Long-term outcome of fulminant myocarditis as compared with acute (nonfulminant) myocarditis

Hepatocyte Growth Factor Ameliorates the Progression of Experimental Autoimmune Myocarditis

Hepatocyte growth factor (HGF) plays a role in cell protection, antiapoptosis, antifibrosis, and angiogenesis. However, the role of HGF in the immune system is not well defined. We examined the influence of HGF on T cells and the effects of HGF therapy in acute myocarditis. Lewis rats were immunized on day 0 with cardiac myosin to establish experimental autoimmune myocarditis (EAM). Human HGF gene with hemagglutinating virus of the Japan-envelope vector was injected directly into the myocardium on day 0 or on day 14 (two groups of treated rats). Rats were killed on day 21. Expression of c-Met/HGF receptor in splenocytes and myocardial infiltrating cells was confirmed by immunohistochemical staining or FACS analysis. Myocarditis-affected areas were smaller in the treated rats than in control rats. Cardiac function in the treated rats was markedly improved. An antigen-specific T cell proliferation assay was done with CD4-positive T cells isolated from control rats stimulated with cardiac myosin. HGF suppressed T cell proliferation and production of IFN-γ and increased production of IL-4 and IL-10 secreted from CD4-positive T cells in vitro. Additionally, TUNEL assay revealed that HGF reduced apoptosis in cardiomyocytes. HGF reduced the severity of EAM by inducing T helper 2 cytokines and suppressing apoptosis of cardiomyocytes. HGF has potential as a new therapy for myocarditis.

Diagnostic utility of tenascin-C for evaluation of the activity of human acute myocarditis

Tenascin-C (TN-C) is an extracellular matrix protein that is expressed transiently in close association with tissue remodelling in various body sites. In the heart, TN-C is only present during early stages of development, is not expressed in the normal adult, but reappears in pathological states. The purpose of this study was to analyse the expression of TN-C in myocardial tissue from myocarditis patients, and to evaluate the diagnostic value of immunostaining for TN-C in the assessment of inflammatory activity in biopsy specimens. A total of 113 biopsy specimens obtained from 32 patients with a clinical diagnosis of acute myocarditis were examined by immunohistochemistry and in situ hybridization for TN-C. The immunostaining was semi-quantified and compared with histological diagnosis according to the Dallas criteria. Furthermore, serial biopsies from 22 patients were taken during convalescence, and sequential changes in TN-C levels were analysed. Expression of TN-C was specifically detected in endomyocardial biopsy specimens from patients with active-stage inflammation, and disappeared in healed stages. The degree of expression of TN-C correlated with the severity of histological lesions. These data suggest that TN-C reflects disease activity in cases of human myocarditis. Immunostaining for TN-C could enhance the sensitivity and accuracy of diagnosis using biopsy specimens.

[Acute myocarditis: from chest pain to cardiogenic shock]

We report the observations of three patients with myocarditis. The first one with chest pain, the second one with a pseudo-infarct presentation and the third one with a cardiogenic shock. We discuss the different anatomo-clinical presentations of myocarditis, the diagnosis, the indications of endomyocardial biopsies and the prognosis of this pathology.

Risk factors for patients developing a fulminant course with acute myocarditis

BACKGROUND

A fulminant course can be difficult to predict at the onset of acute myocarditis, so the aim of the present study was to identify the predictive clinical symptoms/signs or laboratory findings.

METHODS AND RESULTS

Thirty-nine patients with acute lymphocytic myocarditis, excluding 8 who manifested shock at admission, were studied. The fulminant group was defined as 12 patients who developed shock after admission, requiring intraaortic balloon pumping or percutaneous cardiopulmonary support, and the non-fulminant group comprised the 27 patients without shock. Various parameters at admission were compared between the 2 groups, together with multiple logistic regression analysis, excluding 6 patients with partially missing values. In the fulminant group, C-reactive protein (7.0 +/- 7.0 vs 2.3 +/- 2.2 mg/dl, p<0.01) and creatine kinase (1,147 +/- 876 vs 594 +/- 568 IU/L, p<0.05) concentrations were higher, intraventricular conduction disturbances were more frequent (9/12 vs 7/27 patients, p<0.01) and the left ventricular ejection fraction was lower (40.7 +/- 13.9 vs 50.1 +/- 10.6%, p<0.05) than in the non-fulminant group. In the multiple logistic regression analysis model with the presence/absence of a fulminant course considered as the independent variable, and C-reactive protein, creatine kinase, intraventricular conduction disturbances, and left ventricular ejection fraction as dependent variables, a high-risk group (expected proportion of fulminant course > or = 0.5) and a low-risk group (<0.5) could be differentiated. A fulminant course occurred in 9/13 (69%) patients in the high-risk group, but in only 2/20 (10%) patients in the low risk group (p<0.001).

CONCLUSIONS

The risk of a fulminant course of acute myocarditis was high in patients with elevated C-reactive protein, and creatine kinase concentrations, decreased left ventricular ejection fraction, and intraventricular conduction disturbances at the time of admission.

