High-dose immunoglobulin G therapy for fulminant myocarditis

The knowns and unknowns of cardiac autoimmunity in viral myocarditis

Myocarditis can result from various infectious and non-infectious causes that can lead to dilated cardiomyopathy (DCM) and heart failure. Among the infectious causes, viruses are commonly suspected. But the challenge is our inability to demonstrate infectious viral particles during clinical presentations, partly because by that point, the viruses would have damaged the tissues and be cleared by the immune system. Therefore, viral signatures such as viral nucleic acids and virus-reactive antibodies may be the only readouts pointing to viruses as potential primary triggers of DCM. Thus, it becomes hard to explain persistent inflammatory infiltrates that might occur in individuals affected with chronic myocarditis/DCM manifesting myocardial dysfunctions. In these circumstances, autoimmunity is suspected, and antibodies to various autoantigens have been demonstrated, suggesting that immune therapies to suppress the autoimmune responses may be necessary. From this perspective, we endeavoured to determine whether or not the known viral causes are associated with development of autoimmune responses to cardiac antigens that include both cardiotropic and non-cardiotropic viruses. If so, what their nature and significance are in developing chronic myocarditis resulting from viruses as primary triggers.

Effect of Acute Immunosuppression on Left Ventricular Recovery and Mortality in Fulminant Viral Myocarditis: A Case Series and Review of Literature

Background

Fulminant viral myocarditis (FVM) is a rare cause of cardiogenic shock associated with high morbidity and mortality rates. An inappropriately activated immune system results in severe myocardial inflammation. Acute immunosuppressive therapy for FVM therefore gained in popularity and was described in numerous retrospective studies.

Methods

We conducted an extensive review of the literature and compared it with our single-centre retrospective review of all cases of FVM from 2009-2019 to evaluate the possible effect of acute immunosuppression with intravenous immunoglobulins and/or high dose corticosteroids in patients with FVM.

Results

We report on 17 patients with a mean age of 46 ± 15 years with a mean left ventricular ejection fraction (LVEF) of 15 ± 9% at admission. Fourteen (82%) of our patients had acute LVEF recovery to ≥ 45% after a mean time from immunosuppression of 74 ± 49 hours (3.1 days). Extracorporeal membrane oxygenation (ECMO) was required in 35% (6/17) of our patients for an average support of 126 ± 37 hours. Overall mortality was 12% (2/17). No patient needed a long-term left ventricular assist device or heart transplant. All surviving patients achieved complete long-term LVEF recovery.

Conclusions

Our cohort of 17 severely ill patients received acute immunosuppressive therapy and showed a rapid LVEF recovery, short duration of ECMO support, and low mortality rate. Our suggested scheme of investigation and treatment is presented. These results bring more cases of successfully treated FVM with immunosuppression and ECMO to the literature, which might stimulate further prospective trials or a registry.

Intravenous immunoglobulin for presumed viral myocarditis in children and adults

BACKGROUND

This is an update of a previous review. Case reports and case series have described dramatic responses to intravenous immunoglobulin (IVIG) in people with presumed viral myocarditis, and its administration has become commonplace.

OBJECTIVES

The primary objective of this review was to compare event-free (death, requirement for a cardiac transplant, or placement of a left ventricular assist device) or overall (death) survival of adults and children with presumed viral myocarditis treated with IVIG versus those who did not receive IVIG. A secondary objective was to determine if a group of patients with presumed viral myocarditis could be identified (on the basis of age, duration of symptoms, acuity of onset of symptoms, cardiac function at presentation, virological results, or the presence or absence of histological evidence of acute myocarditis on cardiac biopsy in patients in whom a biopsy was performed) who would be the most likely to benefit from IVIG.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, DARE, CINAHL, Web of Science Core Collection, and LILACS in July 2019, and two trial registries in November 2019. We contacted authors of trials and checked reference lists of relevant papers. We applied no language restrictions.

SELECTION CRITERIA

We included studies if (1) participants had a clinical diagnosis of acute myocarditis with a left ventricular ejection fraction (LVEF) ≤ 0.45, left ventricular end-diastolic diameter (LVEDD) > 2 standard deviations (SDs) above the norm, or a left ventricular shortening fraction (LVSF) > 2 SDs below the mean, with duration of cardiac symptoms < 6 months; (2) participants had no evidence of non-infectious or bacterial cardiac disease; and (3) participants were randomly assigned to receive at least 1 g/kg of IVIG versus no IVIG or placebo. We excluded studies if (1) participants had received immunosuppression before outcome assessment; or (2) onset of myocarditis was reported to have occurred < 6 months postpartum.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the search results and extracted data. We assessed risk of bias with the Cochrane 'Risk of bias' tool. We conducted meta-analysis for two outcomes (overall survival and improvement in LVEF) with two adult trials. Other meta-analyses were not possible because only three relevant trials were included, and researchers analysed markedly different populations and used different outcome measures.

