE occurs in the presence of autoantibody-mediated CHB despite adequate ventricular pacing. Autoantibody-associated EFE has a very high mortality rate, whether developing in fetal or postnatal life.

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.

Impaired cardiac adrenergic innervation assessed by MIBG imaging as a predictor of treatment response in childhood dilated cardiomyopathy

OBJECTIVE

To evaluate the prognostic value of metaiodobenzylguanidine (MIBG) imaging in childhood cardiomyopathy.

DESIGN

Prospective cohort study.

SETTING

Tertiary referral centre.

PATIENTS

40 children (21 boys, 19 girls; mean (SD) age, 7.0 (5.6) years) with heart failure resulting from idiopathic dilated cardiomyopathy (n = 23) or various other disorders (n = 17).

METHODS

At the initial examination, cardiac (123)I-MIBG uptake and release, circulating noradrenaline (norepinephrine) concentration, x ray cardiothoracic ratio, and echocardiographic variables were recorded. Cardiac MIBG uptake was obtained by measuring the heart to mediastinum activity ratio on the planar image obtained four hours after MIBG injection. MIBG washout rate was evaluated using relative decrease in cardiac activity measured at 20 minutes and four hours. Patients were treated with angiotensin converting enzyme inhibitors, diuretics, and digitalis, and were followed up for 12 (10) months. Fifteen patients did not respond to medical treatment (12 heart transplants; three deaths), and 25 did respond (improved or stable).

RESULTS

Cardiac MIBG uptake was positively correlated with x ray cardiothoracic index (r = 0.55, p = 0.0008) and echocardiographic left ventricular fractional shortening (r = 0.68, p < 0.0001). Among all the clinical and laboratory variables tested, multivariate discriminant analysis showed that the only independent predictor of an unfavourable outcome was a low MIBG uptake (p < 0.001). Survival curves had a mean threshold value of 1.54 for MIBG uptake.

CONCLUSIONS

Impaired cardiac adrenergic innervation is strongly related to adverse outcome in children with dilated cardiomyopathy, independently of the aetiology. MIBG imaging may help to stratify risk in such patients.

Congenital heart block: development of late-onset cardiomyopathy, a previously underappreciated sequela

OBJECTIVE

We report 16 infants with complete congenital heart block (CHB) who developed late-onset dilated cardiomyopathy despite early institution of cardiac pacing.

BACKGROUND

Isolated CHB has an excellent prognosis following pacemaker implantation. Most early deaths result from delayed initiation of pacing therapy or hemodynamic abnormalities associated with congenital heart defects.

METHODS

A multi-institutional study was performed to identify common clinical features and possible risk factors associated with late-onset dilated cardiomyopathy in patients born with congenital CHB.

RESULTS

Congenital heart block was diagnosed in utero in 12 patients and at birth in four patients. Ten of 16 patients had serologic findings consistent with neonatal lupus syndrome (NLS). A pericardial effusion was evident on fetal ultrasound in six patients. In utero determination of left ventricular (LV) function was normal in all. Following birth, one infant exhibited a rash consistent with NLS and two had elevated hepatic transaminases and transient thrombocytopenia. In the early postnatal period, LV function was normal in 15 patients (shortening fraction [SF] = 34 +/- 7%) and was decreased in one (SF = 20%). A cardiac pacemaker was implanted during the first two weeks of life in 15 patients and at seven months in one patient. Left ventricular function significantly decreased during follow-up (14 days to 9.3 years, SF = 9% +/- 5%). Twelve of 16 patients developed congestive heart failure before age 24 months. Myocardial biopsy revealed hypertrophy in 11 patients, interstitial fibrosis in 11 patients, and myocyte degeneration in two patients. Clinical status during follow-up was guarded: four patients died from congestive heart failure; seven required cardiac transplantation; one was awaiting cardiac transplantation; and four exhibited recovery of SF (31 +/- 2%).

CONCLUSIONS

Despite early institution of cardiac pacing, some infants with CHB develop LV cardiomyopathy. Patients with CHB require close follow-up not only of their cardiac rate and rhythm, but also ventricular function.