Plasma concentrations of cytokines and neurohumoral factors in a case of fulminant myocarditis successfully treated with intravenous immunoglobulin and percutaneous cardiopulmonary support

A 53-year-old Japanese man with fulminant myocarditis was referred. Percutaneous cardiopulmonary support (PCPS) was introduced immediately and intravenous immunoglobulin (IVIG) therapy followed for 2 days. Cardiac function showed signs of recovery on the 4th hospital day and the patient was weaned from PCPS on the 7th hospital day. Creatine kinase-MB peaked at 12 h after admission and was 176 ng/ml. Endomyocardial biopsy showed active myocarditis. A marked increase of the neutralizing antibody titer suggested coxsackievirus B3 infection. Plasma concentrations of cytokines and neurohumoral factors were analyzed. Proinflammatory cytokines, such as interleukin (IL)-1beta, IL-6 and tumor necrosis factor (TNF-alpha), and anti-inflammatory cytokines, such as IL-1 receptor antagonist, soluble TNF receptor-1 and IL-10, were elevated on admission and all had decreased on the 7th hospital day. Brain natriuretic peptide and noradrenaline were already elevated upon admission (1,940 pg/ml and 4.6 ng/ml, respectively) and decreased thereafter. Although IVIG therapy under PCPS is a common treatment for fulminant myocarditis, the immunological response in vivo remains unclear. This case demonstrated suppression of serum cytokines after IVIG and PCPS treatment. Immunological parameters in those who have been treated with IVIG and PCPS and survived without complications are of great value for evaluation of the therapy. Further analysis with more cases in a multicenter study is necessary.

Intravenous immunoglobulin for presumed viral myocarditis in children and adults

BACKGROUND

Case reports and case series have described dramatic responses to IVIG in adults and children with presumed viral myocarditis. Administration of IVIG has become commonplace in the management of this condition.

OBJECTIVES

To compare the outcome of patients with presumed viral myocarditis treated with IVIG to patients who did not receive IVIG.

SEARCH STRATEGY

We searched CENTRAL (Issue 2, 2003), MEDLINE/PubMed (1966-2003), EMBASE (1988-2003), CINAHL (1982-2003), Web of Science (1975-2003), trials registries and conference proceedings. We contacted authors of trials and checked reference lists of relevant papers.

SELECTION CRITERIA

Studies were included if: (1) patients had a clinical diagnosis of acute myocarditis with either a left ventricular ejection fraction (LVEF) <= 0.45, LVEDD of >2 SDs above the norm, or a shortening fraction (SF) >2 SDs below the mean and the duration of cardiac symptoms was less than six months; (2) patients had no evidence of non-infectious or bacterial cardiac disease; and, (3) patients were randomised to receive at least 1 gm/kg of IVIG versus no IVIG or placebo. Studies were excluded if: (1) patients had received immunosuppression prior to outcome assessment; or, (2) onset of myocarditis was less than six months postpartum.

DATA COLLECTION AND ANALYSIS

Searches were screened and inclusion criteria applied independently by two reviewers. Quality was assessed by two reviewers using the Jadad scale and allocation concealment. Data were extracted independently by two reviewers. Meta-analysis was not possible because only one relevant study was found.

MAIN RESULTS

The relevant study involved 62 adults with acute myocarditis randomized to receive IVIG or an equivalent volume of 0.1% albumin in a blinded fashion. The incidence of death or requirement for cardiac transplant or placement of a left ventricular assist device was low in both groups (OR for event-free survival was 0.52 ,95% CI 0.12 to 2.30). Follow-up at six and 12 months showed equivalent improvement in LVEF (mean difference 0.00, 95% CI -0.07 to 0.07 at six months, mean difference 0.01, 95% CI -0.06 to 0.08 at 12 months). Functional capacity as assessed by peak oxygen consumption was equivalent in the two groups at 12 months (mean difference -0.80, 95% CI -4.57 to 2.97). Infusion-related side effects were more common in the treated group, but all appeared to be mild (OR 30.16, 95% CI 1.69 to 539.42).

AUTHORS' CONCLUSIONS

Evidence from one trial does not support the use of IVIG for the management of adults with presumed viral myocarditis. There are no randomized paediatric trials. Further studies of the pathophysiology of this entity would lead to improved diagnostic criteria which would facilitate future research.

Diagnostic approach to the patient with cardiomyopathy: whom to biopsy

The prevalence of congestive heart failure is increasing and the prognosis remains poor. Cardiomyopathy is one of the most frequent causes of congestive heart failure and is the most common etiology of patients submitted to heart transplant. Determination of the etiology of cardiomyopathy has both prognostic and therapeutic implications. History, physical examination, transthoracic echocardiogram, selected laboratory studies, and coronary angiography can often define the cause of cardiomyopathy, however, the etiology occasionally remains unknown despite this initial evaluation. The indications for endomyocardial biopsy (EMBx) in patients with cardiomyopathy and a negative initial evaluation remains uncertain. The search for Dallas histological criteria proven myocarditis prompted the performance of EMBx in patients with unexplained cardiomyopathy in hopes of identifying an etiology for which treatment would result in improvement in left ventricular function. The "negative" results of the Myocarditis Treatment Trial, with treated and controlled patients improving equally, dampened enthusiasm for this diagnostic procedure. However, our experience and recent evidence suggests that EMBx may be a valuable diagnostic modality and should be included in the evaluation of patients with initially unexplained cardiomyopathy.

Coxsackievirus group B type 3 infection upregulates expression of monocyte chemoattractant protein 1 in cardiac myocytes, which leads to enhanced migration of mononuclear cells in viral myocarditis

Coxsackievirus group B type 3 (CVB3) is an important cause of viral myocarditis. The infiltration of mononuclear cells into the myocardial tissue is one of the key events in viral myocarditis. Immediately after CVB3 infects the heart, the expression of chemokine(s) by infected myocardial cells may be the first trigger for inflammatory infiltration and immune response. However, it is unknown whether CVB3 can induce the chemokine expression in cardiac myocytes. Monocyte chemoattractant protein 1 (MCP-1) is a potent chemokine that stimulates the migration of mononuclear cells. The objective of the present study was to investigate the effect of CVB3 infection on MCP-1 expression in murine cardiac myocytes and the role of MCP-1 in migration of mononuclear cells in viral myocarditis. Our results showed that the expression of MCP-1 was significantly increased in cardiac myocytes after wild-type CVB3 infection in a time- and dose-dependent manner, which resulted in enhanced migration of mononuclear cells in mice with viral myocarditis. The migration of mononuclear cells was partially abolished by antibodies specific for MCP-1 in vivo and in vitro. Administration of anti-MCP-1 antibody prevented infiltration of mononuclear cells bearing the MCP-1 receptor CCR2 in mice with viral myocarditis. Infection by UV-irradiated CVB3 induced rapid and transient expression of MCP-1 in cardiac myocytes. In conclusion, our results indicate that CVB3 infection stimulates the expression of MCP-1 in myocardial cells, which subsequently leads to migration of mononuclear cells in viral myocarditis.

