Treatment of inflammatory dilated cardiomyopathy and (peri)myocarditis with immunosuppression and i.v. immunoglobulins.

OBJECTIVES

Treatment objectives in inflammatory dilated cardiomyopathy (DCMi), myocarditis (M) and peri(myo)carditis are 1) the elimination of inflammatory cells from the myocardium and pericardium, 2) the elimination or (second best) mitigation of B-cell products such as antibodies and immuncomplexes directed against cardiac epitopes such as sarcolemmal, fibrillary and mitochondrial epitopes, and 3) the eradication of the causative viral or microbial agent, if present.

ANTIPHLOGISTIC TREATMENT

A "non-specific" anti-inflammatory treatment in peri(myo)carditis can be carried out with antiphlogistics (NSAIDs preferably colchicine 1-3 mg/d) independent from the presence of the infective agent. In larger virus and bacteria negative effusions we recommend intrapericardial instillation of cristalloid triamcinolon (Volon A) at a dose of 500 mg/m(2), which should be left in place to have a sustained effect over at least 4 weeks. This will effectively prevent recurrences particularly when colchicine is added over a period of at least 3-6 months. Taking into account the 2004 ESC task force recommendations on the management of pericardial diseases the treatment recommendation for NSAIDs and colchicine can be classified as level of evidence A, indication class I, for intrapericardial triamcinolon instillation as level of evidence B, indication class IIa.

IMMUNOSUPPRESSION

In (immuno)histologically validated autoreactive (virus negative) myocarditis and DCMi double-blind randomized trials are lacking to demonstrate the superiority of immunosuppression over conventional heart failure management. The only published randomized and double-blind immunosuppression treatment trial (American Myocarditis Treatment Trial) was underpowered and did not distinguish viral from non-viral disease. It showed neither benefit nor harm of a combination of cyclosporin and prednisone. A number of retrospective analyses of immunosuppression in myocarditis showed some benefit of surrogate parameters (ejection fraction, exercise tolerance) but improvement under conventional heart failure treatment cannot be ruled out completely as the main cause for amelioration. ESETCID (European Study on the Epidemiology and Treatment of Cardiac Inflammatory Disease) is a double-blind, randomized, placebo-controled three-armed trial with prednisolone and azathioprine for autoreactive (virus negative) DCMi, interferon alpha for enterovirus positive DCMi, high-dose immunoglobulin for cytomegalovirus and intermediate dose for adeno- and Parvo B19 DCMi. It has now randomized more than 120 patients to the different treatment arms. Its final result has still to be awaited.-Patients not willing to randomize in the trial were included in a registry follow-up, which shows improvement of hemodynamic parameters and elimination of the inflammation in the majority of patients. This is in concordance with several non-randomized trials. Since evidence is conflicting (level of evidence C, indication class IIb; if negative viral etiology is taken into consideration class IIa) treatment with immunosuppression cannot be generally recommended but should be further evaluated in doubleblind randomized clinical trials or at least in controlled trials and registries. This also applies to treatment with interferon for enteroviral or other viral infections in the heart.

IMMUNOADSORPTION

: The elimination of anticardiac antibodies, which have been associated with DCMi, is a currently discussed concept, which is supported by published registry data and a few very small controlled investigations but not by a randomized double-blind trial with clinical endpoints of relevance. In some studies immunoglobulins have been substituted, so that an additional immunomodulatory effect has to be taken into account. The current proof of concept can be ranked level of evidence C, indication class IIa only. An even more challenging and still more attractive hypothesis is that cardiac inflammation caused by specific circulating beta-adrenoceptor antibodies can be eradicated with the elimination of the beta-receptor antibody thus healing dilated cardiomyopathy. Application of this approach can be ranked level of evidence C, indication class IIb at present only. Therefore these two pathophysiologically attractive concepts have to await further validation by a double-blind, randomized clinical endpoint trial.

IMMUNOGLOBULIN TREATMENT

It has been shown that immunoglobulins have both an antiviral and an anti-inflammatory effect. They may suppress proinflammatory cytokines and reduce oxidative stress. HIGH-DOSE I.V.

IMMUNOGLOBULINS (IVIG): In biopsy proven CMVmyocarditis a controlled trial demonstrated eradication of inflammation and of the virus (level of evidence B, indication class IIa), which is in accordance with registry data and case reports. In suspected myocarditis (not biopsy proven, no viral etiology established or excluded) conflicting data exist with respect to the improvement of surrogate markers such as the ejection fraction under high-dose immunoglobulins. More evidence can be weighted in favour of a positive treatment effect (level of evidence B, indication class IIb). Importantly there were no detrimental effects of the ivIG reported in these trials. One has to consider the high costs of this treatment, however. A trial taking into account the different etiologies (different viruses assessed separately vs. non-viral/autoreactive vs. placebo) is still lacking. MODERATE-DOSE I.V.

IMMUNOGLOBULINS

Registry data support a positive effect of 20 g i.v. pentaglobin (IgG and IgM) in adenovirus positive myocarditis for clinical improvement, eradication of both the inflammation and the virus. In Parvo B19 myocarditis our own registry data indicate that clinical improvement can be noted, but only inflammation is successfully eliminated, whereas Parvo B19 persistence remains a problem in the majority of patients. In Parvo B19 associated DCMi therefore dose finding studies and randomized trials are needed.