Design and implementation of the North American Pediatric Cardiomyopathy Registry

The Pediatric Cardiomyopathy Registry (PCMR) was established to describe the epidemiologic features and clinical course of selected cardiomyopathies in patients aged 18 years or younger and to promote the development of etiology-specific treatments. Sixty-one private and institutional pediatric cardiomyopathy practices in the United States and Canada were recruited to participate in the PCMR. The registry consists of a prospective, population-based cohort of patients in 2 regions (New England and the Central Southwestern United States) and a retrospective cohort of patients diagnosed between 1991 and 1996. Annual follow-up data are collected on all patients. As of June 1999, the PCMR consisted of 337 prospectively identified and 990 retrospectively identified patients. The PCMR has demonstrated the feasibility of establishing a large database of sociodemographic and clinical information on children with pediatric cardiomyopathy. Through this cooperative effort, the PCMR will obtain precise estimates of the incidence of pediatric cardiomyopathy and a better understanding of the natural history of this disease.

Rescue for acute myocarditis with shock by extracorporeal membrane oxygenation

BACKGROUND

Acute myocarditis (AM) complicated with refractory cardiogenic shock carries a very high mortality. We report our experience in treating these patients, who were rescued by extracorporeal membrane oxygenation (ECMO) and intravenous immunoglobulin.

METHODS

Over a 5-year period, 5 patients with AM were rescued with ECMO in our hospital. Femoral venoarterial ECMO was performed in 4 patients, and right atrium-left atrium-aorta ECMO in the other 1 due to ventricular dysfunction. Hemofiltration was applied to 3 patients. Marked elevated creatine kinase, its MB form, and troponin T (TnT) were found before ECMO.

RESULTS

All the patients could be weaned off the ECMO after 140.0+/-57.7 hours of ECMO support. One patient died of multiple organ failure 10 days later after removal of ECMO, resulting in a 20% mortality. Renal function returned to normal in all survivors. The 4 survivors were discharged uneventfully in 23.3+/-8.3 days and resumed functional class I status. The TnT level declined to the low level within 3 days (slope -4.94+/-1.18 ng/mL/day), and might be an indicator of good recovery of myocardium.

CONCLUSIONS

ECMO can provide an effective and simple treatment for critical AM with a satisfactory result and reduce the possibility of progressive cardiomyopathy.

Extracorporeal life support in pediatric patients with heart failure

The prognosis of patients with end-stage heart failure presenting with acute clinical deterioration is poor. Extracorporeal membrane oxygenation (ECMO), however, can provide univentricular and biventricular cardiac support which has led to the extended application of ECMO to infants and children. With improving results, indications and modalities of mechanical support have changed, and mechanical bridge to cardiac transplantation will offer extended survival for selected patients. The purpose of this article is to provide comprehensive data of pediatric cardiac support and to discuss the central role of echocardiography in the estimation of cardiac performance during mechanical support. As a conclusion, one can predict that the encouraging results of today will lead to further technological developments, which will create individual technical solutions of different clinical applications.

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.

Pediatric myocardial disease

Cardiomyopathies are diseases of the heart muscles. This article reviews the causes, clinical presentation, diagnosis, management, and long-term outcomes of dilated and hypertrophic cardiomyopathy.

Left ventricular pannus causing inflow obstruction late after mitral valve replacement for endocardial fibroelastosis

A case of mitral stenosis following mitral valve replacement in a patient with endocardial fibroelastosis is reported. A 14-year-old boy presented with cardiac failure. He had been diagnosed as having endocardial fibroelastosis at the age of 7 months and had undergone resection of endocardial fibrous tissue in the left ventricle at that time. Five years later his mitral valve was resected owing to mitral stenosis, with Bjork-Shiley valve replacement. Cross-sectional echocardiography on this admission showed restrictive left ventricular inflow due to a thickened immobile prosthetic valve with severely dyskinetic left ventricle (ejection fraction 8%). The electrocardiogram showed atrioventricular reentry tachycardia. Despite direct current cardioversion and continual amiodarone infusion he suffered a cardiac arrest and died 12 days after admission. Postmortem examination showed left ventricular endocardial fibroelastosis with severe inflow obstruction due to the formation of a complete fibrous ring of pannus/fibrosis around the prosthetic margin on the ventricular aspect of the left ventricle. This complication has not previously been described in children after mitral valve replacement.