MAIN RESULTS

In this update we added two trials to the two previously included trials. A quasi-randomised trial was previously included due to a paucity of evidence from randomised trials; however, with the addition of two new randomised trials, it was removed from this update. For two adult trials, the overall risk of bias was unclear with very low-certainty evidence for all outcomes. The first trial studied 62 adults with recent-onset dilated cardiomyopathy randomly assigned to receive IVIG or an equivalent volume of 0.1% albumin in a blinded fashion. The effect on event-free survival between groups was uncertain (risk ratio (RR) of any event 1.76, 95% confidence interval (CI) 0.48 to 6.40). The second trial studied 41 adults with acute myocarditis randomised to either high-dose IVIG (1 to 2 g/kg over two days) or no treatment. The IVIG group reported greater survival time after 60 days (no raw data, P < 0.01), but the evidence is uncertain. We pooled the reported number of deaths in both trials, with no evidence of a difference between groups (RR 0.91, 95% CI 0.23 to 3.62, I2 = 31%, very low-certainty evidence). The evidence on the effect of IVIG treatment on LVEF (pooled mean difference (MD) -0.01, 95% CI -0.06 to 0.05) after 12 months and an unknown time frame is uncertain. The results for functional capacity, assessed by peak oxygen consumption at 12 months, were uncertain (MD -0.80, 95% CI -4.57 to 2.97). The results for infusion-related side effects were also uncertain due to a very large CI (RR 20.29, 95% CI 1.25 to 329.93). Lastly, there was uncertain evidence addressing failure to attain complete recovery (RR 0.46, 95% CI 0.19 to 1.14).  Evidence for improvement in LVEDD, left ventricular shortening fraction, and hospitalisation status in adults was not reported.  In the single included paediatric trial, the overall risk of bias was low with very low-certainty evidence for all outcomes. The trial included 86 children in Egypt presenting with acute myocarditis. Children were randomly assigned to 1 g/kg IVIG daily for two consecutive days or placebo followed by echocardiography one and six months post randomisation for recording of LVEDD and LVSF. The evidence for overall survival after six months was uncertain (risk of death RR 0.48, 95% CI 0.20 to 1.15). The evidence was also uncertain for improvement in LVEDD and LVSF after six months (LVEDD MD -4.00, 95% CI -9.52 to 1.52; LVSF no raw data).  Evidence for improvement in LVEF, functional capacity, side effects, complete recovery, and hospitalisation status in children was not reported.  AUTHORS' CONCLUSIONS: Evidence from two trials of very low certainty and with unclear risk of bias provides contradictory evidence on the use of IVIG in the treatment of adults with presumed viral myocarditis. One trial reported that use of IVIG results in longer survival time after 60 days, whilst the other trial found that IVIG does not provide an appreciable benefit. The evidence of a difference in event-free or overall survival, LVEDD, or LVSF is of very low certainty in a single paediatric trial with a low risk of bias. Until higher-quality studies with low risk of bias and larger sample sizes have demonstrated benefit in a particular group of patients, the evidence for treatment with IVIG for presumed viral myocarditis is uncertain. Further studies of the pathophysiology of myocarditis would lead to improved diagnostic criteria, which would facilitate future research.

Treatment options in myocarditis and inflammatory cardiomyopathy : Focus on i. v. immunoglobulins