Fatal fulminant myocarditis caused by disseminated mucormycosis

Acute fulminant myocarditis is a critical clinical condition with sudden onset of severe congestive heart failure followed by severe haemodynamic deterioration. Instituting early left ventricular support may improve outcome and result in better long term survival. The case of an immunocompromised patient who developed acute fulminant myocarditis in the setting of disseminated mucormycosis is presented.

Serum levels of interleukin-10 on admission as a prognostic predictor of human fulminant myocarditis

OBJECTIVES

We assessed the significance of serum cytokine levels in patients with fulminant myocarditis.

BACKGROUND

Although many investigations have demonstrated the crucial role of cytokines in the development of myocarditis, it remains uncertain whether serum levels of cytokines enable one to predict the prognosis of human myocarditis, especially concerning cardiogenic shock (CS) requiring a mechanical cardiopulmonary support system (MCSS).

METHODS

We studied 22 consecutive patients with fulminant myocarditis and compared them with 15 patients with acute myocardial infarction (AMI) requiring MCSS. The patients with myocarditis were classified into three groups: eight patients with CS requiring MCSS on admission (group 1); six patients who unexpectedly lapsed into CS requiring MCSS more than two days after catecholamine had been initiated (group 2); and eight patients without MCSS (group 3). Furthermore, 14 patients with myocarditis requiring MCSS were divided into a fatal group (n = 5) and a survival group (n = 9). Biochemical markers, including serum cytokine levels and hemodynamic variables on admission, were analyzed.

RESULTS

Serum levels of interleukin (IL)-10 and tumor necrosis factor-alpha, but not other cytokines, were significantly higher in myocarditis than in AMI. Only serum levels of IL-10 were significantly higher in group 1 and 2 than in group 3 (49.1 +/- 37.5/20.7 +/- 17.6 pg/ml vs. 2.4 +/- 1.1 pg/ml; p = 0.0008/0.0012). Serum IL-10 levels were also significantly higher in the fatal group than in the survival group with myocarditis (74.0 +/- 27.0 pg/ml vs. 16.4 +/- 8.8 pg/ml; p = 0.003).

CONCLUSIONS

Serum IL-10 levels on admission enabled one to predict subsequent CS requiring MCSS and mortality of fulminant myocarditis patients.

Improved outcomes of pediatric dilated cardiomyopathy with utilization of heart transplantation

OBJECTIVES

We studied the outcomes of pediatric patients diagnosed with dilated cardiomyopathy (DCM) and their relation to epidemiologic and echocardiographic variables at the time of presentation.

BACKGROUND

The outcome of pediatric DCM patients ranges from recovery to a 50% to 60% chance of death within five years of diagnosis. The impact of heart transplantation and other emerging therapies on the outcomes of pediatric DCM patients is uncertain.

METHODS

We performed a retrospective study of the outcomes in 91 pediatric patients diagnosed with DCM from 1990 to 1999. Routine therapy included use of digoxin, diuretics, angiotensin-converting enzyme inhibitors, and heart transplantation.

RESULTS

At the time of last follow-up, 11 patients (12%) had died without transplantation; 20 (22%) underwent transplantation; 27 (30%) had persistent cardiomyopathy; and 33 (36%) had recovery of left ventricular systolic function. Overall actuarial one-year survival was 90%, and five-year survival was 83%. However, actuarial freedom from "heart death" (death or transplantation) was only 70% at one year and 58% at five years. Multivariate analysis found age <1 year (hazard ratio 7.1), age >12 years (hazard ratio 4.5), and female gender (hazard ratio 3.0) to be significantly associated with a greater risk of death or transplantation and a higher left ventricular shortening fraction at presentation (hazard ratio 0.92), with a slightly decreased risk of death or transplantation.

CONCLUSIONS

Pediatric DCM patients continue to have multiple outcomes, with recovery of left ventricular systolic function occurring most frequently. Utilization of heart transplantation has led to improved survival after the diagnosis of pediatric DCM.

Unexpected hazard of illegal immigration: Outbreak of viral myocarditis exacerbated by confinement and deprivation in a shipboard cargo container

We present a group of 18 illegal immigrant stowaways who arrived in a shipboard cargo container suffering from gastroenteritis, dehydration, and malnutrition and showing evidence of viral myocarditis in 3 of 4 fatalities. Our investigation included an evaluation of the 2-week ocean voyage, analysis of medical records and laboratory results of the survivors, autopsies on the decedents, and viral studies on their heart tissue. Of 3 stowaways who died shipboard, 2 showed lymphocytic myocarditis and 1 could not be evaluated histologically due to decomposition. A fourth stowaway died 4 months after arrival with dilated cardiomyopathy and lymphocytic myocarditis. Reverse-transcriptase polymerase chain reaction and nucleotide sequencing of viral isolates from the decedents' heart tissues demonstrated Coxsackie virus B3 genome. We believe that these cases represent an outbreak of viral myocarditis, exacerbated by acute dehydration and malnutrition, due to confinement within the shipping container. Our evidence indicates that close confinement promoted the spread of the virus, and nutritional deprivation increased the stowaways' vulnerability. Furthermore, our observations support the conclusion, based on experimental studies, that nutritionally induced oxidative stress increased the virulence of the etiologic viral agent. In summary, these cases represent a potential infectious disease hazard of illegal immigration.

