A 44 year old patient presents with acute myocarditis and cardiogenic shock. The evolution is progressively favorable at the price of a residual involvement of the left ventricular function, evolving to a dilated cardiopathy, within three years. The responsibility of an advanced ictero-hemorrhagic leptospirosis is established. The severity of this myocarditis and the revealing characteristics of the leptospirosis are peculiar to this observation which is discussed in terms of data from the literature.