For myocarditis and inflammatory cardiomyopathy, an etiologically driven treatment is today the best option beyond heart failure therapy. Prerequisites for this are noninvasive and invasive biomarkers including endomyocardial biopsy and polymerase chain reaction on cardiotropic agents. Imaging by Doppler echocardiography and cardiac magnetic resonance imaging as well as cardiac biomarkers such as C‑reactive protein, N‑terminal pro-B-type natriuretic peptide , and troponins can contribute to the clinical work-up of the syndrome but not toward elucidating the underlying cause or pathogenetic process. This review summarizes the phases and clinical features of myocarditis and gives an up-to-date short overview of the current treatment options starting with heart failure and antiarrhythmic therapy. Although inflammation in myocardial disease can resolve spontaneously, often specific treatment directed against the causative agent is required. For fulminant, acute, and chronic autoreactive myocarditis, immunosuppressive treatment has proven to be beneficial in the TIMIC and ESETCID trials; for viral cardiomyopathy and myocarditis, intravenous immunoglobulin IgG subtype and polyvalent intravenous immunoglobulins IgG, IgA, and IgM can frequently resolve inflammation. However, despite the elimination of inflammation, the eradication of parvovirus B19 and human herpesvirus-6 is still a challenge, for which ivIg treatment can become a future key player.

Cardio-Immunology of Myocarditis: Focus on Immune Mechanisms and Treatment Options

Myocarditis and inflammatory cardiomyopathy are syndromes, not aetiological disease entities. From animal models of cardiac inflammation we have detailed insight of the strain specific immune reactions based on the genetic background of the animal and the infectiosity of the virus. Innate and adaptive immunity also react in man. An aetiological diagnosis of a viral vs. a non-viral cause is possible by endomyocardial biopsy with histology, immunohistology and PCR for microbial agents. This review deals with the different etiologies of myocarditis and inflammatory cardiomyopathy on the basis of the genetic background and the predisposition for inflammation. It analyses the epidemiologic shift in cardiotropic viral agents in the last 30 years. Based on the understanding of the interaction between infection and the players of the innate and adaptive immune system it summarizes pathogenetic phases and clinical faces of myocarditis. It gives an up-to-date information on specific treatment options beyond symptomatic heart failure and antiarrhythmic therapy. Although inflammation can resolve spontaneously, specific treatment directed to the causative etiology is often required. For fulminant, acute, and chronic autoreactive myocarditis without viral persistence immunosuppressive treatment can be life-saving, for viral inflammatory cardiomyopathy ivIg treatment can resolve inflammation and often eradicate the virus.

Intravenous immunoglobulin for presumed viral myocarditis in children and adults

BACKGROUND

This is an update of a previous review. Case reports and case series have described dramatic responses to intravenous immunoglobulin (IVIG) in people with presumed viral myocarditis, and its administration has become commonplace.

OBJECTIVES

The primary objective of this review was to compare transplant-free survival of adults and children with presumed viral myocarditis treated with IVIG versus those who did not receive IVIG. A secondary objective was to determine if a group of patients with presumed viral myocarditis could be identified (on the basis of age, duration of symptoms, acuity of onset of symptoms, cardiac function at presentation, virological results or the presence or absence of histological evidence of acute myocarditis on cardiac biopsy in patients in whom a biopsy was performed) who would be the most likely to benefit from IVIG.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (2013, Issue 12 of 12), the Database of Abstracts of Reviews of Effects (DARE) (2013, Issue 4 of 4), MEDLINE (Ovid, 1946 to January Week 3 2014), EMBASE (Ovid, 1980 to Week 4 2014), the Cumulative Index to Nursing and Allied Health Literature (CINAHL) EBSCO, Web of Science (Thomson Reuters, 1970 to 24 January 2014), the Latin American and Caribbean Health Science Information Database (LILACS) (1982 to 30 January 2014), trials registries and conference proceedings. We contacted authors of trials and checked reference lists of relevant papers. We applied no language restrictions.

SELECTION CRITERIA

We included studies if (1) participants had a clinical diagnosis of acute myocarditis with a left ventricular ejection fraction (LVEF) ≤ 0.45, left ventricular end-diastolic diameter (LVEDD) > 2 standard deviations (SDs) above the norm or a shortening fraction (SF) > 2 SDs below the mean with duration of cardiac symptoms < 6 months; (2) participants had no evidence of non-infectious or bacterial cardiac disease; and (3) participants were randomly assigned to receive at least 1 g/kg of IVIG versus no IVIG or placebo. We excluded studies if (1) participants had received immunosuppression before outcome assessment; or (2) onset of myocarditis was reported to occur < 6 months post partum.

DATA COLLECTION AND ANALYSIS

Two review authors screened searches and extracted data independently. We assessed quality using the 'Risk of bias' tool. Meta-analysis was not possible because only two relevant studies were found, and researchers analysed markedly different populations.

