The authors report the case of chronic dissection of the aorta presenting with congestive cardiac failure. The diagnosis was made for the first time by transoesophageal echocardiography which showed both the dissection of the aorta and its fistulalisation into the pulmonary artery. Aortography confirmed the diagnosis. The patient underwent surgery which consisted of suture of the fistula and replacement of the ascending aorta with a prosthetic tube. The outcome was favourable after 8 months follow-up.