Immunomodulatory treatment strategies in inflammatory cardiomyopathy: current status and future perspectives

Chronic autoimmunity and viral persistence constitute prognostic factors for adverse outcome in dilated cardiomyopathy patients. Inflammatory cardiomyopathy is a specific cardiomyopathy entity diagnosed in approximately 50% of dilated cardiopmyopathy patients by immunohistological quantification of immunocompetent infiltrates and cell adhesion molecule abundance. Patients with autoimmune inflammatory cardiomyopathy benefit from immunosuppressive treatment and immunoadsorption by improvement of left ventricular ejection fraction and heart failure symptoms, paralleled by a significant suppression of intramyocardial inflammation. However, dilated cardiomyopathy patients with viral persistence do not respond favorably to immunosuppression.

Short- and long-term mechanical ventricular assistance towards myocardial recovery

Long-term LVADs are primarily used as a bridge to transplantation because cardiac transplantation currently offers a better long-term outlook for most patients. Some patients will not get the opportunity for transplantation due to organ shortages and long waiting lists, however, and alternate care strategies must be considered. LVAD weaning and explantation may be an appropriate course of action for patients who have IDC and in whom transplantation is not the optimal therapy. The data demonstrate that LVAD weaning may be performed successfully in selected patients with IDC, and that transplantation may be delayed or avoided altogether; however, VAD weaning is not without its risks. Many of the patients have demonstrated recurrence of heart failure at various times after undergoing device removal. Through proper monitoring, most of these patients can be identified early enough to be relisted for transplantation, although some will require reinsertion of an LVAD while waiting. The critical steps in establishing a successful VAD weaning program are proper patient selection, ventricular unloading in the early stages, the institution of heart failure medications, frequent monitoring for ventricular recovery, and a period of ventricular retraining before explantation. In addition, the surgeons must be able to perform the explantation procedure with a low operative mortality. As experience with LVAD weaning and explantation grows, we may be able to better predict which patients may be successfully treated without resorting to transplantation. Explantation may eliminate, or safely delay, the need for cardiac transplantation. Although it is unlikely that these patients will be studied in a randomized fashion, the collection of accurate and complete data may allow us to establish a database that can answer many of today's questions.

Mortality in primary and secondary myocarditis

BACKGROUND

Lymphocytic myocarditis presents as a primary disorder or in association with a systemic disease. Whether primary and secondary myocarditis have the same prognosis is unknown.

METHODS

Patients (n = 171) referred to the Johns Hopkins Cardiomyopathy service from 1984 to 1998 with newly diagnosed cardiomyopathy were observed for an average of 5.9 years after an original diagnosis of biopsy-proven myocarditis or until reaching the end point of death. Giant-cell myocarditis was excluded from this study. Myocarditis was classified as secondary when a systemic disease was present at the time of presentation; otherwise, myocarditis was classified as primary. Survival rates among patients with primary and secondary myocarditis were compared with Kaplan-Meier analysis and Cox proportional hazard models incorporating clinical variables, including baseline hemodynamics and treatment with immunosuppressive therapy.

RESULTS

The mortality rate associated with secondary myocarditis varied substantially depending on the underlying systemic disorder. Peripartum myocarditis, when compared with idiopathic myocarditis, had a reduced mortality rate (relative hazard, 0.23 [0.06-0.98]; P <.05), which was attenuated after controlling for confounding variables (relative hazard, 0.62 [0.13-2.98]; P =.55). In contrast, human immunodeficiency virus myocarditis had a particularly poor prognosis (relative hazard, 6.70 [3.51-12.79]; P <.05), even after controlling for confounding variables. Myocarditis associated with systemic inflammatory disorders showed a trend toward increased mortality rate (relative hazard, 2.46 [0.65-9.38]; P =.19). For both primary and secondary myocarditis, advanced age and pulmonary hypertension were important clinical predictors of death.

CONCLUSIONS

The prognosis of patients with secondary myocarditis, when compared with patients with idiopathic myocarditis, seems most affected by the primary disease process.

Acute postoperative biventricular failure associated with antiphospholipid antibody syndrome

Antiphospholipid syndrome is probably the most common acquired hypercoagulable state, but information on perioperative management is sparse. Minor alterations in anticoagulant therapy, infection, or a surgical insult may trigger widespread thrombosis. The perioperative course of a 31-yr-old woman with primary anticardiolipin antiphospholipid antibody syndrome requiring a mitral valve replacement is described. Postoperatively, she developed acute global biventricular failure requiring extracorporeal membrane oxygenation support and plasmapheresis. The management of anticoagulation and cardiac surgery in this condition is reviewed.

Cardiovascular magnetic resonance assessment of human myocarditis: a comparison to histology and molecular pathology

BACKGROUND

Myocarditis can occasionally lead to sudden death and may progress to dilated cardiomyopathy in up to 10% of patients. Because the initial onset is difficult to recognize clinically and the diagnostic tools available are unsatisfactory, new strategies to diagnose myocarditis are needed.

