The authors report the case of a 15 year old boy with a large left ventricular fibroma discovered after a series of syncopal episodes due to obstruction to ejection. The first attempt to remove the fibroma in Columbia was only partially successful. In view of the risk of death associated with this type of tumour, it was decided to offer the patient complete excision after a full morphological and functional evaluation of myocardial function and the consequences of the tumour on mitral valve function and on the coronary circulation. The operation was performed under cardiopulmonary bypass and aortic clamping by conventional surgery, associated with reconstruction of the cardiac free wall with a large patch of autologous pericardium which was necessary to avoid cardiac transplantation, the ultimate sanction in this indication.