Natural history of Alström syndrome in early childhood: onset with dilated cardiomyopathy

Alström syndrome is an autosomal recessive disorder characterized by cone-rod dystrophy, obesity, hearing impairment, and diabetes caused by insulin resistance. By reviewing the charts of eight patients followed for periods of 2 to 22 years, we established the natural history of this syndrome during childhood. Five patients, in four families, were seen between the ages of 3 weeks and 4 months with a dilated cardiomyopathy, a previously unrecognized feature of the syndrome. Photophobia and nystagmus were first documented in the eight patients between the ages of 5 months and 15 months. In all patients, electroretinography initially showed a severe cone impairment with mild (2/8) or no (6/8) rod involvement. Electroretinograms, obtained again at ages 9 to 22 years for four patients, revealed extinguished rod-and-cone responses. Obesity developed during childhood in seven patients, in at least three of them before age 2 years. Hearing impairment (5/8) and diabetes/glucose intolerance (4/8) were diagnosed at the end of the first decade or during the second decade. This constellation of features should facilitate early diagnosis of the syndrome.

Heart transplantation for dilated cardiomyopathy

Between 1988 and 1994, 23 patients underwent heart transplantation for dilated cardiomyopathy. The age of the 13 boys and 10 girls was from 8 months to 16 years (mean 7.1 years). Selection criteria included failure to thrive despite maximal antifailure treatment and/or intravenous inotrope dependence. The aetiology of cardiomyopathy was idiopathic (n = 13), congenital (n = 3), anthracycline induced (n = 4), Barth's syndrome (n = 1), and maternal systemic lupus erythematosus (n = 2). The waiting period of heart transplantation ranged from one day to 147 days (mean 22 days). Maintenance immunosuppression included cyclosporin, azathioprine, and prednisolone. Follow up after transplantation was from one month to 62 months (median 27 months) with a mean actuarial survival of 95% at one year and 87% at three years. Four patients developed coronary artery disease, one of whom died as a consequence 15 months after heart transplantation. Heart transplantation has emerged as an acceptable therapeutic option, at least in the short term, for patients with dilated cardiomyopathy.

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

BACKGROUND

For patients with acute dilated cardiomyopathy, definition of prognosis and of clinical features predictive of outcome is particularly important due to the availability of cardiac transplantation and other innovative treatment strategies.

METHODS AND RESULTS

We reviewed our experience with 24 children under 2 years of age with dilated congestive cardiomyopathy to determine outcome and potential predictive variables. Clinical, serological, ECG, echocardiographic, hemodynamic, and histological findings were analyzed. Idiopathic cardiomyopathy or myocarditis constituted 29% of the patients presenting with congestive heart failure without structural heart disease. Among these patients, 45% recovered completely, 25% survived with persistent left ventricular dysfunction, and 30% died. All except one of the deaths occurred during the first 2 months after presentation. Poorer outcome and higher mortality were associated with a more severely depressed left ventricular ejection fraction and/or a more spherical left ventricular shape at presentation. Histological evidence of myocardial inflammation was a favorable prognostic indicator, whereas histological evidence of endocardial fibroelastosis was associated with a poor outcome. During the recovery phase, diastolic volume fell rapidly. Ventricular mass was elevated from the earliest observations and fell more slowly, with persistent elevation of the mass-to-volume ratio up to 2 years. Function and contractility improved over the first several months in most patients who recovered, although in occasional patients continued improvement was seen for as long as 2 years after presentation.

CONCLUSIONS

Histological and echocardiographic features can be used to identify patients at particularly high risk for death. To have any impact on outcome, decisions about cardiac transplantation must be reached rapidly, since almost all deaths occurred within the first 2 months after presentation. Recovery of function is often rapid, but continued improvement may be seen for as long as 2 years.

Reversible cardiomyopathy in an infant with unrecognized congenital adrenal hyperplasia

We describe an infant who had a dilated cardiomyopathy and who was later found to have congenital adrenal hyperplasia. The cardiomyopathy resolved after replacement of glucocorticoid and mineralocorticoid. We believe that glucocorticoid deficiency may have played a direct role in the evolution of this cardiomyopathy.