METHODS AND RESULTS

Cardiovascular MR imaging (CMR) was performed in 32 patients who were diagnosed with myocarditis by clinical criteria. To determine whether CMR visualizes areas of active myocarditis, endomyocardial biopsy was taken from the region of contrast enhancement and submitted to histopathologic analysis. Follow-up was performed 3 month later. Contrast enhancement was present in 28 patients (88%) and was usually seen with one or several foci in the myocardium. Foci were most frequently located in the lateral free wall. In the 21 patients in whom biopsy was obtained from the region of contrast enhancement, histopathologic analysis revealed active myocarditis in 19 patients (parvovirus B19, n=12; human herpes virus type 6 [HHV 6], n=5). Conversely, in the remaining 11 patients, in whom biopsy could not be taken from the region of contrast enhancement, active myocarditis was found in one case only (HHV6). At follow-up, the area of contrast enhancement decreased from 9+/-11% to 3+/-4% of left ventricular mass as the left ventricular ejection fraction improved from 47+/-19% to 60+/-10%.

CONCLUSIONS

Contrast enhancement is a frequent finding in the clinical setting of suspected myocarditis and is associated with active inflammation defined by histopathology. Myocarditis occurs predominantly in the lateral free wall. Contrast CMR is a valuable tool for the evaluation and monitoring of inflammatory heart disease.

Long-Term Prognosis of Fulminant Myocarditis Rescued by Percutaneous Cardiopulmonary Support Device

BACKGROUND

The long-term prognosis and cardiac function of fulminant myocarditis treated with percutaneous cardiopulmonary support (PCPS) was compared with the outcome of those not treated with PCPS.

METHODS AND RESULTS

From 1991 to 2000, 14 patients with fulminant myocarditis (left ventricle ejection fraction (LVEF) < or =40%) were admitted to hospital. PCPS was necessary for treatment of shock in 8 (PCPS group), but not for the remaining 6 patients (non-PCPS group). In the PCPS group, 6 patients (75%) survived the critical phase and did not have any cardiac problems after discharge (range of follow-up period, 1.4-6.0 years). All patients in the non-PCPS group survived the acute phase; 1 patient had congestive heart failure 1.5 years after discharge, and another died from malignancy (follow-up period range, 2.2-9.4 years). Although the left ventricular ejection fraction (LVEF) of the PCPS group was significantly lower than that of the non-PCPS group in the acute phase, there was no significant difference in LVEF between the 2 groups in the chronic phase.

CONCLUSION

Patients who survive the acute phase crisis of acute myocarditis have a favorable long-term survival rate, whether or not mechanical support is used.

A formidable challenge: the diagnosis and treatment of viral myocarditis in children

It is generally well accepted that one third of patients with viral myocarditis experience a complete recovery of normal cardiac function, one third improve clinically but show residual cardiac dysfunction, and one third experience chronic heart failure and die or require heart transplantation. It is hoped that a better understanding of the underlying cause and pathogenesis of this disease will increase the number of patients who experience a complete recovery. New advances in both the diagnosis and treatment of viral myocarditis continue to enter clinical practice at a rapid pace, and it is likely that a genomic approach to the diagnostic evaluation and treatment of this disease will become possible in the near future. Viral myocarditis, however, will remain a significant diagnosticand therapeutic challenge to both physicians and scientists alike.

Assessment of myocardial recovery in a patient with acute myocarditis supported with a left ventricular assist device: a case report

Acute myocarditis may present with profound hemodynamic compromise; however, spontaneous resolution of the inflammatory process may occur in up to half of such patients. In patients with fulminant myocarditis, mechanical circulatory support may serve as a bridge to myocardial recovery. In this report we describe a 35-year-old man with acute myocarditis who required left ventricular assist device support as a bridge to recovery, and suggest a method for determining the suitability and timing of device explantation. A combination of echocardiography, right heart catheterization, exercise testing and serial endomyocardial biopsies was used to determine the resolution of myocarditis, recovery of myocardial function and timing for device explantation. Successful device explantation was performed after 37 days of device support. Further study is required to assess the role of ventricular assist devices in combination with immunosuppressive therapy in the management of fulminant myocarditis.

The problem of decompensated heart failure: nomenclature, classification, and risk stratification

Despite its high prevalence and significant rates of associated morbidity and mortality, the syndrome of decompensated heart failure remains poorly defined and vastly understudied. Few high-quality epidemiologic studies, randomized controlled trials, or published guidelines are available to guide the management of this complex disease. In addition, there is no consensus definition of the clinical problem that it presents, no agreed upon nomenclature to describe its clinical features, and no recognized classification scheme for its patient population; all of which has contributed to the lack of therapeutic development in this critical arena of cardiovascular disease. This review outlines the scope of the problem and proposes a system of nomenclature and classification sufficiently simple for general acceptance among clinicians while still encompassing the heterogeneity of the patient population. It also defines the current understanding of strategies for risk stratification in the setting of decompensated heart failure.

Epilogue: support devices for end stage heart failure

The present approach to circulatory assist/replacement devices is to use them as rescue for a patient in shock while awaiting transplant. In the next decade, the paradigm will shift to a more widespread use of such devices in patients without subsequent transplantation. Achievement of the ultimate goals of improved survival and quality of life for patients with advanced heart disease may depend on the strategic use of support devices more frequently than on the total replacement heart.

Myocarditis

Myocarditis and its sequela, dilated cardiomyopathy (DCM), cause substantial morbidity and mortality, especially in children and young adults. Physicians should include myocarditis in the differential diagnosis of all patients who have new symptoms of heart failure, arrhythmia, or chest pain syndromes of unclear cause, and should strongly consider performing endomyocardial biopsy (EMB) to establish the diagnosis. It may be necessary to perform multiple or serial biopsies to increase sensitivity. Patients with myocarditis and symptomatic heart failure, chest pain, or arrhythmias need hospitalization for evaluation and treatment. Patients with symptomatic left ventricular dysfunction should be treated with conventional heart failure therapy, including angiotensin-converting enzyme (ACE) inhibitors, digitalis, diuretics, and beta-blockers. Patients with arrhythmias or syncope may require electrophysiologic evaluation. In addition to conventional therapy, physicians should consider a course of immunosuppressive therapy in selected patients. The clinical course, response to therapy, and left ventricular function need close monitoring. Patients with myocarditis and rapidly progressive heart failure or cardiogenic shock should be referred early to an advanced heart failure center for implantation of a ventricular assist device and consideration for cardiac transplantation.