MAIN RESULTS

In this update, review authors added one study to the study from the original review. The first relevant study involved 62 adults with recent-onset dilated cardiomyopathy randomly assigned to receive IVIG or an equivalent volume of 0.1% albumin in a blinded fashion. The overall risk of bias was unclear. The incidence of death or the requirement for cardiac transplant or placement of a left ventricular assist device was low in both groups (odds ratio (OR) for event-free survival 0.52, 95% confidence interval (CI) 0.12 to 2.30). Follow-up at six months and at 12 months showed equivalent improvement in LVEF (mean difference (MD) 0.00, 95% CI -0.07 to 0.07 at six months; MD 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 (MD -0.80, 95% CI -4.57 to 2.97). Infusion-related side effects were more common in the treated group, but all were reported to be mild (OR 30.16, 95% CI 1.69 to 539.42).The second study added at this update included 83 children in India with suspected viral encephalitis and myocarditis. The overall risk of bias was high. The odds ratio for event-free survival was 7.39 (95% CI 0.91 to 59.86). Follow-up occurred only until hospital discharge, and LVEF was 49.5% in the treated group versus 35.9% in the placebo group (risk difference 13.6%, 95% CI 5.1 to 22.1%; P value = 0.001).

AUTHORS' CONCLUSIONS

Evidence from one trial does not support the use of IVIG for the treatment of adults with presumed viral myocarditis. The only paediatric trial had high risk of bias but suggested that benefit may be seen in the select group of children beyond the neonatal period who have viral encephalitis with myocarditis. Until higher-quality studies have demonstrated benefit in a particular group of patients, IVIG for presumed viral myocarditis should not be provided as routine practice in any situation. Further studies of the pathophysiology of myocarditis would lead to improved diagnostic criteria, which would facilitate future research.

Use of intravenous immunoglobulin in critically ill patients

Intravenous immunoglobulin (IVIG) has been suggested for the treatment of many ailments due to its ability to modulate the immune system and to provide passive immunity to commonly circulating pathogens. Its use as primary and adjunctive therapy for the treatment of conditions affecting critically ill patients is an attractive option, especially when alternative therapy does not exist. The body of literature on the use of IVIG for the treatment of several serious conditions, including sepsis, toxic shock syndrome, acute myocarditis, Stevens-Johnson syndrome, toxic epidermal necrolysis, and H1N1 influenza, were reviewed. Despite advances in treatment of these conditions since they were first described, there remains a paucity of well-designed studies on the use of IVIG for their treatment. Therefore, the use of IVIG for treatment of these conditions remains controversial.

Intravenous immunoglobulin in the therapy of adult acute fulminant myocarditis: A retrospective study

Acute fulminant myocarditis (AFM) is a serious heart disease with limited treatment. This observational retrospective study aimed to investigate whether intravenous immunoglobulin (IVIG) was able to improve left ventricular function and reduce the episodes of arrhythmia in adult patients with AFM. The medical records of all patients with AFM who were admitted to the Critical Care Unit of Guangdong General Hospital (Guangzhou, China) between January 2001 and December 2010 were reviewed. A cohort of 58 patients was included in the study. Of these 58, 32 patients were treated with IVIG (400 mg/kg per day) for five days, while the remaining patients did not receive IVIG therapy. The patients who received IVIG therapy had a higher left ventricular ejection fraction (LVEF) and a reduced left ventricular end-diastolic diameter (LVDD) compared with the non-IVIG therapy patients four weeks subsequent to the treatment (P_LVEF=0.011 and P_LVDD=0.048). The post-treatment incidence of ventricular tachycardia/ventricular fibrillation (VT/VF) and atrioventricular block (AVB) was reduced in the patients who received IVIG therapy compared with the baseline values (P_VT/VF=0.025, P_AVB=0.003); however, no significant differences were observed in the non-IVIG therapy patients (P_VT/VF=0.564, P_AVB=0.083) following treatment. There were two mortalities in the IVIG therapy group and seven in the non-IVIG therapy group (P=0.072). This retrospective study suggested that the use of IVIG for the treatment of AFM may be associated with improved left ventricular function and reduced episodes of fulminant arrhythmias.

