We report the first percutaneous mitral valvotomy performed in Portugal in October 19th 1987. The valvotomy was attempted successfully in a 34 year old man, with calcific mitral stenosis, in NYHA class III, with functional mitral valve area less then 1 cm2. The intervention was performed using the transseptal technique with two balloons (20 and 18 mm in diameter), placed in the mitral valve annulus through two long transseptal sheaths (14F). The procedure resulted in a marked decrease in the diastolic transmitral gradient, and an increase in mitral valve area superior to 100%. No immediate or late complications were observed, namely mitral regurgitation or left to right shunt through the atrial septum. One year later the patient is in NYHA class I, with a mitral valve area of 1.7 cm2.