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.

Mechanical circulatory support for myocarditis: how much recovery should occur before device removal?

A 12-year-old girl with presumed myocarditis was supported with right and left ventricular assist devices for 68 days before device removal. During this time, the patient underwent echocardiography and right heart catheterization for evaluation of cardiac recovery. This case report serves as the basis for a discussion of criteria for deciding when to terminate mechanical circulatory support in a patient with recovery after acute myocarditis.

Surgical management of heart failure: an overview

Cardiac transplantation remains the gold standard of surgical therapies for advanced and end-stage heart failure. However, this very limited option trades one disease for another and can benefit only a small minority of patients. Heart failure is currently considered secondary to a structural increase in ventricular chamber volume or remodeling. Surgical therapies formerly contraindicated for the failing heart, as well as new therapies, can successfully affect ventricular remodeling and improve cardiac function. Surgical revascularization for patients with ejection fractions <20% is becoming common. Mitral valve repair is being explored, with surprisingly low operative mortality and encouraging intermediate results. Direct surgical approaches to restoring normal geometry and size to failing hearts, such as left ventricular reduction (Batista procedure), endoventricular patch plasty (Dor procedure), cardiomyoplasty, and prosthetic external constraints are under clinical investigation. Developments in mechanical assist therapy and a new generation of implantable intracorporeal assist devices are also discussed.

Innovative drug treatments for viral and autoimmune myocarditis

Myocarditis is a common cause of cardiomyopathy and is thought to account for 25% of all cases in humans. Unfortunately, the disease is difficult to detect clinically before a myopathic process ensues. Management of myocarditis-induced heart failure includes the standard regimen of diuretics, digoxin, angiotensin-converting enzyme inhibitors, angiotensin-II receptor blockers, and beta-adrenergic blockers. The management of myocarditis itself is dependent on the etiology of the illness. Treatments that are currently under investigation include immunosuppressants, nonsteroidal antiinflammatory agents, immunoglobulins, immunomodulation, antiadrenergics, calcium-channel blockers, angiotensin-converting enzyme inhibitors, nitric oxide inhibitors (e.g., aminoguanidine), and antivirals. Despite advances in treatment, more work needs to be done in the early detection of myocarditis. Additionally, better means need to be established for distinguishing between viral and noninfectious autoimmune forms of the disease, so that appropriate treatment can be instituted.

Extracorporeal membrane oxygenation in fulminant myocarditis complicating systemic lupus erythematosus

A 24-year-old woman with systemic lupus erythematosus developed cardiac failure and cardiogenic shock that failed to respond to both high-dose inotrope therapy and the insertion of an intra-aortic balloon pump. Circulatory support with extracorporeal membrane oxygenation facilitated cardiac recovery, either spontaneously or assisted by steroid therapy.

Pulmonary hypertension and risk of death in cardiomyopathy: patients with myocarditis are at higher risk

BACKGROUND

Pulmonary hypertension is a clinically useful predictor of death in patients with heart failure. Whether pulmonary hypertension has the same prognostic value among specific underlying causes of cardiomyopathy is unknown. Using a diverse cohort of cardiomyopathy patients, we tested the hypotheses that (1) elevated mean pulmonary arterial pressure is the most important hemodynamic predictor of death and (2) the prognostic value of mean pulmonary pressure varies among different cardiomyopathies.

METHODS AND RESULTS

Patients (n=1134) with new cardiomyopathy were prospectively assigned a specific diagnosis on the basis of clinical evaluation and endomyocardial biopsy. All patients underwent right heart catheterization at baseline and were followed for an average of 4.4 years. In multivariate Cox models that allowed for nonlinear relations between hemodynamics and death, mean systemic pressure (mSP) and mean pulmonary arterial pressure (mPA) emerged as the most important hemodynamic predictors of death. Moreover, there was a statistically significant positive interaction between mPA and the diagnosis of myocarditis. For each 5-mm Hg increase in baseline mSP, mortality rates decreased with relative hazard (RH) of 0.89 (0.86 to 0.92). For a 5-mm Hg increase in baseline mPA, mortality rates increased in patients who did not carry the diagnosis of myocarditis with RH 1.23 (1.17 to 1.29); among patients with myocarditis, mortality rates increased substantially with RH of 1.85 (1.50 to 2.29; P<0.001 for interaction).

CONCLUSIONS

Baseline mPA is particularly important for stratifying risk in myocarditis. These findings suggest that secondary pulmonary hypertension may have different biological features in myocarditis and that patients with pulmonary hypertension and myocarditis should be targeted for aggressive medical therapy.

Acute autoimmune cardiomyopathy in primary antiphospholipid antibody syndrome

We present a case of acute pulmonary oedema as the first presentation of autoimmune cardiomyopathy in primary antiphospholipid antibody syndrome in a patient who had no previous cardiac history. Five days of methylprednisolone at 500 mg/day followed by 100 mg/day for 10 days and then a weaning course of oral prednisone resulted in effective resolution of the acute diffuse cardiomyopathy. Her cardiac status became clinically and echocardiographically normal. We illustrate the effectiveness of immunosuppressive therapy as an adjunct to standard anti-failure measures in such presentations and we outline the association between antiphospholipid antibodies and cardiac dysfunction.