Current treatment options in (peri)myocarditis and inflammatory cardiomyopathy

In inflammatory dilated cardiomyopathy and myocarditis there is--apart from heart failure and antiarrhythmic therapies--no alternative to an aetiologically driven specific treatment. Prerequisite are noninvasive and invasive biomarkers including endomyocardial biopsy and PCR on cardiotropic agents. This review deals with the different etiologies of myocarditis and inflammatory cardiomyopathy including the genetic background, the predisposition for heart failure and inflammation. It analyses the epidemiologic shift in pathogenetic agents in the last 20 years, the role of innate and aquired immunity including the T- and B-cell driven immune responses. The phases and clinical faces of myocarditis are summarized. Up-to-date information on current treatment options starting with heart failure and antiarrhythmic therapy are provided. Although inflammation can resolve spontaneously, specific treatment directed to the causative aetiology is often required. For fulminant, acute and chronic autoreactive myocarditis immunosuppressive treatment is beneficial, while for viral cardiomyopathy and myocarditis ivIg can resolve inflammation and is as successful as interferon therapy in enteroviral and adenoviral myocarditis. For Parvo B19 and HHV6 myocarditis eradication of the virus is still a problem by any of these treatment options. Finally, the potential of stem cell therapy has to be tested in future trials. In virus-negative, autoreactive perimyocardial disease a locoregional approach with intrapericardial instillation of high local doses of triamcinolone acetate has been shown to be highly efficient and with few systemic side-effects.

The evolving approach to paediatric myocarditis: a review of the current literature

Paediatric myocarditis remains challenging from the perspectives of diagnosis and management. Multiple aetiologies exist and the majority of cases appear to be related to viral illnesses. Enteroviruses are believed to be the most common cause, although cases related to adenovirus may be more frequent than suspected. The clinical presentation is extremely varied, ranging from asymptomatic to sudden unexpected death. A high index of suspicion is crucial. There is emerging evidence to support investigations such as serum N-terminal B-type natriuretic peptide levels, as well as cardiac magnetic resonance imaging as adjuncts to the clinical diagnosis. In the future, these may reduce the necessity for invasive methods, such as endomyocardial biopsy, which remain the gold standard. Management generally includes supportive care, consisting of cardiac failure medical management, with the potential for mechanical support and cardiac transplantation. Treatments aimed at immunosuppression remain controversial. The paediatric literature is extremely limited with no conclusive evidence to support or refute these strategies. This article summarises the current literature regarding aetiology, clinical presentation, diagnosis, and management of myocarditis in paediatric patients.

[Treatment of progressive heart failure: pharmacotherapy, resynchronization (CRT), surgery]

The treatment of progressive and terminal heart failure follows the principle of causative therapy. Therefore, etiology and pathophysiology of the underlying disease and its hemodynamic conditions are indispensable. This applies to coronary artery disease, hypertension, valvular heart disease, the cardiomyopathies with and without inflammation, and microbial persistence similarly. The classic treatment algorithms both in heart failure with and without reduced ejection fraction are based on measures onloading the heart (angiotensin-converting enzyme inhibitors, angiotensin antagonists, beta-blockers, diuretics) and on antiarrhythmics and anticoagulation, when needed. Device therapy for cardiac resynchronization in left bundle branch block and permanent stimulation therapy may contribute to the hemodynamic benefit. ICD (implantable cardioverter defibrillator) therapy prevents sudden cardiac death, which is often associated with progressive heart failure. Heart transplantation and left ventricular assist devices are final options in the treatment repertoire of terminal heart failure.

Intravenous immunoglobulin treatment for acute fulminant inflammatory cardiomyopathy: series of six patients and review of literature

BACKGROUND

Although an autoimmune mechanism has been postulated for myocarditis and acute-onset inflammatory dilated cardiomyopathy (DCM), immunomodulatory treatment strategies are still under investigation.

METHODS AND RESULTS

The clinical data of six patients with acute inflammatory DCM referred for evaluation for possible heart transplantation were reviewed. All patients were admitted with acute congestive heart failure and severely impaired left ventricular (LV) function and were treated with high-dose (2 g/kg) intravenous immunoglobulin (IVIG). The diagnosis of acute inflammatory DCM was based on recent onset of congestive heart failure (New York Heart Association functional class III or IV) with severely depressed LV ejection fraction ([LVEF] 30% or lower) occurring shortly after viral-like illness. All patients had inflammation on endomyocardial biopsy or elevated cardiac enzymes, as well as a normal coronary angiogram. All patients were in New York Heart Association class I or II at the time of hospital discharge. The mean LVEF improved from 21.7+/-7.5% at baseline to 50.3+/-8.6% at discharge (P=0.005). Four patients had complete recovery (LVEF 50% or higher) and two patients had partial LV recovery. Patients were followed for a median 13.2 months (range two to 24 months) and had a mean LVEF of 53+/-6% (P not significant versus LVEF at discharge).

