Giant cell myocarditis responding to immunosuppressive therapy.

An unusual case of giant cell myocarditis presenting with cardiogenic shock that dramatically responded to conventional dose of steroids and azathioprine is reported. Cardiac recovery was rapid, complete (left ventricular ejection fraction rose to 55% from 10%), and was accompanied by the disappearance of the inflammatory infiltrates including giant cells in the control endomyocardial biopsy. Maintenance of the recovery at 16 months of follow-up on a low dose of azathioprine suggests that giant cell myocarditis might be a heterogeneous disease having either a negative untreatable trend necessitating cardiac transplantation, or a curable substrate responding to immunosuppressive drugs.