The role of right ventricular endomyocardial biopsy for idiopathic giant cell myocarditis

BACKGROUND

Idiopathic giant cell myocarditis (GCM) is an uncommon cause of cardiac failure distinguished clinically from lymphocytic myocarditis by rapidly progressive heart failure, arrhythmias, and heart block. Unlike fulminant lymphocytic myocarditis, patients with fulminant cardiac failure caused by GCM may respond to certain immunosuppressive agents; however, right ventricular endomyocardial biopsy (EMB) is infrequently used to establish the diagnosis partly because the sensitivity of EMB for GCM is unknown. The purpose of this study was to estimate the sensitivity of right ventricular EMB for GCM in a referral population.

METHODS AND RESULTS

Twenty subjects (of 63 total) in the Multicenter Giant Cell Myocarditis Registry underwent both right ventricular EMB and heart pathology (HRTP) evaluation from apical wedge, explantation, or autopsy. The false-negative rate of right ventricular EMB was defined as the ratio of negative EMB to positive HRTP results. Ten of the 20 subjects were women. The mean age was 38 years (range, 16-53 years). Twelve (60%) subjects had a positive EMB and positive HRTP confirming GCM. Three (15%) had a negative EMB and positive HRTP for GCM. Five had a positive EMB and negative HRTP evaluation for GCM. The resulting sensitivity of EMB for GCM was 80% (12/15) with a positive predictive value of 71%. Assuming the 5 subjects with a positive EMB and negative HRTP are true positives, the sensitivity improves to 85% (17/20). Predictors of negative HRTP after positive EMB were time from symptom onset to HRTP (P.006) and time from EMB to HRTP (P.03).

CONCLUSIONS

The sensitivity of right ventricular EMB is high in patients with GCM who have early disease presentation and a fulminant clinical course. Although these results may not apply to individuals with less aggressive disease, EMB may be used selectively to distinguish fulminant heart failure caused by GCM from other causes in which the prognosis may differ.

Successful explantation of a ventricular assist device following fulminant influenza type A-associated myocarditis

We report a case of fulminant myocarditis associated with refractory ventricular fibrillation following influenza A infection. Histologic examination was consistent with myocarditis and serology confirmed the viral etiology. The patient was supported with biventricular assist devices for 20 days during which her refractory ventricular fibrillation resolved spontaneously. This is the first documented case of resolution of prolonged ventricular fibrillation while on a ventricular assist device. This case suggests those patients with fulminant viral myocarditis and refractory ventricular arrhythmias may be supported successfully with ventricular assist devices until myocardial recovery takes place.

National survey of fulminant myocarditis in Japan: therapeutic guidelines and long-term prognosis of using percutaneous cardiopulmonary support for fulminant myocarditis (special report from a scientific committee)

Although fulminant myocarditis is known as a fatal disease, patients have been able to recover and return to normal life with the help of mechanical cardiopulmonary support. However, therapeutic guidelines for using percutaneous cardiopulmonary support (PCPS) for fulminant myocarditis have not been established, and the clinical course and long-term prognosis of such patients are still controversial issues. The present national survey considered the current situation of patients as the basis for proposing therapeutic guidelines. Thirty of 52 patients (57.7%) survived and returned to social life. Important factors concerning the prognosis were the severity and grade of cardiac and renal dysfunction, the adjusted support flow rate to enable recovery from circulatory failure, and prevention of circulatory disturbances of the legs and multiple organ failure directly associated with PCPS. With regard to the long-term prognosis of patients treated with PCPS, the readmission rate was 10%, the exacerbation rate was 3.3%, and mortality was 10% during the average follow-up period of 962 days. Optimal management of the mechanical cardiopulmonary support and curative treatment for the myocarditis further improve the outcome of this disease.

Fulminant myocarditis in polymyositis

Cardiac involvement in patients with polymyositis is usually asymptomatic and associated with a mild clinical course. A female patient with muscle weakness and cardiogenic shock, who was diagnosed with polymyositis and fulminant myocarditis, is described. A large amount of methylprednisolone, in addition to intra-aortic balloon pumping and percutaneous cardiopulmonary support, led to the recovery of her cardiac function. However, a massive cerebral embolism occurred and she died. Postmortem histopathological examination showed necroses of muscles and diffuse invasion of mononuclear cells in both the myocardium and the biceps muscle of her arm. Although the mechanism of cardiac dysfunction is not clear, immunosuppressive therapy was effective for fulminant myocarditis in the present case.

The group B coxsackieviruses and myocarditis

The six serotypes of the group B coxsackieviruses (CVB) are common human enteroviruses linked etiologically to inflammatory cardiomyopathies. This has been demonstrated by molecular detection of enteroviral RNA in human heart tissue, serologic associations with disease, and virus isolation from cases of fulminant myocarditis. The murine model of CVB-associated myocarditis has demonstrated that CVB can be attenuated through mutations at different genomic sites. Human CVB3 isolates demonstrate varying degrees of cardiovirulence in the murine model; one site of virulence determination has been mapped to domain II of the 5' non-translated region. The interplay of CVB replication and the immune response to that replication in the heart is a complex interaction determining the extent to which the virus replication is limited and the degree to which a pathogenic inflammation of cardiac muscle occurs. Studies of CVB3-induced myocarditis in murine strains lacking subsets of the immune system or genes regulating the immune response have demonstrated a pivotal role of the T cell response to the generation of myocarditis. While CVB are associated with 20-25% of cases of myocarditis or cardiomyopathy, the severity of the disease and the existence of attenuated strains shown to generate protective immunity in animal models indicates that vaccination against the CVBs would be valuable.