CONCLUSIONS

Therapy with intravenous high-dose IVIG may be a potentially useful treatment in selected patients if given early in the course of acute fulminant inflammatory DCM. A randomized, prospective trial is warranted to prove the real benefit of IVIG in this patient population.

A systematic review of intravenous gamma globulin for therapy of acute myocarditis

Background

Intravenous gamma globulin (IVGG) is commonly used in the management of acute myocarditis. The objective of this study was to systematically review the literature evaluating this practice.

Methods

We conducted a comprehensive search (electronic databases, trials registries, conference proceedings, reference lists, contact with authors) to identify studies evaluating the use of IVGG in adults and children with a clinical or histologically proven diagnosis of myocarditis of possible viral etiology and symptoms of less than six months duration. Two reviewers independently screened the searches, applied inclusion criteria, and graded the evidence.

Results

Results were described qualitatively; data were not pooled because only one randomized controlled trial (RCT) with 62 patients was identified. The RCT showed no benefit with respect to cardiac function, functional outcome, or event-free survival. A small, uncontrolled trial (n = 10) showed significant improvement in LVEF from a mean of 24% to 41% 12 months after IVGG in nine survivors. A retrospective cohort study of pediatric patients showed improvement in cardiac function and a trend towards improved survival in patients receiving IVGG (n = 21) versus historic controls (n = 25). Ten case reports and two case series (total n = 21) described improvement in cardiac function after administration of IVGG; two case reports showed no benefit of IVGG. One case of hemolytic anemia was attributed to IVGG.

Conclusion

There is insufficient data from methodologically strong studies to recommend routine use of IVGG for acute myocarditis. Future randomized studies that take into account the etiology of acute myocarditis will be required to determine the efficacy of IVGG.

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.

Efficacy of intravenous immunoglobulin in chronic idiopathic pericarditis: report of four cases

Human intravenous immunoglobulins (hIVIgs) are used in two broad categories of diseases: immunodeficiency and autoimmunity. Among the immune-mediated diseases hIVIgs are of benefit in idiopathic thrombocytopenic purpura, autoimmune hemolytic anemia, and dermatomyositis. Chronic idiopathic pericarditis (CIP) is a chronic disease of unknown origin characterized by recurrent episodes of pericardial inflammation. The cause of the recurrence is unknown, although in some cases it may be traced to a viral infection and to the presence of antimyocardial antibodies. Since a viral infection can induce an autoimmune process through a mechanism of molecular mimicry, and since the optimal therapy for prevention of the recurrences has not been established, we reasoned that treatment with hIVIgs could be beneficial in our patients unresponsive to previous immunosuppressive therapies. We describe four patients affected by CIP treated with monthly high-dose hIVIgs (0.4 g/kg daily for 5 consecutive days) for five times followed by administration every 2 months. Three of the four patients could permanently discontinue steroid therapy and are still in remission after years of follow-up. Our experience suggests that hIVIgs therapy may be a useful and safe treatment for CIP in steroid-dependent patients.

Successful immunoglobulin treatment for fulminant myocarditis and serial analysis of serum thioredoxin: a case report

A 31-year-old woman suspected to have acute myocarditis was admitted to hospital and was managed with intra-aortic balloon pumping and a percutaneous cardiopulmonary support system because of sustained ventricular tachycardia. After immunoglobulin treatment, cardiac function and systematic inflammation were improved. The left ventricular endomyocardial biopsy revealed massive necrosis and degeneration of myocardial cells, and extensive infiltration of inflammatory cells. The clinicopathology of this patient was thought to be fulminant myocarditis. Serial serum thioredoxin (TRX) analysis showed that the serum level was high during the acute phase, and decreased during the chronic phase. Immunohistochemistry for TRX in the biopsy samples showed that inflammatory cells and cardiomyocytes were positively stained.

Idiopathic Cardiomyopathy

Idiopathic cardiomyopathy is a very common cause of heart failure today. It is a diagnosis of exclusion, and careful attention should be paid to the patient history to exclude all other causes. ACE inhibitors have become the first line therapy for all classes of left ventricular dysfunction. Doses of all therapeutic drugs for CHF should be up-titrated to maximum targeted dosages. New agents are being developed that offer increasing hope for therapies that will alter the natural history of heart failure.