A model of myocarditis in humans.

In this issue of Circulation, Midei and colleagues1 from The Johns Hopkins University report a high incidence of myocarditis in women with postpartum congestive heart failure. Myocarditis was first convincingly documented to be a cause of peripartum cardiomyopathy in 1982 by Melvin et a12 at King's College Hospital in London through use of premortem transvenous endomyocardial biopsy. Since then, two other groups have reported larger series of 113 and 144 subjects in whom endomyocardial biopsy revealed incidences of myocarditis of 45% and 29%, respectively. The 78% incidence in the Johns Hopkins study is the highest rate reported in a series of this size. The Hopkins series may be atypical in other respects. Most investigators have noted a marked preponderance of women over 30 years of age (only half of the patients were over 30 years of age in the Hopkins study) and of multipara (only 60% in the