Early and long-term mortality of the clinical subtypes of myocarditis

The frequency of myocarditis and the prognosis for patients remains uncertain and, moreover, the clinical classification of myocarditis is controversial. From 1985 to 2000, 71 adult patients with clinically suspected myocarditis were admitted to 11 cardiovascular centers. Of these, 48 cases had histology proven myocarditis: 41 cases of lymphocytic myocarditis, 6 of giant cell myocarditis and 1 of eosinophilic myocarditis. Myocarditis was classified as acute (30 cases) or chronic (18 cases) according to the onset of the disease, and acute myocarditis was further categorized into common or fulminant type depending on whether or not patients required mechanical circulatory support in the management of heart failure (9 and 21 cases, respectively). Chronic myocarditis was divided into 3 subgroups: a persistent type lasting over 3 months after distinct onset (3 cases), a recurrent type (2 cases) and a latent form (13 cases). The early mortality of these 5 subtypes of myocarditis were acute common 22%, acute fluminant 43%, chronic persistent 33%, chronic recurrent 50%, and chronic latent 38%. The overall early mortality of all patients with myocarditis was 38% in spite of aggressive treatment during hospitalization. On the other hand, the long-term prognosis of patients with myocarditis was favorable; only 4 cases, who survived the active phase, died in the late phase: 1 had fulminant myocarditis and the other 3 had the chronic latent form. Thus, the early mortality of patients with myocarditis was very high regardless of the subtype, but if patients can survive the active phase, they have a favorable prognosis except with the chronic latent form.

Current role of endomyocardial biopsy in the management of dilated cardiomyopathy and myocarditis

Dilated cardiomyopathy is a common cause of congestive heart failure. Despite a thorough cardiovascular evaluation, a specific cause is frequently not found, and the disorder then is considered idiopathic. Endomyocardial biopsy (EMB) may yield diagnostic and prognostic information in patients with idiopathic dilated cardiomyopathy; however, the yield of useful information with this procedure among patients with heart failure is low, and the risks of occasional cardiac perforation and death further limit its use. Recent publications in the field of myocarditis and cardiomyopathy have renewed interest in the use of EMB in select patients to diagnose specific and potentially treatable myocarditides; however, the role of EMB in the work-up of patients with dilated cardiomyopathy is not well defined. In this article, we discuss the risks and utility of EMB in the management of patients with dilated cardiomyopathy and specific myocarditides.

Chronic active myocarditis following acute Bartonella henselae infection (cat scratch disease)

An association between Bartonella infection and myocardial inflammation has not been previously reported. We document a case of a healthy young man who developed chronic active myocarditis after infection with Bartonella henselae (cat scratch disease). He progressed to severe heart failure and underwent orthotopic heart transplantation. Bartonella henselae, therefore, should be included among the list of infectious agents associated with chronic active myocarditis.

Experimental autoimmune myocarditis in A/J mice is an interleukin-4-dependent disease with a Th2 phenotype

Myocarditis in humans is often associated with an autoimmune process in which cardiac myosin (CM) is a major autoantigen. Experimental autoimmune myocarditis (EAM) is induced in mice by immunization with CM. We found that EAM in A/J mice exhibits a Th2-like phenotype demonstrated by the histological picture of the heart lesions (eosinophils and giant cells) and by the humoral response (association of IgG1 response with disease and up-regulation of total IgE). Blocking interleukin (IL)-4 with anti-IL-4 monoclonal antibody (mAb) reduced the severity of EAM. This reduction in severity was associated with a shift from a Th2-like to a Th1-like phenotype represented by a reduction in CM-specific IgG1; an increase in CM-specific IgG2a; an abrogation of total IgE response; a decrease in IL-4, IL-5, and IL-13; as well as a dramatic increase in interferon (IFN)-gamma production in vitro. Based on the latter finding, we hypothesized that IFN-gamma limits disease. Indeed, IFN-gamma blockade with a mAb exacerbated disease. The ameliorating effect of IL-4 blockade was abrogated by co-administration of anti-IFN-gamma mAb. Thus, EAM represents a model of an organ-specific autoimmune disease associated with a Th2 phenotype, in which IL-4 promotes the disease and IFN-gamma limits it. Suppression of IFN-gamma represents at least one of the mechanisms by which IL-4 promotes EAM.

Acute myocarditis

Myocarditis is defined as inflammation of the myocardium accompanied by myocellular necrosis. Acute myocarditis must be considered in patients who present with recent onset of cardiac failure or arrhythmia. Often there is a history of an antecedent flu-like illness. Fulminant myocarditis is a distinct entity characterized by sudden onset of severe congestive heart failure or cardiogenic shock, usually following a flu-like illness. Giant cell myocarditis is a rare, frequently fatal disorder of unknown origin characterized by presence of giant cell inflammatory infiltrate in the myocardium. In recent years we have made good progress in understanding the causes, pathogenesis, natural history, diagnosis, and treatment of myocarditis. However, our knowledge is still far from complete. New information that extends our understanding of myocarditis is being reported constantly. This review summarizes recent advances in myocarditis, with an emphasis on the literature during the last year.

Nonpharmacologic treatment of acute heart failure

Acute heart failure is unusual in the pediatric population, but in many situations it justifies aggressive therapy. For example, children with lymphocytic myocarditis have an overall survival rate of nearly 90%, with complete myocardial recovery for the majority. Pharmacologic agents traditionally have been the mainstay of medical therapy for acute heart failure, but, in recent years, there has been increasing interest in using measures that reduce the myocardial workload. This article highlights nonpharmacologic approaches to the management of severe heart failure in the critically ill child. It also concentrates on physiologic approaches that address the balance between oxygen demand and delivery; the manipulation of cardiopulmonary interactions to optimize ventricular function; and the use of mechanical circulatory support as a method of achieving ultimate myocardial rest.