Dilated cardiomyopathy in children: clinical course and prognosis

The clinical profile of 19 patients with dilated cardiomyopathy ages 2-18 years (mean 13.4 +/- 4 years) was reviewed to detect any factors that might be predictive for their survival. Follow-up range from 5 to 105 months (mean 39 +/- 33 months). Routine treatment consisted of digitalis and diuretics: 14 patients received antiarrhythmics, 6 received vasodilators, and 12 were managed with immunosuppression. There were 12 survivors and 7 nonsurvivors: The 1-year mortality was 21.2% and the 2-year mortality 35.8%. All deaths were within first 2 years. Of the 12 patients who survived 2 years, a significant improvement was noticed in 9. In 3 patients tachycardia-induced cardiomyopathy was diagnosed, and abolition of supraventricular tachycardia was followed by improvement and regression of cardiomegaly. Endomyocardial biopsy was performed in 16 patients. Four with a histologic diagnosis of active myocarditis survived, and in 3 of them a considerable improvement was noticed. Of the 12 patients with nonspecific histologic findings, 6 died (p < 0.05). There were no significant differences between survivors and nonsurvivors for any of the following parameters: incidence of severe heart failure (NYHA class III-IV) and severe ventricular arrhythmias (Lown class III-V), relative heart volume, echocardiographic left ventricular diastolic diameter and shortening fraction, and the hemodynamic parameters of cardiac index, left ventricular ejection fraction, left ventricular end-diastolic pressure, and left ventricular end-diastolic volume index.

Acute myocardial infarction complicating the clinical course of dilated cardiomyopathy in childhood

An acute myocardial infarction occurred in a 6-year-old child with dilated cardiomyopathy. This caused severe hemodynamic deterioration that led to a fatal outcome. Autopsy revealed diffuse myocardial atrophy without cell infiltrate, normal epicardial coronary arteries, and a massive healed anteroapical infarction. Coronary embolism or spasm could not be ruled out as the cause of the infarction.

Prognostic features of children with idiopathic dilated cardiomyopathy

The presenting features and long-term outcome of 39 children (median age 6.5 months, range 1 day to 16 years) with idiopathic dilated cardiomyopathy (IDC) were reviewed to help determine the appropriate management of these patients. Four outcome groups were identified: those who died, improved, had IDC resolved or received transplants. Presenting clinical features of age, sex, race, congestive heart failure, cardiomegaly, and degree of systolic ventricular dysfunction did not predict final outcome. Left ventricular hypertrophy on the electrocardiogram was seen significantly more often in children who improved than in those who died or in whom IDC resolved (p = 0.002). A rhythm disturbance was also seen more often in those who died than in those who survived (p = 0.025). Of 36 patients treated medically, 12 (33%) died, 15 (42%) improved and 9 (25%) resolved. Eighteen of 26 (69%) patients presenting at age less than or equal to 2 years survived, whereas 6 of 10 patients greater than 2 years survived. There were no differences based on age at presentation, in the time to death or time of follow-up. Three patients received orthotopic heart transplants, 1 of whom died from graft failure. Thus, no clinical feature including age at presentation consistently predicts ultimate outcome in children with IDC.

Cardiomyopathy in children in Ahmedabad

A clinical study and follow up of 20 children with cardiomyopathies upto age of 16 years are presented. The DCM was most common variety followed by RCM and HCM in pediatric age group. SHMD presenting with cardiomyopathy were common in infancy and early childhood. Cardiomyopathies presented most frequently between 2-5 years and 10-16 years age group with DCM having almost equal distribution. Clinical presentation of various types is described, despite of vigorous decongestive and vasodilator treatment in advanced cases, course was rapidly downhill and prognosis is poor in general.

