Combined immunosuppression for the treatment of idiopathic giant cell myocarditis

Giant cell myocarditis (GCM) is a rare and frequently fatal disorder with n o proven treatment. Case reports and data from a rat model of GCM suggest t hat immunosuppressive therapy directed against T lymphocytes may have clini cal benefit. We describe a 47-year-old man with severe acute heart failure due to GCM in whom the left ventricular ejection fraction normalized and th e myocardial inflammatory infiltrate resolved rapidly after treatment with muromonab-CD3, cyclosporine, azathioprine, and corticosteroids, Three previ ously published cases with less impressive responses to treatment including muromonab-CD3 and a critical review of the published data on immunosuppres sive therapy are included in this report. The response to immunosuppressive therapy is highly variable, and direct comparisons between immunosuppressi ve regimens do not exist. Therefore, despite individual reports of dramatic improvement after immunosuppressive treatment, firm conclusions cannot be made about the benefit of immunosuppression for GCM. The benefits of immuno suppressive therapy must be confirmed in a prospective, randomized trial.