Outcome of infants and children with dilated cardiomyopathy

A review of 81 infants and children with dilated, poorly contracting left ventricles without associated structural abnormalities was undertaken to identify risk factors for poor outcome, which could be used in selecting candidates for cardiac transplantation. Significant atrial or ventricular dysrhythmias, or both, were detected on presentation or during follow-up in 24 patients. Arrhythmias were present in only 8 of 51 survivors (16%) but were detected in 16 of 30 patients (53%) who died (p less than 0.05). Patients dying suddenly were even more likely to have had documented dysrhythmias (8 of 11, p less than 0.05). Left ventricular shortening fraction was similar in survivors and nonsurvivors (14.9 +/- 1.0% vs 15.3 +/- 1.7%). Left ventricular end-diastolic pressure in 44 patients who had cardiac catheterization averaged 20.8 +/- 1.6 mm Hg. Left ventricular end-diastolic pressure was significantly higher in patients who died than in those who survived (29.5 +/- 2.2 vs 15.0 +/- 1.6 mm Hg, p less than 0.001). Analysis of actuarial survival revealed that mortality was highest during the first 6 months after presentation (19% mortality). Survival declined more gradually thereafter and was 70% at 2 years, 64% at 5 years and 52% after 11.5 years. Age at initial presentation did not have any significant impact on survival. However, left ventricular end-diastolic pressure greater than 25 torr was associated with a significantly increased mortality rate (p less than 0.05). Early cardiac transplantation should be considered in patients with markedly elevated left ventricular end-diastolic pressure or complex atrial or ventricular arrhythmias.

Clinical course of idiopathic dilated cardiomyopathy in children

Previous studies in adults with dilated cardiomyopathy suggest that the presence of arrhythmia, especially ventricular tachycardia, correlates with increased mortality. We performed a retrospective analysis of 63 children with idiopathic dilated cardiomyopathy to determine the prognostic significance of arrhythmias and other findings with respect to mortality. The mean age at diagnosis of the cardiomyopathy was 4.96 +/- 5.3 years. The overall mortality rate was 16% over a 10 year follow-up period. Persistent congestive heart failure and ST-T wave changes correlated with increased mortality (p less than 0.05). No other variables affected outcome. Arrhythmias were found in 46% of the patients; of the arrhythmias, 48% were atrial arrhythmias. Ventricular tachycardia was present in six patients. Death occurred in 4 (14%) of 29 patients with known arrhythmia; 1 of the 5 died suddenly. The remaining 6 deaths in the series occurred in the 34 patients without a documented arrhythmia. It is concluded that 1) arrhythmias are frequently seen in children with dilated cardiomyopathy but are not predictive of outcome; 2) sudden death in children with this disease is rare; and 3) persistent congestive heart failure portends a poor prognosis.

Natural history of dilated cardiomyopathy in children

To assess the natural history and potential risk factors in childhood dilated cardiomyopathy, we investigated 25 patients (ages 9.6 +/- 4.4 years) who presented after they were 2 years old. All patients had symptoms of congestive heart failure and reduced contractility with a dilated left ventricle at presentation. Two factors at presentation were significantly different between patients who died less than 1 year after the presentation (n = 14) and those who survived for more than 1 year (n = 9); cardiothoracic ratio (65.1% +/- 6.8% vs 57.1% +/- 6.1%, p less than 0.01) and left ventricular ejection fraction (31.3% +/- 7.0% vs 40.0% +/- 6.2%, p less than 0.05). Irrespective of intensive medical therapy, dilated cardiomyopathy in children had a poor prognosis; the actuarial survival rate was 41% at 1 year and 20% at 3 years. Other forms of therapy should be considered in the early stages of dilated cardiomyopathy in this high-risk group.

Nonimmunologic hydrops fetalis: an etiopathogenetic approach through the postmortem study of 59 patients

Aiming at increasing our understanding of the various causative factors of nonimmunologic hydrops fetalis (NIHF) and their pathogenetic mechanisms, we have reviewed 59 cases of this condition from a total number of 4,175 pediatric post-mortem studies performed at the Department of Pathology of the Hospital La Paz from 1967 to 1987. We found eight cases (13.5%) without clinical, biochemical, or post-mortem findings justifying the development of hydrops fetalis, seven cases (12%) associated with certain pathologic findings that by themselves do not explain the development of hydrops and, finally, 44 cases (74.5%) in whom pathological findings may explain the development of the condition. Notwithstanding the etiological diversity of this last group, in 31 of these cases (70%), some common pathogenetic features may be recognized, basically a failure of the right ventricle of the heart in the fetus or newborn, due to a primary heart condition, to intracardiac tumors, or to obstructive phenomena at the level of the right venous drainage. In our opinion, whenever NIHF is diagnosed or suspected, causes of right cardiovascular failure should be investigated, since about 50% of all cases seem to be due to this pathogenetic mechanism.